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Sample records for wastewater alga chlorella

  1. Wastewater treatment with algae

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    Wong Yukshan [Hong Kong Univ. of Science and Technology, Kowloon (China). Research Centre; Tam, N.F.Y. [eds.] [City Univ. of Hong Kong, Kowloon (China). Dept. of Biology and Chemistry

    1998-05-01

    Immobilized algal technology for wastewater treatment purposes. Removal of copper by free and immobilized microalga, Chlorella vulgaris. Biosorption of heavy metals by microalgae in batch and continuous systems. Microalgal removal of organic and inorganic metal species from aqueous solution. Bioaccumulation and biotransformation of arsenic, antimony and bismuth compounds by freshwater algae. Metal ion binding by biomass derived from nonliving algae, lichens, water hyacinth root and spagnum moss. Metal resistance and accumulation in cyanobacteria. (orig.)

  2. Removal of Inorganic Nutrient and Organic Carbon from Wastewater of Binh Dien Market Using Green Alga Chlorella sp

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    Ha Bui Manh

    2016-12-01

    Full Text Available Traditional markets play a major role in socio-economics and constitutes a significant aspect of Vietnamese culture. However, wastewater streams discharged from the markets are generally characterized by a lot of inorganic nutrients and organic substances originated from fresh food processing units. They could lead to serious water contamination if discharged without proper treatment. This study applied microalgae Chlorella sp. for eliminating inorganic nutrients (NO3−-N, NH4+-N and PO43−-P and organic carbon (Chemical oxygen demand-COD from wastewater of the Binh Dien market. The removal efficiencies reached for NH4+-N > 86%, for NO3−-N > 72%, and for PO43−-P > 69%, respectively, at algal density of 49 × 104 cell mL−1, and for COD > 96% at algal density of 35 × 104 cell mL−1 after five cultivating days. The effluence satisfied the Vietnamese standard, column B, of the National technical regulation on industrial wastewater (QCVN 40:2011/BTNMT. The results demonstrated that the culture system composed of green algal Chlorella sp. could be a potential candidate for the removal of nutrients and organic carbon by a wastewater treatment process from the Binh Dien market.

  3. Biomass Production Potential of a Wastewater Alga Chlorella vulgaris ARC 1 under Elevated Levels of CO2 and Temperature

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    Senthil Chinnasamy

    2009-02-01

    Full Text Available The growth response of Chlorella vulgaris was studied under varying concentrations of carbon dioxide (ranging from 0.036 to 20% and temperature (30, 40 and 50oC. The highest chlorophyll concentration (11 µg mL-1 and biomass (210 µg mL-1, which were 60 and 20 times more than that of C. vulgaris at ambient CO2 (0.036%, were recorded at 6% CO2 level. At 16% CO2 level, the concentrations of chlorophyll and biomass values were comparable to those at ambient CO2 but further increases in the CO2 level decreased both of them. Results showed that the optimum temperature for biomass production was 30oC under elevated CO2 (6%. Although increases in temperature above 30oC resulted in concomitant decrease in growth response, their adverse effects were significantly subdued at elevated CO2. There were also differential responses of the alga, assessed in terms of NaH14CO3 uptake and carbonic anhydrase activity, to increases in temperature at elevated CO2. The results indicated that Chlorella vulgaris grew better at elevated CO2 level at 30oC, albeit with lesser efficiencies at higher temperatures.

  4. Growing Chlorella sp. on meat processing wastewater for nutrient removal and biomass production.

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    Lu, Qian; Zhou, Wenguang; Min, Min; Ma, Xiaochen; Chandra, Ceria; Doan, Yen T T; Ma, Yiwei; Zheng, Hongli; Cheng, Sibo; Griffith, Richard; Chen, Paul; Chen, Chi; Urriola, Pedro E; Shurson, Gerald C; Gislerød, Hans R; Ruan, Roger

    2015-12-01

    In this work, Chlorella sp. (UM6151) was selected to treat meat processing wastewater for nutrient removal and biomass production. To balance the nutrient profile and improve biomass yield at low cost, an innovative algae cultivation model based on wastewater mixing was developed. The result showed that biomass yield (0.675-1.538 g/L) of algae grown on mixed wastewater was much higher than that on individual wastewater and artificial medium. Wastewater mixing eased the bottleneck for algae growth and contributed to the improved biomass yield. Furthermore, in mixed wastewater with sufficient nitrogen, ammonia nitrogen removal efficiencies (68.75-90.38%) and total nitrogen removal efficiencies (30.06-50.94%) were improved. Wastewater mixing also promoted the synthesis of protein in algal cells. Protein content of algae growing on mixed wastewater reached 60.87-68.65%, which is much higher than that of traditional protein source. Algae cultivation model based on wastewater mixing is an efficient and economical way to improve biomass yield. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Ecotoxicity tests using the green algae Chlorella vulgaris-A useful tool in hazardous effluents management

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    Silva, Aurora [REQUIMTE, Instituto Superior de Engenharia do Instituto Politecnico do Porto, R. Antonio Bernardino de Almeida, 431 4200-072 Porto (Portugal); Figueiredo, Sonia A., E-mail: saf@isep.ipp.pt [REQUIMTE, Instituto Superior de Engenharia do Instituto Politecnico do Porto, R. Antonio Bernardino de Almeida, 431 4200-072 Porto (Portugal); Sales, M. Goreti; Delerue-Matos, Cristina [REQUIMTE, Instituto Superior de Engenharia do Instituto Politecnico do Porto, R. Antonio Bernardino de Almeida, 431 4200-072 Porto (Portugal)

    2009-08-15

    The treatment efficiency of laboratory wastewaters was evaluated and ecotoxicity tests with Chlorella vulgaris were performed on them to assess the safety of their environmental discharge. For chemical oxygen demand wastewaters, chromium (VI), mercury (II) and silver were efficiently removed by chemical treatments. A reduction of ecotoxicity was achieved; nevertheless, an EC50 (effective concentration that causes a 50% inhibition in the algae growth) of 1.5% (v/v) indicated still high level of ecotoxicity. For chloride determination wastewaters, an efficient reduction of chromium and silver was achieved after treatment. Regarding the reduction of ecotoxicity observed, EC50 increased from 0.059% to 0.5%, only a 0.02% concentration in the aquatic environment would guarantee no effects. Wastewaters containing phenanthroline/iron (II) complex were treated by chemical oxidation. Treatment was satisfactory concerning chemical parameters, although an increase in ecotoxicity was observed (EC50 reduced from 0.31% to 0.21%). The wastes from the kinetic study of persulphate and iodide reaction were treated with sodium bisulphite until colour was removed. Although they did not reveal significant ecotoxicity, only over 1% of the untreated waste produced observable effects over algae. Therefore, ecotoxicity tests could be considered a useful tool not only in laboratory effluents treatment, as shown, but also in hazardous wastewaters management.

  6. Removal of Nitrate and Phosphate from Municipal Wastewater Sludge by Chlorella vulgaris, Spirulina platensis and Scenedesmus quadricauda

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    Jalal K.C.A; Md Zahangir Alam; Matin W. A.; Kamaruzzaman B. Y.; Akbar J.; and Tofazzel Hossain

    2011-01-01

    Nitrate and phosphorus in wastewater contribute to health and environmental threats as they are linked to illnesses as well as ecosystem disruption via algal blooms in contaminated water bodies. Based on above perspectives a comparative study was conducted on three local freshwater microalgae:Chlorella vulgaris, Spirulina platensis and Scenedesmus quadricauda to evaluate their effects on nitrate and phosphorus removal from municipal wastewater sludge (MWS). Algae performance in removing nitra...

  7. Culture of green algae Chlorella ellipsoidea in inexpensive media

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    Rahman,M. S.; Hossain, M Anwar; Fatema, S.; Hossain, M. Amzad

    2005-01-01

    The culture of the of green alga Chlorella ellipsoidea was conducted under natural conditions at the same place simultaneously in five different media, viz., medium-I (inorganic medium), medium-II (powdered whole-pulse medium), medium-III (medium of pulse bran), medium-IV (mixed medium = 50% inorganic medium + 50% whole-pulse powder medium), medium-V (mixed medium = 50% inorganic medium + 50% pulse bran medium). The culture was done in 500 ml conical flask. Growth rates of C. ellipsoidea in f...

  8. Removal of Nitrate and Phosphate from Municipal Wastewater Sludge by Chlorella vulgaris, Spirulina platensis and Scenedesmus quadricauda

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    Jalal K.C.A

    2011-12-01

    Full Text Available Nitrate and phosphorus in wastewater contribute to health and environmental threats as they are linked to illnesses as well as ecosystem disruption via algal blooms in contaminated water bodies. Based on above perspectives a comparative study was conducted on three local freshwater microalgae:Chlorella vulgaris, Spirulina platensis and Scenedesmus quadricauda to evaluate their effects on nitrate and phosphorus removal from municipal wastewater sludge (MWS. Algae performance in removing nitrate and phosphorus was evaluated by measuring nitrate and phosphorus content of MWS incubated with the strains for 7 days. Instantaneous readings were taken every 48 hours to determine periodic levels of the nutrients phosphate and nitrate. BOD5 was also evaluated to identify the strain with the most robust growth that would demand for oxygen the most in the dark. Spirulina platensis was shown as the most efficient microalgae to reduce nitrate in MWS and the best-growing among the three strains, while Chlorella vulgaris removed phosphorus the most effectively. Thus Spirulina and Chlorella could be potential candidates by showing their intrinsic merit for the reduction of phosphate and nitrate in wastewater treatment.ABSTRAK: Nitrat dan fosforus dalam air sisa menggugat kesihatan dan mengancam alam sekitar memandangkan ia berkait dengan penyakit-penyakit serta gangguan terhadap ekosistem melalui pembiakan alga dalam air yang tercemar. Berdasarkan perspektif di atas, satu kajian perbandingan telah dijalankan terhadap tiga mikro alga air tawar tempatan : Chlorella vulgaris, Spirulina platensis dan Scenedesmus quadricauda untuk dinilai kesannya terhadap penyingkiran nitrat dan fosforus dari enap cemar air sisa bandaran (municipal wastewater sludge (MWS. Kebolehan alga dalam penyingkiran nitrat dan fosforus dikaji dengan menyukat kandungan nitrat dan fosforus dalam MWS yang dieramkan dengan strain ini selama 7 hari. Bacaan serta-merta diambil setiap 48 jam untuk

  9. Ammonium reduces chromium toxicity in the freshwater alga Chlorella vulgaris.

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    Liu, Jingqing; Sun, Zhengqi; Lavoie, Michel; Fan, Xiaoji; Bai, Xiaocui; Qian, Haifeng

    2015-04-01

    The aim of the present study was to investigate the protective effect of ammonium (NH4 (+)) on Cr toxicity to the freshwater alga Chlorella vulgaris. We followed an array of cellular functions and biomolecules in C. vulgaris cells exposed to 50 or 100 μM Cr at three different initial NH4 (+) concentrations (0.5, 3, and 10 mM). The results showed that Cr strongly inhibited cell yield of C. vulgaris, but 10 mM NH4 (+) could decrease by more than two-fold Cr toxicity on cell yield compared to exposure to 0.5 mM NH4 (+). Cr toxicity on gene transcripts and cellular substructure was also much lower at high than at low NH4 (+). Our results suggest that this protecting effect of NH4 (+) on intracellular Cr toxicity could be due to several factors, such as enhance uptake of phosphorus, increase in C and N assimilation efficiency, and increase transcription of photosynthesis-related genes.

  10. Impact of excipients in the chronic toxicity of fluoxetine on the alga Chlorella vulgaris.

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    Silva, Aurora; Santos, Lúcia H M L M; Delerue-Matos, Cristina; Figueiredo, Sónia A

    2014-01-01

    Fluoxetine is a selective serotonin reuptake inhibitor (SSRI) widely used in the treatment of major depression. It has been detected in surface and wastewaters, being able to negatively affect aquatic organisms. Most of the ecotoxicity studies focused only in pharmaceuticals, though excipients can also pose a risk to non-target organisms. In this work the ecotoxicity of five medicines (three generic formulations and two brand labels) containing the same active substance (fluoxetine hydrochloride) was tested on the alga Chlorella vulgaris, in order to evaluate if excipients can influence their ecotoxicity. Effective concentrations that cause 50% of inhibition (EC50) ranging from 0.25 to 15 mg L⁻¹ were obtained in the growth inhibition test performed for the different medicines. The corresponding values for fluoxetine concentration are 10 times lower. Higher EC50 values had been published for the same alga considering only the toxicity of fluoxetine. Therefore, this increase in toxicity may be attributed to the presence of excipients. Thus more studies on ecotoxicological effects of excipients are required in order to assess the environmental risk they may pose to aquatic organisms.

  11. Immunolmodulatory activity of the alga Chlorella vulgaris in Ehrlich ascites tumor bearing mice

    OpenAIRE

    2008-01-01

    Resumo: A Chlorella vulgaris (CV) é uma alga microscópica bastante rica em nutrientes. Além de alto valor nutritivo, a Chlorella tem demonstrado possuir importantes atividades terapêuticas. Vários trabalhos do nosso laboratório e outros demonstram os efeitos protetores desta alga contra infecções virais e bacterianas, tumores, entre outros. No presente trabalho avaliamos os efeitos do tratamento profilático/terapêutico com a dose de 50mg/Kg/dia de CV sobre a resposta imunohematopoética de ani...

  12. Experimental and kinetic studies for phycoremediation and dye removal by Chlorella pyrenoidosa from textile wastewater.

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    Pathak, Vinayak V; Kothari, Richa; Chopra, A K; Singh, D P

    2015-11-01

    Potential of Chlorella pyrenoidosa was experimentally investigated for phycoremediation and dye removal from textile wastewater (TWW) in batch cultures. Growth of alga was observed at various concentration of textile wastewater (25%, 50%, 75% and 100%) and was found in a range of 8.1-14 μg ml(-1) day(-1). Growth study revealed that alga potentially grows up to 75% concentrated textile wastewater and reduces phosphate, nitrate and BOD by 87%, 82% and 63% respectively. Methylene blue dye (MB) removal was also observed by using dry and wet algal biomass harvested after phycoremediation. Adsorption isotherms (Langmuir and Freundlich) and kinetic models (pseudo first and second order) were applied on adsorption process. Dry algal biomass (DAB) was found more efficient biosorbent with large surface area and showed high binding affinity for MB dye in compare to wet algal biomass (WAB). The RL value for both biosorbent showed feasible adsorption process as the obtained value was between 0 and 1. Pseudo second order kinetic model with high degree of correlation coefficient and low sum of error squares (SSE %) value was found more suitable for representation of adsorption process in case of both biosorbents, however pseudo first order also showed high degree of correlation for both biosorbents.

  13. Mitigating ammonia nitrogen deficiency in dairy wastewaters for algae cultivation.

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    Lu, Qian; Zhou, Wenguang; Min, Min; Ma, Xiaochen; Ma, Yiwei; Chen, Paul; Zheng, Hongli; Doan, Yen T T; Liu, Hui; Chen, Chi; Urriola, Pedro E; Shurson, Gerald C; Ruan, Roger

    2016-02-01

    This study demonstrated that the limiting factor to algae growth on dairy wastewater was the ammonia nitrogen deficiency. Dairy wastewaters were mixed with a slaughterhouse wastewater that has much higher ammonia nitrogen content. The results showed the mixing wastewaters improved the nutrient profiles and biomass yield at low cost. Algae grown on mixed wastewaters contained high protein (55.98-66.91%) and oil content (19.10-20.81%) and can be exploited to produce animal feed and biofuel. Furthermore, algae grown on mixed wastewater significantly reduced nutrient contents remained in the wastewater after treatment. By mitigating limiting factor to algae growth on dairy wastewaters, the key issue of low biomass yield of algae grown on dairy wastewaters was resolved and the wastewater nutrient removal efficiency was significantly improved by this study. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Influence of green algae Chlorella vulgaris on initial growth of different agricultural crops

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    Hajnal-Jafari Timea I.

    2016-01-01

    Full Text Available The aim of this research was to evaluate the effect of green algae Chlorella vulgaris on the initial growth of wheat, maize, bean and lettuce and the microbiological activity of rhizospheric soil. The experiment was conducted in controlled conditions. The inocula were applied as foliar fertilizer by spraying. Plant material was taken 30 days after plant emergance. Chlorella vulgaris affected positively the length (28.5% increase and fresh mass (17.9% increase of maize root, stem length of wheat (24.2% increase and stem mass of lettuce (56.34% increase. Application of Chlorella vulgaris led to the increase of the total number of bacteria and the number of aminoheterotrophs in the maize rhizosphere, total bacterial number in the wheat rhizosphere, and the number of fungi in the rhizosphere of bean. The number of other investigated groups of microorganisms did not change significantly. The activity of dehydrogenase enzyme was not affected by inoculation with green algae.

  15. Electricity and biomass production in a bacteria-Chlorella based microbial fuel cell treating wastewater

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    Commault, Audrey S.; Laczka, Olivier; Siboni, Nachshon; Tamburic, Bojan; Crosswell, Joseph R.; Seymour, Justin R.; Ralph, Peter J.

    2017-07-01

    The chlorophyte microalga Chlorella vulgaris has been exploited within bioindustrial settings to treat wastewater and produce oxygen at the cathode of microbial fuel cells (MFCs), thereby accumulating algal biomass and producing electricity. We aimed to couple these capacities by growing C. vulgaris at the cathode of MFCs in wastewater previously treated by anodic bacteria. The bioelectrochemical performance of the MFCs was investigated with different catholytes including phosphate buffer and anode effluent, either in the presence or absence of C. vulgaris. The power output fluctuated diurnally in the presence of the alga. The maximum power when C. vulgaris was present reached 34.2 ± 10.0 mW m-2, double that observed without the alga (15.6 ± 9.7 mW m-2), with a relaxation of 0.19 gL-1 d-1 chemical oxygen demand and 5 mg L-1 d-1 ammonium also removed. The microbial community associated with the algal biofilm included nitrogen-fixing (Rhizobiaceae), denitrifying (Pseudomonas stutzeri and Thauera sp., from Pseudomonadales and Rhodocyclales orders, respectively), and nitrate-reducing bacteria (Rheinheimera sp. from the Alteromonadales), all of which likely contributed to nitrogen cycling processes at the cathode. This paper highlights the importance of coupling microbial community screening to electrochemical and chemical analyses to better understand the processes involved in photo-cathode MFCs.

  16. Metal distributions in complexes with Chlorella vulgaris in seawater and wastewater

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    Pascucci, P.R.; Kowalak, A.D.

    1999-10-01

    Divalent cadmium (Cd), copper (Cu), iron (Fe), nickel (Ni), lead (Pb), and zinc (Zn) simultaneous complexes with an algal biomass Chlorella vulgaris were studied for bioremediation purposes in various aqueous media: distilled-deionized water (DDIW), seawater, nuclear-reactor pool water, and process wastewater. Reactions were monitored using various dry masses of algae at constant temperature and constant metal concentrations for reaction times ranging from 0 to 150 minutes. Complexes occurred within 30 minutes and reached a steady state after 80 to 120 minutes. Distribution constants (K{prime}{sub d}) were calculated for the complexes and relative orders of K{prime}{sub d} were reported. The K{prime}{sub d} are used to evaluate relative efficiency of metal remediation from waters. Lead, Cu, and Ni complexes had the greatest K{prime}{sub d} values and those metals were most efficiently removed from these waters. Zinc and Fe formed the most labile complexes. The order of K{prime}{sub d} values for complexes in DDIW was Pb > Cu > Cd > Zn, then Cu > Cd > Zn in seawater, Cd > Cu > Zn in reactor pool water, and Ni > Cd > Cu > Zn > Fe in wastewater. C. vulgaris biomass may potentially be used as an alternative to traditional water treatment methods for simultaneous extraction of metals from seawater, process wastewater, or drinking water.

  17. Cultivation of microalgal Chlorella for biomass and lipid production using wastewater as nutrient resource.

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    Chiu, Sheng-Yi; Kao, Chien-Ya; Chen, Tsai-Yu; Chang, Yu-Bin; Kuo, Chiu-Mei; Lin, Chih-Sheng

    2015-05-01

    Using wastewater for microalgal cultures is beneficial for minimizing the use of freshwater, reducing the cost of nutrient addition, removing nitrogen and phosphorus from wastewater and producing microalgal biomass as bioresources for biofuel or high-value by-products. There are three main sources of wastewater, municipal (domestic), agricultural and industrial wastewater, which contain a variety of ingredients. Some components in the wastewater, such as nitrogen and phosphorus, are useful ingredients for microalgal cultures. In this review, the effects on the biomass and lipid production of microalgal Chlorella cultures using different kinds of wastewater were summarized. The use of the nutrients resource in wastewater for microalgal cultures was also reviewed. The effect of ammonium in wastewater on microalgal Chlorella growth was intensively discussed. In the end, limitations of wastewater-based of microalgal culture were commented in this review article.

  18. Toxicological Response of the Green Alga Chlorella vulgaris, to Some Heavy Metals

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    E. Afkar

    2010-01-01

    Full Text Available Problems statement: The disturbance of aquatic ecosystems provoked by heavy metals pollution from industrial and domestic sources, has as consequence the loss of biological diversity, as well as increased bioaccumulation and magnification of toxicants in the food chain. The aim of this study was to evaluate the effect of some heavy metals on some physiological activities of Chlorella vulgaris beyerinck with special references to metal bioaccumulation. Approach: Chlorella vulgaris Beyerinck was isolated from Al-Asfar Lake, Al-Hassa, Saudi Arabia. A standard initial inoculum of the isolated algae was inoculated to culture flasks. The culture flasks were supplied with various concentrations of Cobalt, Copper and Zinc ranging from 10-6-10-9 M. At the end of the incubation period cultures were filtered and washed several times by distilled water for measurements the various experimental parameters. Results: The data show that the lower doses of the three tested metals had stimulatory effect in biomass yield of Chlorella vulgaris, whereas the higher doses were inhibitory depending on the type of the metal. The inhibitory effect of copper to the growth parameters of Chlorella vulgaris was more pronounced than other two tested metals. The total protein content, total carbohydrate and the total free amino acids of the tested green alga Chlorella vulgaris gradually decreased in a manner dependent on the metal concentration in the medium. On the other hand, bioaccumulation of cobalt, copper and zinc by Chlorella vulgaris cells were parallel to increasing the concentrations in the culture medium. Conclusion: The inhibitory and stimulatory effects of either of the used heavy metals depend on concentration. Different organisms, however, have different sensitivities to the same metal and the same organisms may be more or less damaged by different metals. The uptake of an element from the surrounding medium is seldom exactly proportional to the amount present

  19. Inhibitory effects of silver nanoparticles in two green algae, Chlorella vulgaris and Dunaliella tertiolecta.

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    Oukarroum, Abdallah; Bras, Sébastien; Perreault, François; Popovic, Radovan

    2012-04-01

    Freshwater microalga Chlorella vulgaris and marine microalga Dunaliella tertiolecta were used to investigate toxic effects induced by 50 nm silver nanoparticles (AgNPs). To induce AgNPs effect, we exposed Chlorella vulgaris and Dunaliella tertiolecta for 24h to 0-10 mg/L. We showed that growth media had different effects in AgNPs agglomerates' formation. Cellular viability, reactive oxygen species (ROS) formation and lipids peroxidation were employed to assess the toxic effects of AgNPs. AgNPs were able to interact directly with the Chlorella vulgaris cells surface and large aggregates were observed. AgNPs have a negative effect on Chlorella vulgaris and Dunaliella tertiolecta, as manifested by a strong decrease in chlorophyll content, viable algal cells, increased ROS formation and lipids peroxidation. The variability in sensitivity of both algae towards AgNPs was observed. We conclude that AgNPs have a negative effect on aquatic algae and these alterations might have serious consequences on structure and function of aquatic plant communities.

  20. Bioavailability of wastewater derived dissolved organic nitrogen to green microalgae Selenastrum capricornutum, Chlamydomonas reinhardtii, and Chlorella vulgaris with/without presence of bacteria.

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    Sun, Jingyi; Simsek, Halis

    2017-07-01

    Effluent dissolved organic nitrogen (DON) is problematic in nutrient sensitive surface waters and needs to be reduced to meet demanding total dissolved nitrogen discharge limits. Bioavailable DON (ABDON) is a portion of DON utilized by algae or algae+bacteria, while biodegradable DON (BDON) is a portion of DON decomposable by bacteria. ABDON and BDON in a two-stage trickling filter (TF) wastewater treatment plant was evaluated using three different microalgal species, Selenastrum capricornutum, Chlamydomonas reinhardtii and Chlorella vulgaris and mixed cultured bacteria. Results showed that up to 80% of DON was bioavailable to algae or algae+bacteria inoculum while up to 60% of DON was biodegradable in all the samples. Results showed that C. reinhardtii and C. vulgaris can be used as a test species the same as S. capricornutum since there were no significant differences among these three algae species based on their ability to remove nitrogen species. Copyright © 2017. Published by Elsevier B.V.

  1. Genetic diversity analysis with ISSR PCR on green algae Chlorella vulgaris and Chlorella pyrenoidosa

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    Shen, Songdong

    2008-11-01

    In the present study, genetic polymorphism and diversity in unicellular clones of Chlorella vulgaris Beijerinck and Chlorella pyrenoidosa Chick were studied with Inter Simple Sequence Repeats PCR (ISSR PCR). Samples including four clones of C. vulgaris and three clones of C. pyrenoidosa were purified by single-clone-choice method. For four C. vulgaris unicellular clones, the total number of the bands scored for 18 primers was 298; and the number of the polymorphic bands was 118, of which 39.6% were polymorphic. The size of PCR products ranged from 200 to 2 500 bp. The total number of bands scored for 18 primers, the number of polymorphic bands and the percentage of three C. pyrenoidosa unicellular clones was 194.83 and 30.8%, respectively. POPGENE analysis show that the average Nei genetic diversity (h*) and Shannon index of diversity (I*) in the four C. vulgaris unicellular clones was 0.2181 and 0.3208, respectively, which is slightly higher than those of the three C. pyrenoidosa unicellular clones (0.190 3 and 0.274 8), which agreed with the percentage of polymorphic bands in the mixed samples of the two species. The results suggest that ISSR is a useful method to Chlorella for intraspecies genetic analysis.

  2. Genetic diversity analysis with ISSR PCR on green algae Chlorella vulgaris and Chlorella pyrenoidosa

    Institute of Scientific and Technical Information of China (English)

    SHEN Songdong

    2008-01-01

    In the present study, genetic polymorphism and diversity in unicellular clones of Chlorella vulgaris Beijerinck and Chlorella pyrenoidosa Chick were studied with Inter Simple Sequence Repeats PCR (ISSR PCR). Samples including four clones of C. vulgaris and three clones of C. pyrenoidosa were purified by single-clone-choice method. For four C. vulgaris unicellular clones, the total number of the bands scored for 18 primers was 298; and the number of the polymorphic bands was 118, of which 39.6% were polymorphic. The size of PCR products ranged from 200 to 2 500 bp. The total number of bands scored for 18 primers, the number of polymorphic bands and the percentage of three C. pyrenoidosa unicellular clones was 194.83 and 30.8%, respectively. POPGENE analysis show that the average Nei genetic diversity (h *) and Shannon index of diversity (I *) in the four C. vulgaris unicellular clones was 0.2181 and 0.3208, respectively, which is slightly higher than those of the three C. pyrenoidosa unicellular clones (0.190 3 and 0.274 8), which agreed with the percentage of polymorphic bands in the mixed samples of the two species. The results suggest that ISSR is a useful method to Chlorella for intra-species genetic analysis.

  3. Impact of green algae on the measurement of Microcystis aeruginosa populations in lagoon-treated wastewater with an algae online analyser.

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    Nguyen, Thang; Roddick, Felicity A; Fan, Linhua

    2015-01-01

    Tests on the algae online analyser (AOA) showed that there was a strong direct linear correlation between cell density and in vivo Chl-a concentration for M. aeruginosa over the range of interest for a biologically treated effluent at a wastewater treatment plant (25,000-65,000 cells mL(-1), equivalent to a biovolume of 2-6 mm3 L(-1)). However, the AOA can provide an overestimate or underestimate of M. aeruginosa populations when green algae are present in the effluent, depending on their species and relative numbers. The results from this study demonstrated that the green algae (e.g., Euglena gracilis, Chlorella sp.) in the field phytoplankton population should be considered during calibration. In summary, the AOA has potential for use as an alert system for the presence of M. aeruginosa, and thus potentially of cyanobacterial blooms, in wastewater stabilization ponds.

  4. PHYCOREMEDIATION AND THE POTENTIAL OF SUSTAINABLE ALGAL BIOFUEL PRODUCTION USING WASTEWATER

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    Adel A. Fathi

    2013-01-01

    Full Text Available Wastewater remediation by microalgae is an eco-friendly process with no secondary pollution as long as the biomass produced is reused and allows efficient nutrient recycling. This study was undertaken to evaluate the remediation of wastewater by the green alga Chlorella vulgaris and the potential of these alga (biomass to produce sustainable biofuel. The results shows that the cultivation of green alga Chlorella vulgaris on wastewater has a positive effect on removal the major inorganic elements form the wastewater. Biodiesel can be produced from Chlorella vulgaris. The Chlorella vulgaris can be used for remediation of wastewater and the producing biomass can be used as source of renewable energy.

  5. Fungal pretreatment of raw digested piggery wastewater enhancing the survival of algae as biofuel feedstock.

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    Liu, Junying; Qiu, Wen; Wang, Yunpu

    2017-01-01

    Understanding about the impact of white rot fungi on indigenous bacterial communities, NH4(+) and turbidity in digested piggery wastewater, will allow the optimization of wastewater treatment methods and its use as a feasible medium for algal growth. Here, the white rot fungi were inoculated into undiluted and unsterilized digested piggery wastewater under different temperatures and pH regimes in order to lower the pretreatment cost. Diversity and abundance of the bacterial communities in the pretreated wastewater were assessed by PCR-denaturing gradient gel electrophoresis coupled with 16S rDNA sequencing. The research showed a significant reduction on the microbial diversity with the presence of white rot fungi which occur at pH 6. The distribution and presence of bacteria taxa were strongly correlated with NH4(+) concentration, pH, and the presence of white rot fungi. Variance partition analysis also showed that the effect on the chlorophyll content of algae in fungi-filtered wastewater was as the following hierarchy: bacterial diversity > NH4(+) > turbidity. Therefore, the algae in treated wastewater with less abundance of bacteria proliferated more successfully, indicating that bacterial community not only played an important role in algal growth but also imposed a strong top-down control on the algal population. The algae grown in wastewater treated with fungi reached the highest specific growth rate (0.033 day(-1)), whereas the controls displayed the negative specific growth rate. The fatty acid composition varied markedly in C16:0 and C18:0 between these treatments, with a higher content of C16:0. This study firstly showed that Chlorella can grow as cost-effective biofuel feedstocks in undiluted and unsterilized digested wastewater with high ammonium concentration and dark brown color because the bacterial abundance of digested piggery wastewater could be reduced greatly by the white rot fungi.

  6. Kinetics of nutrient removal and expression of extracellular polymeric substances of the microalgae, Chlorella sp. and Micractinium sp., in wastewater treatment.

    Science.gov (United States)

    Wang, Meng; Kuo-Dahab, Wenye Camilla; Dolan, Sona; Park, Chul

    2014-02-01

    Two species of green algae, Chlorella sp. and Micractinium sp., were cultivated in primary effluent wastewater and high-strength wastewater (a mixture of anaerobic digestion centrate and primary effluent) to study nutrient removal and EPS (extracellular polymeric substances) expression during their growth. The high N concentration and P-limited condition in the mixed wastewater (total N=197 mg/L; N/P mass ratio=56) led to about 3 times greater specific N removal rate than the primary effluent set, indicating that algal cells growing in N-rich wastewater had N over-uptake. Both Chlorella and Micractinium grown in the high-strength wastewater also produced larger amounts of protein EPS, possibly accounting for higher N uptake in those cultivation sets. These results suggest that different types of wastewater could cause different nutrient removal kinetics and EPS expression by algae, which may subsequently influence harvesting and anaerobic digestion of their biomass. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Evaluation of sample extraction methods for proteomics analysis of green algae Chlorella vulgaris.

    Science.gov (United States)

    Gao, Yan; Lim, Teck Kwang; Lin, Qingsong; Li, Sam Fong Yau

    2016-05-01

    Many protein extraction methods have been developed for plant proteome analysis but information is limited on the optimal protein extraction method from algae species. This study evaluated four protein extraction methods, i.e. direct lysis buffer method, TCA-acetone method, phenol method, and phenol/TCA-acetone method, using green algae Chlorella vulgaris for proteome analysis. The data presented showed that phenol/TCA-acetone method was superior to the other three tested methods with regards to shotgun proteomics. Proteins identified using shotgun proteomics were validated using sequential window acquisition of all theoretical fragment-ion spectra (SWATH) technique. Additionally, SWATH provides protein quantitation information from different methods and protein abundance using different protein extraction methods was evaluated. These results highlight the importance of green algae protein extraction method for subsequent MS analysis and identification.

  8. Cultivation of Chlorella vulgaris on wastewater containing high levels of ammonia for biodiesel production.

    Science.gov (United States)

    He, P J; Mao, B; Shen, C M; Shao, L M; Lee, D J; Chang, J S

    2013-02-01

    The feasibility of cultivating Chlorella vulgaris with wastewater containing high ammonia nitrogen concentrations was examined. The average specific growth rate of C. vulgaris was 0.92 d(-1) at 17 mg L(-1) NH4+-N, but declined to 0.33 d(-1) at NH4+-N concentrations of 39-143 mg L(-1). At 39 mg L(-1) NH4+-N, lipid productivity reached a maximum value (23.3 mg L(-1)d(-1)) and dropped sharply at higher NH4+-N levels, which demonstrated NH4+-N should be controlled for biodiesel production. C16 and C18 fatty acids accounted for 80% of total fatty acids. Increasing NH4+-N from 17 to 207 mg L(-1) yielded additional short-chain and saturated fatty acids. Protein content was in positive correlation with NH4+-N content from 17 mg L(-1) (12%) to 207 mg L(-1) (42%). Carbohydrate in the dried algae cell was in the range of 14-45%, with a peak value occurring at 143 mg L(-1) NH4+-N. The results demonstrate that product quality can be manipulated by NH4+-N concentrations of the initial feeds. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Use of Chlorella for the Treatment of the Soft-shelled Turtle Processing Wastewater

    Directory of Open Access Journals (Sweden)

    Yong-jun Zhang

    2013-12-01

    Full Text Available The capability of Chlorella vulgaris to remove nitrogen in the form of ammonium ions from the soft-shelled turtle processing wastewater in a local agricultural products limited company (in Hangzhou, China was studied. The soft-shelled turtle processing wastewater was found to include high concentrations of nitrogen (107.63±4.84 mg/L in the form of ammonium (NH4+ with the small amounts of nitrite (0.32±0.04 mg/L on annual average at pH 6.7 and to be suitable for growing Chlorella vulgaris. When Chlorella vulgaris was cultivated in a batch mode, a majority of the nitrogen concentration was dramatically removed after a lag-phase period. The total biomass weight gained during the entire cultivation period balanced out well with the nitrogen removed from the culture medium. These results indicate that Chlorella vulgaris has potential to remove nitrogen (i.e., ammonium ion and nitrite at a reasonable uptake rate from wastewater while being cultivated using the soft-shelled turtle processing wastewater.

  10. Acetone, butanol, and ethanol production from wastewater algae.

    Science.gov (United States)

    Ellis, Joshua T; Hengge, Neal N; Sims, Ronald C; Miller, Charles D

    2012-05-01

    Acetone, butanol, and ethanol (ABE) fermentation by Clostridium saccharoperbutylacetonicum N1-4 using wastewater algae biomass as a carbon source was demonstrated. Algae from the Logan City Wastewater Lagoon system grow naturally at high rates providing an abundant source of renewable algal biomass. Batch fermentations were performed with 10% algae as feedstock. Fermentation of acid/base pretreated algae produced 2.74 g/L of total ABE, as compared with 7.27 g/L from pretreated algae supplemented with 1% glucose. Additionally, 9.74 g/L of total ABE was produced when xylanase and cellulase enzymes were supplemented to the pretreated algae media. The 1% glucose supplement increased total ABE production approximately 160%, while supplementing with enzymes resulted in a 250% increase in total ABE production when compared to production from pretreated algae with no supplementation of extraneous sugar and enzymes. Additionally, supplementation of enzymes produced the highest total ABE production yield of 0.311 g/g and volumetric productivity of 0.102 g/Lh. The use of non-pretreated algae produced 0.73 g/L of total ABE. The ability to engineer novel methods to produce these high value products from an abundant and renewable feedstock such as algae could have significant implications in stimulating domestic energy economies.

  11. Photo-induced transformations of mercury(II) species in the presence of algae, Chlorella vulgaris

    Energy Technology Data Exchange (ETDEWEB)

    Deng Lin, E-mail: dlwhu@163.com [Department of Municipal Engineering, Southeast University, Nanjing 210096 (China); Fu Dafang [Department of Municipal Engineering, Southeast University, Nanjing 210096 (China); Deng Nansheng [School of Resources and Environmental Science, Wuhan University, Wuhan 430072 (China)

    2009-05-30

    The effects of algae (i.e., Chlorella vulgaris), Fe(III), humic substances, and pH on the photoreduction of Hg(II) under the irradiation of metal halide lamps ({lambda} {>=} 365 nm, 250 W) were investigated in this paper. The photoreduction rate of Hg(II) was found to increase with the increasing concentration of algae, Fe(III), and humic substances. The cooperation action of Fe(III) and humic substances accelerated the photoreduction of Hg(II). When the initial concentration of Hg(II) was in the range of 0.0-200.0 {mu}g L{sup -1} with initial algae concentrations 7.0 x 10{sup 9} cells L{sup -1} at pH 7.0, the initial photoreduction rate of Hg(II) could be expressed by the equation: -dC{sub Hg(II)}/dt = 0.65 x [C{sub Hg(II)}]{sup 0.39} with a correlation coefficient of R = 0.9912. The study on the photochemical process in terms of total mercury mass balance revealed that more than 40.86% of Hg(II) from the algal suspension was reduced to volatile metallic mercury. This paper discussed the photoreduction mechanism of Hg(II) in the presence of algae. This research will provide information for predicting the photoreduction of Hg(II) in the real environment. It will be helpful for understanding the photochemical transformation of Hg(II) and the formation of DGM in natural water in the presence of algae complexes. It will also be helpful for providing new methods to deal with heavy metal pollution.

  12. Influence of Speciation of Thorium on Toxic Effects to Green Algae Chlorella pyrenoidosa.

    Science.gov (United States)

    Peng, Can; Ma, Yuhui; Ding, Yayun; He, Xiao; Zhang, Peng; Lan, Tu; Wang, Dongqi; Zhang, Zhaohui; Zhang, Zhiyong

    2017-04-10

    Thorium (Th) is a natural radioactive element present in the environment and has the potential to be used as a nuclear fuel. Relatively little is known about the influence and toxicity of Th in the environment. In the present study, the toxicity of Th to the green algae Chlorella pyrenoidosa (C. pyrenoidosa) was evaluated by algal growth inhibition, biochemical assays and morphologic observations. In the cultural medium (OECD TG 201), Th(NO₃)₄ was transformed to amorphous precipitation of Th(OH)₄ due to hydrolysis. Th was toxic to C. pyrenoidosa, with a 96 h half maximum effective concentration (EC50) of 10.4 μM. Scanning electron microscopy shows that Th-containing aggregates were attached onto the surface of the algal cells, and transmission electron microscopy indicates the internalization of nano-sized Th precipitates and ultrastructural alterations of the algal cells. The heteroagglomeration between Th(OH)₄ precipitation and alga cells and enhanced oxidative stress might play important roles in the toxicity of Th. To our knowledge, this is the first report of the toxicity of Th to algae with its chemical species in the exposure medium. This finding provides useful information on understanding the fate and toxicity of Th in the aquatic environment.

  13. Preliminary study of the green algae chlorella (Chlorella vulgaris) for control on the root-knot nematode (Meloidogyne arenaria) in tomato plants and ectoparasite Xiphinema indexin grape seedlings.

    Science.gov (United States)

    Choleva, B; Bileva, T; Tzvetkov, Y; Barakov, P

    2005-01-01

    The alternative ecological methods require investigation of many organo-biological means for plant protection against dangerous root parasites such as root-knot nematode Meloidogyne arenaria and some ectoparasites (Xiphinema index). The Bulgarian organic product - dry extract of green alga Chlorella vulgaris ("The Golden Apple"-Plamen Barakov) is the latest product, which in comparative aspect gives the best results. Series of laboratory and pot experiments are carried out with tomato (cv. Bele and cv. Ideal) and grape seedlings (cv. Cabernet Sauvignon). Different dosages of Chlorella from 0.5 g to 2 g per plant/pot are investigated. The first results show that even low dosages had double effect - on the one hand they suppress the parasite development and on the other hand they strongly stimulate plant growing. The very important conclusion is that Chlorella vulgaris ignores the negative influence of M. arenaria and X. index. These results give us opportunity for future model and field investigations of Chlorella vulgaris with the aim of its practical application.

  14. Metabolitic activity of 11-deoxycorticosterone and prednisolone in the alga Chlorella vulgaris Beijerinck

    Directory of Open Access Journals (Sweden)

    Romuald Czerpak

    2014-01-01

    Full Text Available The influence of optimal concentrations 5 x 10-6M - 10-6M of 11-deoxycorticosterone (mineralocorticoid and prednisolone (glucocorticoid on the growth (fresh and dry weight and content of soluble proteins, reducing sugars and nucleic acids in the green alga Chlorella vulgaris (Chlorophyceae. Both corticosteroids at concentration 5 x 10-6M were most strongly active metabolically between the 5th-15th day of the cultivation and this probably was caused by their chemical biotransformation. The applied corticosteroids induced the strongest stimulative effect on the content of soluble proteins in the range of 167-196% and reducing sugars (233-275% when compared to the control (100%. Prednisolone showed lower stimulative activity on the content of proteins. But 11-deoxycorticosterone showed weaker stimulation of on the content of sugar. Both of the corticosteroids showed a stimulating or inhibitory influence upon the content of nucleic acids in C. vulgaris cells without regard to the concentration.

  15. Removal of nutrients by algae from municipal wastewater contaminated with heavy metals

    OpenAIRE

    Aryal, Bigyan

    2015-01-01

    Selected species of algae (green algae and blue green algae) were cultivated in municipal wastewater using PBR (photo-bioreactor) bottles. Uptake of nutrients by these algae species was measured on different dates. From the results of the experiments, it was observed that a combination of certain blue green algae species (cyanobacteria) was able to remove most of the nutrients from the wastewater. The presence of heavy metal ions in the wastewater also affected the nutrient-absorbing capacit...

  16. Discoloration of wastewater from a paint industry by the microalgae Chlorella sp

    Directory of Open Access Journals (Sweden)

    Edgardo Angulo M

    2017-09-01

    Full Text Available Objective. Decoloring wastewater from a paint factory making use of Chlorella sp., microalgae as a biological way of treatment. Materials and methods. Samples of this microalgae previously cultivated with nourishing fertilizer under photoperiods of light and darkness were taken to test the microalgae Chlorella sp., initial concentration effect in the bioremoval process. For this purpose, it was cultivated in 0.10, 0.20 and 0.30 units of absorbance in bioreactors with 200 mL wastewater with and without nutrients. The biotest with the best rate of colour removal was chosen and the DBO5 and DQO were marked out. The immobilized Chlorella sp., in kappa carrageenan was also tested. Results. In the tests colour decrease percentage were 81.7, 69.7 and 58.3% without nutrients in the initial concentrations of 0.10, 0.20 and 0.30 units of absorbance respectively and 72.6, 69.0 and 86.8% for 0.10, 0.20 and 0.30 units of absorbance with nutrients respectively in the day of maximum growth. The immobilized microalgae score were 72.60% and 78.36% of color removal for 0.4 and 1.6 units of absorbance respectively. The higher colour removal test score was that with nutrients at 0.30 units of absorbance with several changes in DBO5 and DQO values. Conclusion. The biological wastewater treatment making use of Chlorella sp., microalgae can be considered as an effective choice in decolorating wastewater.

  17. Cost-effective Chlorella biomass production from dilute wastewater using a novel photosynthetic microbial fuel cell (PMFC).

    Science.gov (United States)

    Ma, Jinxing; Wang, Zhiwei; Zhang, Junyao; Waite, T David; Wu, Zhichao

    2017-01-01

    While microalgae have been suggested as a promising substitute to conventional fossil fuels, their cost effective cultivation and harvesting constitutes a major challenge. In the work described here, a novel photosynthetic microbial fuel cell (PMFC) in which a stainless steel mesh with biofilm formed on it serves as both the cathode and filtration material has been developed. Results of this study reveal that, in addition to inducing oxygen reduction reactions under illumination, the biocathode is effective in preventing the washout of algae during continuous operation, resulting in retained biomass concentrations reaching 3.5-6.5 g L(-1). The maximum output current density reached ∼200 mA m(-2) under irradiation, which is comparable with recent PMFC studies. Microbial diversity analyses targeting 16S and 18S rRNA genes indicated that the eukaryotic species belonging to the genus Chlorella was able to sustain its community dominance (>96%) over other competing species over the course of the studies. In the absence of catalysts such as Pt, a consortium of photosynthetic organisms including plant growth-promoting bacteria such as Azospirillum and Rhizobium were overrepresented in the biofilm, with these organisms most likely contributing to cathodic electron transfer. Energy flow analysis suggested that the PMFC system held the potential to achieve theoretical energy balance in simultaneous algae production and wastewater treatment.

  18. Prospects of using unicellular algae protein in biological life-support systems. [Chlorella, Chlamydomonas, Spirulina, Euglena

    Energy Technology Data Exchange (ETDEWEB)

    Antonyan, A.A.; Abakumova, I.A.; Meleshko, G.I.; Vlasova, T.F.

    The concentration, amino acid composition and biological value of proteins of unicellular algae belonging to various taxonomic groups (Chlorella, Chlamydomonas, Spirulina, Euglena) were investigated. With respect to their characteristics, these algae hold promise as components of biological life-support systems (BLSS). Indices characterizing the protein and biomass quality and biological value were calculated. Such indices as A/E (where A is an essential amino acid and E is the sum total of amino acids), anti-E/T (where anti-E is nitrogen of essential amino acids and T is its sum total), amino acid number, factor of digestibility in vitro were high enough and close to the respective parameters of the reference protein. Animal experiments showed high biological value of the algal biomass and the lack of its toxic or other adverse effects. It is suggested that the differences in the protein composition associated with various algal forms and cultivation conditions can be used to produce balanced diets by varying the portion of each form of the photoautotropic component of BLSS.

  19. Selection of microalgae for high CO2 fixation efficiency and lipid accumulation from ten Chlorella strains using municipal wastewater.

    Science.gov (United States)

    Hu, Xia; Zhou, Jiti; Liu, Guangfei; Gui, Bing

    2016-08-01

    As significant differences in cellular physiology, metabolic potential and genetics occur among strains with morphological similarity, the screening of appropriate microalgae species for effective CO2 fixation and biodiesel production is extremely critical. In this study, ten strains of Chlorella were cultivated in municipal wastewater influent (MWI) and their tolerance for MWI, CO2 fixation efficiency and lipid productivity were assessed. The results showed that the biomass concentrations of four strains (Chlorella vulgaris, Chlorella 64.01, Chlorella regularis var. minima and Chlorella sp.) were significantly higher than other strains. When the cultivation systems were aerated with 10% CO2, Chlorella sp. showed the highest CO2 fixation efficiency (35.51%), while the highest lipid accumulation (58.48%) was observed with C. vulgaris. Scanning electron microscopy images revealed that the cells of both Chlorella sp. and C. vulgaris kept their normal morphologies after 15day batch culture. These findings indicated that Chlorella sp. and C. vulgaris have fairly good tolerance for MWI, and moreover, Chlorella sp. was appropriate for CO2 fixation while C. vulgaris represented the highest potential for producing biodiesel.

  20. Nutrients removal and lipids production by Chlorella pyrenoidosa cultivation using anaerobic digested starch wastewater and alcohol wastewater.

    Science.gov (United States)

    Yang, Libin; Tan, Xiaobo; Li, Deyi; Chu, Huaqiang; Zhou, Xuefei; Zhang, Yalei; Yu, Hong

    2015-04-01

    The cultivation of microalgae Chlorella pyrenoidosa (C. pyrenoidosa) using anaerobic digested starch wastewater (ADSW) and alcohol wastewater (AW) was evaluated in this study. Different proportions of mixed wastewater (AW/ADSW=0.176:1, 0.053:1, 0.026:1, v/v) and pure ADSW, AW were used for C. pyrenoidosa cultivation. The different proportions between ADSW and AW significantly influenced biomass growth, lipids production and pollutants removal. The best performance was achieved using mixed wastewater (AW/ADSW=0.053:1, v/v), leading to a maximal total biomass of 3.01±0.15 g/L (dry weight), lipids productivity of 127.71±6.31 mg/L/d and pollutants removal of COD=75.78±3.76%, TN=91.64±4.58% and TP=90.74±4.62%.

  1. Cultivating Chlorella vulgaris as biodiesel feedstock by municipal wastewater%利用市政污水培养Chlorella vulgaris生产生物柴油

    Institute of Scientific and Technical Information of China (English)

    刘建强; 刘玉环; 阮榕生; 刘茜; 张锦胜; 彭红; 巫小丹

    2011-01-01

    The technical feasibility by Nanchang municipal wastewater of Nanchang City was used as culture media for large-scale cultivation of oil-rich microalgae as biodiesel feedstock and treating the wastewater simultaneausly.Collecting the municipal wastewater without any treatment from Qingshanhu sewage plant as the culture medium for Chlorella vulgaris growth.The experiment monitored the specific growth rate and biomass yield of C.vulgaris and associated ammonia nitrogen, phosphorous, COD, TSS,and VSS removal during 10 days.The experimental results showed that the level of nutrients influenced algae growth significantly.The growth rate of C.vulgaris reached a maximum of OD680 2.856 after 8 days culturing and the algae biomass accumulation rate reached a maximum of 0.01 g/L per day.The oil content of C.vulgaris was 180 mg/g in dry biomass weight and the oil average daily production was 0.001 g/L per day.The removel rate of NH4+ -N, TP and COD were 50.0%, 32.1% and 26.0%.The TSS and VSS removal rates were 0.01 mg/L per day and 0.006 1 mg/L per day, respectively.%为了考察利用南昌市政污水规模化培养富油微藻生产生物柴油,同时达到净化污水的目的,取南昌市青山湖污水处理厂未经任何处理的市政污水作为普通小球藻(Chlorella vulgaris)生长的培养液.监测了C.vulgaris在市政污水中连续培养10 d的特定生长率、生物质产量以及与之相关的市政污水中氨氮(NH+4-N)、总磷(TP)、化学需氧量(COD)、总悬浮固体(TSS)和挥发性悬浮固体(VSS)的清除情况.实验表明:营养物质的水平显著地影响了C.vulgaris的生长.C.vulgaris的生长率在培养8 d后达到最大,OD680为2.856,总的生物质产量日均最大积累速率为0.01 g/L,油脂含量为干质量的18%,油脂的平均日产量为0.001 g/L.培养10 d内NH+4-N、TP和COD的去除率分别为50.0%、32.1%和26.0%, TSS和VSS的日平均去除速率分别为0.01 g/L 和0.006 1 g/L.

  2. Evaluation of antiangiogenic and antiproliferative potential of the organic extract of green algae chlorella pyrenoidosa

    Directory of Open Access Journals (Sweden)

    Mahender Kyadari

    2013-01-01

    Full Text Available Objective: algae isolates obtained from fresh and marine resources could be one of the richest sources of novel bioactive secondary metabolites expected to have pharmaceutical significance for new drug development. This study was conducted to evaluate the antiangiogenic and antiproliferative activity of Chlorella pyrenoidosa in experimental models of angiogenesis and by MTT assay. Materials and Methods: lyophilized extract of C. pyrenoidosa was extracted using dichloromethane/methanol (2:1, concentrated and vacuum evaporated to obtain the dried extract. The crude extract was evaluated in the vascular endothelial growth factor (VEGF-induced angiogenesis in in ovo chick chorioallantoic membrane assay (CAM at various concentrations (n = 8 using thalidomide and normal saline as positive and untreated control groups, respectively. The crude extract was also subjected to the antiangiogenic activity in the silver nitrate/potassium nitrate cautery model of corneal neovascularization (CN in rats where topical bevacizumab was used as a positive control. The vasculature was photographed and blood vessel density was quantified using Aphelion imaging software. The extract was also evaluated for its anti proliferative activity by microculture tetrazolium test (MTT assay using HeLa cancer cell line (ATCC. Results: VEGF increased the blood vessel density by 220% as compared to normal and thalidomide treatment decreased it to 67.2% in in ovo assay. In the in-vivo CN model, the mean neovascular density in the control group, the C. pyrenoidosa extract and bevacizumab group were found to be 100%, 59.02%, and 32.20%, respectively. The Chlorella pyrenoidosa extract negatively affected the viability of HeLa cells. An IC 50 value of the extract was 570 μg/ml, respectively. Conclusion: a significant antiangiogenic activity was observed against VEGF-induced neovascularization and antiproliferative activity by MTT assay. In this study, it could be attributed that the

  3. The effect of water hardness on the toxicity of uranium to a tropical freshwater alga Chlorella sp.

    Science.gov (United States)

    Charles, Amanda L; Markich, Scott J; Stauber, Jennifer L; De Filippis, Lou F

    2002-10-01

    Uranium (U) derived from mining activities is of potential ecotoxicological concern to freshwater biota in tropical northern Australia. Few data are available on the effects of water hardness (Ca and/or Mg), which is elevated in U mine wastewaters, on the toxicity and bioavailability of U to freshwater biota, particularly algae. This study determined the effect of water hardness (8, 40, 100 and 400 mg CaCO(3) x l(-1), added as calcium (Ca) and magnesium (Mg) sulphate) on the toxicity (72 h growth rate inhibition) of U to the unicellular green alga, Chlorella sp., in synthetic freshwater, at constant pH (7.0) and alkalinity (8 mg CaCO(3) x l(-1)), similar in chemical composition to sandy coastal streams in tropical northern Australia. A 50-fold increase in water hardness resulted in a 5-fold decrease (Phardness includes: (i) competition between U and Ca and/or Mg for binding sites on the cell surface; and (ii) a change in U speciation, and hence, bioavailability. Results showed that extracellular (cell-surface) and intracellular U concentrations significantly (Phardness increased from 8 to 400 mg CaCO(3)x l(-1). Calculation of U speciation using the geochemical model HARPHRQ showed that there were no significant (P>0.05) differences in the predicted speciation (% distribution) of U amongst the four water hardness levels. The reduction in U toxicity with increasing water hardness was most likely due to competition between U and Ca and/or Mg for binding sites on the algal cell surface. The minimum detectable effect concentrations of U were approximately 3 and 24 times higher (at 8 and 400 mg CaCO(3)x l(-1) hardness, respectively) than the national interim U guideline value (0.5 micro g x l(-1)) for protecting aquatic ecosystems. Overall, the results reinforce the need for a more flexible U guideline based on a hardness-dependent algorithm, which may allow environmental managers to relax the national guideline for U on a site-specific basis.

  4. Growth and Metabolism of the Green Alga, Chlorella Pyrenoidosa, in Simulated Microgravity

    Science.gov (United States)

    Mills, W. Ronald

    2003-01-01

    The effect of microgravity on living organisms during space flight has been a topic of interest for some time, and a substantial body of knowledge on the subject has accumulated. Despite this, comparatively little information is available regarding the influence of microgravity on algae, even though it has been suggested for long duration flight or occupancy in space that plant growth systems, including both higher plants and algae, are likely to be necessary for bioregenerative life support systems. High-Aspect-Ratio Rotating-Wall Vessel or HARV bioreactors developed at Johnson Space Center provide a laboratory-based approach to investigating the effects of microgravity on cellular reactions. In this study, the HARV bioreactor was used to examine the influence of simulated microgravity on the growth and metabolism of the green alga, Chlorella pyrenoidosa. After the first 2 days of culture, cell numbers increased more slowly in simulated microgravity than in the HARV gravity control; after 7 days, growth in simulated microgravity was just over half (58%) that of the gravity control and at 14 days it was less than half (42%). Chlorophyll and protein were also followed as indices of cell competence and function; as with growth, after 2-3 days, protein and chlorophyll levels were reduced in modeled microgravity compared to gravity controls. Photosynthesis is a sensitive biochemical index of the fitness of photosynthetic organisms; thus, CO2-dependent O2 evolution was tested as a measure of photosynthetic capacity of cells grown in simulated microgravity. When data were expressed with respect to cell number, modeled microgravity appeared to have little effect on CO2 fixation. Thus, even though the overall growth rate was lower for cells cultured in microgravity, the photosynthetic capacity of the cells appears to be unaffected. Cells grown in simulated microgravity formed loose clumps or aggregates within about 2 days of culture, with aggregation increasing over time

  5. On the uptake and binding of uranium (VI) by the green alga Chlorella Vulgaris; Zur Aufnahme und Bindung von Uran(VI) durch die Gruenalge Chlorella Vulgaris

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, Manja

    2011-07-01

    Uranium could be released into the environment from geogenic deposits and from former mining and milling areas by weathering and anthropogenic activities. The elucidation of uranium behavior in geo- and biosphere is necessary for a reliable risk assessment of radionuclide migration in the environment. Algae are widespread in nature and the most important group of organisms in the aquatic habitat. Because of their ubiquitous occurrence in nature the influence of algae on the migration process of uranium in the environment is of fundamental interest e.g. for the development of effective and economical remediation strategies for contaminated waters. Besides, algae are standing at the beginning of the food chain and play an economically relevant role as food and food additive. Therefore the transfer of algae-bound uranium along the food chain could arise to a serious threat to human health. Aim of this work was the quantitative and structural characterization of the interaction between U(VI) and the green alga Chlorella vulgaris in environmental relevant concentration and pH range with special emphasis on metabolic activity. Therefore a defined medium was created which assures the survival/growth of the algae as well as the possibility to predict the uranium speciation. The speciation of uranium in the mineral medium was calculated and experimentally verified by time-resolved laser-induced fluorescence spectroscopy (TRLFS). The results of the sorption experiments showed that both metabolic active and inactive algal cells bind uranium in significant amounts of around 14 mg U/g dry biomass and 28 mg U/g dry biomass, respectively. Another interesting observation was made during the growth of Chlorella cells in mineral medium at the environmental relevant uranium concentration of 5 {mu}M. Under these conditions and during ongoing cultivation a mobilization of the algae-bound uranium occurred. At higher uranium concentrations this effect was not observed due to the die off

  6. Treatment of African catfish, Clarias gariepinus wastewater utilizing phytoremediation of microalgae, Chlorella sp. with Aspergillus niger bio-harvesting.

    Science.gov (United States)

    Nasir, Nurfarahana Mohd; Bakar, Nur Syuhada Abu; Lananan, Fathurrahman; Abdul Hamid, Siti Hajar; Lam, Su Shiung; Jusoh, Ahmad

    2015-08-01

    This study focuses on the evaluation of the performance of Chlorella sp. in removing nutrient in aquaculture wastewater and its correlation with the kinetic growth of Chlorella sp. The treatment was applied with various Chlorella sp. inoculation dosage ranging from 0% to 60% (v/v) of wastewater. The optimum inoculation dosage was recorded at 30% (v/v) with effluent concentration of ammonia and orthophosphate recording at 0.012mgL(-1) and 0.647mgL(-1), respectively on Day 11. The optimum dosage for bio-flocculation process was obtained at 30mgL(-1) of Aspergillus niger with a harvesting efficiency of 97%. This type of development of phytoremediation with continuous bio-harvesting could promote the use of sustainable green technology for effective wastewater treatment.

  7. Phosphorus availability changes chromium toxicity in the freshwater alga Chlorella vulgaris.

    Science.gov (United States)

    Qian, Haifeng; Sun, Zhengqi; Sun, Liwei; Jiang, Yifeng; Wei, Yong; Xie, Jun; Fu, Zhengwei

    2013-10-01

    Chromium (Cr) is one of the most serious pollutants in aquatic systems. This study examined the relationship between the toxic effects of Cr on the freshwater alga Chlorella vulgaris and phosphorus (P) availability on the algal physiology and ultrastructure. Cr inhibited C. vulgaris growth in a concentration- and time-dependent manner, and its inhibitory effect was related to the P concentration. In a low-P medium, Cr showed approximately 2.2-3.7-fold stronger toxicity than in a high-P medium. Cr was absorbed into the algal body where it disrupted the chloroplast structure and decreased the chlorophyll content. However, Cr had a weaker chlorophyll inhibitory ability and destructive power against the chloroplasts in the high-P medium than in the low-P medium due to the partial blockage of Cr absorption in high P-medium. Cr exposure also changed the metal ion and anion absorption profiles, which was also closely related to the concentration of P. Cr treatment increased the volume of the vacuole, and the larger vacuole reduced the space available for chloroplasts, as based on optical and electron microscopy results, but a higher P availability could alleviate this damage. These results suggest that high P alleviated the toxicity of Cr by decreasing Cr absorption and increasing the absorption of beneficial ions. It is, therefore, necessary to consider the phosphorus availability when the toxicity of metal compounds is evaluated.

  8. Response of the freshwater Alga chlorella vulgaris to trichloroisocyanuric acid and ciprofloxacin.

    Science.gov (United States)

    Nie, Xiangping; Wang, Xiang; Chen, Jufang; Zitko, Vladimir; An, Taichen

    2008-01-01

    The effects of trichloroisocyanuric acid (TCCA) and ciprofloxacin (CPFX) on the freshwater alga Chlorella vulgaris were assessed by toxicity bioassays and by the values of biomarkers in phase I and phase II. The biomarkers included growth rate, concentration of chlorophyll a, activities of 7-ethoxyresorufin-O-dealkylases (EROD), glutathione S-transferase (GST), catalase (CAT), and total glutathione (GSH). Ciprofloxacin was a weaker growth inhibitor than TCCA but, at a concentration of greater than 12.5 mg/L, decreased the growth of C. vulgaris. Concentration of chlorophyll a showed a similar trend. The 96-h median effective concentration (EC50; i.e., 50% reduction in growth relative to the control) of CPFX was 20.6 mg/L. Trichloroisocyanuric acid was a strong growth inhibitor and, at concentrations of greater than 0.80 mg/L, caused 100% inhibition on 24-h exposure. The 96-h EC50 of TCCA was 0.313 mg/L. Ciprofloxacin and TCCA affected the phase I and phase II enzyme activities differently. On exposure to CPFX, both EROD and GSH decreased at low CPFX concentrations (12.5 mg/L), and CAT and GST exhibited induction at low concentrations and inhibition at high concentrations. In TCCA exposure, GST activity was significantly stimulated, and GSH concentration was increased. Catalase activity increased only at TCCA concentrations of greater than 0.12 mg/L, and no change in EROD activity was observed.

  9. Alkaline shift effect on the uptake of germanium by algae, Chlorella ellipsoideae, Oscillatoria sp. and Spirulina platensis

    Energy Technology Data Exchange (ETDEWEB)

    Yanagimoto, M. (National Food Research Inst., Ibaraki, Japan); Saitoh, H.; Kakimoto, N.

    1983-01-01

    The uptake of germanium (Ge) by microalgae was interesting because of a therapeutic effect of organic germanium. In the case of blue green algae, Oscillatoria sp. and Spirulina platensis, satisfactory amounts of Ge were accumulated in the cells, where the pH of the culture was shifted to 11.8 or 12.3, after sufficient growth. These algae could hardly grow in a culture at pH 11.8 or pH 12.3. In the case of Chlorella ellipsoideae, a good result could not be obtained. But a relatively high uptake of Ge into the cells could be obtained in the culture shifted to pH 8.6, in which the alga could hardly grow. Although the effective pHs are different, the effect of the elevated pH of the cultures can be called an alkaline shift effect from the same feature.

  10. Optimising the bioreceptivity of porous glass tiles based on colonization by the alga Chlorella vulgaris

    Energy Technology Data Exchange (ETDEWEB)

    Ferrándiz-Mas, V., E-mail: v.ferrandiz@imperial.ac.uk [Department of Civil and Environmental Engineering, Imperial College London, London SW7 2BU (United Kingdom); Bond, T., E-mail: t.bond@imperial.ac.uk [Department of Civil and Environmental Engineering, Imperial College London, London SW7 2BU (United Kingdom); Zhang, Z., E-mail: zhen.zhang14@imperial.ac.uk [Department of Civil and Environmental Engineering, Imperial College London, London SW7 2BU (United Kingdom); Melchiorri, J., E-mail: jpmelchiorri@gmail.com [ARBOREA Research, Bessemer Building, Prince Consort Road, London SW7 2AZ (United Kingdom); Cheeseman, C.R., E-mail: c.cheeseman@imperial.ac.uk [Department of Civil and Environmental Engineering, Imperial College London, London SW7 2BU (United Kingdom)

    2016-09-01

    Green façades on buildings can mitigate greenhouse gas emissions. An option to obtain green facades is through the natural colonisation of construction materials. This can be achieved by engineering bioreceptive materials. Bioreceptivity is the susceptibility of a material to be colonised by living organisms. The aim of this research was to develop tiles made by sintering granular waste glass that were optimised for bioreceptivity of organisms capable of photosynthesis. Tiles were produced by pressing recycled soda-lime glass with a controlled particle size distribution and sintering compacted samples at temperatures between 680 and 740 °C. The primary bioreceptivity of the tiles was evaluated by quantifying colonisation by the algae Chlorella vulgaris (C. vulgaris), which was selected as a model photosynthetic micro-organism. Concentrations of C. vulgaris were measured using chlorophyll-a extraction. Relationships between bioreceptivity and the properties of the porous glass tile, including porosity, sorptivity, translucency and pH are reported. Capillary porosity and water sorptivity were the key factors influencing the bioreceptivity of porous glass. Maximum C. vulgaris growth and colonisation was obtained for tiles sintered at 700 °C, with chlorophyll-a concentrations reaching up to 11.1 ± 0.4 μg/cm{sup 2} of tile. Bioreceptivity was positively correlated with sorptivity and porosity and negatively correlated with light transmittance. The research demonstrates that the microstructure of porous glass, determined by the processing conditions, significantly influences bioreceptivity. Porous glass tiles with high bioreceptivity that are colonised by photosynthetic algae have the potential to form carbon-negative façades for buildings and green infrastructure. - Highlights: • Porous tiles made by sintering waste glass at variable temperatures • Bioreceptivity assessed by measuring colonisation by the algae C. vulgaris • Tiles sintered at 700 °C gave

  11. Lipids, fatty acids composition and carotenoids of Chlorella vulgaris cultivated in hydroponic wastewater

    Directory of Open Access Journals (Sweden)

    Barcelos Oliveira, Jorge Luiz

    2006-09-01

    Full Text Available Alternative culture media have been evaluated for the cultivation of microalgae, among them are, industrial and agriculture wastewaters, that make residue recycling possible by bioconverting it into a rich, nourishing biomass that can be used as a feeding complement in aquaculture and in diverse areas. The objective of this research is to determine the lipid, fatty acid profile and carotenoid produced by the microalgae Chlorella vulgaris cultivated in a hydroponic wastewater, with different dilutions. The results showed that lipid contents did not present significant differences. Fatty acids were predominantly 16:0, 18:0, 18:1 and 18:3n-6. For total carotenoids, the dilution of hydroponic wastewater did not stimulate the production of these pigments. From this study, it was determined that, the use of hydroponic wastewater as an alternative culture medium for  the cultivation of Chlorella vulgaris generates good perspectives for lipid, fatty acid and carotenoid production.Medios de cultivo alternativos vienen siendo evaluados para el cultivo de microalgas, entre ellos, están los afluentes industriales y agrícolas, que posibilitan la reciclaje del residuo, bioconvirtiéndose en una biomasa enriquecida bajo el punto de vista nutricional, que puede ser utilizada como complemento alimenticio, para la acuacultura y en varias otras áreas de actuación. El presente trabajo tuvo como objetivo determinar los contenidos de lípidos, composición de ácidos grasos y carotenoides producidos por la microalga Chlorella vulgaris cultivada en solución hidropónica residual, con diferentes diluciones. Los resultados de los contenidos de lípidos totales no presentaron diferencia significativa. Los ácidos grasos predominantes fueron los 16:0, 18:0, 18:1 e 18:3n-6. Para los carotenoides totales, la dilución de la solución hidropónica residual no estimuló la producción de estos pigmentos por la microalga. La utilización de la solución hidrop

  12. Effect of vanadium on growth, chlorophyll formation and iron metabolism in unicellular green algae. [Chlorella pyrenoidosa; Chlorella vulgaris mutants Scenedesmus obliquus

    Energy Technology Data Exchange (ETDEWEB)

    Meisch, H.U.; Bielig, H.J.

    1975-01-01

    In presence of vanadium, growth of Scenedesmus obliquus and Chlorella pyrenoidosa was increased five to sixfold as determined by dry weight, when cultured under autotrophic conditions for 7 days. The stimulation by vanadium decreased with increasing stability towards hydrolysis of the iron(III)-compounds added. Pentavalent vanadium (20 ..mu..g V/l as NH/sub 4/ VO/sub 3/) was able to overcome completely a limited iron-deficiency in the algae following growth in presence of 1.8 x 10/sup -5/ m ferric chloride. Vanadium did not alter the iron uptake into the algal cells. 90% of offered /sup 48/V was taken up by Scenedesmus obliquus during 5 days of growth, and 21% thereof were found in the chloroplast fraction. In presence of vanadium, the chlorophyll formation was stimulated in Scenedesmus obliquus. This stimulation by vanadium was found to be light-dependent but occurred to a certain extent in the dark also. The main porphyrin of the yellow mutant 211-11h/20 of Chlorella vulgaris was identified as protoporphyrin-IX. The formation of this compound was stimulated by vanadium in the biosynthesis of chlorophylls is discussed. 18 references, 2 figures, 6 tables.

  13. Application of ozonated piggery wastewater for cultivation of oil-rich Chlorella pyrenoidosa.

    Science.gov (United States)

    Gan, Ke; Mou, Xiaoqing; Xu, Yan; Wang, Haiying

    2014-11-01

    Ozonated and autoclaved piggery wastewaters were compared for cultivation of oil-rich Chlorella pyrenoidosa by measuring nutrient removal from the medium and growth rate and lipid production of the microalgae. The removal rates of chemical oxygen demand, NH4(+)-N, total nitrogen and total phosphorus by C. pyrenoidosa were not influenced by both sterilisation methods. The specific growth rate and biomass of C. pyrenoidosa were determined by analysing the chlorophyll concentration for eliminating the disturbance of bacteria growth in culture system. Bacteria raised from the residue in the ozonated medium achieved 30% of the total microorganisms at the end of cultivation. They reduced the growth of C. pyrenoidosa by 10.4%, but contributed to a faster decline of the nutrient content on the first day. Lipid production and fatty acid profile did not change markedly in both sterilisation methods. The results suggest that ozonation is acceptable for piggery wastewater treatment for C. pyrenoidosa cultivation.

  14. Single and mixture toxicity of pharmaceuticals and chlorophenols to freshwater algae Chlorella vulgaris.

    Science.gov (United States)

    Geiger, Elisabeth; Hornek-Gausterer, Romana; Saçan, Melek Türker

    2016-07-01

    Organisms in the aquatic environment are exposed to a variety of substances of numerous chemical classes. The unintentional co-occurrence of pharmaceuticals and other contaminants of emerging concern may pose risk to non-target organisms. In this study, individual and binary mixture toxicity experiments of selected pharmaceuticals (ibuprofen and ciprofloxacin) and chlorophenols (2.4-dichlorophenol (2,4-DCP) and 3-chlorophenol (3-CP)) have been performed with freshwater algae Chlorella vulgaris. All experiments have been carried out according to the 96-h algal growth inhibition test OECD No. 201. Binary mixture tests were conducted using proportions of the respective IC50s in terms of toxic unit (TU). The mixture concentration-response curve was compared to predicted effects based on both the concentration addition (CA) and the independent action (IA) model. Additionally, the Combination Index (CI)-isobologram equation method was used to assess toxicological interactions of the binary mixtures. All substances individually tested had a significant effect on C. vulgaris population density and revealed IC50 values ciprofloxacin>3-CP>ibuprofen. Generally, it can be concluded from this study that toxic mixture effects of all tested chemicals to C. vulgaris are higher than the individual effect of each mixture component. It could be demonstrated that IC50 values of the tested mixtures predominately lead to additive effects. The CA model is appropriate to estimate mixture toxicity, while the IA model tends to underestimate the joint effect. The CI-isobologram equation method predicted the mixtures accurately and elicited synergism at low effect levels for the majority of tested combinations.

  15. The influence of extracellular compounds produced by selected Baltic cyanobacteria, diatoms and dinoflagellates on growth of green algae Chlorella vulgaris

    Science.gov (United States)

    Żak, Adam; Kosakowska, Alicja

    2015-12-01

    Secondary metabolites produced by bacteria, fungi, algae and plants could affect the growth and development of biological and agricultural systems. This natural process that occurs worldwide is known as allelopathy. The main goal of this work was to investigate the influence of metabolites obtained from phytoplankton monocultures on the growth of green algae Chlorella vulgaris. We selected 6 species occurring in the Baltic Sea from 3 different taxonomic groups: cyanobacteria (Aphanizomenon flos-aquae; Planktothrix agardhii), diatoms (Thalassiosira pseudonana; Chaetoceros wighamii) and dinoflagellates (Alexandrium ostenfeldii; Prorocentrum minimum). In this study we have demonstrated that some of selected organisms caused allelopathic effects against microalgae. Both the negative and positive effects of collected cell-free filtrates on C. vulgaris growth, chlorophyll a concentration and fluorescence parameters (OJIP, QY, NPQ) have been observed. No evidence has been found for the impact on morphology and viability of C. vulgaris cells.

  16. Selenium accumulation in unicellular green alga Chlorella vulgaris and its effects on antioxidant enzymes and content of photosynthetic pigments.

    Directory of Open Access Journals (Sweden)

    Xian Sun

    Full Text Available The aim of the present study was to investigate selenite effects in the unicellular green algae Chlorella vulgaris as a primary producer and the relationship with intracellular bioaccumulation. The effects of selenite were evaluated by measuring the effect of different selenite concentrations on algal growth during a 144 h exposure period. It was found that lower Se concentrations (≤ 75 mg L(-1 positively promoted C. vulgaris growth and acted as antioxidant by inhibiting lipid peroxidation (LPO and intracellular reactive oxygen species (ROS. The antioxidative effect was associated with an increase in guaiacol peroxidase (GPX, catalase (CAT, superoxide dismutase (SOD and photosynthetic pigments. Meanwhile, significant increase in the cell growth rate and organic Se content was also detected in the algae. In contrast, these changes were opposite in C. vulgaris exposed to Se higher than 100 mg L-1. The antioxidation and toxicity appeared to be correlated to Se bioaccumulation, which suggests the appropriate concentration of Se in the media accumulation of C. vulgaris should be 75 mg L-1. Taken together, C. vulgaris possesses tolerance to Se, and Se-Chlorella could be developed as antioxidative food for aquaculture and human health.

  17. THE EFFECT OF BIOMASS FROM GREEN ALGAE OF CHLORELLA GENUS ON THE BIOCHEMICAL CHARACTERISTICS OF TABLE EGGS

    Directory of Open Access Journals (Sweden)

    SVETLANA GRIGOROVA

    2006-10-01

    Full Text Available An analysis was made of the fatty-acid content of the dry biomass from green algae of Chlorella genus cultivated in Bulgaria, with the aim of establishing its effect on the content of total lipids, cholesterol, phospholipids and the fattyacid content of the table eggs. The fatty-acid composition of the dry biomass from green microalgae of Chlorella genus was characterized by its high content of α linolenic acid – 36,5 %, palmitic acid – 20,4 %, linoleic acid – 15 % and oleic acid – 10,3 % of the total amount of fatty acids in the product. Omega-3/Omega-6 fatty acids ratio in the biomass was 0,4. When adding 2 % and 10 % of alga biomass to the forage for the laying hens the total cholesterol content in 100 g of yolk decreased in the experimental groups compared to the control one, however, the differences were statistically insignifi cant. The supplement of 2 % and 10 % of the studied product exerted an effect on the fatty-acid content of the egg yolk and it led to the increase of the amount of palmitic and linoleic acids and to the decrease of the docosatetraenic acid.

  18. Widespread green algae Chlorella and Stichococcus exhibit polar-temperate and tropical-temperate biogeography.

    Science.gov (United States)

    Hodač, Ladislav; Hallmann, Christine; Spitzer, Karolin; Elster, Josef; Faßhauer, Fabian; Brinkmann, Nicole; Lepka, Daniela; Diwan, Vaibhav; Friedl, Thomas

    2016-08-01

    Chlorella and Stichococcus are morphologically simple airborne microalgae, omnipresent in terrestrial and aquatic habitats. The minute cell size and resistance against environmental stress facilitate their long-distance dispersal. However, the actual distribution of Chlorella- and Stichococcus-like species has so far been inferred only from ambiguous morphology-based evidence. Here we contribute a phylogenetic analysis of an expanded SSU and ITS2 rDNA sequence dataset representing Chlorella- and Stichococcus-like species from terrestrial habitats of polar, temperate and tropical regions. We aim to uncover biogeographical patterns at low taxonomic levels. We found that psychrotolerant strains of Chlorella and Stichococcus are closely related with strains originating from the temperate zone. Species closely related to Chlorella vulgaris and Muriella terrestris, and recovered from extreme terrestrial environments of polar regions and hot deserts, are particularly widespread. Stichococcus strains from the temperate zone, with their closest relatives in the tropics, differ from strains with the closest relatives being from the polar regions. Our data suggest that terrestrial Chlorella and Stichococcus might be capable of intercontinental dispersal; however, their actual distributions exhibit biogeographical patterns.

  19. Plant based phosphorus recovery from wastewater via algae and macrophytes.

    Science.gov (United States)

    Shilton, Andrew N; Powell, Nicola; Guieysse, Benoit

    2012-12-01

    At present, resource recovery by irrigation of wastewater to plants is usually driven by the value of the water resource rather than phosphorus recovery. Expanded irrigation for increased phosphorus recovery may be expected as the scarcity and price of phosphorus increases, but providing the necessary treatment, storage and conveyance comes at significant expense. An alternative to taking the wastewater to the plants is instead to take the plants to the wastewater. Algal ponds and macrophyte wetlands are already in widespread use for wastewater treatment and if harvested, would require less than one-tenth of the area to recover phosphorus compared to terrestrial crops/pastures. This area could be further decreased if the phosphorus content of the macrophytes and algae biomass was tripled from 1% to 3% via luxury uptake. While this and many other opportunities for plant based recovery of phosphorus exist, e.g. offshore cultivation, much of this technology development is still in its infancy. Research that enhances our understanding of how to maximise phosphorus uptake and harvest yields; and further add value to the biomass for reuse would see the recovery of phosphorus via plants become an important solution in the future.

  20. AlgaeSim: a model for integrated algal biofuel production and wastewater treatment.

    Science.gov (United States)

    Drexler, Ivy L C; Joustra, Caryssa; Prieto, Ana; Bair, Robert; Yeh, Daniel H

    2014-02-01

    AlgaeSim, a dynamic multiple-systems (C, N, P) mass balance model, was developed to explore the potential for algae biomass production from wastewater by coupling two photobioreactors into the main treatment train at a municipal wastewater resource recovery facility (WRRF) in Tampa, Florida. The scoping model examined the synergy between algae cultivation and wastewater treatment through algal growth and substrate removal kinetics, as well as through macroeconomic analyses of biomass conversion to bioproducts. Sensitivity analyses showed that biomass production is strongly dependent on Monod variables and harvesting regime, with sensitivity changing with growth phase. Profitability was sensitive to processing costs and market prices of products. Under scenarios based on current market conditions and typical algae production, AlgaeSim shows that a WRRF can potentially generate significant profit if algae are processed for biodiesel, biogas, or fertilizer. Wastewater resource recovery facilities could similarly save on operating costs resulting from the reduction in aeration (for nitrification) and chemicals (for denitrification).

  1. Mixotrophic growth and biochemical analysis of Chlorella vulgaris cultivated with diluted monosodium glutamate wastewater.

    Science.gov (United States)

    Ji, Yan; Hu, Wenrong; Li, Xiuqing; Ma, Guixia; Song, Mingming; Pei, Haiyan

    2014-01-01

    Monosodium glutamate wastewater (MSGW) is a potential medium for microbial cultivation because of containing abundant organic nutrient. This paper seeks to evaluate the feasibility of growing Chlorella vulgaris with MSGW and assess the influence of MSGW concentration on the biomass productivity and biochemical compositions. The MSGW diluted in different concentrations was prepared for microalga cultivation. C. vulgaris growth was greatly promoted with MSGW compared with the inorganic BG11 medium. C. vulgaris obtained the maximum biomass concentration (1.02 g/L) and biomass productivity (61.47 mg/Ld) with 100-time diluted MSGW. The harvested biomass was rich in protein (36.01-50.64%) and low in lipid (13.47-25.4%) and carbohydrate (8.94-20.1%). The protein nutritional quality and unsaturated fatty acids content of algal increased significantly with diluted MSGW. These results indicated that the MSGW is a feasible alternative for mass cultivation of C. vulgaris.

  2. Saline wastewater treatment by Chlorella vulgaris with simultaneous algal lipid accumulation triggered by nitrate deficiency.

    Science.gov (United States)

    Shen, Qiao-Hui; Gong, Yu-Peng; Fang, Wen-Zhe; Bi, Zi-Cheng; Cheng, Li-Hua; Xu, Xin-Hua; Chen, Huan-Lin

    2015-10-01

    Chlorella vulgaris, a marine microalgae strain adaptable to 0-50 g L(-1) of salinity, was selected for studying the coupling system of saline wastewater treatment and lipid accumulation. The effect of total nitrogen (T N) concentration was investigated on algal growth, nutrients removal as well as lipid accumulation. The removal efficiencies of TN and total phosphorus (TP) were found to be 92.2-96.6% and over 99%, respectively, after a batch cultivation of 20 days. To illustrate the response of lipid accumulation to nutrients removal, C. vulgaris was further cultivated in the recycling experiment of tidal saline water within the photobioreactor. The lipid accumulation was triggered upon the almost depletion of nitrate (<5 mg L(-1)), till the final highest lipid content of 40%. The nitrogen conversion in the sequence of nitrate, nitrite, and then to ammonium in the effluents was finally integrated with previous discussions on metabolic pathways of algal cell under nitrogen deficiency.

  3. Identity and physiology of a new psychrophilic eukaryotic green alga, Chlorella sp., strain BI, isolated from a transitory pond near Bratina Island, Antarctica

    Science.gov (United States)

    Morgan-Kiss, R. M.; Ivanov, A.G.; Modla, S.; Czymmek, K.; Huner, N.P.A.; Priscu, J.C.; Lisle, J.T.; Hanson, T.E.

    2008-01-01

    Permanently low temperature environments are one of the most abundant microbial habitats on earth. As in most ecosystems, photosynthetic organisms drive primary production in low temperature food webs. Many of these phototrophic microorganisms are psychrophilic; however, functioning of the photosynthetic processes of these enigmatic psychrophiles (the 'photopsychrophiles') in cold environments is not well understood. Here we describe a new chlorophyte isolated from a low temperature pond, on the Ross Ice Shelf near Bratina Island, Antarctica. Phylogenetic and morphological analyses place this strain in the Chlorella clade, and we have named this new chlorophyte Chlorella BI. Chlorella BI is a psychrophilic species, exhibiting optimum temperature for growth at around 10??C. However, psychrophily in the Antarctic Chlorella was not linked to high levels of membrane-associated poly-unsaturated fatty acids. Unlike the model Antarctic lake alga, Chlamydomonas raudensis UWO241, Chlorella BI has retained the ability for dynamic short term adjustment of light energy distribution between photosystem II (PS II) and photosystem I (PS I). In addition, Chlorella BI can grow under a variety of trophic modes, including heterotrophic growth in the dark. Thus, this newly isolated photopsychrophile has retained a higher versatility in response to environmental change than other well studied cold-adapted chlorophytes. ?? 2008 Springer.

  4. First report of Pseudobodo sp, a new pathogen for a potential energy-producing algae: Chlorella vulgaris cultures.

    Directory of Open Access Journals (Sweden)

    Zhangran Chen

    Full Text Available Chlorella vulgaris, is a kind of single-celled green algae, which could serve as a potential source of food and energy because of its photosynthetic efficiency. In our study, a pathogenic organism targeting C. vulgaris was discovered. The algae-lytic activity relates to a fraction from lysates of infected C. vulgaris that was blocked upon filtration through a 3 µm filter. 18S rRNA gene sequence analysis revealed that it shared 99.0% homology with the protist Pseudobodo tremulans. Scanning electron microscope analysis showed that Pseudobodo sp. KD51 cells were approximately 4-5 µm long, biflagellate with an anterior collar around the anterior part of the cell in unstressed feeding cells. Besides the initial host, Pseudobodo sp. KD51 could also kill other algae, indicating its relatively wide predatory spectrum. Heat stability, pH and salinity tolerance experiments were conducted to understand their effects on its predatory activities, and the results showed that Pseudobodo sp. KD51 was heat-sensitive, and pH and salinity tolerant.

  5. Effect of sorbed and desorbed Zn(Ⅱ) on the growth of a green alga (Chlorella pyrenoidosa)

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Toxic effect of Zn(Ⅱ) on a green alga (Chlorella pyrenoidasa) in the presence of sepiolite and kaolinite was investigated.The Zn-free clays were found to have a negative impact on the growth of C.pyrenoidosa in comparison with control samples (without adding any clay or Zn(Ⅱ)).When Zn(Ⅱ) was added,the algae in the presence of clays could be better survived than the control samples,which was actually caused by a decrease in Zn(Ⅱ) concentration in the solution owing to the adsorption of Zn(Ⅱ) on the clays.When the solution system was diluted,the growth of algae could be further inhibited as compared to that in a system which had the same initial Zn(Ⅱ) concentration as in the diluted system.This in fact resulted from desorption of Zn(Ⅱ) from the zinc-contaminated clays,although the effect varied according to the different desorption capabilities of sepiolite and kaolinite.Therefore the adsorption and desorption processes of Zn(Ⅱ) played an important part in its toxicity,and adsorption and desorption of pollutants on soils/sediments should be well considered in natural eco-environmental systems before their risk of toxicity to aquatic organisms was assessed objectively.

  6. Molecular study of the chlorella algae and determining its functional features with the approach of hydrogenase gene expression

    Directory of Open Access Journals (Sweden)

    Seyedeh Tayebeh Mousavi

    2016-09-01

    Full Text Available Biohydrogen production by biological processes are known as a renewable energy source. The aim of the investigation was to find and optimize the most appropriate medium for the algae growth to produce the maximum amount of hydrogen. First of all, the bioinformatics and biosystematics studies were taken for identifying the collected microalgae which was detected as Chlorella with the following features: spherical appearance, spent protozoan, Cup-shaped chloroplast with no flagella. On the other hand, the molecular analysis by PCR and 18S sequence typing of interested microalgae demonstrated 100% similarity to that well known sequences for Chlorella vulgaris. Second, we assessed some culture media including BBM, Chu10, TAP, and Sorokin and Krauss for optimum growth conditions for Chlorella vulgaris. In general, our results showed that BBM medium had the highest efficiency for producing microalgae biomass under following conditions: pH=8, temperature of 30 ° with 16 to 8 h light to darkness periods ratio.Third, we designed a more efficient photo-bioreactor apparatus toward inducing more powerful bio-hydrogen production by hydrogenase enzyme activity of our given microalgae. Then, the performance of the apparatus as well as the gene expression was scrutinized under different conditions (light, pH, sulphorous, etc.. For this, after extracting RNA and constructing cDNA, hydrogenase gene was amplified with PCR and the product was evaluated by agarose gel. However, the relative expression of the gene measured by Real Time PCR showed the influence of light, pH and sulphourous on the expression as compared with control.

  7. Interactive effect of brassinosteroids and cytokinins on growth, chlorophyll, monosaccharide and protein content in the green alga Chlorella vulgaris (Trebouxiophyceae).

    Science.gov (United States)

    Bajguz, Andrzej; Piotrowska-Niczyporuk, Alicja

    2014-07-01

    Interaction between brassinosteroids (BRs) (brassinolide, BL; 24-epibrassinolide, 24-epiBL; 28-homobrassinolide, 28-homoBL; castasterone, CS; 24-epicastasterone, 24-epiCS; 28-homocastasterone, 28-homoCS) and adenine- (trans-zeatin, tZ; kinetin, Kin) as well as phenylurea-type (1,3-diphenylurea, DPU) cytokinins (CKs) in the regulation of cell number, phytohormone level and the content of chlorophyll, monosaccharide and protein in unicellular green alga Chlorella vulgaris (Trebouxiophyceae) were examined. Chlorella vulgaris exhibited sensitivity to CKs in the following order of their stimulating properties: 10 nM tZ > 100 nM Kin >1 μM DPU. Exogenously applied BRs possessed the highest biological activity in algal cells at concentration of 10 nM. Among the BRs, BL was characterized by the highest activity, while 28-homoCS - by the lowest. The considerable increase in the level of all endogenous BRs by 27-46% was observed in C. vulgaris culture treated with exogenous 10 nM tZ. It can be speculated that CKs may stimulate BR activity in C. vulgaris by inducing the accumulation of endogenous BRs. CKs interacted synergistically with BRs increasing the number of cells and endogenous accumulation of proteins, chlorophylls and monosaccharides in C. vulgaris. The highest stimulation of algal growth and the contents of analyzed biochemical parameters were observed for BL applied in combination with tZ, whereas the lowest in the culture treated with both 28-homoCS and DPU. However, regardless of the applied mixture of BRs with CKs, the considerable increase in cell number and the metabolite accumulation was found above the level obtained in cultures treated with any single phytohormone in unicellular green alga C. vulgaris.

  8. Temporal Eukarya, Bacteria, and Archaea biodiversity during cultivation of an alkaliphilic algae, Chlorella vulgaris, in an outdoor raceway pond

    Directory of Open Access Journals (Sweden)

    Tisza Ann Szeremy Bell

    2016-01-01

    Full Text Available Algal biofuels and valuable co-products are being produced in both open and closed cultivation systems. Growing algae in open pond systems may be a more economical alternative, but this approach allows environmental microorganisms to colonize the pond and potentially infect or outcompete the algal crop. In this study, we monitored the microbial community of an outdoor, open raceway pond inoculated with a high lipid-producing alkaliphilic alga, Chlorella vulgaris BA050. The strain C. vulgaris BA050 was previously isolated from Soap Lake, Washington, a system characterized by a high pH (approximately 9.8. An outdoor raceway pond (200L was inoculated with C. vulgaris and monitored for ten days and then the culture was transferred to a 2,000L raceway pond and cultivated for an additional six days. Community DNA samples were collected over the 16-day period in conjunction with water chemistry analyses and cell counts. Universal primers for the SSU rRNA gene sequences for Eukarya, Bacteria, and Archaea were used for barcoded pyrosequence determination. The environmental parameters that most closely correlated with C. vulgaris abundance were pH and phosphate. Community analyses indicated that the pond system remained dominated by the Chlorella population (93% of eukaryotic sequences, but was also colonized by other microorganisms. Bacterial sequence diversity increased over time while archaeal sequence diversity declined over the same time period. Using SparCC co-occurrence network analysis, a positive correlation was observed between C. vulgaris and Pseudomonas sp. throughout the experiment, which may suggest a symbiotic relationship between the two organisms. The putative relationship coupled with high pH may have contributed to the success of C. vulgaris. The characterization of the microbial community dynamics of an alkaliphilic open pond system provides significant insight into open pond systems that could be used to control photoautotrophic

  9. Continuous cultivation of Chlorella pyrenoidosa using anaerobic digested starch processing wastewater in the outdoors.

    Science.gov (United States)

    Chu, Hua-Qiang; Tan, Xiao-Bo; Zhang, Ya-Lei; Yang, Li-Bin; Zhao, Fang-Chao; Guo, Jun

    2015-06-01

    Microalgae cultivation using wastewater might be a suitable approach to support sustainable large-scale biomass production. Its compelling characteristics included the recycling of nutrients and water resources, reducing carbon emissions and harvesting available biomass. In outdoor batch and continuous cultures, Chlorella pyrenoidosa completely adapted to anaerobic digested starch processing wastewater and was the dominant microorganism in the photobioreactor. However, seasonal changes of environmental conditions significantly influenced biomass growth and lipid production. The long-term outdoor operation demonstrated that the biomass concentration and productivity in continuous operations at different hydraulic retention times (HRTs) can be successfully predicted using the kinetic growth parameters obtained from the batch culture. A moderate HRT (4days) in the summer provided the best microalgae and lipid production and achieved relatively high biomass concentrations of 1.29-1.62g/L, biomass productivities of 342.6±12.8mg/L/d and lipids productivities of 43.37±7.43mg/L/d.

  10. Promoting the Growth of Chlorella vulgaris in Secondary Wastewater Treatment Effluent of Tofu Industry using Azospirillum sp

    Directory of Open Access Journals (Sweden)

    Wahyunanto Agung Nugroho

    2016-05-01

    Full Text Available The objective of this research is to investigate the influence of growth promoting bacteria (GPB Azospirillum sp on the growth of microalgae Chlorella vulgaris in wastewater of tofu industry as a medium. To observe the influence, about 106 cells/mL of Chlorella vulgaris was cultivated in 1 L of wastewater of tofu industry. The wastewater was an effluent of an aerobic treatment. Six different treatments were set regarding to the Azospirillum sp added to the medium. The glass was marked as A0 as no GPB inoculants added to the medium, and A2, A4, A6, A8 and A10 for 2 mL, 4mL, 6mL, 8 mL and 10 mL of GPB added to the medium respectively. The concentration of GPB inoculant was 108 cfu per mL. The result showed that the highest number of Chlorella vulgaris population was achieved by addition of 6 mL GPB Azospirillum sp in the day 10, while the highest maximum growth rate was achieved by addition of 10 mL GPB Azospirillum sp  to the medium.

  11. Tolerance and nutrients consumption of Chlorella vulgaris growing in mineral medium and real wastewater under laboratory conditions

    Directory of Open Access Journals (Sweden)

    María de Lourdes Franco Martínez

    2017-02-01

    Full Text Available Microalgae have the potential of consuming high amounts of nitrogen and phosphorus from wastewater; thus, avoiding the risk of eutrophication of the water bodies. Nevertheless, ammonium can usually inhibit the growth of microalgae. Tolerance to ammonium is specific of each strain; so, the development of tertiary wastewater treatment proposals, employing microalgae, has as a first step the study of its tolerance to N-NH3. In this work, the tolerance of Chlorella vulgaris to N-NH3, using mineral medium, was studied. Afterward, C. vulgaris was used to remove nitrogen and phosphorus from a real wastewater. The maximal biomass concentration was reached at 66 ppm N-NH3 (0.49 gL-1 with the complete depletion of the ammonium and a phosphorus consumption of 2 mgPi L-1d-1 in all the experiments. When C. vulgaris was grown in real wastewater, the final biomass concentration was 0.267 g L-1 and the nutrients (N and P were totally consumed after 3 days. According with these results, this strain of Chlorella has the potential for the removal of nitrogen and phosphorus from tertiary wastewater and the biomass produced in the process can be used for the production of high value products, such as pigments, proteins, carbohydrate or used for animal feed.

  12. Cultivation of Chlorella vulgaris in wastewater with waste glycerol: Strategies for improving nutrients removal and enhancing lipid production.

    Science.gov (United States)

    Ma, Xiaochen; Zheng, Hongli; Addy, Min; Anderson, Erik; Liu, Yuhuan; Chen, Paul; Ruan, Roger

    2016-05-01

    To improve nutrients removal from wastewater and enhance lipid production, cultivation of Chlorella vulgaris in wastewater with waste glycerol generated from biodiesel production using scum derived oil as feedstock was studied. The results showed that nutrients removal was improved and lipid production of C. vulgaris was enhanced with the addition of waste glycerol into wastewater to balance its C/N ratio. The optimal concentration of the pretreated glycerol for C. vulgaris was 10gL(-1) with biomass concentration of 2.92gL(-1), lipid productivity of 163mgL(-1)d(-1), and the removal of 100% ammonia and 95% of total nitrogen. Alkaline conditions prompted cell growth and lipid accumulation of C. vulgaris while stimulating nutrients removal. The application of the integration process can lower both wastewater treatment and biofuel feedstock costs.

  13. The influence of salinity on the toxicity of selected sulfonamides and trimethoprim towards the green algae Chlorella vulgaris.

    Science.gov (United States)

    Borecka, Marta; Białk-Bielińska, Anna; Haliński, Łukasz P; Pazdro, Ksenia; Stepnowski, Piotr; Stolte, Stefan

    2016-05-05

    This paper presents the investigation of the influence of salinity variations on the toxicity of sulfapyridine, sulfamethoxazole, sulfadimethoxine and trimethoprim towards the green algae Chlorella vulgaris after exposure times of 48 and 72 h. In freshwater the EC50 values ranged from 0.98 to 123.22 mg L(-1) depending on the compound. The obtained results revealed that sulfamethoxazole and sulfapyridine were the most toxic, while trimethoprim was the least toxic pharmaceutical to the selected organism. Deviations between the nominal and real test concentrations were determined via instrumental analysis to support the interpretation of ecotoxicological data. The toxicity effects were also tested in saline water (3, 6 and 9 PSU). The tendency that the toxicity of selected pharmaceuticals decreases with increasing salinity was observed. Higher salinity implies an elevated concentration of inorganic monovalent cations that are capable of binding with countercharges available on algal surfaces (hydroxyl functional groups). Hence it can reduce the permeability of pharmaceuticals through the algal cell walls, which could be the probable reason for the observed effect. Moreover, for the classification of the mode of toxic action, the toxic ratio concept was applied, which indicated that the effects of the investigated drugs towards algae are caused by the specific mode of toxic action.

  14. Toxicity of Cu (II) to the green alga Chlorella vulgaris: a perspective of photosynthesis and oxidant stress.

    Science.gov (United States)

    Chen, Zunwei; Song, Shufang; Wen, Yuezhong; Zou, Yuqin; Liu, Huijun

    2016-09-01

    The toxic effects of Cu (II) on the freshwater green algae Chlorella vulgaris and its chloroplast were investigated by detecting the responses of photosynthesis and oxidant stress. The results showed that Cu (II) arrested the growth of C. vulgaris and presented in a concentration- and time-dependent trend and the SRichards 2 model fitted the inhibition curve best. The chlorophyll fluorescence parameters, including qP, Y (II), ETR, F v /F m , and F v /F 0, were stimulated at low concentration of Cu (II) but declined at high concentration, indicating the photosystem II (PSII) of C. vulgaris was destroyed by Cu (II). The chloroplasts were extracted, and the Hill reaction activity (HRA) of chloroplast was significantly decreased with the increasing Cu (II) concentration under both illuminating and dark condition, and faster decline speed was observed under dark condition. Activities of superoxide dismutase (SOD) and catalase (CAT) and malondialdehyde (MDA) content were also significantly decreased at high concentration Cu (II), companied with a large number of reactive oxygen species (ROS) production. All these results indicated a severe oxidative stress on algal cells occurred as well as the effect on photosynthesis, thus inhibiting the growth of algae, which providing sights to evaluate the phytotoxicity of Cu (II).

  15. The combined and second exposure effect of copper (II) and chlortetracycline on fresh water algae, Chlorella pyrenoidosa and Microcystis aeruginosa.

    Science.gov (United States)

    Lu, Lei; Wu, Yixiao; Ding, Huijun; Zhang, Weihao

    2015-07-01

    In the experiment, Chlorella pyrenoidosa and Microcystis aeruginosa were chosen to test the individual, combined and second exposure effect of Cu(2+) and chlortetracycline (CTC). The 96 h EC50s of each test were calculated, with the ranges of 0.972-15.6 μmol/L (Cu(2+)), 29.5-102.5 μmol/L (CTC), 14.4-78.9 μmol/L (mixture). The combined toxicities were evaluated with toxicity units (TU) method. The toxicity of complex of Cu(2+) and chlortetracycline was analyzed using concentration addition (CA) model. In the initial test, the combined effect of the two substances was partly additive to C. pyrenoidosa and antagonistic to M. aeruginosa, while in the second exposure test, the combined effect was synergistic to both algae. The biochemical indicators measured in the experiment included chlorophyll fluorescence (Fv/Fm), MDA content, SOD activity and content of soluble proteins. When under combined stress, the biochemical features of both algae were significantly different between the initial test and the second exposure test.

  16. Green algae (Chlorella pyrenoidosa) adsorbs Bacillus thurigiensis (Bt) toxin, Cry1Ca insecticidal protein, without an effect on growth.

    Science.gov (United States)

    Wang, Jiamei; Chen, Xiuping; Li, Yunhe; Su, Changqing; Ding, Jiatong; Peng, Yufa

    2014-08-01

    The effect of purified Cry1Ca insecticidal protein on the growth of Chlorella pyrenoidosa was studied in a three-generation toxicity test. The C. pyrenoidosa medium with a density of 5.4 × 10(5) cells/mL was subcultured for three generations with added Cry1Ca at 0, 10, 100, and 1000 µg/L, and cell numbers were determined daily. To explore the distribution of Cry1Ca in C. pyrenoidosa and the culture medium, Cry1Ca was added at 1000 µg/L to algae with a high density of 4.8 × 10(6) cells/mL, and Cry1Ca content was determined daily in C. pyrenoidosa and the culture medium by enzyme-linked immunosorbent assays. Our results showed that the growth curves of C. pyrenoidosa exposed to 10, 100, and 1000 µg/L of Cry1Ca almost overlapped with that of the blank control, and there were no statistically significant differences among the four treatments from day 0 to day 7, regardless of generation. Moreover, the Cry1Ca content in the culture medium and in C. pyrenoidosa sharply decreased under exposure of 1000 µg/L Cry1Ca with high initial C. pyrenoidosa cell density. The above results demonstrate that Cry1Ca in water can be rapidly adsorbed and degraded by C. pyrenoidosa, but it has no suppressive or stimulative effect on algae growth.

  17. Algae-based biofilm productivity utilizing dairy wastewater: effects of temperature and organic carbon concentration

    National Research Council Canada - National Science Library

    Fica, Zachary T; Sims, Ronald C

    2016-01-01

    .... The dairy industry is a significant source of wastewater worldwide that could provide an inexpensive and nutrient rich feedstock for the cultivation of algae biomass for use in downstream processing...

  18. Cultivation of Chlorella vulgaris JSC-6 with swine wastewater for simultaneous nutrient/COD removal and carbohydrate production.

    Science.gov (United States)

    Wang, Yue; Guo, Wanqian; Yen, Hong-Wei; Ho, Shih-Hsin; Lo, Yung-Chung; Cheng, Chieh-Lun; Ren, Nanqi; Chang, Jo-Shu

    2015-12-01

    Swine wastewater, containing a high concentration of COD and ammonia nitrogen, is suitable for the growth of microalgae, leading to simultaneous COD/nutrients removal from the wastewater. In this study, an isolated carbohydrate-rich microalga Chlorella vulgaris JSC-6 was adopted to perform swine wastewater treatment. Nearly 60-70% COD removal and 40-90% NH3-N removal was achieved in the mixotrophic and heterotrophic culture, depending on the dilution ratio of the wastewater, while the highest removal percentage was obtained with 20-fold diluted wastewater. Mixotrophic cultivation by using fivefold diluted wastewater resulted in the highest biomass concentration of 3.96 g/L. The carbohydrate content of the microalga grown on the wastewater can reach up to 58% (per dry weight). The results indicated that the microalgae-based wastewater treatment can efficiently reduce the nutrients and COD level, and the resulting microalgal biomass had high carbohydrate content, thereby having potential applications for the fermentative production of biofuels or chemicals.

  19. Enhanced acetyl-CoA production is associated with increased triglyceride accumulation in the green alga Chlorella desiccata.

    Science.gov (United States)

    Avidan, Omri; Brandis, Alexander; Rogachev, Ilana; Pick, Uri

    2015-07-01

    Triglycerides (TAGs) from microalgae can be utilized as food supplements and for biodiesel production, but little is known about the regulation of their biosynthesis. This work aimed to test the relationship between acetyl-CoA (Ac-CoA) levels and TAG biosynthesis in green algae under nitrogen deprivation. A novel, highly sensitive liquid chromatography mass spectrometry (LC-MS/MS) technique enabled us to determine the levels of Ac-CoA, malonyl-CoA, and unacetylated (free) CoA in green microalgae. A comparative study of three algal species that differ in TAG accumulation levels shows that during N starvation, Ac-CoA levels rapidly rise, preceding TAG accumulation in all tested species. The levels of Ac-CoA in the high TAG accumulator Chlorella desiccata exceed the levels in the moderate TAG accumulators Dunaliella tertiolecta and Chlamydomonas reinhardtii. Similarly, malonyl-CoA and free CoA levels also increase, but to lower extents. Calculated cellular concentrations of Ac-CoA are far lower than reported K mAc-CoA values of plastidic Ac-CoA carboxylase (ptACCase) in plants. Transcript level analysis of plastidic pyruvate dehydrogenase (ptPDH), the major chloroplastic Ac-CoA producer, revealed rapid induction in parallel with Ac-CoA accumulation in C. desiccata, but not in D. tertiolecta or C. reinhardtii. It is proposed that the capacity to accumulate high TAG levels in green algae critically depends on their ability to divert carbon flow towards Ac-CoA. This requires elevation of the chloroplastic CoA pool level and enhancement of Ac-CoA biosynthesis. These conclusions may have important implications for future genetic manipulation to enhance TAG biosynthesis in green algae.

  20. Comparison of Chlorella vulgaris and cyanobacterial biomass: cultivation in urban wastewater and methane production.

    Science.gov (United States)

    Mendez, Lara; Sialve, Bruno; Tomás-Pejó, Elia; Ballesteros, Mercedes; Steyer, Jean Philippe; González-Fernández, Cristina

    2016-05-01

    Anaerobic digestion of microalgae is hampered by its complex cell wall. Against this background, cyanobacteria cell walls render this biomass as an ideal substrate for overcoming this drawback. The aim of the present study was to compare the growth of two cyanobacteria (Aphanizomenon ovalisporum and Anabaena planctonica) and a microalga (Chlorella vulgaris) in urban wastewater when varying the temperature (22, 27 and 32 °C). Cyanobacterial optimal growth for both strains was attained at 22 °C, while C. vulgaris did not show remarkable differences among temperatures. For all the microorganisms, ammonium removal was higher than phosphate. Biomass collected was subjected to anaerobic digestion. Methane yield of C. vulgaris was 184.8 mL CH4 g COD in(-1) while with A. ovalisporum and A. planctonica the methane production was 1.2- and 1.4-fold higher. This study showed that cyanobacteria growth rates could be comparable to microalgae while presenting the additional benefit of an increased anaerobic digestibility.

  1. Effect of wastewater-borne bacteria on algal growth and nutrients removal in wastewater-based algae cultivation system.

    Science.gov (United States)

    Ma, Xiaochen; Zhou, Wenguang; Fu, Zongqiang; Cheng, Yanling; Min, Min; Liu, Yuhuan; Zhang, Yunkai; Chen, Paul; Ruan, Roger

    2014-09-01

    Centrate, a type of nutrient-rich municipal wastewater was used to determine the effect of wastewater-borne bacteria on algal growth and nutrients removal efficiency in this study. The characteristics of algal and bacterial growth profiles, wastewater nutrient removal and effect of initial algal inoculums were systematically examined. The results showed that initial algal concentration had apparent effect on bacterial growth, and the presence of bacteria had a significant influence on algal growth pattern, suggesting symbiotic relationship between algae and bacteria at the initial stage of algae cultivation. The maximum algal biomass of 2.01 g/L with 0.1g/L initial algal inoculums concentration can be obtained during algae cultivation in raw centrate medium. The synergistic effect of centrate-borne bacteria and microalgae on algae growth and nutrient removal performance at initial fast growth stage has great potential to be applied to pilot-scale wastewater-based algae wastewater system cultivated in continuous or semi-continuous mode.

  2. Streptomycin affects the growth and photochemical activity of the alga Chlorella vulgaris.

    Science.gov (United States)

    Perales-Vela, Hugo Virgilio; García, Roberto Velasco; Gómez-Juárez, Evelyn Alicia; Salcedo-Álvarez, Martha Ofelia; Cañizares-Villanueva, Rosa Olivia

    2016-10-01

    Antibiotics are increasingly being used in human and veterinary medicine, as well as pest control in agriculture. Recently, their emergence in the aquatic environment has become a global concern. The aim of this study was to evaluate the effect of streptomycin on growth and photosynthetic activity of Chlorella vulgaris after 72h exposure. We found that growth, photosynthetic activity and the content of the D1 protein of photosystem II decreased. Analysis of chlorophyll a fluorescence emission shows a reduction in the energy transfer between the antenna complex and reaction center. Also the activity of the oxygen evolution complex and electron flow between QA and QB were significantly reduced; in contrast, we found an increase in the reduction rate of the acceptor side of photosystem I. The foregoing can be attributed to the inhibition of the synthesis of the D1 protein and perhaps other coded chloroplast proteins that are part of the electron transport chain which are essential for the transformation of solar energy in the photosystems. We conclude that micromolar concentrations of streptomycin can affect growth and photosynthetic activity of Chlorella vulgaris. The accumulation of antibiotics in the environment can become an ecological problem for primary producers in the aquatic environment. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Application of nano TiO2 modified hollow fiber membranes in algal membrane bioreactors for high-density algae cultivation and wastewater polishing.

    Science.gov (United States)

    Hu, Weiming; Yin, Jun; Deng, Baolin; Hu, Zhiqiang

    2015-10-01

    Polyvinylidene fluoride (PVDF) hollow fiber membranes with nano-TiO2 (5% of PVDF by mass, average size = 25 nm) additives were fabricated and applied for high-density algae (Chlorella vulgaris) cultivation. At the average light intensity of 121 μmol/m(2)/s, the algal membrane bioreactors (A-MBR) operated at a hydraulic retention time of 0.5d and an average solids retention time of 25d had an average algae biomass concentration of 2350 ± 74 mg/L (in COD units) and algal biomass production rate of 6.5 ± 0.1g/m(2)/d. The A-MBRs removed an average of 78% of phosphorus from the wastewater at the initial total phosphorus concentrations ranging from 3.5 to 8.6 mg/L. The nano TiO2-embedded membranes had improved surface hydrophilicity with its total resistance about 50% lower than that of the control. This study demonstrated that PVDF/TiO2 nanocomposite membranes had a better antifouling property for high-density algae cultivation and wastewater polishing. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. The interactive effects of microcystin-LR and cylindrospermopsin on the growth rate of the freshwater algae Chlorella vulgaris.

    Science.gov (United States)

    Pinheiro, Carlos; Azevedo, Joana; Campos, Alexandre; Vasconcelos, Vítor; Loureiro, Susana

    2016-05-01

    Microcystin-LR (MC-LR) and cylindrospermopsin (CYN) are the most representative cyanobacterial cyanotoxins. They have been simultaneously detected in aquatic systems, but their combined ecotoxicological effects to aquatic organisms, especially microalgae, is unknown. In this study, we examined the effects of these cyanotoxins individually and as a binary mixture on the growth rate of the freshwater algae Chlorella vulgaris. Using the MIXTOX tool, the reference model concentration addition (CA) was selected to evaluate the combined effects of MC-LR and CYN on the growth of the freshwater green algae due to its conservative prediction of mixture effect for putative similar or dissimilar acting chemicals. Deviations from the CA model such as synergism/antagonism, dose-ratio and dose-level dependency were also assessed. In single exposures, our results demonstrated that MC-LR and CYN had different impacts on the growth rates of C. vulgaris at the highest tested concentrations, being CYN the most toxic. In the mixture exposure trial, MC-LR and CYN showed a synergistic deviation from the conceptual model CA as the best descriptive model. MC-LR individually was not toxic even at high concentrations (37 mg L(-1)); however, the presence of MC-LR at much lower concentrations (0.4-16.7 mg L(-1)) increased the CYN toxicity. From these results, the combined exposure of MC-LR and CYN should be considered for risk assessment of mixtures as the toxicity may be underestimated when looking only at the single cyanotoxins and not their combination. This study also represents an important step to understand the interactions among MC-LR and CYN detected previously in aquatic systems.

  5. Removal of estrone, 17alpha-ethinylestradiol, and 17beta-estradiol in algae and duckweed-based wastewater treatment systems.

    Science.gov (United States)

    Shi, Wenxin; Wang, Lizheng; Rousseau, Diederik P L; Lens, Piet N L

    2010-05-01

    Many pollutants have received significant attention due to their potential estrogenic effect and are classified as endocrine disrupting compounds (EDCs). Because of possible ecological effects and increased attention for water reuse schemes, it is important to increase our understanding of the EDC removal capacities of various wastewater treatment systems. However, there has so far been little research on the fate and behavior of EDCs in stabilization pond systems for wastewater treatment, which represent an important class of wastewater treatment systems in developing countries because of their cost-effectiveness. The aim of this work is to study the fate and behavior of EDCs in algae and duckweed ponds. Because the synthetic hormone 17alpha-ethinylestradiol (EE2) and the natural hormones estrone (E1), as well as 17beta-estradiol (E2), have been detected in effluents of sewage treatment plants and been suggested as the major compounds responsible for endocrine disruption in domestic sewage; E1, E2, and EE2 were therefore chosen as target chemicals in this current work. Both batch tests and continuous-flow tests were carried out to investigate the sorption and biodegradation of estrogens in algae and duckweed pond systems. The applied duckweed was a Lemna species. The applied algae was a mixture of pure cultures of six different algae genera, i.e., Anabaena cylindrica, Chlorococcus, Spirulina platensis, Chlorella, Scenedesmus quadricauda, and Anaebena var. Synthetic wastewater were used in all tests. The concentrations of estrogens were measured with three different enzyme-linked immunosorbent assay kits specific for E1, E2, or EE2. When the concentrations of estrogens in water samples were below the lowest quantitative analysis range (0.05 microg/l), preconcentration of the water samples were performed by means of solid phase extraction (SPE) with C18 cartridges. The 6-day batch tests show that the presence of algae or duckweed accelerated the removal of the three

  6. Cultivation of algae consortium in a dairy farm wastewater for biodiesel production

    Directory of Open Access Journals (Sweden)

    S. Hena

    2015-06-01

    Full Text Available Dairy farm wastewaters are potential resources for production of microalgae biofuels. A study was conducted to evaluate the capability of production of biodiesel from consortium of native microalgae culture in dairy farm treated wastewater. Native algal strains were isolated from dairy farm wastewaters collection tank (untreated wastewater as well as from holding tank (treated wastewater. The consortium members were selected on the basis of fluorescence response after treating with Nile red reagent. Preliminary studies of two commercial and consortium of ten native strains of algae showed good growth in wastewaters. A consortium of native strains was found capable to remove more than 98% nutrients from treated wastewater. The biomass production and lipid content of consortium cultivated in treated wastewater were 153.54 t ha−1 year−1 and 16.89%, respectively. 72.70% of algal lipid obtained from consortium could be converted into biodiesel.

  7. Azoxystrobin-induced excessive reactive oxygen species (ROS) production and inhibition of photosynthesis in the unicellular green algae Chlorella vulgaris.

    Science.gov (United States)

    Liu, Lei; Zhu, Bin; Wang, Gao-Xue

    2015-05-01

    This study investigated the short-term toxicity of azoxystrobin (AZ), one of strobilurins used as an effective fungicidal agent to control the Asian soybean rust, on aquatic unicellular algae Chlorella vulgaris. The median percentile inhibition concentration (IC₅₀) of AZ for C. vulgaris was found to be 510 μg L(-1). We showed that the algal cells were obviously depressed or shrunk in 300 and 600 μg L(-1) AZ treatments by using the electron microscopy. Furthermore, 19, 75, and 300 μg L(-1) AZ treatments decreased the soluble protein content and chlorophyll concentrations in C. vulgaris and altered the energy-photosynthesis-related mRNA expression levels in 48- and 96-h exposure periods. Simultaneously, our results showed that AZ could increase the total antioxidant capacity (T-AOC) level and compromise superoxide dismutase (SOD), peroxidase (POD), glutathione S transferase (GST), glutathione peroxidase (GPx) activities, and glutathione (GSH) content. These situations might render C. vulgaris more vulnerable to oxidative damage. Overall, the present study indicated that AZ might be toxic to the growth of C. vulgaris, affect energy-photosynthesis-related mRNA expressions, and induce reactive oxygen species (ROS) overproduction in C. vulgaris.

  8. Regeneration and maturation of daughter cell walls in the autospore-forming green alga Chlorella vulgaris (Chlorophyta, Trebouxiophyceae).

    Science.gov (United States)

    Yamamoto, Maki; Fujishita, Mariko; Hirata, Aiko; Kawano, Shigeyuki

    2004-08-01

    Cell-wall synthesis in Chlorella vulgaris, an autospore-forming alga, was observed using the cell wall-specific fluorescent dye Fluostain I. The observation suggested two clearly distinguishable stages in cell-wall synthesis: moderate synthesis during the cell-growth process and rapid synthesis at the cell-division stage. We used electron microscopy to examine the structural changes that occurred with growth in the premature daughter cell wall during the cell-growth and cell-division phases. The cell began to synthesize a new daughter cell wall shortly after its release from the autosporangium. A very thin daughter cell wall, with a thickness of about 2 nm, was formed inside the mother cell wall and completely enveloped the outer surface of the plasma membrane of the cell. The daughter cell wall gradually increased in thickness from 2 to 3.8 nm. During the protoplast-division phase in the cell-division stage, the daughter cell wall expanded on the surface of the invaginating plasma membrane of the cleavage furrow, accompanied by active synthesis of the cell wall, which increased in thickness from 3.8 to 6.1 nm. The daughter cell matured into an autospore while completely enclosed by its own thickening (from 6.1 to 17 nm) wall. Finally, the released daughter cell was enclosed by its own cell wall after the mother cell wall burst. The daughter cell with mature wall thickness (17-21 nm) emerged as a small, but complete, autospore.

  9. Nutrient removal and biodiesel production by integration of freshwater algae cultivation with piggery wastewater treatment.

    Science.gov (United States)

    Zhu, Liandong; Wang, Zhongming; Shu, Qing; Takala, Josu; Hiltunen, Erkki; Feng, Pingzhong; Yuan, Zhenhong

    2013-09-01

    An integrated approach, which combined freshwater microalgae Chlorella zofingiensis cultivation with piggery wastewater treatment, was investigated in the present study. The characteristics of algal growth, lipid and biodiesel production, and nutrient removal were examined by using tubular bubble column photobioreactors to cultivate C. zofingiensis in piggery wastewater with six different concentrations. Pollutants in piggery wastewater were efficiently removed among all the treatments. The specific growth rate and biomass productivity were different among all the cultures. As the initial nutrient concentration increased, the lipid content of C. zofingiensis decreased. The differences in lipid and biodiesel productivity of C. zofingiensis among all the treatments mainly resulted from the differences in biomass productivity. It is worthy of note that the diluted piggery wastewater with 1900 mg L(-1) COD provided an optimal nutrient concentration for C. zofingiensis cultivation, where the advantageous nutrient removal and the highest productivities of biomass, lipid and biodiesel were presented. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Biosorption characteristics of unicellular green alga Chlorella sorokiniana immobilized in loofa sponge for removal of Cr(Ⅲ)

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Loofa sponge (LS) immobilized biomass of Chlorella sorokiniana (LSIBCS), isolated from industrial wastewater, was investigated as a new biosorbent for the removal of Cr(Ⅲ) from aqueous solution. A comparison of the biosorption of Cr(Ⅲ) by LSIBCS and free biomass of C. sorokiniana (FBCS) from 10-300 mg Cr(Ⅲ)/L aqueous solutions showed an increase in uptake of 17.79% when the microalgal biomass was immobilized onto loofa sponge. Maximum biosorption capacity for LSIBCS and FBCS was found to be 69.26 and 58.80 mg Cr(Ⅲ)/g biosorbent, respectively, whereas the amount of Cr(Ⅲ) ions adsorbed onto naked LS was 4.97 mg/g. The kinetics of Cr(Ⅲ) biosorption was extremely rapid and equilibrium was established in about 15 and 20 min by LSIBCS and FBCS,respectively. The biosorption equilibrium was well defined by Langmuir adsorption isotherm model. The biosorption kinetics followed the pseudo-second order kinetic model. The biosorption was found to be pH dependent and the maximum sorption occurred at the solution pH 4.0. Desorption studies showed that 98% of the adsorbed Cr(Ⅲ) could be desorbed with 0.1 mol/L HNO3, while other desorbing agents were less effective in the order: EDTA > H2SO4 > CH3COOH > HCl. The regenerated LSIBCS retained 92.68% of the initial Cr(Ⅲ) binding capacity up to five cycles of reuse in continuous flow-fixed bed columns. The study revealed that LSIBCS could be used as an effective biosorbent for the removal of Cr(Ⅲ) from wastewater.

  11. The laboratory environmental algae pond simulator (LEAPS) photobioreactor: Validation using outdoor pond cultures of Chlorella sorokiniana and Nannochloropsis salina

    Energy Technology Data Exchange (ETDEWEB)

    Huesemann, M.; Williams, P.; Edmundson, S.; Chen, P.; Kruk, R.; Cullinan, V.; Crowe, B.; Lundquist, T.

    2017-09-01

    A bench-scale photobioreactor system, termed Laboratory Environmental Algae Pond Simulator (LEAPS), was designed and constructed to simulate outdoor pond cultivation for a wide range of geographical locations and seasons. The LEAPS consists of six well-mixed glass column photobioreactors sparged with CO2-enriched air to maintain a set-point pH, illuminated from above by a programmable multicolor LED lighting (0 to 2,500 µmol/m2-sec), and submerged in a temperature controlled water-bath (-2 °C to >60 °C). Measured incident light intensities and water temperatures deviated from the respective light and temperature set-points on average only 2.3% and 0.9%, demonstrating accurate simulation of light and temperature conditions measured in outdoor ponds. In order to determine whether microalgae strains cultured in the LEAPS exhibit the same linear phase biomass productivity as in outdoor ponds, Chlorella sorokiniana and Nannochloropsis salina were cultured in the LEAPS bioreactors using light and temperature scripts measured previously in the respective outdoor pond studies. For Chlorella sorokiniana, the summer season biomass productivity in the LEAPS was 6.6% and 11.3% lower than in the respective outdoor ponds in Rimrock, Arizona, and Delhi, California; however, these differences were not statistically significant. For Nannochloropsis salina, the winter season biomass productivity in the LEAPS was statistically significantly higher (15.2%) during the 27 day experimental period than in the respective outdoor ponds in Tucson, Arizona. However, when considering only the first 14 days, the LEAPS biomass productivity was only 9.2% higher than in the outdoor ponds, a difference shown to be not statistically significant. Potential reasons for the positive or negative divergence in LEAPS performance, relative to outdoor ponds, are discussed. To demonstrate the utility of the LEAPS in predicting productivity, two other strains – Scenedesmus obliquus and Stichococcus minor

  12. Toxicity of Superparamagnetic Iron Oxide Nanoparticles on Green Alga Chlorella vulgaris

    Directory of Open Access Journals (Sweden)

    Lotfi Barhoumi

    2013-01-01

    Full Text Available Toxicity of superparamagnetic iron oxide nanoparticles (SPION was investigated on Chlorella vulgaris cells exposed during 72 hours to Fe3O4 (SPION-1, Co0.2Zn0.8Fe2O4 (SPION-2, or Co0.5Zn0.5Fe2O4 (SPION-3 to a range of concentrations from 12.5 to 400 μg mL−1. Under these treatments, toxicity impact was indicated by the deterioration of photochemical activities of photosynthesis, the induction of oxidative stress, and the inhibition of cell division rate. In comparison to SPION-2 and -3, exposure to SPION-1 caused the highest toxic effects on cellular division due to a stronger production of reactive oxygen species and deterioration of photochemical activity of Photosystem II. This study showed the potential source of toxicity for three SPION suspensions, having different chemical compositions, estimated by the change of different biomarkers. In this toxicological investigation, algal model C. vulgaris demonstrated to be a valuable bioindicator of SPION toxicity.

  13. Optimization of the biomass production of oil algae Chlorella minutissima UTEX2341.

    Science.gov (United States)

    Li, ZhaoSheng; Yuan, HongLi; Yang, JinShui; Li, BaoZhen

    2011-10-01

    High production cost is a major obstacle to the extensive use of microalgae biodiesel. To cut the cost and achieve higher biomass productivity, Chlorella minutissima UTEX2341 was cultured under photoheterotrophic conditions. With the carbon, nitrogen and phosphorus concentration of 26.37, 2.61 and 0.03 g L⁻¹ d⁻¹ respectively, a maximum biomass productivity of 1.78 g L⁻¹ d⁻¹ was obtained, which was 59 times more than that cultured under autotrophic condition. The lipid productivity reached 0.29 g L⁻¹ d⁻¹, which was 11.9 times higher than the highest value reported by Oh et al. (2010). The conversion rate of microalgae lipids to FAME was found to be elevated from 45.65% to 62.97% and the FAME productivity increased from 1.16 to 180.68 mg L⁻¹ d⁻¹ after the optimization. 94% of the fatty acid of C. minutissima UTEX2341 was found to be composed of palmitic, oleic, linoleic and γ linoleic and the unsaturated fatty acids were the main parts (79.42%).

  14. Anaerobic Digestion of Algae Biomass to Produce Energy during Wastewater Treatment.

    Science.gov (United States)

    Peng, Shanshan; Colosi, Lisa M

    2016-01-01

    Water resource recovery facilities (WRRFs) are asked to improve both energy efficiency and nutrient removal efficacy. Integration of algaculture offers several potential synergies that could address these goals, including an opportunity to leverage anaerobic digestion at WRRFs. In this study, bench-scale experiments are used to measure methane yield during co-digestion of Scenedesmus dimorphus or mixed WRRF-grown algae with WRRF biosolids. The results indicate that normalized methane yield decreases with increasing algae content in a manner than can be reasonably well fit using linear regression (R(2) = 67%). It is thus possible to predict methane yield for any mixture of algae and biosolids based on the methane yield of the biosolids alone. Using revised methane yields, the energy return on investment of a typical WRRF increases from 0.53 (without algae) to 0.66 (with algae). Thus, algae-based wastewater treatment may hold promise for improving WRRF energy efficiency without compromising effluent quality.

  15. Fed-batch cultivation of Arthrospira and Chlorella in ammonia-rich wastewater: Optimization of nutrient removal and biomass production.

    Science.gov (United States)

    Markou, Giorgos

    2015-10-01

    In the present work the cyanobacterium Arthrospira platensis and the microalga Chlorella vulgaris were fed-batch cultivated in ammonia-rich wastewater derived from the anaerobic digestion of poultry litter. Aim of the study was to maximize the biomass production along with the nutrient removal aiming to wastewater treatment. Ammonia and phosphorus removals were very high (>95%) for all cultures investigated. Both microorganisms were able to remove volatile fatty acids to an extent of >90%, indicating that they were capable of mixotrophic growth. Chemical oxygen demand and proteins were also removed in various degrees. In contrast, in all cultures carbohydrate concentration was increased. The biochemical composition of the microorganisms varied greatly and was influenced by the indicate that the nutrient availability. A. platensis accumulated carbohydrates (≈ 40%), while C. vulgaris accumulated lipids (≈ 50%), rendering them interesting for biofuel production.

  16. Domestication of the green alga Chlorella sorokiniana: reduction of antenna size improves light-use efficiency in a photobioreactor

    National Research Council Canada - National Science Library

    Cazzaniga, Stefano; Dall'Osto, Luca; Szaub, Joanna; Scibilia, Luca; Ballottari, Matteo; Purton, Saul; Bassi, Roberto

    2014-01-01

    .... Among the different microalgae, Chlorella species are of interest because of their high productivity, high lipid content, and resistance to the high light conditions typical of photobioreactors...

  17. Assessment of a tannin-based organic polymer to harvest Chlorella vulgaris biomass from swine wastewater digestate phycoremediation.

    Science.gov (United States)

    Mezzari, M P; da Silva, M L B; Pirolli, M; Perazzoli, S; Steinmetz, R L R; Nunes, E O; Soares, H M

    2014-01-01

    This study investigated the efficiency of an organic tannin polymer alone or amended with polyacrylamide to harvest Chlorella vulgaris biomass grown in a laboratory-scale photobioreactor treating swine wastewater digestate. The effect of biomass concentration, tannin (TAN) dosages and changes in pH were evaluated in jar test experiments. Among the TAN concentrations tested (11, 22, 44, 89, 178 mg L(-1)), 11 mg L(-1) showed the highest biomass recovery (97%). The highest coagulation/ flocculation efficiencies were obtained at pH 5 to 7. Flocculation efficiency improved from 50 to 97% concomitant with the increasing biomass concentrations from 45 to 165 mg L(-1), respectively. Recovery efficiencies above 95% were achieved with the same TAN dosage (11 mg L(-1)) irrespective of the concentration of organic carbon present (75 to 300 mg TOC L(-1)). Overall, the results suggest that TAN could become an interesting alternative choice of non-toxic organic polymer for harvesting Chlorella sp. from organic-rich wastewater.

  18. Mechanism of inhibitory action of the local anaesthetic trimecaine on the growth of algae (Chlorella vulgaris).

    Science.gov (United States)

    Sersen, F; Král'ová, K

    1994-08-01

    Using the model compound trimecaine, it was found that algicidal effects exhibited by the local anaesthetics of the acetanilide type were caused by two different mechanisms. The first inhibitory mechanism occurring at low concentrations of the anaesthetic is connected with the uncoupling of the photophosphorylations in algal chloroplasts and is accompanied by the enhancement of the oxygen evolving rate in algal photosynthesis. The second mechanism of inhibition of the photosynthesis in algae, taking place at higher concentrations of the anaesthetic, is connected with the damaging of the manganese containing protein on the donor side of photosystem 2 and is accompanied by a decrease of the oxygen evolving rate in algal photosynthesis.

  19. Evaluation of an oil-producing green alga Chlorella sp. C2 for biological DeNOx of industrial flue gases.

    Science.gov (United States)

    Zhang, Xin; Chen, Hui; Chen, Weixian; Qiao, Yaqin; He, Chenliu; Wang, Qiang

    2014-09-02

    NOx, a significant portion of fossil fuel flue gases, are among the most serious environmental issues in the world and must be removed in an additional costly gas treatment step. This study evaluated the growth of the green alga Chlorella sp. C2 under a nitrite-simulated NOx environment and the removal rates of actual flue gas fixed salts (FGFSs) from Sinopec's Shijiazhuang refinery along with lipid production. The results showed that nitrite levels lower than 176.5 mM had no significant adverse effects on the cell growth and photosynthesis of Chlorella sp. C2, demonstrating that this green alga could utilize nitrite and NOx as a nitrogen source. High concentrations of nitrite (88.25-176.5 mM) also resulted in the accumulation of neutral lipids. A 60% nitrite removal efficiency was obtained together with the production of 33% algae lipids when cultured with FGFS. Notably, the presence of nitrate in the FGFS medium significantly enhanced the nitrite removal capability, biomass and lipid production. Thus, this study may provide a new insight into the economically viable application of microalgae in the synergistic combination of biological DeNOx of industrial flue gases and biodiesel production.

  20. Assessment of factors affecting Agrobacterium-mediated genetic transformation of the unicellular green alga, Chlorella vulgaris.

    Science.gov (United States)

    Cha, Thye San; Yee, Willy; Aziz, Ahmad

    2012-04-01

    The successful establishment of an Agrobacterium-mediated transformation method and optimisation of six critical parameters known to influence the efficacy of Agrobacterium T-DNA transfer in the unicellular microalga Chlorella vulgaris (UMT-M1) are reported. Agrobacterium tumefaciens strain LBA4404 harbouring the binary vector pCAMBIA1304 containing the gfp:gusA fusion reporter and a hygromycin phosphotransferase (hpt) selectable marker driven by the CaMV35S promoter were used for transformation. Transformation frequency was assessed by monitoring transient β-glucuronidase (GUS) expression 2 days post-infection. It was found that co-cultivation temperature at 24°C, co-cultivation medium at pH 5.5, 3 days of co-cultivation, 150 μM acetosyringone, Agrobacterium density of 1.0 units (OD(600)) and 2 days of pre-culture were optimum variables which produced the highest number of GUS-positive cells (8.8-20.1%) when each of these parameters was optimised individually. Transformation conducted with the combination of all optimal parameters above produced 25.0% of GUS-positive cells, which was almost a threefold increase from 8.9% obtained from un-optimised parameters. Evidence of transformation was further confirmed in 30% of 30 randomly-selected hygromycin B (20 mg L(-1)) resistant colonies by polymerase chain reaction (PCR) using gfp:gusA and hpt-specific primers. The developed transformation method is expected to facilitate the genetic improvement of this commercially-important microalga.

  1. Model based analysis of transient fluorescence yield induced by actinic laser flashes in spinach leaves and cells of green alga Chlorella pyrenoidosa Chick.

    Science.gov (United States)

    Belyaeva, N E; Schmitt, F-J; Paschenko, V Z; Riznichenko, G Yu; Rubin, A B; Renger, G

    2014-04-01

    Measurements of Single Flash Induced Transient Fluorescence Yield (SFITFY) on spinach leaves and whole cells of green thermophilic alga Chlorella pyrenoidosa Chick were analyzed for electron transfer (ET) steps and coupled proton transfer (PT) on both the donor and the acceptor side of the reaction center (RC) of photosystem II (PS II). A specially developed PS II model (Belyaeva et al., 2008, 2011a) allowed the determination of ET steps that occur in a hierarchically ordered time scale from nanoseconds to several seconds. Our study demonstrates that our SFITFY data is consistent with the concept of the reduction of P680(+) by YZ in both leaves and algae (studied on spinach leaves and cells of Chlorella pyrenoidosa Chick). The multiphasic P680(+) reduction kinetics by YZ in PS II core complexes with high oxygen evolution capacity was seen in both algae and leaves. Model simulation to fit SFITFY curves for dark adapted species used here gives the rate constants to verify nanosecond kinetic stages of P680(+) reduction by YZ in the redox state S1 of the water oxidizing complex (WOC) shown in Kühn et al. (2004). Then a sequence of relaxation steps in the redox state S1, outlined by Renger (2012), occurs in both algae and leaves as a similar non-adiabatic ET reactions. Coupled PT is discussed briefly to understand a rearrangement of hydrogen bond protons in the protein matrix of the WOC (Umena et al., 2011). On the other hand, present studies showed a slower reoxidation of reduced QA by QB in algal cells as compared with that in a leaf that might be regarded as a consequence of differences of spatial domains at the QB-site in leaves compared to algae. Our comparative study helped to correlate theory with experimental data for molecular photosynthetic mechanisms in thylakoid membranes. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  2. Evaluation of zinc oxide nanoparticles toxicity on marine algae chlorella vulgaris through flow cytometric, cytotoxicity and oxidative stress analysis.

    Science.gov (United States)

    Suman, T Y; Radhika Rajasree, S R; Kirubagaran, R

    2015-03-01

    The increasing industrial use of nanomaterials during the last decades poses a potential threat to the environment and in particular to organisms living in the aquatic environment. In the present study, the toxicity of zinc oxide nanoparticles (ZnO NPs) was investigated in Marine algae Chlorella vulgaris (C. vulgaris). High zinc dissociation from ZnONPs, releasing ionic zinc in seawater, is a potential route for zinc assimilation and ZnONPs toxicity. To examine the mechanism of toxicity, C. vulgaris were treated with 50mg/L, 100mg/L, 200mg/L and 300 mg/L ZnO NPs for 24h and 72h. The detailed cytotoxicity assay showed a substantial reduction in the viability dependent on dose and exposure. Further, flow cytometry revealed the significant reduction in C. vulgaris viable cells to higher ZnO NPs. Significant reductions in LDH level were noted for ZnO NPs at 300 mg/L concentration. The activity of antioxidant enzyme superoxide dismutase (SOD) significantly increased in the C. vulgaris exposed to 200mg/L and 300 mg/L ZnO NPs. The content of non-enzymatic antioxidant glutathione (GSH) significantly decreased in the groups with a ZnO NPs concentration of higher than 100mg/L. The level of lipid peroxidation (LPO) was found to increase as the ZnO NPs dose increased. The FT-IR analyses suggested surface chemical interaction between nanoparticles and algal cells. The substantial morphological changes and cell wall damage were confirmed through microscopic analyses (FESEM and CM).

  3. Toxicity of fluorotelomer carboxylic acids to the algae Pseudokirchneriella subcapitata and Chlorella vulgaris, and the amphipod Hyalella azteca.

    Science.gov (United States)

    Mitchell, Rebecca J; Myers, Anne L; Mabury, Scott A; Solomon, Keith R; Sibley, Paul K

    2011-11-01

    Perfluorinated acids (PFAs) have elicited significant global regulatory and scientific concern due to their persistence and global pervasiveness. A source of PFAs in the environment is through degradation of fluorotelomer carboxylic acids (FTCAs) but little is known about the toxicity of these degradation products. Previous work found that FTCAs were two to three orders of magnitude more toxic to some freshwater invertebrates than their PFA counterparts and exhibited comparable chain-length-toxicity relationships. In this study, we investigated the toxicity of the 6:2, 8:2, and 10:2 saturated (FTsCA) and unsaturated (FTuCA) fluorotelomer carboxylic acids to two species of freshwater algae, Chlorella vulgaris and Pseudokirchneriella subcapitata, and the amphipod, Hyalella azteca. C. vulgaris was generally the most sensitive species, with EC₅₀s of 26.2, 31.8, 11.1, and 4.2 mg/L for the 6:2 FTsCA, 6:2 FTuCA, 8:2 FTuCA, and 10:2 FTsCA, respectively. H. azteca was most sensitive to the 8:2 FTsCA and 10:2 FTuCA, with LC₅₀s of 5.1 and 3.7 mg/L. The toxicity of the FTCAs generally increased with increasing carbon chain length, and with saturation for most of the species tested, with the exception of P. subcapitata, which did not exhibit any trend. These observations agree with chain-length-toxicity relationships previously reported for the PFCAs and support the greater toxicity of the FTCAs compared to PFCAs. However, the toxicity values are approximately 1000-fold above those detected in the environment indicating negligible risk to aquatic invertebrates.

  4. Effects of glufosinate on antioxidant enzymes, subcellular structure, and gene expression in the unicellular green alga Chlorella vulgaris

    Energy Technology Data Exchange (ETDEWEB)

    Qian Haifeng; Chen Wei; Sheng, G. Daniel; Xu Xiaoyan; Liu Weiping [College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032 (China); Fu Zhengwei [College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032 (China)], E-mail: azwfu2003@yahoo.com.cn

    2008-07-30

    Greater exposure to herbicide increases the likelihood of harmful effects in humans and the environment. Glufosinate, a non-selective herbicide, inhibits glutamine synthetase (GS) and thus blocks ammonium assimilation in plants. In the present study, the aquatic unicellular alga Chlorella vulgaris was chosen to assess the effects of acute glufosinate toxicity. We observed physiological changes during 12-96 h of exposure, and gene transcription during 6-48 h of exposure. Exposure to glufosinate increased malondialdehyde content by up to 2.73 times compared with the control, suggesting that there was some oxidative damage. Electron microscopy also showed that there were some chloroplast abnormalities in response to glufosinate. The activities of the antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) also increased markedly in the presence of glufosinate. Maximum activities of SOD, POD, and CAT were 2.90, 2.91, and 2.48 times that of the control, respectively. These elevated activities may help alleviate oxidative damage. A real-time polymerase chain reaction (PCR) assay showed changes in transcript abundances of three photosynthetic genes, psaB, psbC, and rbcL. The results showed that glufosinate reduced the transcript abundances of the three genes after 12 h exposure. The lowest abundances of psaB, psbC and rbcL transcripts in response to glufosinate exposure were 38%, 16% and 43% of those of the control, respectively. Our results demonstrate that glufosinate affects the activities of antioxidant enzymes, disrupts chloroplast ultrastructure, and reduces transcription of photosynthesis-related genes in C. vulgaris.

  5. Estudio cinético e isotermas de adsorción de Ni(II) y Zn(II) utilizando biomasa del alga Chlorella sp. inmovilizada

    OpenAIRE

    SÁNCHEZ T, EDNA LILIAN; GARZA GONZÁLEZ, MA. TERESA; ALMAGUER CANTÚ, VERÓNICA; SÁENZ TAVERA, ISABEL DEL CARMEN; LIÑÁN MONTES, ADRIANA

    2008-01-01

    En el presente estudio se determinó la capacidad de bioadsorción de níquel(II) y zinc(II) por la biomasa del alga Chlorella sp. inmovilizada en alginato de calcio. También se determinó la cinética de bioadsorción, así como la influencia de la concentración de los metales. Los resultados fueron tratados con los modelos de isotermas de adsorción. Los datos de la cinética de bioadsorción correspondieron a una reacción de segundo orden Las isotermas experimentales de ...

  6. Biotechnological potential of immobilized algae for wastewater N, P and metal removal: a review.

    Science.gov (United States)

    Mallick, Nirupama

    2002-12-01

    This presentation comprises a review on the use of immobilized algae for wastewater nitrogen, phosphorus and metal removal purposes. Details of the use of immobilized algae, the techniques of immobilization and the effects of immobilization on cell function are included. Particularly relevant in their use for heavy metal removal from wastewaters; upon enriching the biomass in metal, can be recoverd, thereby providing economic advantages. The use of immobilized microalgae in these processes is very adequate and offers significant advantages in bioreactors. The future of this area of algal cell biotechnology is considered.

  7. Polishing of Anaerobic Secondary Effluent and Symbiotic Bioremediation of Raw Municipal Wastewater by Chlorella Vulgaris

    KAUST Repository

    Cheng, Tuoyuan

    2016-05-01

    To assess polishing of anaerobic secondary effluent and symbiotic bioremediation of primary effluent by microalgae, bench scale bubbling column reactors were operated in batch modes to test nutrients removal capacity and associated factors. Chemical oxygen demand (COD) together with oil and grease in terms of hexane extractable material (HEM) in the reactors were measured after batch cultivation tests of Chlorella Vulgaris, indicating the releasing algal metabolites were oleaginous (dissolved HEM up to 8.470 mg/L) and might hazard effluent quality. Ultrafiltration adopted as solid-liquid separation step was studied via critical flux and liquid chromatography-organic carbon detection (LC-OCD) analysis. Although nutrients removal was dominated by algal assimilation, nitrogen removal (99.6% maximum) was affected by generation time (2.49 days minimum) instead of specific nitrogen removal rate (sN, 20.72% maximum), while phosphorus removal (49.83% maximum) was related to both generation time and specific phosphorus removal rate (sP, 1.50% maximum). COD increase was affected by cell concentration (370.90 mg/L maximum), specific COD change rate (sCOD, 0.87 maximum) and shading effect. sCOD results implied algal metabolic pathway shift under nutrients stress, generally from lipid accumulation to starch accumulation when phosphorus lower than 5 mg/L, while HEM for batches with initial nitrogen of 10 mg/L implied this threshold around 8 mg/L. HEM and COD results implied algal metabolic pathway shift under nutrients stress. Anaerobic membrane bioreactor effluent polishing showed similar results to synthetic anaerobic secondary effluent with slight inhibition while 4 symbiotic bioremediation of raw municipal wastewater with microalgae and activated sludge showed competition for ammonium together with precipitation or microalgal luxury uptake of phosphorus. Critical flux was governed by algal cell concentration for ultrafiltration membrane with pore size of 30 nm, while

  8. Phycoremediation of Wastewater: Heavy Metal and Nutrient Removal Processes

    Directory of Open Access Journals (Sweden)

    Kwarciak-Kozłowska Anna

    2014-12-01

    Full Text Available Phycoremediation is the use of algae for the removal or biotrans-formation of pollutants from wastewater. The study is a novel at-tempt to integrate nutrient (N and P removal and some heavy met-als (iron, manganese and zinc bioaccumulation from municipal wastewater using two microalgae species: Chlorella vulgaris and Scenedesmus armatus. The Chlorella vulgaris showed higher re-moval of total nitrogen (TN both in influent and effluent waste water than Scenedesmus armatus. Nevertheless, more than 51% of total phosphorus (TP in effluent and 36% in influent wastewaters were removed by Scenedesmus armatus. More efficient microalga in heavy metal removal in influent wastewater was Scenedesmus armatus. The results showed that Chlorella vulgaris was appropriate for TN removal and bioaccumulation of heavy metals from effluent wastewater. Nevertheless, Scenedesmus armatus was highly pref-erable for heavy metals removal from influent wastewater.

  9. Purifying Synthetic High-Strength Wastewater by Microalgae Chlorella Vulgaris Under Various Light Emitting Diode Wavelengths and Intensities

    Directory of Open Access Journals (Sweden)

    Zhigang Ge

    2013-06-01

    Full Text Available The high-strength wastewater is now well known as a threat to the natural water since it is highly possible to arouse water eutrophication or algal blooms. The effects of various light emitting diode wavelengths and intensities on the microalgae biological wastewater treatment system was studied in this research. The various nutrient removals and economic efficiencies represented similar variation trends, and these variations under both high C and N loading treatments were similar too. The order for microalgae C. vulgaris reproduction in terms of dry weight and nutrient removal efficiency both were red > white > yellow > blue, under high carbon and nitrogen loading treatments, indicating that the red light was the optimum light wavelength. Furthermore, considering the optimal light intensity in terms of nutrient removal efficiency was 2500 and 2000 μmol/m2•s, while in terms of economic efficiency was 1000, 1500 and 2000 μmol/m2•s. Therefore, the optimum light intensity was found to be 2000 μmol/m2•s. In addition, the optimal experimental illumination time was determined as 120 h. The Chlorella vulgaris microalgae biological wastewater treatment system utilized in this research was able to purify the high-strength carbon and nitrogen wastewater effectively under optimum light wavelength and intensity.

  10. Effect of different organic matters on flocculation of Chlorella sorokiniana and optimization of flocculation conditions in swine manure wastewater.

    Science.gov (United States)

    Zhang, Bo; Chen, Sanfeng

    2015-09-01

    In this study, flocculation of Chlorella sorokiniana cultivated in swine manure wastewater, BG-11 medium and BG-11 medium supplemented with different organic matters (glucose, urea and tryptone) was investigated. The results demonstrated that the minimum amount of Al(3+) required for complete flocculation in wastewater would increase substantially, and flocculation efficiency became highly sensitive to pH. Tryptone could cause similar extent of inhibition on flocculation as in wastewater. Meanwhile, glucose could increase concentrations of Algogenic Organic Matter (AOM), inhibiting flocculation strongly at higher pH, including flocculation induced by Al(3+) and autoflocculation. However, urea had little effect on flocculation of C. sorokiniana. Moreover, the major factors: dilution times, pH and flocculants dosage, which had significant impact on flocculation efficiency of C. sorokiniana in piggery wastewater, were optimized using response surface methodology (RSM). The optimal flocculation efficiency (100%) was achieved at pH 8.5, 7-folds of dilution and 52.14 mg L(-1) of Al(3+).

  11. Determination of Algae and Macrophyte Species Distribution in Three Wastewater Stabilization Ponds Using Metagenomics Analysis

    Directory of Open Access Journals (Sweden)

    Jack Wallace

    2015-06-01

    Full Text Available This study involved the evaluation of algae and macrophyte species distributions in three wastewater stabilization ponds (WSPs at a wastewater treatment plant in Ontario, Canada, which has experienced high pH levels at the final effluent and excessive algae growth during the summer since 2003. From samples collected from the system, the relative abundances of specific algae and aquatic plant (macrophyte taxa were assessed and correlated to water chemistry data. A strong shift from the dominance of green algae, chlorophyceae, in WSP#2, to the dominance of aquatic macrophytes, embryophyta, in WSP#4, was observed and corresponded to field observations. Correlation of the abundances to nutrient parameters suggested that the macronutrient rich conditions in WSP#2 allowed floating green algae to proliferate against macrophytes. In WSP#1 and WSP#4, macrophytes competed against algae and thrived, due to their adaptability to lower nutrient conditions. The pH increases occurred primarily in WSP#2 and were not buffered or reduced in WSP#1 and WSP#4. Two alternatives strategies for pH control were recommended for the system: decreasing algae growth in WSP#2 through duckweed seeding or macronutrient loading reduction; or designing and implementing a constructed wetland (CW in WSP#4 with soil and vegetation to buffer pH prior to release.

  12. Conversion of membrane lipid acyl groups to triacylglycerol and formation of lipid bodies upon nitrogen starvation in biofuel green algae Chlorella UTEX29.

    Science.gov (United States)

    Goncalves, Elton C; Johnson, Jodie V; Rathinasabapathi, Bala

    2013-11-01

    Algal lipids are ideal biofuel sources. Our objective was to determine the contributors to triacylglycerol (TAG) accumulation and lipid body formation in Chlorella UTEX29 under nitrogen (N) deprivation. A fivefold increase in intracellular lipids following N starvation for 24 h confirmed the oleaginous characteristics of UTEX29. Ultrastructural studies revealed increased number of lipid bodies and decreased starch granules in N-starved cells compared to N-replete cells. Lipid bodies were observed as early as 3 h after N removal and plastids collapsed after 48 h of stress. Moreover, the identification of intracellular pyrenoids and differences in the expected nutritional requirements for Chlorella protothecoides (as UTEX29 is currently classified) led us to conduct a phylogenetic study using 18S and actin cDNA sequences. This indicated UTEX29 to be more phylogenetically related to Chlorella vulgaris. To investigate the fate of different lipids after N starvation, radiolabeling using ¹⁴C-acetate was used. A significant decrease in ¹⁴C-galactolipids and phospholipids matched the increase in ¹⁴C-TAG starting at 3 h of N starvation, consistent with acyl groups from structural lipids as sources for TAG under N starvation. These results have important implications for the identification of key steps controlling oil accumulation in N-starved biofuel algae and demonstrate membrane recycling during lipid body formation.

  13. Reduction in toxicity of wastewater from three wastewater treatment plants to alga (Scenedesmus obliquus) in northeast China.

    Science.gov (United States)

    Zhang, Ying; Sun, Qing; Zhou, Jiti; Masunaga, Shigeki; Ma, Fang

    2015-09-01

    The toxicity of municipal wastewater to the receiving water bodies is still unknown, due to the lack of regulated toxicity based index for wastewater discharge in China. Our study aims at gaining insight into the acute toxic effects of local municipal wastewater on alga, Scenedesmus obliquus. Four endpoints, i.e. cell density, chlorophyll-A concentration, superoxide dismutase (SOD) activity and cell membrane integrity, of alga were analyzed to characterize the acute toxicity effects of wastewater from municipal wastewater treatment plants (WWTPs) with different treatment techniques: sequencing batch reactor (SBR), Linpor and conventional activated sludge. Influent and effluent from each treatment stage in these three WWTPs were sampled and evaluated for their acute toxicity. Our results showed that all three techniques can completely affect the algal chlorophyll-A synthesis stimulation effects of influent; the algal cell growth stimulation effect was only completely removed by the secondary treatment process in conventional activated sludge technique; toxic effects on cell membrane integrity of two influents from WWTPs with SBR and conventional activated sludge techniques were completely removed; the acute toxicity on SOD activity was partially reduced in SBR and conventional activated sludge techniques while not significantly reduced by Linpor system. As to the disinfection unit, NaClO disinfection enhanced wastewater toxicity dramatically while UV radiation had no remarkable influence on wastewater toxicity. Our results illustrated that SOD activity and chlorophyll-A synthesis were relatively sensitive to municipal wastewater toxicity. Our results would aid to understand the acute toxicity of municipal wastewater, as well as the toxicity removal by currently utilized treatment techniques in China.

  14. An In-Vitro Investigation of the Antibacterial Effects of the Methanol and Aqueous Extracts and the Supernatant of the Algae Chlorella vulgaris CCATM 210-1 on Multiantibiotic-Resistant Staphylococcus aureus Isolates Causing Urinary Tract Infections

    Directory of Open Access Journals (Sweden)

    Senobar Asadi

    2016-04-01

    Full Text Available Algae contain compounds, some of which have antibacterial properties. For example, the antibiotic Chlorellin can be mentioned, which is extracted from Chlorella species. The methanol and aqueous extracts, and the supernatant of the algae Chlorella vulgaris CCATM- 210-1 were used in this study. After culturing the Algae and preparing the supernatant and extracts, the antibacterial effects of the extracts and supernatant of this algae against multidrugresistant (MDR Staphylococcus aureus isolates causing urinary tract infections were determined using the microdilution and checkerboard titration methods. In the microdilution method, first, the aqueous extract of this algae at a concentration of 0.72 ± 0.22 mg/ml could inhibit the growth of the bacteria being tested. Then, the methanol extract and the supernatant of this algae at concentrations of 0.98 ± 0.68 and 1 ± 0.26 mg/ml, respectively, inhibited the growth of the bacteria being studied. The sum of the FIC of the methanol and aqueous extracts of the algae Chlorella vulgaris CCATM 210-1 in this study, showed the indifference of these two extracts towards each other.

  15. The removal efficiency of nitrogen and phosphorus wastes and multiplication in biomass in green alga Chlorella vulgaris%小球藻脱氮除磷及其生物量增殖潜力的研究

    Institute of Scientific and Technical Information of China (English)

    杨福利; 李秀辰; 白晓磊; 金星; 曲孟

    2014-01-01

    The removal efficiency of nitrogen and phosphorus wastes and multiplication in biomass in green alga Chlorella vulgaris were studied at various nitrogen and phosphorus concentrations. The results showed that NH+4-N and PO3-4 -P were removed effectively by the green alga for 72 h cultivation, the removal efficiency of above 90% at concentration of 2. 0-6. 0 mg/L for NH+4-N, the removal efficiency of 94. 6% at concentration of 0. 590 mg/L for PO3-4 -P, and with the maximum value of 2. 657 mg/(L·d) in NH+4-N and 0. 445 mg/(L·d) in PO3-4 -P. Also, the alga had increase from 1. 33í107 cells/mL to 2. 61í107 cells/mL in cell density when the concentration of NH+4-N was increased from 0. 8 to 10. 0 mg/L in 72 h cultivation. In the culture medium, the pH value in the wastewater was changed from 8. 19 to 9. 74 during 72 hours cultivation, indicating that cultivation of Chlorella vul-garis in wastewater would have great potential in water purification and algal production.%在实验室条件下模拟养殖污水进行海水小球藻Chlorella vulgaris栽培试验,探索小球藻对污水中氮、磷的去除效果及其生物量增殖的情况。结果表明:小球藻能有效去除污水中的NH+4-N和PO3-4-P;当NH+4-N浓度为2.0~6.0 mg/L时,去除率在90%以上, PO3-4-P浓度为0.590 mg/L时,去除率达94.6%;小球藻对NH+4-N和PO3-4-P的去除速率最大分别可达到2.657、0.445 mg/( L· d);当污水中NH+4-N浓度由0.8 mg/L升至10.0 mg/L时,培养72 h后小球藻细胞密度由1.33×107 cells/mL增至2.61×107 cells/mL;栽培期间,污水的pH 为8.19~9.74,适合于小球藻生长。研究表明,利用养殖污水栽培小球藻,不仅可以有效地净化污水,还可以获得较大的藻细胞生物量。

  16. Simultaneous microalgal biomass production and CO2 fixation by cultivating Chlorella sp. GD with aquaculture wastewater and boiler flue gas.

    Science.gov (United States)

    Kuo, Chiu-Mei; Jian, Jhong-Fu; Lin, Tsung-Hsien; Chang, Yu-Bin; Wan, Xin-Hua; Lai, Jinn-Tsyy; Chang, Jo-Shu; Lin, Chih-Sheng

    2016-12-01

    A microalgal strain, Chlorella sp. GD, cultivated in aquaculture wastewater (AW) aerated with boiler flue gas, was investigated. When AW from a grouper fish farm was supplemented with additional nutrients, the microalgal biomass productivity after 7days of culture was 0.794gL(-1)d(-1). CO2 fixation efficiencies of the microalgal strains aerated with 0.05, 0.1, 0.2, and 0.3vvm of boiler flue gas (containing approximately 8% CO2) were 53, 51, 38, and 30%, respectively. When the microalgal strain was cultured with boiler flue gas in nutrient-added AW, biomass productivity increased to 0.892gL(-1)d(-1). In semi-continuous cultures, average biomass productivities of the microalgal strain in 2-day, 3-day, and 4-day replacement cultures were 1.296, 0.985, and 0.944gL(-1)d(-1), respectively. These results demonstrate the potential of using Chlorella sp. GD cultivations in AW aerated with boiler flue gas for reusing water resources, reducing CO2 emission, and producing microalgal biomass.

  17. Effect of nitrogen and phosphorus concentration on their removal kinetic in treated urban wastewater by Chlorella vulgaris.

    Science.gov (United States)

    Ruiz, J; Alvarez, P; Arbib, Z; Garrido, C; Barragán, J; Perales, J A

    2011-10-01

    This study evaluates the feasibility of removing nutrients by the microalgae Chlorella vulgaris, using urban wastewater as culture medium, namely the effluent subjected to secondary biological treatment in a wastewater treatment plant (WWTP). For this, laboratory experiments were performed in batch cultures to study the effect of initial nitrogen and phosphorus concentrations on growth and reduction of nutrient performance of C. vulgaris. The microalga was cultivated in enriched wastewater containing different phosphorus (1.3-143.5 mg x L(-1) P.PO4(3-)), ammonium (5.8-226.8 mg x L(-1) N-NH4+) and nitrate (1.5-198.3 mg x L(-1) N-NO3-) concentrations. The nutrient removal and growth kinetics have been studied: maximum productivity of 0.95 g SS x L(-1) x day(-1), minimum yield factor for cells on substrate (Y) of 11.51 g cells x g nitrogen(-1) and 0.04 g cells x g phosphorus(-1) were observed. The results suggested that C. vulgaris has a high potential to reduce nutrients in secondary WWTP effluents.

  18. Teor de clorofila e perfil de sais minerais de Chlorella vulgaris cultivada em solução hidropônica residual Chlorophyll content and minerals profile in the microalgae Chlorella vulgaris cultivated in hydroponic wastewater

    Directory of Open Access Journals (Sweden)

    Fabiano Cleber Bertoldi

    2008-02-01

    Full Text Available O cultivo de microalgas representa uma potencial fonte de biomassa rica em clorofila e sais minerais como: fósforo, ferro, manganês, cobre, zinco, magnésio e cálcio. Este experimento teve como objetivo avaliar a composição de minerais, bem como determinar o teor de clorofila a e b da microalga Chlorella vulgaris cultivada em solução hidropônica residual em três diferentes concentrações comparadas com um cultivo controle. Os resultados mostraram que os teores de clorofila a e b da microalga não apresentaram diferença significativa entre os cultivos. Com relação à composição dos sais minerais, a Chlorella cultivada na solução residual mais concentrada apresentou valores superiores quando comparada com a cultivada nos demais cultivos. Dessa forma, a biomassa da Chlorella vulgaris demonstrou ser uma potencial fonte de clorofila e de sais minerais, quando cultivada em solução hidropônica residual, possibilitando a utilização desse resíduo de forma sustentável.The microalgaes cultive represents a potential source of biomass rich in chlorophyll and minerals as: P, Fe, Mn, Cu, Zn, Mg and Ca. This research was aimed at evaluating the composition of minerals, as well as, determining the content of chlorophyll a and b from the microalgae Chlorella vulgaris cultivated in hydroponic wastewater in three different concentrations compared with the control cultive. The results showed that the contents of chlorophyll a and b of the microalgae did not show significant difference between the cultives. In relation to the composition of the minerals, the Chlorella cultivated in the most concentrated wastewater, showed higher values when compared with the one cultivated in the others cultures. In this manner, the Chlorella vulgaris biomass demonstrated to be a potential source of chlorophyll and minerals, when cultivated in hydroponic wastewater, allowing the use of this residue in a sustainable way.

  19. TREATMENT OF WASTEWATER FROM AMINO ACID FACTORY BY CHLORELLA VULGARIS C9-JN2010%利用普通小球藻Chlorella vulgaris C9-JN2010处理氨基酸工业废水的研究

    Institute of Scientific and Technical Information of China (English)

    李宇佶; 李昌灵; 徐国华; 王武; 杨海麟

    2012-01-01

    This research was to treat amino acid wastewater by chlorella vulgaris C9-JN2010 and to achieve the use of waste water harmless. Therefore, feasibility of microalgae culture of chlorella vulgaris was studied the in bubbled column photo-bioreactor with different content amino acid wastewater medium, which the photo-bioreactor was illuminated at 4 000 lux (Light-dark cycle is l6h:8h) and air flow was 0.lvvm. The algae inoculums were cultivated at (25±1)℃ and pH(6.5±0.5). Results were as follows: different content amino acid wastewaters had significant effects on chlorella vulgaris, at optimum 40% wastewater medium, which its biomass yield, special growth rate and production intensity were 0.731 g/L, 0.565 d-1 and 0.243 g/ (L.d) respectively; there were hardly total nitrogen and phosphorus residues in culture medium after three or four days cultunng, which removal of total nitrogen, phosphorus and COD were 92.0%, 98.0% and 80.0% and their removal intensities were 30.7,3.28 and 133.3 mg/(L.d) respectively. Therefore, nutrition of N, P and COD form amino acid wastewater was thoroughly removed to treat wastewater successfully.%用普通小球藻Chlorella vulgaris C9-JN2010处理氨基酸工业废水,实现废水无害化利用.在微型鼓泡式光反应器中,(25±1)℃,pH(6.5±0.5),0.1 vvm空气流速,4 000 lux,16h∶8h光暗比条件下,分别考察小球藻在体积分数为20%、40%、60%、80%及100%的氨基酸废水中培养生物量变化及TN、TP、COD的去除率.结果表明,体积分数40%氨基酸废水处理效果最好,停留时间3~4 d,藻细胞干重、比生长速率和最大生产强度分别为0.731g/L、0.565 d-1、0.243g /(L·d);废水中TN、TP及COD的去除率分别为92.0%、98.0%及80.0%,对应去除强度分别为30.7、3.28、133.3mg/(L·d).利用小球藻可以较彻底的去除氨基酸废水中氮、磷及COD等营养,达到污水处理效果.

  20. Wastewater use in algae production for generation of renewable resources: a review and preliminary results.

    Science.gov (United States)

    Dalrymple, Omatoyo K; Halfhide, Trina; Udom, Innocent; Gilles, Benjamin; Wolan, John; Zhang, Qiong; Ergas, Sarina

    2013-01-05

    Microalgae feedstock production can be integrated with wastewater and industrial sources of carbon dioxide. This study reviews the literature on algae grown on wastewater and includes a preliminary analysis of algal production based on anaerobic digestion sludge centrate from the Howard F. Curren Advanced Wastewater Treatment Plant (HFC AWTP) in Tampa, Florida and secondary effluent from the City of Lakeland wastewater treatment facilities in Lakeland, Florida. It was demonstrated that a mixed culture of wild algae species could successfully be grown on wastewater nutrients and potentially scaled to commercial production. Algae have demonstrated the ability to naturally colonize low-nutrient effluent water in a wetland treatment system utilized by the City of Lakeland. The results from these experiments show that the algae grown in high strength wastewater from the HFC AWTP are light-limited when cultivated indoor since more than 50% of the outdoor illumination is attenuated in the greenhouse.An analysis was performed to determine the mass of algae that can be supported by the wastewater nutrients (mainly nitrogen and phosphorous) available from the two Florida cities. The study was guided by the growth and productivity data obtained for algal growth in the photobioreactors in operation at the University of South Florida. In the analysis, nutrients and light are assumed to be limited, while CO2 is abundantly available. There is some limitation on land, especially since the HFC AWTP is located at the Port of Tampa. The temperature range in Tampa is assumed to be suitable for algal growth year round. Assuming that the numerous technical challenges to achieving commercial-scale algal production can be met, the results presented suggest that an excess of 71 metric tons per hectare per year of algal biomass can be produced. Two energy production options were considered; liquid biofuels from feedstock with high lipid content, and biogas generation from anaerobic

  1. Wastewater use in algae production for generation of renewable resources: a review and preliminary results

    Science.gov (United States)

    2013-01-01

    Microalgae feedstock production can be integrated with wastewater and industrial sources of carbon dioxide. This study reviews the literature on algae grown on wastewater and includes a preliminary analysis of algal production based on anaerobic digestion sludge centrate from the Howard F. Curren Advanced Wastewater Treatment Plant (HFC AWTP) in Tampa, Florida and secondary effluent from the City of Lakeland wastewater treatment facilities in Lakeland, Florida. It was demonstrated that a mixed culture of wild algae species could successfully be grown on wastewater nutrients and potentially scaled to commercial production. Algae have demonstrated the ability to naturally colonize low-nutrient effluent water in a wetland treatment system utilized by the City of Lakeland. The results from these experiments show that the algae grown in high strength wastewater from the HFC AWTP are light-limited when cultivated indoor since more than 50% of the outdoor illumination is attenuated in the greenhouse. An analysis was performed to determine the mass of algae that can be supported by the wastewater nutrients (mainly nitrogen and phosphorous) available from the two Florida cities. The study was guided by the growth and productivity data obtained for algal growth in the photobioreactors in operation at the University of South Florida. In the analysis, nutrients and light are assumed to be limited, while CO2 is abundantly available. There is some limitation on land, especially since the HFC AWTP is located at the Port of Tampa. The temperature range in Tampa is assumed to be suitable for algal growth year round. Assuming that the numerous technical challenges to achieving commercial-scale algal production can be met, the results presented suggest that an excess of 71 metric tons per hectare per year of algal biomass can be produced. Two energy production options were considered; liquid biofuels from feedstock with high lipid content, and biogas generation from anaerobic

  2. Use of algae for removing heavy metal ions from wastewater: progress and prospects.

    Science.gov (United States)

    Mehta, S K; Gaur, J P

    2005-01-01

    Many algae have immense capability to sorb metals, and there is considerable potential for using them to treat wastewaters. Metal sorption involves binding on the cell surface and to intracellular ligands. The adsorbed metal is several times greater than intracellular metal. Carboxyl group is most important for metal binding. Concentration of metal and biomass in solution, pH, temperature, cations, anions and metabolic stage of the organism affect metal sorption. Algae can effectively remove metals from multi-metal solutions. Dead cells sorb more metal than live cells. Various pretreatments enhance metal sorption capacity of algae. CaCl2 pretreatment is the most suitable and economic method for activation of algal biomass. Algal periphyton has great potential for removing metals from wastewaters. An immobilized or granulated biomass-filled column can be used for several sorption/desorption cycles with unaltered or slightly decreased metal removal. Langmuir and Freundlich models, commonly used for fitting sorption data, cannot precisely describe metal sorption since they ignore the effect of pH, biomass concentration, etc. For commercial application of algal technology for metal removal from wastewaters, emphasis should be given to: (i) selection of strains with high metal sorption capacity, (ii) adequate understanding of sorption mechanisms, (iii) development of low-cost methods for cell immobilization, (iv) development of better models for predicting metal sorption, (v) genetic manipulation of algae for increased number of surface groups or over expression of metal binding proteins, and (vi) economic feasibility.

  3. Identification and evaluation of a dominant alga from municipal wastewater in removal of nutrients.

    Science.gov (United States)

    Yang, Yixuan; Tang, Fei; Su, Xiaoling; Yin, Hua; Ge, Fei

    2016-12-01

    To access better removal of nutrients with algae-based techniques, a dominant alga from real municipal wastewater was identified and its capacity in removing low concentrations of nitrogen (NH(+)4 or NO(-)3) and phosphorus (PO(3-)4) was evaluated. Results showed that Oedogonium brevicingulatum, a filamentous green alga, was confirmed as the dominant alga in the secondary effluent of a municipal wastewater treatment plant by polymerase chain reaction-denaturing gradient gel electrophoresis. Low concentrations of NH(+)4 or NO(-)3 (≤5 mg N L(-1)) and PO(3-)4 (≤0.5 mg P L(-1)) were 100% removed by the algae in a 7-d test. The maximum nutrient removal rate (Vmax) and the half-saturation constant (Km) for NH(+)4 (10.03 ± 0.95 mg g(-1)d(-1) and 0.19 ± 0.03 mg L(-1)) and NO(-)3 (8.43 ± 0.21 mg g(-1) d(-1) and 0.27 ± 0.11 mg L(-1)) indicated the uptake capability for NH(+)4 is higher than that for NO(-)3. Meanwhile, it showed higher affinity for PO(3-)4 (Vmax: 1.42 ± 0.02 mg g(-1) d(-1); Km: 0.02 ± 0.00 mg L(-1)) with NH(+)4 as nitrogen source than that (Vmax: 1.24 ± 0.15 mg g(-1) d(-1); Km: 0.06 ± 0.03 mg L(-1)) with NO(-)3 as nitrogen source. Moreover, nutrient removal efficiencies were observed steady when nitrogen/phosphorus ratio ranged from 5:1 to 20:1. These results suggest that the dominant algae from municipal wastewater have potentials to be applied in nutrient removal.

  4. An In-Vitro Investigation of the Antibacterial Effects of the Acetone and Ethanol Extracts and the Supernatant of the Algae Chlorella vulgaris CCATM- 210-1 on Some of the Gram-Negative Bacterial Foodborne Pathogens

    Directory of Open Access Journals (Sweden)

    Yasaman Asadi

    2016-09-01

    Full Text Available Algae are rich sources of amino acids, terpenoids, florentines, alkanes, halogenated ketones, steroidal compounds, fatty acids, and phenols that can be used in the pharmaceutical industry. The acetone and ethanol extracts, and the supernatant of the algae Chlorella vulgaris CCATM- 210-1, were used in this study. After culturing the Algae, and preparing the supernatant and extracts, the antibacterial effects of the extracts and supernatant of this algae against some of the gram-negative bacterial foodborne pathogens were determined using the well plate and agar disk diffusion methods. According to the study conducted, the acetone and ethanol extracts and the supernatant of the algae Chlorella vulgaris CCATM- 210-1 showed acceptable antibacterial properties against some of the bacteria being studied, at concentrations of 1.25, 2.5, 5, and 10 mg/ml in the well plate and agar disk diffusion methods. The maximum inhibition zone diameters in the well plate and agar disk diffusion methods, were 36.8 and 35.4 mm, respectively, which were related to the bacterium Proteus mirabilis PTCC 1776 and were observed at a 10 mg/ml concentration of the acetone extract. By comparing the mean inhibition zone diameters among the acetone and ethanol extracts and a mixture of the two extracts using the well plate method, it can be concluded that the acetone and ethanol extracts of Chlorella vulgaris CCATM- 210-1 are indifferent to each other. This analysis was also true of the agar disk diffusion method.

  5. Algae Removal by Electro-coagulation Process, Application for Treatment of the Effluent from an Industrial Wastewater Treatment Plant

    National Research Council Canada - National Science Library

    GH Azarian; AR Mesdaghinia; F Vaezi; R Nabizadeh; D Nematollahi

    2007-01-01

    .... In this study, an electro-coagulation reactor was examined to re­move algae from the final effluent of the wastewater treatment plant belong to Bu-Ali Industrial Estates (Hamadan City).  Methods...

  6. Water-Nutrient-food Nexus The Role of Green Algae for Sustainable Food Production in Urban Wetlands Through Untreated Wastewater

    OpenAIRE

    Hussnain Mukhtar; Muhammad Imran

    2016-01-01

    The nutrients in domestic wastewater are increasingly being regarded as a valuable resource for energy and nutrient recovery for an Eco-city. The nutrient stream can be used safely for food production through ecological engineering interventions (introduction of green algae in urban wetlands). Effects of wastewater on growth yield and microbial contamination on hydroponic tomato (Lycopersicon esculentum) was studied in pilot scale wetland for 6 month under the presence of green algae (Euglena...

  7. Isolation of a bacterial strain, Acinetobacter sp. from centrate wastewater and study of its cooperation with algae in nutrients removal.

    Science.gov (United States)

    Liu, Hui; Lu, Qian; Wang, Qin; Liu, Wen; Wei, Qian; Ren, Hongyan; Ming, Caibing; Min, Min; Chen, Paul; Ruan, Roger

    2017-07-01

    Algae were able to grow healthy on bacteria-containing centrate wastewater in a pilot-scale bioreactor. The batch experiment indicated that the co-cultivation of algae and wastewater-borne bacteria improved the removal efficiencies of chemical oxygen demand and total phosphorus in centrate wastewater to 93.01% and 98.78%, respectively. A strain of beneficial aerobic bacteria, Acinetobacter sp., was isolated and its biochemical characteristics were explored. Synergistic cooperation was observed in the growth of algae and Acinetobacter sp. Removal efficiencies of some nutrients were improved significantly by the co-cultivation of algae and Acinetobacter sp. After treatment, residual nutrients in centrate wastewater reached the permissible discharge limit. The cooperation between algae and Acinetobacter sp. was in part attributed to the exchange of carbon dioxide and oxygen between the algae and bacteria. This synergetic relationship between algae and Acinetobacter sp. provided a promising way to treat the wastewater by improving the nutrients removal and biomass production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Investigating the impact of NaCl salinity on growth, β-carotene, and chlorophyll a in the content life of halophytes of algae Chlorella sp.

    Directory of Open Access Journals (Sweden)

    Mojtaba Fathi

    2013-05-01

    Full Text Available Algae are used for many purposes as: food industry, animal feeding, soil enrichment andbiodiesel production. Chlorella is widely cultivated from microalgae species as it is rich in nutrients andhas its implementation as a healthy food use. In this study, the impact of NaCl salinity on growth, betacarotene,and chlorophyll a of Chlorella sp. has been investigated. This study results in three salinities(10, 30, 50 g L-1, respectively have shown that 30 g L-1 concentration has the highest value of cellnumber in day 15th and there was no significant difference between salinities on day 15th (p>0.05. Βetacaroteneresult has shown 50 g L-1 salinity and the highest value of beta-carotene did not indicate anystatistically significant differences between treatments (p>0.05. Chlorophyll a result has shown highestvalue in all treatments (it was in 50 g L-1. However, there was no significant difference betweensalinities on day 5th (p>0.05.

  9. Effective Biological DeNOx of Industrial Flue Gas by the Mixotrophic Cultivation of an Oil-Producing Green Alga Chlorella sp. C2.

    Science.gov (United States)

    Chen, Weixian; Zhang, Shanshan; Rong, Junfeng; Li, Xiang; Chen, Hui; He, Chenliu; Wang, Qiang

    2016-02-01

    Nitrogen oxides (NOx) are the components of fossil flue gas that result in the most serious environmental concerns. We previously showed that the biological removal of NOx by microalgae appears superior to traditional treatments. This study optimizes the strategy for the microalgal-based DeNOx of flue gas by fed-batch mixotrophic cultivation. By using actual flue gas fixed salts (FGFS) as the nitrogen supply, the mixotrophical cultivation of the green alga Chlorella sp. C2 with high NOx absorption efficiency was optimized in a stepwise manner in a 5 L bioreactor and resulted in a maximum biomass productivity of 9.87 g L(-1) d(-1). The optimized strategy was further scaled up to 50 L, and a biomass productivity of 7.93 g L(-1) d(-1) was achieved, with an overall DeNOx efficiency of 96%, along with an average nitrogen CR of 0.45 g L(-1) d(-1) and lipid productivity of 1.83 g L(-1) d(-1). With an optimized mixotrophical cultivation, this study further proved the feasibility of using Chlorella for the combination of efficient biological DeNOx of flue gas and microalgae-based products production. Thus, this study shows a promising industrial strategy for flue gas biotreatment in plants with limited land area.

  10. Evaluation of growth and survival rate of Artemia parthenogenetica feed with micro algae (Isochrysis galbana and Chlorella vulgaris and bakery yeast (Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Mehdi Dehghan

    2011-10-01

    Full Text Available This study was done to evaluate growth and survival rate of Maharloo lake artemia (ArtemiaParthenogenetica (Bowen & Sterling, 1978 which feed with two species of microalgae (IsochrysisGalbana and Chlorella vulgaris and bakery yeast (Saccharomyces cerevisiae with different nutritiousingredients for 15 days. We evaluated them in 3rd, 7th, 11th and 15thdays of cultivation period for 4 times. This experiment was done in completely randomized design with 4 treatments (3 treatments and 1 control and each treatment has 3 replicates. Artemia parthenogenetica nauplii were feed with three different types of food that includes Isochrysis galbana microalgae (T1, Chlorella vulgaris (T2 and Saccharomyces cerevisiae yeast (T4. Control had feed with blend of these three matters. After 15 days the highest survival rate was observed in control (84.00 and the lowest one was related to the T4 (59.58 which feed with Saccharomyces cerevisiae yeast (p<0.05. The highest growth rate was observed in T4, T3, followed by T1 and T2 respectively. Achievement results showed significantdifferences between control and other treatments (p<0.05. This study proved that treatments whichfeed with blend of two micro algae's species and bakery yeast have higher survival ability than theother treatments.

  11. Use of Copper to Selectively Inhibit Brachionus calyciflorus (Predator) Growth in Chlorella kessleri (Prey) Mass Cultures for Algae Biodiesel Production.

    Science.gov (United States)

    Pradeep, Vishnupriya; Van Ginkel, Steven W; Park, Sichoon; Igou, Thomas; Yi, Christine; Fu, Hao; Johnston, Rachel; Snell, Terry; Chen, Yongsheng

    2015-08-31

    A single Brachionus rotifer can consume thousands of algae cells per hour causing an algae pond to crash within days of infection. Thus, there is a great need to reduce rotifers in order for algal biofuel production to become reality. Copper can selectively inhibit rotifers in algae ponds, thereby protecting the algae crop. Differential toxicity tests were conducted to compare the copper sensitivity of a model rotifer-B. calyciflorus and an alga, C. kessleri. The rotifer LC50 was alga was not affected up to 5 ppm Cu(II). The low pH of the rotifer stomach may make it more sensitive to copper. However, when these cultures were combined, a copper concentration of 1.5 ppm was needed to inhibit the rotifer as the alga bound the copper, decreasing its bioavailability. Copper (X ppm) had no effect on downstream fatty acid methyl ester extraction.

  12. Use of Copper to Selectively Inhibit Brachionus calyciflorus (Predator Growth in Chlorella kessleri (Prey Mass Cultures for Algae Biodiesel Production

    Directory of Open Access Journals (Sweden)

    Vishnupriya Pradeep

    2015-08-01

    Full Text Available A single Brachionus rotifer can consume thousands of algae cells per hour causing an algae pond to crash within days of infection. Thus, there is a great need to reduce rotifers in order for algal biofuel production to become reality. Copper can selectively inhibit rotifers in algae ponds, thereby protecting the algae crop. Differential toxicity tests were conducted to compare the copper sensitivity of a model rotifer—B. calyciflorus and an alga, C. kessleri. The rotifer LC50 was <0.1 ppm while the alga was not affected up to 5 ppm Cu(II. The low pH of the rotifer stomach may make it more sensitive to copper. However, when these cultures were combined, a copper concentration of 1.5 ppm was needed to inhibit the rotifer as the alga bound the copper, decreasing its bioavailability. Copper (X ppm had no effect on downstream fatty acid methyl ester extraction.

  13. Chlorella: 125 years of the green survivalist.

    Science.gov (United States)

    Krienitz, Lothar; Huss, Volker A R; Bock, Christina

    2015-02-01

    Chlorella, the archetype of unicellular green algae, is a high-performance primary producer in aquatic and terrestrial ecosystems. Under the simple spherical morphology of Chlorella, many other 'green balls' unfolded as independent phylogenetic lineages as a result of convergent evolution. By contrast, green algae with strikingly different phenotypes were unmasked as close relatives of Chlorella by modern molecular techniques. Here, we point to the increasing impact of these diverse protists on ecology, evolution, and biotechnology in the light of integrative taxonomy.

  14. Cultivation of Microalgae Chlorella sp. and Scenedesmus sp. as a Potentional Biofuel Feedstock

    Directory of Open Access Journals (Sweden)

    Prof. dr. Violeta Makareviciene

    2011-10-01

    Full Text Available The growth of two robust algae strains Chlorella sp. and Scenedesmus sp. growing in Lithuanian lakes was investigated with the aim to obtain optimum conditions for biomass cultivation for biofuel production in the Lithuanian environment. Samples were taken from different nitrogen sources and of different concentrations, with addition of various concentrations of CO2 and in the presence of salt. The best biomass productivity was achieved using urea as a nitrogen source or modified growing medium BG11 with decreased concentration of NaNO3. The positive impact on the growth of biomass was achieved by aeration with CO2 (especially with concentration of 24%. Additional research into the removal of pollutants, such inorganic salts of nitrogen and phosphorus and organic materials from wastewater using microalgae has revealed good possibilities of using both algae strains in wastewater treatment plants. A content of oil in Chlorella sp. and Scenedesmus sp. has suggested their potential use as biodiesel feedstock.

  15. THE POSSIBILITY OF USING WASTEWATER FOR THE PRODUCTION OF PLATYMONAS SUBCORDIFORMIS ALGAE BIOMASS

    Directory of Open Access Journals (Sweden)

    Magda Dudek

    2016-06-01

    Full Text Available The aim of the research was to determine the possibility of treated dairy wastewater using in the process of microalgae Platymonas subcordiformis biomass production. Researches were conducted in the laboratory scale with vertical photobioreactors using. Experiment was divided on the three variants based on the amount of wastewater introduced to culture medium. The researches proved the tested wastewater can be used in the intensive culture biomass of microalgae Platymonas subcordiformis. The highest technological effects associated with the increase in algal biomass obtained in the control sample where the concentration of algae cells at the end of the expansion process was nearly 3500 mgs.m.o./dm3. In embodiments using waste water as a component of the culture medium obtained microalgae increase over 2000 mgs.m.o./dm3.

  16. Nutrients and pharmaceuticals removal from wastewater by culture and harvesting of Chlorella sorokiniana.

    Science.gov (United States)

    Escapa, C; Coimbra, R N; Paniagua, S; García, A I; Otero, M

    2015-06-01

    This work aimed to study both the removal of nutrients and pharmaceuticals, namely salicylic acid or paracetamol, from water by the culture of Chlorella sorokiniana. The removal of nutrients was nearly complete at the end of the batch culture; above 70% for nitrates and 89% for phosphates in the semicontinuous culture. The pharmaceuticals removal kinetics were 2.3 times greater for the salicylic acid than paracetamol, reaching volumetric efficiencies above 93% for salicylic acid in the semicontinuous culture. Finally, to separate the microalgae biomass from treated water, metal salts, synthetic polyelectrolytes and a biopolymer were tested as coagulants-flocculants. The best flocculation results were achieved with AlCl3 (95.23% with 200mgg(-1), 1min incubation time). However, given that resulting flocs had different characteristics, flocculants must be chosen on the basis of the subsequent use of the biomass.

  17. Cultivation of Chlorella vulgaris and Arthrospira platensis with recovered phosphorus from wastewater by means of zeolite sorption.

    Science.gov (United States)

    Markou, Giorgos; Depraetere, Orily; Vandamme, Dries; Muylaert, Koenraad

    2015-02-16

    In this study, zeolite was employed for the separation and recovery of P from synthetic wastewater and its use as phosphorus (P) source for the cultivation of the green microalga Chlorella vulgaris and the cyanobacterium Arthrospira (Spirulina) platensis. At P-loaded zeolite concentration of 0.15-1 g/L, in which P was limited, the two species displayed quite different behavior regarding their growth and biomass composition. C. vulgaris preferred to increase the intracellular P and did not synthesize biomass, while A. platensis synthesized biomass keeping the intracellular P as low as possible. In addition under P limitation, C. vulgaris did display some little alteration of the biomass composition, while A. platensis did it significantly, accumulating carbohydrates around 70% from about 15%-20% (control). Both species could desorb P from zeolite biologically. A. platensis could recover over 65% and C. vulgaris 25% of the P bounded onto zeolite. When P-loaded zeolite concentration increased to 5 g/L, P was adequate to support growth for both species. Especially in the case of C. vulgaris, growth was stimulated from the presence of P-loaded zeolite and produced more biomass compared to the control.

  18. Studies on influence of process parameters on hydrothermal catalytic liquefaction of microalgae (Chlorella vulgaris) biomass grown in wastewater.

    Science.gov (United States)

    Arun, Jayaseelan; Shreekanth, Sivaraman Jayachandran; Sahana, Ravishankar; Raghavi, Meenakshi Sundaram; Gopinath, Kannappan Panchamoorthy; Gnanaprakash, Dhakshinamoorthy

    2017-08-12

    In this study, liquefaction of Chlorella vulgaris biomass grown in photo-bioreactor using wastewater as source of nutrition was studied and influence of process parameters on the yield of bio-oil was analysed. Different biomass to water ratio (5g/200ml, 10g/200ml, 15g/200ml, and 20g/200ml) was taken and bio-oil yield at various temperatures ranging from 220 to 340°C was studied. Catalyst loading of the range 2.5-8%wt of NaOH was also studied to analyse the influence of catalyst concentration on bio-oil yield. Obtained bio-oil was characterized using Gas Chromatography Mass Spectroscopy (GC-MS) and Fourier Transform Infrared Spectroscopy (FTIR). Results showed that maximum bio-oil yield of 26.67%wt was observed at operating conditions of 300°C, 15g/200ml biomass load and 2.5%wt of NaOH at 60min holding time. Fatty acids and other high carbon compounds were detected in the bio-oil obtained through liquefaction process. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Cultivation of Chlorella vulgaris and Arthrospira platensis with Recovered Phosphorus from Wastewater by Means of Zeolite Sorption

    Directory of Open Access Journals (Sweden)

    Giorgos Markou

    2015-02-01

    Full Text Available In this study, zeolite was employed for the separation and recovery of P from synthetic wastewater and its use as phosphorus (P source for the cultivation of the green microalga Chlorella vulgaris and the cyanobacterium Arthrospira (Spirulina platensis. At P-loaded zeolite concentration of 0.15–1 g/L, in which P was limited, the two species displayed quite different behavior regarding their growth and biomass composition. C. vulgaris preferred to increase the intracellular P and did not synthesize biomass, while A. platensis synthesized biomass keeping the intracellular P as low as possible. In addition under P limitation, C. vulgaris did display some little alteration of the biomass composition, while A. platensis did it significantly, accumulating carbohydrates around 70% from about 15%–20% (control. Both species could desorb P from zeolite biologically. A. platensis could recover over 65% and C. vulgaris 25% of the P bounded onto zeolite. When P-loaded zeolite concentration increased to 5 g/L, P was adequate to support growth for both species. Especially in the case of C. vulgaris, growth was stimulated from the presence of P-loaded zeolite and produced more biomass compared to the control.

  20. A MULTISTAGE GRADUAL NITROGENREDUCTION STRATEGY FOR INCREASED LIPID PRODUCTIVITY AND NITROGEN REMOVAL IN WASTEWATER USING Chlorella vulgaris AND Scenedesmus obliquus

    Directory of Open Access Journals (Sweden)

    J. C. Robles-Heredia

    2015-06-01

    Full Text Available AbstractChlorella vulgaris and Scenedesmus obliquuswere grown in artificial-wastewater using a new nitrogen-limitation strategy aimed at increasing lipid productivity. This strategy consisted in a multi-stage process with sequential reduction of N-NH4 concentration (from 90 to 60, 40, and 20 mg.L-1 to promote a balance between cell growth and lipid accumulation. Lipid productivity was compared against a reference process consisting of nitrogen reduction in two stages, where the nitrogen concentration was suddenly reduced from 90 mg.L-1 to three different concentrations (10, 20, and 30 mg.L-1. In the multi-stage mode, only C. vulgaris exhibited a net lipid-productivity increase. Lipid content of S. obliquus did not present a significant increase, thus decreasing lipid productivity. The highest lipid productivities were observed in the two-stage mode for both S. obliquus and C. vulgaris (194.9 and 133.5 mg.L-1.d-1, respectively, and these values are among the highest reported in the literature to date.

  1. Hydrothermal liquefaction of municipal wastewater cultivated algae: Increasing overall sustainability and value streams of algal biofuels

    Science.gov (United States)

    Roberts, Griffin William

    The forefront of the 21st century presents ongoing challenges in economics, energy, and environmental remediation, directly correlating with priorities for U.S. national security. Displacing petroleum-derived fuels with clean, affordable renewable fuels represents a solution to increase energy independence while stimulating economic growth and reducing carbon-based emissions. The U.S. government embodied this goal by passing the Energy Independence and Security Act (EISA) in 2007, mandating 36 billion gallons of annual biofuel production by 2022. Algae possess potential to support EISA goals and have been studied for the past 30-50 years as an energy source due to its fast growth rates, noncompetitive nature to food markets, and ability to grow using nutrient waste streams. Algae biofuels have been identified by the National Research Council to have significant sustainability concerns involving water, nutrient, and land use. Utilizing municipal wastewater to cultivate algae provides both water and nutrients needed for growth, partially alleviating these concerns. This dissertation demonstrates a pathway for algae biofuels which increases both sustainability and production of high-value products. Algae are cultivated in pilot-scale open ponds located at the Lawrence Wastewater Treatment Plant (Lawrence, KS) using solely effluent from the secondary clarifier, prior to disinfection and discharge, as both water and nutrient sources. Open ponds were self-inoculated by wastewater effluent and produced a mixed-species culture of various microalgae and macroalgae. Algae cultivation provided further wastewater treatment, removing both nitrogen and phosphorus, which have devastating pollution effects when discharged to natural watersheds, especially in large draining watersheds like the Gulf Coast. Algae demonstrated significant removal of other trace metals such as iron, manganese, barium, aluminum, and zinc. Calcium did not achieve high removal rate but did present a

  2. 利用啤酒废水培养普通小球藻生产微藻生物质和油脂%Cultivation of Chlorella vulgaris in brewery wastewater for production of microalgal biomass and lipid

    Institute of Scientific and Technical Information of China (English)

    曹海; 张馨允; 孔维宝; 杨红; 杨琪; 王科荣

    2012-01-01

    研究了普通小球藻在未处理啤酒废水及改良啤酒废水中的生长及积累油脂特性,并优化了改良啤酒废水培养小球藻的营养盐组成.优化得到适于培养小球藻生产微藻生物质和积累油脂的改良啤酒废水培养基组成为:在未经处理的啤酒废水中添加KNO3 0.50 g/L、MgSO4 0.75 g/L、Na2HPO4 0.75 g/L,调整pH至8.0.在此培养基中小球藻细胞质量浓度达0.94 g/L,为对照组的2.69倍;体积油脂产率达11.84 mg/(L·d),为对照组的1.97倍.研究表明,利用改良的啤酒废水培养小球藻可同时实现有机废水的资源化利用与降低微藻培养成本的双重目的,具有潜在的应用前景.%The growth characteristics and lipid accumulation of Chlorella vulgaris in crude and modified brewery wastewater(BWW) were investigated. Furthermore, the modified BWW medium components were optimized. The results indicated that the optimized components of modified BWW medium for biomass production and lipid accumulation were that KNO3 (0. 50 g/L) , MgSO4 (0. 75 g/L) and Na2HPO4 (0.75 g/L) were added in crude BWW and the pH value was adjusted to 8.0. The biomass content of 0. 94 g/L( 2. 69 - fold compared with control) and the lipid productivity of 11. 84 mg/ ( L o d ) ( 1. 97 -. fold compared with control) were obtained in the modified BWW medium. The study suggested that cultivation of Chlorella vulgaris with organic wastewater exhibited potential application prospect since it could couple the resource utilization of organic wastewater and cost reduction of algae cultivation.

  3. Synergistic effect of auxins and brassinosteroids on the growth and regulation of metabolite content in the green alga Chlorella vulgaris (Trebouxiophyceae).

    Science.gov (United States)

    Bajguz, Andrzej; Piotrowska-Niczyporuk, Alicja

    2013-10-01

    The relationships between brassinosteroids (BRs) (brassinolide, BL; 24-epiBL; 28-homoBL; castasterone, CS; 24-epiCS; 28-homoCS) and auxins (indole-3-acetic acid, IAA; indole-3-butyric acid, IBA; indole-3-propionic acid, IPA) in the regulation of cell number, phytohormone level and metabolism in green alga Chlorella vulgaris were investigated. Exogenously applied auxins had the highest biological activity in algal cells at 50 μM. Among the auxins, IAA was characterized by the highest activity, while IBA - by the lowest. BRs at 0.01 μM were characterized by the highest biological activity in relation to auxin-treated and untreated cultures of C. vulgaris. The application of 50 μM IAA stimulated the level of all detected endogenous BRs in C. vulgaris cells. The stimulatory effect of BRs in green algae was arranged in the following order: BL > 24-epiBL > 28-homoBL > CS > 24-epiCS > 28-homoCS. Auxins cooperated synergistically with BRs stimulating algal cell proliferation and endogenous accumulation of proteins, chlorophylls and monosaccharides in C. vulgaris. The highest stimulation of algal growth and the contents of analyzed biochemical parameters were observed for the mixture of BL with IAA, whereas the lowest in the culture treated with both 28-homoCS and IBA. However, regardless of the applied mixture of BRs with auxins, the considerable increase in cell number and the metabolite accumulation was found above the level obtained in cultures treated with any single phytohormone. Obtained results confirm that both groups of plant hormones cooperate synergistically in the control of growth and metabolism of unicellular green alga C. vulgaris.

  4. The Effect of Copper and Selenium Nanocarboxylates on Biomass Accumulation and Photosynthetic Energy Transduction Efficiency of the Green Algae Chlorella Vulgaris.

    Science.gov (United States)

    Mykhaylenko, Natalia F; Zolotareva, Elena K

    2017-12-01

    Nanoaquachelates, the nanoparticles with the molecules of water and/or carboxylic acids as ligands, are used in many fields of biotechnology. Ultra-pure nanocarboxylates of microelements are the materials of spatial perspective. In the present work, the effects of copper and selenium nanoaquachelates carboxylated with citric acid on biomass accumulation of the green algae Chlorella vulgaris were examined. Besides, the efficiency of the reactions of the light stage of photosynthesis was estimated by measuring chlorophyll a fluorescence. The addition of 0.67-4 mg L(-1) of Cu nanocarboxylates resulted in the increase in Chlorella biomass by ca. 20%; however, their concentrations ranging from 20 to 40 mg L(-1) strongly inhibited algal growth after the 12th day of cultivation. Se nanocarboxylates at 0.4-4 mg L(-1) concentrations also stimulated the growth of C. vulgaris, and the increase in biomass came up to 40-45%. The addition of Se nanocarboxylates at smaller concentrations (0.07 or 0.2 mg L(-1)) at first caused the retardation of culture growth, but that effect disappeared after 18-24 days of cultivation. The addition of 2-4 mg L(-1) of Cu nanocarboxylates or 0.4-4 mg L(-1) of Se nanocarboxylates caused the evident initial increase in such chlorophyll a fluorescence parameters as maximal quantum yield of photosystem II photochemistry (F v/F m) and the quantum yield of photosystem II photochemistry in the light-adapted state (F v'/F m'). Photochemical fluorescence quenching coefficients declined after 24 days of growth with Cu nanocarboxylates, but they increased after 6 days of the addition of 2 or 4 mg L(-1) Se nanocarboxylates. Those alterations affected the overall quantum yield of the photosynthetic electron transport in photosystem II.

  5. The Effect of Copper and Selenium Nanocarboxylates on Biomass Accumulation and Photosynthetic Energy Transduction Efficiency of the Green Algae Chlorella Vulgaris

    Science.gov (United States)

    Mykhaylenko, Natalia F.; Zolotareva, Elena K.

    2017-02-01

    Nanoaquachelates, the nanoparticles with the molecules of water and/or carboxylic acids as ligands, are used in many fields of biotechnology. Ultra-pure nanocarboxylates of microelements are the materials of spatial perspective. In the present work, the effects of copper and selenium nanoaquachelates carboxylated with citric acid on biomass accumulation of the green algae Chlorella vulgaris were examined. Besides, the efficiency of the reactions of the light stage of photosynthesis was estimated by measuring chlorophyll a fluorescence. The addition of 0.67-4 mg L-1 of Cu nanocarboxylates resulted in the increase in Chlorella biomass by ca. 20%; however, their concentrations ranging from 20 to 40 mg L-1 strongly inhibited algal growth after the 12th day of cultivation. Se nanocarboxylates at 0.4-4 mg L-1 concentrations also stimulated the growth of C. vulgaris, and the increase in biomass came up to 40-45%. The addition of Se nanocarboxylates at smaller concentrations (0.07 or 0.2 mg L-1) at first caused the retardation of culture growth, but that effect disappeared after 18-24 days of cultivation. The addition of 2-4 mg L-1 of Cu nanocarboxylates or 0.4-4 mg L-1 of Se nanocarboxylates caused the evident initial increase in such chlorophyll a fluorescence parameters as maximal quantum yield of photosystem II photochemistry ( F v/ F m) and the quantum yield of photosystem II photochemistry in the light-adapted state ( F v'/ F m'). Photochemical fluorescence quenching coefficients declined after 24 days of growth with Cu nanocarboxylates, but they increased after 6 days of the addition of 2 or 4 mg L-1 Se nanocarboxylates. Those alterations affected the overall quantum yield of the photosynthetic electron transport in photosystem II.

  6. De-eutrophication of effluent wastewater from fish aquaculture by using marine green alga Ulva pertusa

    Institute of Scientific and Technical Information of China (English)

    刘建国; 王增福; 林伟

    2010-01-01

    The de-eutrophication abilities and characteristics of Ulva pertusa, a marine green alga, were investigated in Qingdao Yihai Hatchery Center from spring to summer in 2005 by analyzing the dynamic changes in NH+4, NOˉ3, NO2ˉ as well as the total dissolved inorganic nitrogen (DIN). The results show that the effluent wastewater produced by fish aquaculture had typical eutrophication levels with an average of 34.3 μmol L-1 DIN. This level far exceeded the level IV quality of the national seawater standard and c...

  7. Offshore Membrane Enclosures for Growing Algae (OMEGA: A System for Biofuel Production, Wastewater Treatment, and CO2 Sequestration

    Science.gov (United States)

    Trent, Jonathan; Embaye, Tsegereda; Buckwalter, Patrick; Richardson, Tra-My; Kagawa, Hiromi; Reinsch, Sigrid; Martis, Mary

    2010-01-01

    We are developing Offshore Membrane Enclosures for Growing Algae (OMEGA). OMEGAs are closed photo-bioreactors constructed of flexible, inexpensive, and durable plastic with small sections of semi-permeable membranes for gas exchange and forward osmosis (FO). Each OMEGA modules is filled with municipal wastewater and provided with CO2 from coastal CO2 sources. The OMEGA modules float just below the surface, and the surrounding seawater provides structural support, temperature control, and mixing for the freshwater algae cultures inside. The salinit7 gradient from inside to outside drives forward osmosis through the patches of FO membranes. This concentrates nutrients in the wastewater, which enhances algal growth, and slowly dewaters the algae, which facilitates harvesting. Thy concentrated algal biomass is harvested for producing biofuels and fertilizer. OMEGA system cleans the wastewater released into the surrounding coastal waters and functions as a carbon sequestration system.

  8. Evaluating the potential of renewable diesel production from algae cultured on wastewater: techno-economic analysis and life cycle assessment

    Directory of Open Access Journals (Sweden)

    Ankita Juneja

    2017-03-01

    Full Text Available Algae, a renewable energy source, has an added advantage of consuming nutrients from wastewater and consequently aiding in wastewater treatment. The algae thus produced can be processed using alternative paths for conversion to fuels. However, due to high moisture content of algae, wet algae processing methods are being encouraged to avoid the dewatering cost and energy. Hydrothermal liquefaction is one such technology that converts the algae into high heating value bio-oil under high temperature and pressure. This bio-oil can be further upgraded to renewable diesel (RD which can be used in diesel powered vehicles without any modifications. The objective of this study is to evaluate the economic viability and to estimate the energy use and greenhouse gas (GHG emissions during life cycle of RD production from algae grown in wastewater using hydrothermal liquefaction. Economic analysis of RD production on commercial scale was performed using engineering process model of RD production plant with processing capacity of 60 Mgal wastewater/day, simulated in SuperPro designer. RD yields for algae were estimated as 10.18 MML/year with unit price of production as $1.75/RD. The GHG emissions during life cycle of RD production were found to be 6.2 times less than those produced for conventional diesel. Sensitivity analysis indicated a potential to reduce ethanol production cost either by using high lipid algae or increasing the plant size. The integrated economic and ecological assessment analyses are helpful in determining long-term sustainability of a product and can be used to drive energy policies in an environmentally sustainable direction.

  9. Growth and nutrient removal in free and immobilized green algae in batch and semi-continuous cultures treating real wastewater.

    Science.gov (United States)

    Ruiz-Marin, Alejandro; Mendoza-Espinosa, Leopoldo G; Stephenson, Tom

    2010-01-01

    Two species of microalgae growing as immobilized and free-cells were compared to test its ability to remove N and P in batch cultures of urban wastewater. The best microalgae-cell growth configuration was selected to be tested in bioreactor operated in semi-continuous mode. Scenedesmus obliquus showed a higher N and P uptake rate in urban wastewater than Chlorella vulgaris. When tested in semi-continuous mode and with the re-calcification of beads, S. obliquus was more effective in removing N and P for longer periods (181 h) than batch cultures; fecal coliforms removal was good (95%) although the final concentration was still unsuitable for discharge to natural water bodies. Protein and lipids content analysis suggest that, from a practical point of view, immobilized systems could facilitate the separation of the biomass from the treated wastewater although in terms of nutritional value of the biomass, immobilized systems do not represent an advantage over free-cell systems.

  10. Effective and selective recovery of gold and palladium ions from metal wastewater using a sulfothermophilic red alga, Galdieria sulphuraria

    OpenAIRE

    2016-01-01

    The demand for precious metals has increased in recent years. However, low concentrations of precious metals dissolved in wastewater are yet to be recovered because of high operation costs and technical problems. The unicellular red alga, Galdieria sulphuraria, efficiently absorbs precious metals through biosorption. In this study, over 90% of gold and palladium could be selectively recovered from aqua regia-based metal wastewater by using G. sulphuraria. These metals were eluted from the cel...

  11. Acetyl-CoA synthetase is activated as part of the PDH-bypass in the oleaginous green alga Chlorella desiccata.

    Science.gov (United States)

    Avidan, Omri; Pick, Uri

    2015-12-01

    In a recent study, it has been shown that biosynthesis of triacylglycerol (TAG) in the oleaginous green alga Chlorella desiccata is preceded by a large increase in acetyl-coenzyme A (Ac-CoA) levels and by upregulation of plastidic pyruvate dehydrogenase (ptPDH). It was proposed that the capacity to accumulate high TAG critically depends on enhanced production of Ac-CoA. In this study, two alternative Ac-CoA producers-plastidic Ac-CoA synthase (ptACS) and ATP citrate lyase (ACL)-are shown to be upregulated prior to TAG accumulation under nitrogen deprivation in the oleaginous species C. desiccata, but not in the moderate TAG accumulators Dunaliella tertiolecta and Chlamydomonas reinhardtii. Measurements of endogenous acetate production and of radiolabelled acetate incorporation into lipids are consistent with the upregulation of ptACS, but suggest that its contribution to the overall TAG biosynthesis is negligible. Induction of ACS and production of endogenous acetate are correlated with activation of alcohol dehydrogenase, suggesting that the upregulation of ptACS is associated with activation of PDH-bypass in C. desiccata. It is proposed that activation of the PDH-bypass in C. desiccata is needed to enable a high rate of lipid biosynthesis under nitrogen deprivation by controlling the level of pyruvate reaching ptPHD and/or mtPDH. This may be an important parameter for massive TAG accumulation in microalgae.

  12. Harvesting, oil extraction, and conversion of local filamentous algae growing in wastewater into biodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Grayburn, W.S.; Holbrook, G.P. [Department of Biological Sciences, Northern Illinois University, DeKalb, IL 60115 (United States); Tatara, R.A. [Department of Technology, Northern Illinois University, DeKalb, IL 60115 (United States); Rosentrater, K.A. [Department of Agricultural and Biosystems Engineering, Iowa State University, Ames, IA 50011 (United States)

    2013-07-01

    Algae are known to be a potential feedstock in the production of biodiesel fuel. Although much of the focus has been on microalgal species, macroalgae are also suitable as a source of lipids. In this study, a locally abundant (central Illinois) filamentous algae has been harvested from a water treatment plant; dried to about 10% of its initial weight; pulverized in a hammermill; and treated with methanol to extract the oil. The algae are a combination of several coexisting species including Cladophora sp. and Rhizoclonium. Oil yields ranged from 3% to 6%, by weight, of the dried mass. This oil was reacted by transesterification to yield fatty acid methyl esters (biodiesel fuel) with an overall mass conversion efficiency of 68%. A B5 blend of this algal biodiesel and petrodiesel was run in a 13.4-kW test engine. Measurements indicated similar performance compared to pure petrodiesel in terms of fuel efficiency and carbon dioxide and carbon monoxide exhaust emissions. Significantly, there was a 22% reduction in nitrogen oxides when using the B5 fuel. It has been demonstrated that filamentous macroalgae may be cultivated as biodiesel feedstock and have inherent advantages such as an ability to remove phosphorus and nitrogen compounds from wastewater, simplicity of harvesting, and natural resistance to local aquatic grazers and competing organisms.

  13. Physical pretreatments of wastewater algae to reduce ash content and improve thermal decomposition characteristics.

    Science.gov (United States)

    Chen, Wan-Ting; Ma, Junchao; Zhang, Yuanhui; Gai, Chao; Qian, Wanyi

    2014-10-01

    Previous study showed high ash content in wastewater algae (WA) has a negative effect on bio-crude oil formation in hydrothermal liquefaction (HTL). This study explored the effect of different pretreatments on ash reduction and the thermal decomposition of WA. Single-stage (e.g. centrifugation) and two-stage pretreatments (e.g. centrifugation followed by ultrasonication, C+U) were used. The apparent activation energy of the thermal decomposition (E(a)) of pretreated algae was determined. HTL was conducted to study how different pretreatments may impact on bio-crude oil formation. Compared to untreated samples, the ash content of algae with centrifugation was reduced from 28.6% to 18.6%. With C+U pretreatments, E(a) was decreased from 50.2 kJ/mol to 35.9 kJ/mol and the bio-crude oil yield was increased from 30% to 55%. These results demonstrate that pretreatments of C+U can improve the thermal decomposition behavior of WA and enhance the bio-crude oil conversion efficiency. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Harvesting, oil extraction, and conversion of local filamentous algae growing in wastewater into biodiesel

    Directory of Open Access Journals (Sweden)

    W. S. Grayburn, R. A. Tatara, K. A. Rosentrater, G. P. Holbrook

    2013-01-01

    Full Text Available Algae are known to be a potential feedstock in the production of biodiesel fuel. Although much of the focus has been on microalgal species, macroalgae are also suitable as a source of lipids. In this study, a locally abundant (central Illinois filamentous algae has been harvested from a water treatment plant; dried to about 10% of its initial weight; pulverized in a hammermill; and treated with methanol to extract the oil. The algae are a combination of several coexisting species including Cladophora sp. and Rhizoclonium. Oil yields ranged from 3% to 6%, by weight, of the dried mass. This oil was reacted by transesterification to yield fatty acid methyl esters (biodiesel fuel with an overall mass conversion efficiency of 68%. A B5 blend of this algal biodiesel and petrodiesel was run in a 13.4-kW test engine. Measurements indicated similar performance compared to pure petrodiesel in terms of fuel efficiency and carbon dioxide and carbon monoxide exhaust emissions. Significantly, there was a 22% reduction in nitrogen oxides when using the B5 fuel. It has been demonstrated that filamentous macroalgae may be cultivated as biodiesel feedstock and have inherent advantages such as an ability to remove phosphorus and nitrogen compounds from wastewater, simplicity of harvesting, and natural resistance to local aquatic grazers and competing organisms.

  15. Enhanced lipidic algae biomass production using gas transfer from a fermentative Rhodosporidium toruloides culture to an autotrophic Chlorella protothecoides culture.

    Science.gov (United States)

    Santos, C A; Caldeira, M L; Lopes da Silva, T; Novais, J M; Reis, A

    2013-06-01

    In order to produce single-cell oil for biodiesel, a yeast and a microalga were, for the first time, grown in two separate reactors connected by their gas-phases, taking advantage of their complementary nutritional metabolisms, i.e., respiration and photosynthesis. The yeast Rhodosporidium toruloides was used for lipid production, originating a carbon dioxide-enriched outlet gas stream which in turn was used to stimulate the autotrophic growth of Chlorella protothecoides in a vertical-alveolar-panel (VAP) photobioreactor. The microalgal biomass productivity was 0.015 gL(-1)h(-1), and its lipid productivity attained 2.2 mgL(-1)h(-1) when aerated with the outlet gas stream from the yeast fermenter. These values represent an increase of 94% and 87%, respectively, as compared to a control culture aerated with air. The CO2 bio-fixed by the microalgal biomass reached an estimated value of 29 mgL(-1)h(-1) in the VAP receiving the gas stream from the fermenter, a value 1.9 times higher than that measured in the control VAP.

  16. De-eutrophication of effluent wastewater from fish aquaculture by using marine green alga Ulva pertusa

    Science.gov (United States)

    Liu, Jianguo; Wang, Zengfu; Lin, Wei

    2010-03-01

    The de-eutrophication abilities and characteristics of Ulva pertusa, a marine green alga, were investigated in Qingdao Yihai Hatchery Center from spring to summer in 2005 by analyzing the dynamic changes in NH{4/+}, NO{3/-}, NO{2/-} as well as the total dissolved inorganic nitrogen (DIN). The results show that the effluent wastewater produced by fish aquaculture had typical eutrophication levels with an average of 34.3 μmol L-1 DIN. This level far exceeded the level IV quality of the national seawater standard and could easily lead to phytoplankton blooms in nature if discarded with no treatment. The de-eutrophication abilities of U. pertusa varied greatly and depended mainly on the original eutrophic level the U. pertusa material was derived from. U. pertusa used to living in low DIN conditions had poor DIN removal abilities, while materials cultured in DIN-enriched seawater showed strong de-eutrophication abilities. In other words, the de-eutrophication ability of U. pertusa was evidently induced by high DIN levels. The de-eutrophication capacity of U. pertusa seemed to also be light dependent, because it was weaker in darkness than under illumination. However, no further improvement in the de-eutrophication capacity of U. pertusa was observed once the light intensity exceeded 300 μmol M2 S-1. Results of semi-continuous wastewater replacement experiments showed that U. pertusa permanently absorbed nutrients from eutrophicated wastewater at a mean rate of 299 mg/kg fresh weight per day (126 mg/kg DIN during the night, 173 mg/kg in daytime). Based on the above results, engineered de-eutrophication of wastewater by using a U. pertusa filter system seems feasible. The algal quantity required to purify all the eutrophicated outflow wastewater from the Qingdao Yihai Hatchery Center into oligotrophic level I clean seawater was also estimated using the daily discharged wastewater, the average DIN concentration released and the de-eutrophication capacity of U. pertusa.

  17. Influences of iron and calcium carbonate on wastewater treatment performances of algae based reactors.

    Science.gov (United States)

    Zhao, Zhimiao; Song, Xinshan; Wang, Wei; Xiao, Yanping; Gong, Zhijie; Wang, Yuhui; Zhao, Yufeng; Chen, Yu; Mei, Mengyuan

    2016-09-01

    The influences of iron and calcium carbonate (CaCO3) addition in wastewater treatments reactors performance were investigated. Adding different concentrations of Fe(3+) (5, 10, 30 and 50mmol/m(3)), iron and CaCO3 powder led to changes in algal characteristics and physico-chemical and microbiological properties. According to the investigation results, nutrient removal efficiency in algae based reactors was obviously increased by the addition of 10mmol/m(3) Fe(3+), iron (5mmol/m(3)) and CaCO3 powder (0.2gm(-3)) and the removal efficiencies of BOD5, TN, and TP in Stage 2 were respectively increased by 28%, 8.9%, and 22%. The improvements in physico-chemical performances were verified by microbial community tests (bacteria quantity, activity and community measured in most probable number, extracellular enzymes activity, and Biolog Eco Plates). Microbial variations indicated the coexistence of Fe ions and carbonate-bicarbonate, which triggered the synergistic effect of physico-chemical action and microbial factors in algae based reactors. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Biosorption of U(VI) by the green algae Chlorella vulgaris in dependence of pH value and cell activity

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, M., E-mail: M.Vogel@fzd.de; Guenther, A.; Rossberg, A.; Li, B.; Bernhard, G.; Raff, J.

    2010-12-15

    Biosorption of uranium(VI) by the green alga Chlorella vulgaris was studied at varying uranium concentrations from 5 {mu}M to 1 mM, and in the environmentally relevant pH range of 4.4 to 7.0. Living cells bind in a 0.1 mM uranium solution at pH 4.4 within 5 min 14.3 {+-} 5.5 mg U/g dry biomass and dead cells 28.3 {+-} 0.6 mg U/g dry biomass which corresponds to 45% and 90% of total uranium in solution, respectively. During 96 h of incubation with uranium initially living cells died off and with 26.6 {+-} 2.1 mg U/g dry biomass bound similar amounts of uranium compared to dead cells, binding 27.0 {+-} 0.7 mg U/g dry biomass. In both cases, these amounts correspond to around 85% of the initially applied uranium. Interestingly, at a lower and more environmentally relevant uranium concentration of 5 {mu}M, living cells firstly bind with 1.3 {+-} 0.2 mg U/g dry biomass to 1.4 {+-} 0.1 mg U/g dry biomass almost all uranium within the first 5 min of incubation. But then algal cells again mobilize up to 80% of the bound uranium during ongoing incubation in the time from 48 h to 96 h. The release of metabolism related substances is suggested to cause this mobilization of uranium. As potential leachates for algal-bound uranium oxalate, citrate and ATP were tested and found to be able to mobilize more than 50% of the algal-bound uranium within 24 h. Differences in complexation of uranium by active and inactive algae cells were investigated with a combination of time-resolved laser-induced fluorescence spectroscopy (TRLFS), extended X-ray absorption fine structure (EXAFS) spectroscopy and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. Obtained results demonstrated an involvement of carboxylic and organic/inorganic phosphate groups in the uranium complexation with varying contributions dependent on cell status, uranium concentration and pH.

  19. PYROLYSIS OF ALGAL BIOMASS OBTAINED FROM HIGH RATE ALGAE PONDS APPLIED TO WASTEWATER TREATMENT

    Directory of Open Access Journals (Sweden)

    Fernanda eVargas E Silva

    2015-06-01

    Full Text Available This work presents the results of the pyrolysis of algal biomass obtained from high rate algae ponds treating sewage. The two high-rate algae ponds (HRAP were built and operated at the São João Navegantes Wastewater Treatment Plant. The HRAP A was fed with raw sewage while the HRAP B was fed with effluent from an Upflow Anaerobic Sludge Blanket (UASB reactor. The HRAP B provided higher productivity, presenting total solids concentration of 487.3mg/l and chlorophyll a of 7735mg/l. The algal productivity in the average depth was measured at 41,8 gm-2day-1 in pond A and at 47.1 gm-2day-1 in pond B. Algae obtained from the HRAP B were separated by the process of coagulation/flocculation and sedimentation. In the presence of alum, a separation efficiency in the range of 97% solids removal was obtained. After centrifugation the biomass was dried and comminuted. The biofuel production experiments were conducted via pyrolysis in a tubular quartz glass reactor which was inserted in a furnace for external heating. The tests were carried out in an inert nitrogen atmosphere at a flow rate of 60ml/min. The system was operated at 400°C, 500°C and 600°C in order to determine the influence of temperature on the obtained fractional yields. The studies showed that the pyrolysis product yield was influenced by temperature, with a maximum liquid phase (bio-oil and water production rate of 44% at 500°C, 45% for char and around 11% for gas.

  20. Air-drying of cells, the novel conditions for stimulated synthesis of triacylglycerol in a Green Alga, Chlorella kessleri.

    Directory of Open Access Journals (Sweden)

    Takuma Shiratake

    Full Text Available Triacylglycerol is used for the production of commodities including food oils and biodiesel fuel. Microalgae can accumulate triacylglycerol under adverse environmental conditions such as nitrogen-starvation. This study explored the possibility of air-drying of green algal cells as a novel and simple protocol for enhancement of their triacylglycerol content. Chlorella kessleri cells were fixed on the surface of a glass fibre filter and then subjected to air-drying with light illumination. The dry cell weight, on a filter, increased by 2.7-fold in 96 h, the corresponding chlorophyll content ranging from 1.0 to 1.3-fold the initial one. Concomitantly, the triacylglycerol content remarkably increased to 70.3 mole% of fatty acids and 15.9% (w/w, relative to total fatty acids and dry cell weight, respectively, like in cells starved of nitrogen. Reduction of the stress of air-drying by placing the glass filter on a filter paper soaked in H2O lowered the fatty acid content of triacylglycerol to 26.4 mole% as to total fatty acids. Moreover, replacement of the H2O with culture medium further decreased the fatty acid content of triacylglycerol to 12.2 mole%. It thus seemed that severe dehydration is required for full induction of triacylglycerol synthesis, and that nutritional depletion as well as dehydration are crucial environmental factors. Meanwhile, air-drying of Chlamydomonas reinhardtii cells increased the triacylglycerol content to only 37.9 mole% of fatty acids and 4.8% (w/w, relative to total fatty acids and dry cell weight, respectively, and a marked decrease in the chlorophyll content, on a filter, of 33%. Air-drying thus has an impact on triacylglycerol synthesis in C. reinhardtii also, however, the effect is considerably limited, owing probably to instability of the photosynthetic machinery. This air-drying protocol could be useful for the development of a system for industrial production of triacylglycerol with appropriate selection of the

  1. Air-drying of cells, the novel conditions for stimulated synthesis of triacylglycerol in a Green Alga, Chlorella kessleri.

    Science.gov (United States)

    Shiratake, Takuma; Sato, Atsushi; Minoda, Ayumi; Tsuzuki, Mikio; Sato, Norihiro

    2013-01-01

    Triacylglycerol is used for the production of commodities including food oils and biodiesel fuel. Microalgae can accumulate triacylglycerol under adverse environmental conditions such as nitrogen-starvation. This study explored the possibility of air-drying of green algal cells as a novel and simple protocol for enhancement of their triacylglycerol content. Chlorella kessleri cells were fixed on the surface of a glass fibre filter and then subjected to air-drying with light illumination. The dry cell weight, on a filter, increased by 2.7-fold in 96 h, the corresponding chlorophyll content ranging from 1.0 to 1.3-fold the initial one. Concomitantly, the triacylglycerol content remarkably increased to 70.3 mole% of fatty acids and 15.9% (w/w), relative to total fatty acids and dry cell weight, respectively, like in cells starved of nitrogen. Reduction of the stress of air-drying by placing the glass filter on a filter paper soaked in H2O lowered the fatty acid content of triacylglycerol to 26.4 mole% as to total fatty acids. Moreover, replacement of the H2O with culture medium further decreased the fatty acid content of triacylglycerol to 12.2 mole%. It thus seemed that severe dehydration is required for full induction of triacylglycerol synthesis, and that nutritional depletion as well as dehydration are crucial environmental factors. Meanwhile, air-drying of Chlamydomonas reinhardtii cells increased the triacylglycerol content to only 37.9 mole% of fatty acids and 4.8% (w/w), relative to total fatty acids and dry cell weight, respectively, and a marked decrease in the chlorophyll content, on a filter, of 33%. Air-drying thus has an impact on triacylglycerol synthesis in C. reinhardtii also, however, the effect is considerably limited, owing probably to instability of the photosynthetic machinery. This air-drying protocol could be useful for the development of a system for industrial production of triacylglycerol with appropriate selection of the algal species.

  2. Cultivation of Chlorella sp. using raw dairy wastewater for nutrient removal and biodiesel production: Characteristics comparison of indoor bench-scale and outdoor pilot-scale cultures.

    Science.gov (United States)

    Lu, Weidong; Wang, Zhongming; Wang, Xuewei; Yuan, Zhenhong

    2015-09-01

    The biomass productivity and nutrient removal capacity of simultaneous Chlorella sp. cultivation for biodiesel production and nutrient removal in raw dairy wastewater (RDW) in indoor bench-scale and outdoor pilot-scale photobioreactors were compared. Results from the current work show that maximum biomass productivity in indoor bench-scale cultures can reach 260 mg L(-1) day(-1), compared to that of 110 mg L(-1) day(-1) in outdoor pilot-scale cultures. Maximum chemical oxygen demand (COD), total nitrogen (TN), and total phosphorous (TP) removal rate obtained in indoor conditions was 88.38, 38.34, and 2.03 mg L(-1) day(-1), respectively, this compared to 41.31, 6.58, and 2.74 mg L(-1) day(-1), respectively, for outdoor conditions. Finally, dominant fatty acids determined to be C16/C18 in outdoor pilot-scale cultures indicated great potential for scale up of Chlorella sp. cultivation in RDW for high quality biodiesel production coupling with RDW treatment.

  3. Performance of mixed algae for treatment of slaughterhouse wastewater and microbial community analysis.

    Science.gov (United States)

    Taşkan, Ergin

    2016-10-01

    This study investigated organic matter (OM) and nutrient removal efficiency of mixed algal species from slaughterhouse wastewater (SWW) by using photo-bioreactor. For this purpose, different dilution multiples of 10, 4, and 2 were applied to the SWW, and pure wastewater was finally used for algal cultivation. OM and nutrient removal performance in an algal photo-bioreactor were severely affected by the dilution ratio. After 7 days of cultivation, the highest removal percentages of total organic carbon (TOC), total nitrogen (TN), and total phosphorus (TP) were 89.6, 70.2, and 96.2 %, respectively. Furthermore, the changes in eukaryotic algae and cyanobacterial species in the algal photo-bioreactors were investigated using polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) techniques. The results indicated that cyanobacterial species were more efficient than eukaryotic species in removing nutrients from the SWW. This study suggests that mixed algal photo-bioreactors could be used efficiently in the treatment of SWW.

  4. 蛋白核小球藻(Chlorella pyrenoidosa)Rubisco活化酶基因的克隆与表达分析%THE CLONING AND EXPRESSION ANALYSIS OF RUBISCO ACTIVASE GENE IN THE UNICELLULAR GREEN ALGA CHLORELLA PYRENOIDOSA

    Institute of Scientific and Technical Information of China (English)

    邓意龙; 孙雪; 徐年军; 杨锐

    2012-01-01

    RACE technology was employed to clone the Rubisco activase gene (rca) of the unicellular green alga Chlorella pyrenoidosa 820, and the rca and rbcS (small subunit of Rubisco) expression profiles were investigated by real-time PCR. The obtained 1703bp rca cDNA sequence contained a 66bp 5’-untranslated region, a 1242bp open reading frame and a 395bp 3’-untranslated region. Sequence comparison showed that its homology with other green algae reached to 78%—85%. Sequence analysis showed that the rca gene preferred to use the codons ended with G or C or T, and the putative isoelectric point and molecular weight was 8.44 and 45.71kDa, respectively. Real-time PCR showed that rca and rbcS transcription quantities decreased as the light duration time increased. Under different salinity stress, rbcS mRNA quantities showed no significant variation, while rca mRNA quantities in 37.5 salinity reached to 2.69 fold of those in 25 salinity. The transcriptional expression of rca and rbcS all decreased after 1.0, 2.0 and 3.0mmol/L salicylic acid treatments.%采用RACE技术克隆了单细胞绿藻蛋白核小球藻820Rubisco活化酶基因(rca)序列,并用荧光定量PCR方法研究了rca和Rubisco小亚基基因(rbcS)的表达规律。结果获得了1703bp的rcacDNA序列,包括66bp的5’非翻译区、1242bp的开放阅读框和395bp的3’非翻译区。序列比较和分析表明该蛋白核小球藻rca序列与其它绿藻的同源性高达78%—85%;偏好使用以G/C/T结尾的密码子;推测的RCA蛋白等电点和分子量分别为8.44和45.71kDa。荧光定量PCR结果表明随光照时间增加rca与rbcS转录表达逐渐降低;不同盐度处理下rbcS的mRNA量变化不大,而rca在37.5盐度下表达量为25盐度的2.69倍;1.0—3.0mmol/L水杨酸处理rca与rbcS表达均降低。

  5. Water-Nutrient-food Nexus The Role of Green Algae for Sustainable Food Production in Urban Wetlands Through Untreated Wastewater

    Directory of Open Access Journals (Sweden)

    Hussnain Mukhtar

    2016-02-01

    Full Text Available The nutrients in domestic wastewater are increasingly being regarded as a valuable resource for energy and nutrient recovery for an Eco-city. The nutrient stream can be used safely for food production through ecological engineering interventions (introduction of green algae in urban wetlands. Effects of wastewater on growth yield and microbial contamination on hydroponic tomato (Lycopersicon esculentum was studied in pilot scale wetland for 6 month under the presence of green algae (Euglena sp. with different chlorophyll a concentration. Domestic wastewater (BOD 205 mg.L-1, TN 29 mg.L-1 and TP 8 mg.L-1 with loading rate of 0.9 L.m-2.d-1 was used for each wetland. The wastewater did not affect fruit pH, increased their size up to 1.7 ± 0.31 cm in diameter, and weight up to 69.3 ± 6.0 g. Microbial contamination (Total coliforms (TC and Fecal coliforms (FC on fruit surface significantly decreased (p < 0.05 with the increasing algal concentration up to 240 μg.L-1. Inactivation of bacterial contamination (TC and FC under the presence of algae associated with high dissolved oxygen concentration (9.7 ± 1.1 mg.L-1 and pH increases (8.2 ± 0.8 attributes in wetland. In summary, tomato production in urban wetlands under the presence of green algae enhances the importance of safe and sustainable food production through untreated wastewater.

  6. [Using Excess Activated Sludge Treated 4-Chlorophenol Contained Waste Water to Cultivate Chlorella vulgaris].

    Science.gov (United States)

    Wang, Lu; Chen, Xiu-rong; Yan, Long; He, Yi-xuan; Shi, Zhen-dong

    2015-04-01

    Using different rations of sludge extracts and supernate from 4-Chlorophenol (4-CP) simulated wastewater's excess sludge after centrifugation to cultivate the Chlorella vulgaris to achieve the goal of excess sludge utilization together with chlorella cultivating. The experiments were performed in 500 mL flasks with different rations of sludge extracts & BG-11 and supernate & BG-11 in a light growth chamber respectively. Number of algal cells, Chlorophyll, enzyme activity, oil and water total nitrogen (TN), total phosphorus (TP), total organic carbon (TOC), toxicity index were investigated. Result showed that the nutrition supplies and toxicity in the excess sludge were removed efficiently via Chlorella vulgaris, the removal rates of TN and TP were at least 40% and 90% respectively; After 10 days cultivation, the density growth of 50% sludge extracts was 20 times higher of the beginning while its chlorophyll content was lower than that of the blank group. Sludge extracts could promote the proliferation of algae, but were not conducive to the synthesis of chlorophyll. The quantity of SOD in per cell showed Chlorella vulgaris gave a positive response via stimulation from toxicant in sludge extracts and supernate. The best time for collecting chlorella vulgaris was the fifth day of cultivation, taking neutral oil accumulation as the evaluating indicator for its utilization combined with the removal of supplies and toxicity.

  7. Is nitrogen loading in wastewater more important than phosphorus? A historic review of the relationship between algae and macrophyte biomass and wastewater nutrient loading in the Bow River

    Science.gov (United States)

    Taube, Nadine; He, Jianxun; Ryan, Cathy; Valeo, Caterina

    2014-05-01

    The role of nutrient loading on biomass growth in wastewater-impacted rivers is important in understanding how to most effectively optimize wastewater treatment to avoid excessive biomass growth in the receiving water body. Nutrient loading is also affected by the nature of the effluent mixing in the river. This paper relates ammonium (NH4), nitrate (NO3) and total phosphorus (TP) from a wastewater treatment plant (WWTP) to epilithic algae and macrophyte biomass for determination of impacts of the WWTP on the Bow River ecosystem in Calgary, Alberta. Annual macrophyte biomass data and WWTP effluent nutrient data was analyzed for the years from 1981 - 2011. Locally Weighted Scatterplot Smoothing (LOWESS) was used to remove the influence of the river discharge from the biomass. The LOWESS method indicates that macrophytes do not grow beyond a maximum annual discharge of 300m3s-1. Algae biomass was most significantly correlated to daily mean discharge on sampling date and the LOWESS method indicates that they do not grow well beyond a daily mean discharge of 100m3s-1. Correlation analysis suggests that biomass in the Bow River is nitrogen limited. Epilithic algae are significantly correlated (p

  8. Removal of Nitrogen and Phosphorus From Reject Water Using Chlorella vulgaris Algae After Partial Nitrification/Anammox Process.

    Science.gov (United States)

    Gutwinski, Piotr; Cema, Grzegorz

    2016-01-01

    Wastewater containing nutrients like ammonia, nitrite, nitrate and phosphates have been identified as the main cause of eutrophication in natural waters. Therefore, a suitable treatment is needed. In classical biological processes, nitrogen and phosphorus removal is expensive, especially due to the lack of biodegradable carbon, thus new methods are investigated. In this paper, the new possibility of nitrogen and phosphorus removal in side stream after the partial nitrification/Anammox process is proposed. Research was carried out in a lab-scale vertical tubular photobioreactor (VTR) fed with real reject water, from dewatering of digested sludge, after partial nitrification/Anammox process from lab-scale sequencing batch reactor (SBR). Nitrogen and phosphorus concentrations were measured every three days. The average nitrogen and phosphorus loads were 0.0503 ± 0.036 g N g(vss)/d and 0.0389 ± 0.013 g P g(vss)/d accordingly. Results have shown that microalgae were able to efficiently remove nitrogen and phosphorus. The average nitrogen removal was 36.46% and phosphorus removal efficiency varied between 93 and 100%.

  9. Relative importance of P and N in macrophyte and epilithic algae biomass in a wastewater-impacted oligotrophic river.

    Science.gov (United States)

    Taube, Nadine; He, Jianxun; Ryan, M Cathryn; Valeo, Caterina

    2016-08-01

    The role of nutrient loading on biomass growth in wastewater-impacted rivers is important in order to effectively optimize wastewater treatment to avoid excessive biomass growth in the receiving water body. This paper directly relates wastewater treatment plant (WWTP) effluent nutrients (including ammonia (NH3-N), nitrate (NO3-N) and total phosphorus (TP)) to the temporal and spatial distribution of epilithic algae and macrophyte biomass in an oligotrophic river. Annual macrophyte biomass, epilithic algae data and WWTP effluent nutrient data from 1980 to 2012 were statistically analysed. Because discharge can affect aquatic biomass growth, locally weighted scatterplot smoothing (LOWESS) was used to remove the influence of river discharge from the aquatic biomass (macrophytes and algae) data before further analysis was conducted. The results from LOWESS indicated that aquatic biomass did not increase beyond site-specific threshold discharge values in the river. The LOWESS-estimated biomass residuals showed a variable response to different nutrients. Macrophyte biomass residuals showed a decreasing trend concurrent with enhanced nutrient removal at the WWTP and decreased effluent P loading, whereas epilithic algae biomass residuals showed greater response to enhanced N removal. Correlation analysis between effluent nutrient concentrations and the biomass residuals (both epilithic algae and macrophytes) suggested that aquatic biomass is nitrogen limited, especially by NH3-N, at most sampling sites. The response of aquatic biomass residuals to effluent nutrient concentrations did not change with increasing distance to the WWTP but was different for P and N, allowing for additional conclusions about nutrient limitation in specific river reaches. The data further showed that the mixing process between the effluent and the river has an influence on the spatial distribution of biomass growth.

  10. Biomass production and nitrogen and phosphorus removal by the green alga Neochloris oleoabundans in simulated wastewater and secondary municipal wastewater effluent.

    Science.gov (United States)

    Wang, Bei; Lan, Christopher Q

    2011-05-01

    Biomass productivity of 350 mg DCW L(-1)day(-1) with a final biomass concentration of 3.15 g DCW L(-1) was obtained with Neochloris oleoabundans grown in artificial wastewater at sodium nitrate and phosphate concentrations of 140 and 47 mg L(-1), respectively, with undetectable levels of residual N and P in effluents. In secondary municipal wastewater effluents enriched with 70 mg N L(-1), the alga achieved a final biomass concentration of 2.1 g DCW L(-1) and a biomass productivity of 233.3 mg DCW L(-1)day(-1). While N removal was very sensitive to N:P ratio, P removal was independent of N:P ratio in the tested range. These results indicate that N. oleoabundans could potentially be employed for combined biofuel production and wastewater treatment.

  11. Prediction of phycoremediation of As(III) and As(V) from synthetic wastewater by Chlorella pyrenoidosa using artificial neural network

    Science.gov (United States)

    Podder, M. S.; Majumder, C. B.

    2017-03-01

    An artificial neural network (ANN) model was developed to predict the phycoremediation efficiency of Chlorella pyrenoidosa for the removal of both As(III) and As(V) from synthetic wastewater based on 49 data-sets obtained from experimental study and increased the data using CSCF technique. The data were divided into training (60%) validation (20%) and testing (20%) sets. The data collected was used for training a three-layer feed-forward back propagation (BP) learning algorithm having 4-5-1 architecture. The model used tangent sigmoid transfer function at input to hidden layer (tansing) while a linear transfer function (purelin) was used at output layer. Comparison between experimental results and model results gave a high correlation coefficient (R{allANN/2} equal to 0.99987 for both ions and exhibited that the model was able to predict the phycoremediation of As(III) and As(V) from wastewater. Experimental parameters influencing phycoremediation process like pH, inoculum size, contact time and initial arsenic concentration [either As(III) or As(V)] were investigated. A contact time of 168 h was mainly required for achieving equilibrium at pH 9.0 with an inoculum size of 10% (v/v). At optimum conditions, metal ion uptake enhanced with increasing initial metal ion concentration.

  12. Effects of L-Carnitine Supplements on Population Growth and Biochemical Composition in Micro-algae, Chlorella vulgaris%L-肉碱对普通小球藻Chlorella vulgaris种群增长和生化组成的影响

    Institute of Scientific and Technical Information of China (English)

    宋丹; 孙宇; 蔺丽丽; 陈玉珂; 董婧; 陈颖; 余涛; 张东鸣

    2011-01-01

    分别以0,5,50 mg/L的L-内碱(L-carnitine)处理淡水普通小球藻(Chlorella vulgaris),以SE为培养液,培养7 d,探究L-肉碱对淡水普通小球藻种群增长、总脂和可溶性蛋白质含量的影响.结果表明:不同质量浓度的L-肉碱在不同培养时期对普通小球藻种群增长影响显著(P<0.05);高浓度L-肉碱显著降低总脂含量(P<0.05),并使可溶性蛋白质含量显著升高(P<0.05).结果提示,在培养液中添加外源L-肉碱可能通过直接作用于普通小球藻,或促进培养液中微小生物分泌活性物质间接影响普通小球藻的种群增长及总脂和可溶性蛋白质的含量.%The study was conducted to investigate the effects of L-carnitine supplements on population growth, total lipids and soluble protein in freshwater micro-algae Chlorella vulgaris. Algae were cultured with SE formulations and enriched by 3 levels of L-carnitine: 0, 5 and 50 mg/L for 7 days. The results showed that L-camitine supplements significantly ( P < 0.05) affected the population growth of enriched algae and two levels of L-camitine enrichment (5, 50 mg/L) produced different responses on population growth compared with the control during culture period. Total lipids content was significantly ( P < 0.05) lower and soluble protein content was significantly ( P < 0.05) higher in 50 mg/L L-camitine enriched group than that in the other 2 groups. The results suggest that L-camitine enrichment might affect population growth and biochemical composition in freshwater micro-algae Chlorella vulgaris in a direct or indirect way.

  13. Effective and selective recovery of gold and palladium ions from metal wastewater using a sulfothermophilic red alga, Galdieria sulphuraria.

    Science.gov (United States)

    Ju, Xiaohui; Igarashi, Kensuke; Miyashita, Shin-Ichi; Mitsuhashi, Hiroaki; Inagaki, Kazumi; Fujii, Shin-Ichiro; Sawada, Hitomi; Kuwabara, Tomohiko; Minoda, Ayumi

    2016-07-01

    The demand for precious metals has increased in recent years. However, low concentrations of precious metals dissolved in wastewater are yet to be recovered because of high operation costs and technical problems. The unicellular red alga, Galdieria sulphuraria, efficiently absorbs precious metals through biosorption. In this study, over 90% of gold and palladium could be selectively recovered from aqua regia-based metal wastewater by using G. sulphuraria. These metals were eluted from the cells into ammonium solutions containing 0.2M ammonium salts without other contaminating metals. The use of G. sulphuraria is an eco-friendly and cost-effective way of recovering low concentrations of gold and palladium discarded in metal wastewater. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Biology and Industrial Applications of Chlorella: Advances and Prospects.

    Science.gov (United States)

    Liu, Jin; Chen, Feng

    2016-01-01

    Chlorella represents a group of eukaryotic green microalgae that has been receiving increasing scientific and commercial interest. It possesses high photosynthetic ability and is capable of growing robustly under mixotrophic and heterotrophic conditions as well. Chlorella has long been considered as a source of protein and is now industrially produced for human food and animal feed. Chlorella is also rich in oil, an ideal feedstock for biofuels. The exploration of biofuel production by Chlorella is underway. Chlorella has the ability to fix carbon dioxide efficiently and to remove nutrients of nitrogen and phosphorous, making it a good candidate for greenhouse gas biomitigation and wastewater bioremediation. In addition, Chlorella shows potential as an alternative expression host for recombinant protein production, though challenges remain to be addressed. Currently, omics analyses of certain Chlorella strains are being performed, which will help to unravel the biological implications of Chlorella and facilitate the future exploration of industrial applications.

  15. Advanced treatment of effluent from a wastewater treatment plant by embedded immobilized bacteria and algae system%固定化菌藻系统对污水处理厂出水的深度处理

    Institute of Scientific and Technical Information of China (English)

    严清; 高旭; 彭绪亚

    2012-01-01

    将海藻酸钠固定化活性污泥和小球藻制成颗粒小球,以自制的流化床反应器对重庆市某污水处理厂出水进行深度处理,探讨了系统对氨氮、TP、COD的去除效果,实验结果表明:在HRT=12 h,溶解氧浓度为3.0 mg/L左右,pH值为6.2至8.0之间,环境室温条件下,系统对氨氮、TP、COD均有较好的去除效果,系统稳定运行后对氨氮、TP、COD去除率基本维持在60%、60%和30%以上,出水氨氮、TP、COD浓度基本维持在8、0.5和40 mg/L以下,出水浓度达到了《城镇污水处理厂污染物排放标准》(GB 18918-2002)的一级A标准。这项研究显示固定化菌藻胶球系统在污水处理厂出水的深度处理中具有潜在的应用前景。%Coimmobilized activated sludge and Chlorella vulgaris with sodium alginate as entrapping agent were made into beads to treat effluent from a wastewater treatment plant in the fluidized bed reactor and the removal efficiencies of ammonia nitrogen,TP and COD were studied.The experiment indicates that under the conditions of natural temperature,HRT,DO,pH were 12 hours,3 mg/L,6.2 to 8.0,respectively,the embedded immobilized bacteria-algae has strong ability to remove ammonia nitrogen,TP and COD,and the removal rates are more than 60%,60% and 30%,respectively.The effluent concentrations of ammonia nitrogen,TP and COD basically maintain less than 8,0.5 and 40 mg/L,respectively,meeting the first level A criteria specified in the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant(GB18918-2002).This study shows that coimmobilization of activated sludge and Chlorella vulgaris in small beads has the potential application prospect in the advanced treatment of effluent from wastewater treatment plants.

  16. Simultaneous removal of inorganic and organic compounds in wastewater by freshwater green microalgae.

    Science.gov (United States)

    Zhou, Guang-Jie; Ying, Guang-Guo; Liu, Shan; Zhou, Li-Jun; Chen, Zhi-Feng; Peng, Fu-Qiang

    2014-08-01

    Batch experiments were carried out for 7 days to investigate the simultaneous removal of various organic and inorganic contaminants including total nitrogen (TN), total phosphorus (TP), metals, pharmaceuticals and personal care products (PPCPs), endocrine disrupting chemicals (EDCs), and estrogenic activity in wastewater by four freshwater green microalgae species, Chlamydomonas reinhardtii, Scenedesmus obliquus, Chlorella pyrenoidosa and Chlorella vulgaris. After treatment for 7 days, 76.7-92.3% of TN, and 67.5-82.2% of TP were removed by these four algae species. The removal of metals from wastewater by the four algae species varied among the metal species. These four algae species could remove most of the metals efficiently (>40% removal), but showed low efficiencies in removing Pb, Ni and Co. The four algae species were also found to be efficient in removing most of the selected organic compounds with >50% removal, and the estrogenic activity with removal efficiencies ranging from 46.2 to 81.1% from the wastewater. Therefore, algae could be harnessed to simultaneously remove various contaminants in wastewater.

  17. Enzymatic pretreatment of Chlorella vulgaris for biogas production: Influence of urban wastewater as a sole nutrient source on macromolecular profile and biocatalyst efficiency.

    Science.gov (United States)

    Mahdy, Ahmed; Ballesteros, Mercedes; González-Fernández, Cristina

    2016-01-01

    Two biocatalysts, namely carbohydrases and proteases, were assessed for organic matter solubilisation and methane yield enhancement of microalgae biomass. This study evidenced Chlorella vulgaris carbohydrate accumulation (40% on VSS basis) when grown in urban wastewater. Despite of the carbohydrate prevailing fraction, protease pretreatment showed higher organic matter hydrolysis efficiency (54%). Microscopic observation revealed that carbohydrases affected slightly the cell wall while protease was not selective to wall constituents. Raw and pretreated biomass was digested at 1.5 kg tCOD m(-3) day(-1) organic loading rate (OLR1) and 20 days hydraulic retention time (HRT). The highest methane yield (137 mL CH4 g COD in(-1)) was achieved in the reactor fed with protease pretreated C. vulgaris. Additionally, anaerobic digestion was conducted at OLR2 (3 kg tCOD m(-3) day(-1)) and HRT (15 days). When compared to raw biomass, methane yield increased 5- and 6.3-fold at OLR1 and OLR2, respectively. No inhibitors were detected during the anaerobic digestion.

  18. Simultaneous Wastewater Treatment, Algal Biomass Production and Electricity Generation in Clayware Microbial Carbon Capture Cells.

    Science.gov (United States)

    Jadhav, Dipak A; Jain, Sumat C; Ghangrekar, Makarand M

    2017-05-02

    Performance of microbial carbon capture cells (MCCs), having a low-cost clayware separator, was evaluated in terms of wastewater treatment and electricity generation using algae Chlorella pyrenoidosa in MCC-1 and Anabaena ambigua in MCC-2 and without algae in a cathodic chamber of MCC-3. Higher power production was achieved in MCC-1 (6.4 W/m(3)) compared to MCC-2 (4.29 W/m(3)) and MCC-3 (3.29 W/m(3)). Higher coulombic efficiency (15.23 ± 1.30%) and biomass production (66.4 ± 4.7 mg/(L*day)) in MCC-1 indicated the superiority of Chlorella over Anabaena algae for carbon capture and oxygen production to facilitate the cathodic reduction. Algal biofilm formation on the cathode surface of MCC-1 increased dissolved oxygen in the catholyte and decreased the cathodic charge transfer resistance with increase in reduction current. Electrochemical analyses revealed slow cathodic reactions and increase in internal resistance in MCC-2 (55 Ω) than MCC-1 (30 Ω), due to lower oxygen produced by Anabaena algae. Thus, biomass production in conjunction with wastewater treatment, CO2 sequestration and electricity generation can be achieved using Chlorella algal biocathode in MCC.

  19. Nutrient removal from horticultural wastewater by benthic filamentous algae Klebsormidium sp., Stigeoclonium spp. and their communities: From laboratory flask to outdoor Algal Turf Scrubber (ATS).

    Science.gov (United States)

    Liu, Junzhuo; Danneels, Bram; Vanormelingen, Pieter; Vyverman, Wim

    2016-04-01

    Benthic filamentous algae have evident advantages in wastewater treatment over unicellular microalgae, including the ease in harvesting and resistance to predation. To assess the potentials of benthic filamentous algae in treating horticultural wastewater under natural conditions in Belgium, three strains and their mixture with naturally wastewater-borne microalgae were cultivated in 250 ml Erlenmeyer flasks in laboratory as well as in 1 m(2) scale outdoor Algal Turf Scrubber (ATS) with different flow rates. Stigeoclonium competed well with the natural wastewater-borne microalgae and contributed to most of the biomass production both in Erlenmeyer flasks and outdoor ATS at flow rates of 2-6 L min(-1) (water velocity 3-9 cm s(-1)), while Klebsormidium was not suitable for growing in horticultural wastewater under the tested conditions. Flow rate had great effects on biomass production and nitrogen removal, while phosphorus removal was less influenced by flow rate due to other mechanisms than assimilation by algae. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. CO2 Biofixation by the Cyanobacterium Spirulina sp. LEB 18 and the Green Alga Chlorella fusca LEB 111 Grown Using Gas Effluents and Solid Residues of Thermoelectric Origin.

    Science.gov (United States)

    da Silva Vaz, Bruna; Costa, Jorge Alberto Vieira; de Morais, Michele Greque

    2016-01-01

    The concentration of carbon dioxide (CO2) in the atmosphere has increased from 280 to 400 ppm in the last 10 years, and the coal-fired power plants are responsible for approximately 22 % of these emissions. The burning of fossil fuel also produces a great amount of solid waste that causes serious industrial and environmental problems. The biological processes become interesting alternative in combating pollution and developing new products. The objective of this study was to evaluate the CO2 biofixation potential of microalgae that were grown using gaseous effluents and solid residues of thermoelectric origin. The microalgae Chlorella fusca LEB 111 presented higher rate of CO2 biofixation (42.8 %) (p Spirulina sp. LEB 18. The values for the CO2 biofixation rates and the kinetic parameters of Spirulina and Chlorella cells grown using combustion gas did not differ significantly from those of cells grown using CO2 and a carbon source in the culture media. These microalgae could be grown using ash derived from coal combustion, using the minerals present in this residue as the source of the essential metals required for their growth and the CO2 derived from the combustion gas as their carbon source.

  1. 小球藻(Chlorella zofingiensis)生物合成虾青素的应用前景%Prospects for astaxanthin production of the green alga Chlorella zofingiensis

    Institute of Scientific and Technical Information of China (English)

    王艳; 黄俊潮; 陈峰

    2007-01-01

    虾青素是一种具有超强抗氧化特性的酮式类胡萝卜素,在食品和医药领域有着极广阔的应用前景.小球藻 (Chlorella zofingiensis) 的虾青素合成能力被报道后,倍受国内外学者关注.本文综述了近年来国内外在C.zofingiensis虾青素生物合成方面的研究进展,包括虾青素合成有关的诱导条件、虾青素合成过程中的生理变化、虾青素合成途径以及合成酶表达的分子调控等方面,并对小球藻C.zofingiensis的产业化前景进行了展望.

  2. Development of technology for organic wastewater treatment by microorganisms and production of materials for conserving environment. Part 1. ; Organic wastewater treatment by photoshynthetic bacteria and microalgae. Biseibutsu ni yoru yukikei haisui shori to yojo biseibutsu no shigenka ni kansuru kenkyu. 1. ; Kogosei saikin to sorui ni yoru haisui shori ni kansuru kihonteki kento

    Energy Technology Data Exchange (ETDEWEB)

    Kato, A.; Kita, D.; Kubotera, T.; Tsuji, H. (Obayashi Corp., Tokyo (Japan))

    1994-02-10

    The present report introduces a system which simultaneously executes the purification of organic wastewater and recovery of recyclable matters. The system uses photosynthetic bacteria and microalgae as well as the conventionally used activated sludge bacteria. Environmental maintenance use agents are produced by processing bacteria and algae generated during the wastewater treatment. The photosynthetic bacteria are purple non-sulfuric bacteria, which also contain amino acid, vitamin and other useful physiologically activated matter. The wastewater treatment which utilizes them has the advantage of miniaturizing the plant and lowering the power. As algae, chlorella and spirulina are used in order to remove the nitrogen and phosphorus in the water to be treated. The following is an actual result of wastewater treatment in a beancurd maker's plant: if purple non-sulfuric bacteria are used, high concentration organic wastewater can be treated without dilution so that the plant can be miniaturized. The chlorella culture is so effective that the nitrogen and phosphorus remaining in the wastewater are absorbed and removed by the chlorella with its increasing. 9 refs., 13 figs., 2 tabs.

  3. Light attenuation on Chlorella vulgaris cells

    Science.gov (United States)

    Krol, Tadeusz; Lotocka, Maria

    1993-12-01

    The laboratory measurements of spectrum of light attenuation on phytoplankton particles i.e. monoculture of unicellural green algae Chlorella vulgaris are presented. The measurements were carried out for alive culture and the cultures subjected to chemical (NaOH) or physical (ultrasounds) modification. The distinct changes in the light attenuation spectrum were a result of modification of the internal cell structures.

  4. Substitution of stable isotopes in Chlorella

    Science.gov (United States)

    Flaumenhaft, E.; Katz, J. J.; Uphaus, R. A.

    1969-01-01

    Replacement of biologically important isotopes in the alga Chlorella by corresponding heavier stable isotopes produces increasingly greater deviations from the normal cell size and changes the quality and distribution of certain cellular components. The usefulness of isotopically altered organisms increases interest in the study of such permuted organisms.

  5. Bioremediation of wastewater using microalgae

    Science.gov (United States)

    Chalivendra, Saikumar

    Population expansion and industrial development has deteriorated the quality of freshwater reservoirs around the world and has caused freshwater shortages in certain areas. Discharge of industrial effluents containing toxic heavy metals such as Cd and Cr into the environment have serious impact on human, animal and aquatic life. In order to solve these problems, the present study was focused on evaluating and demonstrating potential of microalgae for bioremediation of wastewater laden with nitrogen (N) in the form of nitrates, phosphorous (P) in the form of phosphates, chromium (Cr (VI)) and cadmium (Cd (II)). After screening several microalgae, Chlorella vulgaris and algae taken from Pleasant Hill Lake were chosen as candidate species for this study. The viability of the process was demonstrated in laboratory bioreactors and various experimental parameters such as contact time, initial metal concentration, algae concentration, pH and temperature that would affect remediation rates were studied. Based on the experimental results, correlations were developed to enable customizing and designing a commercial Algae based Wastewater Treatment System (AWTS). A commercial AWTS system that can be easily customized and is suitable for integration into existing wastewater treatment facilities was developed, and capital cost estimates for system including installation and annual operating costs were determined. The work concludes that algal bioremediation is a viable alternate technology for treating wastewater in an economical and sustainable way when compared to conventional treatment processes. The annual wastewater treatment cost to remove N,P is ~26x lower and to remove Cr, Cd is 7x lower than conventional treatment processes. The cost benefit analysis performed shows that if this technology is implemented at industrial complexes, Air Force freight and other Department of Defense installations with wastewater treatment plants, it could lead to millions of dollars in

  6. Multivariate statistical analysis of water chemistry conditions in three wastewater stabilization ponds with algae blooms and pH fluctuations.

    Science.gov (United States)

    Wallace, Jack; Champagne, Pascale; Hall, Geof

    2016-06-01

    The wastewater stabilization ponds (WSPs) at a wastewater treatment facility in eastern Ontario, Canada, have experienced excessive algae growth and high pH levels in the summer months. A full range of parameters were sampled from the system and the chemical dynamics in the three WSPs were assessed through multivariate statistical analysis. The study presents a novel approach for exploratory analysis of a comprehensive water chemistry dataset, incorporating principal components analysis (PCA) and principal components (PC) and partial least squares (PLS) regressions. The analyses showed strong correlations between chl-a and sunlight, temperature, organic matter, and nutrients, and weak and negative correlations between chl-a and pH and chl-a and DO. PCA reduced the data from 19 to 8 variables, with a good fit to the original data matrix (similarity measure of 0.73). Multivariate regressions to model system pH in terms of these key parameters were performed on the reduced variable set and the PCs generated, for which strong fits (R(2) > 0.79 with all data) were observed. The methodologies presented in this study are applicable to a wide range of natural and engineered systems where a large number of water chemistry parameters are monitored resulting in the generation of large data sets. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Effect of algal food (Chlorella vulgaris concentration and inoculation density on the competition among three planktonic Brachionidae (Rotifera: Monogononta Efecto de la concentración de algas (Chlorella vulgaris y la densidad de inoculación sobre la competencia entre tres Brachionidae (Rotifera: Monogononta planctónicos

    Directory of Open Access Journals (Sweden)

    S.S.S. Sarma

    2008-08-01

    Full Text Available Competitive outcomes among three rotifer species (Anuraeopsis fissa, Brachionus havanaensis and B. angularis were quantified with different inoculation densities of two competing species at a time (0, 25, 50, 75 and 100% and using different algal (Chlorella vulgaris densities (0.2 x 10(6, 0.4 x 10(6 and 0.8 x 10(6 cells ml-1. In control cultures, when each species was grown alone, the population growth of rotifers increased with increasing food availability in the medium, but in mixed cultures, decreased with increasing proportion of the competing species. At low food level, compared to B. havanaensis, B. angularis had stronger negative impact on A. fissa. However, with increasing algal density, both species of Brachionus had similar but reduced impact on A. fissa. Population growth of B. havanaensis was more adversely affected by A. fissa than B. angularis at low and intermediate concentrations. At high food level, the impact of either A. fissa or B. angularis on the growth of B. havanaensis was similar. When grown alone, for a given food density, A. fissa was more numerically (4 to 6 times abundant than the other two species. The rate of population increase (r of rotifers increased with increasing food levels. Depending on the rotifer species and the test conditions, the r varied from -0.001 to 0.34 d-1. Results showed that the competitive outcome in the tested rotifers depended on the initial inoculation density of the competing species, the offered food concentration as well as the interaction of these two factors.Se evaluaron los resultados de la competencia entre tres especies de rotíferos (Anuraeopsis fissa, Brachionus havanaensis y B. angularis usando dos especies a la vez con diferentes densidades de inóculo (0, 25, 50, 75 y 100% y diferentes niveles de alga (Chlorella vulgaris; 0.2 x 10(6, 0.4 x 10(6 y 0.8 x 10(6 células ml-1. En cultivos monoespecíficos, utilizados como control, el crecimiento poblacional de rotíferos aument

  8. Effect of Bensulfuron-Methyl on Growth of Chlorella pyrenoidosa

    Institute of Scientific and Technical Information of China (English)

    YUE Xia-li; YU Xiao-qing; LIU Yong-hong; DONG Yuan-yan

    2007-01-01

    To study the growth effects of differing concentrations of bensulfuron-methyl on Chlorella pyrenoidosa and to evaluate the ecological risk, the effects of bensulfuron-methyl on the growth and the content change of chlorophyll and protein in Chlorella pyrenoidosa were studied through 96 h acute toxicity tests. Bensulfuron-methyl accelerated the growth of algae at lower concentrations (< 1 mg L-1) with content increase of chlorophyll or protein, and it inhibited the growth of algae at higher concentrations (>5 mg L-1). The content of chlorophyll or protein in algae cells reduced with the increasing concentration of bensulfuron-methyl, exhibiting the good concentration-effect relationship. The 96 h-EC50 of bensulfuronmethyl upon the algae was 15.7 mg L-1. Bensulfuron-methyl has inhibiting effect on the growth of Chlorella pyrenoidosa and is low in toxicity.

  9. Alternative Respiration Induced by Glucose Stimulation and Variation of Adenylate Energy Charge in Glucose-Starved Cells of Green Alga Chlorella Protothecoides

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Effects of inhibitors and glucose on cytochrome and alternative respiration and on adenylate energy charge (AEC) in glucose-starved Chlorella protothecoides were investigated. 1 mmol/L azide (NaN3), which immediately caused an increase of O2 uptake by inhibiting the cytochrome pathway and stimulating alternative respiration, resulted in a decrease of AEC value from 0. 83 to 0. 34 within 3 minutes. When 1 mmol/L salicylhydroxamic acid (SHAM) was added into the cell suspension, there was no apparent variation in AEC. Adding NaN3 and SHAM together into cell suspension to inhibit both cytochrome and alternative pathways showed a same change of AEC as that of adding NaN3 alone. When 2.0 mmol/L of glucose was added to a suspension of glucose-starved cells, the O2 uptake rate was immediately stimulated from 0.81 up to 1.34 [μrnol/L O2 · min-] · (mL PCV)-1]. The respiration stimulated by glucose could be inhibited about 20% by adding 1 mmol/L SHAM. It was found by titration with SHAM in the absence and presence of NaN3 that 53% of O2 uptake went through the cytochrome pathway and 45% of the alternate pathway was operational in enhanced respiration. It implied that induced operation of the alternative respiratory pathway probably resulted from the burst of the electron flux into the electron transport chain by glucose stimulation.

  10. Metagenomic analysis of microbiota structure evolution in phytoremediation of a swine lagoon wastewater.

    Science.gov (United States)

    Ye, Jianfeng; Song, Zhaofeng; Wang, Liang; Zhu, Jun

    2016-11-01

    Pytoremediation was studied in this project to treat swine manure lagoon wastewater characteristic of high concentrations of organic carbon, ammonium (N) and phosphorus (P). The impacts of introducing exogenous microalgae Chlorella into the lagoon wastewater on the removal of major nutrients and the transformation of the native wastewater microbiota structure were explored under two phytoremediation modes (shake flask and CO2-air bubbling). The results showed that the inoculation of microalgae could significantly enhance N and P removal. Metagenomic analysis of the native microbiota composition in the wastewater affected by algae inoculation revealed that a substantial population of algicidal bacteria was developed in the shake flask system, while in the CO2-air bubbling system, a niche for more mutualistic bacteria was created, which benefited the maximal algal growth with the simultaneous optimal N and P removal. To our knowledge, this study presents, the first reported case of applying metagenomic approach to a phytoremediation system treating real swine lagoon wastewater.

  11. Algae Resources

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-06-01

    Algae are highly efficient at producing biomass, and they can be found all over the planet. Many use sunlight and nutrients to create biomass, which contain key components—including lipids, proteins, and carbohydrates— that can be converted and upgraded to a variety of biofuels and products. A functional algal biofuels production system requires resources such as suitable land and climate, sustainable management of water resources, a supplemental carbon dioxide (CO2) supply, and other nutrients (e.g., nitrogen and phosphorus). Algae can be an attractive feedstock for many locations in the United States because their diversity allows for highpotential biomass yields in a variety of climates and environments. Depending on the strain, algae can grow by using fresh, saline, or brackish water from surface water sources, groundwater, or seawater. Additionally, they can grow in water from second-use sources such as treated industrial wastewater; municipal, agricultural, or aquaculture wastewater; or produced water generated from oil and gas drilling operations.

  12. Inhibition of nitrification in municipal wastewater-treating photobioreactors: Effect on algal growth and nutrient uptake.

    Science.gov (United States)

    Krustok, I; Odlare, M; Truu, J; Nehrenheim, E

    2016-02-01

    The effect of inhibiting nitrification on algal growth and nutrient uptake was studied in photobioreactors treating municipal wastewater. As previous studies have indicated that algae prefer certain nitrogen species to others, and because nitrifying bacteria are inhibited by microalgae, it is important to shed more light on these interactions. In this study allylthiourea (ATU) was used to inhibit nitrification in wastewater-treating photobioreactors. The nitrification-inhibited reactors were compared to control reactors with no ATU added. Microalgae had higher growth in the inhibited reactors, resulting in a higher chlorophyll a concentration. The species mix also differed, with Chlorella and Scenedesmus being the dominant genera in the control reactors and Cryptomonas and Chlorella dominating in the inhibited reactors. The nitrogen speciation in the reactors after 8 days incubation was also different in the two setups, with N existing mostly as NH4-N in the inhibited reactors and as NO3-N in the control reactors.

  13. Study on the Enhancement of Immobilized Chlorella Balls' Performance%固定化藻球的强化研究

    Institute of Scientific and Technical Information of China (English)

    严清; 冯国忠

    2011-01-01

    To solve the problems that chlorella balls loose their integrity and algae cells leach easily in the wastewater with phosphate, 1% of activated carbon was added into the balls and then hardened by marinating in CaCl2 solution. The results showed that adding activated carbon could improve the performance of immobilized chlorella balls, and the optimal adding amount of activated carbon was 1 percent of alginate sodium. Hardening could enhance the ability of immobilized chlorella balls in removing NH4+-N and PO43--P from waste water and improve the density of chlorella in ball. The removal efficiency of hardened chlorella balls of NH4+-N and PO43-P were above 80% and 96% respectively.%为解决褐藻胶球在含磷污水中结构易疏松、小球藻易泄漏及胶球易破碎的问题,进行了添加质量分数为1%的活性炭和CaCl2溶液浸泡固定化藻球的加固强化的试验.结果表明,采用添加活性炭的方法可以很好地改进固定化小球的性能,其最佳的添加量为海藻酸钠凝胶的1%;加固胶球系统对氨氮(NH4+-N)的去除率持续增加,最高可增至80%左右;对正磷酸盐(PO43--P)也有较好地去除效果,去除率可达96%以上:胶球经过加固后,胶球内藻细胞密度得到较大提高,固定化性能得到改善.

  14. Application of algae-biosensor for environmental monitoring.

    Science.gov (United States)

    Umar, Lazuardi; Alexander, Frank A; Wiest, Joachim

    2015-01-01

    Environmental problems including water and air pollution, over fertilization, insufficient wastewater treatment and even ecological disaster are receiving greater attention in the technical and scientific area. In this paper, a method for water quality monitoring using living green algae (Chlorella Kessleri) with the help of the intelligent mobile lab (IMOLA) is presented. This measurement used two IMOLA systems for measurement and reference simultaneously to verify changes due to pollution inside the measurement system. The IMOLA includes light emitting diodes to stimulate photosynthesis of the living algae immobilized on a biochip containing a dissolved oxygen microsensor. A fluid system is used to transport algae culture medium in a stop and go mode; 600s ON, 300s OFF, while the oxygen concentration of the water probe is measured. When the pump stops, the increase in dissolved oxygen concentration due to photosynthesis is detected. In case of a pollutant being transported toward the algae, this can be detected by monitoring the photosynthetic activity. Monitoring pollution is shown by adding emulsion of 0,5mL of Indonesian crude palm oil and 10mL algae medium to the water probe in the biosensor.

  15. Evaluation of High Rate Algae Ponds for treatment of anaerobically digested wastewater: Effect of CO2 addition and modification of dilution rate.

    Science.gov (United States)

    de Godos, I; Arbib, Z; Lara, E; Rogalla, F

    2016-11-01

    High Rate Algae Ponds (HRAP) are the simplest way to grow microalgae biomass and an interesting alternative for wastewater treatment. In this work the performance of these systems was evaluated using anaerobically digested wastewater as culture medium. Two variables were studied in long-term mode: the carbon dioxide supply and the modification of the dilution rates. The results showed that CO2 supply increases the productivity but less than expected considering the potential biomass generation calculated based on the ratios of carbon to nitrogen of microalgae and wastewater. The assimilation into biomass only accounted for 57% of the inlet nitrogen under the best conditions because nitrification and volatilization reduced the availability of this element. The operation under short hydraulic retention times presented a more interesting performance with higher biomass productivities. The biomass produced was efficiently harvested with in a Dissolved Air Flotation (DAF) unit. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Evaluation of the Marine Algae Gracilaria and its Activated Carbon for the Adsorption of Ni(II from Wastewater

    Directory of Open Access Journals (Sweden)

    A. Esmaeili

    2011-01-01

    Full Text Available The batch removal of Ni2+ from aqueous solution and wastewater using marine dried (MD red algae Gracilaria and its activated carbon (AC was studied. For these experiments, adsorption of Ni2+ was used to form two biomasses of AC and MD. Both methods used different pH values, biomass and initial concentration of Ni2+. Subsequently adsorption models and kinetic studies were carried out. The maximum efficiencies of Ni2+ removal were 83.55% and 99.04% for MD and AC respectively developed from it. The experimental adsorption data were fitted to the Langmuir adsorption model. The nickel(II uptake by the biosorbents was best described by pseudo-second order rate model. The kinetic studies showed that the heavy metal uptake was observed more rapidly by the AC with compared to MD. AC method developed from MD biomass exhibited higher biosorption capacity. Adsorption capacity is related to the pH of solution, pH 5.0 is optimal for nickel. The maximum efficiencies of Ni2+ removal were for AC method. The capacity is related to the pH of solution, pH 5.0 is optimal for nickel. The equilibrium adsorption data are correlated by Langmuir isotherm equation. The adsorption kinetic data can be described by the second order kinetic models

  17. Effects of Nutritional Conditions on the Growth and Energy Efficiency of Chlorella Vulgaris in the Wastewater%营养条件对污水中小球藻生长及产能效应的影响

    Institute of Scientific and Technical Information of China (English)

    马剑敏; 苏秀燕; 马顷; 王程丽; 董文静; 靳同霞; 马帅

    2012-01-01

    以过滤的富营养化的鱼塘废水为培养液,添加外源的碳、氮、磷元素,考察污水中不同的外源无机碳浓度、总氮浓度、总磷浓度对小球藻(Chlorella vulgaris)的生长、油脂含量和烃类含量的影响.在25℃、光照强度为4500 Lux、光暗比为12L:12D的条件下培养10d.单因子方差分析和多重比较结果表明:(1)以Na2CO3做碳源,小球藻生物量和烃类含量在外源无机碳浓度为6 mg/L时最高,油脂含量在外源无机碳浓度为12 mg/L最高.(2)以KNO3做氮源,小球藻生物量在总氮浓度为25 mg/L时最高,油脂含量在总氮浓度为15 mg/L时最高,烃含量在总氮浓度为20 mg/L时最高.(3)以KH2PO4做磷源,小球藻生物量和烃类含量在总磷浓度为2 mg/L时最高,油脂含量在总磷浓度为15 mg/L时最高.%With eutrophication wastewater of ponds filtered as culture medium, adding carbon source, nitrogen source and phosphorus source, the influences of different concentrations of inorganic carbon, total nitrogen and total phosphorus of wastewater on biomass, lipid content and hydrocarbon content of Chlorella vulgaris were studied. The culture had grown at the temperature of 25 ℃, the light intensity of 4,500 Lux, the photoperiod of 12L : 12D for ten days. The results of one way anova and multiple comparison showed that with Na2CO3, as carbon source, biomass and hydrocarbon content of Chlorella vulgaris were the highest at the inorganic carbon concentration of 6 mg/L when the highest lipid content was at the inorganic carbon concentration of 12 mg/L. With KNO3 as nitrogen source, the biomass of Chlorella vulgaris was the highest at the total nitrogen concentration of 25 mg/L; the highest lipid content was at the total nitrogen concentration of 15 mg/L; the highest hydrocarbon content was at the total nitrogen concentration of 20 mg/L. With KH2PO4 as phosphorus source, biomass and hydrocarbon content of Chlorella vulgaris were the highest at the total phosphate

  18. Chemical characterization and anaerobic biodegradability of hydrothermal liquefaction aqueous products from mixed-culture wastewater algae.

    Science.gov (United States)

    Tommaso, Giovana; Chen, Wan-Ting; Li, Peng; Schideman, Lance; Zhang, Yuanhui

    2015-02-01

    This study examined the chemical characteristics and the anaerobic degradability of the aqueous product from hydrothermal liquefaction (HTL-ap) from the conversion of mixed-culture algal biomass grown in a wastewater treatment system. The effects of the HTL reaction times from 0 to 1.5 h, and reaction temperatures from 260 °C to 320 °C on the anaerobic degradability of the HTL-ap were quantified using biomethane potential assays. Comparing chemical oxygen demand data for HTL-ap from different operating conditions, indicated that organic matter may partition from organic phase to aqueous phase at 320 °C. Moderate lag phase and the highest cumulative methane production were observed when HTL-ap was obtained at 320 °C. The longest lag phase and the smallest production rate were observed in the process fed with HTL-ap obtained at 300 °C. Nevertheless, after overcoming adaptation issues, this HTL-ap led to the second highest accumulated specific methane production. Acetogenesis was identified as a possible rate-limiting pathway.

  19. The long-term effects of wall attached microalgal biofilm on algae-based wastewater treatment.

    Science.gov (United States)

    Su, Yanyan; Mennerich, Artur; Urban, Brigitte

    2016-10-01

    The influence of the reactor wall attached biofilm on the nutrient removal performance was investigated in an open photobioreactor during long-term operation. Total nitrogen and phosphorus removal efficiencies were statistically similar between reactor with (reactor A) and without (reactor B) biofilm at the Hydraulic Retention Time (HRT) of 18, 13.5 and 9days. When the HRT reduced to 8days, total nitrogen and phosphorus removal efficiencies in the reactor A were 42.95±5.11% and 97.97±1.12%, respectively, while significant lower removal efficiencies (38.06±5.80% for total nitrogen and 83.14±8.16% for phosphorus) were obtained in the reactor B. The VSS concentrations throughout the test were statistically similar for the two reactors, with a mean value of 0.63±0.25g/l for reactor A and 0.69±0.20g/l for reactor B. This study indicated that the reactor wall attached biofilm supported high phosphorus and nitrogen removal, which may provide insight into the practical implementation of microalgae-based wastewater treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Removal of toxic chromium from aqueous solution, wastewater and saline water by marine red alga Pterocladia capillacea and its activated carbon

    Directory of Open Access Journals (Sweden)

    Ahmed El Nemr

    2015-01-01

    Full Text Available Pterocladia capillacea, a red marine macroalgae, was tested for its ability to remove toxic hexavalent chromium from aqueous solution. A new activated carbon obtained from P. capillacea via acid dehydration was also investigated as an adsorbent for toxic chromium. The experiments were conducted to study the effect of important parameters such as pH, chromium concentration and adsorbent weight. Batch equilibrium tests at different pH conditions showed that at pH 1.0, a maximum chromium uptake was observed for both inactivated dried red alga P. capillacea and its activated carbon. The maximum sorption capacities for dried red alga and its activated carbon were about 12 and 66 mgg−1, respectively, as calculated by Langmuir model. The ability of inactivated red alga P. capillacea and developed activated carbon to remove chromium from synthetic sea water, natural sea water and wastewater was investigated as well. Different isotherm models were used to analyze the experimental data and the models parameters were evaluated. This study showed that the activated carbon developed from red alga P. capillacea is a promising activated carbon for removal of toxic chromium.

  1. 利用啤酒废水小球藻异养培养%Heterotrophic Cultivation of Chlorella for Beer brewery wastewater treatment

    Institute of Scientific and Technical Information of China (English)

    曲春波; 史贤明

    2009-01-01

    [目的]利用小球藻异养培养技术处理啤酒废水,旨在为啤酒废水资源化利用和降低小球藻生产成本提供一条途径.[方法]在含有10 g/L葡萄糖的基本培养基进行异养小球藻高效藻株的筛选,并用于啤酒废水的资源化处理.[结果]从5株小球藻中得到2株适合高密度异养培养的藻株(Chlorella pyrenoidosa 15-2070和Chlorella vulgaris 15-2075),在啤酒废水的资源化处理过程中这2株小球藻得到非常接近的实验结果.利用由废水配制含10 g/L葡萄糖的基本培养液培养Chlorella pyrenoidosa 15-2070获得了5.3 g/L藻细胞;并且在此过程中,啤酒废水得到有效利用,几种主要污染物最高去除率为:CODcr,92.2%;BOD5,95.1%;NO3--N,98.5%;NH4+-N,92.3%.[结论]啤酒废水中的重要环境污染物在培养小球藻的过程中可以得到有效地清除,并从中可以获得具有商业价值的小球藻细胞.

  2. WASTEWATER

    African Journals Online (AJOL)

    acid in the ozonized wastewater were degraded completely by ... wastewater from pulp and paper plants pose serious environmental problems when they are ... support aquatic life (Stern & Gasner 1974), Gupta and Battacharya 1985).

  3. SUSTAINABLE PRODUCTION OF MICROALGAE OIL FEEDSTOCK USING MUNICIPAL WASTEWATER AND CO2 FERTILIZATION

    Directory of Open Access Journals (Sweden)

    Gina Chaput

    2012-07-01

    Full Text Available The increasing scarcity of fossil fuels has forced industry to look for new cost effective, clean,and sustainable sources of energy. With recent advances in technology, biofuels have become a more viableoption. Microalgae are cost effective and efficient feedstock for the production of biodiesel. One of the algae advantages is the ability to grow it in a wastewater media. This provides essential nutrients without the addition of chemicals. When grown in a photobioreactor, the algae can be cultivated on non-arable land, preventing competition with food supply unlike other leading biodiesel feedstocks such as canola and soybean crop. The strain of algae used in this study was Chlorella sp. The primary goals of this project were to determine the viability of algae growth in a wastewater medium, test the effectiveness of an alternate nitrogen source, andexamine the effects of CO2 fertilization on algae growth and lipid content. Sodium bicarbonate was used to simulate CO2 fertilization. Results showed that: the use of a 50/50 wastewater/reverse osmosis (RO medium yielded 83% of the lipid productivity of a 100% RO medium while the 100% wastewater medium yielded 35% of the lipid productivity; urea as a substitute for KNO3 in 100% RO, 50/50, and 100% Wastewater medium increased lipid productivity by 1.4%, 52.3%, and 88.3%, respectively. The lipid productivity of urea 100% wastewater medium was increased by 68.9% when fertilized with sodium bicarbonate. The optimum trial, a urea 100% wastewater medium with daily additions of sodium bicarbonate, had a lipid productivity of 0.062 grams/liter of growth medium and a volumetric biomass yield of 0.15 grams per liter-day.

  4. Effects of lead on growth, photosynthetic characteristics and production of reactive oxygen species of two freshwater green algae.

    Science.gov (United States)

    Dao, Ly H T; Beardall, John

    2016-03-01

    In the natural environment, heavy metal contamination can occur as long-term pollution of sites or as pulses of pollutants from wastewater disposal. In this study two freshwater green algae, Chlorella sp. FleB1 and Scenedesmus YaA6, were isolated from lead-polluted water samples and the effects of 24 h vs 4 and 8 d exposure of cultures to lead on growth, photosynthetic physiology and production of reactive oxygen species (ROS) of these algae were investigated. In Chlorella sp. FleB1, there was agreement between lead impacts on chlorophyll content, photosynthesis and growth in most case. However, in Scenedesmus acutus YaA6 growth was inhibited at lower lead concentrations (0.03-0.87 × 10(-9) M), under which ROS, measured by 2',7' dichlorodihydrofluorescein diacetate fluorescence, were 4.5 fold higher than in controls but photosynthesis was not affected, implying that ROS had played a role in the growth inhibition that did not involve direct effects on photosynthesis. Effects of short-term (5 h, 24 h) vs long-term (4 d and 8 d) exposure to lead were also compared between the two algae. The results contribute to our understanding of the mechanisms of lead toxicity to algae.

  5. Fuel from Wastewater - Harnessing a Potential Energy Source in Canada through the Co-location of Algae Biofuel Production to Sources of Effluent, Heat and CO2

    Science.gov (United States)

    Klise, G. T.; Roach, J. D.; Passell, H. D.; Moreland, B. D.; O'Leary, S. J.; Pienkos, P. T.; Whalen, J.

    2010-12-01

    Sandia National Laboratories is collaborating with the National Research Council (NRC) Canada and the National Renewable Energy Laboratory (NREL) to develop a decision-support model that will evaluate the tradeoffs associated with high-latitude algae biofuel production co-located with wastewater, CO2, and waste heat. This project helps Canada meet its goal of diversifying fuel sources with algae-based biofuels. The biofuel production will provide a wide range of benefits including wastewater treatment, CO2 reuse and reduction of demand for fossil-based fuels. The higher energy density in algae-based fuels gives them an advantage over crop-based biofuels as the “production” footprint required is much less, resulting in less water consumed and little, if any conversion of agricultural land from food to fuel production. Besides being a potential source for liquid fuel, algae have the potential to be used to generate electricity through the burning of dried biomass, or anaerobically digested to generate methane for electricity production. Co-locating algae production with waste streams may be crucial for making algae an economically valuable fuel source, and will certainly improve its overall ecological sustainability. The modeling process will address these questions, and others that are important to the use of water for energy production: What are the locations where all resources are co-located, and what volumes of algal biomass and oil can be produced there? In locations where co-location does not occur, what resources should be transported, and how far, while maintaining economic viability? This work is being funded through the U.S. Department of Energy (DOE) Biomass Program Office of Energy Efficiency and Renewable Energy, and is part of a larger collaborative effort that includes sampling, strain isolation, strain characterization and cultivation being performed by the NREL and Canada’s NRC. Results from the NREL / NRC collaboration including specific

  6. Dewatering of Chlorella pyrenoidosa using diatomite dynamic membrane: filtration performance, membrane fouling and cake behavior.

    Science.gov (United States)

    Zhang, Yalei; Zhao, Yangying; Chu, Huaqiang; Zhou, Xuefei; Dong, Bingzhi

    2014-01-01

    The diatomite dynamic membrane (DDM) was utilized to dewater Chlorella pyrenoidosa of 2 g dry weight/L under continuous-flow mode, whose ultimate algae concentration ranged from 43 g to 22 g dry weight/L of different culture time. The stable flux of DDM could reach 30 L/m(2) h over a 24 h operation time without backwash. Influences of extracellular organic matters (EOM) on filtration behavior and membrane fouling were studied. The DDM was divided into three sub-layers, the slime layer, the algae layer and the diatomite layer from the outside to the inside of the cake layer based on components and morphologies. It was found that EOM caused membrane fouling by accumulating in the slime and algae layers. The DDM intercepted polysaccharides, protein-like substances, humic-like substances and some low-MW organics. Proteins were indicated the major membrane foulants with increased protein/polysaccharide ratio from the slime layer to the diatomite layer as culture time increased. This method could be applied to subsequent treatment of microalgae coupling technology of wastewater treatment or microalgae harvesting for producing biofuel. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Organic carbon, influent microbial diversity and temperature strongly influence algal diversity and biomass in raceway ponds treating raw municipal wastewater.

    Science.gov (United States)

    Cho, Dae-Hyun; Ramanan, Rishiram; Heo, Jina; Kang, Zion; Kim, Byung-Hyuk; Ahn, Chi-Yong; Oh, Hee-Mock; Kim, Hee-Sik

    2015-09-01

    Algae based wastewater treatment coupled to biofuel production has financial benefits and practical difficulties. This study evaluated the factors influencing diversity and growth of indigenous algal consortium cultivated on untreated municipal wastewater in a high rate algal pond (HRAP) for a period of 1 year using multivariate statistics. Diversity analyses revealed the presence of Chlorophyta, Cyanophyta and Bacillariophyta. Dominant microalgal genera by biovolume in various seasons were Scenedesmus sp., Microcystis sp., and Chlorella sp. Scenedesmus sp., persisted throughout the year but none of three strains co-dominated with the other. The most significant factors affecting genus dominance were temperature, inflow cyanophyta and organic carbon concentration. Cyanophyta concentration affected microalgal biomass and diversity, whereas temperature impacted biomass. Preferred diversity of microalgae is not sustained in wastewater systems but is obligatory for biofuel production. This study serves as a guideline to sustain desired microalgal consortium in wastewater treatment plants for biofuel production.

  8. Utilization of papaya waste and oil production by Chlorella protothecoides

    Science.gov (United States)

    Algae derived oils have outstanding potential for use in biodiesel production. Chlorella protothecoides has been shown to accumulate lipid up to 60% of its cellular dry weight with glucose supplementation under heterotrophic growth conditions. To reduce production costs, alternative carbon feedstock...

  9. Physiological Response of Algae Py ramidomonas delicatula and Chlorella saccharophila to Glyphosate Toxicity Stress%塔胞藻及海水小球藻对草甘膦致毒胁迫的生理应答

    Institute of Scientific and Technical Information of China (English)

    田密; 郑贝贝; 苏金丽; 宋秀梅; 王洪斌

    2013-01-01

    The physiological effects of herbicide glyphosate on growth and synthesis of chlorophyll a were studied in algae Pyramidomonas delicatula and Chlorella saccharophila to alert the pesticide pollution severity in water environment and to reveal potential application of marine microalgae in environmental toxicological evaluation . The results showed that the glyphosate had no inhibitory effect on the alga grow th within the concentration in all experimental groups in the first 3 days ,showing toxicity excitement at 10μL of glyphosate ,with the maximal value in 3 day ,39% higher than that in control group .From the day 4 , however , glyphosate showed significant inhibitory effect on P . delicatula and a clear dose-dependent relationship , up to the peak in 80 μL group 7 d after cultivation , the biomass in the experimental group representing 47% of the control group .Glyphosate was found to have stronger toxicity stress on C .saccharophila than on P .delicatula ,being increased with the increase in concentration and time elapse from the 2 d .In 7 day cultivation ,the biomass was found to be 27 .4% of the control group at 10 μL of glyphosate ,24 .6% at 20 μL of glyphosate ,23 .7% at 40 μL of glyphosate ,21 .9% at 60 μL of glyphosate ,and 13% at 80 μL of glyphosate .The glyphosate showed inhibitory effect on chlorophyll a of the algae ,the minimal value in 80 μL group ,and the content of chlorophyll a was only 24 .3% ( P . delicatula) and 7 .54% (C .saccharophila) of the control group .Glyphosate showed much more toxicity stress on C .saccharophila than on P . delicatula ,indicating the feasibility of C .saccharophila as the toxicological evaluation for glyphosate water pollution .%为提示农药污染对水环境破坏,揭示海洋微藻类作为环境毒理学评价指标的潜在应用,研究了塔胞藻、海水小球藻的生长及叶绿素a合成对除草剂草甘膦的致毒胁迫生理应答。试验结果表明,培养前3 d ,在试验质量浓

  10. Vitmin A, nutrition, and health values of algea: spirulina, chlorella, and dunaliella

    Science.gov (United States)

    Spirulina, chlorella, and dunalliella are unicellular algae that are commercially produced worldwide. These algae are concentrated sources of carotenoids (especially provitamin A carotenoids) and other nutrients, such as vitamin B12. Their health benefits as a complementary dietary source for macro ...

  11. Bioavailability of dissolved organic nitrogen (DON) in wastewaters from animal feedlots and storage lagoons.

    Science.gov (United States)

    Sun, Jingyi; Khan, Eakalak; Simsek, Senay; Ohm, Jae-Bom; Simsek, Halis

    2017-11-01

    Dissolved organic nitrogen (DON) from animal wastes can contribute to pollution of surface waters. Bioavailable DON (ABDON) is a portion of DON utilized by algae with or without bacteria. This study determined DON and ABDON levels in animal wastewater collected from two different sources: an animal feedlot wastewater storage tank and a sheep wastewater storage lagoon. Inocula for the ABDON bioassays were comprised of individual species and several combinations involving two algae (Chlamydomonas reinhardtii and Chlorella vulgaris) and a mixed liquor suspended solids (MLSS) bacterial culture. The ratio of initial DON to initial total dissolved nitrogen was 18% in the feedlot wastewater samples and 70% in the lagoon wastewater samples. The results showed that between 1.6 and 4.5 mg-NL-1 DON (45-79% of initial DON) in the feedlot samples and between 3.4 and 7.5 mg-NL-1 DON (36%-79% of initial DON) in the lagoon samples were bioavailable with the inocula tested. These results suggest that when considering eutrophication potential of livestock wastewater, organic nitrogen should be included in addition to the obvious culprits, ammonia and nitrate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Biological Decolorization of C.I. Basic Green 4 Solution by Chlorella sp.:Effect of Operational Parameters

    Institute of Scientific and Technical Information of China (English)

    Khataee A. R.; Pourhassan M.; Ayazloo M.

    2009-01-01

    In recent years, the ability of microorganisms to decolorize textile wastewater has received great attention due to the environmental persistence and toxicity of these pollutants. In this paper biological decolorization of triphenylmethane dye, C.I. Basic Green 4 (BG 4), by Chlorella species was investigated. The effect of operational parameters (temperature, pH, initial dye concentration and algal concentration) on decolorization efficiency was examined. Results indicated that the desired initial pH was 9. The stability and efficiency of the algae in long-term repetitive operations were also examined. Michaelis-Menten kinetics was employed to describe the apparent correlation between the decolorization rate and dye concentration. The optimal kinetic parameters, Vmax (specific decolorization rate) and Km (maximum specific decolorization rate) were 4.6 mg dye g cell-1 h-1and 151.0 mg L-1, respectively. Fig 10, Tab 2, Ref24

  13. Luxury uptake of phosphorus changes the accumulation of starch and lipid in Chlorella sp. under nitrogen depletion.

    Science.gov (United States)

    Zhu, Shunni; Wang, Yajie; Xu, Jin; Shang, Changhua; Wang, Zhongming; Xu, Jingliang; Yuan, Zhenhong

    2015-12-01

    The aim of this research was to study the effect of phosphorus supply on starch and lipid production under nitrogen starvation using Chlorella sp. as a model. High phosphate level had marginal effect on cell density but increased biomass growth. Massive phosphorus was assimilated quickly and mainly stored in the form of polyphosphate. The algal cells ceased phosphorus uptake when intracellular phosphorus reached a certain level. 5mM phosphate in the culture rendered a 16.7% decrease of starch synthesis and a 22.4% increase of lipid synthesis relative to low phosphate (0.17 mM). It is plausible that phosphate can regulate carbon partitioning between starch and lipid synthesis pathway by influencing ADP-glucose pyrophosphorylase activity. Moreover, high phosphate concentration enhanced the abundance of oleic acid, improving oil quality for biodiesel production. It is a promising cultivation strategy by integration of phosphorus removal from wastewater with biodiesel production for this alga.

  14. Light scattering on chlorella vulgaris cells

    Science.gov (United States)

    Krol, Tadeusz; Zielinski, Andrzej; Witkowski, Konrad

    1992-12-01

    Laboratory measurements of light scattering on the axenic cultures of unicellular alga Chlorella vulgaris monoculture confirm the thesis of multi-level light scattering by the cell i.e., both by outer cell membrane and the internal structure of the cell, as well as by its molecular structures. In the measurements, the technique of dynamic light scattering and analysis by the regulation method was used, indicate that the light scattering phenomenon is affected by particles of sizes corresponding either to overall dimensions of the cell or to the dimensions of its internal structures. A correlation was found between the suggested sizes and the stage of physiological evolution of the culture. The measurements of 10 functions constituting the elements of the scattering matrix for an alive Chlorella vulgaris culture and cultures with internal cell structures modified by chemical and mechanical agents evidence that the internal structures of cells play an important role in the interaction of phytoplankton and light.

  15. [Culture medium based on biogas slurry and breeding of oil Chlorella].

    Science.gov (United States)

    Zhao, Feng-Min; Mei, Shuai; Cao, You-Fu; Ding, Jin-Feng; Xu, Jia-Jie; Li, Shu-Jun

    2014-06-01

    The oil chlorella cultivation and biogas slurry treatment were combined. The biogas slurry provided water and nutrient for growing chlorella, at the same time, harmless treatment of biogas slurry was realized. This paper cultivated 4 species of oil chlorella in the mixed medium of biogas slurry and green algae medium (the volume ratios were 1 : 9, 1 : 3, 1 : 1 and 3 : 1, respectively), and compared their oil productivity to select the best oil chlorella species and the optimal culture medium. The results showed that, the combination of medium and chlorella species to reach the highest oil productivity was a volume ratio of 1 : 3 and the chlorella species BJ05, and the oil productivity of chlorella BJ05 was 9.20 mg x (L x d)(-1), higher than that in green algae medium [8.66 mg x (L x d)(-1)]. In mixed medium with a volume ratio of 1:3, the effect of adding different nutrients into the green algae medium on the oil productivity was examined, and the results showed that, sodium carbonate and citric acid had no negative effect on the oil productivity of chlorella BJ05. in the absence of sodium carbonate and citric acid, the oil productivity of chlorella BJ05 was 9.36 mg x (L x d)(-1), and the removal of COD (chemical oxygen demand), total nitrogen, total phosphorus and ammonia nitrogen rates were 59%, 75%, 61% and 100%, respectively. Deficiency in other nutrients had negative effect on the oil productivity. Therefore, the culture medium was further optimized to the mixed medium of biogas slurry and green algae medium with a volume ratio of 1 : 3 and without addition of sodium carbonate and citric acid.

  16. Toxicological assessment of hospital wastewater in different treatment processes.

    Science.gov (United States)

    Hamjinda, Nutta Sangnarin; Chiemchaisri, Wilai; Watanabe, Toru; Honda, Ryo; Chiemchaisri, Chart

    2015-06-24

    This study surveyed the hospital wastewater characters focusing on antibiotic contamination in seven hospitals in Bangkok. It detected 19 antibiotics of which the high-frequent detection were quinolones such as ofloxacin + levofloxacin, norfloxacin, ciprofloxacin including sulfamethoxazole. Norfloxacin and ciprofloxacin appeared the highest concentrations of 12.11 and 9.60 μg/L, respectively. Most antibiotic concentrations in the wastewaters of the studied hospitals gave a good correlation (r (2)  = 0.77-0.99) to the amount of usage. In this study, batch acute toxicity tests were performed to assess the toxicity of hospital wastewater on mixed liquor, freshwater algae (Chlorella vulgaris and Scenedesmus quadricauda), and microcrustacean (Moina macrocopa). The hospital wastewaters could inhibit the mixed liquor growth and gave similar toxic levels among test species: algae and microcrustacean (9.81-13.63 and 2.62-3.09 TU, respectively). The conventional activated sludge (CAS) and rotating biological contactor (RBC) could remove fluoroquinolones and tetracycline via biomass adsorption. After treatment, most of treatment could reduce the toxicity. Nevertheless, the effluent gave slight toxicity on some test species which might be caused from chlorination and a common toxicant (NH3-N).

  17. Mixotrophic cultivation of Chlorella vulgaris with primary piggery wastewater%初级猪粪废水混合培养普通小球藻的研究

    Institute of Scientific and Technical Information of China (English)

    朱静静; 杨巍; 纪九军; 王海英

    2014-01-01

    实验研究了初级猪粪废水混合培养一株普通小球藻(Chlorella vulgaris)的可行性.实验结果表明,初级猪粪废水可直接进行C.vulgaris的培养,不需要添加微量金属元素,生物量最大可达0.414 g/L,为在Bristol培养基培养的生物量的3.14倍.C.vulgaris可以耐受1 000 mg/L COD的猪粪水,在250~1 000 mg/L范围内,C.vulgaris生物量随初始COD的升高而升高,猪粪水中的营养物质被高效地去除,其中猪粪水中的总氮、总磷和氨氮的去除率分别达到了50%,60%和90%以上.C.vulgaris的油脂含量达到22.28%,实现了初级猪粪废水中微藻的生物量转化和资源化处理.

  18. WATER CONDITION IN CELLS OF CHLORELLA

    Directory of Open Access Journals (Sweden)

    I. V. Kuznetsova

    2015-01-01

    Full Text Available The water condition in cages of the paste of chlorella was investigated by the method of thermogravimetric analysis. With increasing heating rate endothermic effect corresponding to the dehydration process is shifted towards higher temperatures. Temperature intervals of chlorella dehydration are defined at rate of heating 2 К/min - 308-368 K, 5 К/min - 323-403 K, and 10 К/min - 348-403 K. Quantitative characteristics of kinetic unequal water in chlorella have been received for each step (∆, ∆Т, a mass fraction (w, energy of activation (Еа. This process is similar to the process of the dehydration in ion exchange membranes. The derived kinetic characteristics give the possibility to define an optimum temperature interval and rate of drying microalgae for the purpose of increase of periods of storage in the form of paste or a solid substance for the further use as the bioadditive. In addition the presence of three types of water chlorella in a cell set according to NMR with pulsed magnetic field gradient. Since free water is involved in biochemical, chemical and microbiological processes, it is desirable to remove during drying of the preparation. The resulting temperature range of 323-343 K (step 2 at a heating rate of 2 K / min corresponds to a temperature range of drying the chlorella in a production environment. It should be noted that the highest number of algae in a tightly-water (the last stage. Apparently, this is determined by a unique cell structure. Temperature ranges dehydration process are not clear and vary depending on the heating rate, which is fully in line with previous studies of thermal analysis for grains, vegetables and bakery products.

  19. COMPARISON OF THE ABILITY TO ABSORB METALLIC IONS IN WASTEWATER BY DIFFERENT STRAINS OF CHLORELLA%不同小球藻对工业废水中金属离子吸附能力比较

    Institute of Scientific and Technical Information of China (English)

    吴能表; 付启昌; 龙云; 阳义健; 朱利泉; 王小佳

    2005-01-01

    研究了5种小球藻(Chlorella phyrenoidosa,Chlorella vulgaris,Chlorella ellipsoidea,Chlorella sorokiniana,Chlorellasp.)对电镀厂污水中部分金属离子的吸附情况.结果表明:各种小球藻对测定的Zn2+,Cu2+,Ni2+,Cr3+等金属离子都有一定吸附能力,不同小球藻对同一离子的吸附能力存在差异,同一小球藻对不同离子的吸附能力有不同.综合看来,Chlorellaphyrenoidosa和Chlorella vulgaris对上述离子都有较好的吸收.

  20. Experimental study on the removal of ammonia nitrogen and total nitrogen with algae from coal-gasification wastewater%藻类去除煤气化废水氨氮及总氮的实验研究

    Institute of Scientific and Technical Information of China (English)

    刘肃力; 纪钦洪; 于广欣; 卿人韦

    2013-01-01

    The column photo-bioreactor has been used for algae removing ammonia nitrogen and total nitrogen with algae from coal-gasification wastewater.Experimental results show that under the optimized conditions,Scenedesmus quadricanda,Scnedesmus obliquus and compound algae (Tribonema and Phormidium) can make statistically thorough removal of the ammonia nitrogen from coal-gasification wastewater within 3 d,and the removing efficiency of total nitrogen from coal-gasification wastewater has reached the maximum on the 5th day,which is 86.02% with Scenedesmus quadricanda,83.33% with Senedesmus obliquus,and 71.81% with the compound algae.The results reveal that it is feasible to remove ammonia nitrogen and total nitrogen from coal gasification wastewater by using appropriate algae.Besides,compared with the biological nitrification/denitrification denitrogenation process,the process is also significantly original.%采用柱式光合反应器对藻类去除煤气化废水的氨氮及总氮开展了探索性实验研究.实验结果表明:优化条件下,四尾栅藻、斜生栅藻、混合藻(黄丝藻和席藻)都在3d内完全去除氨氮,同时总氮去除率都在第5天达到最大,分别是四尾栅藻86.02%,斜生栅藻83.33%,混合藻71.81%.说明选用合适的藻类去除煤气化废水的氨氮及总氮可行,同时相比生物硝化/反硝化脱氮工艺该方法具有一定的新颖性.

  1. Toward an Ecologically Optimized N:P Recovery from Wastewater by Microalgae

    Directory of Open Access Journals (Sweden)

    Tânia V. Fernandes

    2017-09-01

    Full Text Available Global stores of important resources such as phosphorus (P are being rapidly depleted, while the excessive use of nutrients has led to the enrichment of surface waters worldwide. Ideally, nutrients would be recovered from wastewater, which will not only prevent eutrophication but also provide access to alternative nutrient stores. Current state-of-the-art wastewater treatment technologies are effective in removing these nutrients from wastewater, yet they can only recover P and often in an insufficient way. Microalgae, however, can effectively assimilate P and nitrogen (N, as well as other macro- and micronutrients, allowing these nutrients to be recovered into valuable products that can be used to close nutrient cycles (e.g., fertilizer, bioplastics, color dyes, and bulk chemicals. Here, we show that the green alga Chlorella sorokiniana is able to remove all inorganic N and P present in concentrated toilet wastewater (i.e., black water with N:P ratios ranging between 15 and 26. However, the N and P uptake by the algae is imbalanced relative to the wastewater N:P stoichiometry, resulting in a rapid removal of P but relatively slower removal of N. Here, we discuss how ecological principles such as ecological stoichiometry and resource-ratio theory may help optimize N:P removal and allow for more effective recovery of N and P from black water.

  2. Effect of algae growth on aerobic granulation and nutrients removal from synthetic wastewater by using sequencing batch reactors.

    Science.gov (United States)

    Huang, Wenli; Li, Bing; Zhang, Chao; Zhang, Zhenya; Lei, Zhongfang; Lu, Baowang; Zhou, Beibei

    2015-03-01

    The effect of algae growth on aerobic granulation and nutrients removal was studied in two identical sequencing batch reactors (SBRs). Sunlight exposure promoted the growth of algae in the SBR (Rs), forming an algal-bacterial symbiosis in aerobic granules. Compared to the control SBR (Rc), Rs had a slower granulation process with granules of loose structure and smaller particle size. Moreover, the specific oxygen uptake rate was significantly decreased for the granules from Rs with secretion of 25.7% and 22.5% less proteins and polysaccharides respectively in the extracellular polymeric substances. Although little impact was observed on chemical oxygen demand (COD) removal, algal-bacterial symbiosis deteriorated N and P removals, about 40.7-45.4% of total N and 44% of total P in Rs in contrast to 52.9-58.3% of TN and 90% of TP in Rc, respectively. In addition, the growth of algae altered the microbial community in Rs, especially unfavorable for Nitrospiraceae and Nitrosomonadaceae.

  3. The Optimizing of Growth and Quality of Chlorella vulgaris as ASUH feed supplement for Broiler

    Directory of Open Access Journals (Sweden)

    Salvia Salvia

    2014-01-01

    Full Text Available Chlorella is spherical single celled freshwater micro-algae.   Chlorella  has potentials as element of ration or natural ASUH (safe, healthy, whole and halal feed supplement for it contains nutrition and active component, decreases cholesterol level and resulting darker yolk.  Chlorella vulgaris  is type of green algae   which, its economical potential need to be revealed. Variety of components of growing media is one of factors determining quality of microalgae. In terms of mass production, it is important to find correct, cheap and easy to feed nutrition for breeders. The objective of the research is to find out the optimizing of growth and quality of Chlorella vulgaris   as ASUH feed supplement for broiler. Test using sedgwick rafter method conducted to find out the optimizing of growth and quality of  Chlorella vulgaris  while AOAC method applied to test quality of its nutrition. The result shows that.  Chlorella vulgaris  grew well at technical medium 10 % of Phyto-s, crude protein 57.63%, fat  5.84%, b Carotene 6.44 mg/gram, Vitamin C 4.12 mg/gram and vitamin E 1.32 mg/gram. We can say that Chlorella vulgaris  potential to be natural and ASUH feed supplement and Phyto-s can be used as nutrition for mass production.

  4. [Recent progress in treatment of aquaculture wastewater based on microalgae--a review].

    Science.gov (United States)

    Meng, Fanping; Gong, Yanyan; Ma, Dongdong

    2009-06-01

    Microalgae enables aquaculture wastewater recycling through a biological conversion. Recently, many studies have been reported on microalgae cultivation and wastewater treatment, including developing various wastewater treatment technologies such as algae pond, activated algae, immobilized algae and algae photo-bioreactor. In this review, we address the mechanisms, progress and application in the purification of aquaculture wastewater, as well as some research perspectives.

  5. The adsorption potential and recovery of thallium using green micro-algae from eutrophic water sources.

    Science.gov (United States)

    Birungi, Z S; Chirwa, E M N

    2015-12-15

    Thallium (Tl) is a highly volatile and toxic heavy metal regarded to cause pollution even at very low concentrations of several parts per million. Despite the extremely high risk of Tl in the environment, limited information on removal/recovery exists. The study focussed on the use of green algae to determine the sorption potential and recovery of Tl. From the study, removal efficiency was achieved at 100% for lower concentrations of ≥150 mg/L of Tl. At higher concentrations in a range of 250-500 mg/L, the performance of algae was still higher with sorption capacity (qmax) between 830 and 1000 mg/g. Generally, Chlorella vulgaris was the best adsorbent with a high qmax and lower affinity of 1000 mg/g and 1.11 L/g, respectively. When compared to other studies on Tl adsorption, the tested algae showed a better qmax than most adsorbents. The kinetic studies showed better correlation co-efficient of ≤0.99 for Pseudo-second order model than the first order model. Recovery was achieved highest for C. vulgaris using nitric acid at 93.3%. The strongest functional groups responsible for Tl binding on the algal cell wall were carboxyl and phenols. Green algae from freshwater bodies showed significant potential for Tl removal/recovery from industrial wastewater.

  6. Removal of Heavy Metal Ions from Wastewater by Using Biosorbents from Marine Algae-A Cost Effective New Technology

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Heavy metal pollution from industrial wastewater is a worldwide environmental issue. Biosorption of heavy metals by using biosorbents derived from various types of biomass has been shown to be effective for the uptake of heavy metal ions. In this study, biosorbents derived from the biomass of a group of marine macroalgae were used for the removal and recovery of heavy metal ions from aqueous solutions. Results indicated that the biosorbents have high uptake capacities and affinities for a number of heavy metal ions. The uptake capacities of the biosorbents were in the range of 1.0 to 1.5mmol·g-1 for divalent heavy metal ions. The kinetics of the uptake process was fast and the process can be used in both batch and fixed-bed operations. It appears that the biosorption process by using biosorbents from marine macroalgae can be an efficient and cost effective technology for the treatment of heavy metal containing wastewater.

  7. [Simultaneously removal of COD, nitrogen and phosphorus from wastewater by coupling treatment system with immobilized algae-bacteria].

    Science.gov (United States)

    Deng, Xu; Wei, Bin; Hu, Zhang-Li

    2011-08-01

    A coupling treatment system was developed by employing immobilized Chlamydomonas reinhardti and activated sludge to simultaneously remove COD, nitrogen and phosphorus from wastewater. The amount of wastewater treated by the system was 6 m3 per day, and hydraulic retention time was 12 h. For activated sludge section, as stirring rate of anaerobic tank was 15 r x min(-1) and DO value of aerobic tank was 5 mg x L(-1), COD decreased from about 150 mg x L(-1) to 50 mg x L(-1) and NH4+-N from 20-30 mg x L(-1) to 0.5 mg x L(-1), whereas TP only dropped from 2-3 mg x L(-1) to 1.0 mg x L(-1). For immobilized C. reinhardti section, the suitable conditions were: DO 5 mg x L(-1), illumination intensity 2000 lx, the loading ratio of immobilization pellets 20%, respectively. Under the appropriate conditions of the coupling treatment system, COD, NH4+-N and TP of the effluent were about 15 mg x L(-1), 0.5 mg x L(-1) and 0.5 mg x L(-1), respectively. During 2 months period of continuous treatment, COD, NH4+-N and TP of the effluent kept fairly constant, showing the stability of the coupling wastewater treatment system.

  8. Algae Derived Biofuel

    Energy Technology Data Exchange (ETDEWEB)

    Jahan, Kauser [Rowan Univ., Glassboro, NJ (United States)

    2015-03-31

    One of the most promising fuel alternatives is algae biodiesel. Algae reproduce quickly, produce oils more efficiently than crop plants, and require relatively few nutrients for growth. These nutrients can potentially be derived from inexpensive waste sources such as flue gas and wastewater, providing a mutual benefit of helping to mitigate carbon dioxide waste. Algae can also be grown on land unsuitable for agricultural purposes, eliminating competition with food sources. This project focused on cultivating select algae species under various environmental conditions to optimize oil yield. Membrane studies were also conducted to transfer carbon di-oxide more efficiently. An LCA study was also conducted to investigate the energy intensive steps in algae cultivation.

  9. Toxicity assessment of Chlorella vulgaris and Chlorella protothecoides following exposure to Pb(II).

    Science.gov (United States)

    Zhang, Wei; Xiong, Bang; Chen, Lin; Lin, Kuangfei; Cui, Xinhong; Bi, Huasong; Guo, Meijin; Wang, Weiliang

    2013-07-01

    The short- and long-term toxic effects of Pb(II) exposure on Chlorella vulgaris (C. vulgaris) and Chlorella protothecoides (C. protothecoides) were not well understood. The lab study was performed to observe the Pb(II) exposure induced changes. Results of the observations show: (1) higher level of Pb(II) (50 or 80mgL(-1)) could significantly inhibit the growth and chlorophyll a synthesis of both algae in almost all the treatments and dose-response relationships could be clearly observed, (2) the range of EC50 values (24-120h, 67.73-172.45mgL(-1)) indicated that Pb(II) had a relatively limited short-term toxicity to the two algae, while long-term tests (7-28d, 50.41-63.91mgL(-1)) displayed higher toxicity and (3) SOD and CAT activities of both algae after exposed to medium level of Pb(II) were significantly promoted, and their response might be more susceptible in short-term exposure. This research provides a basic understanding of Pb(II) toxicity to aquatic organisms.

  10. Algae fuels : a tantalizing alternative

    Energy Technology Data Exchange (ETDEWEB)

    Granson, E.

    2010-11-15

    This article surveyed the current state of research and development in the area of algae use as a basis for fuel and as a feedstock for the chemical industry. The constraints inhibiting the commercialization of algae-related processes were discussed and a brief overview of the history of algae research was presented. Interest in algae research has ebbed and flowed in conjunction with economic and social concerns. It is unknown whether algae can be grown on a scale and cost that is commercially viable. A bench-scale algae cultivation system involving photobioreactors was described. Algae are increasingly being used in treating wastewater from industrial processes, as algae can reduce ammonia and phosphate loads in effluent. Exhaust carbon dioxide is being used to feed algae crops. Advances are needed to make turning algae oil into fuel cost effective. A bench-stage process for extracting algae oil from water for biofuel conversion was described. The process results in easier-to-dry biomass without using chemical solvents or centrifuges. Algae biomass is also being explored for used as a polymer feedstock. Algae can be grown anywhere there is sun, but the challenge is in developing a large enough supply of algae biomass. Second generation algae plastic products will be more complex and may involve the creation of a monomer out of algae itself, which could make algae competitive with oil in the plastics industry. Skeptics doubt that algae processes can be commercialized, but some within the industry believe that algae biomass will eventually work within the norms of industrial processes. 5 figs.

  11. PRODUCTIVITY OF MICROALGAE CHLORELLA VULGARIS IN LABORATORY CONDITION

    Directory of Open Access Journals (Sweden)

    Agnieszka Patyna

    2017-06-01

    Full Text Available Algae biomass is increasingly regarded as a potential resource that could be used to produce biofuels, electricity and heat. Algae contain a lot of nutrients, so they can be used as food for humans and livestock. Because of their valuable composition (many nutrients they are used as supplements of balanced diet, in turn taking into account their biosorption abbility they are used to detoxification of human body. Algae cultivation does not demand large areas of land to expose cells to sunlight, so their production rate is higher than vascular plants. Moreover algae cultivation lets to achieve high biomass concentration. Important cultivation factors are: illumination (light intensity is an important factor because it drives photosynthesis, CO2 supply, culture medium and mixing. The experimental research was conducted using Chlorella vulgaris BA 002 strain. The aim of this study was to determine the effectiveness of biomass growth in laboratory condition.

  12. Toxicity of reactive red 141 and basic red 14 to algae and waterfleas.

    Science.gov (United States)

    Vinitnantharat, S; Chartthe, W; Pinisakul, A

    2008-01-01

    Textile wastewater normally has a visible color although it has low concentration. This may affect the aquatic ecosystem. Two dyestuffs, Reactive Red 141 (RR141) and Basic Red14 (BR14) were used as compound models. RR 141 is an anionic dye which has a big molecule whereas BR 14 is a cationic dye and has a small molecule. The target organisms for toxicity test were green algae (Chlorella sp.) and waterfleas (Moina macrocopa). The effect of humic acid on the toxicity of dyestuffs to test organisms was also investigated. From the observation of cell counts, Chlorophyll a and dry weight of algae in the dye solutions for 4 days, it was found that all parameters increased as times increased. This revealed that algae could utilize dyestuffs as a carbon source. However, BR14 gave higher absorbance than RR141 at the wavelength of 430 nm which competed to the Chlorophyll a for algal photosynthesis. This resulted in the 96-h EC50 of BR14 and RR141 to Chlorella sp. were 10.88 and 95.55 mg/L, respectively. As for dye toxicity to waterfleas, the 48-h LC50 of BR14 and RR141 to waterfleas were 4.91 and 18.26 mg/L, respectively. The high toxicity of BR14 to waterfleas related to the small molecule of dye could pass into the cell and was absorbed by organelles of waterfleas. Toxicity of BR14 in humic acid solution to Chlorella sp. showed less toxic than RR141 in humic acid solution. This dues to the negative charge of humic acid could bound with a positive charge of BR14, resulted in low amount of BR14 remaining in the bulk solution. The toxicity of BR14 and RR141 in humic acid solution to waterfleas was increased as humic acid increased. Hence, the proper treatment of textile wastewater to yield low concentration of dyes in the effluent before discharging to the natural water is needed. IWA Publishing 2008.

  13. The effect of low-temperature pretreatment on the solubilization and biomethane potential of microalgae biomass grown in synthetic and wastewater media.

    Science.gov (United States)

    Kinnunen, V; Rintala, J

    2016-12-01

    Microalgae have been suggested as a sustainable raw material for biofuel production in the form of methane via anaerobic digestion. Here, pretreatments at 60-80°C were investigated, aiming to study the impact of algae culture media on biomethane potential and pretreatment efficiency. Chlorella vulgaris and mixed culture of native algae species (dominating by Scenedesmus sp.) were grown in synthetic medium, wastewater (sterilized and non-sterilized) and digestate from anaerobic digestion of pulp and paper biosludge (sterilized and non-sterilized). The biomethane potential for native microalgal biomass varied between 154 and 252LCH4kg(-1) VS depending on culture media. The efficiency of the low-temperature pretreatment (80°C, 3h) for solubilization (9-12%) of C. vulgaris and native algae biomass was similar for algae grown in sterilized and non-sterilized wastewater media. The pretreatment increased the biomethane potential of native algae biomass by 11-24%. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Assessing Nutrient Removal Kinetics in Flushed Manure Using Chlorella vulgaris Biomass Production

    Directory of Open Access Journals (Sweden)

    Pramod Pandey

    2017-07-01

    Full Text Available The utilization of dairy wastewater for producing algal biomass is seen as a two-fold opportunity to treat wastewater and produce algae biomass, which can be potentially used for production of biofuels. In animal agriculture system, one of the major waste streams is dairy manure that contains high levels of nitrogen and phosphorus. Furthermore, it is produced abundantly in California’s dairy industry, as well as many other parts of the world. We hypothesized that flushed manure, wastewater from a dairy farm, can be used as a potential feedstock after pretreatment to grow Chlorella vulgaris biomass and to reduce nutrients of manure. In this study, we focused on investigating the use of flushed manure, produced in a dairy farm for growing C. vulgaris biomass. A series of batch-mode experiments, fed with manure feedstock and synthetic medium, were conducted and corresponding C. vulgaris production was analyzed. Impacts of varying levels of sterilized manure feedstock (SMF and synthetic culture medium (SCM (20–100% on biomass production, and consequential changes in total nitrogen (TN and total phosphorus (TP were determined. C. vulgaris production data (Shi et al., 2016 were fitted into a model (Aslan and Kapdan, 2006 for calculating kinetics of TN and TP removal. Results showed that the highest C. vulgaris biomass production occurs, when SMF and SCM were mixed with ratio of 40%:60%. With this mixture, biomass on Day 9 was increased by 1,740% compared to initial biomass; and on Day 30, it was increased by 2,456.9%. The production was relatively low, when either only SCM or manure feedstock medium (without pretreatment, i.e., no sterilization was used as a culture medium. On this ratio, TN and TP were reduced by 29.9 and 12.3% on Day 9, and these reductions on Day 30 were 76 and 26.9%, respectively.

  15. [Isolation, Identification and Characteristic Analysis of an Oil-producing Chlorella sp. Tolerant to High-strength Anaerobic Digestion Effluent].

    Science.gov (United States)

    Yang, Chuang; Wang, Wen-guo; Ma, Dan-wei; Tang, Xiao-yu; Hu, Qi-chun

    2015-07-01

    A Chlorella strain tolerant to high-strength anaerobic digestion effluent was isolated from the anaerobic digestion effluent with a long-term exposure to air. The strain was identified as a Chlorella by morphological and molecular biological methods, and named Chlorella sp. BWY-1, The anaerobic digestion effluent used in this study was from a biogas plant with the raw materials of swine wastewater after solid-liquid separation. The Chlorella regularis (FACHB-729) was used as the control strain. The comparative study showed that Chlorella sp, BWY-Ihad relatively higher growth rate, biomass accumulation capacity and pollutants removal rate in BG11. and different concentrations of anaerobic digestion effluent. Chlorella sp. BWY-1 had the highest growth rate and biomass productivity (324.40 mg.L-1) in BG11, but its lipid productivity and lipid content increased with the increase of anaerobic digestion effluent concentration, In undiluted anaerobic digestion effluent, the lipid productivity and lipid content of Chlorella sp. BWY-1 were up to 44. 43% and 108. 70 mg.L-1, respectively. Those results showed that the isolated algal strain bad some potential applications in livestock wastewater treatment and bioenergy production, it could be combined with a solid-liquid separation, anaerobic fermentation and other techniques for processing livestock wastewater and producing biodiesel.

  16. An Overview of Algae Biofuel Production and Potential Environmental Impact

    Science.gov (United States)

    Algae are among the most potentially significant sources of sustainable biofuels in the future of renewable energy. A feedstock with virtually unlimited applicability, algae can metabolize various waste streams (e.g., municipal wastewater, carbon dioxide from industrial flue gas)...

  17. An Overview of Algae Biofuel Production and Potential Environmental Impact

    Science.gov (United States)

    Algae are among the most potentially significant sources of sustainable biofuels in the future of renewable energy. A feedstock with virtually unlimited applicability, algae can metabolize various waste streams (e.g., municipal wastewater, carbon dioxide from industrial flue gas)...

  18. Construction of a transformation system for the stable expression of foreign genes in Chlorella sp.

    Institute of Scientific and Technical Information of China (English)

    Wang Yiyun; Gao Xiaorong; Wang Changhai

    2007-01-01

    A stable transformation system for the expression of foreign genes in the unicellular green marine alga (Chlorella sp. MACC/C95) was established. Using electroporation, the alga was transformed with a plasmid containing the phytase gene under the control of CaMV35S promoter and the neomycin phosphotransferase(npt)as a seleetable marker gene. The integration of the phytase gene into the Chlorella genome was revealed by PCR and Southern blotting analysis. RT-PCR analysis revealed the expression of phytasegene at the transcript level. The enhanced activity of phytase enzyme in the transformants confirmed the integration and successful expression of phytase gene. The introduced phytase gene and its protein expression were stably maintained for at least 30 generations in media devoid of selectable antibiotics G418. This is an important step toward the production of useful foreign proteins in Chlorella sp. MACC/C95.

  19. Microbial fuel cell with an algae-assisted cathode: A preliminary assessment

    Science.gov (United States)

    González del Campo, Araceli; Cañizares, Pablo; Rodrigo, Manuel A.; Fernández, Francisco J.; Lobato, Justo

    2013-11-01

    A microbial fuel cell (MFC) with an algae-assisted cathode, i.e., a system where the oxygen required by the cathode is not provided by aeration but by the photosynthetic process of the algae (Chlorella vulgaris), has been studied. The cathode was illuminated for 12 h each day (from 8:00 h to 20:00 h). 25 days was necessary to achieve steady state conditions. The time evolution of dissolved oxygen and cell voltage were assessed over the course of each day. As expected, the dissolved oxygen values were not constant throughout the day, reaching maximum values between 14:00 h and 20:00 h when dark phase reactions began and the algae started to consume oxygen. Cell voltage (Rext 120 Ω) followed the same trend as the oxygen profile. The supply of CO2 in the cathode was also studied, and half an hour was enough time to get the system working properly. During the acclimation stage, power density increased up to 13.5 mW m-2 at steady state conditions. However, impedance analysis showed that polarization resistance was higher at the cathode than at the anode. Nevertheless, it can be concluded that the studied system is a feasible method to treat wastewater in a self-sustainable way.

  20. Growing Chlorella vulgaris in Photobioreactor by Continuous Process Using Concentrated Desalination: Effect of Dilution Rate on Biochemical Composition

    Directory of Open Access Journals (Sweden)

    Ângelo Paggi Matos

    2014-01-01

    Full Text Available Desalination wastewater, which contains large amount of salt waste, might lead to severely environmental pollution. This study evaluated the effect of dilution rate (0.1≤D≤0.3 day−1 on microalgal biomass productivity, lipid content, and fatty acid profile under steady-state condition of Chlorella vulgaris supplemented with concentrated desalination. Continuous culture was conducted for 55 days. Results show that the biomass productivity (Px varied from 57 to 126 mg L−1 d−1 (dry mass when the dilution rate ranged from 0.1 to 0.3 day−1. At lowest dilution rate (D=0.1 day−1, the continuous culture regime ensured the highest values of maximum biomass concentration (Xm=570±20 mL−1 and protein content (52%. Biomass lipid content was an increasing function of D. The most abundant fatty acids were the palmitic (25.3±0.6% at D=0.1 day−1 and the gamma-linolenic acid (23.5±0.1% at D=0.3 day−1 ones. These fatty acids present 14 to 18 carbons in the carbon chain, being mainly saturated and polyunsaturated, respectively. Overall, the results show that continuous culture is a powerful tool to investigate the cell growth kinetics and physiological behaviors of the algae growing on desalination wastewater.

  1. 三氯异氰尿酸与盐酸环丙沙星对蛋白核小球藻的毒性效应%Toxic effects of trichloroisocyanuric acid and ciprofloxacin hydrochloride on a freshwater alga, chlorella pyrenoidosa

    Institute of Scientific and Technical Information of China (English)

    聂湘平; 王翔; 陈菊芳; 鹿金雁; 李潇; 杨永涛

    2007-01-01

    测试了典型渔药三氯异氰尿酸(Trichloroisocyanuric acid,TCCA)、盐酸环丙沙星(Ciprofloxacin hydrochloride,CPFX)对蛋白核小球藻(Chlorella pyrenoidosa)的急性毒性及其Ⅰ相、Ⅱ相代谢酶活性的影响.结果表明,TCCA和CPFX作用小球藻96h后EC50分别为0.31 mg·L-1和20.61mg·L-1.TCCA在低浓度下对小球藻Ⅰ、Ⅱ相代谢酶GSH、GST、CAT和EROD都存在诱导作用,当TCCA浓度大于0.13 mg·L-1时,对GSH、GST和EROD的诱导减弱.GSH、GST、EROD三种酶对CPFX作用的响应较弱,当CPFX大于70.20mg·L-1时,GST受到显著抑制,而EROD则明显升高,与对照组差异显著,GSH没有明显变化.CAT对CPFX作用的响应较敏感,表现为典型适应性诱导现象"钟形曲线",适合作为CPFX暴露的生物标记物.

  2. First case of Chlorella wound infection in a human in Australia

    Directory of Open Access Journals (Sweden)

    J. Hart

    2014-07-01

    Full Text Available A 30-year-old man developed an infected knee wound 2 days after jumping his bicycle into a freshwater dam. He required repeated debridement and tissue grew bright green colonies typical of the alga Chlorella plus Aeromonas hydrophila. This, and one previously reported case, responded to surgical debridement and careful wound management.

  3. Pertumbuhan Chlorella sp. pada beberapa konsentrasi limbah batubara (The growth rate of the Chlorella sp. at different concentrations of coal waste water

    Directory of Open Access Journals (Sweden)

    Zerli Selvika

    2016-12-01

    Full Text Available Chlorella sp. is a single-celled microalga that mostly grows in marine waters. Chlorella sp. can grow in heavy polluted waters and therefore it has potency as a bioremediation agent. This study aimed was to analyze the effect of coal on the growth of Chlorella sp. in plant isolation media and the quality of water in plant isolation media for Chlorella sp. The complete randomized design with 4 treatments of coal concentration was used in this study. Four concentration concentrations were tested namely, 0 ppt, 1 ppt, 3 ppt and 5 ppt. The results revealed that coal with different concentrations gave no significant effect on the growth of Chlorella sp. (p> 0.05. The density among the concentrations of 0 ppt, 1 ppt, 3 ppt and 5 ppt were not significantly different. In addition, the coal concentration gave no significant effect on temperature, salinity and potential hydrogen (pH (p>0.05. The Chlorella sp. can grow in the polluted water by coal, and therefore this alga can be used as potential organisms for bioremediation of coal waste. Chlorella sp. merupakan mikroalga bersel satu yang banyak tumbuh di perairan laut. Chlorella sp. dapat tumbuh di perairan yang tercemar berat sehingga berpotensi sebagai bioremediator. Penelitian ini bertujuan untuk menganalisis pengaruh konsentrasi batubara terhadap pertumbuhan Chlorella sp. dan kualitas air pada media kultur Chlorella sp. Metode yang digunakan dalam penelitian ini adalah metode eksperimen skala laboratorium. Rancangan percobaan yang digunakan adalah rancangan acak lengkap dengan 4 perlakuan konsentrasi batubara 0 ppt, 1 ppt, 3 ppt dan 5 ppt. Hasil penelitian menunjukkan bahwa batubara dengan konsentrasi yang berbeda tidak berpengaruh nyata terhadap laju pertumbuhan Chlorella sp (P>0,05. Kepadatan antara konsentrasi 0 ppt, 1 ppt, 3 ppt dan 5 ppt tidak terlalu jauh berbeda. Konsentrasi batubara juga tidak berpengaruh nyata terhadap parameter suhu, salinitas dan derajat keasaman (pH (p>0,05. Chlorella sp

  4. Study on Effect of Efficient Algae Pond on Purification Performance of Aquaculture Wastewater in Small Town%高效藻类塘对小城镇养殖废水净化效能的影响

    Institute of Scientific and Technical Information of China (English)

    徐运清; 胡超

    2011-01-01

    [目的]探索高效藻类螗中藻类、曝气和底泥对小城镇养殖废水净化效能的影响.[方法]设置4个独立人工池塘作对比试验,通过控制试验塘中的藻类浓度、底泥及曝气程度,测定养殖废水中的还原性物质、氮和磷的变化量,进而比较藻类、底泥和曝气对废水净化效能的影响.[结果]高效藻类塘对还原性物质、氟和磷的去除率分别达到88.3%、69.2%和59.7%,而普通塘对其去除率分别仅有48.0%,43.4%和22.8%.藻类对TP的去除影响最为明显,其次是对COD,对TN的影响最弱;曝气对COD代表的还原性物质的去除率影响最大,其次是对TN的降低,对TP的影响最弱;底泥对TP的去除影响极为显著,其次是对TN,而对.COD的降低影响最弱.[结论]高效藻类塘中藻类、曝气和底泥均对养殖废水的净化产生较大影响.%[ Objective] The study aimed to explore the effects of algae, aeration and sediment in the efficient algae pond on the purification performance of the aquaculture wastewater in small town. [ Method ] In the test, 4 independent artificial ponds were set up as the contrast experiment, and through controlling the algae concn., sediment and aeration degree, the change of reducible substance, nitrogen and phosphorus in the aquaculture wastewater were determined to compared the effects of algae, aeration and sediment on the purification performance of the aquaculture wastewater. [ Result] In the efficient algae pond the removal rate of nitrogen and phosphorus reached 88.3%, 69.2% and 59.7% resp. , but in the general pond their removal rate were only reached 48.0%, 43.4% and 22.8% resp. The effect of algae on the removal rate of TP was most obvious, that on COD was next and that on TN was weakest. The effect of aeration on the removal rate of the reducible substance with COD as the type was most, that on the decrease of TN was next and that on TP was weakest. The effect of sediment on the removal rate of

  5. Research for Developing Renewable Biofuels from Algae

    Energy Technology Data Exchange (ETDEWEB)

    Black, Paul N. [Univ. of Nebraska, Lincoln, NE (United States)

    2012-12-15

    Task A. Expansion of knowledge related to lipid production and secretion in algae A.1 Lipid biosynthesis in target algal species; Systems biology approaches are being used in combination with recent advances in Chlorella and Chlamydomonas genomics to address lipid accumulation in response to defined nutrient regimes. The UNL Algal Group continues screening additional species of Chlorella and other naturally occurring algae for those with optimal triglyceride production; Of the strains examined by the DOE's Aquatic Species Program, green algae, several species of Chlorella represent the largest group from which oleaginous candidates have been identified; A.1.1. Lipid profiling; Neutral lipid accumulation is routinely monitored by Nile red and BODIPY staining using high throughput strategies to screen for naturally occurring algae that accumulate triglyceride. These strategies complement those using spectrofluorometry to quantify lipid accumulation; Neutral lipid accumulation is routinely monitored by high performance thin-layer chromatography (HPTLC) and high performance liquid chromatography (HPLC) of lipid extracts in conjunction with; Carbon portioning experiments have been completed and the data currently are being analyzed and prepared for publication; Methods in the Black lab were developed to identify and quantify triacylglycerol (TAG), major membrane lipids [diacylglycerol trimethylhomoserine, phosphatidylethanolamine and chloroplast glycolipids], biosynthetic intermediates such as diacylglycerol, phosphatidic acid and lysophospholipids and different species of acyl-coenzyme A (acyl CoA).

  6. [Research status and prospect on hot water extract of Chlorella: the high value-added bioactive substance from Chlorella].

    Science.gov (United States)

    Zhuang, Xiuyuan; Huang, Yingming; Zhang, Daojing; Tao, Liming; Li, Yuanguang

    2015-01-01

    Chlorella is nutritious and has been used as a functional food much earlier than the other microalgae. C. pyrenoidosa, the potential microalgae which is currently cultured and developed for the new strategic industry of biofuels production and biological CO2 fixation, is a new resource food announced by the Ministry of Health of the People's Republic of China late 2012. Accumulation of high value-added substances in C. pyrenoidosa during the cultivation for lipid makes it possible to reduce the costs for C. pyrenoidosa-based biofuels production. Among these potential substances, hot water extract of Chlorella (CE), commercially known as "Chlorella growth factor", is the unique one that makes Chlorella more precious than the other algae, and the market price of CE is high. It is believed that CE is effective in growth promotion and immunoregulation. However, there is no systematic analysis on the research status of CE and its bioactivity. The present report summarized recent research progress of CE and its bioactivity. Generally, besides the main effect on immunoregulation and tumor inhibition, CE was efficient in improving metabolic syndrome, scavenging for free radicals, protecting against ultraviolet damage, chelating heavy metals, and protecting liver and bowel. Several major challenges in CE research as well as its prospects were also analysed in the present report.

  7. 螺旋藻和小球藻光藻反应器系统的建模仿真%Simulation Study on System Modeling of Spirulina and Chlorella in Light Algae Bioreactor

    Institute of Scientific and Technical Information of China (English)

    赵丽丽; 孙振天; 赵双双

    2016-01-01

    从航天员需求营养物质成分的角度,筛选了螺旋藻和小球藻在光藻反应器(Light Algae Bioreactor,LABR)中进行混合培养,运用MATLAB/Simulink软件建立了这两种微藻混合培养LABR的数学仿真模型.结果表明:当温度为30℃、光强为150μmol/(m2·s),螺旋藻和小球藻可以在LABR中较好的生长,获得总微藻生物量的最大值约为1.1 g/L.

  8. Effects of extraction systems on compositions of oil-extracted algae-residues from Chlorella phyrenoidosa%不同萃取体系对小球藻藻渣成分的影响

    Institute of Scientific and Technical Information of China (English)

    尹丰伟; 段珺; 高振; 郑洪立; 郑艳萍; 黄和

    2013-01-01

    考察5种萃取体系(A:正己烷,B:正己烷/乙醇,C:正己烷/异丙醇,D:氯仿/甲醇,E:氯仿/乙醇)对小球藻(Chlorella phyrenoidosa)油脂的提取效果及藻渣成分的影响.实验结果表明:不同的萃取体系下,油脂得率为D(12.27%)、E(8.87%)、C(7.71%)、B(6.80%)、A(3.91%),藻渣蛋白含量为A (52.60%)、E(46.23%)、B(40.19%)、C(39.52%)、D(32.52%),藻渣碳水化合物含量为A(23.28%)、E(16.15%)、B(13.24%)、D(13.50%)、C(9.06%);藻渣色素含量为A(1.75%)、E(1.29%)、B(1.14%)、C(0.96%)、D(0.58%);藻渣灰分含量为D(3.63%)、E(2.94%)、C(2.23%)、B(2.25%)、A(1.48%).综合考虑微藻生物柴油的生产及藻渣的可利用性,V(氯仿)/V(乙醇)=1是一种油脂萃取效果较好,藻渣营养成分损失较小的小球藻油脂萃取体系.

  9. Salivary Secretory Immunoglobulin a secretion increases after 4-weeks ingestion of chlorella-derived multicomponent supplement in humans: a randomized cross over study

    Directory of Open Access Journals (Sweden)

    Iemitsu Motoyuki

    2011-09-01

    Full Text Available Abstract Background Chlorella, a unicellular green alga that grows in fresh water, contains high levels of proteins, vitamins, minerals, and dietary fibers. Some studies have reported favorable immune function-related effects on biological secretions such as blood and breast milk in humans who have ingested a chlorella-derived multicomponent supplement. However, the effects of chlorella-derived supplement on mucosal immune functions remain unclear. The purpose of this study was to investigate whether chlorella ingestion increases the salivary secretory immunoglobulin A (SIgA secretion in humans using a blind, randomized, crossover study design. Methods Fifteen men took 30 placebo and 30 chlorella tablets per day for 4 weeks separated by a 12-week washout period. Before and after each trial, saliva samples were collected from a sterile cotton ball that was chewed after overnight fasting. Salivary SIgA concentrations were measured using ELISA. Results Compliance rates for placebo and chlorella ingestions were 97.0 ± 1.0% and 95.3 ± 1.6%, respectively. No difference was observed in salivary SIgA concentrations before and after placebo ingestion (P = 0.38. However, salivary SIgA concentrations were significantly elevated after chlorella ingestion compared to baseline (P P = 0.36, it significantly increased after 4-week chlorella ingestion than before intake (P Conclusions These results suggest 4-week ingestion of a chlorella-derived multicomponent supplement increases salivary SIgA secretion and possibly improves mucosal immune function in humans.

  10. Study of ecotoxicity of silver nanoparticles using algae

    Science.gov (United States)

    Kustov, L. M.; Abramenko, N. B.

    2016-11-01

    Silver nanoparticles have been prepared and tested for their ecotoxicity using Chlorella vulgaris Beijer. algae as a hydrobiotic test organism and a photometric method of control. The toxicity was supposed to originate from Ag+ ions released into the aqueous solution. Also, the toxicity of the stabilizing agent was found to be comparable to that of silver nanoparticles.

  11. Modeling and optimization of algae growth

    NARCIS (Netherlands)

    Thornton, Anthony Richard; Weinhart, Thomas; Bokhove, Onno; Zhang, Bowen; van der Sar, Dick M.; Kumar, Kundan; Pisarenco, Maxim; Rudnaya, Maria; Savceno, Valeriu; Rademacher, Jens; Zijlstra, Julia; Szabelska, Alicja; Zyprych, Joanna; van der Schans, Martin; Timperio, Vincent; Veerman, Frits; Frank, J.; van der Mei, R.; den Boer, A.; Bosman, J.; Bouman, N.; van Dam, S.; Verhoef, C.

    2010-01-01

    The wastewater from greenhouses has a high amount of mineral contamination and an environmentally-friendly method of removal is to use algae to clean this runo water. The algae consume the minerals as part of their growth process. In addition to cleaning the water, the created algal bio-mass has a

  12. Modeling and optimization of algae growth

    NARCIS (Netherlands)

    Thornton, Anthony Richard; Weinhart, Thomas; Bokhove, Onno; Zhang, Bowen; van der Sar, Dick M.; Kumar, Kundan; Pisarenco, Maxim; Rudnaya, Maria; Savcenco, Valeriu; Rademacher, Jens; Zijlstra, Julia; Szabelska, Alicja; Zyprych, Joanna; van der Schans, Martin; Timperio, Vincent; Veerman, Frits

    2010-01-01

    The wastewater from greenhouses has a high amount of mineral contamination and an environmentally-friendly method of removal is to use algae to clean this runoff water. The algae consume the minerals as part of their growth process. In addition to cleaning the water, the created algal bio-mass has a

  13. Modeling and optimization of algae growth

    NARCIS (Netherlands)

    Thornton, Anthony Richard; Weinhart, Thomas; Bokhove, Onno; Zhang, Bowen; van der Sar, Dick M.; Kumar, Kundan; Pisarenco, Maxim; Rudnaya, Maria; Savceno, Valeriu; Rademacher, Jens; Zijlstra, Julia; Szabelska, Alicja; Zyprych, Joanna; van der Schans, Martin; Timperio, Vincent; Veerman, Frits; Frank, J.; van der Mei, R.; den Boer, A.; Bosman, J.; Bouman, N.; van Dam, S.; Verhoef, C.

    2010-01-01

    The wastewater from greenhouses has a high amount of mineral contamination and an environmentally-friendly method of removal is to use algae to clean this runo water. The algae consume the minerals as part of their growth process. In addition to cleaning the water, the created algal bio-mass has a v

  14. Modeling and optimization of algae growth

    NARCIS (Netherlands)

    Thornton, Anthony; Weinhart, Thomas; Bokhove, Onno; Zhang, Bowen; Sar, van der Dick M.; Kumar, Kundan; Pisarenco, Maxim; Rudnaya, Maria; Savceno, Valeriu; Rademacher, Jens; Zijlstra, Julia; Szabelska, Alicja; Zyprych, Joanna; Schans, van der Martin; Timperio, Vincent; Veerman, Frits; Frank, J.; van der Mei, R.; den Boer, A.; Bosman, J.; Bouman, N.; van Dam, S.; Verhoef, C.

    2010-01-01

    The wastewater from greenhouses has a high amount of mineral contamination and an environmentally-friendly method of removal is to use algae to clean this runo water. The algae consume the minerals as part of their growth process. In addition to cleaning the water, the created algal bio-mass has a v

  15. Biodiesel production in crude oil contaminated environment using Chlorella vulgaris.

    Science.gov (United States)

    Xaaldi Kalhor, Aadel; Mohammadi Nassab, Adel Dabbagh; Abedi, Ehsan; Bahrami, Ahmad; Movafeghi, Ali

    2016-12-01

    Biodiesel is a valuable alternative to fossil fuels and many countries choose biodiesel as an unconventional energy source. A large number of investigations have been done on microalgae as a source of oil production. In recent years, wastewater pollutions have caused many ecological problems, and therefore, wastewater phycoremediation has attracted the international attention. This paper studied the cultivation of Chlorella vulgaris in a crude oil polluted environment for biodiesel production. Intended concentrations were 10 and 20gperliter (crude oil/water) at two times. The results showed that the growth of C. vulgaris was improved in wastewater and the maximum amount of dry mass and oil was produced at the highest concentration of crude oil (0.41g and 0.15g/l, respectively). In addition, dry mass and oil yield of the microalga were significantly enhanced by increasing the experiment duration.

  16. The Influence of Chlorella and Its Hot Water Extract Supplementation on Quality of Life in Patients with Breast Cancer

    Directory of Open Access Journals (Sweden)

    Naoto Noguchi

    2014-01-01

    Full Text Available A self-control, randomized, and open-label clinical trial was performed to test the effects of the unicellular green algae Chlorella and hot water extract supplementation on quality of life (QOL in patients with breast cancer. Forty-five female patients with breast cancer who were living at home and not hospitalized were randomly assigned to 3 groups receiving vitamin mix tablet (control, Chlorella granules (test food-1, or Chlorella extract drink (test food-2 daily for one month. The Functional Assessment of Cancer Therapy-Breast (FACT-B, the Izumo scale for abdominal symptom-specific QOL, and a narrative-form questionnaire were used to determine outcomes. Data of thirty-six subjects were included for final analysis. FACT-B scores at presupplementation found no significant group differences in all subscales. Scores on the breast cancer subscale in the Chlorella granule group significantly increased during the supplementation period (P=0.042. Fifty percent of the Chlorella extract group reported positive effects by the test food such as reduction of fatigue and improvements of dry skin (P<0.01 versus control group. The findings suggested the beneficial effects of Chlorella on breast cancer-related QOL and of Chlorella extract on vitality status in breast cancer patients. These findings need to be confirmed in a larger study.

  17. The influence of chlorella and its hot water extract supplementation on quality of life in patients with breast cancer.

    Science.gov (United States)

    Noguchi, Naoto; Maruyama, Isao; Yamada, Akira

    2014-01-01

    A self-control, randomized, and open-label clinical trial was performed to test the effects of the unicellular green algae Chlorella and hot water extract supplementation on quality of life (QOL) in patients with breast cancer. Forty-five female patients with breast cancer who were living at home and not hospitalized were randomly assigned to 3 groups receiving vitamin mix tablet (control), Chlorella granules (test food-1), or Chlorella extract drink (test food-2) daily for one month. The Functional Assessment of Cancer Therapy-Breast (FACT-B), the Izumo scale for abdominal symptom-specific QOL, and a narrative-form questionnaire were used to determine outcomes. Data of thirty-six subjects were included for final analysis. FACT-B scores at presupplementation found no significant group differences in all subscales. Scores on the breast cancer subscale in the Chlorella granule group significantly increased during the supplementation period (P = 0.042). Fifty percent of the Chlorella extract group reported positive effects by the test food such as reduction of fatigue and improvements of dry skin (P < 0.01 versus control group). The findings suggested the beneficial effects of Chlorella on breast cancer-related QOL and of Chlorella extract on vitality status in breast cancer patients. These findings need to be confirmed in a larger study.

  18. Effects of nickel and pH on the growth of Chlorella vulgaris

    Energy Technology Data Exchange (ETDEWEB)

    Lustigman, B.; Lee, L.H.; Khalil, A. [Montclair State College, Upper Montclair, NJ (United States)

    1995-07-01

    Chlorella is a spherical, unicellular, eukaryotic green algae. It is an obligate photoautotrophy containing chlorophylls a and b. It is a frequent symbiont of many other organisms such as paramecium, hydra and sponges and is important in fresh and marine environments, as well as in the soil. For these reasons, it has been suggested that Chlorella be used for metabolic studies as an indicator of environmental pollution. Ability of microorganisms to grow in environments containing high levels of toxic metals is frequently due to the organisms` capacity for adsorption of these ions and the role that they may play as essential cofactors in metalloenzymes as is the case for nickel. The purpose of this study was to determine the effect of nickel on the growth of Chlorella vulgaris. 19 refs., 4 figs., 1 tab.

  19. Bioprospecting of microalgae for integrated biomass production and phytoremediation of unsterilized wastewater and anaerobic digestion centrate.

    Science.gov (United States)

    Bohutskyi, Pavlo; Liu, Kexin; Nasr, Laila Khaled; Byers, Natalie; Rosenberg, Julian N; Oyler, George A; Betenbaugh, Michael J; Bouwer, Edward J

    2015-07-01

    Eighteen microalgae, including two local isolates, were evaluated for their ability to grow and remove nutrients from unsterilized primary or secondary wastewater effluents as well as wastewater supplemented with nutrient-rich anaerobic digester centrate (ADC). Most of the tested species except several phylogenetically clustered Chlorella sorokiniana including local isolates and Scenedesmus strains were unable to grow efficiently. This may reflect the presence of certain genetic traits important for robust growth in the unsterilized wastewater. The maximum algal-specific growth rates and biomass density obtained in these bacterial-contaminated cultures were in the range of 0.8-1 day(-1) and 250-350 mg L(-1), respectively. ADC supplementation was especially helpful to biologically treated secondary effluent with its lower initial macronutrient and micronutrient content. As a result of algal growth, total nitrogen and orthophosphate levels were reduced by as much as 90 and 70 %, respectively. Biological assimilation was estimated to be the main mechanism of nitrogen removal in primary and secondary effluents with ammonia volatilization and bacterial nitrification-denitrification contributing for cultures supplemented with ADC. Assimilation by algae served as the principal mechanism of orthophosphate remediation in secondary wastewater cultures, while chemical precipitation appeared also to be important for orthophosphate removal in primary wastewater. Overall, cultivation of microalgae in primary and primary + 5 % ADC may be more favorable from an economical and sustainability perspective due to elimination of the costly and energy-intensive biological treatment step. These findings demonstrate that unsterilized wastewater and ADC can serve as critical nutrient sources for biomass generation and that robust microalgae can be potent players in wastewater phytoremediation.

  20. Eradication of algae in ships' ballast water by electrolyzing

    Institute of Scientific and Technical Information of China (English)

    DANG Kun; SUN Pei-ting; XIAO Jing-kun; SONG Yong-xin

    2006-01-01

    In order to verify the effectiveness of electrolytic treatment on ships' ballast water,experiments are carried out by a pilot system in laboratory. The raw seawater and seawater with different concentrations of different algae are simulated as ships' ballast water. The algae in the raw seawater can be killed if it is treated by electrolysis with an initial residual chlorine concentration of 5 mg/L. If the seawater with one kind of algae (Nitzschia closterum, Dicrateria spp., or Pyramidomonnas sp.105cells/mL) is treated by electrolysis with an initial residual chlorine concentration of 5 mg/L, the alga can be sterilized. If the seawater with one kind of algae (Dunaliella sp., Platymonas or Chlorella spp.)is directly treated by electrolyzing with an initial residual chlorine concentration of 4 mg/L, the instant mortality changes with the concentration of different algae. However, after 72 hours, in all treated samples, there are no live algal cells found.

  1. [Effect of spectra on growth of chlorella and isochrysis].

    Science.gov (United States)

    Mao, An-Jun; Wang, Jing; Lin, Xue-Zheng; Meng, Ji-Wu

    2008-05-01

    Focusing on the speed and efficiency, the effects of different spectra on the growth of chlorella vulgaris and isochrysis galbana Parke 8701 were investigated by using monochromatic LED (light-emitting diode) and fluorescent lamp as light sources. It was concluded that continuous spectra accelerate the top-growth-rate, blue light has the best efficiency, and the combination of them can obtain a good balance of speed and efficiency. For the purpose of measuring spectra as a parameter of irradiation quantitatively, spectra-absorbability-coefficient defined as the quanta-absorbability- efficiency of spectra for algae was calculated by means of absorption spectra of algae and emission spectra of light sources. Compared with the experimental results the coefficients of different light sources have a positive correlation to their efficiency for growth, so the coefficient can be used to elementarily quantify the relation between the spectra and the efficiency for growth.

  2. Overall Energy Considerations for Algae Species Comparison and Selection in Algae-to-Fuels Processes

    Energy Technology Data Exchange (ETDEWEB)

    Link, D.; Kail, B.; Curtis, W.; Tuerk,A.

    2011-01-01

    The controlled growth of microalgae as a feedstock for alternative transportation fuel continues to receive much attention. Microalgae have the characteristics of rapid growth rate, high oil (lipid) content, and ability to be grown in unconventional scenarios. Algae have also been touted as beneficial for CO{sub 2} reuse, as algae can be grown using CO{sub 2} emissions from fossil-based energy generation. Moreover, algae does not compete in the food chain, lessening the 'food versus fuel' debate. Most often, it is assumed that either rapid production rate or high oii content should be the primary factor in algae selection for algae-to-fuels production systems. However, many important characteristics of algae growth and lipid production must be considered for species selection, growth condition, and scale-up. Under light limited, high density, photoautotrophic conditions, the inherent growth rate of an organism does not affect biomass productivity, carbon fixation rate, and energy fixation rate. However, the oil productivity is organism dependent, due to physiological differences in how the organisms allocate captured photons for growth and oil production and due to the differing conditions under which organisms accumulate oils. Therefore, many different factors must be considered when assessing the overall energy efficiency of fuel production for a given algae species. Two species, Chlorella vulgaris and Botryococcus braunii, are popular choices when discussing algae-to-fuels systems. Chlorella is a very robust species, often outcompeting other species in mixed-culture systems, and produces a lipid that is composed primarily of free fatty acids and glycerides. Botryococcus is regarded as a slower growing species, and the lipid that it produces is characterized by high hydrocarbon content, primarily C28-C34 botryococcenes. The difference in growth rates is often considered to be an advantage oiChlorella. However, the total energy captured by each algal

  3. Stability and loading properties of curcumin encapsulated in Chlorella vulgaris.

    Science.gov (United States)

    Jafari, Yaser; Sabahi, Hossein; Rahaie, Mahdi

    2016-11-15

    Curcumin (Cur), a polyphenols with pharmacological function, was successfully encapsulated in algae (Alg) cell (Chlorella vulgaris) as confirmed by fluorescence microscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and Fourier transform-infrared spectroscopy (FT-IR). Fluorescence micrographs, TGA, DSC and FTIR spectra suggested the hypothesis inclusion Cur in Nano-empty spaces inside cell wall of Alg. The TGA analysis showed that the thermal stability of Alg and Cur at algae/curcumin complex was 3.8% and 33% higher than their free forms at 0-300°C and 300-600°C ranges, respectively. After encapsulation in Alg cells, the photostability of Cur was enhanced by about 2.5-fold. Adsorption isotherm of Cur into Alg was fitted with the Freundlich isotherm. The microcapsules were loaded with Cur up to about 55% w/w which is much higher than other reported bio-carriers. In conclusion, the data proved that Chlorella vulgaris cell can be used as a new stable carrier for Cur.

  4. The culture of Chlorella vulgaris with human urine in multibiological life support system experiments

    Science.gov (United States)

    Li, Ming; Liu, Hong; Tong, Ling; Fu, Yuming; He, Wenting; Hu, Enzhu; Hu, Dawei

    The Integrative Experimental System (IES) was established as a tool to evaluate the rela-tionship of the subsystems in Bioregenerative Life Support System, and Multibiological Life Support System Experiments (MLSSE) have been conducted in the IES. The IES consists of a higher plant chamber, an animal chamber and a plate photo bioreactor (PPB) which cultivated lettuce (Lactuca sativa L.), silkworm (Bombyx Mori L.) and microalgae (Chlorella vulgaris), respectively. In MLSSE, four volunteers took turns breathing the system air through a tube connected with the animal chamber periodically. According to the CO2 concentration in the IES, the automotive control system of the PPB changed the light intensity regulating the photosynthesis of Chlorella vulgaris to make CO2 /O2 in the system maintain at stable levels. Chlorella vulgaris grew with human urine by carrying certain amount of alga liquid out of the bioreactor every day with synthetic urine replenished into the system, and O2 was regenerated, at the same time human urine was purified. Results showed that this IES worked stably and Chlorella vulgaris grew well; The culture of Chlorella vulgaris could be used to keep the balance of CO2 and O2 , and the change of light intensity could control the gas composition in the IES; Microalgae culture could be used in emergency in the system, the culture of Chlorella vulgaris could recover to original state in 5 days; 15.6 ml of condensation water was obtained every day by the culture of Chlorella vulgaris; The removal efficiencies of N, P in human urine could reach to 98.2% and 99.5%.

  5. Chlorella intake attenuates reduced salivary SIgA secretion in kendo training camp participants

    Directory of Open Access Journals (Sweden)

    Otsuki Takeshi

    2012-12-01

    Full Text Available Abstract Background The green alga Chlorella contains high levels of proteins, vitamins, and minerals. We previously reported that a chlorella-derived multicomponent supplement increased the secretion rate of salivary secretory immunoglobulin A (SIgA in humans. Here, we investigated whether intake of this chlorella-derived supplement attenuated the reduced salivary SIgA secretion rate during a kendo training camp. Methods Ten female kendo athletes participated in inter-university 6-day spring and 4-day summer camps. They were randomized into two groups; one took placebo tablets during the spring camp and chlorella tablets during the summer camp, while the other took chlorella tablets during the spring camp and placebo tablets during the summer camp. Subjects took these tablets starting 4 weeks before the camp until post-camp saliva sampling. Salivary SIgA concentrations were measured by ELISA. Results All subjects participated in nearly all training programs, and body-mass changes and subjective physical well-being scores during the camps were comparable between the groups. However, salivary SIgA secretion rate changes were different between these groups. Salivary SIgA secretion rates decreased during the camp in the placebo group (before vs. second, middle, and final day of camp, and after the camp: 146 ± 89 vs. 87 ± 56, 70 ± 45, 94 ± 58, and 116 ± 71 μg/min, whereas no such decreases were observed in the chlorella group (121 ± 53 vs. 113 ± 68, 98 ± 69,115 ± 80, and 128 ± 59 μg/min. Conclusion Our results suggest that a use of a chlorella-derived dietary supplement attenuates reduced salivary SIgA secretion during a training camp for a competitive sport.

  6. PENGGUNAAN MEMBRAN SERAT BERONGGA SEBAGAI AERATOR DALAM SISTEM KULTIVASI UNTUK MENINGKATKAN PRODUKSI BIOMASSA DAN BIOFIKSASI CO2 DARI Chlorella vulgaris

    Directory of Open Access Journals (Sweden)

    D Dianursanti

    2015-06-01

    Full Text Available Pemanasan global yang memicu terjadinya perubahan iklim, sebagian besar disebabkan karena merebaknya gas CO2.  Pemanfaatan mikroalga Chlorella sp. untuk mereduksi gas CO2 menjadi potensi yang menjanjikan. Hal ini mengingat, bahwa Chlorella dapat dengan efisien mereduksi CO2 karena mereka dapat tumbuh dengan cepat dan mudah diadaptasikan ke dalam rekayasa sistem fotobioreaktor. Dalam penelitian ini akan diupayakan pengaturan sistem aerasi berfilter untuk kultivasi Chlorella vulgaris dalam reaktor agar proses transfer massa gas CO2 dalam kultur mikroalga menjadi lebih baik. Dengan demikian nilai KLa (CO2 menjadi salah satu parameter penentu dalam peningkatan produksi biomassa Chlorella. Nilai KLa yang tinggi menunjukkan proses transfer massa CO2 yang lebih baik dalam kultur mikroalga. Namun nilai KLa (CO2 yang terlalu besar sangat mungkin menyebabkan terjadinya shear stress pada alga.Dengan menggunakan membran serat berongga sebagai aerator, permasalahan shear stress pada alga dapat dihindari. Dengan diameter pori yang sangat kecil, membran ini dapat memberikan laju alir dan transfer massa CO2 dalam kultur yang optimal, tanpa menimbulkan efek shear strees. Dengan demikian penggunaan membran ini dapat menghasilkan produktivitas Chlorella yang lebih baik serta dapat meningkatkan kemampuan biofiksasi CO2 selama proses kultivasinya. Penggunaan membran serat berongga sebagai aerator telah terbukti mampu meningkatkan produksi biomassa C. vulgaris  sebesar 27,2 %. Abstract Global warming triggering climate change is largely due to the presence of CO2. Utilization of microalgae Chlorella vulgaris to reduce CO2 gas is potential as it efficiently reduces CO2while growing quickly and adapting to the photobioreactor systems engineering. This study explored filter aeration system settings for cultivating C. vulgaris in the reactor thus mass transfer of CO2 in microalgae cultures becomes more efficient. Value of KLa (CO2 is one of the parameters in

  7. [Effect of magnesium deficiency on photosynthetic physiology and triacylglyceride (TAG) accumulation of Chlorella vulgaris].

    Science.gov (United States)

    Wang, Shan; Zhao, Shu-Xin; Wei, Chang-Long; Yu, Shui-Yan; Shi, Ji-Ping; Zhang, Bao-Guo

    2014-04-01

    As an excellent biological resource, Chlorella has wide applications for production of biofuel, bioactive substances and water environment restoration. Therefore, it is very important to understand the photosynthetic physiology characteristics of Chlorella. Magnesium ions play an important role in the growth of microalgae, not only the central atom of chlorophyll, but also the cofactor of some key enzyme in the metabolic pathway. A laboratory study was conducted to evaluate the effects of magnesium deficiency on several photosynthetic and physiological parameters and the triacylglyceride (TAG) accumulation of the green alga, Chlorella vulgaris, in the photoautotrophic culture process. Chlorella vulgaris biomass, protein, chlorophyll a and chlorophyll b contents decreased by 20%, 43.96%, 27.52% and 28.07% in response to magnesium deficiency, while the total oil content increased by 19.60%. Moreover, magnesium deficiency decreased the maximal photochemical efficiency F(v)/F(m) by 22.54%, but increased the non-photochemical quenching parameters qN. Our results indicated the decline of chlorophyll caused by magnesium, which affected the photosynthesis efficiency, lead to the growth inhibition of Chlorella vulgaris and affected the protein synthesis and increased the triacylglyceride (TAG) accumulation.

  8. Electrical performance of distribution insulators with chlorella vulgaris growth on its surface

    Directory of Open Access Journals (Sweden)

    H. E. Rojas

    2015-11-01

    Full Text Available This paper presents a study about electrical performance of ceramic and polymeric insulators bio-contaminated with alga Chlorella vulgaris. The performed tests involve ANSI 55-2 and ANSI 52-1 ceramic insulators and ANSI DS-15 polymeric insulators, all of them used in distribution systems of Colombia. Biological contamination of insulators is realized using a controlled environment chamber that adjusts the temperature, humidity and light radiation. The laboratory tests include measurements of flashover voltages and leakage currents and they were performed to determine how insulators are affected by biological contamination. After a series of laboratory tests, it was concluded that the presence of Chlorella vulgaris on the contaminated ceramic insulators reduces the wet flashover voltage up to 12% and increases their leakage currents up to 80%. On the other hand, for polymeric insulators the effect of algae growth on flashover voltages was not to strong, although the leakage currents increase up to 60%.

  9. Cloning and Characterization of the -Carotene Desaturase Gene from Chlorella protothecoides CS-41

    Directory of Open Access Journals (Sweden)

    Meiya Li

    2011-01-01

    Full Text Available To elucidate the lutein biosynthesis pathway in the lutein-producing alga, Chlorella protothecoides CS-41, the -carotene desaturase gene (zds was isolated from Chlorella protothecoides using the approach of rapid amplification of cDNA ends. The full-length cDNA sequence was 2031 bp and contained 1755 bp putative open reading frame which encodes a 584 amino acid deduced polypeptide whose computed molecular weight was 63.7 kDa. Sequence homology research indicated that the nucleotide and putative protein had sequence identities of 72.5% and 69.5% with those of the green alga Chlamydomonas reinhardtii, respectively. Phylogenetic analysis demonstrated that the ZDS from C. protothecoides CS-41 had a closer relationship with those of chlorophyta and higher plants than with those of other species. In addition, we also found that the zds gene expression was upregulated in response to light.

  10. Potential use of duckweed based anaerobic digester effluent as a feed source for heterotrophic growth of micro-algae

    Science.gov (United States)

    Ahmadi, L.; Dupont, R.

    2013-12-01

    Finding an alternative source of energy for the growing world's demand is a challenging task being considered by many scientists. Various types of renewable energy alternatives are being investigated by researchers around the world. The abundance of duckweed (i.e., Lemna and Wolfia sp.) in wetlands and wastewater lagoons, their rapid growth, and their capacity for nutrient, metal and other contaminant removal from wastewater suggests their potential as an inexpensive source of biomass for biofuel production. Another source of biomass for biofuel and energy production is micro-algae. The large-scale growth of micro-algae can potentially be achieved in a smaller footprint and at a higher rate and lower cost via heterotrophic growth compared to autotrophic growth for specific species that can grow under both conditions. Here we describe two types of research. First, two lab-scale, 5 L anaerobic digesters containing municipal raw wastewater that were set up, maintained and monitored over the course of 6 months using duckweed as the feed source. The pH, salinity, amount of gas production and gas composition were measured on a daily basis. The results from these measurements show that duckweed can be used as a good source of biofuel production in the form of methane gas. The second set of reactors consisted of two 1 L batch fed reactors containing algae (Chlorella vulgaris) grown in the lab environment heterotrophically. The pH and DO were monitored on a daily basis in order to investigate their effect on algae growth. Lipid analysis of the harvested algal biomass was done to investigate the efficiency of harvestable biofuel products. A nutrient solution containing glucose as an energy source was used as the initial feed solution, and the potential substitution of the glucose solution with the organic carbon residue from the duckweed digester effluent was investigated. Methane production, carbon stabilization, and gas composition results from the duckweed fed anaerobic

  11. Using oxidized liquid and solid human waste as nutrients for Chlorella vulgaris and cyanobacterium Oscillatoria deflexa

    Science.gov (United States)

    Trifonov, Sergey V.; Kalacheva, Galina; Tirranen, Lyalya; Gribovskaya, Iliada

    At stationary terrestrial and space stations with closed and partially closed substance exchange not only plants, but also algae can regenerate atmosphere. Their biomass can be used for feeding Daphnia and Moina species, which, in their turn, serve as food for fish. In addition, it is possible to use algae for production of biological fuel. We suggested two methods of human waste mineralization: dry (evaporation with subsequent incineration in a muffle furnace) and wet (oxidation in a reactor using hydrogen peroxide). The research task was to prepare nutrient media for green alga Chlorella vulgaris and cyanobacterium Oscillatoria deflexa using liquid human waste mineralized by dry method, and to prepare media for chlorella on the basis of 1) liquid and 2) liquid and solid human waste mineralized by wet method. The algae were grown in batch culture in a climate chamber with the following parameters: illumination 7 klx, temperature 27-30 (°) C, culture density 1-2 g/l of dry weight. The control for chlorella was Tamiya medium, pH-5, and for oscillstoria — Zarrouk medium, pH-10. Maximum permissible concentrations of NaCl, Cl, urea (NH _{2}) _{2}CO, and native urine were established for algae. Missing ingredients (such as salts and acids) for experimental nutrient media were determined: their addition made it possible to obtain the biomass production not less than that in the control. The estimation was given of the mineral and biochemical composition of algae grown on experimental media. Microbiological test revealed absence of foreign microbial flora in experimental cultures.

  12. [Study of the growth and development of Chlorella on "Kosmos-1887"].

    Science.gov (United States)

    Sychev, V N; Levinskikh, M A; Livanskaia, O G

    1989-01-01

    The growth, development and population characteristics of Chlorella cells flown for 13 days in space were investigated during their postflight cultivation. The growth rate of flown algae did not differ from that of ground-based controls in terms of increases in the cell number and biomass. All basic parameters of the specimens (generation time, number of developing autospores, time ratio of developmental phases) were ontogentically normal. Exposure of the algae to space flight as a component of the algobacterial cenosis--fish autotrophic-heterotrophic system produced no significant effect of the population or individual specimens during their postflight cultivation.

  13. Investigating the feasibility of growing algae for fuel in Southern nevada

    Science.gov (United States)

    Moazeni, Faegheh

    Microalgae capable of growing in waste are adequate to be mass-cultivated for biodiesel, avoiding fertilizers and clean water, two obstacles to sustainability of the feedstock production. This study replaces fertilizers and clean water with waste products. The investigated wastes include (1) the liquid fraction of sewage after solids and particles are removed, known as centrate, and (2) algal biomass residue, i.e. the algae remaining at the end of the lipids extraction process at biofuel plants. These wastes contain sufficient amount of nitrogen and phosphorus required for algal growth. This study proposes a system in which centrate would be used as an initial source of water and nutrients for microalgal growth. The generated biomass waste can be continuously recycled, serving as a fertilizer. If so desired, the centrate can be reverted back into the system from time to time as a nutrition supplement and as a make-up water source, particularly in open ponds that face evaporation. Of the six studied algae, i.e. Chlorella sorokiniana, Encyonema caespitosum, Nitzschia thermalis, Scenedesmus sp., Synechocystis sp., and Limnothrix sp., mostly isolated from the habitats influenced by municipal wastewater in and around the Las Vegas Valley, two green algae were eligible. In the laboratory, the green algae C. sorokiniana and Scenedesmus sp. grew in the media composed of centrate or algal residue faster than in the mineral medium BG11, optimized for algal growth. The enhanced productivity is mainly attributed to the photosynthesis known for mixotrophic process and the presence of organic carbon in the waste which serves as an extra source of energy. Tolerance for hard water and strong light and, in the case of C. sorokiniana , an unusually high optimum temperature between 32 and 35°C are also attributing factors to the enhanced productivity of algae. These studied species are particularly suited for cultivation in their native southwestern United States, particularly

  14. Physiological and biochemical responses of Chlorella vulgaris to Congo red.

    Science.gov (United States)

    Hernández-Zamora, Miriam; Perales-Vela, Hugo Virgilio; Flores-Ortíz, César Mateo; Cañizares-Villanueva, Rosa Olivia

    2014-10-01

    Extensive use of synthetic dyes in many industrial applications releases large volumes of wastewater. Wastewaters from dying industries are considered hazardous and require careful treatment prior to discharge into receiving water bodies. Dyes can affect photosynthetic activities of aquatic flora and decrease dissolved oxygen in water. The aim of this study was to evaluate the effect of Congo red on growth and metabolic activity of Chlorella vulgaris after 96h exposure. Exposure of the microalga to Congo red reduced growth rate, photosynthesis and respiration. Analysis of chlorophyll a fluorescence emission showed that the donor side of photosystem II was affected at high concentrations of Congo red. The quantum yield for electron transport (φEo), the electron transport rate (ETR) and the performance index (PI) also decreased. The reduction in the ability to absorb and use the quantum energy increased non-photochemical (NPQ) mechanisms for thermal dissipation. Overall, Congo red affects growth and metabolic activity in photosynthetic organisms in aquatic environments.

  15. Enzymatic and non-enzymatic antioxidant potentials of Chlorella vulgaris grown in effluent of a confectionery industry

    OpenAIRE

    2011-01-01

    Enzymatic and non-enzymatic antioxidant potentials of Chlorella vulgaris have gained considerable importance in recent decades. C. vulgaris strain highly tolerant to extreme pH variations was isolated and mass-cultivated in the wastewater from a confectionery industry. C.vulgaris showed better growth in wastewater than in improvised CFTRI medium. The microalgal biomass was then screened for the following antioxidants: peroxidase, superoxide dismutase, polyphenol oxidase, glutathione peroxidas...

  16. Light respiration in Chlorella sorokiniana

    NARCIS (Netherlands)

    Kliphuis, A.M.J.; Janssen, M.G.J.; End, van den E.J.; Martens, D.E.; Wijffels, R.H.

    2011-01-01

    Respiration and photosynthesis are two important processes in microalgal growth that occur simultaneously in the light. To know the rates of both processes, at least one of them has to be measured. To be able to measure the rate of light respiration of Chlorella sorokiniana, the measurement of oxyge

  17. Nitrogen and phosphorus removal from cyanobacteria-swine manure wastewater by Chlorella vulgaris C9-JN2010%利用Chlorella vulgaris C9-JN2010去除蓝藻-猪粪沼液废水中氮磷的研究

    Institute of Scientific and Technical Information of China (English)

    程露萍; 李昌灵; 张梦; 李宇佶; 杨海麟; 张玲

    2014-01-01

    利用普通小球藻Chlorella vugaris C9-JN2010处理蓝藻-猪粪沼液废水,以实现废水无害化利用.实验考察了氮磷比和沼液浓度对小球藻生长及处理废水效果的影响,结果表明:在氮磷比(20∶1)和沼液浓度(5%)条件下培养小球藻,藻细胞生长和废水处理效果最佳,最高细胞干重及生产强度分别为900.1 mg·L-1和85.1 mg·L-1·d-1,废水中总氮、总磷、氨氮的去除率分别为84.6%、95.9%和90.5%,对应去除强度分别为5.43 mg·L-1·d-1、0.30 mg·L-1·d-1和4.75 mg·L-1·d-1.利用小球藻可较彻底的去除蓝藻-猪粪沼液废水中氮、磷等营养,达到污水处理效果.

  18. Antioxidant activity of the microalga Chlorella vulgaris cultered on special conditions.

    Science.gov (United States)

    Miranda, M S; Sato, S; Mancini-Filho, J

    2001-01-01

    The chemical composition of Chlorella vulgaris indicates that it has a high nutritional value to a wide range of essential nutrients, such as vitamins, minerals and proteins. Moreover, it contains other compounds such as n-3 and n-6 polynsaturated fatty acids, provitamins and phenolic compounds. In addition, this alga can be produced in large-scale systems. The objective of the present study was to evaluate the antioxidant capacity of a Chlorella cultured on three differents temperatures (15 degrees C, 20 degrees C and 30 degrees C) in 3 Klux. Chlorella cultured samples were submitted to sequential extration using as solvents: ether, methanol and water. The antioxidant activity in the extracts was measured by b-carotene/linoleic acid system, at 50 degrees C and absorbances reading at 470 nm. One control with BHT, 100 ppm was used in this determination. The total phenolic compounds was determined with Folin-Ciocalteu reagent using the spectrophotometric measured at 780 nm with catechin as standard. The phenolic acid analysis were carried out using gas chromatograph equipped with a capillary column and flame ionization detector. Non conjugated and total phenolic acids were identified on the basis of the relative retention time of their derivatives compared with the standard phenolic acids. The methanolic extract from Chlorella cultured at 30 degrees C showed higher antioxidant activity (85%) quite similar of BHT (86%). By the Rancimat test (lipidic medium) two fractions from methanolic extracts showed too higher antioxidant activity with induction times > 37.50 h at 60 degrees C and 11.5 h at 100 degrees C. The total phenolic compounds were 24.95 mg in 1 g of dry alga matter from methanolic extract and five phenolic acids were identified. The phenolic compounds salicylic, trans cinnamic, synaptic, chlorogenic, chimic and caffeic acids found in the methanolic Chlorella extract may be responsible for its higher antioxidant activity.

  19. Algae inhibition experiment and load characteristics of the algae solution

    Science.gov (United States)

    Xiong, L.; Gao, J. X.; Zhang, Y. X.; Yang, Z. K.; Zhang, D. Q.; He, W.

    2016-08-01

    It is necessary to inhibit microbial growth in an industrial cooling water system. This paper has developed a Monopolar/Bipolar polarity high voltage pulser with load adaptability for an algal experimental study. The load characteristics of the Chlorella pyrenoidosa solution were examined, and it was found that the solution load is resistive. The resistance is related to the plate area, concentration, and temperature of the solution. Furthermore, the pulser's treatment actually inhibits the algae cell growth. This article also explores the influence of various parameters of electric pulses on the algal effect. After the experiment, the optimum pulse parameters were determined to be an electric field intensity of 750 V/cm, a pulse width per second of 120μs, and monopolar polarity.

  20. Effects of different substrates in the mitigation of algae-induced high pH wastewaters in a pilot-scale free water surface wetland system.

    Science.gov (United States)

    Jin, Meng; Champagne, Pascale; Hall, Geoffrey

    2017-01-01

    Waste stabilization ponds (WSPs), as part of municipal wastewater treatment strategies, can exhibit variability in performance due to climatic conditions. Under elevated temperature and strong solar radiation, algal blooms and subsequent high pH effluents have often been observed. In this study, four substrates (gravel, peat, organic mulch, and topsoil) were evaluated for their ability to attenuate high pH effluents from a WSP. Synthetic wastewater with pH > 9.5, and low organic and nutrient loadings, was used to mimic algal-induced high pH effluents in 72 L rectangular bench-scale superficial constructed wetland configuration reactors. Peat exhibited the highest attenuation ability, where the effluent pH decreased substantially from 10.3 to 7.7, primarily due to its high organic contents. Peat also removed 53.7% of the influent total phosphorus, which could effectively limit algal growth. No statistically significant differences were discovered among gravel, topsoil, and organic mulch in terms of pH attenuation. Topsoil and organic mulch both have a relatively high alkalinity, making them ideal to maintain consistent pH levels. However, naturally high chemical oxygen demand levels in organic mulch raised concerns in the leaching of these compounds into the treated wastewater, making it less appealing for systems with low organic loading.

  1. Water Purification Research on Cultivation of Chlorella vulgaris with Industrial Wastewater%利用工业废水培养小球藻的水质净化研究

    Institute of Scientific and Technical Information of China (English)

    周连宁; 王波

    2013-01-01

    [目的]考察利用工业废水规模化培养高脂微藻生产生物柴油,同时净化废水.[方法]采用豆制品废水、啤酒废水、肉制品废水作为小球藻(Chlorella vulgaris)生长的培养液,比较不同废水营养因子及培养条件对小球藻生长与油脂累积的影响.[结果]豆制品废水与啤酒废水能较好的促进小球藻的生长,当废水中Mg2+和无机磷的添加量分别为112.5 mg/L、60 mg/L时,小球藻的干重达到最大3.57g/L、4.44 g/L,且小球藻适于生长在中性中温、5 000 lx光照务件下,培养过程中可适量通入空气以补充碳源;在最适条件下培养结束后废水的CODcr、TN和TP去除率分别能达到72.9% ~85.1%、37.9% ~ 64.2%和30.1% ~84.9%.[结论]小球藻具有典型的氮磷去除能力.

  2. 小球藻Chlorella sorokiniana C74营养素分析%Nutrient Analysis of Chlorella sorokiniana C74

    Institute of Scientific and Technical Information of China (English)

    张玲; 刘平怀; 罗宁; 陈晨; 何沂飞; 李昂

    2016-01-01

    测定小球藻Chlorella sorokiniana C74营养成分,为其综合利用提供依据。结果显示,Chlorella sorokiniana C74含有丰富的营养物质,粗蛋白、多糖、油脂、灰分、粗纤维和色素分别占藻粉干重的20.4%、34.28%、22.16%、12.20%、20.22%和4.50%。脂肪酸分析显示Chlorella sorokiniana C74中含有多种不饱和脂肪酸,其中亚油酸和亚麻酸含量分别为22.73%和14.87%;氨基酸含量为17.50%,其中必需氨基酸为6.17%,通过必需氨基酸指数评价,说明Chlorella sorokiniana C74是一种优质的蛋白来源;维生素含量丰富,尤其是维生素B1、B3和B6;藻粉含有多种矿物质元素,其中钾、镁、钙、铁和锌5种元素含量较高,重金属铅、汞、砷和镉含量均未超标。%Determination of Chlorella sorokiniana C74 nutrients, the results showed that Chlorella sorokiniana C74 contains kinds of nutrients, crude protein, carbohydrates, fat, ash, crude fiber and pigment was account-ed for 20.4%, 34.28%, 22.16%, 12.20%, 20.22%and 4.50%by algae powder dry weight respectively. Fatty acid analysis showed that algae powder contains a variety of unsaturated fatty acids, and linoleic acid and linolenic acid contents were 22.73 % and 14.87%. Contents of amino acid in Chlorella sorokiniana C74 was 17.50%, of which the essential amino acids was 6.17%. Through essential amino acid index evaluation, indi-cating that Chlorella sorokiniana C74 was an excellent source of protein;Chlorella sorokiniana C74 was rich in vitamins, especially vitamin B1, B3 and B6. Algae powder contains a variety of trace mineral elements, and potassium, magnesium, calcium, iron and zinc was higher, the heavy metal lead, mercury, arsenic and cad-mium was no more than the national standard.

  3. Optimization of simultaneous biomass production and nutrient removal by mixotrophic Chlorella sp. using response surface methodology.

    Science.gov (United States)

    Lee, Yu-Ru; Chen, Jen-Jeng

    2016-01-01

    The bioprospecting of potentially mixotrophic microalgae in a constructed wetland was conducted. A locally isolated microalga, Chlorella sp., was grown to determine the effect of temperature, aeration rate, and cultivation time on simultaneous biomass production and nutrient removal from piggery wastewater using central composite design (CCD). The most important variable for the biomass productivity of Chlorella sp. was aeration rate, while that for lipid content and nutrient removal efficiency was cultivation time. Total nitrogen (TN) and total phosphorus (TP) removal efficiencies were higher than that of chemical oxygen demand (COD) from piggery wastewater. The CCD results indicate that the highest biomass productivity (79.2 mg L(-1) d(-1)) and simultaneous nutrient removal efficiency (TN 80.9%, TP 99.2%, COD 74.5%) were obtained with a cultivation temperature of 25 °C, a cultivation time of 5 days, and an air aeration rate of 1.6 L L(-1) min(-1). Palmitic acid (C16:0) and linoleic acid (C18:2) were both abundant in Chlorella sp. cells under mixotrophic cultivation with piggery wastewater.

  4. Potential Health Effects of Enzymatic Protein Hydrolysates from Chlorella vulgaris

    Directory of Open Access Journals (Sweden)

    Mahsa Sedighi

    2016-06-01

    Full Text Available Background and Objective: Chlorella vulgaris is a multi-cellular edible algal species with abundant proteins. Extraction of high value protein fractions for pharmaceutical and nutritional applications can significantly increase the commercial value of microalga biomasses. There is no known report on the anticancer peptides derived from the Chlorella vulgaris abundant protein.Materials and Methods: This study examined the antimicrobial and anticancer effects of peptides from a hydrolyzed Chlorella vulgaris protein with 62 kDa molecular weight. Protein hydrolysis was done by pepsin as a gastrointestinal protease, and was monitored through protein content measurement, sodium dodecyl sulfate polyacrylamide gel electrophoresis, and high performance liquidchromatography measurements. Inhibitory effect of the produced peptides on Escherichia coli cells and breast cancer cell lines was assayed.Results and Conclusion: Hydrolyzed peptides induced a decrease of about 34.1% in the growth of Escherichia coli, and the peptides of 3 to 5 kDa molecular weight had strong impact on the viability of breast cancer cells with IC50 value of 50 μg μl-1. The peptide fractions demonstrating antimicrobial and anti-cancer activities have the potential for use as functional food ingredients for health benefits. These results demonstrate that inexpensive algae proteinscould be a new alternative to produce anticancer peptides.Conflict of interest: The authors declare that there is no conflict of interest.

  5. Environmental life cycle comparison of algae to other bioenergy feedstocks.

    Science.gov (United States)

    Clarens, Andres F; Resurreccion, Eleazer P; White, Mark A; Colosi, Lisa M

    2010-03-01

    Algae are an attractive source of biomass energy since they do not compete with food crops and have higher energy yields per area than terrestrial crops. In spite of these advantages, algae cultivation has not yet been compared with conventional crops from a life cycle perspective. In this work, the impacts associated with algae production were determined using a stochastic life cycle model and compared with switchgrass, canola, and corn farming. The results indicate that these conventional crops have lower environmental impacts than algae in energy use, greenhouse gas emissions, and water regardless of cultivation location. Only in total land use and eutrophication potential do algae perform favorably. The large environmental footprint of algae cultivation is driven predominantly by upstream impacts, such as the demand for CO(2) and fertilizer. To reduce these impacts, flue gas and, to a greater extent, wastewater could be used to offset most of the environmental burdens associated with algae. To demonstrate the benefits of algae production coupled with wastewater treatment, the model was expanded to include three different municipal wastewater effluents as sources of nitrogen and phosphorus. Each provided a significant reduction in the burdens of algae cultivation, and the use of source-separated urine was found to make algae more environmentally beneficial than the terrestrial crops.

  6. Acidophilic algae isolated from mine-impacted environments and their roles in sustaining heterotrophic acidophiles

    Directory of Open Access Journals (Sweden)

    David Barrie Johnson

    2012-09-01

    Full Text Available Two acidophilic algae, identified as strains of Chlorella protothecoides var. acidicola and Euglena mutabilis, were isolated in pure culture from abandoned copper mines in Spain and Wales and grown in pH- and temperature-controlled bioreactors. The Chlorella isolate grew optimally at pH 2.5 and 30 ˚C, with a corresponding culture doubling time of 9 hours. The isolates displayed similar tolerance (10-50 mM to four transition metals tested. Growth of the algae in liquid media was paralleled with increasing concentrations of dissolved organic carbon (DOC. Glycolic acid was identified as a significant component (12- 14% of total DOC. Protracted incubation resulted in concentrations of glycolic acid declining in both cases, and glycolic acid added to a culture of Chlorella incubated in the dark was taken up by the alga (~100% within three days. Two monosaccharides were identified in cell-free liquors of each algal isolate: fructose and glucose (Chlorella, and mannitol and glucose (Euglena. These were rapidly metabolised by acidophilic heterotrophic bacteria (Acidiphilium and Acidobacterium spp. though only fructose was utilised by the more fastidious heterotroph Acidocella aromatica. The significance of algae in promoting the growth of iron- (and sulfate- reducing heterotrophic acidophiles that are important in remediating mine-impacted waters is discussed.

  7. The Chlorella variabilis NC64A Genome Reveals Adaptation to Photosymbiosis, Coevolution with Viruses, and Cryptic Sex

    Energy Technology Data Exchange (ETDEWEB)

    Blanc, Guillaume; Duncan, Garry A.; Agarakova, Irina; Borodovsky, Mark; Gurnon, James; Kuo, Alan; Lindquist, Erika; Lucas, Susan; Pangailinan, Jasmyn; Polle, Juergen; Salamov, Asaf; Terry, Astrid; Yamada, Takashi; Dunigan, David D.; Grigoriev, Igor V.; Claverie, Jean-Michel; Etten, James L. Van

    2010-05-06

    Chlorella variabilis NC64A, a unicellular photosynthetic green alga (Trebouxiophyceae), is an intracellular photobiont of Paramecium bursaria and a model system for studying virus/algal interactions. We sequenced its 46-Mb nuclear genome, revealing an expansion of protein families that could have participated in adaptation to symbiosis. NC64A exhibits variations in GC content across its genome that correlate with global expression level, average intron size, and codon usage bias. Although Chlorella species have been assumed to be asexual and nonmotile, the NC64A genome encodes all the known meiosis-specific proteins and a subset of proteins found in flagella. We hypothesize that Chlorella might have retained a flagella-derived structure that could be involved in sexual reproduction. Furthermore, a survey of phytohormone pathways in chlorophyte algae identified algal orthologs of Arabidopsis thaliana genes involved in hormone biosynthesis and signaling, suggesting that these functions were established prior to the evolution of land plants. We show that the ability of Chlorella to produce chitinous cell walls likely resulted from the capture of metabolic genes by horizontal gene transfer from algal viruses, prokaryotes, or fungi. Analysis of the NC64A genome substantially advances our understanding of the green lineage evolution, including the genomic interplay with viruses and symbiosis between eukaryotes.

  8. Use of De Novo Transcriptome Libraries to Characterize a Novel Oleaginous Marine Chlorella Species during the Accumulation of Triacylglycerols.

    Directory of Open Access Journals (Sweden)

    Cresten B Mansfeldt

    Full Text Available Marine chlorophytes of the genus Chlorella are unicellular algae capable of accumulating a high proportion of cellular lipids that can be used for biodiesel production. In this study, we examined the broad physiological capabilities of a subtropical strain (C596 of Chlorella sp. "SAG-211-18" including its heterotrophic growth and tolerance to low salt. We found that the alga replicates more slowly at diluted salt concentrations and can grow on a wide range of carbon substrates in the dark. We then sequenced the RNA of Chlorella strain C596 to elucidate key metabolic genes and investigate the transcriptomic response of the organism when transitioning from a nutrient-replete to a nutrient-deficient condition when neutral lipids accumulate. Specific transcripts encoding for enzymes involved in both starch and lipid biosynthesis, among others, were up-regulated as the cultures transitioned into a lipid-accumulating state whereas photosynthesis-related genes were down-regulated. Transcripts encoding for two of the up-regulated enzymes-a galactoglycerolipid lipase and a diacylglyceride acyltransferase-were also monitored by reverse transcription quantitative polymerase chain reaction assays. The results of these assays confirmed the transcriptome-sequencing data. The present transcriptomic study will assist in the greater understanding, more effective application, and efficient design of Chlorella-based biofuel production systems.

  9. Use of De Novo Transcriptome Libraries to Characterize a Novel Oleaginous Marine Chlorella Species during the Accumulation of Triacylglycerols.

    Science.gov (United States)

    Mansfeldt, Cresten B; Richter, Lubna V; Ahner, Beth A; Cochlan, William P; Richardson, Ruth E

    2016-01-01

    Marine chlorophytes of the genus Chlorella are unicellular algae capable of accumulating a high proportion of cellular lipids that can be used for biodiesel production. In this study, we examined the broad physiological capabilities of a subtropical strain (C596) of Chlorella sp. "SAG-211-18" including its heterotrophic growth and tolerance to low salt. We found that the alga replicates more slowly at diluted salt concentrations and can grow on a wide range of carbon substrates in the dark. We then sequenced the RNA of Chlorella strain C596 to elucidate key metabolic genes and investigate the transcriptomic response of the organism when transitioning from a nutrient-replete to a nutrient-deficient condition when neutral lipids accumulate. Specific transcripts encoding for enzymes involved in both starch and lipid biosynthesis, among others, were up-regulated as the cultures transitioned into a lipid-accumulating state whereas photosynthesis-related genes were down-regulated. Transcripts encoding for two of the up-regulated enzymes-a galactoglycerolipid lipase and a diacylglyceride acyltransferase-were also monitored by reverse transcription quantitative polymerase chain reaction assays. The results of these assays confirmed the transcriptome-sequencing data. The present transcriptomic study will assist in the greater understanding, more effective application, and efficient design of Chlorella-based biofuel production systems.

  10. Ammonium nitrogen removal in batch cultures treating digested piggery wastewater with microalgae Oedogonium sp.

    Science.gov (United States)

    Wang, Haiping; Hu, Zhiquan; Xiao, Bo; Cheng, Qunpeng; Li, Fanghua

    2013-01-01

    Due to the nutrient characteristics of the high concentration of available ammonium in digested piggery wastewater (DPW), microalgae can be used to treat DPW before its final discharge. Four green microalgae (Hydrodictyaceae reticulatum Lag, Scenedesmus obliquus, Oedogonium sp. and Chlorella pyrenoidosa) and three blue-green algae (Anabaena flos-aquae, Oscillatoria amoena Gom and Spirulina platensis) were used to remove the nutrients (N, P, C), especially ammonium nitrogen (NH4(+)-N), from diluted DPW with 300 mg/L algae density in batch tests. The microalgae with the best NH4(+)-N nutrient removal was then selected for further optimization of the variables to improve NH4(+)-N removal efficiency using a central composite design (CCD) experiment. Taking into account the nutrient removal efficiency, Oedogonium sp. showed the best performance (reduction of 95.9% NH4(+)-N, 92.9% total phosphorus (TP) and 62.5% chemical oxygen demand (COD)) based on the results of the batch tests. The CCD results suggested that the optimal values of variables were initial Oedogonium sp. density of 399.2 mg/L and DPW diluted by 16.3, while the predicted value of NH4(+)-N removal efficiency obtained was 97.0%.

  11. Preventive effects of Chlorella on skeletal muscle atrophy in muscle-specific mitochondrial aldehyde dehydrogenase 2 activity-deficient mice.

    Science.gov (United States)

    Nakashima, Yuya; Ohsawa, Ikuroh; Nishimaki, Kiyomi; Kumamoto, Shoichiro; Maruyama, Isao; Suzuki, Yoshihiko; Ohta, Shigeo

    2014-10-11

    Oxidative stress is involved in age-related muscle atrophy, such as sarcopenia. Since Chlorella, a unicellular green alga, contains various antioxidant substances, we used a mouse model of enhanced oxidative stress to investigate whether Chlorella could prevent muscle atrophy. Aldehyde dehydrogenase 2 (ALDH2) is an anti-oxidative enzyme that detoxifies reactive aldehydes derived from lipid peroxides such as 4-hydroxy-2-nonenal (4-HNE). We therefore used transgenic mice expressing a dominant-negative form of ALDH2 (ALDH2*2 Tg mice) to selectively decrease ALDH2 activity in the muscles. To evaluate the effect of Chlorella, the mice were fed a Chlorella-supplemented diet (CSD) for 6 months. ALDH2*2 Tg mice exhibited small body size, muscle atrophy, decreased fat content, osteopenia, and kyphosis, accompanied by increased muscular 4-HNE levels. The CSD helped in recovery of body weight, enhanced oxidative stress, and increased levels of a muscle impairment marker, creatine phosphokinase (CPK) induced by ALDH2*2. Furthermore, histological and histochemical analyses revealed that the consumption of the CSD improved skeletal muscle atrophy and the activity of the mitochondrial cytochrome c oxidase. This study suggests that long-term consumption of Chlorella has the potential to prevent age-related muscle atrophy.

  12. Caleosin from Chlorella vulgaris TISTR 8580 is salt-induced and heme-containing protein.

    Science.gov (United States)

    Charuchinda, Pairpilin; Waditee-Sirisattha, Rungaroon; Kageyama, Hakuto; Yamada, Daisuke; Sirisattha, Sophon; Tanaka, Yoshito; Mahakhant, Aparat; Takabe, Teruhiro

    2015-01-01

    Physiological and functional properties of lipid droplet-associated proteins in algae remain scarce. We report here the caleosin gene from Chlorella vulgaris encodes a protein of 279 amino acid residues. Amino acid sequence alignment showed high similarity to the putative caleosins from fungi, but less to plant caleosins. When the C. vulgaris TISTR 8580 cells were treated with salt stress (0.3 M NaCl), the level of triacylglycerol increased significantly. The mRNA contents for caleosin in Chlorella cells significantly increased under salt stress condition. Caleosin gene was expressed in E. coli. Crude extract of E. coli cells exhibited the cumene hydroperoxide-dependent oxidation of aniline. Absorption spectroscopy showed a peak around 415 nm which was decreased upon addition of cumene hydroperoxide. Native polyacrylamide gel electrophoresis suggests caleosin existed as the oligomer. These data indicate that a fresh water C. vulgaris TISTR 8580 contains a salt-induced heme-protein caleosin.

  13. Photodegradation of 17α -Ethynylestradiol in Aqueous Solution with Nitzschia hantzschiana or Chlorella vulgaris and Fe3+

    Institute of Scientific and Technical Information of China (English)

    Liu Xian-li; Wu Feng; Liao Zhen-huan; Li Shun-xing; Deng Nan-sheng

    2004-01-01

    The photodegradation of 17α-ethynylestradiol (EE2) induced by high-pressure mercury lamp (λ≥313 nm, 250 W) in aqueous solution with algae (e.g. Nitzschia hantzschiana and Chlorella vulgaris) and Fe3+ was investigated initially. The affecting factors on the photodegradation were studied and described in details, such as algae concentration, Fe3+, exposure time, and so on. The concentration of EE2 in distilled water was determined using fluorescence spectrophotometer. The photodegradation of EE2 in aqueous solution exposed to 250 W high-pressure mercury lamp was evident in the presence of algae and Fe3+. With the algae concentration increasing, photodegradation rate increased. Fe3+ could accelerate the photocatalytic degradation of EE2 in aqueous solution with algae. The colloidal ferric hydroxide particles that might have adsorbed on the algae cells could enhance the photocatalytic degradation of EE2 by algae. The catalysis in photocatalytic degradation reaction mainly resulted from the active oxygen (H2 O2,1O2 and *OH) that was caused by algae and Fe3+ under 250 W HPML. In this paper, the mechanism of photocatalytic degradation of EE2 by algae and Fe3+ is discussed theoretically in details.

  14. Effects of pond partition on characteristics of algae and water quality in pond located at high latitudes; Anteichi wo secchishita kanreichiike no suishitsu henka to sorui tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Li, J. [Yamato Setsubi Construction Co. Ltd., Gunma (Japan); Kuroda, M. [Gunma University, Gunma (Japan). Faculty of Engineering; Wang, B. [Harbin Architectural and Civil Engineering Institute, Harbin (China). Water Pollution Control Research Center

    1995-10-10

    Characteristics of algae and water quality were studied at a pond located in high latitudes. Domestic and industrial wastewaters discharged are treated through different type stabilization ponds made by enclosing a part of the pond to remove BOD{sub 5}, COD{sub cr} and nutrients. Effects of the pond partition on the dominance species of algae and water quality were studied. During the cold term (-20{degree}C - -5{degree}C), Cryptomonas, Chlamydomonas and Euglena were dominance species in the pond. While Euglena, which may be grown by uptaking organic material was the dominance one in the stabilization pond, and its population increased in falling temperature. It plays an important role for removal of BOD{sub 5} and COD{sub cr}. On the other hand, during the warm term (15{degree}C - 30{degree}C), dominance species were Cyclotella, Chlorella and Microcystis in the pond and Scenedesmus obliqnus in facultative ponds of the stabilization ponds. Microcystis and Scenedesmus obliqnus would uptake NH4{sup +}-N truly. Removal of NH4{sup +}-N and PO4{sup 3-}-P depends on the concentration of Chl.a. The relationship between NH4{sup +}-N and PO4{sup 3-}-P removal and the concentrations of Chl.a was obtained. 11 refs., 8 figs., 3 tabs.

  15. Purification and photobiochemical profile of photosystem 1 from a high-salt tolerant, oleaginous Chlorella (Trebouxiophycaea, Chlorophyta).

    Science.gov (United States)

    McConnell, Michael D; Lowry, David; Rowan, Troy N; van Dijk, Karin; Redding, Kevin E

    2015-06-01

    The eukaryotic green alga Chlamydomonas reinhardtii has been studied extensively within the biofuel industry as a model organism, as researchers look towards algae to provide chemical feedstocks (i.e., lipids) for the production of liquid transportation fuels. C. reinhardtii, however, is unsuitable for high-level production of such precursors due to its relatively poor lipid accumulation and fresh-water demand. In this study we offer insight into the primary light harvesting and electron transfer reactions that occur during phototropic growth in a high-salt tolerant strain of Chlorella (a novel strain introduced here as NE1401), a single-celled eukaryotic algae also in the phylum Chlorophyta. Under nutrient starvation many eukaryotic algae increase dramatically the amount of lipids stored in lipid bodies within their cell interiors. Microscopy and lipid analyses indicate that Chlorella sp. NE1401 may become a superior candidate for algal biofuels production. We have purified highly active Photosystem 1 (PS1) complexes to study in vitro, so that we may understand further the photobiochemisty of this promising biofuel producer and how its characteristics compare and contrast with that of the better understood C. reinhardtii. Our findings suggest that the PS1 complex from Chlorella sp. NE1401 demonstrates similar characteristics to that of C. reinhardtii with respect to light-harvesting and electron transfer reactions. We also illustrate that the relative extent of the light state transition performed by Chlorella sp. NE1401 is smaller compared to C. reinhardtii, although they are triggered by the same dynamic light stresses.

  16. Combining urban wastewater treatment with biohydrogen production--an integrated microalgae-based approach.

    Science.gov (United States)

    Batista, Ana Paula; Ambrosano, Lucas; Graça, Sofia; Sousa, Catarina; Marques, Paula A S S; Ribeiro, Belina; Botrel, Elberis P; Castro Neto, Pedro; Gouveia, Luisa

    2015-05-01

    The aim of the present work was the simultaneous treatment of urban wastewater using microalgae and the energetic valorization of the obtained biomass. Chlorella vulgaris (Cv), Scenedesmus obliquus (Sc) and a naturally occurring algal Consortium C (ConsC) were grown in an urban wastewater. The nutrient removals were quite high and the treated water fits the legislation (PT Dec-Lei 236/98) in what concerns the parameters analysed (N, P, COD). After nutrient depletion the microalgae remained two more weeks in the photobioreactor (PBR) under nutritional stress conditions, to induce sugar accumulation (22-43%). The stressed biomass was converted into biohydrogen (bioH2), a clean energy carrier, through dark fermentation by a strain of the bacteria Enterobacter aerogenes. The fermentation kinetics were monitored and fitted to a modified Gompertz model. The highest bioH2 production yield was obtained for S. obliquus (56.8 mL H2/gVS) which was very similar when using the same algae grown in synthetic media.

  17. Molecular identification and nanoremediation of microbial contaminants in algal systems using untreated wastewater.

    Science.gov (United States)

    Limayem, Alya; Gonzalez, Francisco; Micciche, Andrew; Haller, Edward; Nayak, Bina; Mohapatra, Shyam

    2016-12-01

    Wastewater-algal biomass is a promising option to biofuel production. However, microbial contaminants constitute a substantial barrier to algal biofuel yield. A series of algal strains, Nannochloris oculata and Chlorella vulgaris samples (n = 30), were purchased from the University of Texas, and were used for both stock flask cultures and flat-panel vertical bioreactors. A number of media were used for isolation and differentiation of potential contaminants according to laboratory standards (CLSI). Conventional PCR amplification was performed followed by 16S rDNA sequencing to identify isolates at the species level. Nanotherapeutics involving a nanomicellar combination of natural chitosan and zinc oxide (CZNPs) were tested against the microbial lytic groups through Minimum Inhibitory Concentration (MIC) tests and Transmission Electronic Microscopy (TEM). Results indicated the presence of Pseudomonas spp., Bacillus pumilus/ safensis, Cellulosimicrobium cellulans, Micrococcus luteus and Staphylococcus epidermidis strains at a substantial level in the wastewater-fed algal reactors. TEM confirmed the effectiveness of CZNPs on the lytic group while the average MICs (mg/mL) detected for the strains, Pseudomonas spp, Micrococcus luteus, and Bacillus pumilus were 0.417, 3.33, and 1.458, respectively. Conclusively, CZNP antimicrobials proved to be effective as inhibitory agents against currently identified lytic microbial group, did not impact algae cells, and shows promise for in situ interventions.

  18. Nutrient removal and biofuel production in high rate algal pond using real municipal wastewater.

    Science.gov (United States)

    Kim, Byung-Hyuk; Kang, Zion; Ramanan, Rishiram; Choi, Jong-Eun; Cho, Dae-Hyun; Oh, Hee-Mock; Kim, Hee-Sik

    2014-08-01

    This study evaluated the growth and nutrient removal ability of an indigenous algal consortium on real untreated municipal wastewater in a high rate algal pond (HRAP). The HRAP was operated semicontinuously under different hydraulic retention times (HRT: 2, 4, 6, and 8 days). The average removal efficiencies of chemical oxygen demand, and total nitrogen and phosphate of real municipal wastewater were maintained at 85.44 ± 5.10%, 92.74 ± 5.82%, and 82.85 ± 8.63%, respectively, in 2 day HRT. Algae dominated the consortium and showed high settling efficiency (99%), and biomass and lipid productivity of 0.500 ± 0.03 g/l/day and 0.103 ± 0.0083 g/l/day (2 day HRT), respectively. Fatty acid methyl ester analysis revealed a predominance of palmitate (C16:0), palmitoleate (C16:1), linoleate (C18:2), and linolenate (C18:3). Microalgal diversity analyses determined the presence of Chlorella, Scenedesmus, and Stigeoclonium as the dominant microalgae. The algal consortium provides significant value not only in terms of energy savings and nutrient removal but also because of its bioenergy potential as indicated by the lipid content (20-23%) and FAME profiling.

  19. Algae production for energy and foddering

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Attila; Jobbagy, Peter; Durko, Emilia [University of Debrecen, Faculty of Applied Economics and Rural Development (UD-FAERD), Centre for Agricultural and Applied Economic Sciences, Debrecen (Hungary)

    2011-09-15

    This study not only presents the results of our own experiments in alga production, but also shows the expected economic results of the various uses of algae (animal feed, direct burning, pelleting, bio-diesel production), the technical characteristics of a new pelleting method based on literature, and also our own recommended alga production technology. In our opinion, the most promising alternative could be the production of alga species with high levels of oil content, which are suitable for utilization as by-products for animal feed and in the production of bio-diesel, as well as for use in waste water management and as a flue gas additive. Based on the data from our laboratory experiments, of the four species we analyzed, Chlorella vulgaris should be considered the most promising species for use in large-scale experiments. Taking expenses into account, our results demonstrate that the use of algae for burning technology purposes results in a significant loss under the current economic conditions; however, the utilization of algae for feeding and bio-diesel purposes - in spite of their innovative nature - is nearing the level needed for competitiveness. By using the alga production technology recommended by us and described in the present study in detail, with an investment of 545 to 727 thousand EUR/ha, this technology should be able to achieve approximately 0-29 thousand EUR/ha net income, depending on size. More favorable values emerge in the case of the 1-ha (larger) size, thanks to the significant savings on fixed costs (depreciation and personnel costs). (orig.)

  20. Physiological and ultralstructural changes of Chlorella sp. induced by UV-B radiation

    Institute of Scientific and Technical Information of China (English)

    YU Juan; TANG Xuexi; ZHANG Peiyu; TIAN Jiyuan; DONG Shuanglin

    2005-01-01

    In order to investigate the mechanisms of enhanced UV-B radiation on algae, the effects of UV-B radiation on the physiological and ultrastructural changes of Chlorella sp. were examined. The results showed that UV-B radiation could inhibit the growth and photosynthesis of microalgae. UV-B radiation at lower doses increased the photosynthetic pigment (chlorophyll a (Chla) and carotenoid (Car)) contents, while at higher doses of UV-B radiation Chla and Car contents were decreased. The ultrastructure of Chlorella sp.without exposure to UV-B showed that the thylakoidlamellae were clear and regular, the stroma of its chloroplast was apparent and clear.The globules with photosynthetic pigments and the cristae of mitochondria were clearly seen. After exposure to UV-B radiation at dose of 2.88 kJ/m2, the thylakoid lamellae of Chlorella sp. were lost and dissolved, the globules which contained photosynthetic pigments in chloroplast were bleached; some mitochondria cristae were dissolved; slight plasmolysis was found in some Chlorella sp. cells. After exposure to 5.76 kJ/m2 UV-B radiation, the thylakoid was in disarray and disintegration, plasmolysis was found in most cells, and the cell wall was broken and began to fall out. Many blank areas were observed in cells, mitochondria were seriously deformed and most of the mitochondria cristae were dissolved. Also, globules containing photosynthetic pigments in chloroplast were bleached and some empty globules were found in chloroplast. Therefore, UV-B radiation could damage cell structure of Chlorella sp., and this damage increased with the dose of UV-B radiation they exposed to.

  1. Platinum anniversary: virus and lichen alga together more than 70 years.

    Directory of Open Access Journals (Sweden)

    Karel Petrzik

    Full Text Available Trebouxia aggregata (Archibald Gärtner (phylum Chlorophyta, family Trebouxiaceae, a lichen symbiotic alga, has been identified as host of the well-known herbaceous plant virus Cauliflower mosaic virus (CaMV, family Caulimoviridae. The alga had been isolated from Xanthoria parietina more than 70 years ago and has been maintained in a collection since that time. The CaMV detected in this collection entry has now been completely sequenced. The virus from T. aggregata is mechanically transmissible to a herbaceous host and induces disease symptoms there. Its genome differs by 173 nt from the closest European CaMV-D/H isolate from cauliflower. No site under positive selection was found on the CaMV genome from T. aggregata. We therefore assume that the virus's presence in this alga was not sufficiently long to fix any specific changes in its genome. Apart from this symbiotic alga, CaMV capsid protein sequences were amplified from many other non-symbiotic algae species maintained in a collection (e.g., Oonephris obesa, Elliptochloris sp., Microthamnion kuetzingianum, Chlorella vulgaris, Pseudococcomyxa sp.. CaMV-free Chlorella vulgaris was treated with CaMV to establish virus infection. The virus was still detected there after five passages. The virus infection is morphologically symptomless on Chlorella algae and the photosynthesis activity is slightly decreased in comparison to CaMV-free alga culture. This is the first proof as to the natural presence of CaMV in algae and the first demonstration of algae being artificially infected with this virus.

  2. Phylogenetic relationships and taxonomic position of Chlorella-like isolates from low pH environments (pH < 3.0

    Directory of Open Access Journals (Sweden)

    Pinto Gabriele

    2002-08-01

    Full Text Available Abstract Background Little is known about phytoplankton communities inhabiting low pH environments such as volcanic and geothermal sites or acidic waters. Only specialised organisms are able to tolerate such extreme conditions. There is, thus, low species diversity. We have characterised the previously isolated acid tolerant Chlorella-like microalgae Viridiella fridericiana and Chlorella protothecoides var. acidicola by microscopical and biomolecular methods in order to assess their phylogenetic relationships. Results Both isolates belong to the trebouxiophycean lineage of chlorophytes. 18S and ITS1 sequence data clearly confirm that Viridiella fridericiana constitutes a new genus apart from the morphologically similar and likewise acid tolerant microalga Chlorella saccharophila. Chlorella protothecoides var. acidicola on the other hand is not a variety of Chlorella protothecoides but falls within a heterogeneous cluster consisting of Nannochloris, "Chlorella" spec. Yanaqocha, and Koliella, and is most closely related to algae which were also isolated from extreme environments. Conclusions The distribution of acid tolerant strains in the 18S rRNA tree shows that acquisition of acid tolerance was unlikely a monophyletic event in green microalgae. We propose that different strains have independently adapted to extreme environments. Some of them have spread worldwide and were able to colonise other extreme habitats. Considering the problems of successfully isolating acid tolerant strains, acidic soils could represent an unsuspected source of biological diversity with high potential for biotechnological utilisations.

  3. Critical conditions for ferric chloride-induced flocculation of freshwater algae.

    Science.gov (United States)

    Wyatt, Nicholas B; Gloe, Lindsey M; Brady, Patrick V; Hewson, John C; Grillet, Anne M; Hankins, Matthew G; Pohl, Phillip I

    2012-02-01

    The effects of algae concentration, ferric chloride dose, and pH on the flocculation efficiency of the freshwater algae Chlorella zofingiensis can be understood by considering the nature of the electrostatic charges on the algae and precipitate surfaces. Two critical conditions are identified which, when met, result in flocculation efficiencies in excess of 90% for freshwater algae. First, a minimum concentration of ferric chloride is required to overcome the electrostatic stabilization of the algae and promote bridging of algae cells by hydroxide precipitates. At low algae concentrations, the minimum amount of ferric chloride required increases linearly with algae concentration, characteristic of flocculation primarily through electrostatic bridging by hydroxide precipitates. At higher algae concentrations, the minimum required concentration of ferric chloride for flocculation is independent of algae concentration, suggesting a change in the primary flocculation mechanism from bridging to sweep flocculation. Second, the algae must have a negative surface charge. Experiments and surface complexation modeling show that the surface charge of C. zofingiensis is negative above a pH of 4.0 ± 0.3 which agrees well with the minimum pH required for effective flocculation. These critical flocculation criteria can be extended to other freshwater algae to design effective flocculation systems.

  4. Influence of phosphate on toxicity and bioaccumulation of arsenic in a soil isolate of microalga Chlorella sp.

    Science.gov (United States)

    Bahar, Md Mezbaul; Megharaj, Mallavarapu; Naidu, Ravi

    2016-02-01

    In this study, the toxicity, biotransformation and bioaccumulation of arsenite and arsenate in a soil microalga, Chlorella sp., were investigated using different phosphate levels. The results indicated that arsenate was highly toxic than arsenite to the alga, and the phosphate limitation in growth media greatly enhanced arsenate toxicity. The uptake of arsenate in algal cells was more than that of arsenite, and the predominant species in the growth media was arsenate after 8 days of exposure to arsenite or arsenate, indicating arsenite oxidation by this microalga. Arsenate reduction was also observed when the alga was incubated in a phosphate-limiting growth medium. Similar to the process of biotransformation, the alga accumulated more arsenic when it was exposed to arsenate and preferably more in a phosphate-limiting condition. Although phosphate significantly influences the biotransformation and bioaccumulation of arsenic, the oxidizing ability and higher accumulation capacity of this alga have great potential for its application in arsenic bioremediation.

  5. Effect of Feeding with Algae on Fatty Acid Profile of Goat’S Milk

    OpenAIRE

    2014-01-01

    The study was conducted to determine whether the inclusion of algae Chlorella vulgaris in dairy goats’ diets would change the fatty acid profile and increase the proportion of unsaturated fatty acids in goat’s milk. White short-haired dairy goats on 2nd and 3rd lactations were fed 5 and 10 g of dried algae supplementation for six weeks. The fatty acids profile of milk was analyzed using gass chromatography (flame ionization detector (FID)). The addition of dried algae caused changes of the pr...

  6. Photon up-conversion increases biomass yield in Chlorella vulgaris.

    Science.gov (United States)

    Menon, Kavya R; Jose, Steffi; Suraishkumar, Gadi K

    2014-12-01

    Photon up-conversion, a process whereby lower energy radiations are converted to higher energy levels via the use of appropriate phosphor systems, was employed as a novel strategy for improving microalgal growth and lipid productivity. Photon up-conversion enables the utilization of regions of the solar spectrum, beyond the typical photosynthetically active radiation, that are usually wasted or are damaging to the algae. The effects of up-conversion of red light by two distinct sets of up-conversion phosphors were studied in the model microalgae Chlorella vulgaris. Up-conversion by set 1 phosphors led to a 2.85 fold increase in biomass concentration and a 3.2 fold increase in specific growth rate of the microalgae. While up-conversion by set 2 phosphors resulted in a 30% increase in biomass and 12% increase in specific intracellular neutral lipid, while the specific growth rates were comparable to that of the control. Furthermore, up-conversion resulted in higher levels of specific intracellular reactive oxygen species in C. vulgaris. Up-conversion of red light (654 nm) was shown to improve biomass yields in C. vulgaris. In principle, up-conversion can be used to increase the utilization range of the electromagnetic spectrum for improved cultivation of photosynthetic systems such as plants, algae, and microalgae.

  7. Effects of Allelochemicals from Ficus microcarpaon Chlorella pyrenoidosa

    Directory of Open Access Journals (Sweden)

    Zhongyang Jiang

    2014-08-01

    Full Text Available This study was performed in order to isolate and identify unknown allelochemicals from Ficus microcarpa, and to investigate the inhibitory to bloom-forming of green alga Chlorella pyrenoidosa. Through gradient elution, fraction C2, whose inhibition of alga growth in diverse extracts was the strongest was shown to cause significant reductions of maximum quantum yield, as well as electron transport rates of C. pyrenoidosa. The study data also showed that the increase of fraction C2 concentration decreased the activity of total superoxide dismutase (SOD, but increased the activities of catalase (CAT and malondialdehyde (MDA content. These results demonstrate that the active fraction C2 not only induced the photoinhibition or photodamage of PSII reaction centers, but also triggered the synthesis of reactive oxygen species which may change cell membrane penetrability, thereby leading to the eventual death of C. pyrenoidosa. Furthermore, the gas chromatography/mass spectrometry (GC/MS analyses showed that the most potential allelochemical in active fraction C2 was 2-Propyl phenol, which may exhibit potent allelopathy.

  8. INMOVILIZACIÓN DE LAS MICROALGAS Scenedesmus ovalternus (Scenedesmaceae Y Chlorella vulgaris (Chlorellaceae EN ESFERAS DE ALGINATO DE CALCIO

    Directory of Open Access Journals (Sweden)

    Mario Andres Forero-Cujiño

    2016-04-01

    Full Text Available En este trabajo se describe la técnica de inmovilización de microalgas en esferas de alginato de calcio. Se emplearon las especies Scenedesmus ovalternus y Chlorella vulgaris, se determinó la estabilidad de las esferas, la cinética de crecimiento y la concentración de las microalgas en el interior de las esferas. Chlorella vulgaris alcanzó mayores densidades poblacionales y tasas de crecimiento más altas cuando se inmovilizó en concentraciones del 10 % v/v con el alginato (1,31*106 cél/ml. Para Scenedesmus ovalternus se observó una mayor densidad poblacional y una mayor tasa de crecimiento cuando se inmovilizó en concentraciones del 20 % v/v (7,06*105 cél/ml. Estos resultados son útiles para aplicaciones prácticas de las algas encapsuladas, tales como el biomonitoreo o la biorremediación.Immobilization of Microalgae Scenedesmus ovalternus (Scenedesmaceae and Chlorella vulgaris (Chlorellaceae in Calcium Alginate BeadsThis paper describes the immobilization technique of microalgae in calcium alginate beads. Scenedesmus ovalternus and Chlorella vulgaris species were used. The stability of beads, the kinetics of growth and the concentrations of microalgae inside the beads were determined. The higher density and the upper growth rate of Chlorella vulgaris occurred when it was immobilized in alginate at a concentration of 10 %v/v (1,31*106 cél/ml. Scenedesmus ovalternus achieved a higher population density and an elevated growth rate when it was immobilized at a concentration of 20 % v/v (7,06*105 cél/ml. These results are useful for subsequent applications of the encapsulated algae, such as biomonitoring and bioremediation.

  9. [Studies on chemical compounds of Chlorella sorokiniana].

    Science.gov (United States)

    Zhang, Ling; Liu, Ping-huai; Wu, Jiao-na; Yang, Guo-fu; Suo, Yang-yang; Luo, Ning; Chen, Chen

    2015-04-01

    Chemical constituents of Chlorella sorokiniana were isolated and purified by repeated column chromatographies, over silicagel and Sephadex LH-20. Their structures were identified on the basis of physicochemical properties and spectroscopic data analysis. Five compounds were obtained from the petroleum ether extract of Chlorella sorokiniana, and their structures were identified as (22E, 24R)-5alpha, 3beta-epidioxiergosta-6, 22-dien-3beta-ol(1),(24S)-ergosta-7-en-3beta-ol(2), loliolide(3), stigmasta-7,22-dien-3beta,5alpha,6alpha-triol(4), and 3beta-hydroxy-5alpha,6alpha-epoxy-7-megastigmen-9-one(5). The main liposoluble fractions from Chlorella sorokiniana maiuly contain fatty acids, alkyl acids and olefine acids. Components 1-5 were isolated from the genus Chlorella for the first time.

  10. WASTEWATER TREATMENT USING MACROALGAE KELP SP.

    Directory of Open Access Journals (Sweden)

    Suzana Elena BIRIS-DORHOI

    2016-11-01

    Full Text Available In the present study was used the alga Kelp sp. in wastewater collected from a household, in order to experiment its treatment capacities. Every measurement in this study was made using Spectoquant NOVA 60. The results show an decrease in the main parameters when low quantities of algae were used, but an increase when larger quantities were used.

  11. Optimization of Dissolved Air Flotation for Algal Harvesting at the Logan, Utah Wastewater Treatment Plant

    OpenAIRE

    Elder, Andrew R.

    2011-01-01

    This research evaluated dissolved air flotation (DAF) as a separation method for algae and phosphorus from municipal wastewater at the City of Logan, Utah Wastewater Reclamation Facility. DAF uses the supersaturation of air to raise suspended algae and other particles to the surface, where they can be easily removed. DAF, in conjunction with chemical coagulants and flocculants, can approach 95% algae and phosphorus removal. The algae removed using the DAF process will be used in the productio...

  12. Evaluación ecotóxica y genotóxica de aguas residuales hospitalarias Ecotoxicological and genotoxic evaluation of hospital wastewaters

    Directory of Open Access Journals (Sweden)

    Anahí Magdaleno

    2012-07-01

    Full Text Available Los líquidos residuales provenientes de hospitales constituyen un riesgo potencial para los ecosistemas y la salud humana debido a la presencia de compuestos tóxicos y genotóxicos. El objetivo de este trabajo fue analizar la toxicidad y la genotoxicidad de los efluentes provenientes del Hospital de Clínicas José de San Martín (Buenos Aires. Las muestras del efluente se tomaron durante los días y horarios de mayor actividad del hospital y se separaron en dos fracciones: acuosa y orgánica (extractos. Los ensayos de toxicidad se realizaron en la fracción acuosa utilizando dos especies de algas verdes: Pseudokirchneriella subcapitata y Chlorella vulgaris. La genotoxicidad se evaluó en las dos fracciones mediante el ensayo de Salmonella/ microsomas en ausencia y presencia de mezcla S9, utilizando las cepas TA98 y TA100. Veintinueve muestras de un total de 53 muestras analizadas resultaron tóxicas para P. subcapitata (entre 18 y 55 % de inhibición, mientras que sólo 8 muestras lo fueron para C. vulgaris (entre 21 y 50 % de inhibición. Ninguna de las muestras resultó genotóxica para Salmonella, ni en los extractos ni en las fracciones acuosas. De los tres ensayos utilizados, P. subcapitata fue el más sensible, siendo el ensayo más apropiado para el monitoreo de estos efluentes.Wastewaters from hospitals constitute a potential risk to the ecosystems and human health due to the presence of toxic and genotoxic chemical compounds. The objective of this work was to analyze the toxicity and genotoxicity of wastewaters from the "Hospital de Clínicas José de San Martín" (Buenos Aires. Wastewater samples were obtained during the days and hours of major hospital activities and they were separated into two fractions: aqueous and organic (extracts. The toxicity assays were performed for the aqueous fraction using the green algae species: Pseudokirchneriella subcapitata and Chlorella vulgaris. Genotoxicity was assessed for the two fraction

  13. Production and release of selenocyanate by different green freshwater algae in environmental and laboratory samples.

    Science.gov (United States)

    LeBlanc, Kelly L; Smith, Matthew S; Wallschläger, Dirk

    2012-06-05

    In a previous study, selenocyanate was tentatively identified as a biotransformation product when green algae were exposed to environmentally relevant concentrations of selenate. In this follow-up study, we confirm conclusively the presence of selenocyanate in Chlorella vulgaris culture medium by electrospray mass spectrometry, based on selenium's known isotopic pattern. We also demonstrate that the observed phenomenon extends to other green algae (Chlorella kesslerii and Scenedesmus obliquus) and at least one species of blue-green algae (Synechococcus leopoliensis). Further laboratory experiments show that selenocyanate production by algae is enhanced by addition of nitrate, which appears to serve as a source of cyanide produced in the algae. Ultimately, this biotransformation process was confirmed in field experiments where trace amounts of selenocyanate (0.215 ± 0.010 ppb) were observed in a eutrophic, selenium-impacted river with massive algal blooms, which consisted of filamentous green algae (Cladophora genus) and blue-green algae (Anabaena genus). Selenocyanate abundance was low despite elevated selenium concentrations, apparently due to suppression of selenate uptake by sulfate, and insufficient nitrogen concentrations. Finally, trace levels of several other unidentified selenium-containing compounds were observed in these river water samples; preliminary suggestions for their identities include thioselenate and small organic Se species.

  14. Epigenetic modulation of Chlorella (Chlorella vulgaris) on exposure to polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Yang, Mihi; Youn, Je-In; Kim, Seung Joon; Park, Jong Y

    2015-11-01

    DNA methylation in promoter region can be a new chemopreventive marker against polycyclic aromatic hydrocarbons (PAHs). We performed a randomized, double blind and cross-over trial (N=12 healthy females) to evaluate chlorella (Chlorella vulgaris)-induced epigenetic modulation on exposure to PAHs. The subjects consumed 4 tablets of placebo or chlorella supplement (total chlorophyll ≈ 8.3mg/tablet) three times a day before meals for 2 weeks. When the subjects consumed chlorella, status of global hypermethylation (5-methylcytosine) was reduced, compared to placebo (p=0.04). However, DNA methylation at the DNMT1 or NQO1 was not modified by chlorella. We observed the reduced levels of urinary 1-hydroxypyrene (1-OHP), a typical metabolite of PAHs, by chlorella intake (p<0.1) and a positive association between chlorella-induced changes in global hypermethylation and urinary 1-OHP (p<0.01). Therefore, our study suggests chlorella works for PAH-detoxification through the epigenetic modulation, the interference of ADME of PAHs and the interaction of mechanisms.

  15. Importance of algae as a potential source of biofuel.

    Science.gov (United States)

    Singh, A K; Singh, M P

    2014-12-24

    Algae have a great potential source of biofuels and also have unique importance to reduce gaseous emissions, greenhouse gases, climatic changes, global warming receding of glaciers, rising sea levels and loss of biodiversity. The microalgae, like Scenedesmus obliquus, Neochloris oleabundans, Nannochloropsis sp., Chlorella emersonii, and Dunaliella tertiolecta have high oil content. Among the known algae, Scenedesmus obliquus is one of the most potential sources for biodiesel as it has adequate fatty acid (linolenic acid) and other polyunsaturated fatty acids. Bio—ethanol is already in the market of United States of America and Europe as an additive in gasoline. Bio—hydrogen is the cleanest biofuel and extensive efforts are going on to bring it to market at economical price. This review highlights recent development and progress in the field of algae as a potential source of biofuel.

  16. Interactive Effects of Temperature and UV Radiation on Photosynthesis of Chlorella Strains from Polar, Temperate and Tropical Environments: Differential Impacts on Damage and Repair.

    Science.gov (United States)

    Wong, Chiew-Yen; Teoh, Ming-Li; Phang, Siew-Moi; Lim, Phaik-Eem; Beardall, John

    2015-01-01

    Global warming and ozone depletion, and the resulting increase of ultraviolet radiation (UVR), have far-reaching impacts on biota, especially affecting the algae that form the basis of the food webs in aquatic ecosystems. The aim of the present study was to investigate the interactive effects of temperature and UVR by comparing the photosynthetic responses of similar taxa of Chlorella from Antarctic (Chlorella UMACC 237), temperate (Chlorella vulgaris UMACC 248) and tropical (Chlorella vulgaris UMACC 001) environments. The cultures were exposed to three different treatments: photosynthetically active radiation (PAR; 400-700 nm), PAR plus ultraviolet-A (320-400 nm) radiation (PAR + UV-A) and PAR plus UV-A and ultraviolet-B (280-320 nm) radiation (PAR + UV-A + UV-B) for one hour in incubators set at different temperatures. The Antarctic Chlorella was exposed to 4, 14 and 20°C. The temperate Chlorella was exposed to 11, 18 and 25°C while the tropical Chlorella was exposed to 24, 28 and 30°C. A pulse-amplitude modulated (PAM) fluorometer was used to assess the photosynthetic response of microalgae. Parameters such as the photoadaptive index (Ek) and light harvesting efficiency (α) were determined from rapid light curves. The damage (k) and repair (r) rates were calculated from the decrease in ΦPSIIeff over time during exposure response curves where cells were exposed to the various combinations of PAR and UVR, and fitting the data to the Kok model. The results showed that UV-A caused much lower inhibition than UV-B in photosynthesis in all Chlorella isolates. The three isolates of Chlorella from different regions showed different trends in their photosynthesis responses under the combined effects of UVR (PAR + UV-A + UV-B) and temperature. In accordance with the noted strain-specific characteristics, we can conclude that the repair (r) mechanisms at higher temperatures were not sufficient to overcome damage caused by UVR in the Antarctic Chlorella strain

  17. Enzymic hydrolysis of chlorella cells

    Energy Technology Data Exchange (ETDEWEB)

    Khraptsova, G.I.; Tsaplina, I.A.; Burdenko, L.G.; Khoreva, S.L.; Loginova, L.G.

    1981-01-01

    Treatment of C. ellipsoidea, C. pyrenoidosa, and C. vulgaris with cellulolytic enzymes (from Aspergillus terreus) and pectofoetidin p10x (from A. foetidus) resulted in the degradation and lysis of the algae cells. The cells were more sensitive to cellulase than to pectinase. The combination of both enzymes produced a synergistic effect on cell lysis.

  18. Culture of a high-chlorophyll-producing and halotolerant Chlorella vulgaris.

    Science.gov (United States)

    Nakanishi, Koichi; Deuchi, Keiji

    2014-05-01

    In order to increase the value of freshwater algae as raw ingredients for health foods and feed for seawater-based farmed fish, we sought to breed high-chlorophyll halotolerant Chlorella with the objective of generating strains with both high chlorophyll concentrations (≥ 5%) and halotolerance (up to 1% NaCl). We used the Chlorella vulgaris K strain in our research institute culture collection and induced mutations with UV irradiation and acriflavine which is known to effect mutations of mitochondrial DNA that are associated with chlorophyll production. Screenings were conducted on seawater-based "For Chlorella spp." (FC) agar medium, and dark-green-colored colonies were visually selected by macroscopic inspection. We obtained a high-chlorophyll halotolerant strain (designated C. vulgaris M-207A7) that had a chlorophyll concentration of 6.7% (d.m.), a level at least three-fold higher than that of K strain. This isolate also exhibited a greater survival rate in seawater that of K strain.

  19. Effect of Selenate on Viability and Selenomethionine Accumulation of Chlorella sorokiniana Grown in Batch Culture

    Science.gov (United States)

    Vílchez, Carlos; Torronteras, Rafael; Vigara, Javier; Gómez-Jacinto, Veronica; Janzer, Nora; Gómez-Ariza, José-Luis; Márová, Ivana

    2014-01-01

    The aim of this work was to study the effect of Se(+VI) on viability, cell morphology, and selenomethionine accumulation of the green alga Chlorella sorokiniana grown in batch cultures. Culture exposed to sublethal Se concentrations of 40 mg·L−1 (212 μM) decreased growth rates for about 25% compared to control. A selenate EC50 value of 45 mg·L−1 (238.2 μM) was determined. Results showed that chlorophyll and carotenoids contents were not affected by Se exposure, while oxygen evolution decreased by half. Ultrastructural studies revealed granular stroma, fingerprint-like appearance of thylakoids which did not compromise cell activity. Unlike control cultures, SDS PAGE electrophoresis of crude extracts from selenate-exposed cell cultures revealed appearance of a protein band identified as 53 kDa Rubisco large subunit of Chlorella sorokiniana, suggesting that selenate affects expression of the corresponding chloroplast gene as this subunit is encoded in the chloroplast DNA. Results revealed that the microalga was able to accumulate up to 140 mg·kg−1 of SeMet in 120 h of cultivation. This paper shows that Chlorella sorokiniana biomass can be enriched in the high value aminoacid SeMet in batch cultures, while keeping photochemical viability and carbon dioxide fixation activity intact, if exposed to suitable sublethal concentrations of Se. PMID:24688385

  20. Effect of Selenate on Viability and Selenomethionine Accumulation of Chlorella sorokiniana Grown in Batch Culture

    Directory of Open Access Journals (Sweden)

    Živan Gojkovic

    2014-01-01

    Full Text Available The aim of this work was to study the effect of Se(+VI on viability, cell morphology, and selenomethionine accumulation of the green alga Chlorella sorokiniana grown in batch cultures. Culture exposed to sublethal Se concentrations of 40 mg·L−1 (212 μM decreased growth rates for about 25% compared to control. A selenate EC50 value of 45 mg·L−1 (238.2 μM was determined. Results showed that chlorophyll and carotenoids contents were not affected by Se exposure, while oxygen evolution decreased by half. Ultrastructural studies revealed granular stroma, fingerprint-like appearance of thylakoids which did not compromise cell activity. Unlike control cultures, SDS PAGE electrophoresis of crude extracts from selenate-exposed cell cultures revealed appearance of a protein band identified as 53 kDa Rubisco large subunit of Chlorella sorokiniana, suggesting that selenate affects expression of the corresponding chloroplast gene as this subunit is encoded in the chloroplast DNA. Results revealed that the microalga was able to accumulate up to 140 mg·kg−1 of SeMet in 120 h of cultivation. This paper shows that Chlorella sorokiniana biomass can be enriched in the high value aminoacid SeMet in batch cultures, while keeping photochemical viability and carbon dioxide fixation activity intact, if exposed to suitable sublethal concentrations of Se.

  1. Balance de la producción de Chlorella sp y Moina sp en la UEB PISPAVÓN, Villa Clara, Cuba (Balance of Chlorella sp and Moina sp production in the UEB PISPAVÓN, Villa Clara, Cuba

    Directory of Open Access Journals (Sweden)

    Romero-López, Teresita de J.

    2009-04-01

    Full Text Available ResumenEl presente estudio fue implementado con la información histórica existente en los archivos de PISPAVÓN, cuantificándose la producción de Chlorella sp y Moina sp en los años 2003, 2004 y 2005, las que fueron de 7 777, 5 174 y 1 988 m3 de algas y de 4 695, 3 075 y 1 557 kg del cladócero respectivamente. Esta disminución se debió al déficit de miel y cal, así como las excesivas lluvias que azotaron laregión. Mediante los estudios efectuados se determinó que la producciónde 1 kg de Moina requiere disponibilidades de Chlorella entre 1,5 y 2,0 m3.SummaryThe present study was implement with the existing historicalinformation in the PISPAVÓN archives, quantifying the production ofChlorella sp and Moina sp in 2003, 2004 and 2005, those that were of7 777, 5 174 and 1 988 m3 of microalgae and 4 695, 3 075 and 1 557kg of the cladocera respectively. This diminishing had to the deficit of honey and lime, as well as excessive rains that whipped the region. By means of the conducted studies was determined that the production of 1 kg of Moina requires availabilities of Chlorella between 1.5 and 2.0 m3.

  2. Effects of Pb(Ⅱ) exposure on Chlorella protothecoides and Chlorella vulgaris growth, malondialdehyde, and photosynthesis-related gene transcription.

    Science.gov (United States)

    Xiong, Bang; Zhang, Wei; Chen, Lin; Lin, Kuang-Fei; Guo, Mei-Jin; Wang, Wei-Liang; Cui, Xin-Hong; Bi, Hua-Song; Wang, Bin

    2014-11-01

    Greater exposure to Pb(Ⅱ) increases the likelihood of harmful effects in the environment. In this study, the aquatic unicellular alga Chlorella protothecoides (C. protothecoides) and Chlorella vulgaris (C. vulgaris) were chosen to assess the acute and chronic toxicity of Pb(Ⅱ) exposure. Results of the observations show dose-response relationships could be clearly observed between Pb(Ⅱ) concentration and percentage inhibition (PI). Exposure to Pb(Ⅱ) increased malondialdehyde (MDA) content by up to 4.22 times compared with the control, suggesting that there was some oxidative damage. ANOVA analysis shows that Pb(Ⅱ) decreased chlorophyll (chl) content, indicating marked concentration-dependent relationships, and the lowest levels of chl a, chl b, and total-chl were 14.53, 18.80, and 17.95% of the controls, respectively. A real-time PCR assay suggests the changes in transcript abundances of three photosynthetic-related genes. After 120 h exposure Pb(Ⅱ) reduced the transcript abundance of rbcL, psaB, and psbC, and the relative abundances of the three genes of C. protothecoides and C. vulgaris in response to Pb(Ⅱ) were 54.66-98.59, 51.68-95.59, 37.89-95.48, 36.04-94.94, 41.19-91.20, and 58.75-96.80% of those of the controls, respectively. As for 28 d treatments, the three genes displayed similar inhibitory trend. This research provides a basic understanding of Pb(Ⅱ) toxicity to aquatic organisms.

  3. Influence of plaque-forming bacterium, Rhodobacteraceae sp. on the growth of Chlorella vulgaris.

    Science.gov (United States)

    Chen, Zhangran; Zhang, Jingyan; Lei, Xueqian; Zhang, Bangzhou; Cai, Guanjing; Zhang, Huajun; Li, Yi; Zheng, Wei; Tian, Yun; Xu, Hong; Zheng, Tianling

    2014-10-01

    Experiments were conducted to find out the molecular features, infection process of a special alga plaque-forming microorganism and its potential influence on the biomass of Chlorella vulgaris during the infection process. Direct contact between the algal cell and the bacterium may be the primary steps needed for the bacterium to lyse the alga. Addition of C. vulgaris cells into f/2 medium allowed us obtain the object bacterium. The 16S rRNA gene sequence comparisons results showed that the plaque-forming bacterium kept the closest relationship with Labrenzia aggregata IAM 12614(T) at 98.90%. The existence of the bacterium could influence both the dry weight and lipid content of C. vulgaris. This study demonstrated that direct cell wall disruption of C. vulgaris by the bacterium would be a potentially effective method to utilize the biomass of microalgae.

  4. Photosynthetic light reactions increase total lipid accumulation in carbon-supplemented batch cultures of Chlorella vulgaris.

    Science.gov (United States)

    Woodworth, Benjamin D; Mead, Rebecca L; Nichols, Courtney N; Kolling, Derrick R J

    2015-03-01

    Microalgae are an attractive biofuel feedstock because of their high lipid to biomass ratios, lipid compositions that are suitable for biodiesel production, and the ability to grow on varied carbon sources. While algae can grow autotrophically, supplying an exogenous carbon source can increase growth rates and allow heterotrophic growth in the absence of light. Time course analyses of dextrose-supplemented Chlorella vulgaris batch cultures demonstrate that light availability directly influences growth rate, chlorophyll production, and total lipid accumulation. Parallel photomixotrophic and heterotrophic cultures grown to stationary phase reached the same amount of biomass, but total lipid content was higher for algae grown in the presence of light (an average of 1.90 mg/mL vs. 0.77 mg/mL over 5 days of stationary phase growth).

  5. Effect of isomers of hydroxybenzoic acid on the growth and metabolism of Chlorella vulgaris Beijerinck (Chlorophyceae

    Directory of Open Access Journals (Sweden)

    Andrzej Bajguz

    2014-01-01

    Full Text Available The isomers o-, m-, and p- of hydroxybenzoic acid (HBA in the concentration range 10-1-10-4 M in the unicellular green alga Chlorella vulgaris (Chlorophyceae display marked biological activity. The o-HBA isomer, commonly known as salicylic acid, in a concentration of 10-4 M exerted the most stimulating effect on the parameters analysed (the number of cells, dry mass, the content of chlorophylls a and h, carotenoids, soluble proteins and their secretion, monosaccharides, DNA and RNA whereas p-HBA had weak stimulating properties. On the other hand, m-HBA had a weak inhibitory effect on the growth of C. vulgaris and all the biochemical parameters analysed in comparison with the control culture of algae devoid of HBA isomers.

  6. PEMANFAATAN MIKROALGA LAUT Chlorella vulgaris SUMBER DHA DAN EPA

    OpenAIRE

    2016-01-01

    Penelitian tentang mikroalga laut jenis Chlorella vulgaris telah dilakukan. Chlorella vulgaris dipilih sebagai bahan penambah gizi untuk di fortifikasi kedalam makanan . Penelitian ini bertujuan untuk mengetahui kandungan gizi dengan menganalisis kandungan DHA dan EPA. Penelitian ini dilakukan dengan mengkultur fitoplankton Chlorella vulgaris dan dipanen setelah media kultur mencapai fase Stasioner. Kemudian, dikeringkan dengan menggunakan freeze dryer, biomassa kering dianalisis kandungan DH...

  7. Comparison of mixotrophic to cyclic autotrophic/heterotrophic growth strategies to optimize productivity of Chlorella sorokiniana

    DEFF Research Database (Denmark)

    van Wagenen, Jonathan Myerson; De Francisci, Davide; Angelidaki, Irini

    2015-01-01

    In addition to providing cheap or free mineral nutrients, wastewaters may contain organic carbon compounds that could increase productivity of algal cultures. This study defined a strategy for the addition of organic carbon to photobioreactors in order to improve their productivity compared...... to autotrophic growth. Chlorella sorokiniana was cultivated in medium supplemented with sodium acetate in concentrations equivalent to the volatile fatty acid concentration found in anaerobic digester effluent. Flat-panel photobioreactors were operated using 16:8 light:dark cycles, with different strategies...... in an increased efficiency of the photobioreactor....

  8. Physicochemical effects on sulfite transformation in a lipid-rich Chlorella sp. strain

    Science.gov (United States)

    Liang, Fang; Wen, Xiaobin; Luo, Liming; Geng, Yahong; Li, Yeguang

    2014-11-01

    SO2 is very rapidly hydrated to sulfurous acid in water solution at pH value above 6.0, whereby sulfite is yielded from the disassociation of protons. We aimed to improve the sulfite transformation efficiency and provide a basis for the direct utilization of SO2 from flue gas by a microalgal suspension. Chlorella sp. XQ-20044 was cultured in a medium with 20 mmol/L sodium sulfite under different physicochemical conditions. Under light conditions, sulfite concentration in the algal suspension reduced linearly over time, and was completely converted into sulfate within 8 h. The highest sulfite transformation rate (3.25 mmol/(L·h)) was obtained under the following conditions: 35°C, light intensity of 300 μmol/(m2·s), NaHCO3 concentration of 6 g/L, initial cell density (OD540) of 0.8 and pH of 9-10. There was a positive correlation between sulfite transformation rate and the growth of Chlorella, with the conditions favorable to algal growth giving better sulfite transformation. Although oxygen in the air plays a role in the transformation of SO2- 3 to SO2- 4, the transformation is mainly dependent on the metabolic activity of algal cells. Chlorella sp. XQ-20044 is capable of tolerating high sulfite concentration, and can utilize sulfite as the sole sulfur source for maintaining healthy growth. We found that sulfite ≤20 mmol/L had no obvious effect on the total lipid content and fatty acid profiles of the algae. Thus, the results suggest it is feasible to use flue gas for the mass production of feedstock for biodiesel using Chlorella sp. XQ-20044, without preliminary removal of SO2, assuming there is adequate control of the pH.

  9. Improved Productivity of Neutral Lipids in Chlorella sp. A2 by Minimal Nitrogen Supply

    Directory of Open Access Journals (Sweden)

    Junying eZhu

    2016-04-01

    Full Text Available Nitrogen starvation is an efficient environmental pressure for increasing lipid accumulation in microalgae, but it could also significantly lower the biomass productivity, resulting in lower lipid productivity. In this study, green alga Chlorella sp. A2 was cultivated by using a minimal nitrogen supply strategy under both laboratory and outdoor cultivation conditions to evaluate biomass accumulation and lipid production. Results showed that minimal nitrogen supply could promote neutral lipid accumulation of Chlorella sp. A2 without a significant negative effect on cell growth. In laboratory cultivation mode, alga cells cultured with 18 mg L-1 d-1 urea addition could generate 74% and 416% (w/w more neutral lipid productivity than cells cultured with regular BG11 and nitrogen starvation media, respectively. In outdoor cultivation mode, lipid productivity of cells cultured with 18 mg L-1 d-1 urea addition is approximately 10% and 88% higher than the one with regular BG11 and nitrogen starvation media, respectively. Notably, the results of photosynthetic analysis clarified that minimal nitrogen supply reduced the loss of photosynthetic capacity to keep CO2 fixation during photosynthesis for biomass production. The minimal nitrogen supply strategy for microalgae cultivation could promote neutral lipid accumulation without a significant negative effect on cell growth, resulting in a significant improvement in the lipid productivity.

  10. Phytoremediation of agriculture runoff by filamentous algae poly-culture for biomethane production, and nutrient recovery for secondary cultivation of lipid generating microalgae.

    Science.gov (United States)

    Bohutskyi, Pavlo; Chow, Steven; Ketter, Ben; Fung Shek, Coral; Yacar, Dean; Tang, Yuting; Zivojnovich, Mark; Betenbaugh, Michael J; Bouwer, Edward J

    2016-12-01

    An integrated system was implemented for water phytoremediation and biofuel production through sequential cultivation of filamentous algae followed by cultivation of lipid-producing microalgae Chlorella sorokiniana. Natural poly-culture of filamentous algae was grown in agricultural stormwater using the Algal Turf Scrubber®, harvested and subjected for lipid extraction and/or methane production using anaerobic digestion (AD). While filamentous algae lipid content was too low for feasible biodiesel production (algae poly-culture was exploited for waste nutrient capturing and biofuel feedstock generation. These nutrients were recovered and reused as a concentrated supplement for potentially high-value microalgae. Published by Elsevier Ltd.

  11. Bioremoval of the azo dye Congo Red by the microalga Chlorella vulgaris.

    Science.gov (United States)

    Hernández-Zamora, Miriam; Cristiani-Urbina, Eliseo; Martínez-Jerónimo, Fernando; Perales-Vela, Hugo Virgilio; Ponce-Noyola, Teresa; Montes-Horcasitas, María del Carmen; Cañizares-Villanueva, Rosa Olivia

    2015-07-01

    Discharge of dye-containing wastewater by the textile industry can adversely affect aquatic ecosystems and human health. Bioremoval is an alternative to industrial processes for detoxifying water contaminated with dyes. In this work, active and inactive biomass of the microalga Chlorella vulgaris was assayed for the ability to remove Congo Red (CR) dye from aqueous solutions. Through biosorption and biodegradation processes, Chlorella vulgaris was able to remove 83 and 58 % of dye at concentrations of 5 and 25 mg L(-1), respectively. The maximum adsorption capacity at equilibrium was 200 mg g(-1). The Langmuir model best described the experimental equilibrium data. The acute toxicity test (48 h) with two species of cladocerans indicated that the toxicity of the dye in the effluent was significantly decreased compared to the initial concentrations in the influent. Daphnia magna was the species less sensitive to dye (EC50 = 17.0 mg L(-1)), followed by Ceriodaphnia dubia (EC50 = 3.32 mg L(-1)). These results show that Chlorella vulgaris significantly reduced the dye concentration and toxicity. Therefore, this method may be a viable option for the treatment of this type of effluent.

  12. Effects of elevated CO2 on sensitivity of six species of algae and interspecific competition of three species of algae

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Effects of elevated CO2 (5000 μl/L) on sensitivity comparison of six species of algae and interspecific competition of three species of algae were investigated. The results showed that, the cell densities of six species of algae grown in elevated CO2significantly increased compared to those in ambient CO2 (360 μl/L), and with the time prolonged, the increasing extent increased.Therefore, elevated CO2 can promote the growth of six species of algae. However, there were differences in sensitivity between six species of algae. Based on the effects of elevated CO2 on biomass, the sensitive order (from high to low) was Platymanas sp.,Platymanas subcordiformis, Nitzschia closterium, Isochrysis galbana Parke 8701, Dunaliella salina, Chlorella sp., on the condition of solitary cultivation. Compared to ambient CO2, elevated CO2 promoted the growth of three species of algae, Platymanas subcordiformis, Nitzschia closterium and Isochrysis galbana Parke 8701 under the condition of mixed cultivation. The sensitivity of the three species to elevated CO2 in mixed cultivation changed a lot compared to the condition of solitary cultivation. When grown in elevated CO2 under the condition of mixed cultivation, the sensitive order from high to low were Nitzschia clostertium, Platymonas subcordiformis and Isochrysis galbana Parke 8701. However, under the condition of solitary cultivation, the sensitive order in elevated CO2 was Isochrysis galbana Parke 8701, Nitzschia clostertium, Platymonas subcordiformis, from sensitive to less sensitive. On the day 21, the dominant algae, the sub-dominant algae and inferior algae grown in elevated CO2 did not change. However, the population increasing dynamic and composition proportion of three algal species have significantly changed.

  13. MICROALGAE BIOMASS PRODUCTION BASED ON WASTEWATER FROM DAIRY INDUSTRY

    Directory of Open Access Journals (Sweden)

    Marcin Dębowski

    2016-05-01

    Full Text Available The goal of this study was to determine the feasibility of culturing high-oil algae biomass based on wastewater from dairy processing plants. The experiments were conducted in laboratory scale with tubular photobioreactor using. The best technological properties were demonstrated for eluates from an anaerobic reactor treating dairy wastewater. The use of a substrate of this type yielded algae biomass concentration at a level of 3490 mg d.m./dm3, with the mean rate of algae biomass growth at 176 mg d.m./dm3∙d. The mean content of oil in the proliferated biomass of algae approximated 20%.

  14. Antimicrobial activity of ethanolic extracts from algae against Penicillium expansum Link (Trichocomaceae, Ascomycota

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    Argus Cezar da Rocha Neto

    2015-12-01

    Full Text Available Penicillium expansum is a cosmopolitan, highly aggressive pathogen that causes blue mold, a disease of great importance that leads to losses in quality and quantity of harvested fruits. The application of chemicals is traditionally used as a control method. However, algae bioprospecting has revealed many antifungal compounds that can be used to control pathogens. Thus, the objective of this study was to evaluate the effects of ethanolic extracts from seven microalgae and five macroalgae against P. expansum. The antifungal potential was evaluated by analyzing germination percentage, the size of the germ tube, minimum inhibitory concentration (MIC, and the median effective concentration (EC50. The spectrophotometric profile was determined for extracts that showed an inhibitory effect. Among the investigated algae, the Chlorella sp. and H. pluvialis extracts, which had final concentrations of 18.8 and 125.95mg.mL-1, inhibited 100% and 91% germination, respectively. The EC50 was 2.93 and 61.20 mg.mL-1 for Chlorella sp. and H. pluvialis, respectively. Chlorella sp. showed absorption peaks in the range of chlorophyll-a and H. pluvialis presented a peak in the range of phenolic compounds. Although further studies are required to characterize the extracts, Chlorella sp. and H. pluvialis showed promising antifungal effects on the control of P. expansum.

  15. Efficacy of Chlorella pyrenoidosa and Scenedesmus abundans for Nutrient Removal in Rice Mill Effluent (Paddy Soaked Water).

    Science.gov (United States)

    Abinandan, S; Bhattacharya, Ribhu; Shanthakumar, S

    2015-01-01

    Microalgae are product of sustainable development owing to its ability to treat variety of wastewater effluents and thus produced biomass can serve as value added product for various commercial applications. This paper deals with the cultivation of microalgae species namely Chlorella pyrenoidosa and Scenedesmus abundans in rice mill effluent (i.e., paddy soaked water) for nutrient removal. In order to investigate the nutrient removal capability, microalgae are subjected to cultivation in both raw and autoclaved samples. The maximum phosphate removal by Scenedesmus abundans and Chlorella pyrenoidosa in raw sample was 98.3% and 97.6%, respectively, whereas, the removal of ammoniacal nitrogen by Scenedesmus abundans and Chlorella pyrenoidosa in raw sample was 92% and 90.3%, respectively. The growth (measured in terms of chlorophyll content) of Scenedesmus abundans and Chlorella pyrenoidosa in raw sample was 3.88 mg/l and 5.55 mg/l, respectively. The results indicate the suitability of microalgae cultivation in rice mill effluent treatment for nutrient removal.

  16. Simultaneous Production of Triacylglycerol and High-Value Carotenoids by the Astaxanthin-Producing Oleaginous Green Microalga Chlorella zofingiensis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jin; Mao, Xuemei; Zhou, Wenguang; Guarnieri, Michael T.

    2016-08-01

    The production of lipids and astaxanthin, a high-value carotenoid, by Chlorella zofingiensis was investigated under different culture conditions. Comparative analysis revealed a good correlation between triacylglycerol (TAG) and astaxanthin accumulation in C. zofingiensis. Stress conditions promoted cell size and weight and induced the accumulation of neutral lipids, especially TAG and astaxanthin, with a concomitant decrease in membrane lipids. The highest contents of TAG and astaxanthin achieved were 387 and 4.89 mg g-1 dry weight, respectively. A semi-continuous culture strategy was developed to optimize the TAG and astaxanthin productivities, which reached 297 and 3.3 mg L-1 day-1, respectively. Additionally, astaxanthin accumulation was enhanced by inhibiting de novo fatty acid biosynthesis. In summary, our study represents a pioneering work of utilizing Chlorella for the integrated production of lipids and high-value products and C. zofingiensis has great potential to be a promising production strain and serve as an emerging oleaginous model alga.

  17. Simultaneous production of triacylglycerol and high-value carotenoids by the astaxanthin-producing oleaginous green microalga Chlorella zofingiensis.

    Science.gov (United States)

    Liu, Jin; Mao, Xuemei; Zhou, Wenguang; Guarnieri, Michael T

    2016-08-01

    The production of lipids and astaxanthin, a high-value carotenoid, by Chlorella zofingiensis was investigated under different culture conditions. Comparative analysis revealed a good correlation between triacylglycerol (TAG) and astaxanthin accumulation in C. zofingiensis. Stress conditions promoted cell size and weight and induced the accumulation of neutral lipids, especially TAG and astaxanthin, with a concomitant decrease in membrane lipids. The highest contents of TAG and astaxanthin achieved were 387 and 4.89mgg(-1) dry weight, respectively. A semi-continuous culture strategy was developed to optimize the TAG and astaxanthin productivities, which reached 297 and 3.3mgL(-1)day(-1), respectively. Additionally, astaxanthin accumulation was enhanced by inhibiting de novo fatty acid biosynthesis. In summary, our study represents a pioneering work of utilizing Chlorella for the integrated production of lipids and high-value products and C. zofingiensis has great potential to be a promising production strain and serve as an emerging oleaginous model alga.

  18. Development of novel conductometric biosensors based on immobilised whole cell Chlorella vulgaris microalgae.

    Science.gov (United States)

    Chouteau, Celine; Dzyadevych, Sergei; Chovelon, Jean-Marc; Durrieu, Claude

    2004-04-15

    A novel biosensor based on immobilised whole cell Chlorella vulgaris microalgae as a bioreceptor and interdigitated conductometric electrodes as a transducer has been developed and tested for alkaline phosphatase activity (APA) analysis. These sensors were also used for the detection of toxic compounds, namely cadmium ions, in aquatic habitats. Algae were immobilised inside bovine serum albumin (BSA) membranes cross-linked with glutaraldehyde vapours. The detection of the local conductivity variations caused by algae enzymatic reactions could be achieved. The inhibition of C. vulgaris microalgae Alkaline phosphatase activities in presence of cadmium ions was measured. These results were compared with measurements in bioassays. It finally appeared that conductometric biosensors using algae seemed more sensitive than bioassays to detect low levels of cadmium ions (the detection limit for the first experiments was 1 ppb of Cd2+). The main advantages of these alkaline phosphatase biosensors consist of their high specificity in regard to the toxic compounds they enable to detect, but also on their high stability since contrary to enzymatic biosensors, they use whole algae cells with APs on their walls.

  19. Energy Productivity of the High Velocity Algae Raceway Integrated Design (ARID-HV)

    Energy Technology Data Exchange (ETDEWEB)

    Attalah, Said; Waller, Peter M.; Khawam, George; Ryan, Randy D.; Huesemann, Michael H.

    2015-06-03

    The original Algae Raceway Integrated Design (ARID) raceway was an effective method to increase algae culture temperature in open raceways. However, the energy input was high and flow mixing was poor. Thus, the High Velocity Algae Raceway Integrated Design (ARID-HV) raceway was developed to reduce energy input requirements and improve flow mixing in a serpentine flow path. A prototype ARID-HV system was installed in Tucson, Arizona. Based on algae growth simulation and hydraulic analysis, an optimal ARID-HV raceway was designed, and the electrical energy input requirement (kWh ha-1 d-1) was calculated. An algae growth model was used to compare the productivity of ARIDHV and conventional raceways. The model uses a pond surface energy balance to calculate water temperature as a function of environmental parameters. Algae growth and biomass loss are calculated based on rate constants during day and night, respectively. A 10 year simulation of DOE strain 1412 (Chlorella sorokiniana) showed that the ARID-HV raceway had significantly higher production than a conventional raceway for all months of the year in Tucson, Arizona. It should be noted that this difference is species and climate specific and is not observed in other climates and with other algae species. The algae growth model results and electrical energy input evaluation were used to compare the energy productivity (algae production rate/energy input) of the ARID-HV and conventional raceways for Chlorella sorokiniana in Tucson, Arizona. The energy productivity of the ARID-HV raceway was significantly greater than the energy productivity of a conventional raceway for all months of the year.

  20. Viruses of eukaryotic green algae. Final technical report, June 1, 1989--February 1, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Van Etten, J.L.

    1992-12-31

    We have isolated and partially characterized many large, polyhedral, DNA containing, plaque forming viruses which infect certain unicellular, eukaryotic, chlorella-like green algae. These viruses have several unique features, including the fact that they code for DNA site-specific endonucleases and DNA methyltransferases. The primary objectives of this study were to identify, clone, and characterize some of the virus-encoded DNA methyltransferases and DNA restriction endonucleases in order to understand their biological function.

  1. Simulated sugar factory wastewater remediation kinetics using algal-bacterial raceway reactor promoted by polyacrylate polyalcohol.

    Science.gov (United States)

    Memon, Abdul Rehman; Andresen, John; Habib, Muddasar; Jaffar, Muhammad

    2014-04-01

    The remediation kinetics of simulated sugar factory wastewater (SFW) using an algal-bacterial culture (ABC) of Chlorella vulgaris in association with Pseudomonas putida in a raceway reactor was found to be enhanced by 89% with the addition of 80ppm of copolymer Polyacrylate polyalcohol (PAPA). This was achieved by efficient suspension of the ABC throughout the water body maintaining optimum pH and dissolved oxygen that led to rapid COD removal and improved algal biomass production. The suspension of the ABC using the co-polymer PAPA maintained a DO of 8-10mgl(-1) compared to 2-3mgl(-1) when not suspended. As a result, the non-suspended ABC only achieved a 50% reduction in COD after 96h compared to a 89% COD removal using 80ppm PAPA suspension. In addition, the algae biomass increased from 0.4gl(-1)d(-1) for the non-suspended ABC to 1.1gl(-1)d(-1) when suspended using 80ppm PAPA.

  2. Effect of different densities of live and dead Chlorella vulgaris on the population growth of rotifers Brachionus calyciflorus and Brachionus patulus (Rotifera

    Directory of Open Access Journals (Sweden)

    E. Lucía-Pavón

    2001-12-01

    Full Text Available In order to maintain rotifer populations during periods of low algal production, it is necessary to offer alternate diets, some of which include forms of preserved algae. The present work is based on the effect of live and dead Chlorella vulgaris on the population growth of Brachionus calyciflorus and Brachionus patulus. The experimental design consisted of 3 algal levels (0.5x10(6, 1.5x10(6 and 4.5x10(6 cells ml-1 offered in 3 forms (living, frozen and heat-killed. The maximal population density values for B. calyciflorus ranged from 55±1 ind. ml-1 (at 0.5x10(6 cells ml-1 to 471±72 ind. ml-1 (at 4.5x10(6 cells ml-1 with live Chlorella, but was much lower (6±1 to 26±6 ind. ml-1 with frozen or heat-killed alga under comparable food levels. However, the maximum population density of B. patulus under live or or heat-killed Chlorella was similar at comparable algal levels but when offered frozen algae it was four times less. The highest mean peak population density was 1227±83 ind. ml-1 under 4.5x10(6 cells ml-1. The rate of population increase for B. calyciflorus varied from 0.50 to 0.79 using live Chlorella, but under comparable conditions, this range was lower (0.21 to 0.31 for B. patulus. Results have been discussed in light of possible application for aquaculturePara mantener poblaciones de rotíferos durante periodos con escasez de microalgas, es necesario ofrecer dietas alternativas, incluyendo algunas formas de microalgas preservadas. El presente trabajo analiza el efecto de Chlorella vulgaris viva y muerta sobre el crecimiento poblacional de Brachionus calyciflorus y Brachonus patulus. El diseño experimental consistió en tres niveles de algas (0.5x10(6, 1.5x10(6 y 4.5x10(6 células ml-1 ofrecidas en tres formas (viva, congelada y muerta con agua caliente. Las abundancias máximas de población de B. calyciflorus variaron desde 55±1 ind. ml-1 (en 0.5x10(6 células ml-1 a 471±72 ind. ml-1 (en 4.5x10(6 células ml-1 con Chlorella viva

  3. Photosynthetic and cellular toxicity of cadmium in Chlorella vulgaris.

    Science.gov (United States)

    Ou-Yang, Hui-Ling; Kong, Xiang-Zhen; Lavoie, Michel; He, Wei; Qin, Ning; He, Qi-Shuang; Yang, Bin; Wang, Rong; Xu, Fu-Liu

    2013-12-01

    The toxic effects of cadmium (Cd) on the green alga Chlorella vulgaris were investigated by following the response to Cd of various toxicity endpoints (cell growth, cell size, photochemical efficiency of PSII in the light or Φ(PSII), maximal photochemical efficiency or Fv/Fm, chlorophyll a fluorescence, esterase activity, and cell viability). These toxicity endpoints were studied in laboratory batch cultures of C. vulgaris over a long-term 96-h exposure to different Cd concentrations using flow cytometry and pulse amplitude modulated fluorometry. The sequence of sensitivity of these toxicity endpoints was: cell yield > Φ(PSII) ≈ esterase activity > Fv/Fm > chlorophyll a fluorescence ≈ cell viability. It is shown that cell apoptosis or cell death only accounted for a minor part of the reduction in cell yield even at very high algistatic free Cd²⁺ concentrations, and other mechanisms such as blocked cell divisions are major contributors to cell yield inhibition. Furthermore, cadmium may affect both the electron donors and acceptors of the electron transport chain at high free Cd²⁺ concentration. Finally, the resistance of cells to cell death was size-dependent; medium-sized cells had the highest toxicity threshold. The present study brings new insights into the toxicity mechanisms of Cd in C. vulgaris and provides a detailed comparison of the sensitivity of various Cd toxicity endpoints.

  4. Growth of Chlorella vulgaris and associated bacteria in photobioreactors.

    Science.gov (United States)

    Lakaniemi, Aino-Maija; Intihar, Veera M; Tuovinen, Olli H; Puhakka, Jaakko A

    2012-01-01

    The aim of this study was to test three flat plate photobioreactor configurations for growth of Chlorella vulgaris under non-axenic conditions and to characterize and quantify associated bacterial communities. The photobioreactor cultivations were conducted using tap water-based media to introduce background bacterial population. Growth of algae was monitored over time with three independent methods. Additionally, the quantity and quality of eukaryotes and bacteria were analysed using culture-independent molecular tools based on denaturing gradient gel electrophoresis (PCR-DGGE) and quantitative polymerase chain reaction (QPCR). Static mixers used in the flat plate photobioreactors did not generally enhance the growth at the low light intensities used. The maximum biomass concentration and maximum specific growth rate were 1.0 g l(-1) and 2.0 day(-1) respectively. Bacterial growth as determined by QPCR was associated with the growth of C. vulgaris. Based on PCR-DGGE, bacteria in the cultures mainly originated from the tap water. Bacterial community profiles were diverse but reproducible in all flat plate cultures. Most prominent bacteria in the C. vulgaris cultures belonged to the class Alphaproteobacteria and especially to the genus Sphingomonas. Analysis of the diversity of non-photosynthetic microorganisms in algal mass cultures can provide useful information on the public health aspects and unravel community interactions.

  5. Removal and reductive dechlorination of triclosan by Chlorella pyrenoidosa.

    Science.gov (United States)

    Wang, Shujuan; Wang, Xian; Poon, Karen; Wang, Yini; Li, Shangfu; Liu, Hongxia; Lin, Shuhai; Cai, Zongwei

    2013-09-01

    Triclosan that is widely used as antimicrobial agent has been detected as contaminant in various aquatic environments. In this work, removal and biodegradation of triclosan in water by using a ubiquitous green alga, Chlorella pyrenoidosa was investigated. When C. pyrenoidosa was exposed to a series concentration of triclosan from 100 to 800ngmL(-1), more than 50% of triclosan was eliminated by algal uptake from the culture medium during the first 1h exposure and reached equilibrium after the 6h treatment. In the biodegradation experiments, a removal percentage of 77.2% was obtained after C. pyrenoidosa was cultivated with 800ngmL(-1) triclosan for 96h. A major metabolite from the reductive dechlorination of triclosan was identified by using liquid chromatography coupled with electrospray ionization-mass spectrometry. The ultrastructural morphology of algal cells grown in the presence of triclosan was observed by using transmission electron microscopy and the growth of algal cells was detected. It was found that the trilcosan treatment resulted in the disruption of the chloroplast and the release of organic material into aquatic environment, which indicated that triclosan may affect membrane metabolism.

  6. Fuel Property of Biodiesel Made from Microalgae (Chlorella Sp.

    Directory of Open Access Journals (Sweden)

    S. V. Kelaiya,

    2015-12-01

    Full Text Available Microalgae chlorella is an organism capable of photosynthesis that is less than 2mm in diameter. The biodiesel extracted from algae using chloroform/methanol extraction solvent system then undergone three different transesterification processes based on three different catalysts viz. Alkali catalyst, Acid catalyst and Enzymatic catalyst with two temperature (50°C and 60 °C and with 1:5 methanol to bio-oil ratio. After transesterification using different catalysts, the fuel properties were measured. All the properties were compared with standard value of ASTM D 6751 standards. Alkali catalyst yield highest biodiesel (92 % at 60 °C temperature. Also, the closest value of different fuel properties found at par with standard value of ASTM D 6751 standards viz. moisture content, carbon residue, calorific value, specific gravity, acid value, flash point, viscosity, density, viscosity were found to be 0.01%, 0.04%, 40.41 MJ/kg, 0.83, 0.23 mg KOH/g, 143.67 °C, 5.16 mm2/s, 0.83 g/cm3 respectively in the biodiesel which was yield by transesterification done using Alkali catalyst (0.56 % NaOH at 60 °C temperature.

  7. Power generation enhancement in novel microbial carbon capture cells with immobilized Chlorella vulgaris

    Science.gov (United States)

    Zhou, Minghua; He, Huanhuan; Jin, Tao; Wang, Hongyu

    2012-09-01

    With the increasing concerns for global climate change, a sustainable, efficient and renewable energy production from wastewater is imperative. In this study, a novel microbial carbon capture cell (MCC), is constructed for the first time by the introduction of immobilized microalgae (Chlorella vulgaris) into the cathode chamber of microbial fuel cells (MFCs) to fulfill the zero discharge of carbon dioxide. This process can achieve an 84.8% COD removal, and simultaneously the maximum power density can reach 2485.35 mW m-3 at a current density of 7.9 A m-3 and the Coulombic efficiency is 9.40%, which are 88% and 57.7% greater than that with suspended C. vulgaris, respectively. These enhancements in performance demonstrate the feasibility of an economical and effective approach for the simultaneous wastewater treatment, electricity generation and biodiesel production from microalgae.

  8. Magnetic separation of algae

    Energy Technology Data Exchange (ETDEWEB)

    Nath, Pulak; Twary, Scott N.

    2016-04-26

    Described herein are methods and systems for harvesting, collecting, separating and/or dewatering algae using iron based salts combined with a magnetic field gradient to separate algae from an aqueous solution.

  9. Effect of Feeding with Algae on Fatty Acid Profile of Goat’S Milk

    Directory of Open Access Journals (Sweden)

    Kouřimská L.

    2014-09-01

    Full Text Available The study was conducted to determine whether the inclusion of algae Chlorella vulgaris in dairy goats’ diets would change the fatty acid profile and increase the proportion of unsaturated fatty acids in goat’s milk. White short-haired dairy goats on 2nd and 3rd lactations were fed 5 and 10 g of dried algae supplementation for six weeks. The fatty acids profile of milk was analyzed using gass chromatography (flame ionization detector (FID. The addition of dried algae caused changes of the profile of fatty acids in the milk. The more algae were added to the diet, the greater the changes in the fatty acids profile of milk were found. A statistically significant effect (P = 0.0390 was found between the control group and the group supplemented with 10 g of Chlorella vulgaris per goat per day. The greatest effect of dietary treatment was seen in the relative reduction of palmitic acid content and increased oleic, linoleic, and linolenic acids content. Results suggested that the addition of algae also increased the nutritional quality of goat’s milk. There was a positive change in the ratio of SFA:MUFA:PUFA in terms of reducing the proportion of saturated fatty acids, as well as a change in the ratio of n-6 and n-3 PUFAs

  10. Demography of zooplankton (Anuraeopsis fissa, Brachionus rubens and Moina macrocopa) fed Chlorella vulgaris and Scenedesmus acutus cultured on different media.

    Science.gov (United States)

    Morales-Ventura, Jesús; Nandini, S; Sarma, S S S; Castellanos-Páez, Maria Elena

    2012-09-01

    Generally zooplankton growth is often limited by the quality of their algal diet. A cheaper common practice in aquaculture, is to culture algae with fertilizers; however, the demography of zooplankton when fed these algae has not yet been evaluated. We studied the population growth and life table demography of the rotifers Anuraeopsis fissa and Brachionus rubens, and the cladoceran Moina macrocopa. For this, the algae Scenedesmus acutus or Chlorella vulgaris were cultured on defined (Bold's basal) medium or the commercial liquid fertilizer (Bayfolan). Experiments were conducted at one algal concentration 1.0 x 10(6) cells/mL of C. vulgaris or its equivalent dry weight of 0.5 x 10(6) cells/mL of S. acutus. The population dynamics were tested at 23 +/- 1 degrees C in 100 mL transparent jars, each with 50mL of the test medium, with an initial density of 0.5indiv/mL, for a total of 48 test jars (3 zooplankton 2 algal species x 2 culture media x 4 replicates). For the life table experiments with M. macrocopa, we introduced 10 neonates (liquid fertilizer as compared to the other diets. The growth rates of M. macrocopa ranged from 0.1 to 0.38/d, and were highest with diets of C. vulgaris cultured in Bold medium and S. acutus cultured in fertilizer. Thus, regardless of the culture medium used, the growth rates of the evaluated zooplankton species were higher with Chlorella than with Scenedesmus. The peak population density was highest (2 800ind/mL) for A. fissa fed Chlorella that was cultured on liquid fertilizers, while B. rubens and M. macrocopa had peak abundances of 480 and 12ind/mL, respectively under similar conditions.

  11. Symbiotic Chlorella variabilis incubated under constant dark conditions for 24 hours loses the ability to avoid digestion by host lysosomal enzymes in digestive vacuoles of host ciliate Paramecium bursaria.

    Science.gov (United States)

    Kodama, Yuuki; Fujishima, Masahiro

    2014-12-01

    Endosymbiosis between symbiotic Chlorella and alga-free Paramecium bursaria cells can be induced by mixing them. To establish the endosymbiosis, algae must acquire temporary resistance to the host lysosomal enzymes in the digestive vacuoles (DVs). When symbiotic algae isolated from the alga-bearing paramecia are kept under a constant dark conditions for 24 h before mixing with the alga-free paramecia, almost all algae are digested in the host DVs. To examine the cause of algal acquisition to the host lysosomal enzymes, the isolated algae were kept under a constant light conditions with or without a photosynthesis inhibitor 3-(3,4-dichlorophenyl)-1,1-dimethylurea for 24 h, and were mixed with alga-free paramecia. Unexpectedly, most of the algae were not digested in the DVs irrespective of the presence of the inhibitor. Addition of 1 mM maltose, a main photosynthetic product of the symbiotic algae or of a supernatant of the isolated algae kept for 24 h under a constant light conditions, did not rescue the algal digestion in the DVs. These observations reveal that unknown factors induced by light are a prerequisite for algal resistance to the host lysosomal enzymes.

  12. Isolation and cultivation of endosymbiotic algae from green hydra and phylogenetic analysis of 18S rDNA sequences.

    Science.gov (United States)

    Kovacević, Goran; Franjević, Damjan; Jelencić, Biserka; Kalafatić, Mirjana

    2010-01-01

    Symbiotic associations are of wide significance in evolution and biodiversity. The green hydra is a typical example of endosymbiosis. In its gastrodermal myoepithelial cells it harbors the individuals of a unicellular green algae. Endosymbiotic algae from green hydra have been successfully isolated and permanently maintained in a stable clean lab culture for the first time. We reconstructed the phylogeny of isolated endosymbiotic algae using the 18S rRNA gene to clarify its current status and to validate the traditional inclusion of these endosymbiotic algae within the Chlorella genus. Molecular analyses established that different genera and species of unicellular green algae could be present as symbionts in green hydra, depending on the natural habitat of a particular strain of green hydra.

  13. Oil from algae; salvation from peak oil?

    Science.gov (United States)

    Rhodes, Christopher J

    2009-01-01

    A review is presented of the use of algae principally to produce biodiesel fuel, as a replacement for conventional fuel derived from petroleum. The imperative for such a strategy is that cheap supplies of crude oil will begin to wane within a decade and land-based crops cannot provide more than a small amount of the fuel the world currently uses, even if food production were allowed to be severely compromised. For comparison, if one tonne of biodiesel might be produced say, from rape-seed per hectare, that same area of land might ideally yield 100 tonnes of biodiesel grown from algae. Placed into perspective, the entire world annual petroleum demand which is now provided for by 31 billion barrels of crude oil might instead be met from algae grown on an area equivalent to 4% of that of the United States. As an additional benefit, in contrast to growing crops it is not necessary to use arable land, since pond-systems might be placed anywhere, even in deserts, and since algae grow well on saline water or wastewaters, no additional burden is imposed on freshwater-a significant advantage, as water shortages threaten. Algae offer the further promise that they might provide future food supplies, beyond what can be offered by land-based agriculture to a rising global population.

  14. Bioremediation of the textile waste effluent by Chlorella vulgaris

    Directory of Open Access Journals (Sweden)

    Hala Yassin El-Kassas

    2014-01-01

    Full Text Available The microalgae biomass production from textile waste effluent is a possible solution for the environmental impact generated by the effluent discharge into water sources. The potential application of Chlorella vulgaris for bioremediation of textile waste effluent (WE was investigated using 22 Central Composite Design (CCD. This work addresses the adaptation of the microalgae C. vulgaris in textile waste effluent (WE and the study of the best dilution of the WE for maximum biomass production and for the removal of colour and Chemical Oxygen Demand (COD by this microalga. The cultivation of C. vulgaris, presented maximum cellular concentrations Cmax and maximum specific growth rates μmax in the wastewater concentration of 5.0% and 17.5%, respectively. The highest colour and COD removals occurred with 17.5% of textile waste effluent. The results of C. vulgaris culture in the textile waste effluent demonstrated the possibility of using this microalga for the colour and COD removal and for biomass production. There was a significant negative relationship between textile waste effluent concentration and Cmax at 0.05 level of significance. However, sodium bicarbonate concentration did not significantly influence the responses of Cmax and the removal of colour and COD.

  15. Bioremediation of Agro-industrial Effluents Using Chlorella Microalgae

    OpenAIRE

    Viegas, Catarina; Gonçalves, Margarida; Soares, Liliana; Mendes, Benilde

    2016-01-01

    Part 15: Bio-energy; International audience; Two microalgae species (Chlorella vulgaris and Chlorella protothecoides) were tested at lab scale in order to select the optimal conditions for biomass production and the efficient remediation of effluents from poultry and pig industries. Both microalgae showed biomass productivities in the agro-industrial effluents that were comparable to the Chlorella synthetic medium used as control. C. protothecoides presented the higher productivities both for...

  16. Wastewater Outfalls

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — Outfalls which discharge wastewater from wastewater treatment facilities with individual NPDES permits. It does not include NPDES general permits.

  17. Energy from algae using microbial fuel cells

    KAUST Repository

    Velasquez-Orta, Sharon B.

    2009-08-15

    Bioelectricity production froma phytoplankton, Chlorella vulgaris, and a macrophyte, Ulva lactuca was examined in single chamber microbial fuel cells (MFCs). MFCs were fed with the two algae (as powders), obtaining differences in energy recovery, degradation efficiency, and power densities. C. vulgaris produced more energy generation per substrate mass (2.5 kWh/kg), but U. lactuca was degraded more completely over a batch cycle (73±1% COD). Maximum power densities obtained using either single cycle or multiple cycle methods were 0.98 W/m2 (277 W/m3) using C. vulgaris, and 0.76 W/m2 (215 W/m3) using U. lactuca. Polarization curves obtained using a common method of linear sweep voltammetry (LSV) overestimated maximum power densities at a scan rate of 1 mV/s. At 0.1 mV/s, however, the LSV polarization data was in better agreement with single- and multiple-cycle polarization curves. The fingerprints of microbial communities developed in reactors had only 11% similarity to inocula and clustered according to the type of bioprocess used. These results demonstrate that algae can in principle, be used as a renewable source of electricity production in MFCs. © 2009 Wiley Periodicals, Inc.

  18. Uptake and accumulation of exogenous docosahexaenoic acid by Chlorella.

    Science.gov (United States)

    Hayashi, M; Yukino, T; Maruyama, I; Kido, S; Kitaoka, S

    2001-01-01

    Tuna oil or its hydrolysate was added to a culture of Chlorella for its nutritional fortification as a feed for rotifer. Exogenous docosahexaenoic acid (DHA) in its free form was taken up by the cells of Chlorella vulgaris strain K-22 and by other strains, but tuna oil was not taken up by the cells. Accumulated DHA was found by electron microscopy in the cells in oil droplets. All strains of Chlorella used in these experiments took up exogenous DHA into the cells. It seems that the structure of the cell wall did not affect the uptake of DHA into the Chlorella cells.

  19. Combined used of natural zeolites and microalgaes for the denitrification of wastewater from fertilizer plants; Uso combinado de zeolitas naturales y microalgas en la denitrificacion de aguas residuales

    Energy Technology Data Exchange (ETDEWEB)

    Soca Olazabal, N.; Blanco Toledo, F.; Pizarro Camacho, D.

    1997-06-01

    In our work we investigated the process of denitrification of waster-water with high percentage of nitrate and ammonia using natural zeolites that can be used later in agricultures fertilizer, because of the nitrogen load received. This effluents was used for micro algae growth reducing the nitrate concentration, the micro algae was Chlorella Vulgaris. The zeolite reduced the NH``+{sub 4} concentration up to 5 mg/l. and the NH``+{sub 4} concentration in the zeolite, it si very important in the agriculture. The chlorella Vulgaris reduces 30 mg/l of nitrate in six hours in the steady state. (Author) 9 refs.

  20. 利用微藻处理生物丁醇废水的初步研究%The Primary Studies on Treatment of Butanol Wastewater by Microalgae

    Institute of Scientific and Technical Information of China (English)

    梁锏文; 李智斌; 陈柏铨; 李璟

    2015-01-01

    The removal efficiency of COD by various microalgae in a butanol wastewater was investigated. The results showed that the Chlorella sorokiniana, Chlorella zofingiensis, Scenedesmus quadricauda and Spirulina platensis can effectively remove the COD in the butanol wastewater. The highest removal efficiency for COD(86. 56%) , total nitrogen (41. 39%), PO3-4 -P (86. 56%) were achieved by the heterotrophic cultivated Chlorella sorokiniana. In addition, the microalgae Chlorella sorokiniana achieved the highest removal efficiency of the main pollutants in butanol wastewater when the concentration of wastewater was 50%.%对比了8个微藻藻株对丁醇废水中COD的去除效率,结果表明小球藻Chlorella sorokiniana, Chlorella zofingiensis,四尾栅藻和钝顶螺旋藻能有效去除丁醇废水中的COD。试验发现小球藻Chlorella sorokiniana在异养培养方式下,能有效去除丁醇废水中的COD、总氮和 PO3-4-P。其中对 COD 的去除率最高为85.78%,对总氮的去除率为41.39%,对 PO3-4-P 的去除率为86.56%。此外,当废水浓度为50%时,小球藻Chlorella sorokiniana对丁醇废水中主要污染物的去除效率最高。

  1. The Next Generation Feedstock of Biofuel: Jatropha or Chlorella as Assessed by Their Life-Cycle Inventories

    Directory of Open Access Journals (Sweden)

    Pu Peng

    2014-07-01

    Full Text Available Promising energy crops such as Jatropha curcas Linnaeus (JCL, which are planted on marginal lands, or microalgae such as Chlorella, which are cultivated in ponds located on mudflats or deserts, have been regarded with high hopes to solve the shortage of food crops and increase the amount of biodiesel (Fatty Acid Methyl Ester, FAME production. However, the annual yields of biomass and transport fuels (t/ha of both are still unclear and often exaggerated in the literature. Large portions of JCL biomass, including tree trunks and leaves, can also be used to generate electricity along with FAME, which is produced from seed lipids. Meanwhile, lipid extracted algae (LEA are composed of proteins, polysaccharides, and lipids other than glycerides which are unable to be esterified to form FAME and much more abundant in the microalgae than oil cake in the oil crops. Therefore, it has been strongly suggested that not only transesterification or esterification but also Fischer-Tropsch (FT process and bio-electricity generation should be considered as routes to produce biofuels. Otherwise, the yield of biofuel would be extremely low using either JCL or Chlorella as feedstock. The Life-Cycle Inventories (LCI of the biofuel processes with whole biomass of JCL and Chlorella were compared based on their net energy ratio (NER and CO2 emission saving (CES. It was shown that the technological improvement of irrigation, cultivation, and processing for either economic-crops or microalgae were all necessary to meet the requirements of commercial biofuel production.

  2. Micropollutant removal in an algal treatment system fed with source separated wastewater streams

    NARCIS (Netherlands)

    de Wilt, Arnoud; Butkovskyi, Andrii; Tuantet, Kanjana; Hernandez Leal, Lucia; Fernandes, T.V.; Langenhoff, Alette; Zeeman, Grietje

    2016-01-01

    Micropollutant removal in an algal treatment system fed with source separated wastewater streams was studied. Batch experiments with the microalgae Chlorella sorokiniana grown on urine, anaerobically treated black water and synthetic urine were performed to assess the removal of six spiked pharmaceu

  3. The Bioconcentration and Degradation of Nonylphenol and Nonylphenol Polyethoxylates by Chlorella vulgaris

    Directory of Open Access Journals (Sweden)

    Hong-Wen Sun

    2014-01-01

    Full Text Available Nonylphenol polyethoxylates (NPnEOs, a major class of nonionic surfactants, can easily enter into aquatic environments through various pathways due to their wide applications, which leads to the extensive existence of their relative stable metabolites, namely nonylphenol (NP and mono- to tri-ethoxylates. This study investigated the bioconcentration and degradation of NP and NPnEO oligomers (n = 1–12 by a green algae, Chlorella vulgaris. Experimental results showed that C. vulgaris can remove NP from water phase efficiently, and bioconcentration and degradation accounted for approximately half of its loss, respectively, with a 48 h BCF (bioconcentration factor of 2.42 × 103. Moreover, C. vulgaris could concentrate and degrade NPnEOs, distribution profiles of the series homologues of the NPnEOs in algae and water phase were quite different from the initial homologue profile. The 48 h BCF of the NPnEO homologues increased with the length of the EO chain. Degradation extent of total NPnEOs by C. vulgaris was 95.7%, and only 1.1% remained in water phase, and the other 3.2% remained in the algal cells. The algae removed the NPnEOs mainly through degradation. Due to rapid degradation, concentrations of the long chain NPnEO homologous in both water (n ≥ 2 and the algal phase (n ≥ 5 was quite low at the end of a 48 h experiment.

  4. Suppression subtractive hybridization reveals transcript profiling of Chlorella under heterotrophy to photoautotrophy transition.

    Directory of Open Access Journals (Sweden)

    Jianhua Fan

    Full Text Available BACKGROUND: Microalgae have been extensively investigated and exploited because of their competitive nutritive bioproducts and biofuel production ability. Chlorella are green algae that can grow well heterotrophically and photoautotrophically. Previous studies proved that shifting from heterotrophy to photoautotrophy in light-induced environments causes photooxidative damage as well as distinct physiologic features that lead to dynamic changes in Chlorella intracellular components, which have great potential in algal health food and biofuel production. However, the molecular mechanisms underlying the trophic transition remain unclear. METHODOLOGY/PRINCIPAL FINDINGS: In this study, suppression subtractive hybridization strategy was employed to screen and characterize genes that are differentially expressed in response to the light-induced shift from heterotrophy to photoautotrophy. Expressed sequence tags (ESTs were obtained from 770 and 803 randomly selected clones among the forward and reverse libraries, respectively. Sequence analysis identified 544 unique genes in the two libraries. The functional annotation of the assembled unigenes demonstrated that 164 (63.1% from the forward library and 62 (21.8% from the reverse showed significant similarities with the sequences in the NCBI non-redundant database. The time-course expression patterns of 38 selected differentially expressed genes further confirmed their responsiveness to a diverse trophic status. The majority of the genes enriched in the subtracted libraries were associated with energy metabolism, amino acid metabolism, protein synthesis, carbohydrate metabolism, and stress defense. CONCLUSIONS/SIGNIFICANCE: The data presented here offer the first insights into the molecular foundation underlying the diverse microalgal trophic niche. In addition, the results can be used as a reference for unraveling candidate genes associated with the transition of Chlorella from heterotrophy to

  5. The Effect of Aluminium on Antibacterial Properties and the Content of Some Fatty Acids in Microalgae, Chlorella vulgaris Beijernick, under Heterotrophic and Autotrophic Conditions

    Directory of Open Access Journals (Sweden)

    Hossein Abbaspour

    2017-01-01

    Full Text Available Microalgae are a group of organisms, which have a significant potential for industrial applications. These algae contain large amounts of lipids compounds that are beneficial to health, have antibacterial properties, and their extracted oil can be used for biofuel. In this study, microalgae Chlorella vulgaris Beijernick was grown in the culture medium BG-11 containing aluminium (AlCl3 under autotrophic and heterotrophic conditions. In each case, survival and growth, dry weight, internal aluminium content of the sample, antibacterial properties, the content of fatty acids accumulated in the algae and secreted into the culture medium in the logarithmic growth phase were studied. Aluminium significantly increased (P < .05 growth and dry weight in autotrophic treatment compared to the heterotrophic one. Most antibacterial properties were observed in methanol extracts of heterotrophic treatments containing 0.05% glucose. Aluminium also decreased fatty acids accumulation in the algae and increased fatty acids excretion into the culture medium in heterotrophic treatment compared to the autotrophic treatment. Survival of the sample was maintained in heterotrophic conditions and showed growth without lag phase, which is indicative of rapid acclimation of organisms in heterotrophic conditions. It seems that the mentioned characteristics make the single-celled green algae Chlorella vulgaris more efficient in different ways.

  6. Chromate tolerance and accumulation in Chlorella vulgaris L.: role of antioxidant enzymes and biochemical changes in detoxification of metals.

    Science.gov (United States)

    Rai, U N; Singh, N K; Upadhyay, A K; Verma, S

    2013-05-01

    A concentration-dependent increase in activity of antioxidant enzymes (catalase, ascorbate peroxidase, glutathione, superoxide dismutase) and carotenoid, MDA level have been observed in the green alga Chlorella vulgaris following chromium exposure at different concentrations (0.01-100 μg ml(-1)). Simultaneously, decrease in growth rate, chlorophyll and protein contents was observed. In case of ascorbate peroxidase, glutathione peroxidase and superoxide dismutase a bell shaped dose response was evident, however, lipid peroxidation followed a linear relationship along with catalase activity, which could be used as biomarker of Cr toxicity and played important role in providing tolerance and subsequently, high accumulation potential of chromium in C. vulgaris. In present investigation, the green alga C. vulgaris respond better under chromium stress in terms of tolerance, growth and metal accumulating potential at higher concentration of Cr (VI) which could be employed in decontamination of chromium for environmental cleanup.

  7. CONSTRUCTION OF 3D MODEL FOR CYCLOBUTANE PYRIMIDINE (CPD PHOTOLYASE FROM CHLORELLA PYRENOIDOSA

    Directory of Open Access Journals (Sweden)

    Vinod Rishi

    2010-08-01

    Full Text Available Chlorella pyrenoidosa is a freshwater green alga and belongs to class Chlorophyceae, order Chlorellales and family Chlorellaceae. CPD photolyase is an enzyme found in Chlrella pyrnoidosa and responsible for repairing of DNA damages caused by UV radiations. The cyclobutane pyrimidine dimmer (CPDs and 6-4 pyrimidone photoproducts (6-4 PPs are major form of DNA damages and these damages are caused by various physical and chemical agents occurs in the environment such as UV and ionizing radiations, chemical mutagens fungal and bacterial toxins, and free radicals or alkalizing agents produced by metabolism. Mostly DNA damages induced by UV radiations, about 75% cyclobutane pyrimidinedimers (CPDs and rest 6-4 photoproducts (6-4PPs.If these are not repaired then both dimmers may be block transcription and DNA replication. CPD photolyase binds to the DNA and prevent the production of CPDs and 6-4 PPs. The three dimensional structure of CPD photolyase of Chlorella pyrenoidosa is not available for the further investigation , so it is required to generate a computational model by using Modeler 9v3 program. The quality of modeled structure is verified through various online (ProSA as well as offline (Procheck, Swiss PDB viewer tools. This protein may be useful in prevention of skin cancer.

  8. CLONING AND EXPRESSING TRYPSIN MODULATING OOSTATIC FACTOR IN Chlorella desiccata TO CONTROL MOSQUITO LARVAE.

    Science.gov (United States)

    Borovsky, Dov; Sterner, Andeas; Powell, Charles A

    2016-01-01

    The insect peptide hormone trypsin modulating oostatic factor (TMOF), a decapeptide that is synthesized by the mosquito ovary and controls the translation of the gut's trypsin mRNA was cloned and expressed in the marine alga Chlorella desiccata. To express Aedes aegypti TMOF gene (tmfA) in C. desiccata cells, two plasmids (pYES2/TMOF and pYDB4-tmfA) were engineered with pKYLX71 DNA (5 Kb) carrying the cauliflower mosaic virus (CaMV) promoter 35S(2) and the kanamycin resistant gene (neo), as well as, a 8 Kb nitrate reductase gene (nit) from Chlorella vulgaris. Transforming C. desiccata with pYES2/TMOF and pYDB4-tmfA show that the engineered algal cells express TMOF (20 ± 4 μg ± SEM and 17 ± 3 μg ± SEM, respectively in 3 × 10(8) cells) and feeding the cells to mosquito larvae kill 75 and 60% of Ae. aegypti larvae in 4 days, respectively. Southern and Northern blots analyses show that tmfA integrated into the genome of C. desiccata by homologous recombination using the yeast 2 μ circle of replication and the nit in pYES2/TMOF and pYDB4-tmfA, respectively, and the transformed algal cells express tmfA transcript. Using these algal cells it will be possible in the future to control mosquito larvae in the marsh.

  9. High efficient treatment of citric acid effluent by Chlorella vulgaris and potential biomass utilization.

    Science.gov (United States)

    Li, Changling; Yang, Hailin; Xia, Xiaole; Li, Yuji; Chen, Luping; Zhang, Meng; Zhang, Ling; Wang, Wu

    2013-01-01

    The efficiency of treating citric acid effluent by green algae Chlorella was investigated. With the highest growth rate, Chlorella vulgaris C9-JN2010 that could efficiently remove nutrients in the citric acid effluent was selected for scale-up batch experiments under the optimal conditions, where its maximum biomass was 1.04 g l(-1) and removal efficiencies of nutrients (nitrogen, phosphorus, total organic carbon, chemical oxygen demand and biochemical oxygen demand) were above 90.0%. Algal lipid and protein contents were around 340.0 and 500.0 mg · g(-1) of the harvested biomass, respectively. Proportions of polyunsaturated fatty acids in the lipids and eight kinds of essential amino acids in algal protein were 74.0% and 40.0%, respectively. Three major fatty acids were hexadecanoic acid, eicosapentaenoic acid and docosadienoic acid. This specific effluent treatment process could be proposed as a dual-beneficial approach, which converts nutrients in the high strength citric acid effluent into profitable byproducts and reduces the contaminations.

  10. Meteorological effects on variation of airborne algae in Mexico

    Science.gov (United States)

    Rosas, Irma; Roy-Ocotla, Guadalupe; Mosiño, Pedro

    1989-09-01

    Sixteen species of algae were collected from 73.8 m3 of air. Eleven were obtained in Minatitlán and eleven in México City. The data show that similar diversity occurred between the two localities, in spite of the difference in altitude. This suggests that cosmopolitan airborne microorganisms might have been released from different sources. Three major algal divisions (Chlorophyta, Cyanophyta and Chrysophyta) formed the airborne algal group. Also, a large concentration of 2220 algae m-3 was found near sea-level, while lower amounts were recorded at the high altitude of México City. The genera Scenedesmus, Chlorella and Chlorococcum dominated. Striking relationships were noted between the concentration of airborne green and blue-green algae, and meteorological conditions such as rain, vapour pressure, temperature and winds for different altitudes. In Minatitlán a linear relationship was established between concentration of algae and both vapour pressure (mbar) and temperature (° C), while in México City the wind (m s-1) was associated with variations in the algal count.

  11. Effect of nitrogen source on growth and lipid accumulation in Scenedesmus abundans and Chlorella ellipsoidea.

    Science.gov (United States)

    González-Garcinuño, Álvaro; Tabernero, Antonio; Sánchez-Álvarez, José Ma; Martin del Valle, Eva M; Galán, Miguel A

    2014-12-01

    Discovering microalgae strains containing a high lipid yield and adequate fatty acid composition is becoming a crucial fact in algae-oil factories. In this study, two unknown strains, named Scenedesmus abundans and Chlorella ellipsoidea, have been tested for their response to different nitrogen sources, in order to determine its influence in the production of lipids. For S. abundans, autotrophic culture with ammonium nitrate offers the maximum lipid yield, obtaining up to 3.55 mg L(-1) d(-1). For C. ellipsoidea, heterotrophic culture with ammonium nitrate has been shown to be the best condition, reaching a lipid production of 9.27 mg L(-1) d(-1). Moreover, fatty acid composition obtained from these cultures meets international biodiesel standards with an important amount of C18:1, achieving 70% of total fatty acids and thus representing a potential use of these two strains at an industrial scale.

  12. Infecção disseminada por Chlorella sp. em um ovino

    Directory of Open Access Journals (Sweden)

    Everton Ferreira Lima

    2014-07-01

    Full Text Available Descreve-se um caso de infecção disseminada por Chlorella sp. em um ovino, na região semiárida da Paraíba, Brasil. O animal apresentou emagrecimento e aumento de volume abdominal há um mês. Na necropsia, foram observados nódulos esverdeados em fígado, pulmões, intestino e linfonodos. Histologicamente, os nódulos correspondiam a piogranulomas com miríades de algas intralesionais. Provavelmente, a infecção tenha ocorrido em consequência do consumo de água estagnada ou capim que tinha sido cortado em uma área irrigada, que são condições frequentes no período da seca na região semiárida.

  13. OPTIMIZATION OF CELL DISRUPTION IN RAPHIDOCELIS SUBCAPITATA AND CHLORELLA VULGARIS FOR BIOMARKER EVALUATION

    Directory of Open Access Journals (Sweden)

    Adeolu Aderemi

    2015-06-01

    Full Text Available Raphidocelis subcapitata and Chlorella vulgaris are bioassay microalgae with rigid cellulosic cell wall which can hinder the release of intracellular proteins often studied as toxicity biomarkers. Since cell disruption is necessary for recovering intracellular biomolecules in these organisms, this study investigated the efficiency of ultrasonication bath; ultrasonication probe; vortexer; and bead mill in disintegrating the microalgae for anti-oxidative enzyme extraction. The extent of cell disruption was evaluated and quantified using bright field microscopy. Disrupted algae appeared as ghosts. The greatest disintegration of the microalgae (83-99.6 % was achieved using bead mill with 0.42-0.6 mm glass beads while the other methods induced little or no disruption. The degree of cell disruption using bead mill increased with exposure time, beads-solution ratio and agitation speed while larger beads caused less disruption. Findings revealed that bead milling, with specific parameters optimized, is one of the most effective methods of disintegrating the robust algal cells.

  14. Change in Photosystem II Photochemistry During Algal Growth Phases of Chlorella vulgaris and Scenedesmus obliquus.

    Science.gov (United States)

    Oukarroum, Abdallah

    2016-06-01

    Sensitivity of photosynthetic processes towards environmental stress is used as a bioanalytical tool to evaluate the responses of aquatic plants to a changing environment. In this paper, change of biomass density, chlorophyll a fluorescence and photosynthetic parameters during growth phases of two microalgae Chlorella vulgaris and Scenedesmus obliquus were studied. The photosynthetic growth behaviour changed significantly with cell age and algae species. During the exponential phase of growth, the photosynthesis capacity reached its maximum and decreased in ageing algal culture during stationary phase. In conclusion, the chlorophyll a fluorescence OJIP method and the derived fluorescence parameters would be an accurate method for obtaining information on maximum photosynthetic capacities and monitoring algal cell growth. This will contribute to more understanding, for example, of toxic actions of pollutants in microalgae test.

  15. The Chlorella killed by pulsed electrical discharge in liquid with two different reactors

    Science.gov (United States)

    Gao, Z. Y.; Sun, B.; Yan, Z. Y.; Zhu, X. M.; Liu, H.; Song, Y. J.; Sato, M.

    2013-03-01

    The application of pulsed high-voltage discharge in liquid has attracted wide attention as an effective water treatment. In this paper, two different liquid high-voltage discharge systems were constructed with plate-hole-plate and needle-plate electrode structures, and the inactivation behaviors of Chlorella were studied in the two reactors. The results show that the killing rates of algae in both reactors all increased significantly with increasing discharge voltage and the killing rates were intensely related to discharge power, instantaneous power and single pulse input energy. Furthermore, the inactivation effect in needle-plate reactor was superior to that in plate-hole-plate reactor under the same experimental conditions.

  16. Identification of Sporopollenin as the Outer Layer of Cell Wall in Microalga Chlorella protothecoides

    Science.gov (United States)

    He, Xi; Dai, Junbiao; Wu, Qingyu

    2016-01-01

    Chlorella protothecoides has been put forth as a promising candidate for commercial biodiesel production. However, the cost of biodiesel remains much higher than diesel from fossil fuel sources, partially due to the high costs of oil extraction from algae. Here, we identified the presence of a sporopollenin layer outside the polysaccharide cell wall; this was evaluated using transmission electron microscopy, 2-aminoethanol treatment, acetolysis, and Fourier Transform Infrared Spectroscopy. We also performed bioinformatics analysis of the genes of the C. protothecoides genome that are likely involved in sporopollenin synthesis, secretion, and translocation, and evaluated the expression of these genes via real-time PCR. We also found that that removal of this sporopollenin layer greatly improved the efficiency of oil extraction. PMID:27446068

  17. Alkaloids in Marine Algae

    OpenAIRE

    Ekrem Sezik; Aline Percot; Kasım Cemal Güven

    2010-01-01

    This paper presents the alkaloids found in green, brown and red marine algae. Algal chemistry has interested many researchers in order to develop new drugs, as algae include compounds with functional groups which are characteristic from this particular source. Among these compounds, alkaloids present special interest because of their pharmacological activities. Alkaloid chemistry has been widely studied in terrestrial plants, but the number of studies in algae is insignificant. In this review...

  18. Genome-based metabolic mapping and 13C flux analysis reveal systematic properties of an oleaginous microalga Chlorella protothecoides.

    Science.gov (United States)

    Wu, Chao; Xiong, Wei; Dai, Junbiao; Wu, Qingyu

    2015-02-01

    Integrated and genome-based flux balance analysis, metabolomics, and (13)C-label profiling of phototrophic and heterotrophic metabolism in Chlorella protothecoides, an oleaginous green alga for biofuel. The green alga Chlorella protothecoides, capable of autotrophic and heterotrophic growth with rapid lipid synthesis, is a promising candidate for biofuel production. Based on the newly available genome knowledge of the alga, we reconstructed the compartmentalized metabolic network consisting of 272 metabolic reactions, 270 enzymes, and 461 encoding genes and simulated the growth in different cultivation conditions with flux balance analysis. Phenotype-phase plane analysis shows conditions achieving theoretical maximum of the biomass and corresponding fatty acid-producing rate for phototrophic cells (the ratio of photon uptake rate to CO2 uptake rate equals 8.4) and heterotrophic ones (the glucose uptake rate to O2 consumption rate reaches 2.4), respectively. Isotope-assisted liquid chromatography-mass spectrometry/mass spectrometry reveals higher metabolite concentrations in the glycolytic pathway and the tricarboxylic acid cycle in heterotrophic cells compared with autotrophic cells. We also observed enhanced levels of ATP, nicotinamide adenine dinucleotide (phosphate), reduced, acetyl-Coenzyme A, and malonyl-Coenzyme A in heterotrophic cells consistently, consistent with a strong activity of lipid synthesis. To profile the flux map in experimental conditions, we applied nonstationary (13)C metabolic flux analysis as a complementing strategy to flux balance analysis. The result reveals negligible photorespiratory fluxes and a metabolically low active tricarboxylic acid cycle in phototrophic C. protothecoides. In comparison, high throughput of amphibolic reactions and the tricarboxylic acid cycle with no glyoxylate shunt activities were measured for heterotrophic cells. Taken together, the metabolic network modeling assisted by experimental metabolomics and (13)C

  19. Differential effects of P25 TiO{sub 2} nanoparticles on freshwater green microalgae: Chlorella and Scenedesmus species

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Rajdeep; Parashar, Abhinav; Bhuvaneshwari, M.; Chandrasekaran, N.; Mukherjee, Amitava, E-mail: amit.mookerjea@gmail.com

    2016-07-15

    Highlights: • Differential effects of P25 TiO{sub 2} NPs on Chlorella and Scenedesmus. • Concentration dependent effects in morphology and viability. • Increased ROS, catalase activity & LPO release with loss in SOD & GSH activity. • Dose dependent differential TiO{sub 2} NPs uptake affected by colonization of algae. - Abstract: P25 TiO{sub 2} nanoparticles majorly used in cosmetic products have well known detrimental effects towards the aquatic environment. In a freshwater ecosystem, Chlorella and Scenedesmus are among the most commonly found algal species frequently used to study the effects of metal oxide nanoparticles. A comparative study has been conducted herein to investigate differences in the toxic effects caused by these nanoparticles towards the two algae species. The three different concentrations of P25 TiO{sub 2} NPs (0.01, 0.1 & 1 μg/mL, i.e., 0.12, 1.25 and 12.52 μM) were selected to correlate surface water concentrations of the nanoparticles, and filtered and sterilized fresh water medium was used throughout this study. There was significant increase (p < 0.001) in hydrodynamic diameter of nanoparticles with respect to both, time (0, 24, 48 and 72 h) as well as concentration under all the exposure conditions. Although, significant dose-dependent morphological (surface area & biovolume) interspecies variations were not observed, it was evident at the highest concentration of exposure within individuals. At 1 μg/mL exposure concentration, a significant difference in toxicity was noted between Chlorella and Scenedesmus under only visible light (p < 0.001) and UVA (p < 0.01) irradiation conditions. The viability data were well supported by the results obtained for oxidative stress induced by NPs on the cells. At the highest exposure concentration, superoxide dismutase and reduced glutathione activities were assessed for both the algae under all the irradiation conditions. Increased catalase activity and LPO release complemented the cytotoxic

  20. Impact of algal organic matter released from Microcystis aeruginosa and Chlorella sp. on the fouling of a ceramic microfiltration membrane.

    Science.gov (United States)

    Zhang, Xiaolei; Devanadera, Ma Catriona E; Roddick, Felicity A; Fan, Linhua; Dalida, Maria Lourdes P

    2016-10-15

    Algal blooms lead to the secretion of algal organic matter (AOM) from different algal species into water treatment systems, and there is very limited information regarding the impact of AOM from different species on the fouling of ceramic microfiltration (MF) membranes. The impact of soluble AOM released from Microcystis aeruginosa and Chlorella sp. separately and together in feedwater on the fouling of a tubular ceramic microfiltration membrane (alumina, 0.1 μm) was studied at lab scale. Multi-cycle MF tests operated in constant pressure mode showed that the AOM (3 mg DOC L(-1)) extracted from the cultures of the two algae in early log phase of growth (12 days) resulted in less flux decline compared with the AOM from stationary phase (35 days), due to the latter containing significantly greater amounts of high fouling potential components (protein and humic-like substances). The AOM released from Chlorella sp. at stationary phase led to considerably greater flux decline and irreversible fouling resistance compared with that from M. aeruginosa. The mixture of the AOM (1:1, 3 mg DOC L(-1)) from the two algal species showed more similar flux decline and irreversible fouling resistance to the AOM from M. aeruginosa than Chlorella sp. This was due to the characteristics of the AOM mixture being more similar to those for M. aeruginosa than Chlorella sp. The extent of the flux decline for the AOM mixture after conventional coagulation with aluminium chlorohydrate or alum was reduced by 70%.

  1. A Comprehensive Study on Chlorella pyrenoidosa for Phenol Degradation and its Potential Applicability as Biodiesel Feedstock and Animal Feed.

    Science.gov (United States)

    Das, Bhaskar; Mandal, Tapas K; Patra, Sanjukta

    2015-07-01

    The present work evaluates the phenol degradative performance of microalgae Chlorella pyrenoidosa. High-performance liquid chromatography (HPLC) analysis showed that C. pyrenoidosa degrades phenol completely up to 200 mg/l. It could also metabolize phenol in refinery wastewater. Biokinetic parameters obtained are the following: growth kinetics, μ max (media) > μ max (refinery wastewater), K s(media)  K I(refinery wastewater); degradation kinetics, q max (media) > q max (refinery wastewater), K s(media)  K I(refinery wastewater). The microalgae could cometabolize the alkane components present in refinery wastewater. Fourier transform infrared (FTIR) fingerprinting of biomass indicates intercellular phenol uptake and breakdown into its intermediates. Phenol was metabolized as an organic carbon source leading to higher specific growth rate of biomass. Phenol degradation pathway was elucidated using HPLC, liquid chromatography-mass spectrometry (LC-MS) and ultraviolet-visible (UV-visible) spectrophotometry. It involved both ortho- and meta-pathway with prominence of ortho-pathway. SEM analysis shows that cell membrane gets wrinkled on phenol exposure. Phenol degradation was growth and photodependent. Infrared analysis shows increased intracellular accumulation of neutral lipids opening possibility for utilization of spent biomass as biodiesel feedstock. The biomass after lipid extraction could be used as protein supplement in animal feed owing to enhanced protein content. The phenol remediation ability coupled with potential applicability of the spent biomass as biofuel feedstock and animal feed makes it a potential candidate for an environmentally sustainable process.

  2. Purification on N and P in Aquiculturie Wastewater with a Bacteria-Alga System%菌-藻体系去除水产养殖废水中氮和磷的净化实验

    Institute of Scientific and Technical Information of China (English)

    周武旋; 赵江萍; 栗越妍

    2012-01-01

    以投加人工饲料喂养罗非鱼7天的玻璃鱼缸内的废水为样品,接种地衣芽孢杆菌(Bacillus licheniformis)、硝化细菌、月牙藻(Selenastrum reinsch)和四尾栅藻(Scenedesmus quadricanda)后于光照箱内培养,于0、12h、24h、48h、84h、120h、168h测定废水样品的pH值、溶解氧、氨氮、亚硝酸盐氮、硝酸盐氮和可溶性磷酸盐的去除率,以24h氨氮和168h可溶性磷酸盐的去除率为指标进行L3(34)正交实验,研究菌藻体系去除水产养殖废水中氮和磷的净化效果.结果表明,地衣芽孢杆菌、硝化细菌、月牙藻和四尾栅藻组成的菌-藻体系可以通过其新陈代谢过程中形成的原始共生关系有效地去除养殖水体中的氮、磷污染物.菌-藻体系去除氨氮的最佳反应时间为24h,最大去除率98%,在初始密度为5×105 cells/ml条件下,最佳菌-藻体积配比为1∶2∶2∶3,即最佳菌-藻初始密度分别为2.5×10s cell/ml、5.0×105 cell/ml、5.0×105 cell/ml、10.0×l05 cell/ml.菌-藻体系去除可溶性磷酸盐的最佳反应时间为168h,去除率100%,在初始密度为5×105 cells/ml条件下,最佳菌藻体积配比为1∶1∶3∶2,即最佳菌-藻初始密度分别为2.5×105 cell/ml、2.5× 105 cell/ml、10.0×10s cell/ml、5.0×105 cell/ml.%Using the waste water after feeding tuapia 7 days with artificial additive in the aquarium glass as samples. Bacillus licheniformis (Bacillus licheniformis ), nitrifying bacteria , crescent algae ( Selenastrum reinsch ) and four tail gate algae ( Scenedesmus quadricanda )were vaccinated and cultured in the light box. pH value,dissolved oxygen,ammonia nitrogen,nitrite nitrogen,nitrate nitrogen and soluble phosphate removal rate of the waste water samples were measured after 0,12h,24h,48h,84h,120h and 168h, respectively cultivation. ThenL9( 34) orthogonal experiments were conducted to analyze the ammonia nitrogen at 24h and the removal rate of soluble phosphate at 168h, in order to

  3. Cell proliferation alterations in Chlorella cells under stress conditions

    Energy Technology Data Exchange (ETDEWEB)

    Rioboo, Carmen [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain); O' Connor, Jose Enrique [Laboratorio de Citomica, Unidad Mixta de Investigacion CIPF-UVEG, Centro de Investigacion Principe Felipe, Avda. Autopista del Saler, 16, 46013 Valencia (Spain); Prado, Raquel; Herrero, Concepcion [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain); Cid, Angeles, E-mail: cid@udc.es [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain)

    2009-09-14

    Very little is known about growth and proliferation in relation to the cell cycle regulation of algae. The lack of knowledge is even greater when referring to the potential toxic effects of pollutants on microalgal cell division. To assess the effect of terbutryn, a triazine herbicide, on the proliferation of the freshwater microalga Chlorella vulgaris three flow cytometric approaches were used: (1) in vivo cell division using 5-,6-carboxyfluorescein diacetate succinimidyl ester (CFSE) staining was measured, (2) the growth kinetics were determined by cytometric cell counting and (3) cell viability was evaluated with the membrane-impermeable double-stranded nucleic acid stain propidium iodide (PI). The results obtained in the growth kinetics study using CFSE to identify the microalgal cell progeny were consistent with those determined by cytometric cell counting. In all C. vulgaris cultures, each mother cell had undergone only one round of division through the 96 h of assay and the cell division occurred during the dark period. Cell division of the cultures exposed to the herbicide was asynchronous. Terbutryn altered the normal number of daughter cells (4 autospores) obtained from each mother cell. The number was only two in the cultures treated with 250 nM. The duration of the lag phase after the exposure to terbutryn could be dependent on the existence of a critical cell size to activate cytoplasmic division. Cell size, complexity and fluorescence of chlorophyll a of the microalgal cells presented a marked light/dark (day/night) cycle, except in the non-dividing 500 nM cultures, where terbutryn arrested cell division at the beginning of the cycle. Viability results showed that terbutryn has an algastatic effect in C. vulgaris cells at this concentration. The rapid and precise determination of cell proliferation by CFSE staining has allowed us to develop a model for assessing both the cell cycle of C. vulgaris and the in vivo effects of pollutants on growth and

  4. Two stage treatment of dairy effluent using immobilized Chlorella pyrenoidosa.

    Science.gov (United States)

    Yadavalli, Rajasri; Heggers, Goutham Rao Venkata Naga

    2013-12-19

    Dairy effluents contains high organic load and unscrupulous discharge of these effluents into aquatic bodies is a matter of serious concern besides deteriorating their water quality. Whilst physico-chemical treatment is the common mode of treatment, immobilized microalgae can be potentially employed to treat high organic content which offer numerous benefits along with waste water treatment. A novel low cost two stage treatment was employed for the complete treatment of dairy effluent. The first stage consists of treating the diary effluent in a photobioreactor (1 L) using immobilized Chlorella pyrenoidosa while the second stage involves a two column sand bed filtration technique. Whilst NH4+-N was completely removed, a 98% removal of PO43--P was achieved within 96 h of two stage purification processes. The filtrate was tested for toxicity and no mortality was observed in the zebra fish which was used as a model at the end of 96 h bioassay. Moreover, a significant decrease in biological oxygen demand and chemical oxygen demand was achieved by this novel method. Also the biomass separated was tested as a biofertilizer to the rice seeds and a 30% increase in terms of length of root and shoot was observed after the addition of biomass to the rice plants. We conclude that the two stage treatment of dairy effluent is highly effective in removal of BOD and COD besides nutrients like nitrates and phosphates. The treatment also helps in discharging treated waste water safely into the receiving water bodies since it is non toxic for aquatic life. Further, the algal biomass separated after first stage of treatment was highly capable of increasing the growth of rice plants because of nitrogen fixation ability of the green alga and offers a great potential as a biofertilizer.

  5. Landfill leachate--a water and nutrient resource for algae-based biofuels.

    Science.gov (United States)

    Edmundson, Scott J; Wilkie, Ann C

    2013-01-01

    There is a pressing need for sustainable renewable fuels that do not negatively impact food and water resources. Algae have great potential for the production of renewable biofuels but require significant water and fertilizer resources for large-scale production. Municipal solid waste (MSW) landfill leachate (LL) was evaluated as a cultivation medium to reduce both water and elemental fertilizer demands of algae cultivation. Daily growth rate and cell yield of two isolated species of algae (Scenedesmus cf. rubescens and Chlorella cf. ellipsoidea) were cultivated in MSW LL and compared with Bold's Basal Medium (BBM). Results suggest that LL can be used as a nutrient resource and medium for the cultivation of algae biomass. S. cf. rubescens grew well in 100% LL, when pH was regulated, with a mean growth rate and cell yield 91.2% and 92.8% of those observed in BBM, respectively. S. cf. rubescens was more adaptable than C. cf. ellipsoidea to the LL tested. The LL used in this study supported a maximum volumetric productivity of 0.55 g/L/day of S. cf. rubescens biomass. The leachate had sufficient nitrogen to supply 17.8 g/L of algae biomass, but was limited by total phosphorus. Cultivation of algae on LL offsets both water and fertilizer consumption, reducing the environmental footprint and increasing the potential sustainability of algae-based biofuels.

  6. Deep RNA sequencing reveals hidden features and dynamics of early gene transcription in Paramecium bursaria chlorella virus 1.

    Directory of Open Access Journals (Sweden)

    Guillaume Blanc

    Full Text Available Paramecium bursaria chlorella virus 1 (PBCV-1 is the prototype of the genus Chlorovirus (family Phycodnaviridae that infects the unicellular, eukaryotic green alga Chlorella variabilis NC64A. The 331-kb PBCV-1 genome contains 416 major open reading frames. A mRNA-seq approach was used to analyze PBCV-1 transcriptomes at 6 progressive times during the first hour of infection. The alignment of 17 million reads to the PBCV-1 genome allowed the construction of single-base transcriptome maps. Significant transcription was detected for a subset of 50 viral genes as soon as 7 min after infection. By 20 min post infection (p.i., transcripts were detected for most PBCV-1 genes and transcript levels continued to increase globally up to 60 min p.i., at which time 41% or the poly (A+-containing RNAs in the infected cells mapped to the PBCV-1 genome. For some viral genes, the number of transcripts in the latter time points (20 to 60 min p.i. was much higher than that of the most highly expressed host genes. RNA-seq data revealed putative polyadenylation signal sequences in PBCV-1 genes that were identical to the polyadenylation signal AAUAAA of green algae. Several transcripts have an RNA fragment excised. However, the frequency of excision and the resulting putative shortened protein products suggest that most of these excision events have no functional role but are probably the result of the activity of misled splicesomes.

  7. Organic and Inorganic Nitrogen Impact Chlorella variabilis Productivity and Host Quality for Viral Production and Cell Lysis.

    Science.gov (United States)

    Cheng, Yu-Shen; Labavitch, John; VanderGheynst, Jean S

    2015-05-01

    Microalgae have been proposed as a potential feedstock for biofuel production; however, cell disruption is usually required for collection and utilization of cytoplasmic polysaccharides and lipids. Virus infection might be one approach to disrupt the cell wall. The concentration of yeast extract and presence of KNO3 in algae cultivation media were investigated to observe their effects on Chlorella variabilis NC64A physiology and composition and the subsequent effect on production of Chlorella virus and disruption of infected cells. Cytoplasmic starch accumulation increased from 5% to approximately 35% of the total dry weight when yeast extract decreased from 1 to 0.25 g L(-1). When cells were cultured with the lowest nitrogen levels, the total polysaccharide accounted for more than 50% of the cell wall, which was 1.7 times higher than the content in cells cultured with the highest nitrogen levels. The C/N ratio of the algal biomass decreased by a factor of approximately 2 when yeast extract increased from 0.25 to 1 g L(-1). After virus infection, cells with a low C/N ratio produced a 7.6 times higher burst size than cells with a high C/N ratio, suggesting that the nitrogen content in C. variabilis has a large influence on viral production and cell lysis. The results have implications on management of nitrogen for both the synthesis of products from algae and product recovery via viral lysis.

  8. Microalgae and wastewater treatment

    Science.gov (United States)

    Abdel-Raouf, N.; Al-Homaidan, A.A.; Ibraheem, I.B.M.

    2012-01-01

    Organic and inorganic substances which were released into the environment as a result of domestic, agricultural and industrial water activities lead to organic and inorganic pollution. The normal primary and secondary treatment processes of these wastewaters have been introduced in a growing number of places, in order to eliminate the easily settled materials and to oxidize the organic material present in wastewater. The final result is a clear, apparently clean effluent which is discharged into natural water bodies. This secondary effluent is, however, loaded with inorganic nitrogen and phosphorus and causes eutrophication and more long-term problems because of refractory organics and heavy metals that are discharged. Microalgae culture offers an interesting step for wastewater treatments, because they provide a tertiary biotreatment coupled with the production of potentially valuable biomass, which can be used for several purposes. Microalgae cultures offer an elegant solution to tertiary and quandary treatments due to the ability of microalgae to use inorganic nitrogen and phosphorus for their growth. And also, for their capacity to remove heavy metals, as well as some toxic organic compounds, therefore, it does not lead to secondary pollution. In the current review we will highlight on the role of micro-algae in the treatment of wastewater. PMID:24936135

  9. Microalgae and wastewater treatment.

    Science.gov (United States)

    Abdel-Raouf, N; Al-Homaidan, A A; Ibraheem, I B M

    2012-07-01

    Organic and inorganic substances which were released into the environment as a result of domestic, agricultural and industrial water activities lead to organic and inorganic pollution. The normal primary and secondary treatment processes of these wastewaters have been introduced in a growing number of places, in order to eliminate the easily settled materials and to oxidize the organic material present in wastewater. The final result is a clear, apparently clean effluent which is discharged into natural water bodies. This secondary effluent is, however, loaded with inorganic nitrogen and phosphorus and causes eutrophication and more long-term problems because of refractory organics and heavy metals that are discharged. Microalgae culture offers an interesting step for wastewater treatments, because they provide a tertiary biotreatment coupled with the production of potentially valuable biomass, which can be used for several purposes. Microalgae cultures offer an elegant solution to tertiary and quandary treatments due to the ability of microalgae to use inorganic nitrogen and phosphorus for their growth. And also, for their capacity to remove heavy metals, as well as some toxic organic compounds, therefore, it does not lead to secondary pollution. In the current review we will highlight on the role of micro-algae in the treatment of wastewater.

  10. Demography of zooplankton (Anuraeopsis fissa, Brachionus rubens and Moina macrocopa fed Chlorella vulgaris and Scenedesmus acutus cultured on different media

    Directory of Open Access Journals (Sweden)

    Jesús Morales-Ventura

    2012-09-01

    Full Text Available Generally zooplankton growth is often limited by the quality of their algal diet. A cheaper common practice in aquaculture, is to culture algae with fertilizers; however, the demography of zooplankton when fed these algae has not yet been evaluated. We studied the population growth and life table demography of the rotifers Anuraeopsis fissa and Brachionus rubens, and the cladoceran Moina macrocopa. For this, the algae Scenedesmus acutus or Chlorella vulgaris were cultured on defined (Bold’s basal medium or the commercial liquid fertilizer (Bayfolan. Experiments were conducted at one algal concentration 1.0x10(6cells/mL of C. vulgaris or its equivalent dry weight of 0.5x10(6cells/mL of S. acutus. The population dynamics were tested at 23±1ºC in 100mL transparent jars, each with 50mL of the test medium, with an initial density of 0.5indiv/mL, for a total of 48 test jars (3 zooplankton 2 algal species x 2 culture media x 4 replicates. For the life table experiments with M. macrocopa, we introduced 10 neonates (Generalmente el crecimiento del zooplancton está a menudo limitado por la calidad de su dieta de algas. La demografía del zooplancton durante la alimentación con algas no ha sido estudiada, a pesar de que el cultivo de algas con fertilizantes es una práctica económica común en acuacultura. Se analizó la demografía de Anuraeopsis fissa y Brachionus rubens (rotíferos y Moina macrocopa (cladóceros, alimentados con las algas verdes Scenedesmus acutus o Chlorella vulgaris cultivadas en medio Bold o fertilizante líquido comercial (Bayfolan, de Bayer. En los rotíferos no se observaron diferencias significativas en el promedio de vida, sin embargo, este parámetro en M. macrocopa con S. acutus cultivada en Medio Bold, fue significativamente menor que en otras dietas. Las tasas de reproducción bruta y neta de A. fissa fueron significativamente mayores con C. vulgaris cultivada en medio Bold, que con el fertilizante; estas tasas en B

  11. Development of algae-bacteria granular consortia in photo-sequencing batch reactor.

    Science.gov (United States)

    Liu, Lin; Fan, Hongyong; Liu, Yuhong; Liu, Chaoxiang; Huang, Xu

    2017-05-01

    The development and properties of algae-bacteria granular consortia, which cultivated with the algae (Chlorella and Scenedesmus) and aerobic granules, was investigated in this experiment. The results indicated that the granular consortia could be successfully developed by selection pressure control, and the algal biomass and extracellular polymeric substances (EPS) concentration in the consortia showed notable correlation with the operating parameters of reactor. The maximum specific removal rates of total nitrogen and phosphate were obtained from the granular consortia with the highest algal biomass, yet the correlation between the fatty acid methyl esters yield and the algal biomass in the consortia was not markedly observed. The seed algae maintained dominance in the phototroph community, whereas the cyanobacteria only occupied a small proportion (5.2-6.5%). Although the bacterial communities with different operational strategies showed significant difference, the dominated bacteria (Comamonadaceae, 18.79-36.25%) in the mature granular consortia were similar.

  12. New Discoveries in Study on Hydrocarbons From Thermal Degradation of Heterotrophically Yellowing Algae

    Institute of Scientific and Technical Information of China (English)

    吴庆余; 殷实; 盛国英; 傅家谟

    1994-01-01

    Green autotrophic alga Chlorella protothecoides contains a very small quantity of hydrocarbons. Heterotrophic culture of this alga results in the cells yellowing, chlorophyll disappearing, protein decreasing and lipid increasing remarkably. The quantities of hydrocarbons from them directly and from the thermal degradation of the cells at or below 200℃ are very low. These hydrocarbons are characterized by predominance of high molecular weight normal alkanes with maximum at C23-C25. When these heterotrophi-cally yellowing cells are thermally degraded at 300℃ , the aliphatic hydrocarbons increase greatly, 32 times that of the green autotrophic ones at the same temperature. Meanwhile, the low molecular weight normal alkanes with C17 as the peak become predominant instead of the original ones of high molecular weight. The actual potential of microplanktonic algae in producing hydrocarbons should be much greater than what people have recognized before.

  13. Let them eat algae

    Energy Technology Data Exchange (ETDEWEB)

    Ciferri, O.

    1981-09-24

    The blue-green alga, Spirulina appears to be one of the candidates for the solution of the global problems of energy, food and chemical feedstock supplies. The harvesting of algae from Lake Texcoco, Mexico for the making of bread was noted in the 16th century by the Spanish and over 400 years later, dried biscuits made from algae were noted in Chad. Recent investigations have shown that the alga contains a very high proportion of protein - even higher than soya beans and is of high quality. A pilot plant covering 2 hectares for culturing Spirulina in a closed system is under construction in Italy. The polyethylene tubes will function as solar collectors and so extend the production season of the algae in more temperate regions.

  14. Phytochelatin induction by selenate in Chlorella vulgaris, and regulation of effect by sulfate levels.

    Science.gov (United States)

    Simmons, Denina B D; Emery, R J Neil

    2011-02-01

    Phytochelatins (PCs) are short metal detoxification peptides made from the sulfur-rich molecule glutathione. The production of PCs by algae caused by Se exposure has never been studied, although many algae accumulate Se, forming Se-rich proteins and peptides, and higher plants have demonstrated PC production when treated with Se; therefore, a goal of the current study was to examine whether Se induces PC production in algae. Furthermore, selenate is thought to compete with sulfate in the S assimilation pathway, and sulfate therefore may have a protective effect against the toxic effects of high doses of Se in algae. Hence, the interaction of selenate and sulfate was investigated with respect to the induction of PCs. Chlorella vulgaris was cultured in media with either low (31.2 µM) or high (312 µM) concentrations of sulfate. These cultures were exposed to selenate in doses of 7, 35, and 70 nM for 48 h. In a separate treatment, Cd (890 nM) was added as a positive PC-inducing control, and one no-metal negative control was used. Total Se and Se speciation were determined, and glutathione, phytochelatin-2, and phytochelatin-3 were quantified in each of cell digests, cell medium, and cell lysates. We found that PCs and their precursor glutathione were induced by selenate as well as by a Cd control. The high concentration of sulfate was able to counter selenate-induced production of PCs and glutathione. These data support two possible mechanisms: a negative feedback system in the S assimilation pathway that affects PC production when sulfate is abundant, and competition for uptake at the ion transport level between selenate and sulfate.

  15. Antimicrobial-resistant faecal organisms in algae products marketed as health supplements

    LENUS (Irish Health Repository)

    2017-09-01

    Dietary supplements are increasingly popular in Irish society. One of these is blue-green algae which is used with a variety health benefits in mind. A batch of Chlorella powder was found to be contaminated with Salmonella species in Ireland in 2015. This prompted additional testing of a total of 8 samples of three different products (Chlorella, Spirulina and Super Greens), for other faecal flora and antimicrobial resistance in any bacteria isolated. All 8 samples cultured enteric flora such as Enterococci, Enterobacteriaceae and Clostridium species. Antimicrobial susceptibility testing revealed one isolate with extended-spectrum β-lactamase (ESBL) activity and one with carbapenemase activity. Clinicians caring for vulnerable patients should be aware of the potential risk of exposure to antimicrobial resistant bacteria associated with these products

  16. Phosphorus plays an important role in enhancing biodiesel productivity of Chlorella vulgaris under nitrogen deficiency.

    Science.gov (United States)

    Chu, Fei-Fei; Chu, Pei-Na; Cai, Pei-Jie; Li, Wen-Wei; Lam, Paul K S; Zeng, Raymond J

    2013-04-01

    To investigate the role of phosphorus in lipid production under nitrogen starvation conditions, five types of media possessing different nitrogen and phosphorus concentrations or their combination were prepared to culture Chlorella vulgaris. It was found that biomass production under nitrogen deficient condition with sufficient phosphorus supply was similar to that of the control (with sufficient nutrition), resulting in a maximum lipid productivity of 58.39 mg/L/day. Meanwhile, 31P NMR showed that phosphorus in the medium was transformed and accumulated as polyphosphate in cells. The uptake rate of phosphorus in cells was 3.8 times higher than the uptake rate of the control. This study demonstrates that phosphorus plays an important role in lipid production of C. vulgaris under nitrogen deficient conditions and implies a potential to combine phosphorus removal from wastewater with biodiesel production via microalgae.

  17. Characterization of growth and lipid production by Chlorella sp. PCH90, a microalga native to Quebec.

    Science.gov (United States)

    Abdelaziz, Ahmed Elsayed Mohamed; Ghosh, Dipankar; Hallenbeck, Patrick C

    2014-03-01

    Microalgae are being investigated as potential candidates for biodiesel production since they can be grown without competition with food production, have an inherently fast growth rate, and can have a high lipid content under different nutrient limiting conditions. However, large scale production will best be carried out with indigenous strains, well adapted to local conditions. This study reports on the characterization of the novel microalga Chlorella sp. PCH90, isolated in Quebec. Its molecular phylogeny was established and lipid production studies as a function of the initial concentrations of nitrate, phosphate, and sodium chloride were carried out using response surface methodology. Under the appropriate conditions this microalga could produce up to 36% lipid and grew well in both synthetic medium and secondary effluent from a wastewater treatment plant at both 22 and 10°C. Thus, this strain is promising for further development as a potential biofuels producer under local climatic conditions.

  18. Wastewater Treatment

    Science.gov (United States)

    ... make water safe. Effects of wastewater pollutants If wastewater is not properly treated, then the environment and human health can be negatively impacted. These impacts can include harm to fish and wildlife ... in wastewater and the potentially harmful effects these substances can ...

  19. Three stage cultivation process of facultative strain of Chlorella sorokiniana for treating dairy farm effluent and lipid enhancement.

    Science.gov (United States)

    Hena, S; Fatihah, N; Tabassum, S; Ismail, N

    2015-09-01

    Reserve lipids of microalgae are promising for biodiesel production. However, economically feasible and sustainable energy production from microalgae requires optimization of cultivation conditions for both biomass yield and lipid production of microalgae. Biomass yield and lipid production in microalgae are a contradictory problem because required conditions for both targets are different. Simultaneously, the mass cultivation of microalgae for biofuel production also depends extremely on the performance of the microalgae strains used. In this study a green unicellular microalgae Chlorella sorokiniana (DS6) isolated from the holding tanks of farm wastewater treatment plant using multi-step screening and acclimation procedures was found high-lipid producing facultative heterotrophic microalgae strain capable of growing on dairy farm effluent (DFE) for biodiesel feedstock and wastewater treatment. Morphological features and the phylogenetic analysis for the 18S rRNA identified the isolated strains. A novel three stage cultivation process of facultative strain of C. sorokiniana was examined for lipid production.

  20. Development of Bio-Oil Commodity Fuel as a Refinery Feedstock from High Impact Algae Biomass

    Energy Technology Data Exchange (ETDEWEB)

    Kastner, James [Univ. of Georgia, Athens, GA (United States). Dept. of Biochemical Engineering; Mani, Sudhagar [Univ. of Georgia, Athens, GA (United States). Dept. of Biochemical Engineering; Das, K. C. [Univ. of Georgia, Athens, GA (United States). Dept. of Biochemical Engineering; Hilten, Roger [Univ. of Georgia, Athens, GA (United States). Dept. of Biochemical Engineering; Jena, Umakanta [Desert Research Inst. (DRI), Reno, NV (United States)

    2014-11-30

    A two-stage hydrothermal liquefaction (HTL) process was developed to 1) reduce nitrogen levels in algal oil, 2) generate a nitrogen rich stream with limited inhibitors for recycle and algae cultivation, and 3) improve downstream catalytic hydrodenitrogenation and hydrodeoxygenation of the algal oil to refinery intermediates. In the first stage, low temperature HTL was conducted at 125, 175, and 225°C at holding times ranging from 1 to 30 min (time at reaction temperature). A consortium of three algal strains, namely Chlorella sorokiniana, Chlorella minutissima, and Scenedesmus bijuga were used to grow and harvest biomass in a raceway system – this consortium is called the UGA Raceway strain throughout the report. Subsequent analysis of the final harvested product indicated that only two strains predominated in the final harvest - Chlorella sorokiniana and Scenedesmus bijuga. Two additional strains representing a high protein (Spirulina platensis) and high lipid algae (Nannochloropsis) strains were also used in this study. These strains were purchased from suppliers. S. platensis biomass was provided by Earthrise Nutritionals LLC (Calipatria, CA) in dry powder form with defined properties, and was stored in airtight packages at 4°C prior to use. A Nannochloropsis paste from Reed Mariculture was purchased and used in the two-stage HTL/HDO experiments. The solids and liquids from this low temperature HTL pretreatment step were separated and analyzed, leading to the following conclusions. Overall, these results indicate that low temperature HTL (200-250°C) at short residence times (5-15 min) can be used to lyse algae cells and remove/separate protein and nitrogen before subsequent higher temperature HTL (for lipid and other polymer hydrolysis) and HDO. The significant reduction in nitrogen when coupled with low protein/high lipid algae cultivation methods at scale could significantly improve downstream catalytic HDO results. However, significant barriers and

  1. Structural organization of DNA in chlorella viruses.

    Directory of Open Access Journals (Sweden)

    Timo Wulfmeyer

    Full Text Available Chlorella viruses have icosahedral capsids with an internal membrane enclosing their large dsDNA genomes and associated proteins. Their genomes are packaged in the particles with a predicted DNA density of ca. 0.2 bp nm(-3. Occasionally infection of an algal cell by an individual particle fails and the viral DNA is dynamically ejected from the capsid. This shows that the release of the DNA generates a force, which can aid in the transfer of the genome into the host in a successful infection. Imaging of ejected viral DNA indicates that it is intimately associated with proteins in a periodic fashion. The bulk of the protein particles detected by atomic force microscopy have a size of ∼60 kDa and two proteins (A278L and A282L of about this size are among 6 basic putative DNA binding proteins found in a proteomic analysis of DNA binding proteins packaged in the virion. A combination of fluorescence images of ejected DNA and a bioinformatics analysis of the DNA reveal periodic patterns in the viral DNA. The periodic distribution of GC rich regions in the genome provides potential binding sites for basic proteins. This DNA/protein aggregation could be responsible for the periodic concentration of fluorescently labeled DNA observed in ejected viral DNA. Collectively the data indicate that the large chlorella viruses have a DNA packaging strategy that differs from bacteriophages; it involves proteins and share similarities to that of chromatin structure in eukaryotes.

  2. EVALUACIÓN DEL EFECTO DEL HIDROCARBURO FENANTRENO SOBRE EL CRECIMIENTO DE Chlorella vulgaris (CHLORELLACEAE Effect of the Hydrocarbon Phenanthrene on Chlorella vulgaris (Chlorellaceae Growth

    Directory of Open Access Journals (Sweden)

    ANGÉLICA OTEROPATERNINA

    2013-04-01

    Full Text Available Se evaluó el efecto del hidrocarburo policíclico aromático fenantreno sobre el crecimiento de la microalga Chlorella vulgaris bajo condiciones de laboratorio. Las microalgas fueron expuestas a diferentes concentraciones de fenantreno (0, 1, 10, 100, 1000 y 10000 µg/l. El tiempo de exposición fue de 72 h, determinándose diariamente la densidad algal mediante recuento en cámara de Neubauer. Se determinó la tasa promedio de crecimiento, la biomasa total y el porcentaje de inhibición de la biomasa. También se evaluó el contenido de clorofila a, al inicio y final del experimento. Los ensayos fueron realizados en recipientes de vidrio de 0,4 l, utilizando como medio de cultivo fertilizante inorgánico del complejo NPK (REMITAL® m - 17-6-18 a razón de 1 g/l. Los resultados mostraron que el fenantreno inhibió progresivamente el crecimiento de la microalga, observándose el menor crecimiento celular en el medio con la mayor concentración de fenantreno, el cual alcanzó un porcentaje de inhibición del crecimiento del 59 %. Las tasas de crecimiento diario se mantuvieron relativamente constantes en los demás tratamientos. La concentración de clorofila a, medida mediante espectrofotometría, no se afectó por las diferentes concentraciones del hidrocarburo. En conclusión, el crecimiento de la microalga C. vulgaris puede afectarse negativamente por la exposición a concentraciones nominales superiores a 1 µg/l de fenantreno.The effects of the polycyclic aromatic hydrocarbon phenanthrene on the growth of Chlorella vulgaris alga were evaluated under laboratory conditions. The algae were exposed during 72 h to different concentrations of phenanthrene (0, 1, 10, 100, 1000 and 10000 µg/l. The alga density was daily determined by a Neubauer chamber. The average growth average, total biomass and inhibition percentage of the biomass were also determined. In addition, the content of chlorophyll a was determined at the beginning and the end of the

  3. The Selective Use of Hypochlorite to Prevent Pond Crashes for Algae-Biofuel Production.

    Science.gov (United States)

    Park, Sichoon; Van Ginkel, Steven W; Pradeep, Priya; Igou, Thomas; Yi, Christine; Snell, Terry; Chen, Yongsheng

    2016-01-01

    Although algae-biofuels have many advantages including high areal productivity, algae can be preyed upon by amoebas, protozoans, ciliates, and rotifers, particularly in open pond systems. Thus, these higher organisms need to be controlled. In this study, Chlorella kessleri was used as the algal culture and Brachionus calyciflorus as the source of predation. The effect of sodium hypochlorite (bleach) was tested with the goal of totally inhibiting the rotifer while causing minor inhibition to the alga. The 24-hr LC(50) for B. calyciflorus in spring water was 0.198 mg Cl/L while the 24-hr LC(50) for C. kessleri was 0.321 mg Cl/L. However, chlorine dissipates rapidly as the algae serves as reductant. Results showed a chlorine dosage between 0.45 to 0.6 mg Cl/L and a dosing interval of two hours created the necessary chlorine concentrations to inhibit predation while letting the algae grow; thus giving algae farmers a tool to prevent pond crashes.

  4. Identification of cypermethrin induced protein changes in green algae by iTRAQ quantitative proteomics.

    Science.gov (United States)

    Gao, Yan; Lim, Teck Kwang; Lin, Qingsong; Li, Sam Fong Yau

    2016-04-29

    Cypermethrin (CYP) is one of the most widely used pesticides in large scale for agricultural and domestic purpose and the residue often seriously affects aquatic system. Environmental pollutant-induced protein changes in organisms could be detected by proteomics, leading to discovery of potential biomarkers and understanding of mode of action. While proteomics investigations of CYP stress in some animal models have been well studied, few reports about the effects of exposure to CYP on algae proteome were published. To determine CYP effect in algae, the impact of various dosages (0.001μg/L, 0.01μg/L and 1μg/L) of CYP on green algae Chlorella vulgaris for 24h and 96h was investigated by using iTRAQ quantitative proteomics technique. A total of 162 and 198 proteins were significantly altered after CYP exposure for 24h and 96h, respectively. Overview of iTRAQ results indicated that the influence of CYP on algae protein might be dosage-dependent. Functional analysis of differentially expressed proteins showed that CYP could induce protein alterations related to photosynthesis, stress responses and carbohydrate metabolism. This study provides a comprehensive view of complex mode of action of algae under CYP stress and highlights several potential biomarkers for further investigation of pesticide-exposed plant and algae.

  5. Investigation of high pressure steaming (HPS) as a thermal treatment for lipid extraction from Chlorella vulgaris.

    Science.gov (United States)

    Aguirre, Ana-Maria; Bassi, Amarjeet

    2014-07-01

    Biofuels from algae are considered a technically viable energy source that overcomes several of the problems present in previous generations of biofuels. In this research high pressure steaming (HPS) was studied as a hydrothermal pre-treatment for extraction of lipids from Chlorella vulgaris, and analysis by response surface methodology allowed finding operational points in terms of target temperature and algae concentration for high lipid and glucose yields. Within the range covered by these experiments the best conditions for high bio-crude yield are temperatures higher than 174°C and low biomass concentrations (<5 g/L). For high glucose yield there are two suitable operational ranges, either low temperatures (<105°C) and low biomass concentrations (<4 g/L); or low temperatures (<105°C) and high biomass concentrations (<110 g/L). High pressure steaming is a good hydrothermal treatment for lipid recovery and does not significantly change the fatty acids profile for the range of temperatures studied.

  6. Alleviating CTAC and Flu combined pollution damage in Chlorella vulgaris by exogenous nitric oxide.

    Science.gov (United States)

    Li, Qi; Liang, Zhijie; Ge, Fei; Xu, Yin; Yang, Liang; Zeng, Hui

    2014-02-01

    This study investigates the effect of sodium nitroprussiate (SNP), an exogenous NO-donor, on the joint toxicity of binary mixtures of cetyltrimethylammonium chloride (CTAC) and fluoranthene (Flu) (CTAC/Flu), which are representatives for surfactants and polycyclic aromatic hydrocarbons (PAHs) respectively, in a unicellular green alga Chlorella vulgaris (C. vulgaris). The results showed that the addition of low SNP (20μM) alleviated the CTAC/Flu combined pollution damage in C. vulgaris. Supplement of low SNP significantly increased the algae biomass, chlorophyll content, soluble protein content and the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) as compared to CTAC/Flu treatment alone. SNP also reduced the content of malondialdehyde (MDA) and the reactive oxygen species (ROS), as compared with CTAC/Flu treated alone. On the contrary, the above phenomena were reversed when high concentration of SNP (100μM) was added. Our study indicated that the damage of the joint action of surfactants and PAHs on hydrobios can be alleviated through protecting against oxidant substances and increasing the activity of antioxidant enzymes with an exogenous supply of NO in certain concentration range.

  7. Rapid induction of lipid droplets in Chlamydomonas reinhardtii and Chlorella vulgaris by Brefeldin A.

    Directory of Open Access Journals (Sweden)

    Sangwoo Kim

    Full Text Available Algal lipids are the focus of intensive research because they are potential sources of biodiesel. However, most algae produce neutral lipids only under stress conditions. Here, we report that treatment with Brefeldin A (BFA, a chemical inducer of ER stress, rapidly triggers lipid droplet (LD formation in two different microalgal species, Chlamydomonas reinhardtii and Chlorella vulgaris. LD staining using Nile red revealed that BFA-treated algal cells exhibited many more fluorescent bodies than control cells. Lipid analyses based on thin layer chromatography and gas chromatography revealed that the additional lipids formed upon BFA treatment were mainly triacylglycerols (TAGs. The increase in TAG accumulation was accompanied by a decrease in the betaine lipid diacylglyceryl N,N,N-trimethylhomoserine (DGTS, a major component of the extraplastidic membrane lipids in Chlamydomonas, suggesting that at least some of the TAGs were assembled from the degradation products of membrane lipids. Interestingly, BFA induced TAG accumulation in the Chlamydomonas cells regardless of the presence or absence of an acetate or nitrogen source in the medium. This effect of BFA in Chlamydomonas cells seems to be due to BFA-induced ER stress, as supported by the induction of three homologs of ER stress marker genes by the drug. Together, these results suggest that ER stress rapidly triggers TAG accumulation in two green microalgae, C. reinhardtii and C. vulgaris. A further investigation of the link between ER stress and TAG synthesis may yield an efficient means of producing biofuel from algae.

  8. Effects of iron and manganese on the formation of HAAs upon chlorinating Chlorella vulgaris

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Fei, E-mail: gefei@xtu.edu.cn [Department of Environmental Science and Engineering, Xiangtan University, Egongtang Road, Xiangtan, Hunan 411105 (China); Wu, Xiuzhen; Wang, Na; Zhu, Runliang; Wang, Tong; Xu, Yin [Department of Environmental Science and Engineering, Xiangtan University, Egongtang Road, Xiangtan, Hunan 411105 (China)

    2011-05-15

    The major objective of the present study was to investigate the role of iron and manganese on the formation of haloacetic acids (HAAs) when algae are chlorinated at different pHs. The results showed that both iron and manganese can reduce the yields of dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) on chlorinating green alga Chlorella vulgaris (C. vulgaris) at a pH range of 6.0-9.0, and the decline of DCAA and TCAA was shown to be more significant at the low pH range. At pH 6.0, DCAA and TCAA yields decreased by 44.5% and 57.3%, respectively with the addition of 0.5 mg L{sup -1} iron, and decreased 39.5% and 49.4%, respectively with the addition of 0.5 mg L{sup -1} manganese. The main reason for decreasing the yields of HAAs as shown by scanning electron microscope (SEM) is that Fe(OH){sub 3(am)} or MnO{sub 2(am)} coat the algal cells{sub ,} which then improves their agglomeration of algal cells which is also revealed by the laser particle size analysis (LPSA).

  9. Metallomics and NMR-based metabolomics of Chlorella sp. reveal the synergistic role of copper and cadmium in multi-metal toxicity and oxidative stress.

    Science.gov (United States)

    Zhang, Wenlin; Tan, Nicole G J; Fu, Baohui; Li, Sam F Y

    2015-03-01

    Industrial wastewaters often contain high levels of metal mixtures, in which metal mixtures may have synergistic or antagonistic effects on aquatic organisms. A combination of metallomics and nuclear magnetic resonance spectroscopy (NMR)-based metabolomics was employed to understand the consequences of multi-metal systems (Cu, Cd, Pb) on freshwater microalgae. Morphological characterization, cell viability and chlorophyll a determination of metal-spiked Chlorella sp. suggested synergistic effects of Cu and Cd on growth inhibition and toxicity. While Pb has no apparent effect on Chlorella sp. metabolome, a substantial decrease of sucrose, amino acid content and glycerophospholipid precursors in Cu-spiked microalgae revealed Cu-induced oxidative stress. Addition of Cd to Cu-spiked cultures induced more drastic metabolic perturbations, hence we confirmed that Cu and Cd synergistically influenced photosynthesis inhibition, oxidative stress and membrane degradation. Total elemental analysis revealed a significant decrease in K, and an increase in Na, Mg, Zn and Mn concentrations in Cu-spiked cultures. This indicated that Cu is more toxic to Chlorella sp. as compared to Cd or Pb, and the combination of Cu and Cd has a strong synergistic effect on Chlorella sp. oxidative stress induction. Oxidative stress is confirmed by liquid chromatography tandem mass spectrometry analysis, which demonstrated a drastic decrease in the GSH/GSSG ratio solely in Cu-spiked cultures. Interestingly, we observed Cu-facilitated Cd and Pb bioconcentration in Chlorella sp. The absence of phytochelatins and an increment of extracellular polymeric substances (EPS) yields in Cu-spiked cultures suggested that the mode of bioconcentration of Cd and Pb is through adsorption of free metals onto the algal EPS rather than intracellular chelation to phytochelatins.

  10. Polyphosphate during the Regreening of Chlorella vulgaris under Nitrogen Deficiency

    National Research Council Canada - National Science Library

    Chu, Fei-Fei; Shen, Xiao-Fei; Lam, Paul K S; Zeng, Raymond J

    2015-01-01

    Polyphosphate (Poly-P) accumulation has been reported in Chlorella vulgaris under nitrogen deficiency conditions with sufficient P supply, and the process has been demonstrated to have great impact on lipid productivity...

  11. Evaluation of oil-producing algae as potential biodiesel feedstock.

    Science.gov (United States)

    Zhou, XuPing; Ge, HongMei; Xia, Ling; Zhang, Delu; Hu, ChunXiang

    2013-04-01

    This study attempted to connect the dots between laboratory research and the outdoors. Chlorella sp. NJ-18 was selected among seven oil-producing algae cultivated in this study because it had the highest lipid productivity. The nitrogen and phosphorus concentrations for cultivating this Chlorella strain were optimized indoors. This strain was incubated outdoors in a 70 L photobioreactor, containing the favorable nitrogen (8.32 mM urea) and phosphorus (0.18 mM monopotassium phosphate) concentrations. Semi-continuous cultivation was performed by harvesting 30 L biomass and replacing it with fresh medium. The maximum biomass and lipid productivity acquired outdoors were 91.84 and 24.05 mg L(-1) d(-1), respectively. Furthermore, biomass productivity could be maintained at a high level throughout the cultivation process when using the semi-continuous mode, whereas it decreased dramatically in batch cultures. More than 95% of the total fatty acids obtained were C16 and C18, which are the main components for biofuel.

  12. Potential Health Effects of Enzymatic Protein Hydrolysates from Chlorella vulgaris

    OpenAIRE

    2016-01-01

    Background and Objective: Chlorella vulgaris is a multi-cellular edible algal species with abundant proteins. Extraction of high value protein fractions for pharmaceutical and nutritional applications can significantly increase the commercial value of microalga biomasses. There is no known report on the anticancer peptides derived from the Chlorella vulgaris abundant protein.Materials and Methods: This study examined the antimicrobial and anticancer effects of peptides from a hydrolyzed Chlor...

  13. Algal biofuels from wastewater treatment high rate algal ponds.

    Science.gov (United States)

    Craggs, R J; Heubeck, S; Lundquist, T J; Benemann, J R

    2011-01-01

    This paper examines the potential of algae biofuel production in conjunction with wastewater treatment. Current technology for algal wastewater treatment uses facultative ponds, however, these ponds have low productivity (∼10 tonnes/ha.y), are not amenable to cultivating single algal species, require chemical flocculation or other expensive processes for algal harvest, and do not provide consistent nutrient removal. Shallow, paddlewheel-mixed high rate algal ponds (HRAPs) have much higher productivities (∼30 tonnes/ha.y) and promote bioflocculation settling which may provide low-cost algal harvest. Moreover, HRAP algae are carbon-limited and daytime addition of CO(2) has, under suitable climatic conditions, the potential to double production (to ∼60 tonnes/ha.y), improve bioflocculation algal harvest, and enhance wastewater nutrient removal. Algae biofuels (e.g. biogas, ethanol, biodiesel and crude bio-oil), could be produced from the algae harvested from wastewater HRAPs, The wastewater treatment function would cover the capital and operation costs of algal production, with biofuel and recovered nutrient fertilizer being by-products. Greenhouse gas abatement results from both the production of the biofuels and the savings in energy consumption compared to electromechanical treatment processes. However, to achieve these benefits, further research is required, particularly the large-scale demonstration of wastewater treatment HRAP algal production and harvest.

  14. Cultivation of Nannochloropsis salina in municipal wastewater or digester centrate.

    Science.gov (United States)

    Dong, Bingfeng; Ho, Nam; Ogden, Kimberly L; Arnold, Robert G

    2014-05-01

    Meaningful use of biofuels for transportation depends on utilization of water from non-traditional, non-potable resources. Here it is hypothesized that (i) reclaimed wastewater or nutrient-rich side streams derived from municipal wastewater treatment are suitable for that purpose and (ii) use of those waters for algal growth can promote water quality through nutrient management. Experiments showed that metals levels in municipal wastewaters are unlikely to inhibit algal growth and lipid production, at least by metals tolerant microalgae like Nannochloropsis salina. Cells grew without inhibition in treated municipal wastewater or centrate derived from wastewater treatment at additions up to 75 percent v/v in their normal growth medium minus nitrogen and phosphorus. Although wastewater provides a suitable nutrient source for algal growth, not enough municipal wastewater is available to support a meaningful biofuels industry without efficient water recycling and nutrient recovery/reuse from spent algae. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Decolorization of dye wastewaters by biosorbents: a review.

    Science.gov (United States)

    Srinivasan, Asha; Viraraghavan, Thiruvenkatachari

    2010-10-01

    Dye wastewater is one of the most difficult to treat. There has been exhaustive research on biosorption of dye wastewater. It is evolving as an attractive option to supplement conventional treatment processes. This paper examines various biosorbents such as fungi, bacteria, algae, chitosan and peat, which are capable of decolorizing dye wastewaters; discusses various mechanism involved, the effects of various factors influencing dye wastewater decolorization and reviews pretreatment methods for increasing the biosorption capacity of the adsorbents. The paper examines the mismatch between strong scientific progress in the field of biosorption and lack of commercialization of research. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  16. Acclimation of microalgae to wastewater environments involves increased oxidative stress tolerance activity.

    Science.gov (United States)

    Osundeko, Olumayowa; Dean, Andrew P; Davies, Helena; Pittman, Jon K

    2014-10-01

    A wastewater environment can be particularly toxic to eukaryotic microalgae. Microalgae can adapt to these conditions but the specific mechanisms that allow strains to tolerate wastewater environments are unclear. Furthermore, it is unknown whether the ability to acclimate microalgae to tolerate wastewater is an innate or species-specific characteristic. Six different species of microalgae (Chlamydomonas debaryana, Chlorella luteoviridis, Chlorella vulgaris, Desmodesmus intermedius, Hindakia tetrachotoma and Parachlorella kessleri) that had never previously been exposed to wastewater conditions were acclimated over an 8-week period in secondary-treated municipal wastewater. With the exception of C. debaryana, acclimation to wastewater resulted in significantly higher growth rate and biomass productivity. With the exception of C. vulgaris, total chlorophyll content was significantly increased in all acclimated strains, while all acclimated strains showed significantly increased photosynthetic activity. The ability of strains to acclimate was species-specific, with two species, C. luteoviridis and P. kessleri, able to acclimate more efficiently to the stress than C. debaryana and D. intermedius. Metabolic fingerprinting of the acclimated and non-acclimated microalgae using Fourier transform infrared spectroscopy was able to differentiate strains on the basis of metabolic responses to the stress. In particular, strains exhibiting greater stress response and altered accumulation of lipids and carbohydrates could be distinguished. The acclimation to wastewater tolerance was correlated with higher accumulation of carotenoid pigments and increased ascorbate peroxidase activity.

  17. 水芹(Oenanthe javaica)浸出液对小球藻(Chlorella vulgaris)生长及超微结构的影响%Effects of Oenanthe javaica Extracts on Growth and Ultrastructure of Chlorella vulgaris

    Institute of Scientific and Technical Information of China (English)

    袁亚光; 李思宇; 宰学明; 钦佩

    2012-01-01

    Pure culture of chlorella was done in solutions different in concentration of Oenanthe javaica extracts added, to explore effects of 0. javaica extracts on growth, chlorophyll content and ultrastrueture of chlorella. Results show that in the treatment of 10 g ? L-1 O. javaica extract growth of chlorella was significantly promoted, and in the treatment of 20 g ■ L-1 O. javaica extract the number of cells and chlorophyll content of chlorella increased with a margin narrower than that in the control in the first 7 days, and afterwards, the growth was inhibited. In the treatments of 30 -50 g ? L-1 O. javaica extract, phenomenon of the inhibition became obvious on the fifth day and more obvious with the time going on and with the increasing concentration of theextract added as well. In the treatment of 40 g ? L-1 O. javaica extract, cell walls of the algae broke up and even vanished, chloroplast lamellas in the cells swelled and even disintegrated, and karyolem-mas ripped with karyoplasm extravasating. The findings indicate that O. javaica extract had an allelopathic effect on chlorella, and when low in concentration, it promotes growth of the algae, but when high, it acts reversely.%采用在不同浓度水芹(Oenanthe javaica)浸出液中纯培养小球藻(Chlorella vulgaris)的方法,研究水芹浸出液对小球藻细胞数量、叶绿素含量和藻细胞超微结构的影响.结果显示,10g· L-1水芹浸出液对小球藻的生长和叶绿素含量具有明显的促进作用;20 g·L-1水芹浸出液处理组藻细胞数量和叶绿素含量增加持续至第7天,但增幅低于对照组,7d后抑制作用增强;高浓度(30~50g· L-1)水芹浸出液对小球藻细胞数量和叶绿素含量的抑制作用在第5天开始变得显著,并随时间延长而加剧,具有浓度效应;经40g·L-1水芹浸出液处理后,小球藻细胞壁断裂甚至消失,细胞中叶绿体片层肿胀甚至解体,核膜破裂,核质外渗.结果表明水芹浸出液对小

  18. Efecto de la radiación ultravioleta B en la producción de polifenoles en la microalga marina Chlorella sp. Effect of ultraviolet B radiation on the production of polyphenols in the marine microalga Chlorella sp.

    Directory of Open Access Journals (Sweden)

    Jaime Copia

    2012-03-01

    Full Text Available Las algas marinas son una fuente importante de compuestos antioxidantes (fenoles y polifenoles, generados como mecanismos de defensa frente a factores de estrés (radiación UV, temperatura, herbívora. El objetivo de este trabajo es evaluar la estrategia de adaptación al efecto de la radiación ultravioleta B (RUV-B, 280-315 nm en la microalga marina Chlorella sp. mediante la producción de polifenoles y capacidad antioxidante total. Se expusieron cultivos de Chlorella sp. fueron expuestos a radiación UV-B (470 μW cm-2 por periodo de tiempos ascendentes. Se evaluó la capacidad antioxidante total DPPH, polifenoles totales, clorofila-a y b así como la densidad celular en cultivos expuestos y no expuestos. Los resultados indicaron que la RUV-B genera una disminución de la densidad celular en los cultivos irradiados por primera vez (1ª etapa, existiendo un aumento significativo (P Marine algae are an important source of antioxidant compounds (phenols and polyphenols, generated as defense mechanisms against stress factors (UV radiation, temperature, herbivory. The aim of this study was to evaluate the strategy of adaptation to the effect of ultraviolet B radiation (UV-B, 280-315 nm in the marine microalga Chlorella sp. through, the production of polyphenols and total antioxidant capacity. Chlorella sp. cultures were exposed to UV-B radiation (470 μW cm-2 over increasing time periods. We evaluated the total antioxidant capacity DPPH, total polyphenols, chlorophyll-a and b, and cell densities in exposed and unexposed cultures. The results indicated that UV-B caused a decrease in cell density in cultures irradiated for the first time (1st stage, with a significant increment (P < 0.05, lower than the control in the 2nd and 3rd stages only through the 4th stage (day 7, corresponding to a dose of 16,920 J m-2. The production of total phenols increased significantly (P < 0.05 for the IVth extract with respect to the control, confirming that the

  19. Characterisation Of Polysacharides And Lipids From Selected Green Algae Species By FTIR-ATR Spectroscopy

    Directory of Open Access Journals (Sweden)

    Bartošová Alica

    2015-06-01

    Full Text Available Fourier transform infrared (FTIR spectroscopy was used in this study to identify and determine spectral features of Chromochloris zofingiensis (Dönz Fucíková et L.A. Lewis (SAG 211-14, Gottingen, Germany, Acutodesmus obliguus (Turpin Hegewald (SAG 276-1, Gottingen, Germany and Chlorella sorokiniana (K. Brandt Pröschold et Darienko (SAG 211-40c, Gottingen, Germany. Polysaccharides and lipids from these three algae species were determined using Fourier Transformed Infrared Spectroscopy (FTIR with ATR accessory with diamante crystal in spectral range from 400 – 4000 cm−1 and resolution 4.

  20. Culture of Chlorella ellipsoidea in different culture media

    Directory of Open Access Journals (Sweden)

    MM Mohshina

    2017-06-01

    Full Text Available An experiment of algal culture was conducted in natural light and temperature conditions at a balcony of a room at the 2nd floor of Fisheries Faculty Building facing the north. The experiment was done to evaluate the growth of Chlorella ellipsoidea in four different media, viz, medium I (inorganic, medium II (organic, whole pulse powder extract, medium III (organic, whole lentil powder extract and medium IV (organic, whole gram powder extract under natural environment conditions during January-June, 2015. Growth rates of the algal species in four different media were found not significantly different. The alga, C. ellipsoidea attained maximum cell density of 28.89×106 cell ml-1 in the 15th day in medium I, of 30.69×106 cell ml-1 in the 13th day in medium II, of 26.18×106 cell ml-1 in the 15th day in medium III and of 21.12×106 cell ml-1 in the 13th day in medium IV. The ranges of air temperature, water temperature and light intensity were 21°C to 38°C, 23°C to 36°C and 2.28×103to 9.60×103 Lux respectively during the culture period. The average sunshine period was 5.87±2.82 hrs. Total alkalinity, free CO2, pH , NO3-N and PO4-P of algal culture media I, II, III and IV were 128, 540, 554 and 322 mgL-1; 32, 162, 102, 70 mgL-1; 7.4, 8, 7.9 and 7.9; 180, 36.6, 62.4 and 150 mgL-1, and 25.2, 48.2, 42.4 and 45.6 mgL-1, respectively. According to ANOVA of cell densities of cultures of C. ellipsoidea under treatments are not significantly different (F=1.441077. It is clear that differences between them are not significant i.e. mean algal cell densities are more or less same as differences between treatments are less than 20%.

  1. Alternative Treatment Technologies for Low-Cost Industrial and Municipal Wastewater Management

    OpenAIRE

    Hodges, Alan J.

    2017-01-01

    Roughly the same volume of water that rushes over the Niagara Falls is produced as wastewater in North America. This wastewater is treated through a variety of means to ensure that it can be safely returned to the natural ecosystem. This thesis examines two novel means for this treatment, one biological and one physical-chemical in nature, namely, Rotating Algae Biofilm Reactor treatment and expanded shale augmented coagulation-flocculation. Rotating algae biofilm reactors (RABRs) support ...

  2. Anticoagulant effect of marine algae.

    Science.gov (United States)

    Kim, Se-Kwon; Wijesekara, Isuru

    2011-01-01

    Recently, a great deal of interest has been developed in the nutraceutical and pharmaceutical industries to isolate natural anticoagulant compounds from marine resources. Among marine resources, marine algae are valuable sources of novel bioactive compounds with anticoagulant effect. Phlorotannins and sulfated polysaccharides such as fucoidans in brown algae, carrageenans in red algae, and ulvans in green algae have been recognized as potential anticoagulant agents. Therefore, marine algae-derived phlorotannins and SPs have great potential for developing as anticoagulant drugs in nutraceutical and pharmaceutical areas. This chapter focuses on the potential anticoagulant agents in marine algae and presents an overview of their anticoagulant effect. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. Co-liquefaction of micro algae with coal. 2; Bisai sorui to sekitan no kyoekika hanno. 2

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, C.; Matsui, T.; Otsuki, M.; Ikenaga, N.; Suzuki, T. [Kansai University, Osaka (Japan). Faculty of Engineering

    1996-10-28

    For the removal and recycle of CO2, a global warming gas, utilization of photosynthesis by micro algae is investigated. Formed micro algae are decomposed into CO2, H2O and CH4 again, which does not result in the permanent fixation. For the effective utilization of these micro algae, creation of petroleum alternate energy was tried through the co-liquefaction of micro algae with coal. Were investigated influences of the reaction temperature during the co-liquefaction and influences of catalysts, such as Fe(CO)5-S, Ru(CO)12, and Mo(CO)6-S, which are effective for the coal liquefaction. Micro algae, such as chlorella, spirulina, and littorale, and Yallourn brown coal were tested. It was found that co-liquefaction of micro algae with coal can be successfully proceeded under the same conditions as the liquefaction of coal. The oil yield obtained from the co-liquefaction in the presence of Fe(CO)5-S, an effective catalyst for coal liquefaction, agreed appropriately with the arithmetical mean value from separate liquefaction of coal and micro algae. It was suggested that pyrrhotite, an active species for coal liquefaction, was sufficiently formed by increasing the addition of sulfur. 2 refs., 7 figs., 1 tab.

  4. The research on rapid proliferation of ChLoreLLa py renoidosa%小球藻快速增殖技术研究

    Institute of Scientific and Technical Information of China (English)

    张旭; 钟鸿干; 孙杨; 裴明海; 王辉

    2014-01-01

    ChLoreLLa pyrenoidosais one kind of common algae .Because of the strong photosynthesis and the characteristic of easy to digest ,can fertilize and transfer the water in the breeding process ,it plays a very important role in the cultivations of the fish ,the shrimp ,the crabs and the shellfish .The result shows that ChLoreLLa pyrenoidosa can proliferate more rapid with the extracted liquid from Eupatorium odoratum than without it .The discovery could meet the need of ChLoreLLa pyrenoidosa rapid proliferation .%小球藻(ChLoreLLa pyrenoidosa)作为渔业生产常用藻,因其强大的光合作用和易于消化的特性,在鱼、虾、蟹、贝的养殖过程中起着很好的肥水和调水的作用。本研究通过实验证明,在飞机草(Eup atorium od-oratum)浸提液作用下,小球藻的增殖速度明显高于未做添加组。可满足小球藻大量、快速增殖的生产需求。

  5. Nitrous Oxide (N2O) production in axenic Chlorella vulgaris microalgae cultures: evidence, putative pathways, and potential environmental impacts

    Science.gov (United States)

    Guieysse, B.; Plouviez, M.; Coilhac, M.; Cazali, L.

    2013-10-01

    Using antibiotic assays and genomic analysis, this study demonstrates nitrous oxide (N2O) is generated from axenic Chlorella vulgaris cultures. In batch assays, this production is magnified under conditions favouring intracellular nitrite accumulation, but repressed when nitrate reductase (NR) activity is inhibited. These observations suggest N2O formation in C. vulgaris might proceed via NR-mediated nitrite reduction into nitric oxide (NO) acting as N2O precursor via a pathway similar to N2O formation in bacterial denitrifiers, although NO reduction to N2O under oxia remains unproven in plant cells. Alternatively, NR may reduce nitrite to nitroxyl (HNO), the latter being known to dimerize to N2O under oxia. Regardless of the precursor considered, an NR-mediated nitrite reduction pathway provides a unifying explanation for correlations reported between N2O emissions from algae-based ecosystems and NR activity, nitrate concentration, nitrite concentration, and photosynthesis repression. Moreover, these results indicate microalgae-mediated N2O formation might significantly contribute to N2O emissions in algae-based ecosystems (e.g. 1.38-10.1 kg N2O-N ha-1 yr-1 in a 0.25 m deep raceway pond operated under Mediterranean climatic conditions). These findings have profound implications for the life cycle analysis of algae biotechnologies and our understanding of the global biogeochemical nitrogen cycle.

  6. Nitrous Oxide (N2O production in axenic Chlorella vulgaris microalgae cultures: evidence, putative pathways, and potential environmental impacts

    Directory of Open Access Journals (Sweden)

    B. Guieysse

    2013-10-01

    Full Text Available Using antibiotic assays and genomic analysis, this study demonstrates nitrous oxide (N2O is generated from axenic Chlorella vulgaris cultures. In batch assays, this production is magnified under conditions favouring intracellular nitrite accumulation, but repressed when nitrate reductase (NR activity is inhibited. These observations suggest N2O formation in C. vulgaris might proceed via NR-mediated nitrite reduction into nitric oxide (NO acting as N2O precursor via a pathway similar to N2O formation in bacterial denitrifiers, although NO reduction to N2O under oxia remains unproven in plant cells. Alternatively, NR may reduce nitrite to nitroxyl (HNO, the latter being known to dimerize to N2O under oxia. Regardless of the precursor considered, an NR-mediated nitrite reduction pathway provides a unifying explanation for correlations reported between N2O emissions from algae-based ecosystems and NR activity, nitrate concentration, nitrite concentration, and photosynthesis repression. Moreover, these results indicate microalgae-mediated N2O formation might significantly contribute to N2O emissions in algae-based ecosystems (e.g. 1.38–10.1 kg N2O-N ha−1 yr−1 in a 0.25 m deep raceway pond operated under Mediterranean climatic conditions. These findings have profound implications for the life cycle analysis of algae biotechnologies and our understanding of the global biogeochemical nitrogen cycle.

  7. Co-culturing Chlorella minutissima with Escherichia coli can increase neutral lipid production and improve biodiesel quality.

    Science.gov (United States)

    Higgins, Brendan T; Labavitch, John M; VanderGheynst, Jean S

    2015-09-01

    Lipid productivity and fatty acid composition are important metrics for the production of high quality biodiesel from algae. Our previous results showed that co-culturing the green alga Chlorella minutissima with Escherichia coli under high-substrate mixotrophic conditions enhanced both culture growth and crude lipid content. To investigate further, we analyzed neutral lipid content and fatty acid content and composition of axenic cultures and co-cultures produced under autotrophic and mixotrophic conditions. We found that co-culturing C. minutissima with E. coli under high substrate conditions (10 g/L) increased neutral lipid content 1.9- to 3.1-fold and fatty acid content 1.5- to 2.6-fold compared to equivalent axenic C. minutissima cultures. These same co-cultures also exhibited a significant fatty acid shift away from trienoic and toward monoenoic fatty acids thereby improving the quality of the synthesized fatty acids for biodiesel production. Further investigation suggested that E. coli facilitates substrate uptake by the algae and that the resulting growth enhancement induces a nitrogen-limited condition. Enhanced carbon uptake coupled with nitrogen limitation is the likely cause of the observed neutral lipid accumulation and fatty acid profile changes.

  8. Global analysis of Chlorella variabilis NC64A mRNA profiles during the early phase of Paramecium bursaria chlorella virus-1 infection.

    Directory of Open Access Journals (Sweden)

    Janet M Rowe

    Full Text Available The PBCV-1/Chlorella variabilis NC64A system is a model for studies on interactions between viruses and algae. Here we present the first global analyses of algal host transcripts during the early stages of infection, prior to virus replication. During the course of the experiment stretching over 1 hour, about a third of the host genes displayed significant changes in normalized mRNA abundance that either increased or decreased compared to uninfected levels. The population of genes with significant transcriptional changes gradually increased until stabilizing at 40 minutes post infection. Functional categories including cytoplasmic ribosomal proteins, jasmonic acid biosynthesis and anaphase promoting complex/cyclosomes had a significant excess in upregulated genes, whereas spliceosomal snRNP complexes and the shikimate pathway had significantly more down-regulated genes, suggesting that these pathways were activated or shut-down in response to the virus infection. Lastly, we examined the expression of C. varibilis RNA polymerase subunits, as PBCV-1 transcription depends on host RNA polymerases. Two subunits were up-regulated, RPB10 and RPC34, suggesting that they may function to support virus transcription. These results highlight genes and pathways, as well as overall trends, for further refinement of our understanding of the changes that take place during the early stages of viral infection.

  9. Algae as an electron donor promoting sulfate reduction for the bioremediation of acid rock drainage.

    Science.gov (United States)

    Ayala-Parra, Pedro; Sierra-Alvarez, Reyes; Field, Jim A

    2016-11-05

    This study assessed bioremediation of acid rock drainage in simulated permeable reactive barriers (PRB) using algae, Chlorella sorokiniana, as the sole electron donor for sulfate-reducing bacteria. Lipid extracted algae (LEA), the residues of biodiesel production, were compared with whole cell algae (WCA) as an electron donor to promote sulfate-reducing activity. Inoculated columns containing anaerobic granular sludge were fed a synthetic medium containing H2SO4 and Cu(2+). Sulfate, sulfide, Cu(2+) and pH were monitored throughout the experiment of 123d. Cu recovered in the column packing at the end of the experiment was evaluated using sequential extraction. Both WCA and LEA promoted 80% of sulfate removal (12.7mg SO4(2-) d(-1)) enabling near complete Cu removal (>99.5%) and alkalinity generation raising the effluent pH to 6.5. No noteworthy sulfate reduction, alkalinity formation and Cu(2+) removal were observed in the endogenous control. In algae amended-columns, Cu(2+) was precipitated with biogenic H2S produced by sulfate reduction. Formation of CuS was evidenced by sequential extraction and X-ray diffraction. LEA and WCA provided similar levels of electron donor based on the COD balance. The results demonstrate an innovative passive remediation system using residual algae biomass from the biodiesel industry.

  10. Chlorella vulgaris Attenuates Dermatophagoides Farinae-Induced Atopic Dermatitis-Like Symptoms in NC/Nga Mice

    Directory of Open Access Journals (Sweden)

    Heerim Kang

    2015-09-01

    Full Text Available Atopic dermatitis (AD is a chronic and inflammatory skin disease that can place a significant burden on quality of life for patients. AD most frequently appears under the age of six and although its prevalence is increasing worldwide, therapeutic treatment options are limited. Chlorella vulgaris (CV is a species of the freshwater green algae genus chlorella, and has been reported to modulate allergy-inducible factors when ingested. Here, we examined the effect of CV supplementation on AD-like symptoms in NC/Nga mice. CV was orally administrated for six weeks while AD-like symptoms were induced via topical application of Dermatophagoides farinae extract (DFE. CV treatment reduced dermatitis scores, epidermal thickness, and skin hydration. Histological analysis also revealed that CV treatment reduced DFE-induced eosinophil and mast cell infiltration into the skin, while analysis of serum chemokine levels indicated that CV treatment downregulated thymus- and activation-regulated chemokine (TARC and macrophage-derived chemokine (MDC levels. In addition, CV treatment downregulated mRNA expression levels of IL-4 and IFN-γ. Taken together, these results suggest that CV extract may have potential as a nutraceutical ingredient for the prevention of AD.

  11. INMOVILIZACIÓN DE LAS MICROALGAS Scenedesmus ovalternus (Scenedesmaceae Y Chlorella vulgaris (Chlorellaceae EN ESFERAS DE ALGINATO DE CALCIO

    Directory of Open Access Journals (Sweden)

    Mario Andrés FORERO-CUJIÑO

    2016-01-01

    Full Text Available En este trabajo se describe la técnica de inmovilización de microalgas en esferas de alginato de calcio. Se emplearon las especies Scenedesmus ovalternus y Chlorella vulgaris , se determinó la estabilidad de las esferas, la cinética de crecimiento y la concentración de las microalgas en el interior de las esferas. Chlorella vulgaris alcanzó mayores densidades poblacionales y tasas de crecimiento más altas cuando se inmovilizó en concentraciones del 10 % v/v con el alginato (1,31*10 6 cél/ml. Para Scenedesmus ovalternus se observó una mayor densidad poblacional y una mayor tasa de crecimiento cuando se inmovilizó en concentraciones del 20 % v/v (7,06*10 5 cél/ml. Estos resultados son útiles para aplicaciones prácticas de las algas encapsuladas, tales como el biomonitoreo o la biorremediación.

  12. Chlorella vulgaris Attenuates Dermatophagoides Farinae-Induced Atopic Dermatitis-Like Symptoms in NC/Nga Mice.

    Science.gov (United States)

    Kang, Heerim; Lee, Chang Hyung; Kim, Jong Rhan; Kwon, Jung Yeon; Seo, Sang Gwon; Han, Jae Gab; Kim, Byung Gon; Kim, Jong-Eun; Lee, Ki Won

    2015-09-02

    Atopic dermatitis (AD) is a chronic and inflammatory skin disease that can place a significant burden on quality of life for patients. AD most frequently appears under the age of six and although its prevalence is increasing worldwide, therapeutic treatment options are limited. Chlorella vulgaris (CV) is a species of the freshwater green algae genus chlorella, and has been reported to modulate allergy-inducible factors when ingested. Here, we examined the effect of CV supplementation on AD-like symptoms in NC/Nga mice. CV was orally administrated for six weeks while AD-like symptoms were induced via topical application of Dermatophagoides farinae extract (DFE). CV treatment reduced dermatitis scores, epidermal thickness, and skin hydration. Histological analysis also revealed that CV treatment reduced DFE-induced eosinophil and mast cell infiltration into the skin, while analysis of serum chemokine levels indicated that CV treatment downregulated thymus- and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC) levels. In addition, CV treatment downregulated mRNA expression levels of IL-4 and IFN-γ. Taken together, these results suggest that CV extract may have potential as a nutraceutical ingredient for the prevention of AD.

  13. PROPAGACIÓN DE LA MICROALGA Chlorella sp. EN CULTIVO POR LOTE: CINÉTICA DEL CRECIMIENTO CELULAR

    Directory of Open Access Journals (Sweden)

    Cherlys Infante

    2012-01-01

    Full Text Available En este trabajo, se estudia el crecimiento de Chlorella sp., un alga microscópica, ampliamente distribuida en aguas marinas, con el fin de observar su comportamiento en cultivo por lote. El diseño experimental contempló la obtención de la biomasa de la microalga, utilizando un medio preparado con sales inorgánicas. Se obtuvo información acerca de la reproducibilidad de los ensayos realizados, estableciendo que se trata de un microorganismo de fácil propagación. Este resultado a su vez posibilita la aplicación de la microalga a diferentes estrategias para la remoción de sustancias nocivas presentes en los ecosistemas. El cultivo por lotes resulta adecuado para la obtención de biomasa de Chlorella sp observándose un ajuste lineal para la cinética de crecimiento. Los resultados obtenidos son una contribución al proyecto de investigación en el área de biosorción, que actualmente se desarrolla en conjunto la Universidad de Cartagena y la Universidad del Atlántico (Colombia.

  14. Wastewater Collection.

    Science.gov (United States)

    Chatterjee, Samar; And Others

    1978-01-01

    Presents a literature review of wastewater collection systems and components. This review covers: (1) planning, (2) construction; (3) sewer system evaluation; (4) maintenance; (5) rehabilitation; (6) overview prevention; and (7) wastewater pumping. A list of 111 references is also presented. (HM)

  15. Performance assessment of biofuel production in an algae-based remediation system.

    Science.gov (United States)

    Wuang, Shy Chyi; Luo, Yanpei Darren; Wang, Simai; Chua, Pei Qiang Danny; Tee, Pok Siang

    2016-03-10

    The production of biofuel from microalgae has been an area of great interest as microalgae have higher productivities than land plants, and certain species have high lipid constituents which are the major feedstock for biodiesel production. One way to enhance the economic feasibility of algal-based biofuel is to couple it with waste remediation. This study investigated the technical feasibility of cultivating Chlorella sp. and Nannochloropsis sp. with fish water for biofuel production. The remediation potential of Chlorella sp. was found to be higher but the lipid yield is lower, when compared to Nannochloropsis sp. Lipid productivities were found to be similar for both types of algae at 1.1-1.3mgL(-1)h(-1). The fatty acid profiles of the obtained lipids were found suitable for biofuel production, and the calorific values were high at 30-32MJ/kg. The results provide insights into lipid production in Chlorella sp. and Nannochloropsis sp., when coupled with waste remediation. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Bioenergy from wastewater-based biomass

    Directory of Open Access Journals (Sweden)

    Ronald C. Sims

    2016-01-01

    Full Text Available The U.S. Department of Energy (DOE has stated that biomass is the only renewable resource that can supplant petroleum-based liquid transportation fuels in the near term. Wastewater is beginning to be viewed as a potential resource that can be exploited for biomass production and conversion to bioenergy. We suggest that using wastewater from municipalities and industries as a resource for cultivating biomass and combining wastewater treatment with the production of biomass for bioenergy would provide benefits to both industries. Two waste-based biomass production systems that currently have large nationwide infrastructures include: (1 wastewater treatment systems that can be used to cultivate algae biomass, and (2 land application/treatment systems for non-food terrestrial biomass. These existing infrastructures could be used in the relatively near future for waste-based biomass production and conversion to bioenergy, thereby reducing capital costs and scalability challenges while making a contribution to energy independence and national security.

  17. Algae of economic importance that accumulate cadmium and lead: a review

    Directory of Open Access Journals (Sweden)

    Priscila O. Souza

    2012-08-01

    Full Text Available Currently, algae and algae products are extensively applied in the pharmaceutical, cosmetic and food industries. Algae are the main organisms that take up and store heavy metals. Therefore, the use of compounds derived from algae by the pharmaceutical industry should be closely monitored for possible contamination. The pollution generated by heavy metals released by industrial and domestic sources causes serious changes in the aquatic ecosystem, resulting in a loss of biological diversity and a magnification and bioaccumulation of toxic agents in the food chain. Since algae are at the bottom of the aquatic food chain, they are the most important vector for transfer of pollution to upper levels of the trophic chain in aquatic environments. Moreover, microalgae are also used for the bioremediation of wastewater, a process that does not produce secondary pollution, that enables efficient recycling of nutrients and that generates biomass useful for the production of bioactive compounds and biofuel.

  18. Differential lipid and fatty acid profiles of photoautotrophic and heterotrophic Chlorella zofingiensis: assessment of algal oils for biodiesel production.

    Science.gov (United States)

    Liu, Jin; Huang, Junchao; Sun, Zheng; Zhong, Yujuan; Jiang, Yue; Chen, Feng

    2011-01-01

    The objective of this study was to document and compare the lipid class and fatty acid composition of the green microalga Chlorella zofingiensis cultivated under photoautotrophic and heterotrophic conditions. Compared with photoautotrophic cells, a 900% increase in lipid yield was achieved in heterotrophic cells fed with 30 g L(-1) of glucose. Furthermore heterotrophic cells accumulated predominantly neutral lipids (NL) that accounted for 79.5% of total lipids with 88.7% being triacylglycerol (TAG); whereas photoautotrophic cells contained mainly the membrane lipids glycolipids (GL) and phospholipids (PL). Together with the much higher content of oleic acid (C18:1) (35.2% of total fatty acids), oils from heterotrophic C. zofingiensis appear to be more feasible for biodiesel production. Our study highlights the possibility of using heterotrophic algae for producing high quality biodiesel.

  19. Pretreatment for simultaneous production of total lipids and fermentable sugars from marine alga, Chlorella sp.

    Science.gov (United States)

    Lee, Choon-Geun; Kang, Do-Hyung; Lee, Dong-Bog; Lee, Hyeon-Yong

    2013-11-01

    The goal of this study was to determine the optimal pretreatment process for the extraction of lipids and reducing sugars to facilitate the simultaneous production of biodiesel and bioethanol from the marine microalga Chorella sp. With a single pretreatment process, the optimal ultrasonication pretreatment process was 10 min at 47 KHz, and extraction yields of 6.5 and 7.1 (percentage, w/w) of the lipids and reducing sugars, respectively, were obtained. The optimal microwave pretreatment process was 10 min at 2,450 MHz, and extraction yields of 6.6 and 7.0 (percentage, w/w) of the lipids and reducing sugars, respectively, were obtained. Lastly, the optimal high-pressure homogenization pretreatment process was two cycles at a pressure of 20,000 psi, and extraction yields of 12.5 and 12.8 (percentage, w/w) of the lipids and reducing sugars, respectively, were obtained. However, because the single pretreatment processes did not markedly improve the extraction yields compared to the results of previous studies, a combination of two pretreatment processes was applied. The yields of lipids and reducing sugars from the combined application of the high-pressure homogenization process and the microwave process were 24.4 and 24.9 % (w/w), respectively, which was up to three times greater than the yields obtained using the single pretreatment processes. Furthermore, the oleic acid content, which is a fatty acid suitable for biodiesel production, was 23.39 % of the fatty acids (w/w). The contents of glucose and xylose, which are among the fermentable sugars useful for bioethanol production, were 77.5 and 13.3 % (w/w) of the fermentable sugars, respectively, suggesting the possibility of simultaneously producing biodiesel and bioethanol. Based on the results of this study, the combined application of the high-pressure homogenization and microwave pretreatment processes is the optimal method to increase the extraction yields of lipids and reducing sugars that are essential for the simultaneous production of biodiesel and bioethanol.

  20. Responses of marine unicellular algae to brominated organic compounds in six growth media

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, G.E.; Yoder, M.J.; McLaughlin, L.L.; Lores, E.M.

    1987-12-01

    Marine unicellular algae, Skeletonema costatum, Thalassiosira pseudonana, and Chlorella sp. were exposed to the industrial brominated compounds tetrabromobisphenol A, decabromobiphenyloxide (DBBO), hexabromocyclododecane (HBCD), pentabromomethylbenzene (PBMB), pentabromoethylbenzene (PBEB), and the herbicide bromoxynil (BROM), in six algal growth media. High concentrations of DBBO (1 mg liter-1), PBMB (1 mg liter-1), and PBEB (0.5 mg liter-1) reduced growth by less than 50%. EC50s of the other compounds varied with growth medium, with high EC50/low EC50 ratios between 1.3 and 9.9. Lowest EC50s, 9.3 to 12.0 micrograms liter-1, were obtained with S. costatum and HBCD. It is concluded that responses to toxicants in different media are the results of interactions among algae, growth medium, toxicant, and solvent carrier.

  1. Trophic transfer potential of aluminium oxide nanoparticles using representative primary producer (Chlorella ellipsoides) and a primary consumer (Ceriodaphnia dubia)

    Energy Technology Data Exchange (ETDEWEB)

    Pakrashi, Sunandan; Dalai, Swayamprava; Chandrasekaran, Natarajan; Mukherjee, Amitava, E-mail: amit.mookerjea@gmail.com

    2014-07-01

    Highlights: • Trophic transfer of alumina nanoparticles using Chlorella ellipsoides and Ceriodaphnia dubia. • Subtle alterations in the feeding behaviour of the daphnids. • Disruption the energy flow through the food chain. • Transmission electron microscopy validated the disrupted feeding behaviour. - Abstract: The transfer of nanoparticles through the food chain can lead to bioaccumulation and biomagnification resulting in a long term negative impact on the ecosystem functions. The primary objective of this study was evaluation of aluminium oxide nanoparticles transfer from primary producers to primary consumers. A simple set up consisting of a primary producer (Chlorella ellipsoides) and a primary consumer (Ceriodaphnia dubia) was used. Here, C. ellipsoides were exposed to the varying concentrations of the nanoparticles ranging from 20 to 120 μg/mL (196 to 1176 μM) for 48 h and the infested algal cells were used as the feed to C. dubia. The bioaccumulation of the nanoparticles into the daphnids was noted and the biomagnification factors were computed. The exposure was noted to cause subtle alterations in the feeding behaviour of the daphnids. This might have long term consequences in the energy flow through the food chain. The reproductive behaviour of the daphnids remained unaffected upon exposure to nanoparticle infested algal feed. Distinct observations at ultra-structural scale using transmission electron microscopy provided visual evidences for the disrupted feeding behaviour upon exposure to nanoparticle treated algae. Internalization of nanoparticle like inclusion bodies in the intracellular space of algae was also detected. The findings were further substantiated by a detailed analysis of hydrodynamic stability, bioavailability and dissolution of ions from the nanoparticles over the exposure period. Altogether, the study brings out the first of its kind of observation of trophic transfer potential/behaviour of aluminium oxide nanoparticles and

  2. Blue-green algae

    Science.gov (United States)

    ... about the use of blue-green algae during pregnancy and breast-feeding. Stay on the safe side and avoid use. "Auto-immune diseases" such as multiple sclerosis (MS), lupus (systemic lupus erythematosus, SLE), rheumatoid arthritis (RA), pemphigus vulgaris (a skin ...

  3. Oxidation pond for municipal wastewater treatment

    Science.gov (United States)

    Butler, Erick; Hung, Yung-Tse; Suleiman Al Ahmad, Mohammed; Yeh, Ruth Yu-Li; Liu, Robert Lian-Huey; Fu, Yen-Pei

    2017-03-01

    This literature review examines process, design, and cost issues related to using oxidation ponds for wastewater treatment. Many of the topics have applications at either full scale or in isolation for laboratory analysis. Oxidation ponds have many advantages. The oxidation pond treatment process is natural, because it uses microorganisms such as bacteria and algae. This makes the method of treatment cost-effective in terms of its construction, maintenance, and energy requirements. Oxidation ponds are also productive, because it generates effluent that can be used for other applications. Finally, oxidation ponds can be considered a sustainable method for treatment of wastewater.

  4. Nutrient removal by Chlorella vulgaris F1068 under cetyltrimethyl ammonium bromide induced hormesis.

    Science.gov (United States)

    Zhou, Qiongzhi; Li, Feng; Ge, Fei; Liu, Na; Kuang, Yangduo

    2016-10-01

    Toxicants are generally harmful to biotechnology in wastewater treatment. However, trace toxicant can induce microbial hormesis, but to date, it is still unknown how this phenomenon affects nutrient removal during municipal wastewater treatment process. Therefore, this study focused on the effects of hormesis induced by cetyltrimethyl ammonium bromide (CTAB), a representative quaternary ammonium cationic surfactant, on nutrient removal by Chlorella vulgaris F1068. Results showed that when the concentration of CTAB was less than 10 ng/L, the cellular components chlorophyll a, proteins, polysaccharides, and total lipids increased by 10.11, 58.17, 38.78, and 11.87 %, respectively, and some enzymes in nutrient metabolism of algal cells, such as glutamine synthetase (GS), acid phosphatase (ACP), H(+)-ATPase, and esterase, were also enhanced. As a result, the removal efficiencies of ammonia nitrogen (NH4 (+)) and total phosphorus (TP) increased by 14.66 and 8.51 %, respectively, compared to the control during a 7-day test period. The underlying mechanism was mainly due to an enhanced photosynthetic activity of C. vulgaris F1068 indicated by the increase in chlorophyll fluorescence parameters (the value of Fv/Fm, ΦII, Fv/Fo, and rETR increased by 12.99, 7.56, 25.59, and 8.11 %, respectively) and adenylate energy charge (AEC) (from 0.68 to 0.72). These results suggest that hormesis induced by trace toxicants could enhance the nutrient removal, which would be further considered in the design of municipal wastewater treatment processes. Graphical abstract The schematic mechanism of C. vulgaris F1068 under CTAB induced hormesis. Green arrows ( ) represent the increase and the red arrow ( ) represents the decrease.

  5. Isolation and algae-lysing characteristics of the algicidal bacterium B5

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Water blooms have become a worldwide environmental problem. Recently, algicidal bacteria have attracted wide attention as possible agents for inhibiting algal water blooms. In this study, one strain of algicidal bacterium B5 was isolated from activated sludge. On the basis of analysis of its physiological characteristics and 16S rDNA gene sequence, it was identified as Bacillus fusiformis. Its algae-lysing characteristics on Microcystis aeruginosa, Chlorella and Scenedesmus were tested. The results showed that: (1) the algicidal bacterium B5 is a Gram-negative bacterium. The 16S rDNA nucleotide sequence homology of strain B5 with 2 strains of B. fusiformis reached 99.86%, so B5 was identified as B. fusiformis; (2) the algal-lysing effects of the algicidal bacterium B5 on M. aeruginosa, Chlorella and Scenedesmus were pronounced. The initial bacterial and algal cell densities strongly influence the removal rates of chlorophyll-a. The greater the initial bacterial cell density, the faster the degradation of chlorophyll-a. The greater the initial algal cell density, the slower the degradation of chlorophyll-a. When the bacterial cell density was 3.6 × 107 cells/ml, nearly 90% of chlorophyll-a was removed. When the chlorophyll-a concentration was less than 550 μg/L, about 70 % was removed; (3) the strain B5 lysed algae not directly but by secreting metabolites and these metabolites could bear heat treatment.

  6. Harvesting fresh water and marine algae by magnetic separation: screening of separation parameters and high gradient magnetic filtration.

    Science.gov (United States)

    Cerff, Martin; Morweiser, Michael; Dillschneider, Robert; Michel, Aymeé; Menzel, Katharina; Posten, Clemens

    2012-08-01

    In this study, the focus is on magnetic separation of fresh water algae Chlamydomonas reinhardtii and Chlorella vulgaris as well as marine algae Phaeodactylum tricornutum and Nannochloropsis salina by means of silica-coated magnetic particles. Due to their small size and low biomass concentrations, harvesting algae by conventional methods is often inefficient and cost-consuming. Magnetic separation is a powerful tool to capture algae by adsorption to submicron-sized magnetic particles. Hereby, separation efficiency depends on parameters such as particle concentration, pH and medium composition. Separation efficiencies of >95% were obtained for all algae while maximum particle loads of 30 and 77 g/g were measured for C. reinhardtii and P. tricornutum at pH 8 and 12, respectively. This study highlights the potential of silica-coated magnetic particles for the removal of fresh water and marine algae by high gradient magnetic filtration and provides critical discussion on future improvements. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Wastewater reuse

    Directory of Open Access Journals (Sweden)

    Milan R. Radosavljević

    2013-12-01

    Full Text Available Water scarcity and water pollution are some of the crucial issues that must be addressed within local and global perspectives. One of the ways to reduce the impact of water scarcity  and to minimizine water pollution is to expand water and wastewater reuse. The local conditions including regulations, institutions, financial mechanisms, availability of local technology and stakeholder participation have a great influence on the decisions for wastewater reuse. The increasing awareness of food safety and the influence of the countries which import food are influencing policy makers and agriculturists to improve the standards of wastewater reuse in agriculture. The environmental awareness of consumers has been putting pressure on the producers (industries to opt for environmentally sound technologies including those which conserve water and reduce the level of pollution. It may be observed that we have to move forwards to implement strategies and plans for wastewater reuse. However, their success and sustainability will depend on political will, public awareness and active support from national and international agencies to create favorable    environment for the promotion of environmentally sustainable technologies. Wastewater treatment has a long history, especially in agriculture, but also in industry and households. Poor quality of wastewater can pose a significant risk to the health of farmers and users of agricultural products. The World Health Organization (WHO is working on a project for the reuse of wastewater in agriculture. To reduce effects of human activities to the minimum, it is necessary to provide such technical and technological solutions that would on the one hand ensure complying with  the existing regulations and legislation, and on the other hand provide economically viable systems as seen through investments and operating costs. The use of wastewater The practice of using wastewater varies from country to country. Its

  8. Wastewater Districts

    Data.gov (United States)

    Vermont Center for Geographic Information — The Wastewater districts layer is part of a larger dataset that contains administrative boundaries for Vermont's Agency of Natural Resources. The dataset includes...

  9. Wastewater Treatment.

    Science.gov (United States)

    Zoltek, J., Jr.; Melear, E. L.

    1978-01-01

    Presents the 1978 literature review of wastewater treatment. This review covers: (1) process application; (2) coagulation and solids separation; (3) adsorption; (4) ion exchange; (5) membrane processes; and (6) oxidation processes. A list of 123 references is also presented. (HM)

  10. Photoautotrophic Microalgae Screening for Tertiary Treatment of Livestock Wastewater and Bioresource Recovery

    Directory of Open Access Journals (Sweden)

    Ji-Yeon Kim

    2017-03-01

    Full Text Available Photoautotrophic microalgae offer high promise for a tertiary treatment of livestock wastewater owing to their rapid growth and nutrient uptake. To screen better microalga for the tertiary treatment, batch photobioreactor tests were conducted using Chlorella emersonii, Chlorella sorokiniana, and Botryococcus braunii. This study evaluated their specific growth rates, CO2 utilization rates, and nutrient removal rates to provide appropriate selection guidelines. Based on statistical comparisons, results indicate that selecting the right microalgae was the key to success in the tertiary treatment since each microalga responded differently, even under the same light, temperature, and nutrient conditions. Among the tested species, Chlorella emersonii was found to present the fastest photoautotrophic growth, total inorganic carbon (TIC utilization, and nutrient removal for livestock wastewater treatment. Regression results identified that its specific growth and total nitrogen removal rates were as high as 0.51 day−1 and 0.18 day−1, respectively. Estimated TIC utilization over the supplied TIC was much higher (~34% than those of others (11%–18%. This systemic evaluation of rate-limiting factors provides a quantitative understanding of the kinetic-based selection strategy of microalgae to polish livestock wastewater with better effluent quality.

  11. Catalytic hydrothermal gasification of algae for hydrogen production: composition of reaction products and potential for nutrient recycling.

    Science.gov (United States)

    Onwudili, Jude A; Lea-Langton, Amanda R; Ross, Andrew B; Williams, Paul T

    2013-01-01

    Chlorella vulgaris, Spirulina platensis and Saccharina latissima were processed under supercritical water gasification conditions at 500 °C, 36 MPa in an Inconel batch reactor for 30 min in the presence/absence of NaOH and/or Ni-Al(2)O(3). Hydrogen gas yields were more than two times higher in the presence of NaOH than in its absence and tar yields were reduced by up to 71%. Saccharina, a carbohydrate-rich macro-alga, gave the highest hydrogen gas yields of 15.1 mol/kg. The tars from all three algae contained aromatic compounds, including phenols, alkyl benzenes and polycyclic aromatic hydrocarbons as well as heterocyclic nitrogen compounds. Tars from Chlorella and Spirulina contained high yields of pyridines, pyrroles, indoles and pyrimidines. Up to 97% TOC removal were achieved in the process waters from the gasification of the algae. Analyses for specific nutrients in the process waters indicated that the process waters from Saccharina could potentially be used for microalgae cultivation.

  12. Growth-inhibitory and metal-binding proteins in Chlorella vulgaris exposed to cadmium or zinc

    Energy Technology Data Exchange (ETDEWEB)

    Huang Zhiyong [College of Bioengineering, Jimei University, Xiamen, 361021 (China)], E-mail: zhyhuang@jmu.edu.cn; Li Lianping; Huang Gaoling [College of Bioengineering, Jimei University, Xiamen, 361021 (China); Yan Qingpi [College of fisheries, Jimei University, Xiamen, 361021 (China); Shi Bing; Xu Xiaoqin [Xiamen Products Quality Inspection Institute, Xiamen, 361004 (China)

    2009-01-18

    Phytochelatins, with the general structure of ({gamma}-Glu-Cys)n-Gly (n = 2-11), are usually recognized as being strongly induced by metals in microalgae and play an important role in the detoxification of heavy metals in environment. However, there have been few studies on metallothionein (MT) synthesis in Chlorella vulgaris (C. vulgaris) exposed to heavy metals. The present study describes the growth inhibition of C. vulgaris exposed to different concentrations of cadmium and zinc, and the induction of metal-binding MT-like proteins in the cells. The amounts of metal-binding proteins, induced in the alga exposed to different concentrations of Cd and Zn, were analyzed with a size-exclusion HPLC coupled to ICP-MS. After being purified with a gel filtration column (Sephadex G-75, 3.5 cm x 80 cm) and a desalting column (G-25, 1.5 cm x 30 cm), the isoforms and sub-isoforms of Zn-binding protein were characterized by a reverse phase-HPLC coupled to electrospray ionization and a triple quadrupole mass spectrometer (HPLC-ESI-MS/MS). In addition, the ultraviolet spectra of purified Zn-binding proteins were analyzed in media with different pH values. The results showed that the significant inhibitory effects (at p < 0.05) on the cell growth were observed when excessive metals such as 80 {mu}mol l{sup -1} of Cd, and 60 and 80 {mu}mol l{sup -1} of Zn were added. The Cd/Zn-binding proteins induced in C. vulgaris exposed to Cd and Zn were referred to as Cd/Zn-MT-like proteins in which the mean molecular mass of the apo-MT-like was 6152 Da. The induced Cd/Zn-MT-like proteins might be involved in the detoxification of heavy metals, such as cadmium and zinc, by the alga.

  13. Effect of nutrient conditions on the toxicity of naphthalene to Chlorella pyrenoidosa

    Institute of Scientific and Technical Information of China (English)

    Qingxia Kong; Lizhong Zhu; Xueyou Shen

    2011-01-01

    The toxicity of naphthalene to a freshwater microalga, Chlorella pyrenoidosa, and the subsequent recovery of algae from the damage were investigated under two nutrient conditions, either enriched with nitrogen (N) and phosphorus (P), or starved of N and P.Results showed that C.pyrenoidosa was more sensitive to naphthalene under N,P-enriched condition, and the inhibitory rate generally increased at first and then decreased gradually with the evaporation of naphthalene under both nutrient conditions.Enriched N, P reduced the inhibitory rate at initial naphthalene concentration of 5 and 10 mg/L, but enhanced it at 100 mg/L, at which more severe ultrastucture damages were found than those under N,P-starved condition.Observed damages included partly or totally disappearance of nucleolus,nuclear, and plasma membranes.According to the chlorophyll content and cell density measurements, C.pyrenoidosa could recover from naphthalene damage with initial concentrations ≤ 50 mg/L in 7 days under both nutrient conditions, while they could not recover if the initial concentration of naphthalene was at 100 mg/L.Under the N,P-starved condition, the inability of C.pyrenoidosa to recover from the naphthalene damage was consistent with the results of high inhibitory rate, low value of specific growth rate (SGR, 0.05 day-1), and the severe destruction of cell structure.However, under the N,P-enriched conditions, the observed lower inhibitory rate,higher value of SGR (0.55 day-1), and the intact cell structure of most cells suggested that algae could potentially recover from the naphthalene damage.

  14. Long-term outdoor cultivation by perfusing spent medium for biodiesel production from Chlorella minutissima.

    Science.gov (United States)

    Oh, Sung Ho; Kwon, Min Chul; Choi, Woon Yong; Seo, Yong Chang; Kim, Ga Bin; Kang, Do Hyung; Lee, Shin Young; Lee, Hyeon Yong

    2010-08-01

    A unique perfusion process was developed to maintain high concentrations of marine alga, Chlorella minutissima. This method is based on recycling cells by continuous feeding with warm spent sea water from nuclear power plants, which has very similar properties as sea water. A temperature of at least 30 degrees C in a 200 L photo-bioreactor was maintained in this system by perfusion of the thermal plume for 80 days in the coldest season. The maximum cell concentration and total lipid content was 8.3 g-dry wt./L and 23.2 %, w/w, respectively, under mixotrophic conditions. Lipid production was found to be due to a partially or non-growth related process, which implies that large amounts of biomass are needed for a high accumulation of lipids within the cells. At perfusion rates greater than 1.5 L/h, the temperature of the medium inside the reactor was around 30 degrees C, which was optimal for cell growth. For this system, a perfusion rate of 2.8 L/h was determined to be optimal for maintaining rapid cell growth and lipid production during outdoor cultivation. It was absolutely necessary to maintain the appropriate perfusion rate so that the medium temperature was optimal for cell growth. In addition, the lipids produced using this process were shown to be feasible for biodiesel production since the lipid composition of C. minutissima grown under these conditions consisted of 17 % (w/w) of C(16) and 47% (w/w) of C(18). The combined results of this study clearly demonstrated that the discharged energy of the thermal plume could be reused to cultivate marine alga by maintaining a relatively constant temperature in an outdoor photo-bioreactor without the need for supplying any extra energy, which could allow for cheap production of biodiesel from waste energy.

  15. Spiruline, a virtuous algae

    OpenAIRE

    Various, Authors

    2015-01-01

    A short video about a local development practice focusing on the production and commercialization of spiruline, an algae used as an nutritional integrator. The practice was one of six prize winners resulting from a national competition for innovative practices of local development, launched by the Senegalese Ministry of local governance, development and territorial planning, with funding from the Italian Cooperation and technical support from the KIP International School.

  16. Nutrient utilization and oxygen production by Chlorella Vulgaris in a hybrid membrane bioreactor and algal membrane photobioreactor system

    KAUST Repository

    Najm, Yasmeen

    2017-02-17

    This work studied oxygen production and nutrient utilization by Chlorella Vulgaris at different organic/inorganic carbon (OC/IC) and ammonium/nitrate (NH4+-N/NO3--N) ratios to design a hybrid aerobic membrane bioreactor (MBR) and membrane photobioreactor (MPBR) system. Specific oxygen production by C. vulgaris was enough to support the MBR if high growth is accomplished. Nearly 100% removal (or utilization) of PO43--P and IC was achieved under all conditions tested. Optimal growth was achieved at mixotrophic carbon conditions (0.353 d-1) and the highest NH4+-N concentration (0.357 d-1), with preferable NH4+-N utilization rather than NO3--N. The results indicate the potential of alternative process designs to treat domestic wastewater by coupling the hybrid MBR - MPBR systems.

  17. 以市政污水为底物的微藻油脂积累和碳流分析%Microalgae lipid accumulation and carbon flux analysis based on municipal wastewater used as medium

    Institute of Scientific and Technical Information of China (English)

    李超; 冯玉杰; 张大伟; 初晓婉

    2012-01-01

    The commercial production of microalgae biodiesel was hindered by the higher cost of algae cultivation. In this study, municipal wastewater was used to cultivate Chlorella vulgaris under hydraulic retention time (HRT) 24 h, 48 h, 96 h and batch cultivation. The ratio of C.vulgaris in total biomass was enhanced along with the increase of HRT. Furthermore, cell density and lipid content also increased from 0.088 g/L and 8.4% under HRT 24 h to 0.164 g/L and 14.3% under batch cultivation, respectively. The treatment of wastewater was not influenced by HRT significantly. The removal efficiency of COD and TP was 66.1%~7I.1% and 37.6%~51.1%, respectively. However, TN removal efficiency was only 5.9%~11.2%. The carbon flux analysis of batch cultivation showed that 71.1% of organic carbon in wastewater was used by microalgae. Furthermore, 94.6% of used organic carbon was converted into algae biomass, and others into C02. The transfer ratio of wastewater organic carbon(COD) to microalgae lipid was 11.6 mg/(mg·L).%微藻培养的高成本阻碍了微藻生物柴油的工业化推广.文章以市政污水作为Chlorella vulgaris的培养基,分别在水力停留时间( HRT)24,48,96 h和间歇运行时对其进行培养.随着HRT的增加,C.vulgaris在系统生物群落中所占的比例增大,而且细胞密度和脂含量也分别由 HRT 24 h时的0.088g/L和8.4%提高到间歇时的0.164g/L和14.3%.HRT对废水处理效果的影响较小,不同 HRT时,COD和TP的去除率分别在66.1%~71.1%和37.6%~51.1%,TN的去除率则仅为5.9%~11.2%.对间歇污水处理过程碳元素流动分析表明,污水中的71.1%有机碳被微藻利用,其中 94.6%被转化为微藻生物质,其余被代谢为C02释放,废水中有机碳(COD)转化为微藻油脂的转化率为11.6 mg/( mg·L).

  18. Effects of magnetic field on the antioxidant defense system of recirculation-cultured Chlorella vulgaris.

    Science.gov (United States)

    Wang, Hai-Ying; Zeng, Xiao-Bo; Guo, Si-Yuan; Li, Zong-Tao

    2008-01-01

    Little is known about the influence of magnetic fields (MF) on growth of microalgae such as Chlorella vulgaris, which has been consumed as health food for various nutritional and pharmacological effects. This preliminary study investigated whether static MF can modulate the antioxidant system in C. vulgaris by exposing the cells to static MF generated by dual yoke electromagnets with magnetic flux density of 10-50 mT for 12 h. After exposure to 10-35 mT for 12 h, the activity of superoxide dismutases and peroxidase increased significantly compared to control cells. However, a remarkable increase of catalase activity occurred at 45 and 50 mT. The lipid peroxidation of algae cells determined by production of thiobarbituric acid-reactive substances was much increased when exposed to 35, 45, and 50 mT of MF. The scavenging ability of 2,2-diphenyl-1-picrylhydrazyl radical was decreased markedly while there was no variation of total carotenoids content in C. vulgaris cells. Assay of specific growth rate in 72 h cultivation after MF exposure was also conducted. In groups after exposure to 10-35 mT of MF, specific growth rate was significantly increased. These results suggest that 10-35 mT of static MF exposure could promote the growth of C. vulgaris and regulate its antioxidant defense system to protect cells efficiently, which could possibly enhance the growth of C. vulgaris in industrialized cultivation by MF.

  19. Effects of sodium pentaborate pentahydrate exposure on Chlorella vulgaris growth, chlorophyll content, and enzyme activities.

    Science.gov (United States)

    Chen, Xueqing; Pei, Yuansheng

    2016-10-01

    Sodium pentaborate pentahydrate (SPP) is a rare mineral. In this study, SPP was synthesized from boric acid and borax through low-temperature crystallization, and its effects on the growth of the alga, Chlorella vulgaris (C. vulgaris) were assessed. The newly synthesized SPP was characterized by chemical analysis, X-ray diffraction, Fourier-transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis, and differential thermal analysis. The changes in C. vulgaris growth, chlorophyll content, and enzyme activities upon exposure to SPP for 168h were evaluated. Results showed that SPP treatment was detrimental to C. vulgaris growth during the first 24-120h of exposure. The harmful effects, however, diminished over time (168h), even at an effective medium concentration of 226.37mg BL(-1) (the concentration of boron applied per liter of culture medium). A similar trend was observed for chlorophyll content (chlorophyll a and b) and indicated that the photosynthesis of C. vulgaris was not affected and that high levels of SPP may even promote chlorophyll synthesis. Superoxide dismutase and catalase activities of C. vulgaris increased during 24-120h exposure to SPP, but these activities gradually decreased as culture time progressed. In other words, the initial detrimental effects of synthetic SPP on C. vulgaris were temporary and reversible. This research provides a scientific basis for applications of SPP in the environment.

  20. Sorption Capacity Measurement of Chlorella Vulgaris and Scenedesmus Acutus to Remove Chromium from Tannery Waste Water

    Science.gov (United States)

    Ardila, Liliana; Godoy, Rubén; Montenegro, Luis

    2017-08-01

    Tanning process is a polluting activity due to the release of toxic agents into the environment. One of the most important of those toxic chemicals is chromium. Different alternatives have been proposed for the removal of this metal from tanning waste water which include the optimization of the productive processes, physicochemical and biochemical waste water treatment. In this study, the biological adsorption process of trivalent chromium was carried out in synthetic water and tannery waste water through two types of native green microalgae, called Chlorella vulgaris and Scenedesmus acutus in Free State and immobilized in PVA state. This, considering that cellular wall of microalgae has functional groups like amines and carboxyl that might bind with trivalent chromium. Statistical significance of variables as pH temperature, chromium and algae concentrations was evaluated just like bio sorption capacity of different types of water and kind of bioadsorbent was calculated to determine if this process is a competitive solution comparing to other heavy metal removal processes.

  1. Growth and biochemical composition of Chlorella vulgaris in different growth media

    Directory of Open Access Journals (Sweden)

    MATHIAS A. CHIA

    2013-10-01

    Full Text Available The need for clean and low-cost algae production demands for investigations on algal physiological response under different growth conditions. In this research, we investigated the growth, biomass production and biochemical composition of Chlorella vulgaris using semi-continuous cultures employing three growth media (LC Oligo, Chu 10 and WC media. The highest cell density was obtained in LC Oligo, while the lowest in Chu medium. Chlorophyll a, carbohydrate and protein concentrations and yield were highest in Chu and LC Oligo media. Lipid class analysis showed that hydrocarbons (HC, sterol esthers (SE, free fatty acids (FFA, aliphatic alcohols (ALC, acetone mobile polar lipids (AMPL and phospholipids (PL concentrations and yields were highest in the Chu medium. Triglyceride (TAG and sterol (ST concentrations were highest in the LC Oligo medium. The results suggested that for cost effective cultivation, LC Oligo medium is the best choice among those studied, as it saved the cost of buying vitamins and EDTA associated with the other growth media, while at the same time resulted in the best growth performance and biomass production.

  2. Lipid accumulation and growth of Chlorella zofingiensis in flat plate photobioreactors outdoors.

    Science.gov (United States)

    Feng, Pingzhong; Deng, Zhongyang; Hu, Zhengyu; Fan, Lu

    2011-11-01

    Culturing microalgae using natural sunlight is an effective way to reduce the cost of microalgae-based biodiesel production. In order to evaluate the feasibility of culturing Chlorella zofingiensis outdoors for biodiesel production, effects of nitrogen limitation and initial cell concentration on growth and lipid accumulation of this alga were investigated in 60 L flat plate photobioreactors outdoors. The highest μmax and biomass productivity obtained was 0.994 day(-1) and 58.4 mg L(-1)day(-1), respectively. The lipid content was much higher (54.5% of dry weight) under nitrogen limiting condition than under nitrogen sufficient condition (27.3%). With the increasing initial cell concentrations, the lipid contents declined, while lipid concentrations and productivities increased. The highest lipid content, lipid concentration, and lipid productivity obtained was 54.5%, 536 mg L(-1) and 22.3 mg L(-1)day(-1), respectively. This study demonstrated that it was possible to culture C. zofingiensis under outdoor conditions for producing biodiesel feedstock.

  3. Toxic effects of 1,4-dichlorobenzene on photosynthesis in Chlorella pyrenoidosa.

    Science.gov (United States)

    Zhang, Jinhua; Wang, Jie; Feng, Jia; Lv, Junping; Cai, Jin; Liu, Qi; Xie, Shulian

    2016-09-01

    1,4-Dichlorobenzene (1,4-DCB) is a common organic contaminant in water. To determine the effects of this contaminant on photosynthesis in the freshwater alga Chlorella pyrenoidosa, algal cells were treated with 1,4-DCB at different concentrations for various times, and their photosynthetic pigment contents and chlorophyll fluorescence traits were analyzed. The results showed that 1,4-DCB exerted toxic effects on photosynthesis in C. pyrenoidosa, especially at concentrations exceeding 10 mg/L. The inhibitory effects of 1,4-DCB were time- and concentration-dependent. After treatment with 1,4-DCB (≥10 mg/L), the contents of photosynthetic pigments decreased significantly, the photosystem II reaction center was irreversibly damaged, and the quantum yield of photosystem II decreased significantly. Also, there were sharp decreases in the efficiency of photosynthetic electron transport and energy conversion. Photosystem II became overloaded as the amount of excitation energy distributed to it increased. All of these events weakened the photochemical reaction, and ultimately led to serious inhibition of photosynthesis.

  4. Affinity Purification of O-Acetylserine(thiollyase from Chlorella sorokiniana by Recombinant Proteins from Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Giovanna Salbitani

    2014-08-01

    Full Text Available In the unicellular green alga Chlorella sorokiniana (211/8 k, the protein O-acetylserine(thiollyase (OASTL, representing the key-enzyme in the biosynthetic cysteine pathway, was isolated and purified to apparent homogeneity. The purification was carried out in cells grown in the presence of all nutrients or in sulphate (S deprived cells. After 24 h of S-starvation, a 17-fold increase in the specific activity of OASTL was measured. In order to enable the identification of OASTL proteins from non-model organisms such as C. sorokiniana, the recombinant his-tagged SAT5 protein from Arabidopsis thaliana was immobilized by metal chelate chromatography. OASTL proteins from C. sorokiniana were affinity purified in one step and activities were enhanced 29- and 41-fold, from S-sufficient and S-starved (24 h cells, respectively. The successful application of SAT/OASTL interaction for purification confirms for the first time the existence of the cysteine synthase complexes in microalgae. The purified proteins have apparent molecular masses between 32–34 kDa and are thus slightly larger compared to those found in Arabidopsis thaliana and other vascular plants. The enhanced OASTL activity in S-starved cells can be attributed to increased amounts of plastidic and the emergence of cytosolic OASTL isoforms. The results provide proof-of-concept for the biochemical analysis of the cysteine synthase complex in diverse microalgal species.

  5. Study of optimizing the process of Cadmium adsorption by synthesized silver nanoparticles using Chlorella vulgaris

    Directory of Open Access Journals (Sweden)

    Faezeh Sajadi

    2016-05-01

    Full Text Available Background and Aim: Cadmium (Cd is one of the most toxic heavy metals in water that mostly enters the water cycle through industrial waste water. Silver nanoparticles have the capacity to remove heavy metals from the water resources through the mechanism of adsorption. The present study aimed at producing  silver bio-nanoparticles and optimizing . Cd removal from aquatic solutions. Materials and Methods: Silver bio-nanoparticles were extracted via a micro-algae Chlorella vulgaris extract and silver nitrate synthesis. Then, the characteristics of the particles were  determined using FT-IR, XRD, SEM devices. In order to optimize Cadmium adsorption by means of silver nanoparticles, parameters including pH, reaction time, initial concentration of Cd and concentrations of nanoparticles were studied under different conditions. Results: The resulting nanoparticles were spherical, single and crystalline, whose sizes were 10-45 nm.  Under the condition of PH = 8, the initial concentration of cadmium 0.5 mg/L, adsorbent dosage of 0.5 mg, reaction time of 10 min, temperature of 300C and mixing speed of 200 rpm, 99% of cadmium was removed. Isotherm of Cadmium-ion adsorption followed Langmuir (R2> 0/96 (and Freundlich (R2> 0/94 models. Conclusion: Under optimal conditions, silver bio-nanoparticles had the capacity of quick and effective adsorption of cadmium. Thus, with a cheap, non-toxic and environmentally friendly method  can remove heavy metals in a short time.

  6. Effect of carbon source on growth and lipid accumulation in Chlorella sorokiniana GXNN01

    Institute of Scientific and Technical Information of China (English)

    QIAO Hongjin; WANG Guangce

    2009-01-01

    Heterotrophic culture of microalgae to develop methods of increasing biomass productivity and storage lipids has brought new insight to commercial biodiesel production. To understand the relationship between heterotrophy and lipid production, the effects of carbon sources on the growth and lipid accumulation of Chlorella sorokiniana GXNN01 was studied. The alga exhibited an increased growth rate in response to the addition of carbon sources, which reached the stationary phase after 48 h at 30°C. In addition, glucose and NaAc had a significant effect on the lipid accumulation during the early-stationary phase. Specifically, the lipid content was 0.237±0.026 g g~(-1) cell dry weight and 0.272±0.041 g L~(-1) when glucose was used as the carbon source, whereas the lipid content reached 0.287±0.018 g g~(-1) cell dry weight and 0.288±0.008 g L~(-1) when NaAc was used as the carbon source. The neutral lipid content was found to first decrease and then increase over time during the growth phase. A glucose concentration of 20 mmol L~(-1) gave the maximal lipid yield and the optimum harvest time was the early-stationary phase.

  7. Ecotoxicity of Ag-nanoparticles on two microalgae, Chlorella vulgaris and Dunaliella tertiolecta

    Directory of Open Access Journals (Sweden)

    Hazani Amal A.

    2013-01-01

    Full Text Available The increasing application of nanotechnology highlights the need to clarify and understand it. In this work, the subacute toxicity of Ag-NPs to the fresh water microalga Chlorella vulgaris and marine microalga Dunaliella tertiolecta were assessed. The effect of Ag-NPs was induced by exposing both algae to increasing concentrations of Ag-NPs (0, 10, 50, 100 and 200 mg/L. Cellular viability and reactive oxygen species (ROS formation were determined to evaluate the toxic effect of Ag-NPs on algal growth. Superoxide dismutase (SOD, catalase (CAT and peroxidase (POD activities and lipid peroxidation (MDA levels in the algal cells varied with the concentration of Ag-NPs suspensions and exposure times (up to 8 d. As a result, 100 and 200 mg/L Ag-NPs caused a statistically significant decrease in cell viability, as well as SOD, CAT and POD activities, and a significant increase in ROS formation and MDA levels in tissues (P <0.05, suggesting that the algal cells exposed to these two concentrations of Ag-NPs suffered from oxidative stress. The extent of depletion of antioxidant enzyme activities and the elevation of MDA in Dunaliella tertiolecta was the greatest, indicating that Dunaliella tertiolecta might be the most susceptible to Ag-NP exposure. These results indicated a potential risk from Ag-NPs released into the aqueous environment.

  8. Application of sweet sorghum for biodiesel production by heterotrophic microalga Chlorella protothecoides

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Chunfang; Zhai, Yan; Ding, Yi; Wu, Qingyu [School of Life Science, Tsinghua University, Beijing 100084 (China)

    2010-03-15

    Microalga Chlorella protothecoides can grow heterotrophically with glucose as the carbon source and accumulate high proportion of lipids. The microalgal lipids are suitable for biodiesel production. To further increase lipid yield and reduce biodiesel cost, sweet sorghum juice was investigated as an alternative carbon source to glucose in the present study. When the initial reducing sugar concentration was 10 g L{sup -1} in the culture medium, the dry cell yield and lipid content were 5.1 g L{sup -1} and 52.5% using enzymatic hydrolyzates of sweet sorghum juice as the carbon source after 120 h-culture in flasks. The lipid yield was 35.7% higher than that using glucose. When 3.0 g L{sup -1} yeast extract was added to the medium, the dry cell yield and lipid productivity was increased to 1.2 g L{sup -1} day{sup -1} and 586.8 mg L{sup -1} day{sup -1}. Biodiesel produced from the lipid of C. protothecoides through acid catalyzed transesterification was analyzed by GC-MS, and the three most abundant components were oleic acid methyl ester, cetane acid methyl ester and linoleic acid methyl ester. The results indicate that sweet sorghum juice could effectively enhance algal lipid production, and its application may reduce the cost of algae-based biodiesel. (author)

  9. Photorespiration participates in the assimilation of acetate in Chlorella sorokiniana under high light.

    Science.gov (United States)

    Xie, Xiujun; Huang, Aiyou; Gu, Wenhui; Zang, Zhengrong; Pan, Guanghua; Gao, Shan; He, Linwen; Zhang, Baoyu; Niu, Jianfeng; Lin, Apeng; Wang, Guangce

    2016-02-01

    The development of microalgae on an industrial scale largely depends on the economic feasibility of mass production. High light induces productive suspensions during cultivation in a tubular photobioreactor. Herein, we report that high light, which inhibited the growth of Chlorella sorokiniana under autotrophic conditions, enhanced the growth of this alga in the presence of acetate. We compared pigments, proteomics and the metabolic flux ratio in C. sorokiniana cultivated under high light (HL) and under low light (LL) in the presence of acetate. Our results showed that high light induced the synthesis of xanthophyll and suppressed the synthesis of chlorophylls. Acetate in the medium was exhausted much more rapidly in HL than in LL. The data obtained from LC-MS/MS indicated that high light enhanced photorespiration, the Calvin cycle and the glyoxylate cycle of mixotrophic C. sorokiniana. The results of metabolic flux ratio analysis showed that the majority of the assimilated carbon derived from supplemented acetate, and photorespiratory glyoxylate could enter the glyoxylate cycle. Based on these data, we conclude that photorespiration provides glyoxylate to speed up the glyoxylate cycle, and releases acetate-derived CO2 for the Calvin cycle. Thus, photorespiration connects the glyoxylate cycle and the Calvin cycle, and participates in the assimilation of supplemented acetate in C. sorokiniana under high light.

  10. Transcriptome profiling of the microalga Chlorella pyrenoidosa in response to different carbon dioxide concentrations.

    Science.gov (United States)

    Sun, Xue; Shen, Jia; Bai, Fengwei; Xu, Nianjun

    2016-10-01

    To enrich our knowledge of carbon dioxide (CO2)-concentrating mechanism (CCM) in eukaryotic algae, we used high-throughput sequencing to investigate the transcriptome profiling of the microalga Chlorella pyrenoidosa (Chlorophyta) response to different CO2 levels. Altogether, 53.86 million (M) and 62.10M clean short reads of 100 nucleotides (nt) were generated from this microalga cultured at 4-fold air CO2 (control) and air CO2 concentrations by Illumina sequencing. A total of 32,662 unigenes were assembled from the two pooled samples. With an E-value cut-off of 1e-5, 9590, 6782, 5954, and 9092 unigenes were annotated in NR, Gene Ontology (GO), Eukaryotic Cluster of Orthologous Groups of proteins (KOG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, respectively. After screening, 51 differentially expressed unigenes were up-regulated and 8 were down-regulated in the air CO2 group, relative to the control. The transcript levels of eight differentially expressed unigenes were validated by real-time quantitative PCR, which manifested that thioredoxin-like protein, laminin subunit beta-1, and chlorophyll a/b binding protein might be associated with the utilization of inorganic carbon at low CO2 levels.

  11. Toxicity of Nickel Oxide Nanoparticles on a Freshwater Green Algal Strain of Chlorella vulgaris

    Directory of Open Access Journals (Sweden)

    Abdallah Oukarroum

    2017-01-01

    Full Text Available A freshwater microalga strain of Chlorella vulgaris was used to investigate toxic effects induced by nickel oxide nanoparticles (NiO-NPs in suspension. Algal cells were exposed during 96 h to 0–100 mg L−1 of NiO-NPs and analyzed by flow cytometry. Physicochemical characterization of nanoparticles in tested media showed a soluble fraction (free Ni2+ of only 6.42% for 100 mg L−1 of NiO-NPs, indicating the low solubility capacity of these NPs. Toxicity analysis showed cellular alterations which were related to NiO-NPs concentration, such as inhibition in cell division (relative cell size and granularity, deterioration of the photosynthetic apparatus (chlorophyll synthesis and photochemical reactions of photosynthesis, and oxidative stress (ROS production. The change in cellular viability demonstrated to be a very sensitive biomarker of NiO-NPs toxicity with EC50 of 13.7 mg L−1. Analysis by TEM and X-ray confirmed that NiO-NPs were able to cross biological membranes and to accumulate inside algal cells. Therefore, this study provides a characterization of both physicochemical and toxicological properties of NiO-NPs suspensions in tested media. The use of the freshwater strain of C. vulgaris demonstrated to be a sensitive bioindicator of NiO-NPs toxicity on the viability of green algae.

  12. Oxidative stress and antioxidant content in Chlorella vulgaris after exposure to ultraviolet-B radiation

    Energy Technology Data Exchange (ETDEWEB)

    Malanga, G.; Puntarulo, S. [Univ. of Buenos Aires, Physical Chemistry, School of Pharmacy and Biochemistry, Buenos Aires (Argentina)

    1995-08-01

    Growth of Chlorella vulgaris was measured in cultures irradiated with 0, 0.8, 2.0 and 4.4 kJ m{sup -2} UV-B. Growth expressed as chlorophyll content, declined significantly with increased UV-B dose. Ultraviolet-B irradiated cultures in log phase of growth showed a 284% increase in oxygen radical generation and a 145% increase in lipid peroxidation compared with unirradiated cultures, whereas cultures in the stationary growth phase showed no significant changes in these parameters. The activities of superoxide dismutase and catalase increased by 40 and 500%, respectively, after exposure to a UV-B dose of 4.4 kJ m{sup -2}. Contents of the lipophilic antioxidants {alpha}-tocopherol and {beta}-carotene increased by 180 and 63 amol cell{sup -1} respectively, between log and stationary phases in unirradiated cultures: but in UV-B-irradiated cultures these increases were significantly depressed. Photoreducing capacities of chloroplasts were decreased following UV-B irradiation of both isolated chloroplasts and those isolated from irradiated algae. Cells exposed to UV-B exhibited increased size and starch accumulation. These results suggest that oxidative stress conditions related to UV-B exposure trigger and antioxidant response that includes an increase in the activity of the antioxidant enzymes (superoxide dismutase and catalase). (au) 40 refs.

  13. Producción artesanal del rotífero Philodina sp. y de algas para la alimentación de post-larvas de bocachico Artisan production of rotifero and algaes for bocachico post-larva feeding

    Directory of Open Access Journals (Sweden)

    Victoria Eugenia Quintero P

    2009-01-01

    Full Text Available El cultivo de algas mixtas se realizó en el Instituto de Piscicultura Tropical de la Corporación Autónoma Regional del Valle del Cauca (Buga 25 ºC y 969 m.s.n.m. utilizando fertilizantes inorgánicos en baldes plásticos, se produjeron en promedio 386 x 10³ células/ml de cultivo. En el cultivo de Philodina en frascos de vidrio alimentado con algas y levadura, se obtuvieron 410 rotíferos/ml de cultivo. Se evaluaron tres tratamientos: rotíferos enriquecidos con aceite de pescado; rotíferos más algas (Chlorella, Scenedesmus, Pediastrum, Spyrogira y Anabaena y Artemia salina + Spirulina, usando 100 post-larvas de bocachico/acuario, alimentadas dos veces al día según biomasa sembrada. El mayor porcentaje de sobrevivencia, peso y talla se obtuvo con el alimento constituido por rotíferos enriquecidos con aceite de pescado (93 %,3.2mg, 6.86mm, seguido de rotíferos + algas (80.67 %,2 mg, 6.1mm y Artemia+ Spirulina (60.6 %,1.6mg, 6.06mm respectivamenteIn the Tropical Piscicultural Institute of the Regional Autonomous Corporation of Buga, Cauca, Valley, Colombia (25ºC temperature, 969 m a s l, a research was carried out with the objective to produce and use algaes and rotifers (living food cultures to feed bocachico post-larvas (Prochilodus reticulatus magdalenae. A complete random design with three treatments and three repetitions was established. 100 bocachico/aquarium post larva were used and fed twice a day according to sown biomass. The cultures of mixed algaes were established by using inorganic fertilizers produced in plastic pails and obtaining an average of 386 x 10³ cells/ml of culture. On the other hand, the cultures of Philodina rotifers were established in glass bottles and feeding them with algaes and yeast. An average of 410 rotifers/ml of culturing was obtained . To evaluate the highest rate of survival, growing and weight of bocachico post-larvas, three kind of food were used: Rotifers enriched with fish oil; rotifers plus

  14. Nitrogen and phosphorus removing from wastewater by six species of algal biofilm%六种藻类膜脱氮除磷的实验研究

    Institute of Scientific and Technical Information of China (English)

    蔡元妃; 魏群; 郭莉娜; 孙红云; 周军; 张金莲

    2013-01-01

    The removal effects of nitrogen and phosphorus from wastewater were investigated with six species of algal biofilm ( Oedogonium sp.,Anabaena flos-aquae,Chlorella pyrenoidosa,Scenedesmus obliqnus,Hydrodictyon reticulatum,Oscillatoria agardhii) under continuous light of 3 500 lx,temper-ature of (25 ±2)℃and PVC as the carrier.The volume of waste water was 1 800 mL ,and regarded NaNO3 , ( NH4 ) 2 SO4 , KH2 PO4 as nitrogen and phosphorus nutrition , the initial concentration of to-tal phosphorus (TP),total nitrogen (TN),ammonia nitrogen (NH4+-N) reached 10.57,36.56, 19.40 mg/L, respectively .The results showed that Chlorella pyrenoidosa was most suited to form al-gae biofilm ,and the removal efficiencies of TP , TN ,NH4+-N reached 87.88%,87.27%,89.25%, respectively .There were no positive correlation between removal efficiencies of nitrogen and phos-phorus and chlorphyll content of biofilm , chlorphyll content of Chlorella pyrenoidosa was lowest , reaching 0.065 4 mg/L, and Anabaena flos-aquae was highest ,reaching 0.245 0 mg/L.%  在连续光照强度为3500 lx,温度为(25±2)℃的实验条件下,以硝酸钠、硫酸铵、磷酸二氢钾为氮磷营养源,配制1800 mL模拟废水,其总磷( TP)、总氮( TN)、氨氮( NH4+-N)的初始浓度分别为10.57、36.56、19.40 mg/L,以立体弹性聚氯乙烯为载体,鞘藻( Oedogonium sp.)、水华鱼腥藻( Anabaena flos-aquae)、蛋白核小球藻( Chlorella pyrenoidosa)、斜生栅藻( Scenedesmus obliquus)、水网藻( Hydrodictyon reticulatum)、阿氏颤藻( Oscillatoria agardhii)等为实验藻种,进行了为期6 d的藻类膜脱氮除磷实验。结果表明:在6种实验藻种中,蛋白核小球藻最适合作为脱氮除磷废水处理的挂膜藻种,其藻类膜的TP、TN、NH4+-N去除率最高,分别为87.88%、87.27%、89.25%;藻类膜脱氮除磷能力与其叶绿素含量无正相关性,蛋白核小球藻藻类膜的

  15. Assessing the energy and environmental performance of algae-mediated tertiary treatment of estrogenic compounds.

    Science.gov (United States)

    Colosi, Lisa M; Resurreccion, Eleazer P; Zhang, Yongli

    2015-02-01

    This study uses a systems-level modeling approach to illustrate a novel synergy between municipal wastewater treatment and large-scale algaculture for production of bio-energy, whereby algae-mediated tertiary treatment provides efficient removal of unregulated, strongly estrogenic steroid hormones from the secondary effluent. Laboratory results from previously published studies suggested that algae-mediated treatment could deliver roughly 75-85% removal of a model estrogen (17β-estradiol) within typical algae pond residence times. As such, experimental results are integrated into a comprehensive life cycle assessment (LCA) framework, to assess the environmental performance of an algae-based tertiary treatment system relative to three conventional tertiary treatments: ozonation, UV irradiation, and adsorption onto granular activated carbon. Results indicate that the algae-mediated tertiary treatment is superior to the selected benchmarks on the basis of raw energy return on investment (EROI) and normalized energy use per mass of estrogenic toxicity removed. It is the only tertiary treatment system that creates more energy than it consumes, and it delivers acceptable effluent quality for nutrient and coliform concentrations while rendering a significant reduction in estrogenic toxicity. These results highlight the dual water and energy sustainability benefits that accrue from the integration of municipal wastewater treatment and large-scale algae farming.

  16. The potential of sustainable algal biofuel production using wastewater resources.

    Science.gov (United States)

    Pittman, Jon K; Dean, Andrew P; Osundeko, Olumayowa

    2011-01-01

    The potential of microalgae as a source of renewable energy has received considerable interest, but if microalgal biofuel production is to be economically viable and sustainable, further optimization of mass culture conditions are needed. Wastewaters derived from municipal, agricultural and industrial activities potentially provide cost-effective and sustainable means of algal growth for biofuels. In addition, there is also potential for combining wastewater treatment by algae, such as nutrient removal, with biofuel production. Here we will review the current research on this topic and discuss the potential benefits and limitations of using wastewaters as resources for cost-effective microalgal biofuel production. Copyright © 2010 Elsevier Ltd. All rights reserved.

  17. The effect of natural organic matter on bioaccumulation and toxicity of chlorobenzenes to green algae.

    Science.gov (United States)

    Zhang, Shuai; Lin, Daohui; Wu, Fengchang

    2016-07-05

    The effect of natural organic matter (NOM) on toxicity and bioavailability of hydrophobic organic contaminants (HOCs) to aquatic organisms has been investigated with conflicting results and undefined mechanisms, and few studies have been conducted on volatile HOCs. In this study, six volatile chlorobenzenes (CBs) with 1-6 chlorine substitutions were investigated for their bioaccumulation in an acute toxicity to a green alga (Chlorella pyrenoidosa) in the presence/absence of Suwannee River NOM (SRNOM). The fluorescence quenching efficiency of SRNOM increased as the number of chlorine substitutions of CBs increased. SRNOM increased the cell-surface hydrophobicity of algae and decreased the release rates of algae-accumulated CBs, thus increasing the concentration factor (CF) and accumulation of the CBs in the algae. SRNOM increased the toxicity of monochlorobenzene and 1,2-dichlorobenzene, decreased the toxicity of pentachlorobenzene and hexachlorobenzene, and had no significant effect on the toxicity of 1,2,3-trichlorobenzene and 1,2,3,4-tetrachlorobenzene. Relationships between the 96 h CF/IC50 (i.e., the CB concentration leading to a 50% algal growth reduction compared with the control) and physicochemical properties of CBs with/without SRNOM were established, providing reasonable explanations for the experimental results. These findings will help with the accurate assessment of ecological risks of organic pollutants in the presence of NOM.

  18. Enhancement of carotenoid and chlorophyll content of an edible freshwater alga (Kai: Cladophora sp. by supplementary inorganic phosphate and investigation of its biomass production

    Directory of Open Access Journals (Sweden)

    Siripen Traichaiyaporn

    2012-01-01

    Full Text Available Enhancement of the carotenoid and chlorophyll content of an edible freshwater alga (Kai:Cladophora sp. by supplementary inorganic phosphate in canteen wastewater was investigated. Themass cultivation of the alga was conducted at ambient temperature and light intensity in dilutedcanteen wastewater enhanced with dipotassium hydrogen phosphate at 5-20 mg L-1. An increase intotal carotenoid and chlorophyll was observed. However, it had no effect on biomass production. Asa result of the algal cultivation, there was a dramatic improvement in the quality of canteen wastewater.

  19. Screening and characterization of oleaginous Chlorella strains and exploration of photoautotrophic Chlorella protothecoides for oil production.

    Science.gov (United States)

    Sun, Zheng; Zhou, Zhi-gang; Gerken, Henri; Chen, Feng; Liu, Jin

    2015-05-01

    The growth and oil production of nine Chlorella strains were comparatively assessed and Chlorellaprotothecoides CS-41 demonstrated the greatest lipid production potential. The effects of different nitrogen forms and concentrations, phosphorus concentrations and light intensities on growth and oil production were studied in laboratory columns. C. protothecoides CS-41 accumulated lipids up to 55% of dry weight, with triacylglycerol and oleic acid being 71% of total lipids and 59% of total fatty acids, respectively. High biomass and lipid productivities were achieved in outdoor panel PBRs, up to 1.25 and 0.59 g L(-1) day(-1), or 44. 1 and 16.1 g m(-2) day(-1), respectively. A two-stage cultivation strategy was proposed to enhance the algal biomass and lipid production. This is the first comprehensive investigation of both indoor and outdoor photoautotrophic C. protothecoides cultures for oil production, and C. protothecoides CS-41 represents a promising biofuel feedstock worthy of further exploration.

  20. The OMEGA system for marine bioenergy, wastewater treatment, environmental enhancement, and aquaculture

    Science.gov (United States)

    Trent, J. D.

    2013-12-01

    OMEGA is an acronym for Offshore Membrane Enclosure for Growing Algae. The OMEGA system consists of photobioreactors (PBRs) made of flexible, inexpensive clear plastic tubes attached to floating docks, anchored offshore in naturally or artificially protected bays [1]. The system uses domestic wastewater and CO2 from coastal facilities to provide water, nutrients, and carbon for algae cultivation [2]. The surrounding seawater maintains the temperature inside the PBRs and prevents the cultivated (freshwater) algae from becoming invasive species in the marine environment (i.e., if a PBR module accidentally leaks, the freshwater algae that grow in wastewater cannot survive in the marine environment). The salt gradient between seawater and wastewater is used for forward osmosis (FO) to concentrate nutrients and facilitate algae harvesting [3]. Both the algae and FO clean the wastewater, removing nutrients as well as pharmaceuticals and personal-care products [4]. The offshore infrastructure provides a large surface area for solar-photovoltaic arrays and access to offshore wind or wave generators. The infrastructure can also support shellfish, finfish, or seaweed aquaculture. The economics of the OMEGA system are supported by a combination of biofuels production, wastewater treatment, alternative energy generation, and aquaculture. By using wastewater and operating offshore from coastal cities, OMEGA can be located close to wastewater and CO2 sources and it can avoid competing with agriculture for water, fertilizer, and land [5]. By combining biofuels production with wastewater treatment and aquaculture, the OMEGA system provides both products and services, which increase its economic feasibility. While the offshore location has engineering challenges and concerns about the impact and control of biofouling [6], large OMEGA structure will be floating marine habitats and will create protected 'no-fishing' zones that could increase local biodiversity and fishery

  1. Chlorella protects against hydrogen peroxide-induced pancreatic β-cell damage.

    Science.gov (United States)

    Lin, Chia-Yu; Huang, Pei-Jane; Chao, Che-Yi

    2014-12-01

    Oxidative stress has been implicated in the etiology of pancreatic β-cell dysfunction and diabetes. Studies have shown that chlorella could be important in health promotion or disease prevention through its antioxidant capacity. However, whether chlorella has a cytoprotective effect in pancreatic β-cells remains to be elucidated. We investigated the protective effects of chlorella on H2O2-induced oxidative damage in INS-1 (832/13) cells. Chlorella partially restored cell viability after H2O2 toxicity. To further investigate the effects of chlorella on mitochondria function and cellular oxidative stress, we analyzed mitochondria membrane potential, ATP concentrations, and cellular levels of reactive oxygen species (ROS). Chlorella prevented mitochondria disruption and maintained cellular ATP levels after H2O2 toxicity. It also normalized intracellular levels of ROS to that of control in the presence of H2O2. Chlorella protected cells from apoptosis as indicated by less p-Histone and caspase 3 activation. In addition, chlorella not only enhanced glucose-stimulated insulin secretion (GSIS), but also partially restored the reduced GSIS after H2O2 toxicity. Our results suggest that chlorella is effective in amelioration of cellular oxidative stress and destruction, and therefore protects INS-1 (832/13) cells from H2O2-induced apoptosis and increases insulin secretion. Chlorella should be studied for use in the prevention or treatment of diabetes.

  2. Vitreoscilla hemoglobin gene ( vgb) improves lutein production in Chlorella vulgaris

    Science.gov (United States)

    Ma, Ruijuan; Lin, Xiangzhi

    2014-03-01

    Vitreoscilla hemoglobin is an oxygen-binding protein that promotes oxygen delivery and reduces oxygen consumption under low oxygen conditions to increase the efficiency of cell respiration and metabolism. In this study, we introduced a Vitreoscilla hemoglobin gene ( vgb) into Chlorella vulgaris by Agrobacterium tumefaciens -mediated transformation (ATMT). PCR analysis confirmed that the vgb gene was successfully integrated into the Chlorella vulgaris genome. Analysis of biomass obtained in shake flasks revealed transformant biomass concentrations as high as 3.28 g/L, which was 38.81% higher than that of the wild-type strain. Lutein content of transformants also increased slightly. Further experiments recovered a maximum lutein yield of 2.91 mg/L from the transformants, which was 36.77% higher than that of the wild-type strain. The above results suggest that integrated expression of the vgb gene may improve cell growth and lutein yield in Chlorella vulgaris, with applications to lutein production from Chlorella during fermentation.

  3. Chlorella vulgaris: A Multifunctional Dietary Supplement with Diverse Medicinal Properties.

    Science.gov (United States)

    Panahi, Yunes; Darvishi, Behrad; Jowzi, Narges; Beiraghdar, Fatemeh; Sahebkar, Amirhossein

    2016-01-01

    Chlorella vulgaris is a green unicellular microalgae with biological and pharmacological properties important for human health. C. vulgaris has a long history of use as a food source and contains a unique and diverse composition of functional macro- and micro-nutrients including proteinsChlorella vulgaris is a green unicellular microalgae with biological and pharmacological properties important for human health. C. vulgaris has a long history of use as a food source and contains a unique and diverse composition of functional macro- and micro-nutrients including proteins, omega-3 polyunsaturated fatty acids, polysaccharides, vitamins and minerals. Clinical trials have suggested that supplementation with C. vulgaris can ameliorate amelioration hyperlipidemia and hyperglycemia, and protect against oxidative stress, cancer and chronic obstructive pulmonary disease. In this review, we summarize the findings on the health benefits of Chlorella supplementation and the molecular mechanisms underlying these effects., omega-3 polyunsaturated fatty acids, polysaccharides, vitamins and minerals. Clinical trials have suggested that supplementation with C. vulgaris can ameliorate amelioration hyperlipidemia and hyperglycemia, and protect against oxidative stress, cancer and chronic obstructive pulmonary disease. In this review, we summarize the findings on the health benefits of Chlorella supplementation and the molecular mechanisms underlying these effects.