WorldWideScience

Sample records for caproates

  1. Conversion of L-lactate into n-caproate by a continuously fed reactor microbiome.

    Science.gov (United States)

    Kucek, Leo A; Nguyen, Mytien; Angenent, Largus T

    2016-04-15

    Conversion of lactate to n-caproate had been described for the type strain Megasphaera elsdenii in batch systems. Recently, investigators have also described production of n-caproate from endogenous or exogenous lactate with batch-fed reactor microbiome systems. However, no reports exist of lactate to n-caproate conversion within a continuously fed bioreactor. Since continuously fed systems are advantageous for biotechnology production platforms, our objective was to develop such a system. Here, we demonstrated continuous lactate to n-caproate conversion for more than 165 days. The volumetric n-caproate production rate (productivity) was improved when we decreased the operating pH from 5.5 to 5.0, and was again improved when we utilized in-line product recovery via pertraction (membrane-based liquid-liquid extraction). We observed a maximum n-caproate productivity of 6.9 g COD/L-d for a period of 17 days at an L-lactate loading rate of 9.1 g COD/L-d, representing the highest sustained lactate to n-caproate conversion rate ever reported. We had to manage two competing lactate conversion pathways: 1) the reverse β-oxidation pathway to n-caproate; and 2) the acrylate pathway to propionate. We found that maintaining a low residual lactate concentration in the bioreactor broth was necessary to direct lactate conversion towards n-caproate instead of propionate. These findings provide a foundation for the development of new resource recovery processes to produce higher-value liquid products (e.g., n-caproate) from carbon-rich wastewaters containing lactate or lactate precursors (e.g., carbohydrates).

  2. Relationship between 17-hydroxyprogesterone caproate concentrations and gestational age at delivery in twin gestation.

    LENUS (Irish Health Repository)

    Caritis, Steve N

    2012-11-01

    We sought to evaluate in women with twin gestation the relationship between 17-hydroxyprogesterone caproate (17-OHPC) concentration and gestational age at delivery and select biomarkers of potential pathways of drug action.

  3. Biological formation of caproate and caprylate from acetate: fuel and chemical production from low grade biomass

    NARCIS (Netherlands)

    Steinbusch, K.J.J.; Hamelers, H.V.M.; Plugge, C.M.; Buisman, C.J.N.

    2011-01-01

    This research introduces an alternative mixed culture fermentation technology for anaerobic digestion to recover valuable products from low grade biomass. In this mixed culture fermentation, organic waste streams are converted to caproate and caprylate as precursors for biodiesel or chemicals. It wa

  4. Second trimester cervical length and risk of preterm birth in women with twin gestations treated with 17-α hydroxyprogesterone caproate.

    LENUS (Irish Health Repository)

    Durnwald, Celeste P

    2010-12-01

    To compare rates of preterm birth before 35 weeks based on cervical length measurement at 16-20 weeks in women with twin gestations who received 17-α hydroxyprogesterone caproate (17OHPC) or placebo.

  5. 17-alpha-hydroxyprogesterone caproate for maintenance tocolysis: a systematic review and metaanalysis of randomized trials.

    Science.gov (United States)

    Saccone, Gabriele; Suhag, Anju; Berghella, Vincenzo

    2015-07-01

    We sought to evaluate the efficacy of maintenance tocolysis with 17-alpha-hydroxyprogesterone caproate (17P) compared to control (either placebo or no treatment) in singleton gestations with arrested preterm labor (PTL), in a metaanalysis of randomized trials. Electronic databases (MEDLINE, OVID, Scopus, ClinicalTrials.gov, and the Cochrane Central Register of Controlled Trials) were searched from 1966 through July 2014. Key words included "progesterone," "tocolysis," "preterm labor," and "17-alpha-hydroxyprogesterone caproate." We performed a metaanalysis of randomized trials of singleton gestations with arrested PTL and treated with maintenance tocolysis with either 17P or control. Primary outcome was preterm birth (PTB) metaanalysis was performed following the Preferred Reporting Items for Systematic Reviews and Metaanalyses (PRISMA) statement. The protocol was registered with PROSPERO (registration no: CRD42014013473). Five randomized trials met inclusion criteria, including 426 women. Women with a singleton gestation who received 17P maintenance tocolysis for arrested PTL had a similar rate of PTB metaanalysis of the available randomized trials. As 17P for maintenance tocolysis is associated with a significant prolongation of pregnancy, and significantly higher birthweight, further research is suggested.

  6. Metabolism of 17alpha-hydroxyprogesterone caproate by hepatic and placental microsomes of human and baboons.

    Science.gov (United States)

    Yan, Ru; Nanovskaya, Tatiana N; Zharikova, Olga L; Mattison, Donald R; Hankins, Gary D V; Ahmed, Mahmoud S

    2008-05-01

    Recent data from our laboratory revealed the formation of an unknown metabolite of 17 hydroxyprogesterone caproate (17-HPC), used for treatment of preterm deliveries, during its perfusion across the dually perfused human placental lobule. Previously, we demonstrated that the drug is not hydrolyzed, neither in vivo nor in vitro, to progesterone and caproate. Therefore, the hypothesis for this investigation is that 17-HPC is actively metabolized by human and baboon (Papio cynocephalus) hepatic and placental microsomes. Baboon hepatic and placental microsomes were investigated to validate the nonhuman primate as an animal model for drug use during pregnancy. Data presented here indicate that human and baboon hepatic microsomes formed several mono-, di-, and tri-hydroxylated derivatives of 17-HPC. However, microsomes of human and baboon placentas metabolized 17-HPC to its mono-hydroxylated derivatives only in quantities that were a fraction of those formed by their respective livers, except for two metabolites (M16' and M17') that are unique for placenta and contributed to 25% and 75% of the total metabolites formed by human and baboon, respectively. The amounts of metabolites formed, relative to each other, by human and baboon microsomes were different suggesting that the affinity of 17-HPC to CYP enzymes and their activity could be species-dependent.

  7. Studies on the thermal decomposition of lanthanum(III) valerate and lanthanum(III) caproate in argon

    DEFF Research Database (Denmark)

    Grivel, Jean-Claude; Yue, Zhao; Suarez Guevara, Maria Josefina;

    2015-01-01

    The decomposition of La-valerate (La(C4H9CO2)3·xH2O (x ≈ 0.45)) and La-caproate (La(C5H11CO2)3·xH2O (x ≈ 0.30)) was studied upon heating at 5 C/min in a flow of argon. Using a variety of techniques including simultaneous TG-DTA, FTIR, X-ray diffraction with both laboratory Cu Kα and synchrotron s...

  8. Studies on the thermal decomposition of lanthanum(III) valerate and lanthanum(III) caproate in argon

    Energy Technology Data Exchange (ETDEWEB)

    Grivel, J.-C., E-mail: jean@dtu.dk [Department of Energy Conversion and Storage, Technical University of Denmark, Frederiksborgvej 399, DK - 4000 Roskilde (Denmark); Zhao, Y.; Suarez Guevara, M.J. [Department of Energy Conversion and Storage, Technical University of Denmark, Frederiksborgvej 399, DK - 4000 Roskilde (Denmark); Watenphul, A. [Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22603 Hamburg (Germany); Institute of Mineralogy and Petrography, University of Hamburg, Grindelallee 48, 20146 Hamburg (Germany)

    2015-07-20

    Highlights: • The thermal decomposition of Lathanum valerate and caproate has been studied in Ar. • The compounds melt prior to decomposition. • Gas release in the molten state results in irregular mass loss. • CO{sub 2} and symmetrical ketones are the main evolving gas species. - Abstract: The decomposition of La-valerate (La(C{sub 4}H{sub 9}CO{sub 2}){sub 3}·xH{sub 2}O (x ≈ 0.45)) and La-caproate (La(C{sub 5}H{sub 11}CO{sub 2}){sub 3}·xH{sub 2}O (x ≈ 0.30)) was studied upon heating at 5 °C/min in a flow of argon. Using a variety of techniques including simultaneous TG-DTA, FTIR, X-ray diffraction with both laboratory Cu Kα and synchrotron sources as well as hot-stage microscopy, it was found that both compounds melt prior to decomposition and that the main decomposition stage from the molten, anhydrous state leads to the formation of La-dioxycarbonate (La{sub 2}O{sub 2}CO{sub 3}) via an unstable intermediate product and release of symmetrical ketones. Final decomposition to La{sub 2}O{sub 3} takes place with release of CO{sub 2}.

  9. Production of butyrate and caproate from a coculture of Sporomusa ovata and Clostridium kluyveri during MES

    DEFF Research Database (Denmark)

    Ammam, Fariza; Tremblay, Pier-Luc; Faraghi Parapari, Neda;

    2014-01-01

    the lack of genetic tools. S. ovata is able to produceethanol and acetate while C. kluyveri uses these two compounds as carbon source and producesbutyrate and caproate.The first step was to optimize the growth medium for S. ovata to increase ethanol production. Theeffect of trace metal ions such as SeO4...

  10. Comparison of Risk of Preterm Labor between Vaginal Progesterone and17-Alpha-Hydroxy-Progesterone Caproate in Women with Threatened Abortion: A Randomized Clinical Trial

    Directory of Open Access Journals (Sweden)

    Beigi Abootaleb

    2016-07-01

    Full Text Available Objective Threatened miscarriage is a common complication in pregnancy that leads to adverse pregnancy outcomes such as preterm labor. This study aimed to compare the vaginal progesterone (Cyclogest versus 17-alpha-hydroxyprogesterone caproate (Proluton on preventing preterm labor in pregnant women with threatened abortion at less than 34 weeks’ gestational age. Materials and methods This balanced randomized, double-blind, single-center controlled clinical trial included 190 women with threatened abortion. They were then randomly allocated into Cyclogest (n=95 and 17-alpha-hydroxyprogesterone caproate (Proluton, n=95 groups. Interested outcome was preterm labor less than 34 weeks. The Pearson chi-square and Student’s t test were used to compare two groups. The data were analyzed by Stata software version 13. Results The risks of preterm labor less than 34 weeks in Proluton and Cyclogest groups were 8.6 and 6.52%, respectively. There was no significant difference for risk of preterm labor less than 34 weeks [relative ratio (RR: 1.31, 95% confidence interval (CI: 0.47- 3.66, P=0.59] between two groups. Conclusion Risk of preterm labor in the vaginal progesterone group and 17-alpha-hydroxyprogesterone caproate group in pregnant women with threatened abortion is the same (Registration Number: IRCT2014123120504N1.

  11. Critical appraisal of the efficacy, safety, and patient acceptability of hydroxyprogesterone caproate injection to reduce the risk of preterm birth

    Directory of Open Access Journals (Sweden)

    Vidaeff AC

    2013-07-01

    Full Text Available Alex C Vidaeff, Michael A BelfortDivision of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital, Houston, TX, USAAbstract: Prevention of preterm delivery is a major desiderate in contemporary obstetrics and a societal necessity. The means to achieve this goal remain elusive. Progesterone has been used in an attempt to prevent preterm delivery since the 1970s, but the evidence initially accumulated was fraught by mixed results and was based on mostly underpowered studies with variable eligibility criteria, including history of spontaneous abortion as an indication for treatment. More recent randomized controlled clinical trials restimulated the interest in progesterone supplementation, suggesting that progesterone may favorably influence the rate of preterm delivery. Preterm delivery is a complex disorder and consequently it is unlikely that one generalized prevention strategy will be effective in all patients. Further, an additional impediment in accepting progesterone as the "magic bullet" in the prevention of preterm delivery is that its mechanism of action is not fully understood and the optimal formulations, route of administration, and dose have yet to be established. We have concerned ourselves in this review with the most recent status of 17 alpha-hydroxyprogesterone caproate (17OH-PC supplementation for prevention of preterm delivery. Our intention is to emphasize the efficacy, safety, and patient acceptability of this intervention, based on a comprehensive and unbiased review of the available literature. Currently there are insufficient data to suggest that 17OH-PC is superior or inferior to natural progesterone. Based on available evidence, we suggest a differential approach giving preferential consideration to either 17OH-PC or other progestins based on obstetric history and cervical surveillance. Progestin therapy for risk factors other than a history of preterm

  12. 新型Lewis酸铁钾矾催化合成己酸乙酯%Catalytic Synthesis of Ethyl Caproate over New Lewis Acid Ferric Potassium Alum

    Institute of Scientific and Technical Information of China (English)

    郭小丹; 张福捐

    2012-01-01

    新型Lewis酸铁钾矾催化己酸和乙醇合成反应生成己酸乙酯,其性能优于硫酸,并且是一种绿色催化剂.研究了催化剂的用量、酸醇摩尔比、反应时间对酯化反应的影响.实验结果表明,较佳的反应条件为:催化剂用量1.0 g/0.05 mol己酸,酸醇物质的量比为1∶2.4,反应时间为100 min,此条件下己酸转化率为94.3%.%Ethyl caproate was synthesized from hexanoic acid and ethyl alcohol with new Lewis acid ferric potassium alum as catalyst.The factors of influencing esterification rate were investigated.The results showed that ferric potassium alum was a good green catalyst for synthesis of ethyl caproate.The optimum conditions were:molar ratio of hexanoic acid to ethyl alcohol was 1∶ 2.4,amount of catalyst was 1.0 g /0.05 mol hexanoic acid,the water-carrying toluene was 10 mL,and the reaction time was 100 min.The highest esterification rate was 94.3%,and the catalyst can be recycled for many times.

  13. Waste conversion into n-caprylate and n-caproate: resource recovery from wine lees using anaerobic reactor microbiomes and in-line extraction

    Directory of Open Access Journals (Sweden)

    Leo A. Kucek

    2016-11-01

    Full Text Available To convert wastes into sustainable liquid fuels and chemicals, new resource recovery technologies are required. Chain elongation is a carboxylate-platform bioprocess that converts short-chain carboxylates (SCCs (e.g., acetate C2 and n-butyrate C4 into medium-chain carboxylates (MCCs (e.g., n-caprylate C8 and n-caproate C6 with hydrogen gas as a side product. Ethanol or another electron donor (e.g., lactate, carbohydrate is required. Competitive MCC productivities, yields (product vs. substrate fed, and specificities (product vs. all products were only achieved previously from an organic waste material when exogenous ethanol had been added. Here, we converted a real organic waste, which inherently comprised of ethanol, into MCCs with n-caprylate as the target product. We used wine lees, which consisted primarily of settled yeast cells and ethanol from wine fermentation, and produced MCCs with a reactor microbiome. We operated the bioreactor at a pH of 5.2 and with continuous in-line extraction and achieved a MCC productivity of 3.9 g COD/L-d at an organic loading rate of 5.8 g COD/L-d, resulting in a promising MCC yield of 67% and specificities of 36% for each n-caprylate and n-caproate (72% for both. Compared to all other studies that used complex organic substrates, we achieved the highest n-caprylate-to-n-caproate product ratio of 1.0 (COD basis, because we used increased broth-recycle rates through the forward membrane contactor, which improved in-line extraction rates. Increased recycle rates also allowed us to achieve the highest reported MCC production flux per membrane surface area thus far (20.1 g COD/m2-d. Through microbial community analyses, we determined that an operational taxonomic unit (OTU for Bacteroides spp. was dominant and was positively correlated with increased MCC productivities. Our data also suggested that the microbiome may have been shaped for improved MCC production by the high broth-recycle rates. Comparable abiotic

  14. 17-Hydroxyprogesterone caproate to prolong pregnancy after preterm rupture of the membranes: early termination of a double-blind, randomized clinical trial

    Directory of Open Access Journals (Sweden)

    Combs C Andrew

    2011-12-01

    Full Text Available Abstract Background Progestational agents may reduce the risk of preterm birth in women with various risk factors. We sought to test the hypothesis that a weekly dose of 17-hydroxyprogesterone caproate (17P given to women with preterm rupture of the membranes (PROM will prolong pregnancy and thereby reduce neonatal morbidity. Methods Double-blind, placebo-controlled randomized clinical trial. Women with PROM at 23.0 to 31.9 weeks of gestation were randomly assigned to receive a weekly intramuscular injection of 17P (250 mg in 1 mL castor oil or placebo (1 mL castor oil. The primary outcome was the rate of continuing the pregnancy until 34.0 weeks of gestation or until documentation of fetal lung maturity at 32.0 to 33.9 weeks of gestation. Planned secondary outcomes were duration of latency period and rate of composite neonatal morbidity. Enrollment of 111 participants per group, 222 total, was planned to yield 80% power to detect an increase in the primary outcome from 30% with placebo to 50% with 17P. Results Twelve women were enrolled of whom 4 were randomly assigned to receive 17P and 8 to receive placebo. The trial was terminated prematurely because of two separate issues related to the supply of 17P. No adverse events attributable to 17P were identified. Conclusion Because of premature termination, the trial does not have adequate statistical power to evaluate efficacy or safety of 17P in women with PROM. Nonetheless, ethical principles dictate that we report the results, which may contribute to possible future metaanalyses and systematic reviews. Trial Registration ClinicalTrials.gov: NCT01119963 Supported by a research grant from the Center for Research, Education, and Quality, Pediatrix Medical Group, Sunrise, FL

  15. Development and validation of a high-performance liquid chromatography-mass spectrometric assay for the determination of 17alpha-hydroxyprogesterone caproate (17-OHPC) in human plasma.

    Science.gov (United States)

    Zhang, Shimin; Mada, Sripal Reddy; Mattison, Don; Caritis, Steve; Venkataramanan, Raman

    2007-09-01

    A sensitive and specific method for the determination of 17alpha-hydroxyprogesterone caproate (17-OHPC) in human plasma using high-performance liquid chromatography and mass spectrometry has been developed and validated. Plasma samples were processed by a solid phase extraction (SPE) procedure using Oasis HLB extraction cartridge prior to chromatography. Medroxyprogesterone acetate (MPA) was used as the internal standard. Chromatography was performed using Waters C18 Symmetry analytical column, 3.5 microm, 2.1 mm x 10 mm, using a gradient elusion with a mobile phase consisting of acetonitrile [A] and 5% acetonitrile in water [B], with 0.1% formic acid being added to both [A] and [B], at a flow rate 0.2 ml/min. The retention times of 17-OHPC and MPA were 8.1 and 5.0 min, respectively, with a total run time of 15 min. Analysis was performed on Thermo Electron Finnigan TSQ Quantum Ultra mass spectrometer in a selected reaction-monitoring (SRM), positive mode using electron spray ionization (ESI) as an interface. Positive ions were measured using extracted ion chromatogram mode. The extracted ions following SRM transitions monitored were m/z 429.2-->313.13 and 429.2-->271.1, for 17-OHPC and m/z 385.1-->276 for MPA. The extraction recoveries at concentrations of 5, 10 and 50 ng/ml were 97.1, 92.6 and 88.7%, respectively. The assay was linear over the range 0.5-50 ng/ml for 17-OHPC. The analysis of standard samples for 17-OHPC 0.5, 1, 2.5, 5, 10, 25 and 50 ng/ml demonstrated a relative standard deviation of 16.7, 12.4, 13.7, 1.4, 5.2, 3.7 and 5.3%, respectively (n=6). This method is simple, adaptable to routine application, and allows easy and accurate measurement of 17-OHPC in human plasma.

  16. Methanol as an alternative electron donor in chain elongation for butyrate and caproate formation

    NARCIS (Netherlands)

    Chen, W.S.; Ye, Y.; Steinbusch, K.J.J.; Strik, D.P.B.T.B.; Buisman, C.J.N.

    2016-01-01

    Chain elongation is an emerging mixed culture biotechnology converting acetate into valuable biochemicals by using ethanol as an external electron donor. In this study we proposed to test another potential electron donor, methanol, in chain elongation. Methanol can be produced through the thermoc

  17. 75 FR 36419 - Determination That DELALUTIN (hydroxyprogesterone caproate) Injection, 125 Milligrams/Milliliter...

    Science.gov (United States)

    2010-06-25

    ... several years had indicated that the use of sex hormones during early pregnancy may seriously damage the... uterine cancer; as a presumptive test for pregnancy; as a test for continuous endogenous progesterone... teratogenic effects is considered high enough to warrant removal of pregnancy-related indications from...

  18. Drug: D04457 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available estrogens, fixed combinations G03FA02 Hydroxyprogesterone and estrogen D04457 Hydroxyprogesterone caproate - estradiol dipropionate mixt PubChem: 17398112 ... ...ITAL SYSTEM G03F PROGESTOGENS AND ESTROGENS IN COMBINATION G03FA Progestogens and

  19. Development of a mixed culture chain elongation process based on municipal solid waste and ethanol

    NARCIS (Netherlands)

    Grootscholten, T.I.M.

    2013-01-01

    Keywords: mixed culture fermentation; Carboxylates; Caproate; Heptanoate; ethanol; OFMSW To reduce dependence on oil, alternative fuel and chemical production processes are investigates. In this thesis, we investigated the production of medium chain fatty acids (MCFAs) using an anaerobic chain elon

  20. 酸掺杂聚苯胺催化2-(二乙氨基)乙基己酸酯及反应动力学%Synthesis and Kinetics of 2-(Diethylamino) Ethyl Caproate by Polyaniline Doped with p-Toluene Sulfonic Acid as Catalyst

    Institute of Scientific and Technical Information of China (English)

    刘艳杰; 丁斌; 郝凤岭; 关昶

    2015-01-01

    以正己酸和二乙氨基乙醇为原料,对甲苯磺酸掺杂聚苯胺为催化剂催化合成2-(二乙氨基)乙基己酸酯,考察反应过程的影响因素,并测定反应动力学数据.表明适宜的合成工艺条件为n(二乙氨基乙醇)∶n(正己酸)为1∶2,催化剂用量为醇酸总质量的2%,带水剂用量为醇酸总质量的120%,反应时间为3.2h.此时,二乙氨基乙醇转化率可达96.8%,催化剂重复使用4次后,二乙氨基乙醇的转化率为84.4%.采用还原后的催化剂进行的实验二乙氨基乙醇转化率可达95.2%.表观活化能为74.256 kJ/mol,指前因子为2.70×107 L/ (mol·min).对甲苯磺酸掺杂聚苯胺具有很好的催化活性.该酯化反应对正己酸和二乙氨基乙醇均为一级反应.

  1. Drug: D09796 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D09796 Drug Hydrocortisone caproate (JAN) C27H40O6 460.2825 460.6029 D09796.gif Sam... STOMATOLOGICAL PREPARATIONS A01AC Corticosteroids for local oral treatment A01AC03 Hydrocortisone D09796 Hydrocortison...NFECTIVE AGENTS A07E INTESTINAL ANTIINFLAMMATORY AGENTS A07EA Corticosteroids acting locally A07EA02 Hydrocortisone D09796 Hydrocorti...ATMENT OF HEMORRHOIDS AND ANAL FISSURES FOR TOPICAL USE C05AA Corticosteroids C05AA01 Hydrocortison...e D09796 Hydrocortisone caproate (JAN) D DERMATOLOGICALS D07 CORTICOSTEROIDS, DERMATOLOGIC

  2. Drug: D01159 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available tic category of drugs in Japan [BR:br08301] 2 Agents affecting individual organs 24 Hormones 247 Estrogen an...G03DA01] D01159 Gestonorone caproate (JAN/USAN) Antineoplastics [BR:br08308] Hormones and hormone antagonist

  3. ARO in Review 2012

    Science.gov (United States)

    2012-01-01

    Disease Control and Prevention (CDC) TOTAL: DHHS 1 1 TOTAL FY12 SSP Tasks 77 PROGRAM DESCRIPTIONS...capabilities. B. Increasing Conversion Efficiency of Biomass into n-caproate with Reactor Microbiomes Professor Largus Angenent, Cornell University, Single...is anticipated that in FY13, the research team will determine whether changes in the hydrogen partial pressures will alter the microbiome composition

  4. Chain Elongation with Reactor Microbiomes: Open-Culture Biotechnology To Produce Biochemicals

    NARCIS (Netherlands)

    Angenent, L.T.; Richter, H.; Buckel, W.; Spirito, C.M.; Steinbusch, K.J.J.; Plugge, C.M.; Strik, D.; Grootscholten, T.I.M.; Buisman, C.J.N.; Hamelers, H.V.M.

    2016-01-01

    Chain elongation into medium-chain carboxylates, such as n-caproate and n-caprylate, with ethanol as an electron donor and with open cultures of microbial consortia (i.e., reactor microbiomes) under anaerobic conditions is being developed as a biotechnological production platform. The goal is to use

  5. Effect of hydrogen and carbon dioxide on carboxylic acids patterns in mixed culture fermentation

    NARCIS (Netherlands)

    Arslan, D.; Steinbusch, K.J.J.; Diels, L.; Wever, De H.; Buisman, C.J.N.; Hamelers, H.V.M.

    2012-01-01

    This study investigated the carboxylate spectrum from mixed culture fermentation of three organic waste streams after supplying 2 bar hydrogen and carbon dioxide or a mixture of these two gases to the headspace. Under any modified headspace, propionate production was ceased and butyrate, caproate an

  6. In-line and selective phase separation of medium-chain carboxylic acids using membrane electrolysis.

    Science.gov (United States)

    Xu, Jiajie; Guzman, Juan J L; Andersen, Stephen J; Rabaey, Korneel; Angenent, Largus T

    2015-04-21

    We had extracted n-caproate from bioreactor broth. Here, we introduced in-line membrane electrolysis that utilized a pH gradient between two chambers to transfer the product into undissociated n-caproic acid without chemical addition. Due to the low maximum solubility of this acid, selective phase separation occurred, allowing simple product separation into an oily liquid containing ∼90% n-caproic and n-caprylic acid.

  7. Fatty acids production from hydrogen and carbon dioxide by mixed culture in the membrane biofilm reactor.

    Science.gov (United States)

    Zhang, Fang; Ding, Jing; Zhang, Yan; Chen, Man; Ding, Zhao-Wei; van Loosdrecht, Mark C M; Zeng, Raymond J

    2013-10-15

    Gasification of waste to syngas (H2/CO2) is seen as a promising route to a circular economy. Biological conversion of the gaseous compounds into a liquid fuel or chemical, preferably medium chain fatty acids (caproate and caprylate) is an attractive concept. This study for the first time demonstrated in-situ production of medium chain fatty acids from H2 and CO2 in a hollow-fiber membrane biofilm reactor by mixed microbial culture. The hydrogen was for 100% utilized within the biofilms attached on the outer surface of the hollow-fiber membrane. The obtained concentrations of acetate, butyrate, caproate and caprylate were 7.4, 1.8, 0.98 and 0.42 g/L, respectively. The biomass specific production rate of caproate (31.4 mmol-C/(L day g-biomass)) was similar to literature reports for suspended cell cultures while for caprylate the rate (19.1 mmol-C/(L day g-biomass)) was more than 6 times higher. Microbial community analysis showed the biofilms were dominated by Clostridium spp., such as Clostridium ljungdahlii and Clostridium kluyveri. This study demonstrates a potential technology for syngas fermentation in the hollow-fiber membrane biofilm reactors.

  8. Progestogens and Pregnancy

    Directory of Open Access Journals (Sweden)

    Schindler AE

    2015-01-01

    Full Text Available Based upon the intensive research by E. Diczfalusy and his scholars with the concept of the “feto-placental-unit”, the development of diagnostic procedures by hormone measurements in pregnancy, therapeutic and preventive effects of the use of progestogens (progesterone, dydrogesterone, 17-alpha-hydroxyprogesterone caproate were developed and are at present to be further evaluated in order to be used for prevention and treatment of pregnancy disorders such as threatened miscarriage, recurrent (habitual miscarriage, preterm labor and preeclampsia (hypertension in pregnancy.

  9. Progesterone for the prevention of preterm birth: indications, when to initiate, efficacy and safety

    Directory of Open Access Journals (Sweden)

    Helen Y How

    2008-12-01

    Full Text Available Helen Y How, Baha M SibaiDivision of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, University of Cincinnati, Cincinnati, OH USAAbstract: Preterm birth is the leading cause of neonatal mortality and morbidity and long-term disability of non-anomalous infants. Previous studies have identified a prior early spontaneous preterm birth as the risk factor with the highest predictive value for recurrence. Two recent double blind randomized placebo controlled trials reported lower preterm birth rate with the use of either intramuscular 17 alpha-hydroxyprogesterone caproate (IM 17OHP-C or intravaginal micronized progesterone suppositories in women at risk for preterm delivery. However, it is still unclear which high-risk women would truly benefit from this treatment in a general clinical setting and whether socio-cultural, racial and genetic differences play a role in patient’s response to supplemental progesterone. In addition the patient’s acceptance of such recommendation is also in question. More research is still required on identification of at risk group, the optimal gestational age at initiation, mode of administration, dose of progesterone and long-term safety.Keywords: preterm birth prevention, 17-alpha-hydroxyprogesterone caproate

  10. Caatinga plants: Natural and semi-synthetic compounds potentially active against Trichomonas vaginalis.

    Science.gov (United States)

    Vieira, Patrícia de Brum; Silva, Nícolas Luiz Feijó; da Silva, Gloria Narjara Santos; Silva, Denise Brentan; Lopes, Norberto Peporine; Gnoatto, Simone Cristina Baggio; da Silva, Márcia Vanusa; Macedo, Alexandre José; Bastida, Jaume; Tasca, Tiana

    2016-05-01

    Trichomonas vaginalis causes trichomoniasis; the most common but overlooked non-viral sexually transmitted disease worldwide. The treatment is based at 5'-nitroimidazoles, however, failure are related to resistance of T. vaginalis to chemotherapy. Caatinga is a uniquely Brazilian region representing a biome with type desert vegetation and plants present diverse biological activity, however, with few studies. The aim of this study was to investigate the activity against T. vaginalis of different plants from Caatinga and identify the compounds responsible by the activity. A bioguided fractionation of Manilkara rufula was performed and four major compounds were identified: caproate of α-amyrin (1b), acetate of β-amyrin (2a), caproate of β-amyrin (2b), and acetate of lupeol (3a). In addition, six derivatives of α-amyrin (1), β-amyrin (2) and lupeol (3) were synthesized and tested against the parasite. Ursolic acid (5) reduced about 98% of parasite viability after 2h of incubation and drastic ultrastructural alterations were observed by scanning electron microscopy. Moreover, 5 presented high cytotoxicity to HMVII and HeLa cell line and low cytotoxicity against Vero line at 50 μM (MIC against the parasite). Metronidazole effect against T. vaginalis resistant isolate was improved when in association with 5.

  11. Infrared, thermal and X-ray diffraction analysis of cerium soaps

    Energy Technology Data Exchange (ETDEWEB)

    Mehrotra, K.N. [Agra Univ. (India). Dept. of Chemistry; Chauhan, M. [Agra Univ. (India). Dept. of Chemistry; Shukla, R.K. [R.B.S. Coll., Agra (India)

    1997-03-01

    The physico-chemical characteristics of cerium soaps (Caproate and caprate) in solid state were investigated by IR, thermal and X-ray diffraction measurements. The IR results reveal that the fatty acids exist in dimeric state through hydrogen bonding and soaps possess partial ionic character. The decomposition reaction was found kinetically of zero order with energy of activation 6.7 and 7.3 K cal mol{sup -1} for cerium caproate and caprate, respectively. The X-ray diffraction measurements were used to calculate the long spacings and the results confirm the double layer structure of cerium soaps. (orig.) [Deutsch] Mit Hilfe von IR-, thermischen und Roentgendiffraktionsmessungen wurden die physikalisch-chemischen Eigenschaften von Cerseifen (Capron- und Caprylsaeuresalze)in festem Zustand bestimmt. Die IR-Untersuchungen zeigen, dass die Fettseifen in dimerem Zustand, gebunden durch Wasserstoffbruecken vorliegen und partiell ionischen Charakter haben. Die Zersetzungsreaktion war von einer Kinetik nullter Ordnung, die Aktivierungsenergien lagen bei 6,7 K cal mol{sup -1} fuer Capronsaeuresalze und 7,3 K cal mol{sup -1} fuer Caprylsaeuresalze. Mit Hilfe von Roentgendiffraktionsmessungen wurden die grossen Zwischenraeume bestimmt. Die Ergebnisse lassen auf eine Doppelschichtstruktur der Cerseifen schliessen. (orig.)

  12. Redirection of Metabolic Hydrogen by Inhibiting Methanogenesis in the Rumen Simulation Technique (RUSITEC)

    Science.gov (United States)

    Guyader, Jessie; Ungerfeld, Emilio M.; Beauchemin, Karen A.

    2017-01-01

    A decrease in methanogenesis is expected to improve ruminant performance by allocating rumen metabolic hydrogen ([2H]) to more energy-rendering fermentation pathways for the animal. However, decreases in methane (CH4) emissions of up to 30% are not always linked with greater performance. Therefore, the aim of this study was to understand the fate of [2H] when CH4 production in the rumen is inhibited by known methanogenesis inhibitors (nitrate, NIT; 3-nitrooxypropanol, NOP; anthraquinone, AQ) in comparison with a control treatment (CON) with the Rumen Simulation Technique (RUSITEC). Measurements started after 1 week adaptation. Substrate disappearance was not modified by methanogenesis inhibitors. Nitrate mostly seemed to decrease [2H] availability by acting as an electron acceptor competing with methanogenesis. As a consequence, NIT decreased CH4 production (−75%), dissolved dihydrogen (H2) concentration (−30%) and the percentages of reduced volatile fatty acids (butyrate, isobutyrate, valerate, isovalerate, caproate and heptanoate) except propionate, but increased acetate molar percentage, ethanol concentration and the efficiency of microbial nitrogen synthesis (+14%) without affecting gaseous H2. Nitrooxypropanol decreased methanogenesis (−75%) while increasing both gaseous and dissolved H2 concentrations (+81% and +24%, respectively). Moreover, NOP decreased acetate and isovalerate molar percentages and increased butyrate, valerate, caproate and heptanoate molar percentages as well as n-propanol and ammonium concentrations. Methanogenesis inhibition with AQ (−26%) was associated with higher gaseous H2 production (+70%) but lower dissolved H2 concentration (−76%), evidencing a lack of relationship between the two H2 forms. Anthraquinone increased ammonium concentration, caproate and heptanoate molar percentages but decreased acetate and isobutyrate molar percentages, total microbial nitrogen production and efficiency of microbial protein synthesis (

  13. Metabolic effects of feeding high doses of propanol and propylacetate to lactating Holstein cows

    DEFF Research Database (Denmark)

    Raun, Birgitte Marie Løvendahl; Kristensen, Niels Bastian

    2012-01-01

    BHBA and acetate concentrations; increased net portal flux of propanol; increased net hepatic flux of glucose; and increased propanol, isopropanol, and caproate uptake by the liver. Contrary to our hypothesis that propylacetate supplementation would exacerbate the metabolic effects of propanol, we...... observed for a number of variables that treatment differences between C and P were partly reversed in PPA. This applied to ruminal propanol and propylacetate; arterial concentrations of ethanol, propanol, isopropanol, and isobutyrate; net portal flux of ethanol, propanol, and isopropanol; net hepatic flux...... of BHBA, propanol, isopropanol, and isobutyrate; net splanchnic flux of propionate; hepatic extraction of ethanol and portal recovery of dietary ethanol. The overall metabolic effect of feeding large doses of propanol was a glucogenic response presumably driven by hepatic metabolism of propanol...

  14. Preparation of tamarind gum based soft ion gels having thixotropic properties.

    Science.gov (United States)

    Sharma, Mukesh; Mondal, Dibyendu; Mukesh, Chandrakant; Prasad, Kamalesh

    2014-02-15

    Tamarind gum was used to prepare ion gels using both synthetic ionic liquids (ILs) namely 1-butyl-3-methylimidazolium chloride and 1-butyl-3-methylimidazolium bromide and bio-based ionic liquids (Bio-ILs) namely choline acrylate, choline caproate and choline caprylate by heating cooling process. The gels were found to have good thermal stability and exhibited thixotropic behaviour. Upon relaxation after applied breaking strain, the recovery of gel structures after ten consecutive cycles was observed. The hydrogel of the gum prepared using ethanol aqueous solution had much inferior quality in terms of viscosity, viscoelasticity, thermal stability and thixotropicity when compared with the ion gels. The ion gels also showed very good adherence to human finger muscles and skin. The ion gels thus prepared may find application in electrochemistry, sensors, actuators and the gels prepared with Bio-ILs could even be useful in biomedical applications.

  15. Alcohol-to-acid ratio and substrate concentration affect product structure in chain elongation reactions initiated by unacclimatized inoculum.

    Science.gov (United States)

    Liu, Yuhao; Lü, Fan; Shao, Liming; He, Pinjing

    2016-10-01

    The objective of the study was to investigate whether the ratio of ethanol to acetate affects yield and product structure in chain elongation initiated by unacclimatized mixed cultures. The effect of varying the substrate concentration, while maintaining the same ratio of alcohol to acid, was also investigated. With a high substrate concentration, an alcohol to acid ratio >2:1 provided sufficient electron donor capacity for the chain elongation reaction. With an ethanol to acetate ratio of 3:1 (300mM total carbon), the highest n-caproate concentration (3033±98mg/L) was achieved during the stable phase of the reaction. A lower substrate concentration (150mM total carbon) gave a lower yield of products and led to reduced carbon transformation efficiency compared with other reaction conditions. The use of unacclimatized inoculum in chain elongation can produce significant amounts of odd-carbon-number carboxylates as a result of protein hydrolysis.

  16. Effect of hydrogen and carbon dioxide on carboxylic acids patterns in mixed culture fermentation.

    Science.gov (United States)

    Arslan, D; Steinbusch, K J J; Diels, L; De Wever, H; Buisman, C J N; Hamelers, H V M

    2012-08-01

    This study investigated the carboxylate spectrum from mixed culture fermentation of three organic waste streams after supplying 2 bar hydrogen and carbon dioxide or a mixture of these two gases to the headspace. Under any modified headspace, propionate production was ceased and butyrate, caproate and the total carboxylate concentrations were higher than in the reactors with N(2) headspace (control). Production of one major compound was achieved under hydrogen and carbon dioxide mixed headspace after 4 weeks of incubation. Both the highest acetate concentration (17.4 g COD/l) and the highest fraction (87%) were observed in reactors with mixed hydrogen and carbon dioxide headspace independent of the substrate used. In the control reactor, acetate made up maximum 67% of the total products. For other products, the highest concentration and fraction were seldom observed together. Selective butyrate production reaching a 75% fraction was found under the carbon dioxide headspace on the carbohydrate rich waste.

  17. Comparison of fermentation of diets of variable composition and microbial populations in the rumen of sheep and Rusitec fermenters. I. Digestibility, fermentation parameters, and microbial growth.

    Science.gov (United States)

    Martínez, M E; Ranilla, M J; Tejido, M L; Ramos, S; Carro, M D

    2010-08-01

    Four ruminally and duodenally cannulated sheep and 8 Rusitec fermenters were used to determine the effects of forage to concentrate (F:C) ratio and type of forage in the diet on ruminal fermentation and microbial protein synthesis. The purpose of the study was to assess how closely fermenters can mimic the dietary differences found in vivo. The 4 experimental diets contained F:C ratios of 70:30 or 30:70 with either alfalfa hay or grass hay as the forage. Microbial growth was determined in both systems using (15)N as a microbial marker. Rusitec fermenters detected differences between diets similar to those observed in sheep by changing F:C ratio on pH; neutral detergent fiber digestibility; total volatile fatty acid concentrations; molar proportions of acetate, propionate, butyrate, isovalerate, and caproate; and amylase activity. In contrast, Rusitec fermenters did not reproduce the dietary differences found in sheep for NH(3)-N and lactate concentrations, dry matter (DM) digestibility, proportions of isobutyrate and valerate, carboxymethylcellulase and xylanase activities, and microbial growth and its efficiency. Regarding the effect of the type of forage in the diet, Rusitec fermenters detected differences between diets similar to those found in sheep for most determined parameters, with the exception of pH, DM digestibility, butyrate proportion, and carboxymethylcellulase activity. Minimum pH and maximal volatile fatty acid concentrations were reached at 2h and at 6 to 8h postfeeding in sheep and fermenters, respectively, indicating that feed fermentation was slower in fermenters compared with that in sheep. There were differences between systems in the magnitude of most determined parameters. In general, fermenters showed lower lactate concentrations, neutral detergent fiber digestibility, acetate:propionate ratios, and enzymatic activities. On the contrary, fermenters showed greater NH(3)-N concentrations, DM digestibility, and proportions of propionate

  18. Hunter color dimensions, sugar content and volatile compounds in pasteurized yellow passion fruit juice (Passiflora edulis var. flavicarpa during storage

    Directory of Open Access Journals (Sweden)

    Delcio Sandi

    2004-06-01

    Full Text Available Changes in Hunter L, a and b values, glucose, fructose and sucrose contents, concentration of four volatile compounds (ethyl butirate, ethyl caproate, hexyl butirate and hexyl caproate and furfural, were studied in yellow passion fruit juice (Passiflora edulis var. flavicarpa pasteurized at 75ºC/60s, 80ºC/41s or 85ºC/27s, during storage at room temperature (25±5ºC and refrigeration (5±1ºC for 120 days. While the sucrose content decreased, the glucose and fructose contents increased significantly over storage time. The Hunter L and b values behaved similarly, with a tendency to decrease over time, inversely to Hunter a value. Volatile compound concentrations also decreased over time, inversely to the furfural content. Pasteurization at 85ºC/27s resulted minimum changes in the studied passion fruit characteristics, while that at 75ºC/60s was the most harmful. Storage under refrigeration tended to keep the best quality characteristics of the juice.Foi estudada a variação dos valores "L", "a" e "b" do sistema de Hunter, dos teores de glucose, frutose e sacarose, e da concentração de quatro compostos voláteis (butirato de etila, caproato de etila, butirato de hexila e caproato de hexila e furfural, em suco de maracujá-amarelo (Passiflora edulis var. flavicarpa submetido à pasteurização (75ºC/60 s, 80ºC/41 s e 85ºC/27 s, durante o armazenamento a temperatura ambiente (25±5ºC e refrigerada (5±1ºC por 120 dias. Enquanto os teores de sacarose diminuíram, aqueles de glucose e frutose aumentaram significativamente. Os valores "L" e "b" apresentaram comportamento semelhante, com tendência a diminuir ao longo do tempo, inversamente ao valor "a". As concentrações dos compostos voláteis também diminuíram, exceto para o furfural. A pasteurização a 85ºC/27 s proporcionou as menores alterações nas características estudadas, enquanto aquela à 75ºC/60 s foi a mais prejudicial. O armazenamento sob refrigeração apresentou

  19. Molecular phylogenetical studies of the thermophilic spore-forming desulfotomaculum isolated from oil-field

    Institute of Scientific and Technical Information of China (English)

    Chen Wu; Li Chunyan; Xiang Fu; Yu Longjiang

    2005-01-01

    A novel thermophilic and heterotrophic sulfate-reducing bacteria, strain CW-03, was isolated from crude oil well whose depth was 3.2 kilometer. The bacterium was strictly anaerobic; it does not endure acid and itsmaximum surviving temperature was 70℃. Many short chain organic compounds can be utilized as electron donors, which were acetate, formate, lactate, propionate, pyruvate, butyrate, succinate, malate, fumarate,valerate, caproate, heptanoate, octanoate, decanoate, tridecanoate, pentadecanoate, palmitate, heptadecanoate or ethanol, while sulfate and sulfite were used as electron acceptors. The following substrates were not utilized: benzoate undecanoate, dodecanoate, tetradecane, propanol, butanol, H2+CO2 (80/20%; v/v) and acetate (1mM)+ H2. When lactate was used as electron donors, sulfite and thiosulfate, but not sulfer and nitrate, can be used as electron acceptors. Strain CW-03 was motile, curved rod, Gram-positive, pole flagellum and spore-forming. On the basis of 16S rRNA sequence alignment (accession numbers: AY703032), CW-03 should be included in the genus Desulfotomaculum with BIAST analysis on line. However, some of its physiology and multiple sequence alignments were different from other members of this genus. Therefore, CW-03 should be recognized as a new species, for which we propose the name Desulfotomaculum chinamiddle (Bacteria, Firmicutes, Clostridia, Clostridiales, Peptococcaceae).

  20. Characterization of EstB, a novel cold-active and organic solvent-tolerant esterase from marine microorganism Alcanivorax dieselolei B-5(T).

    Science.gov (United States)

    Zhang, Shanshan; Wu, Guojie; Liu, Zhixiang; Shao, Zongze; Liu, Ziduo

    2014-03-01

    A novel esterase gene, estB, was cloned from the marine microorganism Alcanivorax dieselolei B-5(T) and overexpressed in E. coli DE3 (BL21). The expressed protein EstB with a predicted molecular weight of 45.1 kDa had a distinct catalytic triad (Ser(211)-Trp(353)-Gln(385)) and the classical consensus motif conserved in most lipases and esterases Gly(209)-X-Ser(211)-X-Gly(213). EstB showed very low similarity to any known proteins and displayed the highest similarity to the hypothetical protein (46%) from Rhodococcus jostii RHA1. EstB showed the optimal activity around pH 8.5 and 20 °C and was identified to be extremely cold-adaptative retaining more than 95% activity between 0 and 10 °C. The values of kinetic parameters on p-NP caproate (K m, K cat and K cat/K m) were 0.15 mM, 0.54 × 10(3) s(-1) and 3.6 × 10(3) s(-1) mM(-1), respectively. In addition, EstB showed remarkable stability in several studied organic solvents and detergents of high concentrations with the retention of more than 70% activity after treatment for 30 min. The cold activity and its tolerance towards organic solvents made it a promising biocatalyst for industrial applications under extreme conditions.

  1. Effects of Fatty Acid Salts against Trichophyton Violaceum

    Directory of Open Access Journals (Sweden)

    Era Mariko

    2016-01-01

    Full Text Available Trichophyton violaceum is an anthropophilic fungus. Dermatophytosis (Tinea is fungal infection that can infect the scalp, glabrous skin, and nails. In general, Tinea can be spread by skin-to-skin contact or bathroom or floor materials. The treatments of Tinea need antifungal medication and good hygiene environment. The effective antifungal medication and infection prevention, and the creation of antifungal medication with high safety are required. In this study was focused on the antifungal effect of fatty acids potassium salts. The antifungal activity of nine fatty acid salts (butyrate, caproate, caprylate, caprate, laurate, myristate, oleate, linoleate, and linolenate was tested on the spores of Trichophyton violaceum NBRC 31064. The results show that C6K, C8K, C10K, C12K, C18:2K, C18:3K was the most inhibit 4-log unit (99.99 % of the fatty acids potassium incubated time for 10 min. It was observed that C12K and C18:3K was most high antifungal activity MIC. Commercially soap was lowest antifungal activity. This is because of the oleic acid is a major component of soap. Although further investigation is necessary to make clear antifungal mechanisms, our results suggest that fatty acid potassium will use to the development of a coating agent such as furniture.

  2. Physical Properties, Volatiles Compositions and Sensory Descriptions of the Aromatized Hazelnut Oil-Wax Organogels.

    Science.gov (United States)

    Yılmaz, Emin; Öğütcü, Mustafa; Yüceer, Yonca Karagül

    2015-09-01

    The purpose of this study was to determine the physicochemical, thermal and sensorial features of vitamin enriched and aromatized hazelnut oil-beeswax and sunflower wax organogels. Another objective was to monitor the influence of storage on textural and oxidative stability and volatile composition of the organogels. The results show that organogels with beeswax had lower levels of solid fat content, melting point and firmness than sunflower wax counterparts. The microphotographs revealed that beeswax organogels had spherical crystals while sunflower wax organogels continued need-like crystals, but both organogels continued crystallized β' polymorph. All organogels maintained their oxidative stability during storage. Quantitative descriptive analysis results were consistent with these findings that the organogel structure and properties were similar to breakfast margarine. The main volatile components of the organogels with added strawberry aroma were ethyl acetate, ethyl butanoate, ethyl-2-methyl butanoate, D-limonene, ethyl caproate; banana-aroma were isoamyl acetate, isoamyl valerianate, ethyl acetate; and butter-aroma were 2,3-butanedione, 3-hydroxy-2-butanone. These volatile components were not only detected in the fresh samples but also at the end of the storage period. Sensory definition terms were matched with the sensory descriptors of the detected volatiles. In conclusion, the new organogels were shown to be suitable for food product applications.

  3. Progestogens to prevent preterm birth in twin pregnancies: an individual participant data meta-analysis of randomized trials

    Directory of Open Access Journals (Sweden)

    Schuit Ewoud

    2012-03-01

    Full Text Available Abstract Background Preterm birth is the principal factor contributing to adverse outcomes in multiple pregnancies. Randomized controlled trials of progestogens to prevent preterm birth in twin pregnancies have shown no clear benefits. However, individual studies have not had sufficient power to evaluate potential benefits in women at particular high risk of early delivery (for example, women with a previous preterm birth or short cervix or to determine adverse effects for rare outcomes such as intrauterine death. Methods/design We propose an individual participant data meta-analysis of high quality randomized, double-blind, placebo-controlled trials of progestogen treatment in women with a twin pregnancy. The primary outcome will be adverse perinatal outcome (a composite measure of perinatal mortality and significant neonatal morbidity. Missing data will be imputed within each original study, before data of the individual studies are pooled. The effects of 17-hydroxyprogesterone caproate or vaginal progesterone treatment in women with twin pregnancies will be estimated by means of a random effects log-binomial model. Analyses will be adjusted for variables used in stratified randomization as appropriate. Pre-specified subgroup analysis will be performed to explore the effect of progestogen treatment in high-risk groups. Discussion Combining individual patient data from different randomized trials has potential to provide valuable, clinically useful information regarding the benefits and potential harms of progestogens in women with twin pregnancy overall and in relevant subgroups.

  4. Purification and characterization of a novel cholesterol esterase from Pseudomonas aeruginosa, with its application to cleaning lipid-stained contact lenses.

    Science.gov (United States)

    Sugihara, Akio; Shimada, Yuji; Nomura, Atsuo; Terai, Tadamasa; Imayasu, Masaki; Nagai, Yusuke; Nagao, Toshihiro; Watanabe, Yomi; Tominaga, Yoshio

    2002-11-01

    With the aim of developing a new cholesterol esterase for eliminating lipids on used contact lenses, microorganisms were screened for the enzyme activity. A Pseudomonas aeruginosa isolated from soil was found to produce a desirable enzyme. The enzyme had an isoelectric point of 3.2, and molecular mass of 58 kDa. The optimal temperature was around 53 degrees C at pH 7.0, and the optimal pH was from 5.5 to 9.5. The enzyme was stable between pH 5 and 10 for 19 h at 25 degrees C, and retained its activity up to 53 degrees C on 30 min of incubation at pH 7.0. The rates of hydrolysis of cholesteryl esters of different fatty acids were in the following order: linoleate > oleate > stearate > palmitate > caprylate > myristate > laurate, caprate > caproate > butyrate, acetate. Addition of (tauro)cholate to a final concentration of 100 mM markedly promoted the hydrolysis of triglycerides of short-, medium-, and long-chain fatty acids. When used with taurocholate, the enzyme acted as an effective cleaner for contact lenses stained with lipids consisting of cholesteryl oleate, tripalmitin, and stearyl stearate.

  5. Simultaneous and sensitive analysis of aliphatic carboxylic acids by ion-chromatography using on-line complexation with copper(II) ion.

    Science.gov (United States)

    Kemmei, Tomoko; Kodama, Shuji; Yamamoto, Atsushi; Inoue, Yoshinori; Hayakawa, Kazuichi

    2015-01-02

    A new approach to ion chromatography is proposed to improve the UV detection of aliphatic carboxylic acids separated by anion-exchange chromatography. When copper(II) ion added to the mobile phase, it forms complexes with carboxylic acids that can be detected at 240 nm. The absorbance was found to increase with increasing copper(II) ion concentration. The retention times of α-hydroxy acids were also found to depend on the copper(II) ion concentration. Addition of acetonitrile to the mobile phase improved the separation of aliphatic carboxylic acids. The detection limits of the examined carboxylic acids (formate, glycolate, acetate, lactate, propionate, 3-hydroxypropionate, n-butyrate, isobutyrate, n-valerate, isovalerate, n-caproate) calculated at S/N=3 ranged from 0.06 to 3 μM. The detector signal was linear over three orders of magnitude of carboxylic acid concentration. The proposed method was successfully applied to analyze aliphatic carboxylic acids in rainwater and bread.

  6. RANDOMISED CONTROL STUDY OF USE OF PROGESTERONE V / S PLACEBO FOR MANAGEMENT OF SYMPTOMATIC PLACENTA PREVIA BEFORE 34 WEEKS OF GESTATION IN A TERTIARY CARE CENTRE

    Directory of Open Access Journals (Sweden)

    Shibram

    2015-04-01

    Full Text Available INTRODUCTI ON: APH complicates 3 - 5% of pregnancies and is a leading cause of perinatal and maternal mortality worldwide. Progesterone is essential in maintenance of pregnancy and helps in prolongation of pregnancy. Different trials have been done to show the efficacy and safety of progesterone in prevention of preterm birth but study related to use in expectant management of symptomatic placenta previa is very limited. AIMS AND OBJECTIVE: The objective of our study is to determine the effectiveness of intramascular 17 alpha hydroxy progesterone Caproate therapies vs. placebo in conservative management of patient with symptomatic placenta previa before 34 weeks of gestation. MATERIALS AND METHOD S: It is a randomized control study with 100 pregnant women attending Obstetric deptt. a t Nilratan Sircar Medical College and Hospital, Kolkata with symptomatic placenta previa having episode of warning haemorrhage before 34 weeks of gestation and fulfilling inclusion criteria were enrolled for the study in a two year period from January 2013 to December 2014. Statistical analysis was performed using student t - test and chai - square test where appropriate. RESULTS AND ANALYSIS: In our study prolongation of pregnancy in progesterone receiving group is statistically significant (p - value<0.001, significant difference were also found in gestational age at delivery ( p value of 0.0288, birth - weight (p - value of 0.0470. CON CLUSION: In this study use of 17 alpha hydroxy progesterone in expectant management of symptomatic placenta previa tends to be beneficial than placebo.

  7. Characterisation of the two malate dehydrogenases from Phytomonas sp. Purification of the glycosomal isoenzyme.

    Science.gov (United States)

    Uttaro, A D; Opperdoes, F R

    1997-10-01

    Two NAD(H)-dependent malate dehydrogenase (MDH) isoenzymes were detected in Phytomonas isolated from the lactiferous tubes of Euphorbia characias. The total specific activity in crude extracts using oxaloacetate as substrate was 3.3 U mg-1 of protein. The two isoenzymes had isoelectric points of 6.0 and 7.2, respectively. The acidic isoform represented 80% of the total activity in the cell and was present in the glycosome. It was purified to homogeneity by a method involving hydrophobic interaction chromatography on Phenyl-Sepharose followed by ionic exchange on CM-Sepharose and affinity chromatography on Blue-Sepharose. The purified glycosomal MDH is a homodimeric protein with a subunit molecular mass of 37 kDa and it has a low substrate specificity, since it was able to reduce both aromatic and aliphatic alpha-ketoacids as substrate including oxaloacetate, phenyl pyruvate, alpha-keto iso-caproate and pyruvate. The apparent K(m)s for oxaloacetate and NADH were 166 and 270 microM, respectively and for L-malate and NAD+, 3000 and 246 microM, respectively. The basic isoform was present in the mitochondrion. It has a high substrate specificity and an apparent K(m) of 132 and 63 microM for oxaloacetate and NADH, respectively, and of 450 and 91 microM, respectively, with L-malate and NAD+.

  8. Ruminal fermentation of propylene glycol and glycerol.

    Science.gov (United States)

    Trabue, Steven; Scoggin, Kenwood; Tjandrakusuma, Siska; Rasmussen, Mark A; Reilly, Peter J

    2007-08-22

    Bovine rumen fluid was fermented anaerobically with 25 mM R-propylene glycol, S-propylene glycol, or glycerol added. After 24 h, all of the propylene glycol enantiomers and approximately 80% of the glycerol were metabolized. Acetate, propionate, butyrate, valerate, and caproate concentrations, in decreasing order, all increased with incubation time. Addition of any of the three substrates somewhat decreased acetate formation, while addition of either propylene glycol increased propionate formation but decreased that of butyrate. R- and S-propylene glycol did not differ significantly in either their rates of disappearance or the products formed when they were added to the fermentation medium. Fermentations of rumen fluid containing propylene glycol emitted the sulfur-containing gases 1-propanethiol, 1-(methylthio)propane, methylthiirane, 2,4-dimethylthiophene, 1-(methylthio)-1-propanethiol, dipropyl disulfide, 1-(propylthio)-1-propanethiol, dipropyl trisulfide, 3,5-diethyl-1,2,4-trithiolane, 2-ethyl-1,3-dithiane, and 2,4,6-triethyl-1,3,5-trithiane. Metabolic pathways that yield each of these gases are proposed. The sulfur-containing gases produced during propylene glycol fermentation in the rumen may contribute to the toxic effects seen in cattle when high doses are administered for therapeutic purposes.

  9. A novel thermoalkalostable esterase from Acidicaldus sp. strain USBA-GBX-499 with enantioselectivity isolated from an acidic hot springs of Colombian Andes.

    Science.gov (United States)

    López, Gina; Chow, Jennifer; Bongen, Patrick; Lauinger, Benjamin; Pietruszka, Jörg; Streit, Wolfgang R; Baena, Sandra

    2014-10-01

    Several thermo- and mesoacidophilic bacterial strains that revealed high lipolytic activity were isolated from water samples derived from acidic hot springs in Los Nevados National Natural Park (Colombia). A novel lipolytic enzyme named 499EST was obtained from the thermoacidophilic alpha-Proteobacterium Acidicaldus USBA-GBX-499. The gene estA encoded a 313-amino-acid protein named 499EST. The deduced amino acid sequence showed the highest identity (58 %) with a putative α/β hydrolase from Acidiphilium sp. (ZP_08632277.1). Sequence alignments and phylogenetic analysis indicated that 499EST is a new member of the bacterial esterase/lipase family IV. The esterase reveals its optimum catalytic activity at 55 °C and pH 9.0. Kinetic studies showed that 499EST preferentially hydrolyzed middle-length acyl chains (C6-C8), especially p-nitrophenyl (p-NP) caproate (C6). Its thermostability and activity were strongly enhanced by adding 6 mM FeCl3. High stability in the presence of water-miscible solvents such as dimethyl sulfoxide and glycerol was observed. This enzyme also exhibits stability under harsh environmental conditions and enantioselectivity towards naproxen and ibuprofen esters, yielding the medically relevant (S)-enantiomers. In conclusion, according to our knowledge, 499EST is the first thermoalkalostable esterase derived from a Gram-negative thermoacidophilic bacterium.

  10. Short-chain aliphatic ester synthesis using Thermobifida fusca cutinase.

    Science.gov (United States)

    Su, Lingqia; Hong, Ruoyu; Guo, Xiaojie; Wu, Jing; Xia, Yongmei

    2016-09-01

    Short-chain aliphatic esters are commonly used as fruit flavorings in the food industry. In this study, Thermobifida fusca (T. fusca) cutinase was used for the synthesis of aliphatic esters, and the maximum yield of ethyl caproate reached 99.2% at a cutinase concentration of 50U/ml, 40°C, and water content of 0.5%, representing the highest ester yield to date. The cutinase-catalyzed esterification displayed strong tolerance for water content (up to 8%) and acid concentration (up to 0.8M). At substrate concentrations ⩽0.8M, the ester yield remained above 80%. Moreover, ester yields of more than 98% and 95% were achieved for acids of C3-C8 and alcohols of C1-C6, respectively, indicating extensive chain length selectivity of the cutinase. These results demonstrate the superior ability of T. fusca cutinase to catalyze the synthesis of short-chain esters. This study provides the basis for industrial production of short-chain esters using T. fusca cutinase.

  11. Fermentation of cottonseed and other feedstuffs in cattle rumen fluid.

    Science.gov (United States)

    Schneider, Ian C; Ames, Michael L; Rasmussen, Mark A; Reilly, Peter J

    2002-04-10

    Bovine rumen fluid was fermented anaerobically over 48 h with cottonseed, corn, alfalfa, or a mixture of these substrates in anaerobic mineral buffer. Samples taken at different incubation times were derivatized with n-butanol and subjected to gas chromatography and mass spectroscopy. No unusual fermentation end-products from the cottonseed substrate were detected. Cottonseed supported rumen fermentation at levels comparable to those of the other substrates. Major components were usually found in the decreasing order of acetate, propionate, butyrate, and valerate, although acetate and propionate concentrations decreased late in the alfalfa and mixed-feed fermentations, eventually allowing butyrate concentrations to exceed those of propionate. As expected, lactate was produced in high concentrations when corn was fermented. The minor components 2-methylpropionate, 2- and 3-methylbutyrate, phenylacetate, phenylpropionate, and caproate also accumulated, with their relative concentrations varying with the substrate. Succinate was produced in substantial amounts only when corn and alfalfa were fermented; it did not accumulate when cottonseed was the substrate. Samples containing cottonseed were derivatized and subjected to reversed-phase high-performance liquid chromatography, revealing that gossypol concentrations did not change during fermentation.

  12. 钠盐浓度对厌氧产氢颗粒污泥从蔗糖中产氢的影响%Effect of Sodium Ion Concentration on Hydrogen Production from Sucrose by Anaerobic Hydrogen-producing Granular Sludge

    Institute of Scientific and Technical Information of China (English)

    郝小龙; 周明华; 俞汉青; 沈琴琴; 雷乐成

    2006-01-01

    This work evaluated the effects of sodium ion concentration, ranging from 0 to 16000mg·L-1(Na+), on the conversion of sucrose to hydrogen by a high-activity anaerobic hydrogen-producing granular sludge. At the optimum sodium ion concentration [1000-2000mg·L-1(Na+)] for hydrogen production at 37℃, the maximum sucrose degradation rate, the specific hydrogen production yield and the specific hydrogen production rate were 393.6-413.1mg·L-1·h-1, 28.04-28.97ml·g-1, 7.52-7.83ml·g-1·h-1, respectively. The specific production yields of propionate, butyrate and valerate decreased, with increasing sodium ion concentration, whereas the specific acetate production yield increased, meanwhile the specific production yields of ethanol and caproate were less than 55.3 and 12.6mg·g-1, respectively. The hybrid fermentation composition gradually developed from acetate, propionate and butyrate to acetate with the increase in sodium ion concentration.

  13. A novel family VII esterase with industrial potential from compost metagenomic library

    Directory of Open Access Journals (Sweden)

    Oh Tae-Kwang

    2011-05-01

    Full Text Available Abstract Background Among the vast microbial genomic resources now available, most microbes are unculturable in the laboratory. A culture-independent metagenomic approach is a novel technique that circumvents this culture limitation. For the screening of novel lipolytic enzymes, a metagenomic library was constructed from compost, and the clone of estCS2 was selected for lipolytic properties on a tributyrin-containing medium. Results The estCS2 sequence encodes a protein of 570 amino acid residues, with a predicted molecular mass of 63 kDa, and based on amino acid identity it most closely matches (45% the carboxylesterase from Haliangium ochraceum DSM 14365. EstCS2 belong to family VII, according to the lipolytic enzyme classification proposed by Arpigny and Jaeger, and it retains the catalytic triad Ser245-Glu363-His466 that is typical of an α/β hydrolase. The Ser245 residue in the catalytic triad of EstCS2 is located in the consensus active site motif GXSXG. The EstCS2 exhibits strong activity toward p-nitrophenyl caproate (C6, and it is stable up to 60°C with an optimal enzymatic activity at 55°C. The maximal activity is observed at pH 9, and it remains active between pH 6-10. EstCS2 shows remarkable stability in up to 50% (v/v dimethyl sulfoxide (DMSO or dimethylformamide (DMF. The enzyme has the ability to cleave sterically hindered esters of tertiary alcohol, as well as to degrade polyurethanes, which are widely used in various industries. Conclusions The high stability of EstCS2 in organic solvents and its activity towards esters of ketoprofen and tertiary alcohols, and in polyurethane suggests that it has potential uses for many applications in biotransformation and bioremediation.

  14. Occurrence, absorption and metabolism of short chain fatty acids in the digestive tract of mammals.

    Science.gov (United States)

    Bugaut, M

    1987-01-01

    Short chain fatty acids (SCFA) also named volatile fatty acids, mainly acetate, propionate and butyrate, are the major end-products of the microbial digestion of carbohydrates in the alimentary canal. The highest concentrations are observed in the forestomach of the ruminants and in the large intestine (caecum and colon) of all the mammals. Butyrate and caproate released by action of gastric lipase on bovine milk triacylglycerols ingested by preruminants or infants are of nutritional importance too. Both squamous stratified mucosa of rumen and columnar simple epithelium of intestine absorb readily SCFA. The mechanisms of SCFA absorption are incompletely known. Passive diffusion of the unionized form across the cell membrane is currently admitted. In the lumen, the necessary protonation of SCFA anions could come first from the hydration of CO2. The ubiquitous cell membrane process of Na+-H+ exchange can also supply luminal protons. Evidence for an acid microclimate (pH = 5.8-6.8) suitable for SCFA-protonation on the surface of the intestinal lining has been provided recently. This microclimate would be generated by an epithelial secretion of H+ ions and would be protected by the mucus coating from the variable pH of luminal contents. Part of the absorbed SCFA does not reach plasma because it is metabolized in the gastrointestinal wall. Acetate incorporation in mucosal higher lipids is well-known. However, the preponderant metabolic pathway for all the SCFA is catabolism to CO2 except in the rumen wall where about 80% of butyrate is converted to ketone bodies which afterwards flow into bloodstream. Thus, SCFA are an important energy source for the gut mucosa itself.

  15. Role of mitochondrial transamination in branched chain amino acid metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Hutson, S.M.; Fenstermacher, D.; Mahar, C.

    1988-03-15

    Oxidative decarboxylation and transamination of 1-/sup 14/C-branched chain amino and alpha-keto acids were examined in mitochondria isolated from rat heart. Transamination was inhibited by aminooxyacetate, but not by L-cycloserine. At equimolar concentrations of alpha-ketoiso(1-/sup 14/C)valerate (KIV) and isoleucine, transamination was increased by disrupting the mitochondria with detergent which suggests transport may be one factor affecting the rate of transamination. Next, the subcellular distribution of the aminotransferase(s) was determined. Branched chain aminotransferase activity was measured using two concentrations of isoleucine as amino donor and (1-/sup 14/C)KIV as amino acceptor. The data show that branched chain aminotransferase activity is located exclusively in the mitochondria in rat heart. Metabolism of extramitochondrial branched chain alpha-keto acids was examined using 20 microM (1-/sup 14/C)KIV and alpha-ketoiso(1-/sup 14/C)caproate (KIC). There was rapid uptake and oxidation of labeled branched chain alpha-keto acid, and, regardless of the experimental condition, greater than 90% of the labeled keto acid substrate was metabolized during the 20-min incubation. When a branched chain amino acid (200 microM) or glutamate (5 mM) was present, 30-40% of the labeled keto acid was transaminated while the remainder was oxidized. Provision of an alternate amino acceptor in the form of alpha-keto-glutarate (0.5 mM) decreased transamination of the labeled KIV or KIC and increased oxidation. Metabolism of intramitochondrially generated branched chain alpha-keto acids was studied using (1-/sup 14/C)leucine and (1-/sup 14/C)valine. Essentially all of the labeled branched chain alpha-keto acid produced by transamination of (1-/sup 14/C)leucine or (1-/sup 14/C)valine with a low concentration of unlabeled branched chain alpha-keto acid (20 microM) was oxidized.

  16. Comparative genome analysis of Megasphaera sp. reveals niche specialization and its potential role in the human gut.

    Directory of Open Access Journals (Sweden)

    Sudarshan Anand Shetty

    Full Text Available With increasing number of novel bacteria being isolated from the human gut ecosystem, there is a greater need to study their role in the gut ecosystem and their effect on the host health. In the present study, we carried out in silico genome-wide analysis of two novel Megasphaera sp. isolates NM10 (DSM25563 and BL7 (DSM25562, isolated from feces of two healthy individuals and validated the key features by in vitro studies. The analysis revealed the general metabolic potential, adaptive features and the potential effects of these isolates on the host. The comparative genome analysis of the two human gut isolates NM10 and BL7 with ruminal isolate Megasphaera elsdenii (DSM20460 highlighted the differential adaptive features for their survival in human gut. The key findings include features like bile resistance, presence of various sensory and regulatory systems, stress response systems, membrane transporters and resistance to antibiotics. Comparison of the "glycobiome" based on the genomes of the ruminal isolate with the human gut isolates NM10 and BL revealed the presence of diverse and unique sets of Carbohydrate-Active enzymes (CAZymes amongst these isolates, with a higher collection of CAZymes in the human gut isolates. This could be attributed to the difference in host diet and thereby the environment, consequently suggesting host specific adaptation in these isolates. In silico analysis of metabolic potential predicted the ability of these isolates to produce important metabolites like short chain fatty acids (butyrate, acetate, formate, and caproate, vitamins and essential amino acids, which was further validated by in vitro experiments. The ability of these isolates to produce important metabolites advocates for a potential healthy influence on the host. Further in vivo studies including transcriptomic and proteomic analysis will be required for better understanding the role and impact of these Megasphaera sp. isolates NM10 and BL7 on the

  17. Corn steep liquor and fermented ammoniated condensed whey as protein sources for lactating cows and yearling heifers grazing winter native range

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, J.J.; Lusby, K.S.; Horn, G.W.; Dvorak, M.J.

    1982-06-01

    Corn steep liquor (CSL) and fermented ammoniated condensed whey (FACW) were compared to cottonseed meal (CSM) as protein sources for wintering 61 lactating first-calf Hereford heifers and 32 yearling Hereford heifers on native range. Cattle were allotted by weight and individually fed 6 days per week for 12 weeks one of four protein treatments: negative control (NC), positive control (PC), CSL and FACW to provide .7, 1.5, .15 and 1.5 lb crude protein (CP) per day, respectively, to the lacating heifers and .2, .4, .4 and .4lb cP per day, respectively, to the yearling heifers. CMS was supplied in the CSL and FACW treatments at the same level as in the negative control. Lactating heifers fed the NC lost more (P less than .005) weight and body condition (120 lb and 1.6 units) than those fed the PC (45.8 lb and .9 units). Weight and condition losses were similar (P more than .05) for lactating heifers fed PC, CSL and FACW. Yearling heifers fed the NC lost more (P less than .005) weight than those fed the PC (49.4 vs 10.6 lb). Yearling heifers fed CSL and FACW gained more (P less than .005) weight than those fed the PC (17.6 and 9.3 vs - 10.6 lb). Feeding CSL resulted in signficantly lower rumen pH, lower ruminal acetate and higher ruminal butyrate, isovalerate and caproate levels than did feeding either control. Supplementing with FACW produced significantly lower rumen pH, higher rumen ammonia and soluble carbohydrate levels, lower ruminal acetate, and higher ruminal propionate and butyrate concentrations than did either control supplement. Corn steep liquor and FDCW appear to be effective protein sources for cows and heifers grazing winter native range.

  18. Mesophilic and thermophilic conditions select for unique but highly parallel microbial communities to perform carboxylate platform biomass conversion.

    Directory of Open Access Journals (Sweden)

    Emily B Hollister

    Full Text Available The carboxylate platform is a flexible, cost-effective means of converting lignocellulosic materials into chemicals and liquid fuels. Although the platform's chemistry and engineering are well studied, relatively little is known about the mixed microbial communities underlying its conversion processes. In this study, we examined the metagenomes of two actively fermenting platform communities incubated under contrasting temperature conditions (mesophilic 40°C; thermophilic 55 °C, but utilizing the same inoculum and lignocellulosic feedstock. Community composition segregated by temperature. The thermophilic community harbored genes affiliated with Clostridia, Bacilli, and a Thermoanaerobacterium sp, whereas the mesophilic community metagenome was composed of genes affiliated with other Clostridia and Bacilli, Bacteriodia, γ-Proteobacteria, and Actinobacteria. Although both communities were able to metabolize cellulosic materials and shared many core functions, significant differences were detected with respect to the abundances of multiple Pfams, COGs, and enzyme families. The mesophilic metagenome was enriched in genes related to the degradation of arabinose and other hemicellulose-derived oligosaccharides, and the production of valerate and caproate. In contrast, the thermophilic community was enriched in genes related to the uptake of cellobiose and the transfer of genetic material. Functions assigned to taxonomic bins indicated that multiple community members at either temperature had the potential to degrade cellulose, cellobiose, or xylose and produce acetate, ethanol, and propionate. The results of this study suggest that both metabolic flexibility and functional redundancy contribute to the platform's ability to process lignocellulosic substrates and are likely to provide a degree of stability to the platform's fermentation processes.

  19. Progesterone for the prevention of preterm birth in women with multiple pregnancies: the AMPHIA trial

    Directory of Open Access Journals (Sweden)

    Scheepers Hubertina CJ

    2007-06-01

    Full Text Available Abstract Background 15% of multiple pregnancies ends in a preterm delivery, which can lead to mortality and severe long term neonatal morbidity. At present, no generally accepted strategy for the prevention of preterm birth in multiple pregnancies exists. Prophylactic administration of 17-alpha hydroxyprogesterone caproate (17OHPC has proven to be effective in the prevention of preterm birth in women with singleton pregnancies with a previous preterm delivery. At present, there are no data on the effectiveness of progesterone in the prevention of preterm birth in multiple pregnancies. Methods/Design We aim to investigate the hypothesis that 17OHPC will reduce the incidence of the composite neonatal morbidity of neonates by reducing the early preterm birth rate in multiple pregnancies. Women with a multiple pregnancy at a gestational age between 15 and 20 weeks of gestation will be entered in a placebo-controlled, double blinded randomised study comparing weekly 250 mg 17OHPC intramuscular injections from 16–20 weeks up to 36 weeks of gestation versus placebo. At study entry, cervical length will be measured. The primary outcome is composite bad neonatal condition (perinatal death or severe morbidity. Secondary outcome measures are time to delivery, preterm birth rate before 32 and 37 weeks, days of admission in neonatal intensive care unit, maternal morbidity, maternal admission days for preterm labour and costs. We need to include 660 women to indicate a reduction in bad neonatal outcome from 15% to 8%. Analysis will be by intention to treat. We will also analyse whether the treatment effect is dependent on cervical length. Discussion This trial will provide evidence as to whether or not 17OHPC-treatment is an effective means of preventing bad neonatal outcome due to preterm birth in multiple pregnancies. Trial registration Current Controlled Trials ISRCTN40512715

  20. Non-targeted and targeted analysis of wild toxic and edible mushrooms using gas chromatography-ion trap mass spectrometry.

    Science.gov (United States)

    Carvalho, Luís Miguel; Carvalho, Félix; de Lourdes Bastos, Maria; Baptista, Paula; Moreira, Nathalie; Monforte, Ana Rita; da Silva Ferreira, António César; de Pinho, Paula Guedes

    2014-01-01

    Mushrooms are known all over the world both due to the remarkable gastronomic value of some species and for severe intoxications mediated by other species that are frequently difficult to distinguish from the edible ones, by the common user. Therefore, it is important to develop strategies to discover molecules that can identify mushroom species. In the present work, two GC-MS methodologies were applied in the chemical characterization of 22 mushroom species (12 edible, 3 toxic and 7 potentially toxic) - a multi-target procedure to simultaneously determine amino acids (AA), fatty acids (FA) and sterols by previous derivatization procedure with MSTFA, and a Head Space-Solid Phase Microextraction method to determine volatiles. For both methods, two approaches to data analysis were used: (I) targeted analysis, to identify and quantify AA, FA sterols and volatiles; (II) untargeted analysis, including Principal Component Analysis and Partial Least Square Discriminant Analysis, in order to identify metabolites/metabolite pattern with potential species identification and/or differentiation. Multi-target experiment allowed the identification and quantification of twenty one primary metabolites (9 AA, 11 FA and 1 sterol). Furthermore, through untargeted data analysis, it was possible to identify a 5-carbon sugar alcohol structure molecule, which was tentatively identified as xylitol or adonitol, with potential to be a species-marker of the edible Suillus bovinus mushrooms. Volatile profiling studies resulted in the identification of the main volatiles in mushrooms. Untargeted analysis allowed the identification of 6 molecules that can be species- or genus-specific: one secondary metabolite specific to the edible species Lycoperdon perlatum, an ester of hexanoic acid, tentatively identified as allyl or vinyl caproate; and five other secondary metabolites, whose identification was not achieved, which were only detected in Lactarius aurantiacus specimens (edibility

  1. Production of bio-hydrogen by mesophilic anaerobic fermentation in an acid-phase sequencing batch reactor.

    Science.gov (United States)

    Cheong, Dae-Yeol; Hansen, Conly L; Stevens, David K

    2007-02-15

    The pH and hydraulic retention time (HRT) of an anaerobic sequencing batch reactor (ASBR) were varied to optimize the conversion of carbohydrate-rich synthetic wastewater into bio-hydrogen. A full factorial design using evolutionary operation (EVOP) was used to determine the effect of the factors and to find the optimum condition of each factor required for high hydrogen production rate. Experimental results from 20 runs indicate that a maximum hydrogen production rate of 4,460-5,540 mL/L/day under the volumetric organic loading rate (VOLR) of 75 g-COD/L/day obtained at an observed design point of HRT = 8 h and pH = 5.7. The hydrogen production rate was strongly dependent on the HRT, and the effect was statistically significant (P 0.05) was found for the pH on the hydrogen production rate. When the ASBR conditions were set for a maximum hydrogen production rate, the hydrogen production yield and specific hydrogen production rate were 60-74 mL/g-COD and 330-360 mL/g-VSS/day, respectively. The hydrogen composition was 43-51%, and no methanogenesis was observed. Acetate, propionate, butyrate, valerate, caproate, and ethanol were major liquid intermediate metabolites during runs of this ASBR. The dominant fermentative types were butyrate-acetate or ethanol-acetate, representing the typical anaerobic pathway of Clostridium species. This hydrogen-producing ASBR had a higher hydrogen production rate, compared with that produced using continuous-flow stirred tank reactors (CSTRs). This study suggests that the hydrogen-producing ASBR is a promising bio-system for prolonged and stable hydrogen production.

  2. A narrow pH range supports butanol, hexanol, and octanol production from syngas in a continuous co-culture of Clostridium ljungdahlii and Clostridium kluyveri with in-line product extraction

    Directory of Open Access Journals (Sweden)

    Hanno Richter

    2016-11-01

    Full Text Available Carboxydotrophic bacteria (CTB have received attention due to their ability to synthesize commodity chemicals from producer gas and synthesis gas (syngas. CTB have an important advantage of a high product selectivity compared to chemical catalysts. However, the product spectrum of wild-type CTB is narrow. Our objective was to investigate whether a strategy of combining two wild-type bacterial strains into a single, continuously fed bioprocessing step would be promising to broaden the product spectrum. Here, we have operated a syngas-fermentation process with Clostridium ljungdahlii and Clostridium kluyveri with in-line product extraction through gas stripping and product condensing within the syngas recirculation line. The main products from C. ljungdahlii fermentation at a pH of 6.0 were ethanol and acetate at net volumetric production rates of 65.5 and 431 mmol C•L-1•d-1, respectively. An estimated 2/3 of total ethanol produced was utilized by C. kluyveri to chain elongate with the reverse β-oxidation pathway, resulting in n-butyrate and n-caproate at net rates of 129 and 70 mmol C•L-1•d-1, respectively. C. ljungdahlii likely reduced the produced carboxylates to their corresponding alcohols with the reductive power from syngas. This resulted in the longer-chain alcohols n-butanol, n-hexanol, and n-octanol at net volumetric production rates of 39.2, 31.7, and 0.045 mmol C•L-1•d-1, respectively. The continuous production of the longer-chain alcohols occurred only within a narrow pH spectrum of 5.7-6.4 due to the pH discrepancy between the two strains. Regardless whether other wild-type strains could overcome this pH discrepancy, the specificity (mol carbon in product per mol carbon in all other liquid products for each longer-chain alcohol may never be high in a single bioprocessing step. This, because two bioprocesses compete for intermediates (i.e., carboxylates: 1 chain elongation; and 2 biological reduction. This innate

  3. Brewing Technology of Persimmon plus Hawthorn Fruit Wine%柿子、山楂复合果酒的研制

    Institute of Scientific and Technical Information of China (English)

    莫海珍; 张天英; 曾辉; 杨宁; 张浩

    2013-01-01

    In this study, water persimmon from Huixian of Henan province and red hawthorn from northern Henan province were used as the raw materials to optimize the brewing technology of persimmon +hawthorn complex fruit wine.Water persimmon was used as the foundation, and the pH-value of fruit pulp was adjusted respectively to 3.2, 3.6, 4.0 and 5.0 by hawthorn with higher organic acid content .The change rule of the main compositions in the fermentation process as well as the flavor of the finished product wine were studied.The results showed that:when the pH-value of fruit pulp was adjusted to 3.6 by hawthorn, the taste of the complex fruit wine was delicious , sweet and scented, and its aroma components mainly included some esters , such as ethyl ace-tate and ethyl caproate.The products had good biological stability with clear and transparent appearance .%  利用河南辉县水柿和豫北红山楂作为原料酿制柿子山楂酒,以水柿为基础,采用有机酸含量较高的山楂调节果浆pH值分别至3.2、3.6、4.0和5.0,研究发酵过程中主要成分的变化规律以及成品酒的风味,结果显示:采用山楂果浆调节pH值至3.6的柿子山楂酒的口感圆润、香气浓郁,香气组分主要以乙酸乙酯和己酸乙酯等酯类为主,产品生物稳定性好、澄清透明。

  4. The Best Treatment Effects of Active Carbon on Low-alcohol Liquor of Different Alcoholicity%不同酒度低度白酒活性炭处理最佳效果

    Institute of Scientific and Technical Information of China (English)

    代汉聪; 张宿义; 谢明; 李云辉

    2012-01-01

    对不同酒度低度白酒活性炭除浊、香味损失及化学性能等指标进行了研究。结果表明,同一酒度白酒进行活性炭处理,随着活性炭用量的增加,酒中己酸乙酯、乳酸乙酯、乙酸乙酯、丁酸乙酯等色谱骨架成分及棕榈酸乙酯、亚油酸乙酯、油酸乙酯等高级脂肪酸乙酯的含量均有一定程度的降低;总酸、总酯也随着活性炭添加量的增加有一定程度减小,且酒质香浓感减弱,酒体抗冻能力增强。用同量活性炭对不同酒度白酒进行处理,酒度越高,其处理降度后的低度白酒微量香味成分越丰富,酒质香浓感越好,但酒体抗冻能力越弱。新处理工艺能够增加酒体香浓感,且大幅度提升酒体口感质量。%Active carbon was used for turbidity-removal of low-alcohol liquor of different alcoholicity,and the loss of liquor aroma and the change in its chemical indexes were studied.The results indicated that,for liquor of the same alcoholicity,with the increase of active carbon use level,the content of ethyl caproate,ethyl lactate,ethyl acetate,ethyl butyrate,palmitic acid ethyl ester,ethyl linoleate,ethyl oleate and other higher fatty ethyl esters reduced to some extent in the liquor,the content of total acids and total esters also decreased and liquor aroma weakened,however,liquor antifreeze capacity enhanced;for liquor of different alcoholicity but treated by the same use level of active carbon,the higher of liquor alcoholicity,the richer of trace flavoring components in treated liquor and the better of liquor quality and liquor aroma,however,the weaker of liquor antifreeze capacity.The new processing techniques could enhance the aroma of liquor body and greatly improve liquor taste and liquor quality.

  5. Breeding research on sake yeasts in Japan: history, recent technological advances, and future perspectives.

    Science.gov (United States)

    Kitagaki, Hiroshi; Kitamoto, Katsuhiko

    2013-01-01

    Sake is an alcoholic beverage of Japan, with a tradition lasting more than 1,300 years; it is produced from rice and water by fermenting with the koji mold Aspergillus oryzae and sake yeast Saccharomyces cerevisiae. Breeding research on sake yeasts was originally developed in Japan by incorporating microbiological and genetic research methodologies adopted in other scientific areas. Since the advent of a genetic paradigm, isolation of yeast mutants has been a dominant approach for the breeding of favorable sake yeasts. These sake yeasts include (a) those that do not form foams (produced by isolating a mutant that does not stick to foams, thus decreasing the cost of sake production); (b) those that do not produce urea, which leads to the formation of ethyl carbamate, a possible carcinogen (isolated by positive selection in a canavanine-, arginine-, and ornithine-containing medium); (c) those that produce an increased amount of ethyl caproate, an apple-like flavor (produced by isolating a mutant resistant to cerulenin, an inhibitor of fatty-acid synthesis); and (d) those that produce a decreased amount of pyruvate (produced by isolating a mutant resistant to an inhibitor of mitochondrial transport, thus decreasing the amount of diacetyl). Given that sake yeasts perform sexual reproduction, sporulation and mating are potent approaches for their breeding. Recently, the genome sequences of sake yeasts have been determined and made publicly accessible. By utilizing this information, the quantitative trait loci (QTLs) for the brewing characteristics of sake yeasts have been identified, which paves a way to DNA marker-assisted selection of the mated strains. Genetic engineering technologies for experimental yeast strains have recently been established by academic groups, and these technologies have also been applied to the breeding of sake yeasts. Sake yeasts whose genomes have been modified with these technologies correspond to genetically modified organisms (GMOs

  6. A novel alkaliphilic bacillus esterase belongs to the 13(th bacterial lipolytic enzyme family.

    Directory of Open Access Journals (Sweden)

    Lang Rao

    Full Text Available BACKGROUND: Microbial derived lipolytic hydrolysts are an important class of biocatalysts because of their huge abundance and ability to display bioactivities under extreme conditions. In spite of recent advances, our understanding of these enzymes remains rudimentary. The aim of our research is to advance our understanding by seeking for more unusual lipid hydrolysts and revealing their molecular structure and bioactivities. METHODOLOGY/PRINCIPAL FINDINGS: Bacillus. pseudofirmus OF4 is an extreme alkaliphile with tolerance of pH up to 11. In this work we successfully undertook a heterologous expression of a gene estof4 from the alkaliphilic B. pseudofirmus sp OF4. The recombinant protein called EstOF4 was purified into a homologous product by Ni-NTA affinity and gel filtration. The purified EstOF4 was active as dimer with the molecular weight of 64 KDa. It hydrolyzed a wide range of substrates including p-nitrophenyl esters (C2-C12 and triglycerides (C2-C6. Its optimal performance occurred at pH 8.5 and 50°C towards p-nitrophenyl caproate and triacetin. Sequence alignment revealed that EstOF4 shared 71% identity to esterase Est30 from Geobacillus stearothermophilus with a typical lipase pentapeptide motif G91LS93LG95. A structural model developed from homology modeling revealed that EstOF4 possessed a typical esterase 6α/7β hydrolase fold and a cap domain. Site-directed mutagenesis and inhibition studies confirmed the putative catalytic triad Ser93, Asp190 and His220. CONCLUSION: EstOF4 is a new bacterial esterase with a preference to short chain ester substrates. With a high sequence identity towards esterase Est30 and several others, EstOF4 was classified into the same bacterial lipolytic family, Family XIII. All the members in this family originate from the same bacterial genus, bacillus and display optimal activities from neutral pH to alkaline conditions with short and middle chain length substrates. However, with roughly 70% sequence

  7. Effects of feed additives on rumen and blood profiles during a starch and fructose challenge.

    Science.gov (United States)

    Golder, H M; Celi, P; Rabiee, A R; Lean, I J

    2014-02-01

    We evaluated the effect of feed additives on the risk of ruminal acidosis in Holstein heifers (n = 40) fed starch and fructose in a challenge study. Heifers were randomly allocated to feed additive groups (n = 8 heifers/group): (1) control (no additives); (2) virginiamycin (VM); (3) monensin + tylosin (MT); (4) monensin + live yeast (MLY); and (5) sodium bicarbonate + magnesium oxide (BUF). Heifers were fed 2.5% of body weight (BW) dry matter intake (DMI) per day of a total mixed ration (62:38 forage:concentrate) and feed additives for a 20-d adaptation period. Fructose (0.1% of BW/d) was included for the last 10d of the adaptation period. On d 21, heifers were fed to target a DMI of 1.0% of BW of wheat, fructose at 0.2% of BW, and their feed additives. Rumen fluid samples obtained by stomach tube and blood samples were collected weekly as well as during a 3.6-h period on challenge day (d 21). Virginiamycin and BUF groups maintained a consistently high DMI across the 20-d adaptation period. The MLY heifers had low DMI of the challenge ration. Average daily gain and feed conversion ratio were not affected by feed additives. All rumen and plasma measures changed weekly over adaptation and over the challenge sampling period with the exception of rumen total lactate and histamine concentrations, plasma oxidative stress index, and ceruloplasmin. Substantial within- and between-group variation was observed in rumen and plasma profiles at challenge sampling. No significant group changes were observed in rumen total volatile fatty acids, propionate, acetate-to-propionate ratio, isobutyrate, caproate, isovalerate, total lactate, d- and l-lactate, and pH measures on challenge day. Acetate concentration was increased in the BUF and control groups on challenge day. Butyrate concentration was lower in the MLY and MT groups compared with other groups at challenge. Valerate concentrations were lowest in the control, VM, and BUF groups and lactate concentrations were numerically

  8. Rhizopus arrhizus Lipase Catalyzed Syntheses of Three Esters in Nonaqueous Solvents%非水溶剂中Rhizopus arrhizus脂肪酶催化合成三种酯的最佳条件

    Institute of Scientific and Technical Information of China (English)

    杨本宏; 吴克; 刘斌; 郑敏; 蔡敬民; 潘仁瑞

    2003-01-01

    以少根根霉(Rhizopus arrhizus)脂肪酶为催化剂,有机溶剂为反应介质,合成了3种短链脂肪酸酯.研究了反应温度、溶剂、底物浓度、底物摩尔比、吸水剂用量等因素对酯化反应的影响.确定了3种酯的最佳合成条件:(1)己酸乙酯:反应温度为40℃,环己烷为溶剂,0.25 mol/L底物浓度,酸醇摩尔比为1∶1.2;(2)乙酸异丙酯:50℃,环己烷为溶剂,0.15 mol/L底物浓度,摩尔比为1∶1;(3)乙酸异戊酯:50℃,异辛烷为溶剂,0.20 mol/L底物浓度,摩尔比为1∶1. 三种酯合成时均需0.125 g/ml的0.5 nm分子筛为吸水剂,在8 h后,合成酯转化率达到97%~99%.%The Rhizopus arrhizus lipase catalyzed syntheses of three short-chain esters in organic solvents were studied. The optimum conditions for each esterification were determined as follows: (1)ethyl caproate: synthesized in cyclohexane at 40℃ with 0.25 mol/L substrate and 1∶1.2 acid-alcohol molar ratio; (2)isopropyl acetate: reacted in cyclohexane at 50℃ with 0.15 mol/L substrate and 1∶1 molar ratio; (3)isoamyl acetate: in isooctane at 50℃ with 0.20 mol/L substrate, and 1∶1 molar ratio. 0.125 g per ml of 0.5 nm molecular sieve was required as adsorbent for water in the reactions. Under the optimal conditions, the yields reached 97%-99% after incubation for 8 hours.

  9. Volatile Flavoring Compounds in Beer Produced by Wheat Extruded at Low Temperature as Auxiliary Materials%低温挤压小麦辅料啤酒挥发性风味组分分析

    Institute of Scientific and Technical Information of China (English)

    何媛媛; 郑慧; 李宏军

    2015-01-01

    In this study, quantitative&qualitative analysis of the volatile flavoring compounds in beer produced by wheat extruded at low tem-perature as auxiliary materials was done by automatic head-space sampling coupled with capillary gas chromatography. The results showed that, 8 main volatile flavoring compounds were isolated from beer including acetaldehyde, n-propanol, ethyl acetate, isobutanol, isoamyl alco-hol, isoamyl acetate, ethyl caproate and ethyl caprylate. The content of each volatile flavoring compounds were in the range of normal content of light beer. The variation coefficients of the analytic results were less than 5%and the recoveries were more than 95%, which proved good repeatability and accuracy of such method. The content of total soluble nitrogen and high, middle and low-molecular nitrogenous substances in beer detected by Lundin fraction method were 105.1 mg/100 mL, 13.9 mg/100 mL, 20.0 mg/100 mL and 71.2 mg/100 mL, respectively.%采用静态自动顶空进样结合毛细管气相色谱法对膨化小麦辅料啤酒的挥发性风味组分进行定性和定量分析。结果表明,从膨化小麦辅料啤酒中主要分离出8种挥发性风味组分,其组分及含量分别是乙醛、正丙醇、乙酸乙酯、异丁醇、异戊醇、乙酸异戊酯、己酸乙酯和辛酸乙酯。啤酒中各挥发性风味组分的含量均在淡色啤酒正常含量范围之内。该方法测量结果变异系数均小于5%,回收率均大于95%,具有很好的准确性和重复性。用隆丁区分法测量小麦辅料啤酒中总氮和高、中、低分子氮的含量分别为总可溶性氮105.1 mg/100 mL、高分子氮13.9 mg/100 mL、中分子氮20.0 mg/100 mL、低分子氮71.2 mg/100 mL。

  10. 啤酒发酵过程对重要醇酯影响的研究%The Effects of Beer Fermentation on the Content of Higher Alcohols and Esters

    Institute of Scientific and Technical Information of China (English)

    钟成; 杨攀飞; 刘伶普; 郝俊光; 贾士儒

    2015-01-01

    风味物质的含量决定啤酒的品质,其特征会直接决定啤酒口感和其市场竞争力。研究了麦汁浓度、主酵温度和接种量对啤酒中风味物质的影响。在不同的发酵条件下,以全麦芽为原料,经下面发酵生产啤酒。采用顶空气相色谱法检测啤酒中高级醇和酯类的浓度。研究发现麦汁浓度对高级醇和酯的影响最大,且提高麦汁浓度能够同时增大啤酒中高级醇和酯的含量,当麦汁浓度从11°P提高到15°P,乙酸乙酯的含量提高了34%。在相同接种量和麦汁浓度下,主酵温度越高,异戊醇含量越高,异丁醇的含量却有所降低。在较高的发酵温度下乙酸乙酯、辛酸乙酯和乙酸异戊酯的含量升高,但是己酸乙酯的含量变化无规律。研究结果显示接种量对醇和酯的影响都不显著。%The content of flavoring substances determines the quality of beer and the flavoring characteristics will directly determine the taste and market competitiveness of beer product. In this study, the effects of wort concentration, chief fermenting temperature and barm inoculating quantity on flavoring substances in beer were investigated. In the experiments, beer was produced with whole malt as raw materials by bottom fermentation under different fermenting conditions. The content of higher alcohols and esters were detected by HS-GC. The experimental re-sults suggested that wort concentration among the three factors had the greatest effects on higher alcohols & esters content. The enhance of wort concentration could increase both higher alcohols content and esters content at the same time. As wort concentration got enhanced from 11° P to 15° P, the content of ethyl caproate increased by 34%. Under the conditions of the same barm inoculating quantity and the same wort concentration, higher chief fermenting temperature might induce higher content of isoamylol but lower content of isobutanol. The content of

  11. 3种芦丁脂肪酸酯在空气/水界面的成膜性质%Monolayers of Three Amphiphilic Esters of Rutin at the Air-water Interface

    Institute of Scientific and Technical Information of China (English)

    段煜; 杜宗良; 李瑞霞; 吴大诚

    2011-01-01

    The π - A isotherms for monolayers of three amphiphilic rutin esters, rutin - 4''' - 0 - stearate ( RS ), rutin - 4''' - 0 -laurate (RL) and rutin -4''' -0 -caproate (RC), were measured at the air-water interface and air-aqueous aluminum sulfate solution interface.The properties of the monolayers of three rutin esters were related to the carbon number of alkyl, the compression rate and the property of substrate.Although RS and RL showed scant water solubility, they formed monolayers with the liquid-expanded phase when spread on water.While RC could not form insoluble monolayer at the air-water interface, which may be due to the larger water solubility of RC.Appropriately low compression rate was critical to the formation of relatively stable monolayers.When spread on an aqueous aluminum sulfate solution, the formation of a complex between the aluminum ions and the rutin ester resulted in higher values of acoll for RS and RL monolayers compared with their values on water, and RC could spread as liquid-expanded phase monolayer.The present results provided valuable information for investigating the interaction of flavonoids and biomembranes and the anti-oxidant mechanism of flavonoids.%采用LB膜分析仪分别研究了芦丁硬脂酸酯(RS)、芦丁月桂酸酯(RL)和芦丁正己酸酯(RC)在空气/水界面的成膜性质,及亚相中的Al3+对3种芦丁脂肪酸酯成膜性质的影响.结果显示,3种芦丁脂肪酸酯的成膜性质与其疏水基的碳链长度、压膜速度和亚相性质有关.RS和RL能在水面铺展为液态扩张膜,RC则不能成膜.引入芦丁分子中的疏水基碳链越长,成膜越稳定.慢速压膜利于膜稳定性,膜的崩溃压大;较快速压膜能使更多膜分子保留在水表面,膜的平均分子面积大.选择适宜的压膜速度对得到比较稳定的芦丁脂肪酸酯膜很关键.当亚相中含Al3+时,RS、RL和RC均铺展成液态扩张膜,且RS膜和RL膜崩溃时的分子面积(acoll)大于它们在水表

  12. 一株窖泥己酸菌株的多相鉴定及产酸研究%Polyphasic Identification of a Hexanoic Acid Bacteria Strain from the Pit Mud and Study on Its Acid Producing Ability

    Institute of Scientific and Technical Information of China (English)

    薛正楷; 薛原

    2016-01-01

    Polyphasic identification of a combination of morphological observation, physiological&biochemical indexes, 16s RNA gene se-quencing analysis was adopted to identify a hexanoic-acid-producing bacteria strain K-2 (isolated from the mud of 180-year-old pit). Then the metabolites of this strain were analyzed by GC. The results showed that, K-2 could utilize various carbon sources including D-glucose, manni-tol, inulin, L-arabinose, D-sucrose and it had hydrolysis activities of urease, esculin and gelatin. 16s RNA gene sequence (1346 bp) of strain K-2 showed the identity of 99%to Clostridium celerecrescens by NCBI blast, and phylogenetic analysis based on 16S rRNA gene sequence posi-tioned K-2 in the Clostridium branch, thus we identified it to be Clostridium celerecrescens. Besides, K-2 demonstrated a highly-efficient capa-bility of producing hexanoic acid (547.26 mg/100 mL) and butyric acid (382.45 mg/100 mL) , but it hardly produced ethyl caproate and ethyl butyrate. This study was the first report at home and abroad on a hexanoic-acid-producing Clostridium celerecrescens strain isolated from Non-gxiang Baijiu pit mud.%采用常规形态、生理生化指标,并结合16s RNA基因序列分析进行多相鉴定方法及气相色谱分析技术,对分离自泸州老窖180年窖池的1株产己酸菌株(K-2)进行分类鉴定和代谢产物分析,结果表明,K-2菌株能利用D-葡萄糖、甘露醇、菊糖、L-阿拉伯糖、D-蔗糖等多种碳源,具有脲酶、七叶灵和明胶酶水解活性;K-2菌株16s RNA基因序列(1346bp)与Clostridium celerecrescens一致率为99%,Strain K-216s RNA基因序列在系统进化树中位于Clostridium属分支,与Clostridium celerecrescens序列相似性最近,本研究将其鉴定为梭菌属(GenusI Clostrid-ium)中的Clostridium celerecrescens菌株,该菌株有高效的产己酸(547.26 mg/100 mL)和丁酸能力(382.45 mg/100 mL)能力,但几乎不产己酸乙酯和丁酸乙酯.此研究为国内外首次报道从浓香

  13. 山刺番荔枝果实发育进程中挥发性成分的组成分析%Analysis of volatile components in Annona montana fruit at different developmental stages

    Institute of Scientific and Technical Information of China (English)

    徐子健; 龙娅丽; 江雪飞; 乔飞; 党志国; 陈业渊

    2016-01-01

    -SPME-GC/MS.Flesh of green fruit,degreening fruit and ripe fruit was sampled and quickly frozen in liquid nitrogen and then preserved in-80 ℃.15 g of the finely powdered flesh samples was transferred into a 40 mL Teflon capvial (Thermo Fisher Scientific) with 5 g of NaCl and sealed with a silicone/PTFE septum and a magnetic cap for continuous agitation and heating.Headspace volatiles were extracted by exposing a 75-μm carboxen-polydimethylsiloxane SPME fiber (Supelco,USA) to the vial headspace.The fiber was then inserted into an ISQ GC-MS (Thermo Scientific instruments,USA) injection port and the volatiles were desorbed and performed on an HP-INNOWAX column with helium as the carrier gas at a constant flow.[Results] At different stages of fruit development,the relative contents and types of volatile components changed greatly.A total of 16 volatile components with relative content higher than 1% in all three development stages were detected,including 2 aldehydes,9 esters,4 alcohols and 1 acid.In green fruit,the main volatile components were trans-2-hexenal,caproaldehyde,leaf alcohol and hexyl alcohol,and the relative content of the four components reached 82.61% with trans-2-hexenal accounting for 48.09%.In degreening fruit,the main volatile components included caprylic acid methyl ester,prenyl acetate,methyl decanoate,4-penten-1-yl acetate,cineole,and α-terpineol and linalool.These 7 compounds occupied 68.85% and caprylic acid methyl ester was most abundant (35.86%).Esters increased obviously in degreening fruit compared with green fruit.In ripe fruit,the relative contents of 9 volatile components were higher than 1%.They were prenyl acetate,ethyl caprylate,caprylic acid methyl ester,4-penten-1-yl acetate,cineole,ethyl caproate,octanoic acid,α-terpineol and ethyl caprate.Their relative content was 42.76% and prenyl acetate was the highest one (9.40%),followed by ethyl caprylate (9.29%).In ripe fruit,the relative content of prenyl acetate and caprylic acid

  14. 残次裂枣枣酒发酵菌相变化及工艺比较分析%Study on Variation of Microbial Community and Comparison of Two Fermentation Technologies in Making Wine by Defective Jujube

    Institute of Scientific and Technical Information of China (English)

    潘凯旋; 甘峰; 李志西; 王晨; 张俊娜

    2012-01-01

    bacteria and acetic acid bacteria. The contents of alcohol and Vc in the wine produced by direct fermentation technique were 8. 9% and 45. 8 jug/g. And the contents of them in the wine made by the second technology were 7.8% and 47. 7 jug/g. The contents of polyphenol, ethyl acetate, ethyl lac-tate, and ethyl caproate in the wine produced by direct fermentation technology were higher and the content of fusel oil was lower than that produced by the other technique. The contents of methanol in the wine produced by both the fermentation technologies were lower than 0. 4 g/L which was the max-imal value regulated by Chinese National Standard. So, the property of wine produced by direct fermentation technique was better than that produced by another technique.