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Sample records for niger republic mineral

  1. Uranium deposits in the Republic of Niger

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-03-01

    Niger is located at the southern edge of the Sahara desert in north-central Africa. The country covers a territory of 1,267,000 square kilometers (489,191 square miles), or about three times the size of California, with a population exceeding 7.5 million people. In 1989, Niger abandoned 16 years of military rule and is now on the way to a democratic system; the first multiparty elections are schedules for 1992. Mining industries are the primary base for Niger`s economy. Uranium is the leading export commodity, with revenues accounting for about one-third of Niger`s export earnings. Other mineral products include coal, tin, and small amounts of gold.

  2. Amino acid, mineral and fatty acid content of pumpkin seeds (Cucurbita spp) and Cyperus esculentus nuts in the Republic of Niger.

    Science.gov (United States)

    Glew, R H; Glew, R S; Chuang, L-T; Huang, Y-S; Millson, M; Constans, D; Vanderjagt, D J

    2006-06-01

    Dried seeds and nuts are widely consumed by indigenous populations of the western Sahel, especially those who inhabit rural areas. In light of the need for quantitative information regarding the content of particular nutrients in these plant foods, we collected dried pumpkin (Cucurbita spp) seeds and nuts of Cyperus esculentus in the Republic of Niger and analyzed them for their content of essential amino acids, minerals and trace elements, and fatty acids. On a dry weight basis, pumpkin seed contained 58.8% protein and 29.8% fat. However, the lysine score of the protein was only 65% relative to the FAO/WHO protein standard. The pumpkin seed contained useful amounts of linoleic (92 microg/g dry weight) and the following elements (on a microg per g dry weight basis): potassium (5,790), magnesium (5,690), manganese (49.3), zinc (113), selenium (1.29), copper (15.4), chromium (2.84), and molybdenum (0.81), but low amounts of calcium and iron. Except for potassium (5,573 microg/g dry weight) and chromium (2.88 microg/g dry weight), the C. esculentis nuts contained much less of these same nutrients compared to pumpkin seeds. In conclusion, pumpkin seeds represent a useful source of many nutrients essential to humans. The data in this report should of practical value to public health officials in rural areas of sub-Saharan Africa.

  3. Balneological Evaluation of the Tafadek Spring, Agadez Region, Niger Republic

    Science.gov (United States)

    Nghargbu, K.; Latour, T.; Ponikowska, I.; Kurowska, E.

    2012-04-01

    West Africa, particularly Niger Republic is home to thousands of tourists annually. The vast Saharan desert and it's numerous oases in the northern parts of the Republic are a hot attraction on their own. However, in a recent survey of medicinal springs within the West African sub-region, the only hot spring in this country known locally for its therapeutic egress was analyzed. Located about 160km West of Agadez, the "Tafadek" spring with a yield of over 5l/s and temperature of about 50oC, rich in fluoride and silica is a specific water with capacity for application in balneotherapy for the treatment of orthopaedic, rheumatological, neurological, urinary tract infections, and osteoporosis. If the Tafadek spring is developed into a modern health resort promoting balneotherapy, health (balnear) tourism which is non-existent in Niger Republic today could kick start a new dawn in the health/economic development of the nation and the sub-region at large. Keywords: West Africa, Nigeria, Balneotherapy, Health tourism, Spring

  4. Ecology of urban malaria vectors in Niamey, Republic of Niger.

    Science.gov (United States)

    Labbo, Rabiou; Fandeur, Thierry; Jeanne, Isabelle; Czeher, Cyril; Williams, Earle; Arzika, Ibrahim; Soumana, Amadou; Lazoumar, Ramatoulaye; Duchemin, Jean-Bernard

    2016-06-08

    Urbanization in African cities has major impact on malaria risk. Niamey, the capital of the Republic of Niger, is situated in the West African Sahel zone. The short rainy season and human activities linked with the Niger River influence mosquito abundance. This study aimed at deciphering the factors of distribution of urban malaria vectors in Niamey. The distribution of mosquito aquatic stages was investigated monthly from December 2002 to November 2003, at up to 84 breeding sites, throughout Niamey. An exploratory analysis of association between mosquito abundance and environmental factors was performed by a Principal Component Analysis and confirmed by Kruskall-Wallis non-parametric test. To assess the relative importance of significant factors, models were built for Anopheles and Culicinae. In a second capture session, adult mosquitoes were collected weekly with pyrethrum sprays and CDC light-traps from June 2008 to June 2009 in two differentiated urban areas chosen after the study's first step. Members of the Anopheles gambiae complex were genotyped and Anopheles females were tested for the presence of Plasmodium falciparum circumsporozoite antigens using ELISA. In 2003, 29 % of 8420 mosquitoes collected as aquatic stages were Anopheles. They were significantly more likely to be found upstream, relatively close to the river and highly productive in ponds. These factors remained significant in regression and generalized linear models. The Culicinae were found significantly more likely close to the river, and in the main temporary affluent stream. In 2009, Anopheles specimens, including Anopheles gambiae s.l. (95 %), but also Anopheles funestus (0.6 %) accounted for 18 % of the adult mosquito fauna, with a large difference between the two sampled zones. Three members of the An. gambiae complex were found: Anopheles arabiensis, Anopheles coluzzii, and An. gambiae. Nineteen (1.3 %) out of 1467 females tested for P. falciparum antigen were found positive. The

  5. Niger

    DEFF Research Database (Denmark)

    Hahonou, Eric Komlavi

    2015-01-01

    The chapter provides knowledge about the role of non-state actors in security provision in Niger. It argues that it is of upmost importance to dig into the causes of ongoing armed conflicts and volatile situations. It points out the long-term decline of public service provision (including the rol...... played by police force in protection rackets) and the growing gap between ruling elites and ordinary citizens. These developments have paved the way for the rise of alternative security providers, including Islamic reformist movements.......The chapter provides knowledge about the role of non-state actors in security provision in Niger. It argues that it is of upmost importance to dig into the causes of ongoing armed conflicts and volatile situations. It points out the long-term decline of public service provision (including the role...

  6. [Formation of Aspergillus niger-mineral aggregation and characterization of polysaccharide from aggregation].

    Science.gov (United States)

    Hu, Jie; Lian, Bin; Yu, Jianping; Hu, Xing

    2011-06-01

    In order to understand the weathering on potassium-bearing mineral by Aspergillus niger, we studied the formation of A. niger-mineral aggregation and polysaccharide in the revolving and fermenting mode and their role in the process of weathering on potassium-bearing mineral. We used four different media to study the morphology of A. niger-mineral aggregation; ultraviolet-visible spectrum (UV-Vis) , fourier transform infrared spectrum (IR), gas chromatography (GC), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) were combined to research the changes of polysaccharide and their significances in the micro-environment forming fungal-mineral aggregation. A. niger myclia intertwined, adsorbed and bonded mineral powder to form aggregation by the assistance of polysaccharide and other metabolites. After formation of the aggregation, the concentration and structure of polysaccharide were changed significantly. The changes of polysaccharide would enhance the adsorption on minerals, chelation on metal ions and adsorption on water molecules, which provided a favorable micro-environment for the fungal using mineral nutrients effectively.

  7. Prevalence of peste des petits ruminants in the arid zone in the Republic of Niger

    Directory of Open Access Journals (Sweden)

    Souaibou Farougou

    2013-03-01

    Full Text Available The study aimed to determine the prevalence of peste des petits ruminants in the arid zone (Niamey, Tillabéry and Tahoua of the Republic of Niger. A serological survey was conducted and 519 serum samples were collected from 253 unvaccinated sheep and 266 unvaccinated goats. The sample included 340 female animals (168 sheep and 172 goats and 160 kids and lambs (78 lambs and 82 kids. A competitive enzyme-linked immunosorbent assay yielded an overall seroprevalence of 45.0%. The prevalence in sheep was 42.0% compared with 47.9% in goats. The seroprevalence observed amongst small ruminants in Tahoua (49.8% and Tillabéry (46.6% was significantly higher (p = 0.001 than that observed in animals from Niamey (25.1%. It was also higher (p = 0.04 in sheep younger than two years (51.8% than in adults (37.6%. Conversely, the seroprevalence showed no significant difference between male animals (35.8% in sheep; 50.1% in goats and female animals (45.1% in sheep; 46.4% in goats. The prevalence of the disease observed amongst the sheep and goat populations confirms the continued danger of this disease in the areas studied. It is therefore necessary to develop strategies such as improving livestock services, providing effective vaccines and implementing a vaccination programme for an effective control of the disease in sub-Saharan Africa.

  8. CITRIC ACID PRODUCTION BY WILD AND UV - TREATED STRAINS OF ASPERGILLUS NIGER ON TWO DIFFERENT MINERAL SALT MEDIA

    OpenAIRE

    Valentine Enyinna Anyanwu; Phillip O. Okerentugba

    2013-01-01

    Microbial production of citric acid by a novel Aspergillus niger EE-12 and its UV – treated strain (UV-1) were carried out in shake flask cultures using mineral salt media containing sucrose or fructose as the carbon and energy sources. The highest citric acid concentration (36.1g/l) was obtained with the UV – treated strain UV-1 after 144 hours in medium containing sucrose and this was significantly higher (p

  9. Analysis of nutritional components of eight famine foods of the Republic of Niger.

    Science.gov (United States)

    Sena, L P; Vanderjagt, D J; Rivera, C; Tsin, A T; Muhamadu, I; Mahamadou, O; Millson, M; Pastuszyn, A; Glew, R H

    1998-01-01

    In the western Sahel, indigenous plants become important staples when cereal harvests are inadequate to support populations inhabiting that region of Africa. The purpose of this study was to assess the nutrient content of several of these edible wild plants. The leaves of the following seven plant foods were analyzed: Ziziphus mauritiana, Cerathotheca sesamoides, Moringa oleifera, Leptadenia hastata, Hibiscus sabdarifa, Amaranthus viridis, and Adansonia digitata. The fatty acid, vitamin E, carotenoid, selected mineral and amino acid contents of these plant foods were determined. These same analyses were performed on the fruit of the Adanisonia digitata. In quantitative and qualitative terms, Amaranthus viridis was found to be an excellent source of protein. Its amino acid composition compared favorably to that of a World Health Organization (WHO) protein standard. It also contained considerable amounts of the two fatty acids that are essential in humans (linoleic and alpha-linolenic) and a number of minerals including iron, magnesium. calcium and zinc. The leaves of Hibiscus sabdarifa contained an appreciable quantity of protein the composition of which was comparable to the WHO standard. The mineral content of the leaves of this plant was also exceptionally high; noteworthy was its high zinc content. H. sabdarifa also contained significant quantities of the two essential fatty acids. Ziziphus mauritiana was an excellent source of the essential fatty acid linoleic acid and several of the metals including iron, calcium, magnesium and zinc. Its content of other essential nutrients, however, was rather low. In general, Adansonia digitata leaves were nutritionally superior to the fruit of the tree; however, the fruit did contain useful quantities of potassium, phosphorus, zinc and alpha-linolenic acid. The Leptadenia hastata leaves were an especially good source of lutein and beta-carotene. These data should be useful to the people who inhabit the western Sahel in

  10. Mineral values of selected plant foods common to southern Burkina Faso and to Niamey, Niger, west Africa.

    Science.gov (United States)

    Smith, G C; Clegg, M S; Keen, C L; Grivetti, L E

    1996-01-01

    Wild and cultivated fruits, leaves, nuts, seeds, spices and vegetables from southern Burkina Faso and Niamey, Niger, were analysed for their copper, iron, magnesium, manganese and zinc concentrations and compared to imported, exotic reference foods found within the study area. The species analysed covered a broad spectrum of local diet; 33 were wild and 16 were cultivated. The edible wild plants were often the highest in mineral concentrations. Five species analysed, exhibited consistently high mineral values, specifically, Adansonia digitata, Boerhavia diffusa, Cerathoteca sesamoides, Sclerocarya birrea and Xylopia sp. The latter was particularly high in zinc, an observation which suggests that there may be a solid rationale for local traditions which recommended its consumption during pregnancy and lactation. Respondents indicated that during times of drought, wild plants were not consumed in the volume they once were, due to changes of infrastructure and in famine relief programmes.

  11. ASPERGILLUS NIGER ASPERGILLUS NIGER

    African Journals Online (AJOL)

    eobe

    activity of Aspergillus niger for the purpose of improved citric acid production from cocoyam starch. ... these conditions, the maximum citric acid concentration was obtained as 108 g/L. ..... Citric Acid in Milk with an Improved Pyridine-Acetic.

  12. Insoluble Content, Ionic Composition, Density, and X-Ray Diffraction Spectra of 6 Evaporites from Niger Republic

    Directory of Open Access Journals (Sweden)

    Hassidou Saidou

    2015-01-01

    Full Text Available Some physicochemical (insoluble content, ionic composition, density, and X-ray diffraction spectra characteristics of Nigerien evaporites were investigated in this study. The results obtained showed that trona is the main mineral contained in Agadez, Dirkou, Niamey, and Zinder evaporites while thenardite and halite constitute the major minerals in Bilma and Tabalak evaporites, respectively. In addition, all evaporites samples investigated revealed the presence of quartz and halite. Other interesting minerals (calcite, gypsum, sylvite, aphthitalite, nahcolite, illite, burkeite, kaolinite, griceite, and talc were also detected. The use of Agadez, Dirkou, Niamey, and Zinder evaporites as catalyst to accelerate cowpea cooking is due to bicarbonates ions present in trona. Bilma and Tabalak evaporites employed in animal feeding are due to the halite contained in a significant quantity.

  13. Inadequate status of iodine nutrition among pregnant women residing in three districts of Niamey, the Niger Republic's capital.

    Science.gov (United States)

    Sadou, Hassimi; Seyfoulaye, Amina; Malam Alma, Mousbahou; Daouda, Hamani

    2014-10-01

    Universal dietary salt iodisation (UDSI) programme was implemented in Niger in 1996. However, since 2000, there has been a slowdown in progress against iodine deficiency. The aim of our study was to assess the iodine status among pregnant women in a context where national controls are not effective at ensuring universal availability of adequately iodised salt. This is mainly to assess the impact of the slowdown in the fight against iodine deficiency in this vulnerable group. The study was centred on 240 healthy pregnant women volunteers recruited in three districts primary health centres. A control group of 60 non-pregnant, non-lactating healthy women was also studied and compared. Median urinary iodine concentration (UIC) of all pregnant women was 119 μg L(-1) , and 61.67% had UIC below 150 μg L(-1) . Median UIC for the first, second and third trimester were 144, 108 and 92 μg L(-1) , respectively. The percentage of pregnant women with UIC below 150 μg L(-1) increased from 52% in the first trimester to 66% in the third trimester. The median UIC of the control group was 166 μg L(-1) , and 28.33% had UIC below 100 μg L(-1) . No significant relationship was found between nutritional iodine status and provenance, age and parity. However, significant relationship was found between iodine status and stage of pregnancy, gestational age and educational level (P nutrition status thus observed was inadequate in 61.67% of all the pregnant women. It is therefore urgent to revitalise implementation of the UDSI programme, and in the short term to consider iodine supplementation for pregnant women.

  14. Porphyry copper assessment of East and Southeast Asia: Philippines, Taiwan (Republic of China), Republic of Korea (South Korea), and Japan: Chapter P in Global mineral resource assessment

    Science.gov (United States)

    Hammarstrom, Jane M.; Bookstrom, Arthur A.; Demarr, Michael W.; Dicken, Connie L.; Ludington, Stephen; Robinson,, Gilpin R.; Zientek, Michael L.

    2014-01-01

    The U.S. Geological Survey collaborated with member countries of the Coordinating Committee for Geoscience Programmes in East and Southeast Asia (CCOP) on an assessment of the porphyry copper resources of East and Southeast Asia as part of a global mineral resource assessment. The assessment covers the Philippines in Southeast Asia, and the Republic of Korea (South Korea), Taiwan (Province of China), and Japan in East Asia. The Philippines host world class porphyry copper deposits, such as the Tampakan and Atlas deposits. No porphyry copper deposits have been discovered in the Republic of Korea (South Korea), Taiwan (Province of China), or Japan.

  15. Role of different additives and metallic micro minerals on the enhanced citric acid production by Aspergillus niger MNNG-115 using different carbohydrate materials.

    Science.gov (United States)

    Ali, Sikander; Haq, Ikram-ul

    2005-01-01

    The present investigation deals with the promotry effect of different additives and metallic micro minerals on citric acid production by Aspergillus niger MNNG-115 using different carbohydrate materials. For this, sugar cane bagasse was fortified with sucrose salt medium. Ethanol and coconut oil at 3.0% (v/w) level increased citric acid productivity. Fluoroacetate at a concentration of 1.0 mg/ml bagasse enhanced the yield of citric acid significantly. However, the addition of ethanol and fluoroacetate after 6 h of growth gave the maximum conversion of available sugar to citric acid. In another study, influence of some metallic micro-minerals viz. copper sulphate, molybdenum sulphate, zinc sulphate and cobalt sulphate on microbial synthesis of citric acid using molasses medium was also carried out. It was found that copper sulphate and molybdenum sulphate remarkably enhanced the production of citric acid while zinc sulphate was not so effective. However, cobalt sulphate was the least effective for microbial biosynthesis of citric acid under the same experimental conditions. In case of CuSO(4), the strain of Aspergillus niger MNNG-115 showed enhanced citric productivity with experimental (9.80%) over the control (7.54%). In addition, the specific productivity of the culture at 30 ppm CuSO(4) (Q(p) = 0.012a g/g cells/h) was several folds higher than other all other concentrations. All kinetic parameters including yield coefficients and volumetric rates revealed the hyper productivity of citric acid by CuSO(4) using blackstrap molasses as the basal carbon source.

  16. Stabilizing Niger

    DEFF Research Database (Denmark)

    Hahonou, Eric Komlavi

    international intervention in Niger. Their main objective is to secure their own strategic, economic and political interests by strengthening the Nigerien authorities through direct intervention and capacity building activities. For western states reinforcing state security institutions and stabilizing elite...

  17. Mineral waters of the Pannonian basin spas in the Republic of Serbia

    Directory of Open Access Journals (Sweden)

    Klimo Atila

    2011-01-01

    Full Text Available Introduction. The fact itself that thermo-mineral waters and mud have healing effects has always attracted attention throughout the history to exploit, explore and study their benefit on the human body. Modern lifestyle and the speed of life endanger man’s psycho-physical health. This is why people more often return to old time proven values, the nature and natural health resorts. Objective. To establish hydro-geological conditions for the formation of mineral water and to summarize their balneological characteristics in spas, i.e., in rehabilitation centres of the Pannonian basin of the Republic of Serbia, where underground waters are still actively exploited for balneotherapy. Methods. By retrospective descriptive analysis, a recapitulation of hydro-geological conditions for the formation of mineral waters was made and their balneological characteristics were established in eight spas of the Pannonian basin. Results. The healing spas of the Pannonian basin are predominated by HCO3 (2.9 g/l - 4.6% milival, iodic (up to 6.5 mg/l, slightly alkaline (pH up to 8.1 thermal-mineral water (temperature up to 72°C, bounty to 36.6 l/s with a significant content of Br (up to 8.1 mg/l, Fe (to 6.0 mg/l, metaboron (up to 60 mg/l and metasilicon acid (up to 95 mg/l. They are used for external application, bathing and showering. Conclusion. Once the Pannonian Sea (the Paratethys, today a wide plain terrain is a tectonic depression of the lower Pannonian pont age with compact type aquifers. In the geological column of sedimentary rocks a large underground aquifer was formed with free water of high mineralization, high temperature and geothermal properties above the average in relation to the European hydrogeological standards. Therefore, the Pannonian basin can be rightly called a thermal valley with the predominance of sodium hydro-carbonate (alkaline iodine healing water of enviable abundance and reserves.

  18. Lithium content in potable water, surface water, ground water, and mineral water on the territory of Republic of Macedonia

    OpenAIRE

    Vesna Kostik; Biljana Bauer; Zoran Kavrakovski

    2014-01-01

    The aim of this study was to determine lithium concentration in potable water, surface water, ground, and mineral water on the territory of the Republic of Macedonia. Water samples were collected from water bodies such as multiple public water supply systems located in 13 cities, wells boreholes located in 12 areas, lakes and rivers located in three different areas. Determination of lithium concentration in potable water, surface water was performed by the technique of inductively coupl...

  19. Agricolaite, a new mineral of uranium from Jáchymov, Czech Republic

    Science.gov (United States)

    Skála, Roman; Ondruš, Petr; Veselovský, František; Císařová, Ivana; Hloušek, Jan

    2011-11-01

    The new mineral agricolaite, a potassium uranyl carbonate with ideal formula K4(UO2)(CO3)3, occurs in vugs of ankerite gangue in gneisses in the abandoned Giftkiesstollen adit at Jáchymov, Czech Republic. The name is after Georgius Agricola (1494-1555), German scholar and scientist. Agricolaite occurs as isolated equant irregular translucent grains to 0.3 mm with yellow color, pale yellow streak, and vitreous luster. It is brittle with uneven fracture and displays neither cleavage nor parting. Agricolaite is non-fluorescent. Mohs hardness is ~4. It is associated with aragonite, brochantite, posnjakite, malachite, rutherfordine, and "pseudo-voglite". Experimental density is higher than 3.3 g.cm-3, Dcalc is 3.531 g. cm-3. The mineral is monoclinic, space group C2/ c, with a 10.2380(2), b 9.1930(2), c 12.2110(3) Å, β 95.108(2)°, V 1144.71(4) Å3, Z = 4. The strongest lines in the powder X-ray diffraction pattern are d( I)( hkl): 6.061(55)(002), 5.087(57)(200), 3.740(100)(202), 3.393(43)(113), 2.281(52)(402). Average composition based on ten electron microprobe analyses corresponds to (in wt.%) UO3 48.53, K2O 31.49, CO2(calc) 22.04 which gives the empirical formula K3.98(UO2)1.01(CO3)3.00. The crystal structure was solved from single-crystal X-ray diffraction data and refined to R 1 = 0.0184 on the basis of the 1,308 unique reflections with F o > 4 σF o. The structure of agricolaite is identical to that of synthetic K4(UO2)(CO3)3 and consists of separate UO2(CO3)3 groups organized into layers parallel to (100) and two crystallographically non-equivalent sites occupied by K+ cations. Both the mineral and its name were approved by the IMA-CNMNC.

  20. Plumbotectonic aspects of polymetallic vein mineralization in Paleozoic sediments and Proterozoic basement of Moravia (Czech Republic)

    Science.gov (United States)

    Slobodník, Marek; Jacher-Śliwczyńska, Katarzyna; Taylor, Matthew C.; Schneider, Jens; Dolníček, Zdeněk

    2008-02-01

    A regional isotopic study of Pb and S in hydrothermal galenas and U-Pb and S in potential source rocks was carried out for part of Moravia, Czech Republic. Two major generations of veins, (syn-) Variscan and post-Variscan, are defined based on the Pb-isotope system together with structural constraints (local structures and regional trends). The Pb-isotopic compositions of galena plot in two distinct populations with outliers in 206Pb/204Pb-207Pb/204Pb space. Galena from veins hosted in greywackes provides a cluster with the lowest Pb-Pb ratios: 206Pb/204Pb = 18.15-18.27, 207Pb/204Pb = 15.59-15.61, 208Pb/204Pb = 38.11-38.23. Those hosted in both limestones and greywackes provide the second cluster: 206Pb/204Pb = 18.37-18.44, 207Pb/204Pb = 15.60-15.63, 208Pb/204Pb = 38.14-38.32. These clusters suggest model Pb ages as Early Carboniferous and Triassic-Jurassic, the latter associated with MVT-like deposits. Two samples from veins hosted in Proterozoic rocks lie outside the two clusters: in metagranitoid (206Pb/204Pb = 18.55, 207Pb/204Pb = 15.64, 208Pb/204Pb = 38.29) and in orthogneiss (206Pb/204Pb = 18.79, 207Pb/204Pb = 15.73, 208Pb/204Pb = 38.54). The results from these two samples suggest an interaction of mineralizing fluids with the radiogenic Pb-rich source (basement?). The values of δ34S suggest the Paleozoic host rocks (mostly -6.7 to +5.2‰ CDT) as the source of S for hydrothermal sulfides (mostly -4.8 to +2.5‰ CDT). U-Pb data and Pb isotope evolutionary curves indicate that Late Devonian and Early Carboniferous sediments, especially siliciclastics, are the general dominant contributor of Pb for galena mineralization developed in sedimentary rocks. Plumbotectonic mixing occurred, it is deduced, only between the lower and the upper crust (the latter involving Proterozoic basement containing heterogeneous radiogenic Pb), without any significant input from the mantle. It is concluded that in the Moravo-Silesian and Rhenohercynian zones (including proximal

  1. Geochemical and isotopic investigations on the thermal and mineral underground waters from the Republic of Moldova

    Science.gov (United States)

    Nisi, Barbara; Bogdevich, Oleg; Vaselli, Orlando; Nicoara, Igor; Tassi, Franco; Culighin, Elena; Mogorici, Cristina; Jeleapov, Victor; Mussi, Mario

    2017-04-01

    Republic of Moldova (RM) has a large spectrum of underground mineral waters (16 reservoirs) of eight principal aquifers, most of which affected by contaminants originated by natural sources and anthropogenic activities. Inorganic natural tracers and stable isotopes are useful tools to fingerprint the water source and solutes, respectively. The aim of this investigation was to determine the geochemical and isotopic features of the most important thermo- and mineral waters from RM to trace their flow pathways and evaluate the presence of deep fluid sources discharging from fault systems, developed in response to the structural setting of the area. To the best of our knowledge, no systematic geochemical investigations were previously carried out in this area. RM has an area of 33,840 km2 and lies within the East European Precambrian Platform, two structural and/or stratigraphic layers, which are distinguishable in basement and sedimentary cover in the northern and central part of country. The basement rocks include granites, gneisses and gabbros. The sedimentary cover, overlying the crystalline basement, is almost undeformed and consists of Upper Proterozoic, Mesozoic and Cenozoic rocks. The geological structure is like a matrix formed from different layers of rocks consisting of permeable and impermeable strata. The deep aquifers are situated down to 1,000 m depth from the bottom to the top: Vendian (Ediocariam) and crystalline basement rocks, Silurian crystalline limestone, Cretaceous limestone, Baden-Sarmatian limestone and clay-sand deposits, middle Sarmatian limestone and clay-sand layers. Other younger aquifers were not investigated. In this framework, 54 samples from the most important underground reservoirs of RM were collected and analyzed for major, trace species and dissolved gases. An inventory of isotopic (18O/16O and 2H/1H ratios in water and 13C/12C in dissolved CO2) features (including tritium units in selected samples) was also provided. By a

  2. Stabilizing Niger

    DEFF Research Database (Denmark)

    Hahonou, Eric Komlavi

    international intervention in Niger. Their main objective is to secure their own strategic, economic and political interests by strengthening the Nigerien authorities through direct intervention and capacity building activities. For western states reinforcing state security institutions and stabilizing elite...... rule constitute the only realistic path to defend their own interests. The report suggests that international support of Nigerien security forces could be counter-productive for the re-establishment of state authority and legitimacy in the long-term. Brutal repression and violation of human rights...

  3. Formation of Aspergillus niger-mineral aggregation and characterization of polysaccharide from aggregation%黑曲霉-矿物聚集体的形成及其分泌的多糖特性

    Institute of Scientific and Technical Information of China (English)

    胡婕; 连宾; 郁建平; 胡星

    2011-01-01

    [Objective]In order to understand the weathering on potassium-bearing mineral by Aspergillus niger, we studied the formation of A.niger-mineral aggregation and polysaccharide in the revolving and fermenting mode and their role in the process of weathering on potassium-bearing mineral.[Methods]We used four different media to study the morphology of A.niger-mineral aggregation; ultraviolet-visible spectrum ( UV-Vis ) , fourier transform infrared spectrum (IR), gas chromatography( GC) , scanning electron microscopy ( SEM ) and energy dispersive spectrometer ( EDS ) were combined to research the changes of polysaccharide and their significances in the micro-environment forming fungal-mineral aggregation.[Results]A, niger myclia intertwined, adsorbed and bonded mineral powder to form aggregation by the assistance of polysaccharide and other metabolites.After formation of the aggregation, the concentration and structure of polysaccharide were changed significantly.[Conclusion]The changes of polysaccharide would enhance the adsorption on minerals , chelation on metal ions and adsorption on water molecules, which provided a favorable micro-environment for the fungal using mineral nutrients effectively.%[目的]为深入理解黑曲霉(Aspergillus niger)对含钾矿粉的风化作用,研究在旋转发酵方式下形成的黑曲霉-矿物聚集体及其多糖,并分析它们在含钾矿粉风化过程中的作用.[方法]采用不同组合培养基,研究黑曲霉-矿物聚集体的形成和形貌;联合紫外-可见分光光谱(UV-Vis)、傅立叶变换红外光谱(FT-IR)、气相色谱(GC)、电子扫描显微镜(SEM)、x射线能谱仪(EDS)等分析手段研究黑曲霉-矿物聚集体形成前后微环境中多糖的变化以及这种改变对风化产生的意义.[结果]黑曲霉菌丝与矿粉在多糖等代谢产物帮助下,通过相互缠绕、吸附、粘合等作用形成黑曲霉-矿物聚集体,聚集体形成前后多糖浓度和多糖结构均发生显著

  4. Lithium content in potable water, surface water, ground water, and mineral water on the territory of Republic of Macedonia

    Directory of Open Access Journals (Sweden)

    Vesna Kostik

    2014-07-01

    Full Text Available The aim of this study was to determine lithium concentration in potable water, surface water, ground, and mineral water on the territory of the Republic of Macedonia. Water samples were collected from water bodies such as multiple public water supply systems located in 13 cities, wells boreholes located in 12 areas, lakes and rivers located in three different areas. Determination of lithium concentration in potable water, surface water was performed by the technique of inductively coupled plasma-mass spectrometry, while in ground water samples from wells boreholes and mineral waters with the technique of ion chromatography. The research shows that lithium concentration in potable water ranging from 0.1 to 5.2 μg/L; in surface water from 0.5 to 15.0 μg/L; ground water from wells boreholes from 16.0 to 49.1 μg/L and mineral water from 125.2 to 484.9 μg/L. Obtained values are in accordance with the relevant international values for the lithium content in water.

  5. Conflict minerals from the Democratic Republic of the Congo—Gold supply chain

    Science.gov (United States)

    George, Micheal W.

    2015-11-10

    The U.S. Geological Survey (USGS) analyzes mineral and metal supply chains to identify and describe major components of material flows from ore extraction, through intermediate forms, to a final product. Supply chain analyses may be used to identify risks to the United States associated with the supply of critical and strategic minerals and metals and to provide greater supply chain transparency so that policymakers have the fact-based information needed to formulate public policy. This fact sheet focuses on the gold supply chain.

  6. [The relationship between the parameters of mineral density of bone tissue and somatotype in women residing in the Republic of Karelia].

    Science.gov (United States)

    Pashkova, I G; Gaivoronskiy, I V; Aleksina, L A; Kornev, M A

    2014-01-01

    Comprehensive anthropometric and densitometric study using the dual x-ray absorptiometry was conducted to determine the relationship between the mineral density of bone tissue and somatotype in 360 women aged 20 to 87 years, permanently residing in the Republic of Karelia. Significant direct correlation was detected between the somatotype and the amount of mineral substances in the vertebrae, bone mineral density and the area of the lumbar vertebrae. Bone mineral density level of the lumbar vertebrae was higher in women with europlastic and athletic somatotypes, which were characterized by high values of body mass and length, body muscle and fat mass. Low values of bone mineral density of vertebrae were identified in women belonging to subathletic, mesoplastic and stenoplastic somatotypes. The risk of developing osteopenia and osteoporosis is increased in women with low body muscle mass.

  7. Conflict minerals from the Democratic Republic of the Congo: global tungsten processing plants, a critical part of the tungsten supply chain

    Science.gov (United States)

    Bermúdez-Lugo, Omayra

    2014-01-01

    The U.S. Geological Survey (USGS) analyzes supply chains to identify and define major components of mineral and material flows from ore extraction, through intermediate forms, to a final product. Two major reasons necessitate these analyses: (1) to identify risks associated with the supply of critical and strategic minerals to the United States and (2) to provide greater supply chain transparency so that policymakers have the information necessary to ensure domestic legislation compliance. This fact sheet focuses on the latter. The USGS National Minerals Information Center has been asked by governmental and non-governmental organizations to provide information on tin, tantalum, tungsten, and gold (collectively known as “3TG minerals”) processing facilities worldwide in response to U.S. legislation aimed at removing the link between the trade in these minerals and civil unrest in the Democratic Republic of the Congo. Post beneficiation processing plants (smelters and refineries) of 3TG mineral ores and concentrates were identified by company and industry association representatives as being the link in the 3TG mineral supply chain through which these minerals can be traced to their source of origin (mine); determining the point of origin is critical to establishing a transparent conflict mineral supply chain. This fact sheet, the first in a series of 3TG mineral fact sheets, focuses on the tungsten supply chain by listing plants that consume tungsten concentrates to produce ammonium paratungstate and ferrotungsten worldwide.

  8. Fibrous Platinum-Group Minerals in “Floating Chromitites” from the Loma Larga Ni-Laterite Deposit, Dominican Republic

    Directory of Open Access Journals (Sweden)

    Thomas Aiglsperger

    2016-11-01

    Full Text Available This contribution reports on the observation of enigmatic fibrous platinum-group minerals (PGM found within a chromitite body included in limonite (“floating chromitite” from Ni-laterites in the Dominican Republic. Fibrous PGM have a Ru-Os-Ir-Fe dominated composition and are characterized by fibrous textures explained by grain-forming fibers which are significantly longer (1–5 µm than they are wide (~100 nm. Back-scattered electron (BSE images suggest that these nanofibers are platinum-group elements (PGE-bearing and form <5 µm thick layers of bundles which are oriented orthogonal to grains’ surfaces. Trace amounts of Si are most likely associated with PGE-bearing nanofibers. One characteristic fibrous PGM was studied in detail: XRD analyses point to ruthenian hexaferrum. However, the unpolished fibrous PGM shows numerous complex textures on its surface which are suggestive for neoformation processes: (i features suggesting growth of PGE-bearing nanofibers; (ii occurrence of PGM nanoparticles within film material (biofilm? associated with PGE-bearing nanofibers; (iii a Si-rich and crater-like texture hosting PGM nanoparticles and an Ir-rich accumulation of irregular shape; (iv complex PGM nanoparticles with ragged morphologies, resembling sponge spicules and (v oval forms (<1 µm in diameter with included PGM nanoparticles, similar to those observed in experiments with PGE-reducing bacteria. Fibrous PGM found in the limonite may have formed due to supergene (bio-weathering of fibrous Mg-silicates which were incorporated into desulphurized laurite during stages of serpentinization.

  9. Size distribution, shape, and composition of mineral dust aerosols collected during the African Monsoon Multidisciplinary Analysis Special Observation Period 0: Dust and Biomass-Burning Experiment field campaign in Niger, January 2006

    Science.gov (United States)

    Chou, CéDric; Formenti, Paola; Maille, Michel; Ausset, Patrick; Helas, Günter; Harrison, Mark; Osborne, Simon

    2008-12-01

    Dust samples were collected onboard the UK community BAe-146 research aircraft of the Facility for Airborne Atmospheric Measurements (FAAM) operated over Niger during the winter Special Observation Period of the African Monsoon Multidisciplinary Analysis project (AMMA SOP0/DABEX). Particle size, morphology, and composition were assessed using single-particle analysis by analytical scanning and transmission electron microscopy. The aerosol was found to be composed of externally mixed mineral dust and biomass burning particles. Mineral dust consists mainly of aluminosilicates in the form of illite and kaolinite and quartz, accounting for up to 80% of the aerosol number. Fe-rich particles (iron oxides) represented 4% of the particle number in the submicron fraction. Diatoms were found on all the samples, suggesting that emissions from the Bodélé depression were also contributing to the aerosol load. Satellite images confirm that the Bodélé source was active during the period of investigation. Biomass burning aerosols accounted for about 15% of the particle number of 0.1-0.6 μm diameter and were composed almost exclusively of particles containing potassium and sulfur. Soot particles were very rare. The aspect ratio AR is a measure of particle elongation. The upper limit of the AR value distribution is 5 and the median is 1.7, which suggests that mineral dust particles could be described as ellipsoids whose major axis never exceeds 1.9 × Dp (the spherical geometric diameter). This is consistent with other published values for mineral dust, including the recent Aerosol Robotic Network retrieval results of Dubovik et al. (2006).

  10. Conflict minerals from the Democratic Republic of the Congo: global tantalum processing plants, a critical part of the tantalum supply chain

    Science.gov (United States)

    Papp, John F.

    2014-01-01

    The U.S. Geological Survey (USGS) analyzes mineral and metal supply chains to identify and describe major components of mineral and metal material flows from ore extraction, through intermediate forms, to a final product. Supply chain analyses may be used (1) to identify risks to the United States associated with the supply of critical and strategic minerals and metals and (2) to provide greater supply chain transparency so that policymakers have the fact-based information needed to formulate public policy. This fact sheet focuses on the post-mining/pre-consumer-product part of the tantalum supply chain. The USGS National Minerals Information Center (NMIC) has been asked by governmental and non-governmental organizations to provide information about tantalum, tin, tungsten, and gold (collectively known as “3TG minerals”) processing facilities worldwide in response to U.S. legislation aimed at identifying and removing the supply chain links between the trade in these minerals and civil unrest in the Democratic Republic of the Congo and adjacent countries.

  11. Niger - Threshold (IMAGINE)

    Data.gov (United States)

    Millennium Challenge Corporation — The IMAGINE program was designed to improve educational outcomes of girls in Niger. The Millennium Challenge Corporation (MCC) funded IMAGINE as a component of its...

  12. Genetic analysis of Aspergillus niger

    NARCIS (Netherlands)

    Debets, F.

    1990-01-01

    Dit proefschrift handelt over genetische analyse van de voor de biotechnologie belangrijke schimmel Aspergillusniger . A.niger is een imperfecte schimmel, met andere woorden

  13. Mineral resources and exploration prospect in The Republic of Yemen%也门共和国矿产资源与矿业开发前景

    Institute of Scientific and Technical Information of China (English)

    李娜; 王靓靓; 元春华; 李玉龙

    2014-01-01

    也门共和国地处阿拉伯-努比亚(Arabian-Nubian)地盾,地质结构复杂多样,在火山岩和沉积岩区蕴藏着丰富的黄金、铅、银、铜、锌和其他金属矿产。也门的金矿主要位于Sana'a省,与火山和岩浆活动有关;铅锌矿成因类型较复杂,最大的铅锌矿产出于JabalSalab地区侏罗纪的白云岩中;铜镍矿存在于基性、超基性的侵入岩中,主要位于Taiz和Amran省。也门矿产资源丰富但大量矿床尚未被开发,有巨大的找矿潜力。本文结合也门矿产的资源情况及矿业开发现状圈定了优势矿产的找矿远景区,如Al Jawf省西部的金-银矿远景区,Sa'ada省北部的铜-镍矿远景区,以及Shabwah省东南部的锌-铅矿远景区等。也门共和国矿产资源丰富,矿业及税收政策宽松,定会成为未来矿业投资的热点区域。%The Republic of Yemen composes part of the Arabian -Nubian Shield .The geological conditions in Yemen and other factors are favourable for many types of mineral deposits ,like gold ,lead , silver ,copper and zinc .The gold deposit located in Sana'a is related to volcanic and magma activity ;the genetic type of lead-zinc deposit is complicated and the biggest deposit appeared in dolomite of Jurassic in JabalSalab region;copper-nickel deposit is located in Taiz and Amran ,in mafic and ultra-mafic intrusive rocks .The mineral potential of Yemen has not been explored .By analysing the mineral resource distribution and the current mineral exploration situation ,the author defined several prospect zones ,like Al Jawf for gold-silver deposit ,Sa'ada for copper-nickel deposit ,and Shabwah for zinc-lead deposits .With favourable mining and fax policy ,The Republic of Yemen will abstract more oversee investment and to be a hot spot for mineral exploration in the future .

  14. Object-based image analysis for the assessment of mineral extraction in conflict regions - a case study in the Democratic Republic of the Congo

    Science.gov (United States)

    Kranz, Olaf; Schoepfer, Elisabeth; Spröhnle, Kristin; Lang, Stefan

    2016-06-01

    In this study object-based image analysis (OBIA) techniques were applied to assess land cover changes related to mineral extraction in a conflict-affected area of the eastern Democratic Republic of the Congo (DRC) over a period of five years based on very high resolution (VHR) satellite data of different sensors. Object-based approaches explicitly consider spatio-temporal aspects which allow extracting important information to document mining activities. The use of remote sensing data as an independent, up-to-date and reliable data source provided hints on the general development of the mining sector in relation to socio-economic and political decisions. While in early 2010, the situation was still characterised by an intensification of mineral extraction, a mining ban between autumn 2010 and spring 2011 marked the starting point for a continuous decrease of mining activities. The latter can be substantiated through a decrease in the extend of the mining area as well as of the number of dwellings in the nearby settlement. A following demilitarisation and the mentioned need for accountability with respect to the origin of certain minerals led to organised, more industrialized exploitation. This development is likewise visible on satellite imagery as typical clearings within forested areas. The results of the continuous monitoring in turn facilitate non-governmental organisations (NGOs) to further foster the mentioned establishment of responsible supply chains by the mining industry throughout the entire period of investigation.

  15. Object-based image analysis for the assessment of mineral extraction in conflict regions – a case study in the Democratic Republic of the Congo

    Directory of Open Access Journals (Sweden)

    O. Kranz

    2016-06-01

    Full Text Available In this study object-based image analysis (OBIA techniques were applied to assess land cover changes related to mineral extraction in a conflict-affected area of the eastern Democratic Republic of the Congo (DRC over a period of five years based on very high resolution (VHR satellite data of different sensors. Object-based approaches explicitly consider spatio-temporal aspects which allow extracting important information to document mining activities. The use of remote sensing data as an independent, up-to-date and reliable data source provided hints on the general development of the mining sector in relation to socio-economic and political decisions. While in early 2010, the situation was still characterised by an intensification of mineral extraction, a mining ban between autumn 2010 and spring 2011 marked the starting point for a continuous decrease of mining activities. The latter can be substantiated through a decrease in the extend of the mining area as well as of the number of dwellings in the nearby settlement. A following demilitarisation and the mentioned need for accountability with respect to the origin of certain minerals led to organised, more industrialized exploitation. This development is likewise visible on satellite imagery as typical clearings within forested areas. The results of the continuous monitoring in turn facilitate non-governmental organisations (NGOs to further foster the mentioned establishment of responsible supply chains by the mining industry throughout the entire period of investigation.

  16. An estimate of the costs of an effective system of protected areas in the Niger Delta - Congo Basin Forest Region

    NARCIS (Netherlands)

    Blom, A.

    2004-01-01

    This paper presents an analysis of the costs of implementing a biodiversity conservation vision for the Niger Delta-Congo Basin Forest Region, a region covering the forests from Nigeria across Cameroon, Equatorial Guinea (EG), Gabon, Central African Republic (CAR), Congo and the Democratic Republic

  17. The influence of different vegetation patches on the spatial distribution of nests and the epigeic activity of ants (Lasius niger) on a spoil dump after brown coal mining (Czech Republic)

    Energy Technology Data Exchange (ETDEWEB)

    Holec, M.; Frouz, J.; Pokorny, R. [Academy of Science Czech Republic, Ceske Budejovice (Czech Republic). Inst. of Soil Biology

    2006-07-15

    A study was carried out during 2001 on mine tailings in NW Bohemia aimed at describing the spatial patterns of nests distribution and epigeic activity of ants in relation to the vegetation mosaic. Lasius niger was the most abundant species of ant and its nest mounds were significantly more numerous in patches with sparse vegetation than inside dense Calamagrostis epigejos vegetation; this was particularly true for small and medium-sized nests. Small and medium nests also occurred more frequently near the edges of a given patch than in the center. Large and medium nests were randomly distributed in the area, whereas small nests had an aggregated distribution. Pitfall trapping reveal significantly higher activity of L. niger workers in tall and dense vegetation stands in comparison with low and sparse vegetation. This pattern was particularly pronounced during the peak of foraging activity in summer and was not so significant in spring or autumn. We expect that ants preferentially forage in shaded habitats during the summer months when bare soil may be too hot. The results indicated that nesting and foraging may differ in their microclimatic requirements and the formation of vegetation mosaics may be important to changes in the ant population during succession.

  18. Minerals

    Directory of Open Access Journals (Sweden)

    Vaquero, M. P.

    1998-08-01

    Full Text Available The possible changes in the mineral composition of food during frying could be the consequence of losses by leaching, or changes in concentrations caused by exchanges between the food and culinary fat of other compounds. The net result depends on the type of food, the frying fat used and the frying process. Moreover, the modifications that frying produces in other nutrients could indirectly affect the availability of dietary minerals. The most outstanding ones are those that can take place in the fat or in the protein. With respect to the interactions between frying oils and minerals, we have recent knowledge concerning the effects of consuming vegetable oils used in repeated fryings of potatoes without turnover, on the nutritive utilization of dietary minerals. The experiments have been carried out in pregnant and growing rats, which consumed diets containing, as a sole source of fat, the testing frying oils or unused oils. It seems that the consumption of various frying oils, with a polar compound content lower or close to the maximum limit of 25% accepted for human consumption, does not alter the absorption and metabolism of calcium, phosphorous, iron or copper. Magnesium absorption from diets containing frying oils tends to increase but the urinary excretion of this element increases, resulting imperceptible the variations in the magnesium balance. The urinary excretion of Zn also increased although its balance remained unchanged. Different studies referring to the effects of consuming fried fatty fish on mineral bioavailability will also be presented. On one hand, frying can cause structural changes in fish protein, which are associated with an increase in iron absorption and a decrease in body zinc retention. The nutritive utilization of other elements such as magnesium, calcium and copper seems to be unaffected. On the other hand; it has been described that an excess of fish fatty acids in the diet produces iron depletion, but when fatty

  19. Hydrogeological investigations for mineral water and CO2 gas in the village of Bac, Bitola, The Republic of Macedonia

    OpenAIRE

    2005-01-01

    Tree exploration drill holes were dug in the Neogene Middle Pliocene sediments in the vicinity of the village of Bac for the investigation of the mineral water and CO2 gas. The first drill hole (B 1) was dug 30 m in depth indicated a water bearing horizon in o to 26.4 m thick grey marly sandstone with a free level aquifer and ground water 2.2 m at depth and yield of 10l/s. The second and third drill holes (ED-1 and ED-2) were dug 301 m to depth and determined a free level aquifer, a sub ar...

  20. Drill Core Mineral Analysis by Means of the Hyperspectral Imaging Spectrometer HySpex, XRD and Asd in Proximity of the MÝTINA Maar, Czech Republic

    Science.gov (United States)

    Koerting, F.; Rogass, C.; Kaempf, H.; Lubitz, C.; Harms, U.; Schudack, M.; Kokaly, R.; Mielke, C.; Boesche, N.; Altenberger, U.

    2015-12-01

    Imaging spectroscopy is increasingly used for surface mapping. Therefore different expert systems are being utilized to identify surface cover materials. Those expert systems mainly rely on the spectral comparison between unknown and library spectra, but their performances were only limited qualified. This study aims on the comparative analysis of drill core samples from the recently discovered maar system in the Czech Republic. Drill core samples from the surrounding area of the Mýtina maar were analyzed by X-Ray diffraction (XRD) and the hyperspectral spectrometer HySpex. Additionally, soil samples were measured in-situ by the ASD FieldSpec4 and in the laboratory by the HySpex VNIR/SWIR spectrometer system. The data was then analyzed by the MICA-algorithm and the results were compared to the results of the XRD -analysis. The XRD-analysis served here as validation basis. The results of the hyperspectral and the XRD analyses were used to densify a volcanic map that also integrates in-situ soil measurements in the surrounding area of Mýtina. The comparison of the XRD- and solaroptical remote sensing results showed a good correlation of qualified minerals if the soil organic carbon content was significantly low. Contrary to XRD, smectites and muscovites were also straightforward identified that underlines the overall performance of the approach to identify minerals. Basically, in this work an operable approach is proposed that enables the fast, repeatable and detailed analysis of drill cores, drill core samples and soil samples and, hence, provides a higher performance than state-of-the-art XRD-analyses.

  1. Areva in Niger

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-02-01

    Niger is the second poorest country in the world but it has natural resources underground in the form of uranium ores deposits. This uranium is currently mined by two companies incorporated under Nigerian law: Somair and Cominak, operated by the principal shareholder Areva (through its subsidiary Cogema). After a presentation of Somair and Cominak key figures, this document details the working conditions and radiological protection, the environmentally friendly operations, the production traceability, the local economic development, the strengthening of the health care system and the development of the infrastructure. (A.L.B.)

  2. Differences of some indicators of raw milk properties and especially mineral composition between small ruminants as compared to cows in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Oto Hanuš

    2008-01-01

    Full Text Available Sheep and goat farming is returning back into the Czech Republic (CR because of positive effects of alternative milk consumption on human health. Especially the elements Ca and Mg are important for nutrition. Paper presents the comparison of mineral milk composition of goats (White short–haired–W, n = 60, sheep (Tsigai–C, n = 60 and cows (Holstein–H, n = 36; Czech Fleckvieh–B, n = 93. Cow milk results were considered as reference. The herds were kept at altitude 260 m (H, 360 m (B, and 572 m above sea level (W, C with total precipitation 449, 700 and 1200 mm per year and mean air temperatures 9.6, 7.0 and 3.7 °C. Bulk milk samples (4–8 animals in sample from the first two thirds of the lactation and the winter and summer season were investigated. Goat milk freezing point differed from other species (P < 0.001, −0.6048 for C < −0.5544 W < −0.5320 H < −0.5221 °C for B. Cow milk Ca values were comparable to former results although milk yield (MY was higher. Along lower MY the Ca was higher (1299.6 > 1172.0 mg . kg−1; P < 0.001 in B than H, similar trend was in Mg (122.0 > 107.4 mg . kg−1; P<0.001. Differences (P > 0.05 between species were in Ni and also mostly in Cu. Iodine results differed between species but not between cow breeds (P < 0.001; 462.8 H and 434.9 B > 126.0 W and 164.2 μg . l−1 C. It could be explainable by using of I disinfection at teat treatment in cows and absence of treatment in small ruminants. Macroelements were mostly highest (Ca, P, Na, Mg in sheep milk, with exception of K. Phosphorus values (950.1 H, 1016.9 B, 1042.6 W and 1596.7 mg . kg−1 C in species were linked with crude or true protein and casein values. Small ruminant milk could be good source of minerals for human nutrition, especially in the case of Ca and Mg of sheep and goat milk.

  3. Regulatory processes in Aspergillus niger

    DEFF Research Database (Denmark)

    Poulsen, Lars

    Filamentous fungi are extensively used in the fermentation industry for synthesis of numerous products. One of the most important, is the fungus Aspergillus niger, used industrially for production of organic acids, and homologous as well as heterologous enzymes. This fungus has numerous of advant......Filamentous fungi are extensively used in the fermentation industry for synthesis of numerous products. One of the most important, is the fungus Aspergillus niger, used industrially for production of organic acids, and homologous as well as heterologous enzymes. This fungus has numerous...

  4. UTILIZING Aspergillus niger FOR BIOREMEDIATION OF TANNERY EFFLUENT

    Directory of Open Access Journals (Sweden)

    Jyoti Bisht

    2014-03-01

    Full Text Available Tannery waste water is characterized by highly toxic ammonium, sulfates, surfactants, acids, dyes, sulfonated oils and organic substances, including natural or synthetic tannins. This study was designed to study the potential of Aspergillus niger for bioremediation of tannery effluent. Addition of glucose as a carbon source in the tannery effluent encouraged the growth of A. niger but there was no change in physico-chemical parameters. The toxic effects were mostly reduced after treatment when 20% mineral salt medium was added in tannery effluent. Colour, COD, TS, TDS, TSS, chlorides, sulfides and chromium reduction were 71.9%, 72.1%, 69.0%, 65.0%, 68.1%, 66.8%, 65.7% and 57.8%, respectively.

  5. Chemical and Pharmacological Researches on Hyoscyamus niger

    Institute of Scientific and Technical Information of China (English)

    LI Jun; SHI Ji; YU Xin-wen; SUN Jing-kuan; MEN Qi-ming; KANG Ting-guo

    2011-01-01

    The reports on chemical constituents of Hyoscyamus niger were summarized. The compounds include alkaloids, saponins, lignans, coumarinolignans, flavonoids, and some other nonalkaloidal compounds. TLC, HPLC, and GC were used for the qualitative and quantitative analyses of some chemical constituents in H. niger. Modern pharmacological experiments showed that H. niger had the analgesic, anti-inflammatory, antipyretic, anticonvulsant, spasmolytic, antidiarrhoeal, antisecretory, bronchodilatory, urinary bladder relaxant, hypotensive, cardiosuppressant, vasodilator, antitumor, and feeding deterrent properties. In addition, the toxicities of this medicinal plant were also described.

  6. Morphogenesis and protein production in Aspergillus niger

    NARCIS (Netherlands)

    Kwon, Min Jin

    2014-01-01

    The research described in this thesis aims to get more fundamental insights in the molecular mechanisms used by Aspergillus niger in relation to control morphology and protein secretion. Knowledge on these two aspects is highly relevant to further optimization of A.niger as a cell factory

  7. Sporulation inhibited secretion in Aspergillus niger

    NARCIS (Netherlands)

    Krijgsheld, P.

    2013-01-01

    Aspergillus niger is abundantly found in nature. It degrades dead material of plants and animals but can also be a pathogen of these organisms. Aspergillus niger is also important for mankind because it is one of the main organisms used for the industrial production of enzymes. These enzymes are rel

  8. The Niger Delta Amnesty Program

    Directory of Open Access Journals (Sweden)

    Benjamin A. Okonofua

    2016-06-01

    Full Text Available The armed conflict between militias and government forces in Nigeria’s Niger Delta region has spanned for more than two decades, defying all solutions. A disarmament, demobilization, and reintegration (DDR program was established in August 2015 in effort to end the violence and has remained in place. It is a radically different approach from past approaches that displayed zero tolerance to all political challenges to oil production or the allocation of oil profits. The approach appeared to be immediately successful in that it forced a ceasefire, engaged militants in planned programs to rehabilitate and reintegrate them into civilian society, and opened up the oil wells (many of which had been shut due to the crisis with the effect of increasing government revenue, which depends 85% on oil exports. Yet, few studies have attempted to understand the dynamics within the country that are responsible for the design and implementation of this broad policy shift or to understand whether and how the current initiative is able to end the conflict and institute peace beyond the short term. This study, therefore, is important because it provides a critical perspective that anticipates and explains emerging issues with the Niger Delta Amnesty Program, which have implications for DDR adaptation and implementation all over the world. Ultimately, the research demonstrates how the DDR program both transforms the Niger Delta conflict and becomes embroiled in intense contestations not only about the mechanism for transforming the targeted population but also whether and how the program incorporates women who are being deprioritized by the program.

  9. Regulatory processes in Aspergillus niger

    DEFF Research Database (Denmark)

    Poulsen, Lars

    some disadvantages as well, those are byproduct formation, secretion of proteolytic enzymes and formation of mycotoxins. The aim of this project was to reduce these disadvantages, though investigating the regulatory processes. The first objective was to study the regulatory events leading to A. niger......T. The physiological batch characterization showed that the ΔprtT strain had the lowest protease activity (fivefold reduced), but also featured excessive CO2 yield, reduced growth rate and lower biomass yields. The ΔprtB strain had a close to twofold reduced levels of secreted proteases but with additional beneficial...

  10. Discovery of a leptospirosis cluster amidst a pneumonic plague outbreak in a miners' camp in the Democratic Republic of the Congo.

    Science.gov (United States)

    Bertherat, Eric; Mueller, Melissa J; Shako, Jean-Christophe; Picardeau, Mathieu

    2014-02-07

    Conditions in the Democratic Republic of the Congo provide an ideal environment for leptospirosis and plague, both of which can cause severe pulmonary manifestations. In December 2004, an outbreak of lethal pneumonia occurred in a local mining camp, affecting 130 persons and killing 57 of them. Clinical signs, fast disease spread, and initial laboratory investigations suggested pneumonic plague. While leptospirosis had not recently been described in the region, it was considered as a differential diagnosis. Anti-Leptospira antibodies were detected by microscopic agglutination test (MAT). A confirmed case of leptospirosis was defined as having consistent clinical signs and any one of the following: seroconversion or four-fold increase in MAT titre for paired serum samples, or a MAT titre ≥ 1:400 for acute-phase serum samples. Twenty-nine of the 54 patients or convalescents tested for leptospirosis were seropositive. Two cases showed a confirmed infection for both plague and leptospirosis. While evidence supports the plague nature of this outbreak, the results suggest that some of the suspected plague cases might be due to leptospirosis. In any case, this diagnosis will have to be evoked in the future if a similar outbreak occurs in this region of Africa.

  11. Mineral Classification of Land Surface Using Multispectral LWIR and Hyperspectral SWIR Remote-Sensing Data. A Case Study over the Sokolov Lignite Open-Pit Mines, the Czech Republic

    Directory of Open Access Journals (Sweden)

    Gila Notesco

    2014-07-01

    Full Text Available Remote-sensing techniques offer an efficient alternative for mapping mining environments and assessing the impacts of mining activities. Airborne multispectral data in the thermal region and hyperspectral data in the optical region, acquired with the Airborne Hyperspectral Scanner (AHS sensor over the Sokolov lignite open-pit mines in the Czech Republic, were analyzed. The emissivity spectrum was calculated for each vegetation-free land pixel in the longwave infrared (LWIR-region image using the surface-emitted radiation, and the reflectance spectrum was derived from the visible, near-infrared and shortwave-infrared (VNIR–SWIR-region image using the solar radiation reflected from the surface, after applying atmospheric correction. The combination of calculated emissivity, with the ability to detect quartz, and SWIR reflectance spectra, detecting phyllosilicates and kaolinite in particular, enabled estimating the content of the dominant minerals in the exposed surface. The difference between the emissivity values at λ = 9.68 µm and 8.77 µm was found to be a useful index for estimating the relative amount of quartz in each land pixel in the LWIR image. The absorption depth at around 2.2 µm in the reflectance spectra was used to estimate the relative amount of kaolinite in each land pixel in the SWIR image. The resulting maps of the spatial distribution of quartz and kaolinite were found to be in accordance with the geological nature and origin of the exposed surfaces and demonstrated the benefit of using data from both thermal and optical spectral regions to map the abundance of the major minerals around the mines.

  12. in the Niger Delta of Nigeria

    African Journals Online (AJOL)

    suggestions as policy options for the resolution of the armed conflict in the. Niger Delta ... indiscriminate use of lethal weapons by local militias, the cumulative effect of which is the ... of many 'child' soldiers in local conflicts or wars nowadays.

  13. Litochlebite, Ag2PbBi4Se8, a new selenide mineral species from Zalesi, Czech Republic: description and crystal structure

    DEFF Research Database (Denmark)

    Makovicky, Emil; Topa, Dan; Sejkora, Jiri;

    2011-01-01

    , and uranophane. Litochlebite is opaque, dark grey to black, has a dark grey streak and a metallic luster. No cleavage was observed; the mineral is brittle with an irregular fracture. The VHN10g microhardness 230 (227–234) kg/mm2 corresponds to a Mohs hardness of about 3; the calculated density is 7.90 g/cm3...... [Fo > 4s(Fo)] collected on a Bruker AXS diffractometer with a CCD detector and MoKa radiation. The crystal structure contains one lead site, four independent Bi sites, four silver sites and eight independent Se sites. One Ag site is an octahedrally coordinated (2 + 4) site in the pseudotetragonal...

  14. Genetic aspects of barite mineralization related to rocks of the teschenite association in the Silesian Unit, Outer Western Carpathians, Czech Republic

    Science.gov (United States)

    Jirásek, Jakub; Dolníček, Zdeněk; Matýsek, Dalibor; Urubek, Tomáš

    2017-04-01

    Barite is a relatively uncommon phase in vein and amygdule mineralizations hosted by igneous rocks of the teschenite association in the Silesian Unit (Western Carpathians). In macroscopically observable sizes, it has been reported from 10 sites situated only in the Czech part of the Silesian Unit. Microscopic barite produced by the hydrothermal alteration of rock matrix and also by the supergene processes is more abundant. We examined four samples of barite by mineralogical and geochemical methods. Electron microprobe analyses proved pure barites with up to 0.038 apfu Sr and without remarkable internal zonation. Fluid inclusion and sulphur isotope data suggests that multiple sources of fluid components have been involved during barite crystallization. Barite contains primary and secondary aqueous all-liquid (L) or less frequent two-phase (L+V) aqueous fluid inclusions with variable salinity (0.4-2.9 wt. % NaCl eq.) and homogenization temperatures between 77 and 152 °C. The higher-salinity fluid endmember was probably Cretaceous seawater and the lower-salinity one was probably diagenetic water derived from surrounding flysch sediments during compaction and thermal alteration of clay minerals. The δ34S values of barite samples range between -1.0 ‰ and +16.4 ‰ CDT suggesting participation of two sources of sulphate, one with a near-zero δ34S values probably derived from wall rocks and another with high δ34S values being most probably sulphate from the Cretaceous seawater. All results underline the role of externally derived fluids during post-magmatic alteration of bodies of rock of the teschenite association.

  15. Genetic aspects of barite mineralization related to rocks of the teschenite association in the Silesian Unit, Outer Western Carpathians, Czech Republic

    Directory of Open Access Journals (Sweden)

    Jirásek Jakub

    2017-04-01

    Full Text Available Barite is a relatively uncommon phase in vein and amygdule mineralizations hosted by igneous rocks of the teschenite association in the Silesian Unit (Western Carpathians. In macroscopically observable sizes, it has been reported from 10 sites situated only in the Czech part of the Silesian Unit. Microscopic barite produced by the hydrothermal alteration of rock matrix and also by the supergene processes is more abundant. We examined four samples of barite by mineralogical and geochemical methods. Electron microprobe analyses proved pure barites with up to 0.038 apfu Sr and without remarkable internal zonation. Fluid inclusion and sulphur isotope data suggests that multiple sources of fluid components have been involved during barite crystallization. Barite contains primary and secondary aqueous all-liquid (L or less frequent two-phase (L+V aqueous fluid inclusions with variable salinity (0.4-2.9 wt. % NaCl eq. and homogenization temperatures between 77 and 152 °C. The higher-salinity fluid endmember was probably Cretaceous seawater and the lower-salinity one was probably diagenetic water derived from surrounding flysch sediments during compaction and thermal alteration of clay minerals. The δ34S values of barite samples range between -1.0 ‰ and +16.4 ‰ CDT suggesting participation of two sources of sulphate, one with a near-zero δ34S values probably derived from wall rocks and another with high δ34S values being most probably sulphate from the Cretaceous seawater. All results underline the role of externally derived fluids during post-magmatic alteration of bodies of rock of the teschenite association.

  16. Parasites and mortality of Sable Hippotragus niger niger (harris, 1838 in the Matopos, Zimbabwe

    Directory of Open Access Journals (Sweden)

    J. H Grobler

    1981-01-01

    Full Text Available Parasitism is indicated as the main cause of mortality of sable Hippotragus niger niger in Matopos, Zimbabwe. The main external parasites were Rhipicephalus appendiculatus, R. evertsi and the larvae of Chrysomya bezziana. The main internal parasite was Haemonchus and to a lesser extent Taenia multiceps. Babesia and anaplasmosis were identified in blood smears.

  17. 75 FR 80947 - Conflict Minerals

    Science.gov (United States)

    2010-12-23

    ... violence in the eastern Democratic Republic of the Congo, particularly sexual- and gender-based violence... conflict free,'' the facilities used to process the conflict minerals, the country of origin of the conflict minerals, and ``the efforts to determine the mine or location of origin with the greatest...

  18. Effect of additional molasses to xylanase enzyme production by fungi Aspergillus niger with rice straw substrate

    Directory of Open Access Journals (Sweden)

    ESTU RETNANINGTYAS N

    2012-11-01

    Full Text Available Pangesti NWI, Pangastuti A, Retnaningtyas NE. 2012. Pengaruh penambahan molase pada produksi enzim xilanase oleh fungi Aspergillus niger dengan substrat jerami padi.. Bioteknologi 9: 41-48. Dalam rangka mendapatkan bahan alternatif yang berharga murah dan mudah diperoleh untuk menghasilkan xilanase, maka dilakukan penelitian produksi enzim xilanase dari jerami padi dan molase. Jerami padi dapat digunakan sebagai pengganti substrat xilan yang mahal, sementara molase diperlukan sebagai sumber karbon, nitrogen, mineral dan nutrisi bagi pertumbuhan mikroba sehingga dapat menghasilkan enzim. Tujuan penelitian ini adalah untuk mengetahui pengaruh penambahan molase pada produksi enzim xilanase oleh jamur Aspergillus niger dengan substrat jerami padi. Penelitian ini dibagi menjadi tiga tahap, yaitu tahap persiapan, produksi enzim dan pengujian. Tahap persiapan meliputi pengembangbiakan strain jamur, persiapan inokulum, dan persiapan media fermentasi. Pada tahap produksi enzim, A. niger ditumbuhkan dalam medium cair dengan substrat jerami padi yang diserbuk. Pada medium fermentasi, ditambahkan molase dengan variasi 0%, 1%, 3%, dan 5%. Proses fermentasi dilakukan dalam inkubator shaker pada suhu 37°C, agitasi 200 rpm dan pH 6. Terakhir, pengujian reduksi kadar gula menggunakan metode DNS untuk mendapatkan aktivitas enzim yang telah diproduksi. Dari hasil penelitian diketahui bahwa penambahan molase pada media jerami padi dapat meningkatkan pertumbuhan jamur A. niger, tetapi tidak dapat meningkatkan aktivitas enzim xylanase secara signifikan dan membutuhkan waktu inkubasi lebih lama. Konsentrasi yang paling optimal dari molase untuk produksi enzim xylanase adalah 1% dengan aktivitas enzim tertinggi sebesar 0,055 U/mL dan dengan waktu inkubasi 56 jam.

  19. The Niger Delta Avengers, Autonomous Ethnic Clans and Common ...

    African Journals Online (AJOL)

    Nneka Umera-Okeke

    The situation in Niger Delta region has remained an unanswered research question. When oil was discovered .... From the foregone analysis, the greed factor is sufficient to explain the crisis in Niger. Delta given the ..... homeless. The sizeable ...

  20. Struggling for Water and Pastures in Niger

    DEFF Research Database (Denmark)

    Cold-Ravnkilde, Signe Marie

    inform natural resource struggles on the ground and reveals that points of contest between universalism and cultural relativism in regard to property, public authority and justice are reflected in both national legislation and in international development practices. On the basis of a sensitive study......In Niger the question of rights to pastoral resources illustrates how ideologies in Western mindset have been transported to the African continent. On the on hand there has been an attempt to standardise legal frameworks and land tenure practices with uniform rules. On the other hand, since...... the 1990s customary practices are increasingly recognised in legal frameworks. "Struggling for water and pastures in Niger" explores the philosophical assumptions behind the rules governing rights to water and pastures in the pastoral areas of the Diffa region in Niger. The book shows how these assumptions...

  1. An artificially constructed Syngonium podophyllum-Aspergillus niger combinate system for removal of uranium from wastewater.

    Science.gov (United States)

    He, Jia-dong; Wang, Yong-dong; Hu, Nan; Ding, Dexin; Sun, Jing; Deng, Qin-wen; Li, Chang-wu; Xu, Fei

    2015-12-01

    Aspergillus niger was inoculated to the roots of five plants, and the Syngonium podophyllum-A. niger combinate system (SPANCS) was found to be the most effective in removing uranium from hydroponic liquid with initial uranium concentration of 5 mg L(-1). Furthermore, the hydroponic experiments on the removal of uranium from the hydroponic liquids with initial uranium concentrations of 0.5, 1.0, and 3.0 mg L(-1) by the SPANCS were conducted, the inhibitory effect of A. niger on the growth of S. podophyllum in the SPANCS was studied, the accumulation characteristics of uranium by S. podophyllum in the SPANCS were analyzed, and the Fourier transform infrared (FT-IR) and extended X-ray absorption fine structure (EXAFS) spectra were measured. The results show that the removal of uranium by the SPANCS from the hydroponic liquids with initial uranium concentrations of 0.5, 1.0, and 3.0 mg L(-1) reached 98.20, 97.90, and 98.50%, respectively, after 37 days of accumulation of uranium; that the uranium concentrations in the hydroponic liquids decreased to 0.009, 0.021, and 0.045 mg L(-1), respectively, which are lower than the stipulated concentration for discharge of 0.050 mg L(-1) by the People's Republic of China; that A. niger helped to generate more groups in the root of S. podophyllum which can improve the complexing capability of S. podophyllum for uranium; and that the uranium accumulated in the root of S. podophyllum was in the form of phosphate uranyl and carboxylic uranyl.

  2. Struggling for Water and Pastures in Niger

    DEFF Research Database (Denmark)

    Cold-Ravnkilde, Signe Marie

    of struggles over water and pastures in Diffa, Signe Marie Cold-Ravnkilde accounts for the outcome of conflict and cooperation and explains why herders, like people in other cultures, conceive of their rights in a contradictory manner: as requiring adoption to cultural specific conditions and yet applies...... the 1990s customary practices are increasingly recognised in legal frameworks. "Struggling for water and pastures in Niger" explores the philosophical assumptions behind the rules governing rights to water and pastures in the pastoral areas of the Diffa region in Niger. The book shows how these assumptions...

  3. Mineral potential tracts for orogenic, Carlin-like, and epithermal gold deposits in the Islamic Republic of Mauritania, (phase V, deliverable 68): Chapter H1 in Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)

    Science.gov (United States)

    Goldfarb, Richard J.; Marsh, Erin; Horton, John D.

    2012-01-01

    In 1996, at the request of the Government of the Islamic Republic of Mauritania, a team of U.S. Geological Survey (USGS) scientists produced a strategic plan for the acquisition, improvement and modernization of multidisciplinary sets of data to support the growth of the Mauritanian minerals sector and to highlight the geological and mineral exploration potential of the country. In 1999, the Ministry of Petroleum, Energy, and Mines of the Islamic Republic of Mauritania implemented a program for the acquisition of the recommended basic geoscientific information, termed the first Projet de Renforcement Institutionnel du Secteur Minier (Project for Institutional Capacity Building in the Mining Sector, PRISM-I). As a result of the PRISM-I efforts, a great deal of new geological, geophysical, geochemical, remote sensing, and hydrological data became available for evaluation and synthesis. However, the Ministry of Petroleum, Energy, and Mines recognized that additional work was required to extract the full benefit of the data before it could be of greatest use to the international community and of benefit to the Mauritanian minerals and development sector.

  4. Reported industrial minerals occurrences and permissive areas for other occurrences in the Islamic Republic of Mauritania (phase V deliverable 88): Chapter R1 in Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)

    Science.gov (United States)

    Langer, William H.; Anderson, Eric D.; Horton, John D.

    2012-01-01

    In 1996, at the request of the Government of the Islamic Republic of Mauritania, a team of U.S. Geological Survey (USGS) scientists produced a strategic plan for the acquisition, improvement and modernization of multidisciplinary sets of data to support the growth of the Mauritanian minerals sector and to highlight the geological and mineral exploration potential of the country. In 1999, the Ministry of Petroleum, Energy, and Mines of the Islamic Republic of Mauritania implemented a program for the acquisition of the recommended basic geoscientific information, termed the first Projet de Renforcement Institutionnel du Secteur Minier (Project for Institutional Capacity Building in the Mining Sector, PRISM-I). As a result of the PRISM-I efforts, a great deal of new geological, geophysical, geochemical, remote sensing, and hydrological data became available for evaluation and synthesis. However, the Ministry of Petroleum, Energy, and Mines recognized that additional work was required to extract the full benefit of the data before it could be of greatest use to the international community and of benefit to the Mauritanian minerals and development sector.

  5. On the safety of Aspergillus niger - a review

    DEFF Research Database (Denmark)

    Schuster, E.; Dunn-Coleman, N.; Frisvad, Jens Christian

    2002-01-01

    Aspergillus niger is one of the most important microorganisms used in biotechnology. It has been in use already for many decades to produce extracellular (food) enzymes and citric acid. In fact, citric acid and many A. niger enzymes are considered GRAS by the United States Food and Drug...... retrieval reasons and there is a taxonomical consensus based on molecular data that the only other common species closely related to A. niger in the Aspergillus series Nigri is A. tubingensis. A. niger, like other filamentous fungi, should be treated carefully to avoid the formation of spore dust. However...... Administration. In addition, A. niger is used for biotransformations and waste treatment. In the last two decades, A. niger has been developed as an important transformation host to over-express food enzymes. Being pre-dated by older names, the name A. niger has been conserved for economical and information...

  6. Organic acid production by Aspergillus niger

    DEFF Research Database (Denmark)

    Jongh, Wian de

    2006-01-01

    . Specielt Aspergillus niger er interessant i forbindelse med produktion af organiske syrer, idet denne organisme tolerer lavt pH, kan give høje produktudbytter, og kan give høje produktiviteter som allerede illustreret i anvendelsen af denne organisme i produktionen af citronsyre. Disse faktorer gør A...

  7. Differentiation in colonies of Aspergillus niger

    NARCIS (Netherlands)

    Levin Chucrel, A.M.

    2007-01-01

    The aim of this Thesis was to study genome-wide gene expression in colonies of A. niger and to relate this to nutrient availability, growth, and secretion. Maltose and xylose were chosen as carbon sources for this study. These compounds result in different sets of extracellular enzymes. In Chapter 2

  8. Characterisation of Aspergillus niger prolyl aminopeptidase

    NARCIS (Netherlands)

    Basten, E.J.W.; Moers, A.P.H.A.; Ooyen, van A.J.J.; Schaap, P.J.

    2005-01-01

    We have cloned a gene (papA) that encodes a prolyl aminopeptidase from Aspergillus niger. Homologous genes are present in the genomes of the Eurotiales A. nidulans, A. fumigatus and Talaromyces emersonii, but the gene is not present in the genome of the yeast Saccharomyces cerevisiae. Cell extracts

  9. Significance and occurrence of fumonisins from Aspergillus niger

    DEFF Research Database (Denmark)

    Mogensen, Jesper Mølgaard

    Fumonisins is a well-studied group of mycotoxins, mainly produced in maize by Fusarium species. However with the recent discovery of a fumonisin production by Aspergillus niger, other food commodities are at risk, since A. niger is a ubiquitous contaminant of many food and feed products....... The objective of this thesis was to determine the significance and occurrence of fumonisins from Aspergillus niger in food, the frequency of fumonisin production in A. niger isolates, as well as studies of the effect of physiological factors affecting fumonisin production. Major findings in this context have...... been the ocumentation of the production of fumonisins in raisins and peanuts, and occurrence of A. niger derived fumonisins in retail wine and raisins. Physiological investigations have demonstrated that fumonisin production in A. niger occurs at temperatures between 20-37 °C. Three water activity...

  10. Aspergillus Niger Genomics: Past, Present and into the Future

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Scott E.

    2006-09-01

    Aspergillus niger is a filamentous ascomycete fungus that is ubiquitous in the environment and has been implicated in opportunistic infections of humans. In addition to its role as an opportunistic human pathogen, A. niger is economically important as a fermentation organism used for the production of citric acid. Industrial citric acid production by A. niger represents one of the most efficient, highest yield bioprocesses in use currently by industry. The genome size of A. niger is estimated to be between 35.5 and 38.5 megabases (Mb) divided among eight chromosomes/linkage groups that vary in size from 3.5 - 6.6 Mb. Currently, there are three independent A. niger genome projects, an indication of the economic importance of this organism. The rich amount of data resulting from these multiple A. niger genome sequences will be used for basic and applied research programs applicable to fermentation process development, morphology and pathogenicity.

  11. Corruption, Insecurity and Border control in Niger

    DEFF Research Database (Denmark)

    Hahonou, Eric Komlavi

    In Niger, building more border offices has proven insufficient to tackle the spread of smuggling, drug trade and circulation of jihadists in the Sahel. Instead, everyday petty corruption makes border control ineffective and, while apparently benign, this has severe consequences in contexts...... of volatile security. In this policy brief, Eric Hahonou argues that without complementary activities, the multiplication of border offices could even expand opportunities for corruption. Instead, security policy should focus on creating a culture of effectiveness including systematic and regular staff...... meetings, reporting, law implementation and sanctions as well as new modalities to reward border guards and other state agents. Because corruption is, to a large extent, embedded in the social norms of the users of public service in Niger, sensitisation among transporters, passengers and traders is crucial....

  12. 21 CFR 173.120 - Carbohydrase and cellulase derived from Aspergillus niger.

    Science.gov (United States)

    2010-04-01

    ... cellulase derived from Aspergillus niger. Carbohydrase and cellulase enzyme preparation derived from Aspergillus niger may be safely used in food in accordance with the following prescribed conditions: (a) Aspergillus niger is classified as follows: Class, Deuteromycetes; order, Moniliales; family,...

  13. The Production of Itaconic Acid from Sweet Potato Peel Using Aspergillus niger and Aspergillus terreus

    Directory of Open Access Journals (Sweden)

    OMOJASOLA PATRICIA FOLAKEMI

    2014-12-01

    Full Text Available Accumulation of large quantities of agricultural residues results in deterioration of the environment and biomass loss which could be processed to yield value-added products like fuels and a variety of acids. The quest for a solution led to the fermentation of Ipomoea batatas using fungi. Aspergillus niger (ATCC 16404 and Aspergillus terreus (ATCC 20542 were used to ferment sweet potato peel (SPP, an agro-based waste. The physico-chemical analysis of the SPP was carried out. SPP was dried, ground, pre-treated with alkali and steam, re-dried and used as substrate in media containing mineral salt medium and inocula of A. niger and A. terreus. Fermentation was submerged at pH 5.0; 10% substrate concentration; 10 mL inocula size; temperature 250 C for five days with carboxylmethylcellulose (CMC as control. Optimization experiments were conducted by varying fermentation parameters. Results of physico-chemical analysis revealed carbohydrate 65.9%; sugars 22.60%; protein 5.38%; fibre 3.48%; fat 4.0% ash 4.02% and moisture 8.13%. Itaconic acid yield of 67.67+1.20 mg mL-1 and 70.67+2.60 mg mL-1 produced by A. niger and A. terreus from SPP respectively. The CMC yielded 3.00 +0.6 mg mL-1. Results of the optimization experiments showed higher yields of itaconic acid by A. niger and A. terreus to 112.67+5.20 mg mL-1 and 115.67+5.30 mg mL-1 from SPP respectively at pH 4.0; 10% substrate concentration; 5 mL inocula size on Day-5 of the fermentation. This represented an increase in product yield by both organisms and supports the potential use of this waste for the industrial production of itaconic acid.

  14. Decoupled Changes in Western Niger Delta Primary Productivity and Niger River Discharge Across the Last Deglacial

    Science.gov (United States)

    Parker, A. O.; Schmidt, M. W.; Slowey, N. C.; Jobe, Z. R.; Marcantonio, F.

    2014-12-01

    Abrupt droughts in West Africa impart significant socio-economic impacts on the developing countries of this region, and yet a comprehensive understanding of the causes and duration of such droughts remains elusive. Much of the summertime rainfall associated with the West African Monsoon (WAM) falls within the Niger River basin and eventually drains into the eastern Gulf of Guinea, contributing to the low sea-surface salinity of this region. Of the limited number of studies that reconstruct Gulf of Guinea salinity through the deglacial, the most comprehensive of those is located ~ 400 km east of the Niger delta and may not be solely influenced by WAM runoff. Here, we present XRF and foraminiferal trace metal data from two new cores located less than 100 km from the Western Niger Delta. Radiocarbon dating of cores Grand 21 (4.72oN, 4.48oE) and Fan 17 (4.81oN, 4.41oE) produced near linear sedimentation rates of 20 cm/kyr and 15 cm/kyr respectively. Elemental sediment compositions from XRF core scanning reveal an abrupt 50% increase in SiO2 between 17-15 ka during Heinrich Event 1. This increase, coeval with increases of CaCO3 (+12%) content and Ba/Ti ratios suggests a large increase in primary productivity during H1. Values then decrease at the onset of the Bolling-Allerod (~14.6 kyr) until a similar, albeit smaller increase is recorded during the Younger Dryas beginning at 12.7 kyr. In contrast, FeO2 and TiO2 are thought to be a proxies of Niger River discharge strength and suggest a more gradual change in riverine discharge across the deglacial that is most likely driven by precession. These proxies suggest Niger River runoff was low from the LGM through Heinrich 1, gradually increasing around 13 ka. FeO2 and TiO2 values then peak between 11.5-7.5 kyr, consistent with the African Humid Period, before gradually decreasing through the mid-late Holocene. This deglacial pattern of riverine input is markedly different from previous reconstructions of WAM variability and

  15. Inhibition of secretion by asexual reproduction in Aspergillus niger

    NARCIS (Netherlands)

    Wang, Fengfeng

    2014-01-01

    The aim of this Thesis was to study mechanism involved in zonal secretion in colonies of A. niger with emphasis on sporulation inhibited secretion. These mechanisms may be targets to improve A. nigeras a cell factory. I focused in particular on A. niger homologues of fluG and veA that are known spor

  16. Database of mineral deposits in the Islamic Republic of Mauritania (phase V, deliverables 90 and 91): Chapter S in Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)

    Science.gov (United States)

    Marsh, Erin; Anderson, Eric D.

    2015-01-01

    Three ore deposits databases from previous studies were evaluated and combined with new known mineral occurrences into one database, which can now be used to manage information about the known mineral occurrences of Mauritania. The Microsoft Access 2010 database opens with the list of tables and forms held within the database and a Switchboard control panel from which to easily navigate through the existing mineral deposit data and to enter data for new deposit locations. The database is a helpful tool for the organization of the basic information about the mineral occurrences of Mauritania. It is suggested the database be administered by a single operator in order to avoid data overlap and override that can result from shared real time data entry. It is proposed that the mineral occurrence database be used in concert with the geologic maps, geophysics and geochemistry datasets, as a publically advertised interface for the abundant geospatial information that the Mauritanian government can provide to interested parties.

  17. Biocatalytic Resolution of para-Nitrostyrene Oxide by Resting Cells of Different Aspergillus niger Strains

    Institute of Scientific and Technical Information of China (English)

    金浩; 李祖义; 王清

    2001-01-01

    Biocatalytic resolution of racemic para-nitrostyrene oxide was accomplished by employing the epoxide hydrolases from the whole cells of several Aspergillus niger (A. niger) strains. In the cases investigated, excellent selectivity was achieved with such strains as A, niger 5450, A. niger 5320.

  18. Endopolygalacturonase and pectinesterase from Aspergillus Niger

    Directory of Open Access Journals (Sweden)

    Adriana Lozano Química

    2011-12-01

    Full Text Available Endo-polymethylgalacturonase (endo-PMG EC 3.2.1.41 was produced by submerged fermentation using a local Aspergillus niger strain's Aspergillus niger spores (1xl05 spores/ml medium as inoculum. The only carbon source present in the fermentation medium was commercial citrus pectin. The enzyme was partially purified by precipitation with 20% ammonium sulphate, followed by chromatography in Sephadex G-75 and DEAE Sephadex A-50 columns. Pectinesterase yield was low in those fermentation conditions used. Fermentation crude extract presented two pH values (endo-PMG optimum pH 4.5 and 6.3. The enzymes were stable at pH values between 2.0 and 10.0. Optimum temperature was in the 40°C-45°C range. Enzymes became totally inactive at 70°C. It was also found that sodium ion concentrations greater than 0.1M inhibited endo-PMG. 

  19. 黑曲霉Aspergillus niger P-6021浆态发酵常山胡柚皮渣产果胶霉%Pectinase Production by Aspergillus Niger P-6021 on Citrus Changshan-huyou Peel in Slurry-state Fermentation

    Institute of Scientific and Technical Information of China (English)

    钟卫鸿; 岑沛霖

    2005-01-01

    The peel of Citrus changshan-huyou, coupled with wheat bran, could be utilized by Aspergillus niger P-6021 in slurry-state fermentation to produce pectinase with suitable enzyme composition for application in apple juice processing. The production of pectinase is improved by additional nitrogen source substances and mineral supplements. The ratio of carbon source substances to nitrogen source substances in the medium also has significant effect on the pectinase production by A. niger P-6021 in slurry-state fermentation. In the optimized medium 30℃. The crude pectinase shows significant effect to improve the yield and clarification of apple juice.

  20. SCREENING AND OPTIMIZATION OF CULTURE CONDITIONS FOR CELLULASE PRODUCTION BY ASPERGILLUS NIGER NSPR012 IN SUBMERGED FERMENTATION

    Directory of Open Access Journals (Sweden)

    Juliet Bamidele Akinyele

    2014-12-01

    Full Text Available This study aimed at screening of selected fungal strains and optimization of process parameters for cellulases production in submerged fermentation. Aspergillus niger NSPR012 was selected for further studies as the most potent in producing cellulase of high activity. Utilization of various agro-wastes as substitute tocarboxy methyl cellulose (CMC for cellulase production was also investigated. Among tested carbon sources, banana peels at a concentration of 5% was found to be the most effective carbon source. The cellulase production by Aspergillus niger NSPR012 in mineral salt medium attained maximum after 96 h of incubation. Maximum cellulase activity (0.466µmol/min/mL was obtained with locust beans as the best organic nitrogen source. The optimum incubation temperature and initial pH were 37°C and 5.5, respectively. With this information, banana peels could have good biotechnological potential for bio-products formation in which cellulase is one.

  1. Fumonisins in Aspergillus niger: Industrial and food aspects

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Nielsen, Kristian Fog; Mogensen, Jesper

    Introduction: Fumonisins are toxic seconday metabolites from Fusarium verticillioides and other Fusaria, from Tolypocladium and Aspergillus niger 1,2. Being a generalist Aspergillus niger is the workhorse in a very large number of industrial applications, and is also a common contaminant in foods...... produced fumonisins in pure culture, so we tested whether they could produce fumonisins on citric acid production media in shake flasks, and they could indeed produce small amounts of fumonisins. Conclusions: Most strains of Aspergillus niger can produce fumonisins. In order to have entirely safe...

  2. Fumonisin and Ochratoxin Production in Industrial Aspergillus niger Strains

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Larsen, Thomas Ostenfeld; Thrane, Ulf

    2011-01-01

    Aspergillus niger is perhaps the most important fungus used in biotechnology, and is also one of the most commonly encountered fungi contaminating foods and feedstuffs, and occurring in soil and indoor environments. Many of its industrial applications have been given GRAS status (generally regarded...... as safe). However, A. niger has the potential to produce two groups of potentially carcinogenic mycotoxins: fumonisins and ochratoxins. In this study all available industrial and many non-industrial strains of A. niger (180 strains) as well as 228 strains from 17 related black Aspergillus species were...

  3. Reconstruction of the central carbon metabolism of Aspergillus niger

    DEFF Research Database (Denmark)

    David, Helga; Åkesson, Mats Fredrik; Nielsen, Jens

    2003-01-01

    The topology of central carbon metabolism of Aspergillus niger was identified and the metabolic network reconstructed, by integrating genomic, biochemical and physiological information available for this microorganism and other related fungi. The reconstructed network may serve as a valuable...

  4. Reconstruction of the central carbon metabolism of Aspergillus niger

    DEFF Research Database (Denmark)

    David, Helga; Åkesson, Mats Fredrik; Nielsen, Jens

    2003-01-01

    The topology of central carbon metabolism of Aspergillus niger was identified and the metabolic network reconstructed, by integrating genomic, biochemical and physiological information available for this microorganism and other related fungi. The reconstructed network may serve as a valuable...

  5. Contribution of arginase to manganese metabolism of Aspergillus niger.

    Science.gov (United States)

    Keni, Sarita; Punekar, Narayan S

    2016-02-01

    Aspects of manganese metabolism during normal and acidogenic growth of Aspergillus niger were explored. Arginase from this fungus was a Mn[II]-enzyme. The contribution of the arginase protein towards A. niger manganese metabolism was investigated using arginase knockout (D-42) and arginase over-expressing (ΔXCA-29) strains of A. niger NCIM 565. The Mn[II] contents of various mycelial fractions were found in the order: D-42 strain niger mycelia harvested from acidogenic growth media contain substantially less Mn[II] as compared to those from normal growth media. Nevertheless, acidogenic mycelia harbor considerable Mn[II] levels and a functional arginase. Altered levels of mycelial arginase protein did not significantly influence citric acid production. The relevance of arginase to cellular Mn[II] pool and homeostasis was evaluated and the results suggest that arginase regulation could occur via manganese availability.

  6. Aspergillus niger contains the cryptic phylogenetic species A. awamori

    DEFF Research Database (Denmark)

    Perrone, Giancarlo; Stea, Gaetano; Epifani, Filomena

    2011-01-01

    Aspergillus section Nigri is an important group of species for food and medical mycology, and biotechnology. The Aspergillus niger ‘aggregate’ represents its most complicated taxonomic subgroup containing eight morphologically indistinguishable taxa: A. niger, Aspergillus tubingensis, Aspergillus...... acidus, Aspergillus brasiliensis, Aspergillus costaricaensis, Aspergillus lacticoffeatus, Aspergillus piperis, and Aspergillus vadensis. Aspergillus awamori, first described by Nakazawa, has been compared taxonomically with other black aspergilli and recently it has been treated as a synonym of A. niger....... Phylogenetic analyses of sequences generated from portions of three genes coding for the proteins β-tubulin (benA), calmodulin (CaM), and the translation elongation factor-1 alpha (TEF-1α) of a population of A. niger strains isolated from grapes in Europe revealed the presence of a cryptic phylogenetic species...

  7. cellulase and pectinase production potentials of aspergillus niger ...

    African Journals Online (AJOL)

    Prof Oyeleke

    Production of pectinase and cellulase by Aspergillus niger from corn cob was examined. The organism was ... Besides, corncob causes waste disposal problems since they are being .... coffee, pulp and paper and pharmaceutical industries.

  8. Determinants Of Agricultural Credit Supply To Farmers In The Niger ...

    African Journals Online (AJOL)

    Determinants Of Agricultural Credit Supply To Farmers In The Niger Delta Area Of Nigeria. ... Journal of Agriculture and Social Research (JASR) ... interest rate, availability of credit, loan transaction costs, and level of risk bearing. Results show ...

  9. Environmental Law and Underdevelopment in the Niger Delta ...

    African Journals Online (AJOL)

    User

    the responsibilities of protecting the environment against pollution and ... natural and human surroundings and activities including; biophysical ..... enforcement and security, minority rights, resource allocation and poverty alleviation. The Niger ...

  10. Water Quality Assessment of River Areba, Niger Delta, Nigeria ...

    African Journals Online (AJOL)

    Water Quality Assessment of River Areba, Niger Delta, Nigeria Using Physical ... phosphate (0.78mg/l) were above World Health Organization limits for drinking water. Seasonally, water temperatures, total dissolved solids, biological oxygen ...

  11. Hypertension in a Rural Community in Rivers State, Niger Delta ...

    African Journals Online (AJOL)

    Hypertension in a Rural Community in Rivers State, Niger Delta Region of Nigeria: ... (SSA), is now a serious endemic threat and an important public health issue. ... Medical history such as prior knowledge of blood pressure status and family ...

  12. Pectinolytic complex production by Aspergillus niger URM 4645 ...

    African Journals Online (AJOL)

    SAM

    2014-08-06

    Aug 6, 2014 ... the pectinolytic complex comprising PG (endo- and exo-. PG), PL, and PE by A. niger ... Experimental design and statistical analysis. The influence of ...... Phutela U, Dhuna V, Sandhu S, Chadha BS (2005). Pectinase and.

  13. Descriptive models, grade-tonnage relations, and databases for the assessment of sediment-hosted copper deposits: with emphasis on deposits in the Central Africa Copperbelt, Democratic Republic of the Congo and Zambia: Chapter J in Global mineral resource assessment

    Science.gov (United States)

    Taylor, Cliff D.; Causey, J. Douglas; Denning, Paul D.; Hammarstrom, Jane M.; Hayes, Timothy S.; Horton, John D.; Kirschbaum, Michael J.; Parks, Heather L.; Wilson, Anna B.; Wintzer, Niki E.; Zientek, Michael L.

    2013-01-01

    The Central African Copperbelt (CACB) is one of the most important copper-producing regions of the world. The majority of copper produced in Africa comes from this region defined by the Neoproterozoic Katanga sedimentary basin of the southern Democratic Republic of the Congo (DRC) and northern Zambia. Copper in the CACB is mined from sediment-hosted stratabound copper deposits associated with red beds and includes the giant deposits in the Kolwezi and Tenge-Fungurume districts in the DRC and the Konkola-Musoshi and Nchanga-Chingola districts in Zambia. In recent years, sediment-hosted structurally controlled replacement and vein (SCRV) copper deposits, such as the giant Kansanshi deposit in Zambia have become important exploration targets in the CACB region.

  14. Mapping the polysaccharide degradation potential of Aspergillus niger

    DEFF Research Database (Denmark)

    Andersen, Mikael Rørdam; Giese, Malene; de Vries, Ronald P.

    2012-01-01

    of 188 genes coding for carbohydrate-active enzymes from Aspergillus niger, thus forming an analysis framework, which can be queried. Combination of this information network with gene expression analysis on mono-and polysaccharide substrates has allowed elucidation of concerted gene expression from...... of carbohydrate-active enzymes. Applying this network-based approach, we provide the first genome-scale characterization of all genes coding for carbohydrate-active enzymes identified in A. niger....

  15. Central Asian Republic Info

    Data.gov (United States)

    US Agency for International Development — CAR Info is designed and managed by the Central Asian Republic Mission to fill in the knowledge and reporting gaps in existing agency systems for that Mission. It...

  16. Chemical mimicking of bio-assisted aluminium extraction by Aspergillus niger's exometabolites.

    Science.gov (United States)

    Boriová, Katarína; Urík, Martin; Bujdoš, Marek; Pifková, Ivana; Matúš, Peter

    2016-11-01

    Presence of microorganisms in soils strongly affects mobility of metals. This fact is often excluded when mobile metal fraction in soil is studied using extraction procedures. Thus, the first objective of this paper was to evaluate strain Aspergillus niger's exometabolites contribution on aluminium mobilization. Fungal exudates collected in various time intervals during cultivation were analyzed and used for two-step bio-assisted extraction of alumina and gibbsite. Oxalic, citric and gluconic acids were identified in collected culture media with concentrations up to 68.4, 2.0 and 16.5 mmol L(-1), respectively. These exometabolites proved to be the most efficient agents in mobile aluminium fraction extraction with aluminium extraction efficiency reaching almost 2.2%. However, fungal cultivation is time demanding process. Therefore, the second objective was to simplify acquisition of equally efficient extracting agent by chemically mimicking composition of main organic acid components of fungal exudates. This was successfully achieved with organic acids mixture prepared according to medium composition collected on the 12th day of Aspergillus niger cultivation. This mixture extracted similar amounts of aluminium from alumina compared to culture medium. The aluminium extraction efficiency from gibbsite by organic acids mixture was lesser than 0.09% which is most likely because of more rigid mineral structure of gibbsite compared to alumina. The prepared organic acid mixture was then successfully applied for aluminium extraction from soil samples and compared to standard single step extraction techniques. This showed there is at least 2.9 times higher content of mobile aluminium fraction in soils than it was previously considered, if contribution of microbial metabolites is considered in extraction procedures. Thus, our contribution highlights the significance of fungal metabolites in aluminium extraction from environmental samples, but it also simplifies the

  17. Holocene Paleoecology of the Western Tenere Desert, Niger, Africa

    Science.gov (United States)

    Sereno, P. C.; Caran, S. C.; Housh, T. B.

    2007-12-01

    Multiple paleontological, sedimentological, and isotopic/ionic geochemical indicators permit reconstruction of the Holocene ecology of the western Tenere Desert (southern Sahara hyper-desert). Modern precipitation is highly erratic, averaging 25 mm yearly, and vegetative cover is negligible. From the early to middle Holocene, however, grassland-shrublands and seasonal to permanent lakes and wetlands predominated, supporting diverse limnic, riparian, and upland communities. Annual precipitation probably was comparable to that of the modern southern Sahel, exceeding 350 mm. Coarse-grained sediment washed into the large lacustrine basin from exposures of metamorphic, plutonic, and volcanic rocks in the nearby Air Massif highland. Lake margins fluctuated in response to runoff and limited ground-water discharge. The water was non-saline and there is no evidence of evaporite deposition. Aquatic and riparian macrophytes thrived, as did an extensive lacustrine-palustrine macrofauna. A Sahelian flora of mixed grasses, thorn shrubs, and perhaps some larger woodland species occupied the contiguous uplands, supporting resident and migratory mammalian and avian faunas. Lake levels were high until 6300 to 5200 BP, possibly as late as 4800 BP locally. Deflation of lacustrine deposits during a subsequent dry period provided finer-grained eolian sediment accreting as proximal dunes. The composition of mineral sediment within the middle to late Holocene dunes is different from, but clearly a subset of the lacustrine deposits. Organic matter reworked from the lake sediment was deposited in the dunes and oxidized in situ, generating CO2 that dissolved in soil moisture, producing bicarbonate. The bicarbonate reacted with calcium from weathered minerals, producing calcic cementation about 5100 BP. The resulting petrocalcic horizon was later exposed, weathered, and colonized by sparse terrestrial vegetation for one or more brief periods. A late phase of pedogenesis concurrent with or

  18. Mineral potential for sediment-hosted copper deposits in the Islamic Republic of Mauritania (phase V, deliverable 75): Chapter K in Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)

    Science.gov (United States)

    Taylor, Cliff D.; Giles, Stuart A.

    2015-01-01

    The presence of Neoproterozoic through Cambrian, continental, siliciclastic sedimentary rocks interbedded with dolomitic carbonates, shales, and glacial tillites similar to the Katanga Supergroup host rocks of the Central African Copperbelt and other sediment-hosted copper-bearing Proterozoic sequences worldwide, is first order criteria for consideration of the Neoproterozoic units of the Taoudeni Basin in Mauritania as prospective for sediment-hosted copper deposits. Review of the National Mineral Occurrences Database (Marsh and Anderson, 2015) and previous literature suggest that only a handful of small sediment-hosted copper occurrences have been found to date in Mauritania and that the resource potential for this deposit type is low. In the northern Taoudeni Basin, the most important occurrence is at Taradent. This occurrence consists of three mineralized horizons in the lower Neoproterozoic Char Group in three outcrop areas separated by alluvium over a strike length of 12 kilometers (km). The most extensively mineralized horizon consists of malachite and disseminated copper sulfides, and is concentrated at the base of a dolomitic interval, consistent with a reduced faciestype sediment-hosted copper deposit model. Additional and poorly described copper occurrences in the Taoudeni Basin margin sedimentary rocks in northeastern Mauritania, such as Chegga Guettatira and Sidi Bara, may be sediment-hosted copper occurrences and extend the potential throughout this portion of the Basin.

  19. Country experience in organizing for quality: Niger.

    Science.gov (United States)

    Marquez, L; Madubuike, C

    1999-01-01

    This article describes the efforts of Niger's Ministry of Health Tahoua Quality Assurance Project (QAP) since 1994. QAP aims to improve the delivery of critical primary health care (PHC) services by integrating and institutionalizing the QA approach in the PHC system in 1 demonstration site (Tahoua) and eventually, countrywide. The QAP selected 8 clinical interventions in its package of minimum services. The QAP project provided training, clarified and communicated clinical and management standards, and monitored and initiated a process for preventing and correcting problems. During 1994-96, QAP collaborated with BASICS to assist all 7 District Health Management Teams (DHMTs) in developing data collection tools for rapid performance assessments of the Integrated Management of Childhood Illnesses program. The pilot program proved that measurable gains in QA were possible, even with limited resources. DHMTs will have oversight of QA activities. A special unit within the MOH is not yet fully staffed. The central strategy has been to train teams of health staff at the regional and district level. A multilevel team developed manuals for norms and standards for vaccinations and for managerial operating procedures. The Quality Council redesigned the supervision system. Performance is monitored at quarterly regional and district meetings. A quarterly bulletin is the main dissemination tool. The loss of USAID support led to the loss of technical support from the QAP. The MOH is committed to QA and plans to institutionalize the process. The World Bank and UNICEF agreed to support QA projects in 1999.

  20. Morphology of sympathetic chain in Saguinus niger

    Directory of Open Access Journals (Sweden)

    MARINA P.E. PINTO

    2013-03-01

    Full Text Available Saguinus niger popularly known as Sauim, is a Brazilian North primate. Sympathetic chain investigation would support traumatic and/or cancer diagnosis which are little described in wild animals. The aim of this study was to describe the morphology and distribution of sympathetic chain in order to supply knowledge for neurocomparative research. Three female young animals that came death by natural causes were investigated. Animals were fixed in formaldehyde 10% and dissected along the sympathetic chain in neck, thorax and abdomen. Cranial cervical ganglion was located at the level of carotid bifurcation, related to carotid internal artery. In neck basis the vagosympathetic trunk divides into the sympathetic trunk and the parasympathetic vagal nerve. Sympathetic trunk ran in dorsal position and originated the stellate ganglia, formed by the fusion of caudal cervical and first thoracic ganglia. Vagal trunk laid ventrally to heart and formed the cardiac plexus. In abdomen, on the right side, were found the celiac ganglion and cranial mesenteric ganglion; in the left side these ganglia were fusioned into the celiac-mesenteric ganglion displaced closely to the celiac artery. In both sides, the caudal mesenteric ganglion was located near to the caudal mesenteric artery.

  1. An outbreak of dermatophilosis in sable Hippotragus niger and roan Hippotragus equinus in the Kruger National Park

    Directory of Open Access Journals (Sweden)

    V. de Vos

    1976-08-01

    Full Text Available A severe skin disease diagnosed as dermatophilosis took on alarming proportions in roan antelope Hippotragus equinus and sable antelope Hippotragus niger herds, which were kept in a 256 ha enclosure in the Kruger National Park, Republic of South Africa. Only calves were effected. Numerous Dermatophilus organisms were identified in skin biopsies taken from affected areas and examined histologically. Complete recovery followed a single treatment of intramuscular injections of a combination of a long-acting penicillin and streptomycin and the topical application of a preparation which included copper sulphate and benzene hexachloride. Factors which probably contributed to the outbreak included prolonged wetness, flies, a high density of susceptible animals and playful butting behaviour of the calves. This is the first report of the occurrence of dermatophilosis as a disease entity in wildlife species in southern Africa.

  2. Thermal waters of the Yemen Arab Republic

    Energy Technology Data Exchange (ETDEWEB)

    Dowgiallo, J.

    1986-01-01

    Thermal waters (30-61/sup 0/C) occur in springs and shallow drill-holes (max. 300 m) in several areas of the Yemen Arab Republic. Their mineral content is generally low ( < 1000-2000 ppm TDS) except for waters with high CO/sub 2/ content and those directly influenced by the evaporitic Baid formation (Tertiary) in the Western Lowlands along the Red Sea. The temperature anomalies occur in areas of Quaternary basaltic volcanism (Aden formation) and in fault zones connected with the eastern margin of the Red Sea graben. In the latter zones radiogenic heat may be contributed by Tertiary granitic intrusions.

  3. Identification of thermostable beta-xylosidase activities produced by Aspergillus brasiliensis and Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Mads; Lauritzen, H.K.; Frisvad, Jens Christian

    2007-01-01

    Twenty Aspergillus strains were evaluated for production of extracellular cellulolytic and xylanolytic activities. Aspergillus brasiliensis, A. niger and A. japonicus produced the highest xylanase activities with the A. brasiliensis and A. niger strains producing thermostable beta...

  4. Identification of thermostable beta-xylosidase activities produced by Aspergillus brasiliensis and Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Mads; Lauritzen, H.K.; Frisvad, Jens Christian

    2007-01-01

    Twenty Aspergillus strains were evaluated for production of extracellular cellulolytic and xylanolytic activities. Aspergillus brasiliensis, A. niger and A. japonicus produced the highest xylanase activities with the A. brasiliensis and A. niger strains producing thermostable beta...

  5. Identification of thermostable β-xylosidase activities produced by Aspergillus brasiliensis and Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Mads; Lauritzen, Henrik Klitgaard; Frisvad, Jens Christian

    2007-01-01

    Twenty Aspergillus strains were evaluated for production of extracellular cellulolytic and xylanolytic activities. Aspergillus brasiliensis, A. niger and A. japonicus produced the highest xylanase activities with the A. brasiliensis and A. niger strains producing thermostable beta...

  6. Strategies for Mitigation of Flood Risk in the Niger Delta, Nigeria ...

    African Journals Online (AJOL)

    Strategies for Mitigation of Flood Risk in the Niger Delta, Nigeria. ... the Niger Delta, there is need for establishment of coastal management zone authority, land-use ... building codes, flood forecasting and warning systems, flood insurance and ...

  7. Mineral potential for volcanogenic massive sulfide deposits in the Islamic Republic of Mauritania, (phase V, deliverable 77): Chapter L in Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)

    Science.gov (United States)

    Taylor, Cliff D.; Giles, Stuart A.

    2015-01-01

    Potential for base- and precious-metal-bearing volcanogenic massive sulfide deposits (VMS) exists in Mauritania in the greenstone belts of the southwestern Rgueïbat Shield and in the allochthonous portions of the central and southern Mauritanides. Additional potential exists for VMS deposits within the Tiris Complex of the central Rgueïbat Shield. Volcanosedimentary successions of Paleoproterozoic rocks of the northeastern portion of the Rgueïbat Shield are also permissive for volcanogenic massive sulfide deposits. These types of mineral occurrences are common features of marine volcanosedimentary successions worldwide and can be of almost any age, although Proterozoic examples are less abundant.

  8. Aspergillus niger contains the cryptic phylogenetic species A. awamori.

    Science.gov (United States)

    Perrone, Giancarlo; Stea, Gaetano; Epifani, Filomena; Varga, János; Frisvad, Jens C; Samson, Robert A

    2011-11-01

    Aspergillus section Nigri is an important group of species for food and medical mycology, and biotechnology. The Aspergillus niger 'aggregate' represents its most complicated taxonomic subgroup containing eight morphologically indistinguishable taxa: A. niger, Aspergillus tubingensis, Aspergillus acidus, Aspergillus brasiliensis, Aspergillus costaricaensis, Aspergillus lacticoffeatus, Aspergillus piperis, and Aspergillus vadensis. Aspergillus awamori, first described by Nakazawa, has been compared taxonomically with other black aspergilli and recently it has been treated as a synonym of A. niger. Phylogenetic analyses of sequences generated from portions of three genes coding for the proteins β-tubulin (benA), calmodulin (CaM), and the translation elongation factor-1 alpha (TEF-1α) of a population of A. niger strains isolated from grapes in Europe revealed the presence of a cryptic phylogenetic species within this population, A. awamori. Morphological, physiological, ecological and chemical data overlap occurred between A. niger and the cryptic A. awamori, however the splitting of these two species was also supported by AFLP analysis of the full genome. Isolates in both phylospecies can produce the mycotoxins ochratoxin A and fumonisin B₂, and they also share the production of pyranonigrin A, tensidol B, funalenone, malformins, and naphtho-γ-pyrones. In addition, sequence analysis of four putative A. awamori strains from Japan, used in the koji industrial fermentation, revealed that none of these strains belong to the A. awamori phylospecies.

  9. Transcriptome analysis of Aspergillus niger grown on sugarcane bagasse

    Directory of Open Access Journals (Sweden)

    Goldman Gustavo H

    2011-10-01

    Full Text Available Abstract Background Considering that the costs of cellulases and hemicellulases contribute substantially to the price of bioethanol, new studies aimed at understanding and improving cellulase efficiency and productivity are of paramount importance. Aspergillus niger has been shown to produce a wide spectrum of polysaccharide hydrolytic enzymes. To understand how to improve enzymatic cocktails that can hydrolyze pretreated sugarcane bagasse, we used a genomics approach to investigate which genes and pathways are transcriptionally modulated during growth of A. niger on steam-exploded sugarcane bagasse (SEB. Results Herein we report the main cellulase- and hemicellulase-encoding genes with increased expression during growth on SEB. We also sought to determine whether the mRNA accumulation of several SEB-induced genes encoding putative transporters is induced by xylose and dependent on glucose. We identified 18 (58% of A. niger predicted cellulases and 21 (58% of A. niger predicted hemicellulases cellulase- and hemicellulase-encoding genes, respectively, that were highly expressed during growth on SEB. Conclusions Degradation of sugarcane bagasse requires production of many different enzymes which are regulated by the type and complexity of the available substrate. Our presently reported work opens new possibilities for understanding sugarcane biomass saccharification by A. niger hydrolases and for the construction of more efficient enzymatic cocktails for second-generation bioethanol.

  10. Electrochemical monitoring of citric acid production by Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Kutyła-Olesiuk, Anna; Wawrzyniak, Urszula E.; Ciosek, Patrycja; Wróblewski, Wojciech, E-mail: wuwu@ch.pw.edu.pl

    2014-05-01

    Highlights: • Citric acid fermentation process (production) by Aspergillus niger. • Qualitative/quantitative monitoring of standard culture and culture infected with yeast. • Electronic tongue based on potentiometric and voltammetric sensors. • Evaluation of the progress and the correctness of the fermentation process. • The highest classification abilities of the hybrid electronic tongue. - Abstract: Hybrid electronic tongue was developed for the monitoring of citric acid production by Aspergillus niger. The system based on various potentiometric/voltammetric sensors and appropriate chemometric techniques provided correct qualitative and quantitative classification of the samples collected during standard Aspergillus niger culture and culture infected with yeast. The performance of the proposed approach was compared with the monitoring of the fermentation process carried out using classical methods. The results obtained proved, that the designed hybrid electronic tongue was able to evaluate the progress and correctness of the fermentation process.

  11. Phosphate solubilizing ability of two Arctic Aspergillus niger strains

    Directory of Open Access Journals (Sweden)

    Shiv Mohan Singh,

    2011-06-01

    Full Text Available Many filamentous fungi were isolated from the soils of Ny-Ålesund, Spitsbergen, Svalbard, and were screened in vitro for their phosphate solubilizing ability. Two strains of Aspergillus niger showed good tricalcium phosphate (TCP solubilizing ability in Pikovskaya's medium. The TCP solubilization index was calculated at varying levels of pH and temperatures. The ability of Aspergillus niger strain-1 to solubilize and release inorganic-P was 285 µg ml–1, while Aspergillus niger strain-2 solubilized 262 µg ml–1 from 0.5% TCP after seven days. This is the first report of TCP solubilization by Arctic strains that may serve as very good phosphate solubilizers in the form of biofertilizer.

  12. Physiological characterisation of acuB deletion in Aspergillus niger

    DEFF Research Database (Denmark)

    Meijer, Susan Lisette; De Jongh, Willem Adriaan; Olsson, Lisbeth

    2009-01-01

    The acuB gene of Aspergillus niger is an ortholog of facB in Aspergillus nidulans. Under carbon-repression conditions, facB is repressed, thereby preventing acetate metabolism when the repressing carbon source is present. Even though facB is reported to be repressed directly by CreA, it is believed...... that a basal level of FacB activity exists under glucose-repressive conditions. In the present study, the effect of deletion of acuB on the physiology of A. niger was assessed. Differences in organic acid and acetate production, enzyme activities and extracellular amino and non-amino organic acid production...... were determined under glucose-repressing and -derepressing conditions. Furthermore, consumption of alternative carbon sources (e.g. xylose, citrate, lactate and succinate) was investigated. It was shown that AcuB has pleiotropic effects on the physiology of A. niger. The results indicate that metabolic...

  13. Evolution of uranium distribution and speciation in mill tailings, COMINAK Mine, Niger.

    Science.gov (United States)

    Déjeant, Adrien; Galoisy, Laurence; Roy, Régis; Calas, Georges; Boekhout, Flora; Phrommavanh, Vannapha; Descostes, Michael

    2016-03-01

    This study investigated the evolution of uranium distribution and speciation in mill tailings from the COMINAK mine (Niger), in production since 1978. A multi-scale approach was used, which combined high resolution remote sensing imagery, ICP-MS bulk rock analyses, powder X-ray diffraction, Scanning Electron Microscopy, Focused Ion Beam--Transmission Electron Microscopy and X-ray Absorption Near Edge Spectroscopy. Mineralogical analyses showed that some ore minerals, including residual uraninite and coffinite, undergo alteration and dissolution during tailings storage. The migration of uranium and other contaminants depends on (i) the chemical stability of secondary phases and sorbed species (dissolution and desorption processes), and (ii) the mechanical transport of fine particles bearing these elements. Uranium is stabilized after formation of secondary uranyl sulfates and phosphates, and adsorbed complexes on mineral surfaces (e.g. clay minerals). In particular, the stock of insoluble uranyl phosphates increases with time, thus contributing to the long-term stabilization of uranium. At the surface, a sulfate-cemented duricrust is formed after evaporation of pore water. This duricrust limits water infiltration and dust aerial dispersion, though it is enriched in uranium and many other elements, because of pore water rising from underlying levels by capillary action. Satellite images provided a detailed description of the tailings pile over time and allow monitoring of the chronology of successive tailings deposits. Satellite images suggest that uranium anomalies that occur at deep levels in the pile are most likely former surface duricrusts that have been buried under more recent tailings.

  14. Production of extremophilic bacterial cellulase enzymes in aspergillus niger.

    Energy Technology Data Exchange (ETDEWEB)

    Gladden, John Michael

    2013-09-01

    Enzymes can be used to catalyze a myriad of chemical reactions and are a cornerstone in the biotechnology industry. Enzymes have a wide range of uses, ranging from medicine with the production of pharmaceuticals to energy were they are applied to biofuel production. However, it is difficult to produce large quantities of enzymes, especially if they are non-native to the production host. Fortunately, filamentous fungi, such as Aspergillus niger, are broadly used in industry and show great potential for use a heterologous enzyme production hosts. Here, we present work outlining an effort to engineer A. niger to produce thermophilic bacterial cellulases relevant to lignocellulosic biofuel production.

  15. Expression and secretion of Aspergillus niger glucoamylase in Saccharomyces cerevisiae

    Institute of Scientific and Technical Information of China (English)

    李文清; 何鸣; 罗进贤

    1995-01-01

    Aspergillus niger glucoamylase GA 1 cDNA was inserted in between the yeast PGK promoter and terminator on plasmid pMA91. The resultant plasmid pMAG69 was introduced into Saccharomyces cerevisiae GRF18 by protoplast transformation. The A niger GA I cDNA was expressed efficiently under the contiol of PGK promoter and 99% of the gene products were secreted into the culture medium using its own signal sequence The recombmant yeast can digest 87% of starch in 2 d in the medium containing 10% starch. The recombinant plasmid pMAG69 can exist stably in 5. cerevisiae.

  16. Electrochemical monitoring of citric acid production by Aspergillus niger.

    Science.gov (United States)

    Kutyła-Olesiuk, Anna; Wawrzyniak, Urszula E; Ciosek, Patrycja; Wróblewski, Wojciech

    2014-05-01

    Hybrid electronic tongue was developed for the monitoring of citric acid production by Aspergillus niger. The system based on various potentiometric/voltammetric sensors and appropriate chemometric techniques provided correct qualitative and quantitative classification of the samples collected during standard Aspergillus niger culture and culture infected with yeast. The performance of the proposed approach was compared with the monitoring of the fermentation process carried out using classical methods. The results obtained proved, that the designed hybrid electronic tongue was able to evaluate the progress and correctness of the fermentation process.

  17. Mineral oils

    Science.gov (United States)

    Furby, N. W.

    1973-01-01

    The characteristics of lubricants made from mineral oils are discussed. Types and compositions of base stocks are reviewed and the product demands and compositions of typical products are outlined. Processes for commercial production of mineral oils are examined. Tables of data are included to show examples of product types and requirements. A chemical analysis of three types of mineral oils is reported.

  18. Functional properties, nutritional value, and industrial applications of Niger Oilseeds (Guizotia abyssinica Cass.).

    Science.gov (United States)

    Ramadan, Mohamed Fawzy

    2012-01-01

    Non-conventional seeds are being considered as novel food because their constituents have unique chemical properties and may augment the supply of nutritional and functional products. Niger (Guizotia abyssinica Cass.) seed and its crude oil have been widely used in traditional nutritional and medicinal applications. Consequently, niger seed has been extensively studied for its nutritional value, biological activities, and antioxidative properties. In consideration of their potential utilization, detailed knowledge on the composition of niger oilseeds is of major importance. The diversity of applications to which niger seed can be put gives this oilseed great industrial importance. This review summarizes the nutritional value, functional properties, and industrical applications of niger seeds.

  19. Influence of groundwater on the degradation of irrigated soils in a semi-arid region, the inner delta of the Niger River, Mali

    Science.gov (United States)

    Valenza, A.; Grillot, J. C.; Dazy, J.

    2000-08-01

    The problem of soil degradation through alkalinization/salinization in an irrigated area with a semi-arid climate was examined in the inner delta of the Niger River, Mali, by the study of groundwater hydraulics and hydrochemistry in an area recharged by irrigation water. On the basis of data analysis on various scales, it is concluded that the current extent of the surface saline soils is due to a combination of three factors: (1) the existence of ancient saline soils (solonchaks) resulting from the creation of a broad sabkha west of the former course of the Niger River, now called the Fala of Molodo. These saline crusts were gradually deposited during the eastward tilting of the tectonic block that supports the Niger River; (2) the irrigation processes during the recent reflooding of the Fala of Molodo (river diversion in 1950). These used very poorly mineralized surface water but reintroduced into the alluvial groundwater system - generally of a low permeability (K=10-6 m s-1) - salts derived from the ancient solonchaks; and (3) the redeposition of the dissolved salts on the surface due to the intense evapotranspiration linked to the present Sahelian climate. In this context, only efficient artificial draining of subsurface alluvial groundwater can eliminate most of the highly mineralized flow and thus reduce the current saline deposits.

  20. Central African Republic.

    Science.gov (United States)

    1986-02-01

    Focus in this discussion of the Central African Republic is on: geography; the people; history and political conditions; government; the economy; foreign relations; and relations with the US. The population of the Central African Republic totaled 2.7 million in 1985 with an annual growth rate of 2.8%. The infant mortality rate is 134/1000 with life expectancy at 49 years. The Central African Republic is at almost the precise center of Africa, about 640 km from the nearest ocean. More than 70% of the population live in rural areas. There are more than 80 ethnic groups, each with its own language. The precolonial history of the area was marked by successive waves of migration, of which little is known. These migrations are responsible for the complex ethnic and linguistic patterns today. United with Chad in 1906, it formed the Oubangui-Chari-Chad colony. In 1910, it became 1 of the 4 territories of the Federation of French Equatorial Africa, along with Chad, Congo, and Gabon. After World War II, the French Constitution of 1946 inaugurated the first of a series of reforms that led eventually to complete independence for all French territories in western and equatorial Africa. The nation became an autonomous republic within the newly established French Community on December 1, 1958, and acceded to complete independence as the Central Africa Republic on August 13, 1960. The government is made up of the executive and the judicial branches. The constitution and legislature remain suspended. All executive and legislative powers, as well as judicial oversight, are vested in the chief of state. The Central African Republic is 1 of the world's least developed countries, with an annual per capita income of $310. 85% of the population is engaged in subsistence farming. Diamonds account for nearly 1/3 of export earnings; the industrial sector is limited. The US terminated bilateral assistance programs in 1979, due to the human rights violations of the Bokassa regime, but modest

  1. Carbon starvation in the filamentous fungus Aspergillus niger

    NARCIS (Netherlands)

    Nitsche, Benjamin Manuel

    2012-01-01

    This study investigated carbon starvation in the filamentous fungus Aspergillus niger during submerged cultivation in bioreactor batch cultures. The work described in this thesis can be discussed as follows: (I) Establishment of computational resources for omics data analysis and interpretation in c

  2. Biotransformation of quinazoline and phthalazine by Aspergillus niger.

    Science.gov (United States)

    Sutherland, John B; Heinze, Thomas M; Schnackenberg, Laura K; Freeman, James P; Williams, Anna J

    2011-03-01

    Cultures of Aspergillus niger NRRL-599 in fluid Sabouraud medium were grown with quinazoline and phthalazine for 7 days. Metabolites were purified by high-performance liquid chromatography and identified by mass spectrometry and proton nuclear magnetic resonance spectroscopy. Quinazoline was oxidized to 4-quinazolinone and 2,4-quinazolinedione, and phthalazine was oxidized to 1-phthalazinone.

  3. Genetic relationships among strains of the Aspergillus niger aggregate

    DEFF Research Database (Denmark)

    Ferracin, L.M.; Frisvad, Jens Christian; Taniwaki, M.H.

    2009-01-01

    We analyzed the genetic relationships between 51 fungal isolates previously identified as A. niger aggregate, obtained from dried fruit samples from worldwide origin and 7 A. tubingensis obtained from Brazilian coffee beans samples. Greater fungal diversity was found in black sultanas. Aspergillus...

  4. Characterization of four new antifungal yanuthones from Aspergillus niger

    DEFF Research Database (Denmark)

    Petersen, Lene Maj; Holm, Dorte Koefoed; Knudsen, Peter Boldsen

    2015-01-01

    Four new yanuthone analogs (1–4) were isolated from the filamentous fungus Aspergillus niger. The structures of the new compounds were elucidated on the basis of UHPLC-DAD-HRMS data and one-dimensional and two-dimensional NMR spectroscopy. Labeling studies with 13C8-6-methylsalicylic acid...

  5. Enhanced citrate production through gene insertion in Aspergillus niger

    DEFF Research Database (Denmark)

    Jongh, Wian de; Nielsen, Jens

    2007-01-01

    The effect of inserting genes involved in the reductive branch of the tricarboxylic acid (TCA) cycle on citrate production by Aspergillus niger was evaluated. Several different genes were inserted individually and in combination, i.e. malate dehydrogenase (mdh2) from Saccharomyces cerevisiae, two...

  6. Traditional chiefs and modern land tenure law in Niger

    NARCIS (Netherlands)

    Lund, C.; Hesseling, G.S.C.M.; Rouveroy van Nieuwaal, van E.; Dijk, van R.A.

    1999-01-01

    Many local tenure arrangements in Niger were largely implicit, not recorded in any codified form. In the process of codification now underway, chiefs are regarded as the key interpreters of tradition, mutating the implicit into the explicit. Land tenure reform is not without contradictions. How are

  7. Aminopeptidase C of Aspergillus niger is a Novel Phenylalanine Aminopeptidase

    NARCIS (Netherlands)

    Basten, E.J.W.; Dekker, P.J.T.; Schaap, P.J.

    2003-01-01

    A novel enzyme with a specific phenylalanine aminopeptidase activity (ApsC) from Aspergillus niger (CBS 120.49) has been characterized. The derived amino acid sequence is not similar to any previously characterized aminopeptidase sequence but does share similarity with some mammalian acyl-peptide hy

  8. Studies on the production of fungal peroxidases in Aspergillus niger

    NARCIS (Netherlands)

    Conesa, A.; Hondel, C.A.M.J.J. van den; Punt, P.J.

    2000-01-01

    To get insight into the limiting factors existing for the efficient production of fungal peroxidase in filamentous fungi, the expression of the Phanerochaete chrysosporium lignin peroxidase H8 (lipA) and manganese peroxidase (MnP) H4 (mnp1) genes in Aspergillus niger has been studied. For this

  9. Studies on the production of fungal peroxidases in Aspergillus niger

    NARCIS (Netherlands)

    Conesa, A.; Hondel, C.A.M.J.J. van den; Punt, P.J.

    2000-01-01

    To get insight into the limiting factors existing for the efficient production of fungal peroxidase in filamentous fungi, the expression of the Phanerochaete chrysosporium lignin peroxidase H8 (lipA) and manganese peroxidase (MnP) H4 (mnp1) genes in Aspergillus niger has been studied. For this purpo

  10. Gluconate formation and polyol metabolism in Aspergillus niger.

    NARCIS (Netherlands)

    Witteveen, C.F.B.

    1993-01-01

    The capacity of A.niger to accumulate metabolites is remarkable. Under all conditions polyols accumulate in the cell and when mycelium in later developmental stages is considered, depending on the carbon source, aeration and external pH, polyols and/or organic acids can be formed in a very efficient

  11. Sawaba's rebellion in Niger (1964-1965) : narrative and meaning

    NARCIS (Netherlands)

    Walraven, van K.; Abbink, J.; Bruijn, de M.E.; Walraven, van K.

    2003-01-01

    One of the least-studied revolts in postcolonial Africa, the invasion of Niger in 1964 by guerrillas of the outlawed Sawaba party, was a dismal failure and culminated in a failed attempt on the life of President Diori in the spring of 1965. Personal aspirations for higher education, access to jobs a

  12. Studies on the production of fungal peroxidases in Aspergillus niger

    NARCIS (Netherlands)

    Conesa, A.; Hondel, C.A.M.J.J. van den; Punt, P.J.

    2000-01-01

    To get insight into the limiting factors existing for the efficient production of fungal peroxidase in filamentous fungi, the expression of the Phanerochaete chrysosporium lignin peroxidase H8 (lipA) and manganese peroxidase (MnP) H4 (mnp1) genes in Aspergillus niger has been studied. For this purpo

  13. Characterization of pectate lyase A from Aspergillus niger

    NARCIS (Netherlands)

    Benen, J.A.E.; Parenicova, L.; Kester, H.C.M.; Visser, J.

    2001-01-01

    The Aspergillus niger plyA gene encoding pectate lyase A (EC 4.2.99.3) was cloned from a chromosomal EMBL4 library using the Aspergillus nidulans pectate lyase encoding gene [Dean, R. A., and Timberlake, W. E. (1989) Plant Cell 1, 275-284] as a probe. The plyA gene was overexpressed using a promoter

  14. Secretion in spatially differentiated colonies of Aspergillus niger

    NARCIS (Netherlands)

    Roelofs, M.S.

    2009-01-01

    A wide variety of enzymes is commonly used in industrial applications, for instance in the food and feed industry. Because of its exceptionally high protein secretion capacity, one of the preferred hosts for the production of such enzymes is the filamentous fungus Aspergillus niger. The research des

  15. The Economic Dimensions of the Niger Delta Ethnic Conflicts (Pp ...

    African Journals Online (AJOL)

    User

    Niger Delta in the sharing of the economic and political benefits of the oil and gas wealth of the .... new dimensions including violent ethnic conflicts and vandalisation of oil installations. .... “animal Farm” and the works on political economy by Karl Marx. These authors in ... potential of violent ethnic conflict. Planners should ...

  16. An annotated list of Fishes from the Niger Delta

    NARCIS (Netherlands)

    Boeseman, M.

    1963-01-01

    At the end of November 1960, the Leiden Museum received an interesting collection of animals, mostly fishes, from the Niger delta. All specimens were collected by Mr. H. J. G. Beets, at the time employed by Shell B.P. — Delta Investigations, during the period May to August 1960, and in the region

  17. Aminopeptidase C of Aspergillus niger is a Novel Phenylalanine Aminopeptidase

    NARCIS (Netherlands)

    Basten, E.J.W.; Dekker, P.J.T.; Schaap, P.J.

    2003-01-01

    A novel enzyme with a specific phenylalanine aminopeptidase activity (ApsC) from Aspergillus niger (CBS 120.49) has been characterized. The derived amino acid sequence is not similar to any previously characterized aminopeptidase sequence but does share similarity with some mammalian acyl-peptide hy

  18. Maturation of conidia on conidiophores of Aspergillus niger

    NARCIS (Netherlands)

    Teertstra, Wieke R.; Tegelaar, Martin; Dijksterhuis, Jan; Golovina, Elena A.; Ohm, Robin A.; Wösten, Han A.B.

    2016-01-01

    Conidia of Aspergillus niger are produced on conidiophores. Here, maturation of conidia on these asexual reproductive structures was studied. Pigmented conidia that had developed on conidiophores for 2, 5, and 8 days were similarly resistant to heat and were metabolically active as shown by CO2 rele

  19. Lipids of marine origin: the rudderfish (Centrolophus niger)

    CSIR Research Space (South Africa)

    De Koning, AJ

    2006-01-01

    Full Text Available Muscle of rudderfish (centrolophus niger), or black ruff, a rare mesopelagic fish caught in the South Atlantic, was found to contain 19.3% total lipids. The major part of the lipids (~70%) was unusual in not yielding glycerol but non...

  20. Oil Politics and Violence in Postcolonial Niger Delta Drama

    African Journals Online (AJOL)

    Prof

    11 (1), S/NO 45, JANUARY, 2017. 171. Copyright © IAARR ... Niger Delta is under socio-economic, political and environmental “terrorism” of the. Federal .... As Koko tells us in Ola Rotimi's Akassa You Mi, “oppressors wax stronger when ...

  1. Dominican Republic; Statistical Appendix

    OpenAIRE

    International Monetary Fund

    2003-01-01

    In this paper, statistical data for the Dominican Republic were presented as real, public, financial, and external sectors. In real sector, GDP by sector at constant prices, savings, investment, consumer price index, petroleum statistics, and so on, were outlined. The public sector summarizes operations of the consolidated public sector, central government, and revenues. A summary of the banking system, claims, interest rates, financial indicators, and reserve requirements were described in t...

  2. Dominican Republic; Statistical Appendix

    OpenAIRE

    International Monetary Fund

    2003-01-01

    In this paper, statistical data for the Dominican Republic were presented as real, public, financial, and external sectors. In real sector, GDP by sector at constant prices, savings, investment, consumer price index, petroleum statistics, and so on, were outlined. The public sector summarizes operations of the consolidated public sector, central government, and revenues. A summary of the banking system, claims, interest rates, financial indicators, and reserve requirements were described in t...

  3. Fumonisin and ochratoxin production in industrial Aspergillus niger strains.

    Directory of Open Access Journals (Sweden)

    Jens C Frisvad

    Full Text Available Aspergillus niger is perhaps the most important fungus used in biotechnology, and is also one of the most commonly encountered fungi contaminating foods and feedstuffs, and occurring in soil and indoor environments. Many of its industrial applications have been given GRAS status (generally regarded as safe. However, A. niger has the potential to produce two groups of potentially carcinogenic mycotoxins: fumonisins and ochratoxins. In this study all available industrial and many non-industrial strains of A. niger (180 strains as well as 228 strains from 17 related black Aspergillus species were examined for mycotoxin production. None of the related 17 species of black Aspergilli produced fumonisins. Fumonisins (B(2, B(4, and B(6 were detected in 81% of A. niger, and ochratoxin A in 17%, while 10% of the strains produced both mycotoxins. Among the industrial strains the same ratios were 83%, 33% and 26% respectively. Some of the most frequently used strains in industry NRRL 337, 3112 and 3122 produced both toxins and several strains used for citric acid production were among the best producers of fumonisins in pure agar culture. Most strains used for other biotechnological processes also produced fumonisins. Strains optimized through random mutagenesis usually maintained their mycotoxin production capability. Toxigenic strains were also able to produce the toxins on media suggested for citric acid production with most of the toxins found in the biomass, thereby questioning the use of the remaining biomass as animal feed. In conclusion it is recommended to use strains of A. niger with inactive or inactivated gene clusters for fumonisins and ochratoxins, or to choose isolates for biotechnological uses in related non-toxigenic species such as A. tubingensis, A. brasiliensis, A vadensis or A. acidus, which neither produce fumonisins nor ochratoxins.

  4. Nigeria. Petroleum, pollution and poverty in the Niger Delta

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-06-15

    The oil industry has operated in the Niger Delta in Nigeria for more than half a century - bringing almost no benefit to the people living there. Instead, widespread and unchecked human rights violations have pushed many people deeper into poverty and deprivation, fuelled conflict and led to a pervasive sense of powerlessness and frustration. This multidimensional crisis is driven by many factors - abuses committed by the security forces and militant groups, extensive pollution of land and water, corruption, serious corporate bad practice and government neglect. Nigeria: Petroleum, pollution and poverty in the Niger Delta focuses on one dimension of the crisis: the impact of pollution and environmental damage caused by the oil industry on the human rights of those living in the Niger Delta. Many people in the oil-producing areas of the delta rely on fisheries, subsistence agriculture and associated processing industries for their livelihood. Decades of pollution and environmental damage have resulted in violations of the right to an adequate standard of living - including food and water - violations of the right to gain a living through work, and violations of the right to health. The report examines who is responsible for this situation in a context where multinational oil companies have been operating for decades. It highlights how companies take advantage of the weak regulatory systems that characterize many poor countries, and how the poorest people are often the most vulnerable to exploitation. The people of the Niger Delta have seen their human rights undermined by oil companies that their government can not - or will not - hold to account. They have been systematically denied access to information about how oil exploration and production will affect them, and are repeatedly denied access to justice. The Niger Delta provides a stark case study of the lack of accountability of a government to the people, and of multinational companies' almost total lack

  5. Cadmium biosorption by Aspergillus niger; Biossorcao de cadmio pelo Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Silva, E.P.; Barros Junior, L.M.; Duarte, M.M.L.; Macedo, G.R. [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil)]. E-mail: edmilson@eq.ufrn.br

    2003-07-01

    Biosorption is a property of certain types of inactive, dead, microbial biomass to bind and concentrate heavy metals from even very dilute aqueous solutions. Biomass exhibits this property, acting just as a chemical substance, as an ion exchanger of biological origin. It is particularly the cell wall structure of certain algae, fungi and bacteria which was found responsible for this phenomenon. Some of the biomass types come as a waste by-product of large-scale industrial fermentations (the mold Rhizopus or the bacterium Bacillus subtilis). Other metal-binding biomass types, certain abundant seaweeds (particularly brown algae e.g. Sargassum, Ecklonia), can be readily collected from the oceans. These biomass types, serving as a basis for metal biosorption processes, can accumulate in excess of 25% of their dry weight in deposited heavy metals: Pb, Cd, U, Cu, Zn, even Cr and others. Sorption experiments using the Aspergillus niger fungus for cadmium removal were carried out to study the factors influencing and optimizing the biosorption of this metal. The effects of pH, time, biomass concentration, and initial concentration of the heavy metal on the rate of metallic biosorption were examined. (author)

  6. Expression of human α1-proteinase inhibitor in Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Punt Peter J

    2007-10-01

    Full Text Available Abstract Background Human α1-proteinase inhibitor (α1-PI, also known as antitrypsin, is the most abundant serine protease inhibitor (serpin in plasma. Its deficiency is associated with development of progressive, ultimately fatal emphysema. Currently in the United States, α1-PI is available for replacement therapy as an FDA licensed plasma-derived (pd product. However, the plasma source itself is limited; moreover, even with efficient viral inactivation steps used in manufacture of plasma products, the risk of contamination from emerging viruses may still exist. Therefore, recombinant α1-PI (r-α1-PI could provide an attractive alternative. Although r-α1-PI has been produced in several hosts, protein stability in vitro and rapid clearance from the circulation have been major issues, primarily due to absent or altered glycosylation. Results We have explored the possibility of expressing the gene for human α1-PI in the filamentous fungus Aspergillus niger (A. niger, a system reported to be capable of providing more "mammalian-like" glycosylation patterns to secretable proteins than commonly used yeast hosts. Our expression strategy was based on fusion of α1-PI with a strongly expressed, secreted leader protein (glucoamylase G2, separated by dibasic processing site (N-V-I-S-K-R that provides in vivo cleavage. SDS-PAGE, Western blot, ELISA, and α1-PI activity assays enabled us to select the transformant(s secreting a biologically active glycosylated r-α1-PI with yields of up to 12 mg/L. Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS analysis further confirmed that molecular mass of the r-α1-PI was similar to that of the pd-α1-PI. In vitro stability of the r-α1-PI from A. niger was tested in comparison with pd-α1-PI reference and non-glycosylated human r-α1-PI from E. coli. Conclusion We examined the suitability of the filamentous fungus A. niger for the expression of the human gene for α1-PI, a medium size

  7. Genetic relationships among strains of the Aspergillus niger aggregate

    Directory of Open Access Journals (Sweden)

    Lara Munique Ferracin

    2009-11-01

    Full Text Available We analyzed the genetic relationships between 51 fungal isolates previously identified as A. niger aggregate, obtained from dried fruit samples from worldwide origin and 7 A. tubingensis obtained from Brazilian coffee beans samples. Greater fungal diversity was found in black sultanas. Aspergillus niger sensu stricto was the most prevalent species. It was found in all fruit substrates of all geographical origins. Based on Random Amplification of Polymorphic DNA (RAPD and β-tubulin sequences data two groups of A. niger were found. In spite of the small number of isolates from Group IV an association between extrolite patterns and molecular clustering is speculated. A. tubingensis were the second most frequent species and this species were clearly subdivided into two groups. The finding of two groups for A. tubingensis strains could not yet explain the contradictions found in the literature about the capability this species for ochratoxin production, because both of them were formed by only non-ochratoxin-producing strains.Neste trabalho foi analisada a relação genética entre 51 isolados obtidos de amostras de frutas secas provenientes de diferentes regiões do previamente identificados como pertencentes ao agregado A. niger e 7 isolados de Aspergillus tubingensis obtidos de amostras de café do Brasil. Maior diversidade fúngica foi encontrada em uvas passas escuras. Aspergillus niger sensu stricto foi a espécie mais frequente. Esta espécie foi encontrada em todos os substratos e origens geográficas analisadas. Baseando-se nos dados de Polimorfismo de DNA Amplificado ao Acaso (RAPD e sequências de nucleotídeos do gene da β-tubulina, dois grupos de A. niger foram observados. Apesar do pequeno número de isolados do grupo IV uma associação entre padrão de extrólitos e agrupamento molecular foi encontrada. A. tubingensis foi a segunda espécie mais frequente e foi claramente subdivida em dois grupos. Como os grupos de A. tubingensis s

  8. Czech Republic : Accounting and Auditing

    OpenAIRE

    World Bank

    2003-01-01

    Financial reporting and auditing requirements in the Czech Republic are currently in transition from complying with national standards to complying with International Accounting Standards (IAS), International Standards on Auditing (ISA), and the European Union (EU) Directives. By law, the Czech Republic seeks to attain maximum compliance with the EU Fourth and Seventh Directives and the E...

  9. The diatom flora in the vicinity of the Pretoria Salt Pan, Transvaal, Republic of South Africa. Part III (final)

    CSIR Research Space (South Africa)

    Schoeman, FR

    1984-03-12

    Full Text Available arising in Diatom taxonomy. mt. J. Math. Educ. Sci. Technol. 12: 121—124. COMPERE, P. 1980. Algues de l’AIr (Niger). Bull, fard. bot. flat. BeIg. 50: 269—329. COMPERE, P. 1981a. Algues des deserts d’Iran. Bull. Jard. bat. nat. Belg. 51: 3—40. COMPERE..., 0001 Republic of South Africa *To whom correspondence should be addressed Introduction The hypersaline Pretoria Salt Pan with its saline artesian spring is the only example of a maar lake in southern Africa. Its morphometry and physico...

  10. Biotransformation of (-)beta-pinene by Aspergillus niger ATCC 9642.

    Science.gov (United States)

    Toniazzo, Geciane; de Oliveira, Débora; Dariva, Cláudio; Oestreicher, Enrique Guillermo; Antunes, Octávio A C

    2005-01-01

    The main objective of this work was to investigate the biotransformations of (-)alpha-pinene, (-)beta-pinene, and (+) limonene by Aspergillus niger ATCC 9642. The culture conditions involved--concentration of cosolvent (EtOH), substrate applied, and sequential addition of substrates were--investigated. Adaptation of the precultures with small amounts of substrate was also studied. The experiments were performed in conical flasks with liquid cultures. This strain of A. niger was able to convert only (-)beta-pinene into alpha-terpineol. An optimum conversion of (-)beta-pinene into alpha-terpineol of about 4% was obtained when the substrate was applied as a diluted solution in EtOH and sequential addition of substrate was used.

  11. Biosorption of cadmium using the fungus Aspergillus niger

    Directory of Open Access Journals (Sweden)

    L.M. Barros Júnior

    2003-09-01

    Full Text Available Sorption experiments using the Aspergillus niger fungus for cadmium removal were carried out to study the factors influencing and optimizing the biosorption of this metal. The effects of pH, time, biomass concentration, and initial concentration of the heavy metal on the rate of metallic biosorption were examined. An experimental design was also used to determine the values of the under study variables that provided the greatest biosorption efficiency. A technique for biomass recovery was also developed with the objective of determining the capacity of the regenerated biomass to biosorb the metals in solution. This research proved that with a pH of 4.75, a biomass concentration of 0.7 g/L, and a heavy metal concentration varying between 5 and 10 mg/L a biosorption process of biosorption with Aspergillus niger could be successfully used for heavy metal removal from oil field water in the oil industry.

  12. Biosorption of Cadmium by Fungal Biomass of Aspergillus niger

    Institute of Scientific and Technical Information of China (English)

    QI YANG; JIAN-LONG WANG; ZHI XING

    2005-01-01

    Objective To investigate the removal of cadmium from aqueous solution by waste fungal biomass of Aspergillus niger, originated from citric acid fermentation industry. Methods Batch adsorption test was used to study the biosorption equilibrium and isotherm. The Cd2+ concentration was measured with atomic adsorption spectrophotometer (AAS) HITACHI 180-80. Results The biosorption achieved equilibrium within 30 min. The adsorption isotherm could be described by Freundlich adsorption model, and the constants KF and 1/n were determined to be 2.07 and 0.18, respectively, and the correlation efficiency was 0.97. The optimal pH for Cd adsorption was 6.0. The cadmium-laden biomass could be effectively regenerated using 0.1 N HCl. Conclusion The waste biomass of Aspergillus niger, a by-product of fermentation industry, is a potential biosorbent for the removal of cadmium from aqueous solution.

  13. The Effectiveness of Antifungal Controlling Aspergillus Niger Growth on Plasterboard

    Directory of Open Access Journals (Sweden)

    Parjo Umi Kalthsom

    2017-01-01

    Full Text Available Good indoor environmental quality is desired for a healthy indoor environment. The microbial growth under indoor environments contribute to the poor indoor environmental quality that can cause various of health problems. In this study, the applications of three types of antifungals to prevent microbial migration, subsequent growth and bio-deterioration of the substrates. The aim of this research was to evaluate the coating-bio resistance in remediation of indoor fungal using three types of antifungals with different types of wall finishing materials. The treatment was exposed to optimum temperature and relative humidity at 30°C and 90% respectively. The potassium sorbate, zinc salicylate and calcium benzoate are tested against Aspergillus niger which is collected from indoor rooms. This study has revealed the growth of A. niger are more affected by the potassium sorbate on thick wallpaper, which is the percentage growth are 47%.

  14. Logic in African Philosophy: Examples from two Niger Delta Societies

    Directory of Open Access Journals (Sweden)

    Jones M. Jaja

    2012-04-01

    Full Text Available There have been questions as to whether African Philosophy exists or not. European scholars and some African scholars are at the opposite end of this scholarly debate. The result is the production of various works by Odera Oruka, Omoregbe, Bordunrin, Wright, Maurier and others espousing their views for or against the existence of African Philosophy. This paper attempts to show the existence of a unique Philosophy that deserves to be recognized and rightly known as African Philosophy. It shows the existence of African Logic using examples from two Niger-Delta societies. The paper begins with the concept of Logic in African thought system, the natural nature of it and it’s applicability to these communities especially as it permeates every aspect of the African way of life. The Ibani and Ogoni societies in the Niger-Delta were used as case studies.

  15. FluG affects secretion in colonies of Aspergillus niger.

    Science.gov (United States)

    Wang, Fengfeng; Krijgsheld, Pauline; Hulsman, Marc; de Bekker, Charissa; Müller, Wally H; Reinders, Marcel; de Vries, Ronald P; Wösten, Han A B

    2015-01-01

    Colonies of Aspergillus niger are characterized by zonal heterogeneity in growth, sporulation, gene expression and secretion. For instance, the glucoamylase gene glaA is more highly expressed at the periphery of colonies when compared to the center. As a consequence, its encoded protein GlaA is mainly secreted at the outer part of the colony. Here, multiple copies of amyR were introduced in A. niger. Most transformants over-expressing this regulatory gene of amylolytic genes still displayed heterogeneous glaA expression and GlaA secretion. However, heterogeneity was abolished in transformant UU-A001.13 by expressing glaA and secreting GlaA throughout the mycelium. Sequencing the genome of UU-A001.13 revealed that transformation had been accompanied by deletion of part of the fluG gene and disrupting its 3' end by integration of a transformation vector. Inactivation of fluG in the wild-type background of A. niger also resulted in breakdown of starch under the whole colony. Asexual development of the ∆fluG strain was not affected, unlike what was previously shown in Aspergillus nidulans. Genes encoding proteins with a signal sequence for secretion, including part of the amylolytic genes, were more often downregulated in the central zone of maltose-grown ∆fluG colonies and upregulated in the intermediate part and periphery when compared to the wild-type. Together, these data indicate that FluG of A. niger is a repressor of secretion.

  16. Influence of gibberellins on flower formation in Hyoscyamus niger L.

    OpenAIRE

    2014-01-01

    Gibberellins (GA4+7) and gibberellin-like substances isolated from generatively induced black henbane (Hyoscyamus niger L.) bring about the growth of shoots and a partial differentiation of axillary meristem in black henbane plants grown under non-inductive light conditions. Long-lasting application of gibberellins, however, did not result in full development of flowers in the majority of the plants investigated. Thus, it seems, that gibberellins are not specific flowering hormones in black h...

  17. Preliminary Study on Diverse Carbon Utilization by Transformant Aspergillus niger

    Directory of Open Access Journals (Sweden)

    S. H. Mohammad

    2012-01-01

    Full Text Available Aspergillus niger have been widely recognized as producer of metabolites and reported as good expression hosts for homologous and heterologous proteins. For recombinant expression systems, nature of metabolite production would change when the expression host system is modified via plasmid development. In order to study the diversity of carbon utilization of transformant A.niger and their relation to specific carbon sources that could trigger mannanase production, a new screening system was introduced using Biolog technique to evaluate the growth of the transformant performed on 95 carbon sources. As a result, the transformed A.niger were found able to utilize dextrin and other 27 carbohydrates with majority preferred carbohydrates were identified as monosaccharide, oligosaccharides and some sugar alcohols as the best chosen carbon sources for growth. The relative simplicity and global carbon sources underlying in the biolog system for screening of carbon source make it as a useful tool for the preliminary screening and identification of carbon sources in order to select the best carbon source for medium development.

  18. Bioaccumulation and biosorption of chromium by Aspergillus niger MTCC 2594.

    Science.gov (United States)

    Sandana Mala, John Geraldine; Unni Nair, Balachandran; Puvanakrishnan, Rengarajulu

    2006-06-01

    Chromium toxicity is of prime concern due to chrome tanning processes in the leather sector. Chrome tanning results in the discharge of toxic levels of chromium causing pollution hazards. Chromium levels of Cr(III) and Cr(VI) were high above permissible limits in chrome samples after chrome tanning. The potential of Aspergillus niger MTCC 2594 to accumulate chromium as well as its biosorption capacity is investigated in this study. Bioaccumulation of Cr(III) and Cr(VI) in the spent chrome liquor has resulted in a 75-78% reduction of the initial Cr content in 24-36 h. A. niger biomass is found to be very effective in the biosorption of Cr(III) and Cr(VI) in spent chrome liquor. Maximum adsorption of 83% for biosorption of Cr(III) at 48 h and 79% of Cr(VI) at 36 h in spent chrome liquor is observed. The biosorption characteristics fit well with Langmuir and Freundlich isotherms and the adsorption parameters are evaluated. The biosorption of Cr also follows Lagergren kinetics. A. niger biomass is effectively used for the biosorption of chromium with 79-83% Cr removal in 36-48 h.

  19. Examining Nutritional Adequacy and Dietary Diversity Among Women in Niger.

    Science.gov (United States)

    Cisse-Egbuonye, Nafissatou; Ishdorj, Ariun; McKyer, E L J; Mkuu, Rahma

    2017-01-19

    Objective The purpose of this study was to examine the nutritional adequacy and dietary composition among women residing in Zinder and Maradi of Niger, and the factors that affect the variety of their dietary intake. Methods Data from 3360 women of ages 15-49 were used in the analysis. The variable of interest was the Women Dietary Diversity Score (WDDS), which is the simple sum of scores of the 9 categorized food groups, ranging from 0 to 9. Lower values for WDDS indicate nutritionally inadequate dietary diversity. Analysis included descriptive, Mann-Whitney U test and linear regression. Results The majority of the participants were residing in the Maradi Region (56.7%) and were living in households with both male and female adults (94.9%). The mean WDDS was 3.5 in Zinder compared to 2.5 in Maradi (p food items in both Zinder and Maradi were starchy staple food (98.3%). Region of residence was one of the strong predictor of WDDS. A total number of farmers in the household and Household Dietary Diversity Score (HDDS) had positive and significant effects on WDDS whereas Household Hunger Scale (HHS) had a negative and significant effect on WDDS. Conclusion Niger has one of the highest concentrations of malnutrition in the world. In 2012, approximately 2.5 million Nigeriens were affected by malnutrition. Our study results reinforce the importance to conduct more studies that examine the nutritional intake of women in Niger.

  20. Evolution of uranium distribution and speciation in mill tailings, COMINAK Mine, Niger

    Energy Technology Data Exchange (ETDEWEB)

    Déjeant, Adrien, E-mail: adrien.dejeant@normalesup.org [Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Case 115, 4 place Jussieu, 75005 Paris (France); Université Paris Diderot — Paris VII, 5 rue Thomas Mann, 75013 Paris (France); Galoisy, Laurence [Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Case 115, 4 place Jussieu, 75005 Paris (France); Université Pierre et Marie Curie — Paris VI, 4 place Jussieu, 75005 Paris (France); Roy, Régis [AREVA Mines — Geoscience Department, Tour AREVA, 1 place Jean Millier, 92084 Paris, La Défense (France); Calas, Georges; Boekhout, Flora [Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Case 115, 4 place Jussieu, 75005 Paris (France); Université Pierre et Marie Curie — Paris VI, 4 place Jussieu, 75005 Paris (France); Phrommavanh, Vannapha; Descostes, Michael [AREVA Mines — R& D Department, BAL 0414C-2, Tour AREVA, 1 place Jean Millier, 92084 Paris, La Défense (France)

    2016-03-01

    This study investigated the evolution of uranium distribution and speciation in mill tailings from the COMINAK mine (Niger), in production since 1978. A multi-scale approach was used, which combined high resolution remote sensing imagery, ICP-MS bulk rock analyses, powder X-ray diffraction, Scanning Electron Microscopy, Focused Ion Beam — Transmission Electron Microscopy and X-ray Absorption Near Edge Spectroscopy. Mineralogical analyses showed that some ore minerals, including residual uraninite and coffinite, undergo alteration and dissolution during tailings storage. The migration of uranium and other contaminants depends on (i) the chemical stability of secondary phases and sorbed species (dissolution and desorption processes), and (ii) the mechanical transport of fine particles bearing these elements. Uranium is stabilized after formation of secondary uranyl sulfates and phosphates, and adsorbed complexes on mineral surfaces (e.g. clay minerals). In particular, the stock of insoluble uranyl phosphates increases with time, thus contributing to the long-term stabilization of uranium. At the surface, a sulfate-cemented duricrust is formed after evaporation of pore water. This duricrust limits water infiltration and dust aerial dispersion, though it is enriched in uranium and many other elements, because of pore water rising from underlying levels by capillary action. Satellite images provided a detailed description of the tailings pile over time and allow monitoring of the chronology of successive tailings deposits. Satellite images suggest that uranium anomalies that occur at deep levels in the pile are most likely former surface duricrusts that have been buried under more recent tailings. - Highlights: • The evolution of U distribution and speciation in mill tailings is investigated. • High resolution satellite images provide useful information on tailings evolution. • U and many other elements are enriched in a sulfate-rich duricrust. • Formation of

  1. Novel Route for Agmatine Catabolism in Aspergillus niger Involves 4-Guanidinobutyrase.

    Science.gov (United States)

    Kumar, Sunil; Saragadam, Tejaswani; Punekar, Narayan S

    2015-08-15

    Agmatine, a significant polyamine in bacteria and plants, mostly arises from the decarboxylation of arginine. The functional importance of agmatine in fungi is poorly understood. The metabolism of agmatine and related guanidinium group-containing compounds in Aspergillus niger was explored through growth, metabolite, and enzyme studies. The fungus was able to metabolize and grow on l-arginine, agmatine, or 4-guanidinobutyrate as the sole nitrogen source. Whereas arginase defined the only route for arginine catabolism, biochemical and bioinformatics approaches suggested the absence of arginine decarboxylase in A. niger. Efficient utilization by the parent strain and also by its arginase knockout implied an arginase-independent catabolic route for agmatine. Urea and 4-guanidinobutyrate were detected in the spent medium during growth on agmatine. The agmatine-grown A. niger mycelia contained significant levels of amine oxidase, 4-guanidinobutyraldehyde dehydrogenase, 4-guanidinobutyrase (GBase), and succinic semialdehyde dehydrogenase, but no agmatinase activity was detected. Taken together, the results support a novel route for agmatine utilization in A. niger. The catabolism of agmatine by way of 4-guanidinobutyrate to 4-aminobutyrate into the Krebs cycle is the first report of such a pathway in any organism. A. niger GBase peptide fragments were identified by tandem mass spectrometry analysis. The corresponding open reading frame from the A. niger NCIM 565 genome was located and cloned. Subsequent expression of GBase in both Escherichia coli and A. niger along with its disruption in A. niger functionally defined the GBase locus (gbu) in the A. niger genome.

  2. Y-chromosomal variation in sub-Saharan Africa: insights into the history of Niger-Congo groups.

    Science.gov (United States)

    de Filippo, Cesare; Barbieri, Chiara; Whitten, Mark; Mpoloka, Sununguko Wata; Gunnarsdóttir, Ellen Drofn; Bostoen, Koen; Nyambe, Terry; Beyer, Klaus; Schreiber, Henning; de Knijff, Peter; Luiselli, Donata; Stoneking, Mark; Pakendorf, Brigitte

    2011-03-01

    Technological and cultural innovations as well as climate changes are thought to have influenced the diffusion of major language phyla in sub-Saharan Africa. The most widespread and the richest in diversity is the Niger-Congo phylum, thought to have originated in West Africa ∼ 10,000 years ago (ya). The expansion of Bantu languages (a family within the Niger-Congo phylum) ∼ 5,000 ya represents a major event in the past demography of the continent. Many previous studies on Y chromosomal variation in Africa associated the Bantu expansion with haplogroup E1b1a (and sometimes its sublineage E1b1a7). However, the distribution of these two lineages extends far beyond the area occupied nowadays by Bantu-speaking people, raising questions on the actual genetic structure behind this expansion. To address these issues, we directly genotyped 31 biallelic markers and 12 microsatellites on the Y chromosome in 1,195 individuals of African ancestry focusing on areas that were previously poorly characterized (Botswana, Burkina Faso, Democratic Republic of Congo, and Zambia). With the inclusion of published data, we analyzed 2,736 individuals from 26 groups representing all linguistic phyla and covering a large portion of sub-Saharan Africa. Within the Niger-Congo phylum, we ascertain for the first time differences in haplogroup composition between Bantu and non-Bantu groups via two markers (U174 and U175) on the background of haplogroup E1b1a (and E1b1a7), which were directly genotyped in our samples and for which genotypes were inferred from published data using linear discriminant analysis on short tandem repeat (STR) haplotypes. No reduction in STR diversity levels was found across the Bantu groups, suggesting the absence of serial founder effects. In addition, the homogeneity of haplogroup composition and pattern of haplotype sharing between Western and Eastern Bantu groups suggests that their expansion throughout sub-Saharan Africa reflects a rapid spread followed by

  3. Assessment of environmental change and its socio-economic impacts in the mangrove ecological zone of the Niger Delta, Nigeria

    Science.gov (United States)

    James, Godstime Kadiri

    The Niger Delta, located in the central part of Southern Nigeria, is endowed with immense Mangrove resources, estimated to be the fourth largest in the world. The term Mangrove refers to salt tolerant species of trees or shrubs that grow on shores and in estuaries located in the coastal tropics and sub-tropical regions of the world. They support highly productive marine food chains. However, Mangrove ecosystems are in serious decline around the world due to the rapid increase in maritime commerce and exploration of mineral resources in the last few decades. These pressures often have immediate consequences on sensitive coastal environments and can potentially impact future human use of coastal space and resources. This dynamic process presents unique opportunities for research to explore the nature and consequences of these pressures. This dissertation focused on the Mangrove ecological zone of the Niger Delta, where resource exploitation and indigenous use of the environment are in direct conflict with important socio-economic implications. Environmental accounting metrics derived from the Driver-Pressure-State-Impact-Response (DPSIR) framework were used to assess changes in the spatial extent of the Niger Delta Mangrove ecosystem and the socio-economic impacts of the observed changes. Landsat remotely sensed satellite data from the mid-1980s through 2003 was used to assess change in the spatial extent of the Mangrove vegetation in the region. A total of 21,340 hectares of Mangrove forest was determined to be lost over the study period. Field research in the region confirmed that this loss was primarily driven by urbanization and activities of the multinational oil and gas corporations operating in the region. To estimate the socio-economic impacts of the Mangrove loss in the region, neoclassical economic valuation and participatory social valuation approaches were adopted. Results from the economic valuation revealed that the net present value of future income

  4. Aggregate and Mineral Resources - Minerals

    Data.gov (United States)

    NSGIC State | GIS Inventory — This point occurrence data set represents the current mineral and selected energy resources of Utah. The data set coordinates were derived from USGS topographic maps...

  5. About eco-ethical problems of Azerbaijan Republic

    Directory of Open Access Journals (Sweden)

    G. Sh. Mammadov

    2017-03-01

    Full Text Available Starting from the second half of the 20th century Ecological problems, that engulfed the world had an influence on our republic as well. Pollution of air and water basins and soils has reached for apogee, the process of degradation of winter and summer pastures has decreased, in some regions forests have been completely or partly destroyed. Consequences of fluctuation of sea level, problems related to ozone layer, global changes of climate being combined with other wide-scale processes have reached the extent at which they can not be neglected in Azerbaijan Republic. Where as global thinking and civilized relations between nations are being formed, international prestige of the state is starting to be estimated by its attitude to the nature and natural resources. Therefore at present time Azerbaijan Republic society pays incremental attention to its attitude towards environment, natural ecosystems, surface and underground minerals. In the article the approach aimed to solution of eco-ethical problems in Azerbaijan Republic has been used.

  6. Fumarolic minerals

    DEFF Research Database (Denmark)

    Balic Zunic, Tonci; Garavelli, Anna; Jakobsson, Sveinn Peter

    2016-01-01

    The fumarolic mineralogy of the Icelandic active volcanoes, the Tyrrhenian volcanic belt (Italy) and the Aegean active arc (Greece) is investigated, and literature data surveyed in order to define the characteristics of the European fumarolic systems. They show broad diversity of mineral...... associations, with Vesuvius and Vulcano being also among the world localities richest in mineral species. Volcanic systems, which show recession over a longer period, show fumarolic development from the hightemperature alkaline halide/sulphate, calcic sulphate or sulphidic parageneses, synchronous...... fluctuations in activity, illustrated by the example of Vulcano where the high-temperature association appears intermittently. A full survey of the mineral groups and species is given in respect to their importance and appearance in fumarolic associations....

  7. Reduced by-product formation and modified oxygen availability improve itaconic acid production in Aspergillus niger.

    NARCIS (Netherlands)

    Li, A.; Pfelzer, N.; Zuijderwijk, R.; Brickwedde, A.; Zeijl, C. van; Punt, P.

    2013-01-01

    Aspergillus niger has an extraordinary potential to produce organic acids as proven by its application in industrial citric acid production. Previously, it was shown that expression of the cis-aconitate decarboxylase gene (cadA) from Aspergillus terreus converted A. niger into an itaconic acid produ

  8. Can hTNF-alpha be successfully produced and secreted in filamentous fungus Aspergillus niger?

    NARCIS (Netherlands)

    Krasevec, N.; Hondel, C.A.M.J.J. van den; Komel, R.

    2000-01-01

    A gene-fusion expression strategy was applied for the heterologous expression of hTNF-α in A. niger AB1.13. The TNF-α gene was fused with the A. niger glucoamylase GII form as a carrier-gene, behind its transcription control and secretion signal. The protein was expressed in the cells in the form of

  9. Genome sequencing and analysis of the versatile cell factory Aspergillus niger CBS 513.88

    DEFF Research Database (Denmark)

    Pel, Herman J.; de Winde, Johannes H.; Archer, David B.

    2007-01-01

    The filamentous fungus Aspergillus niger is widely exploited by the fermentation industry for the production of enzymes and organic acids, particularly citric acid. We sequenced the 33.9-megabase genome of A. niger CBS 513.88, the ancestor of currently used enzyme production strains. A high level...

  10. Corporate Social Responsibility: Case Study of Community Expectations and the Administrative Systems, Niger Delta

    Science.gov (United States)

    Ogula, David

    2012-01-01

    Poor community-company relations in the Niger Delta have drawn attention to the practice of corporate social responsibility (CSR) in the region. Since the 1960s, transnational oil corporations operating in the Niger Delta have adopted various CSR strategies, yet community-company relations remain adversarial. This article examines community…

  11. Assessment of the pectinolytic network of Aspergillus niger by functional genomics : insights from the transcriptome

    NARCIS (Netherlands)

    Martens-Uzunova, E.S.

    2008-01-01

    More than a century ago, in 1889, A. Fernbach presented a detailed report about the invertase of Aspergillus niger in the third edition of “Annales De L'institut Pasteur”. Since then, many of the enzymes secreted by A. niger have found a broad range of applications, and today they are produced on an

  12. Aspergillus niger RhaR, a regulator involved in L-rhamnose release and catabolism

    NARCIS (Netherlands)

    Gruben, B.S.; Zhou, M.; Wiebenga, A.; Ballering, J.; Overkamp, K.M.; Punt, P.J.; Vries, R.P. de

    2014-01-01

    The genome of the filamentous fungus Aspergillus niger is rich in genes encoding pectinases, a broad class of enzymes that have been extensively studied due to their use in industrial applications. The sequencing of the A. niger genome provided more knowledge concerning the individual pectinolytic g

  13. Flood forests of the inner Niger delta, mali; past, present, and future

    NARCIS (Netherlands)

    Beintema, A.J.; Fofana, B.; Faye, A.; Huiskes, H.P.J.

    2005-01-01

    Flood forests have a special place in the Inner Niger Delta, Mali. They have a great economic value for the local populations, and are hotspots of biodiversity in the delta. This report reviews the status of all flood forests in the Inner Niger Delta, Mali, that are presently known, or have been kno

  14. Trends in HIV seropositivity among young adults in the Niger Delta ...

    African Journals Online (AJOL)

    Trends in HIV seropositivity among young adults in the Niger Delta of ... a cosmopolitan city in the Niger Delta, the heart of the oil and gas industry in Nigeria. ... and social changes coupled with the provision of youth friendly health services.

  15. Characterization of oxylipins and dioxygenase genes in the asexual fungus Aspergillus niger

    NARCIS (Netherlands)

    Wadman, Mayken W; de Vries, Ronald P; Kalkhove, Stefanie I C; Veldink, Gerrit A; Vliegenthart, Johannes F G

    2009-01-01

    BACKGROUND: Aspergillus niger is an ascomycetous fungus that is known to reproduce through asexual spores, only. Interestingly, recent genome analysis of A. niger has revealed the presence of a full complement of functional genes related to sexual reproduction 1. An example of such genes are the dio

  16. The molecular and genetic basis of conidial pigmentation in Aspergillus niger

    DEFF Research Database (Denmark)

    Jørgensen, Thomas R.; Park, Joohae; Arentshorst, Mark

    2011-01-01

    A characteristic hallmark of Aspergillus niger is the formation of black conidiospores. We have identified four loci involved in spore pigmentation of A. niger by using a combined genomic and classical complementation approach. First, we characterized a newly isolated color mutant, colA, which la...

  17. Database mining and transcriptional analysis of genes encoding inulin-modifying enzymes of Aspergillus niger

    NARCIS (Netherlands)

    Yuan, X.L.; Goosen, C.; Kools, H.J.; Maarel, van der M.J.; Hondel, van den C.A.M.J.J.; Dijkhuizen, L.; Ram, A.F.

    2006-01-01

    As a soil fungus, Aspergillus niger can metabolize a wide variety of carbon sources, employing sets of enzymes able to degrade plant-derived polysaccharides. In this study the genome sequence of A. niger strain CBS 513.88 was surveyed, to analyse the gene/enzyme network involved in utilization of th

  18. Identification and characterization of starch and inulin modifying network of Aspergillus niger by functional genomics

    NARCIS (Netherlands)

    Yuan, Xiao-Lian

    2008-01-01

    Aspergillus niger produces a wide variety of carbohydrate hydrolytic enzymes which have potential applications in the baking, starch, textile, food and feed industries. The goal of this thesis is to unravel the molecular mechanisms of starch and inulin modifying network of A. niger, in order to impr

  19. Production of Extracellular Lipase from Aspergillus niger by Solid-State Fermentation

    Directory of Open Access Journals (Sweden)

    Janny Coca Armas

    2006-01-01

    Full Text Available Lipase production in Aspergillus niger J-1 was tested using both submerged fermentation (SmF and solid-state fermentation (SSF on a mineral culture medium and wheat bran, respectively. The optimization of the culture medium was carried out for both SmF and SSF. The maximum lipase activity, 1.46 IU/mL, was obtained during the submerged fermentation in a medium containing glucose at 2 % and olive oil at 2 % under conditions of 1 vvm and 450 m–1. However, 9.14 IU/g of dry solid substrate equivalent to 4.8 IU/mL of lipase activity was reached using solid-state fermentation process with a medium containing 0.75 % of ammonium sulphate and 0.34 % of urea. The optimum pH and temperature for enzymatic activity were pH=6 and 40 °C, respectively. The enzyme also exhibited 80 % of its initial activity in neutral and mildly acid media and at temperatures between 20 and 30 °C for a period of 24 hours.

  20. Citric acid production from Aspergillus niger MT-4 using hydrolysate extract of the insect Locusta migratoria.

    Science.gov (United States)

    Taskin, Mesut; Tasar, Gani Erhan; Incekara, Umit

    2013-06-01

    Citric acid (CA) is the most important organic acid used in the food and other industries. Locusta migratoria is an insect species, which has rich nutritional composition (especially protein) and cultivated in some countries. Therefore, the present study investigated the usability of hydrolysate extract of L. migratoria biomass as substrate for the production of CA from Aspergillus niger MT-4. The insect extract (IE) was found to be rich in ash (34.9 g/100 g), protein (35.6 g/100 g) and mineral contents. Yeast extract was found to be the most favorable substrate for biomass production, whereas the maximum production of CA (41.8 g/L) was achieved in the medium containing IE. Besides, uniform pellets with the smallest size (4 mm) were observed in IE medium. It was thought that rich magnesium (6.78 g/100 g) and manganese (1.14 g/100 g) contents of IE increased the production of CA, resulting in the formation of small uniform pellets. This is the first report on the effect of protein-rich insect biomasses on the production of CA. In this regard, L. migratoria biomass was tested for the first time as a CA-production substrate.

  1. A refined estimate of the malaria burden in Niger

    Directory of Open Access Journals (Sweden)

    Doudou Maimouna

    2012-03-01

    Full Text Available Abstract Background The health authorities of Niger have implemented several malaria prevention and control programmes in recent years. These interventions broadly follow WHO guidelines and international recommendations and are based on interventions that have proved successful in other parts of Africa. Most performance indicators are satisfactory but, paradoxically, despite the mobilization of considerable human and financial resources, the malaria-fighting programme in Niger seems to have stalled, as it has not yet yielded the expected significant decrease in malaria burden. Indeed, the number of malaria cases reported by the National Health Information System has actually increased by a factor of five over the last decade, from about 600,000 in 2000 to about 3,000,000 in 2010. One of the weaknesses of the national reporting system is that the recording of malaria cases is still based on a presumptive diagnosis approach, which overestimates malaria incidence. Methods An extensive nationwide survey was carried out to determine by microscopy and RDT testing, the proportion of febrile patients consulting at health facilities for suspected malaria actually suffering from the disease, as a means of assessing the magnitude of this problem and obtaining a better estimate of malaria morbidity in Niger. Results In total, 12,576 febrile patients were included in this study; 57% of the slides analysed were positive for the malaria parasite during the rainy season, when transmission rates are high, and 9% of the slides analysed were positive during the dry season, when transmission rates are lower. The replacement of microscopy methods by rapid diagnostic tests resulted in an even lower rate of confirmation, with only 42% of cases testing positive during the rainy season, and 4% during the dry season. Fever alone has a low predictive value, with a low specificity and sensitivity. These data highlight the absolute necessity of confirming all reported

  2. Pharmacognostical and phytochemical studies of Helleborus niger L root

    Directory of Open Access Journals (Sweden)

    V Kishor Kumar

    2017-01-01

    Full Text Available Background: Helleborus niger L (Ranunculaceae is used Ayurvedic and Unani systems and other herbal medicine systems. The roots of H. niger have a good medicinal value. Aims: To conduct a pharmacognostical and phytochemical study of H. niger. Materials and Methods: The pharmacognostical studies on roots including parameters such as taxonomical, macroscopic, microscopic characters, physico-chemical, ultra-violet analysis and phytochemical studies are established. Results: Macroscopically, the roots are brownish-black in colour, cylindrical in shape, feeble odour, slightly acrid taste with irregularly branched. Microscopically the root showed the presence of epidermis, air-chambers, fissure periderm, periderm, inner cortex, pith, phloem, xylem, vessels and xylem vessels. Microscopic examination of the powder showed the presence of parenchyma cells, parenchyma mass, periderm, cell inclusion, laticifer, lateral wall pith, perforation, xylem bundle and xylem elements. Ultra-violet and ordinary light analyses with different reagents were conducted to identify the drug in powder form. Physico-chemical evaluation established, Ash values - Total, acid insoluble, water soluble and sulphated ash values were 7.3%, 4.1%, 3.7% and 5.2%, respectively. Extractive values - Alcohol soluble, water soluble and ether soluble extractive values were 22.8%, 7.4% and 5.6%, respectively. Loss on drying was 3.3%. Preliminary phytochemical screening showed the presence of carbohydrate, glycoside, saponins, flavonoid, phytosterols, tannins and phenolic compounds. Conclusions: The results of the study can serve as a valuable resource of pharmacognostic and phytochemical information. This will serve as appropriate, standards for discovery of this plant material in future investigations and applications and also contribute towards establishing pharmacopoeial standards.

  3. Pharmacognostical and Phytochemical Studies of Helleborus niger L Root.

    Science.gov (United States)

    Kumar, V Kishor; Lalitha, K G

    2017-01-01

    Helleborus niger L (Ranunculaceae) is used Ayurvedic and Unani systems and other herbal medicine systems. The roots of H. niger have a good medicinal value. To conduct a pharmacognostical and phytochemical study of H. niger. The pharmacognostical studies on roots including parameters such as taxonomical, macroscopic, microscopic characters, physico-chemical, ultra-violet analysis and phytochemical studies are established. Macroscopically, the roots are brownish-black in colour, cylindrical in shape, feeble odour, slightly acrid taste with irregularly branched. Microscopically the root showed the presence of epidermis, air-chambers, fissure periderm, periderm, inner cortex, pith, phloem, xylem, vessels and xylem vessels. Microscopic examination of the powder showed the presence of parenchyma cells, parenchyma mass, periderm, cell inclusion, laticifer, lateral wall pith, perforation, xylem bundle and xylem elements. Ultra-violet and ordinary light analyses with different reagents were conducted to identify the drug in powder form. Physico-chemical evaluation established, Ash values - Total, acid insoluble, water soluble and sulphated ash values were 7.3%, 4.1%, 3.7% and 5.2%, respectively. Extractive values - Alcohol soluble, water soluble and ether soluble extractive values were 22.8%, 7.4% and 5.6%, respectively. Loss on drying was 3.3%. Preliminary phytochemical screening showed the presence of carbohydrate, glycoside, saponins, flavonoid, phytosterols, tannins and phenolic compounds. The results of the study can serve as a valuable resource of pharmacognostic and phytochemical information. This will serve as appropriate, standards for discovery of this plant material in future investigations and applications and also contribute towards establishing pharmacopoeial standards.

  4. The Republic of Yemen Petroleum Overview

    Institute of Scientific and Technical Information of China (English)

    NEDHAM Mohammed Darsi

    2001-01-01

    AbstractYemen located on the southwest corner of the Arabian Peninsula. It is known that Yemen is important to world energy markets because of its oil and natural gas resources as well as its strategic location at the Bab el - Mandab strait linking the Red Sea and the Gulf of Aden. Due to the Ministry of Oil and Mineral Resources (MOMR, 1998E) the Yemeni Oil Production was estimated to be 385 000 barrels per day (bbl/d), Oil Consumption was 69 000 bbl/d and Net Oil Exports was 316 000 barrels per day (bbl/d). On 1999 the Yemeni Proven Oil Reserves was estimated to be 4 billion barrels and the Natural Gas Reserves was estimated to be 16.9 trillion cubic feet (Tcf) (Ministry of Oil and Mineral Resources, 1999). At this time, many researchers, scientific expeditions and foreign companies are interested in Yemen. This paper discussed the petroleum overview of the Republic of Yemen. In my opinion, Yemen is not just going to attract all with its oil and gas discoveries in the near future, but also with its new geological data and information.

  5. Expression of Aspergillus niger 9891 Endoinulinase in Pichia pastoris

    Institute of Scientific and Technical Information of China (English)

    Wang Jianhua(王建华); Teng Da; Yao Yi; Yang Yalin; Zhang Fan

    2004-01-01

    An endoinulinase gene from Aspergillus niger 9891 (CGMCC0991) has been expressed in Pichia pastoris GS115 using pPIC9 vector. The recombinant endoinulinase was highly expressed and the optimization of the expression in a 7 liter of fermentor has been investigated. In fermented broth, the concentration of protein secreted is 2.15 mg/ml. The activity of endoinulinase is 1501 U/ml with sucrose as substrate and 291 U/ml with inulin as substrate, 105 and 273 times higher than that from the original strain respectively.

  6. Recombinant bacterial hemoglobin alters metabolism of Aspergillus niger

    DEFF Research Database (Denmark)

    Hofmann, Gerald; Diano, Audrey; Nielsen, Jens

    2009-01-01

    The filamentous fungus Aspergillus niger is used extensively for the production of enzymes and organic acids. A major problem in industrial fermentations with this fungus is to ensure sufficient supply of oxygen required for respiratory metabolism of the fungus. In case of oxygen limitation...... behind the strong gpdA promoter from Aspergillus nidulans. Analysis of secreted metabolites, oxygen uptake, CO2 evolution and biomass formation points towards a relief of stress in the mutant expressing VHB when it is exposed to oxygen limitation. Our findings therefore point to an interesting strategy...

  7. Production of Citric Acid by Aspergillus niger Using Pineapple Waste

    OpenAIRE

    S. O. Kareem; Akpan, I.; Alebiowu, O. O.

    2010-01-01

    A solid state fermentation was developed for citric acid production from pineapple waste by Aspergillus niger KS-7. The medium was supplemented with different concentration of glucose, sucrose, ammonium nitrate and ammonium phosphate. It was found that pineapple waste with 15% (w/v) sucrose and ammonium nitrate (0.25% w/v) gave the optimum citric acid secretion (60.61 g/kg) in the presence of methanol (2% v/v) when fermented for 5 days at 30 °C with the initial moisture content of 65%. The ...

  8. Chitosan Obtained from Cell Wall of Aspergillus Niger Mycelium

    Institute of Scientific and Technical Information of China (English)

    HUANG Hui-li; LIN Wen-luan; LIN Jian-ming

    2004-01-01

    Chitin from cell walls of Aspergillus Niger mycelium was prepared. A new method for the preparation of high deacetylation degree chitosan was studied in a dilute sodium hydroxide solution at a high pressure. The experimental results indicate that the deacetylation degree of the chitosan can reach 80% under the condition of a 5.00 mol/L sodium hydroxide solution at 0.1 MPa of pressure for 1 h. This method shows the advantages of the applications in the industry production and environment protection.

  9. Oil Bunkering Activities in the Niger Delta "The Way Forward"

    OpenAIRE

    2016-01-01

    Bunkeringis the practice and business whereby duly licensed operators stores petroleum products in tanks and subsequently provide fuels, water and lubricants (bunkering services) for marine services on request. It could be likened to establishing a floating fuel service station on the high seas or at coastal jetties to supply fuel and provisions of water to ships. The Niger Delta is a host to Nigeria’s proved Oil and Gas reserves. In this study, the history of Bunker oïl and the v...

  10. Study on secondary metabolite content of Helleborus niger L. leaves.

    Science.gov (United States)

    Vitalini, Sara; Braca, Alessandra; Fico, Gelsomina

    2011-03-01

    Phytochemical investigation of Helleborus niger L. (Ranunculaceae) leaf methanol extract allowed to isolate a phenolic glucoside derivative and two flavonoid glycosides characterized as phenyllactic acid 2-O-β-D-glucopyranoside (1), quercetin 3-O-2-(E-caffeoyl)-α-L-arabinopyranosyl-(1 → 2)-β-D-glucopyranoside-7-O-β-D-glucopyranoside (2), and kaempferol 3-O-α-L-arabinopyranosyl-(1 → 2)-β-D-galactopyranoside-7-O-β-D-glucopyranoside (3), respectively. Compounds 1 and 2 were isolated for the first time and their structural characterization was obtained on the basis of extensive NMR spectral studies. Copyright © 2010 Elsevier B.V. All rights reserved.

  11. Mantle electrical conductivity profile of Niger delta region

    Indian Academy of Sciences (India)

    Daniel N Obiora; Francisca N Okeke; K Yumoto; Stan O Agha

    2014-06-01

    The mantle electrical conductivity-depth profile of the Niger delta region in Nigeria has been determined using solar quiet day ionospheric current (Sq).The magnetometer data obtained in 2010 from geomagnetic stations installed in Lagos by magnetic dataset (MAGDAS) in 2008 and data from magnetometers installed in some parts of Niger delta by Center for Basic Space Science, University of Nigeria, Nsukka, were employed in this study. Gauss spherical harmonic analysis (SHA) method was used to separate the internal and external field contributions to Sq current system. The result depicted that the conductivity profile rose steadily from about 0.032 S/m at a depth of 89 km to 0.041 S/m at 100 km and 0.09 S/m at 221 km. This high conductivity region agreed with the global seismic low velocity region, the asthenosphere. The conductivity profile continued increasing downward until it got to 0.157 S/m at a depth of about 373 km (close to the base of upper mantle), 0.201 S/m at 784 km and reached 0.243 S/m at a depth of 1179 km at the lower mantle.

  12. Factors Affecting Rural Households’ Resilience to Food Insecurity in Niger

    Directory of Open Access Journals (Sweden)

    Aboubakr Gambo Boukary

    2016-03-01

    Full Text Available Niger faces many natural and human constraints explaining the erratic evolution of its agricultural production over time. Unfortunately, this is likely to cause a decline in the food supply. This study attempts to identify factors affecting rural households’ resilience to food insecurity in Niger. For this, we first create a resilience index by using principal component analysis and later apply structural equation modeling to identify its determinants. Data from the 2010 National Survey on Households’ Vulnerability to Food Insecurity done by the National Institute of Statistics is used. The study shows that asset and social safety net indicators are significant and have a positive impact on households’ resilience. Climate change approximated by long-term mean rainfall has a negative and significant effect on households’ resilience. Therefore, to strengthen households’ resilience to food insecurity, there is a need to increase assistance to households through social safety nets and to help them gather more resources in order to acquire more assets. Furthermore, early warning of climatic events could alert households, especially farmers, to be prepared and avoid important losses that they experience anytime an uneven climatic event occurs.

  13. Remote Sensing of Water Quality in the Niger River Basin

    Science.gov (United States)

    Mueller, C.; Palacios, S. L.; Milesi, C.; Schmidt, C.; Baney, O. N.; Mitchell, Å. R.; Kislik, E.; Palmer-Moloney, L. J.

    2015-12-01

    An overarching goal of the National Geospatial Intelligence Agency (NGA) Anticipatory Analytics- -GEOnarrative program is to establish water linkages with energy, food, and climate and to understand how these linkages relate to national security and stability. Recognizing that geopolitical stability is tied to human health, agricultural productivity, and natural ecosystems' vitality, NGA partnered with NASA Ames Research Center to use satellite remote sensing to assess water quality in West Africa, specifically the Niger River Basin. Researchers from NASA Ames used MODIS and Landsat imagery to apply two water quality indices-- the Floating Algal Index (FAI) and the Turbidity Index (TI)--to large rivers, lakes and reservoirs within the Niger Basin. These indices were selected to evaluate which observations were most suitable for monitoring water quality in a region where coincident in situ measurements are not available. In addition, the FAI and TI indices were derived using data from the Hyperspectral Imagery for the Coastal Ocean (HICO) sensor for Lake Erie in the United States to determine how increased spectral resolution and in-situ measurements would improve the ability to measure the spatio-temporal variations in water quality. Results included the comparison of outputs from sensors with different spectral and spatial resolution characteristics for water quality monitoring. Approaches, such as the GEOnarrative, that incorporate water quality will enable analysts and decision-makers to recognize the current and potentially future impacts of changing water quality on regional security and stability.

  14. Initial intracellular proteome profile of Aspergillus niger biofilms

    Directory of Open Access Journals (Sweden)

    Gretty K. Villena

    2011-07-01

    Full Text Available An initial profiling of the intracellular proteome of Aspergillus niger ATCC 10864 biofilm cultures developed on polyester cloth was carried out by using 2D-PAGE and MS-TOF analysis and it was compared to the proteome of conventionally grown free-living submerged cultures. A number of 2D-PAGE protein spots from both types of cultures were subjected to MS-TOF analysis and data interrogation of the NCBI nr database available for this species. Proteomic maps showed different expression patterns in both culture systems with differentially expressed proteins in each case. In biofilm cultures, 19% and 32% of the selected protein spots were over- expressed and differentially expressed, respectively. On the contrary, in free-living cultures, 44% and 7% of the selected protein spots were over-expressed and differentially expressed, respectively. Although preliminary, results presented in this paper show that there are significant differences between the proteomes of A. niger biofilm and free-living mycelia. It seems that cell adhesion is the most important stimulus responsible for biofilm development which is the basis of Surface Adhesion Fermentation.

  15. Maturation of conidia on conidiophores of Aspergillus niger.

    Science.gov (United States)

    Teertstra, Wieke R; Tegelaar, Martin; Dijksterhuis, Jan; Golovina, Elena A; Ohm, Robin A; Wösten, Han A B

    2017-01-01

    Conidia of Aspergillus niger are produced on conidiophores. Here, maturation of conidia on these asexual reproductive structures was studied. Pigmented conidia that had developed on conidiophores for 2, 5, and 8days were similarly resistant to heat and were metabolically active as shown by CO2 release and conversion of the metabolic probe Tempone. A total number of 645-2421 genes showed a ⩾2-fold change in expression when 2-day-old conidia were compared to 5- and 8-day-old spores. Melanin was extracted more easily from the cell wall of 2-day-old conidia when compared to the older spores. In addition, mannitol content and germination rate of the 2-day-old conidia were higher. Dispersal efficiency by water was lower in the case of the 8-day-old conidia but no differences were observed in dispersal by wind and a hydrophobic moving object. These data and the fact that only a minor fraction of the conidia on a conidiophore were dispersed in the assays imply that a single colony of A. niger releases a heterogeneous population of conidia. This heterogeneity would provide a selective advantage in environments with rapidly changing conditions such as availability of water. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  16. Oil Bunkering Activities in the Niger Delta "The Way Forward"

    Directory of Open Access Journals (Sweden)

    Orijialurechi Boniface

    2016-04-01

    Full Text Available Bunkeringis the practice and business whereby duly licensed operators stores petroleum products in tanks and subsequently provide fuels, water and lubricants (bunkering services for marine services on request. It could be likened to establishing a floating fuel service station on the high seas or at coastal jetties to supply fuel and provisions of water to ships. The Niger Delta is a host to Nigeria’s proved Oil and Gas reserves. In this study, the history of Bunker oïl and the various types of bunkers were examined; Bunker trade, transportation of bunker fuel and the various types of vessels used were also analyzed. The study provides accurate information on how the bunkering business could be managed using world best practices for the economic benefit of the Nigerian economy thereby creating jobs for citizens and income for the gouvernement. Also, this research gives a guide line on how to re-orient Nigerian citizens on the legitimacy and the economic potential for the bunkering business in Niger Delta. The results showed that an organized bunker trade would add positively to the GDP of Nigeria

  17. Starch-binding domain shuffling in Aspergillus niger glucoamylase.

    Science.gov (United States)

    Cornett, Catherine A G; Fang, Tsuei-Yun; Reilly, Peter J; Ford, Clark

    2003-07-01

    Aspergillus niger glucoamylase (GA) consists mainly of two forms, GAI [from the N-terminus, catalytic domain + linker + starch-binding domain (SBD)] and GAII (catalytic domain + linker). These domains were shuffled to make RGAI (SBD + linker + catalytic domain), RGAIDeltaL (SBD + catalytic domain) and RGAII (linker + catalytic domain), with domains defined by function rather than by tertiary structure. In addition, Paenibacillus macerans cyclomaltodextrin glucanotransferase SBD replaced the closely related A.niger GA SBD to give GAE. Soluble starch hydrolysis rates decreased as RGAII approximately GAII approximately GAI > RGAIDeltaL approximately RGAI approximately GAE. Insoluble starch hydrolysis rates were GAI > RGAIDeltaL > RGAI > GAE approximately RGAII > GAII, while insoluble starch-binding capacities were GAI > RGAI > RGAIDeltaL > RGAII > GAII > GAE. These results indicate that: (i) moving the SBD to the N-terminus or replacing the native SBD somewhat affects soluble starch hydrolysis; (ii) SBD location significantly affects insoluble starch binding and hydrolysis; (iii) insoluble starch hydrolysis is imperfectly correlated with its binding by the SBD; and (iv) placing the P.macerans cyclomaltodextrin glucanotransferase SBD at the end of a linker, instead of closely associated with the rest of the enzyme, severely reduces its ability to bind and hydrolyze insoluble starch.

  18. Triangulation, Emotional Reactivity, and Violence in the Niger Delta

    Directory of Open Access Journals (Sweden)

    Benjamin Aigbe Okonofua

    2013-04-01

    Full Text Available The Niger Delta conflict, for many years, was blamed on myriad forces, including greed, economic exploitation, pollution and ecological damage, resource appropriation and distribution disputes, ethno-religious antagonisms, poverty, unemployment, large-scale infrastructural deficits, corruption, militarization of oil producing communities and election processes, sociopolitical marginalization, cultism, and weapons proliferation. While all of these issues are important, they are not nearly as important as the deliberate roles played by high-level social, economic, and political interests who activated violence as a means to secure economic advantage from the delta’s oil industry. This study shines the light on this small, exclusive, and very powerful group whose actions triggered off the violence and yet are at the center of efforts to institute peace including the current disarmament, demobilization, and reintegration (DDR program. I argue that unless the contributions of these powerful interests are carefully teased out and the structures they have built to advantage themselves from the conflict are dismantled, peace will remain elusive in the Niger Delta.

  19. Removing the regional level from the Niger vaccine supply chain.

    Science.gov (United States)

    Assi, Tina-Marie; Brown, Shawn T; Kone, Souleymane; Norman, Bryan A; Djibo, Ali; Connor, Diana L; Wateska, Angela R; Rajgopal, Jayant; Slayton, Rachel B; Lee, Bruce Y

    2013-06-10

    Since many of the world's vaccine supply chains contain multiple levels, the question remains of whether removing a level could bring efficiencies. We utilized HERMES to generate a detailed discrete-event simulation model of Niger's vaccine supply chain and compared the current four-tier (central, regional, district, and integrated health center levels) with a modified three-tier structure (removing the regional level). Different scenarios explored various accompanying shipping policies and frequencies. Removing the regional level and implementing a collection-based shipping policy from the district stores increases vaccine availability from a mean of 70-100% when districts could collect vaccines at least weekly. Alternatively, implementing a delivery-based shipping policy from the central store monthly in three-route and eight-route scenarios only increases vaccine availability to 87%. Restricting central-to district vaccine shipments to a quarterly schedule for three-route and eight-route scenarios reduces vaccine availability to 49%. The collection-based shipping policy from district stores reduces supply chain logistics cost per dose administered from US$0.14 at baseline to US$0.13 after removing the regional level. Removing the regional level from Niger's vaccine supply chain can substantially improve vaccine availability as long as certain concomitant adjustments to shipping policies and frequencies are implemented. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Mineral bioprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Torma, A.E.

    1993-05-01

    In the last 25 years, the introduction of biotechnological methods in hydrometallurgy has created new opportunities and challenges for the mineral processing industry. This was especially true for the production of metal values from mining wastes and low-and-complex-grade mineral resources, which were considered economically not amenable for processing by conventional extraction methods. Using bio-assisted heap, dump and in-situ leaching technologies, copper and uranium extractions gained their first industrial applications. The precious metal industries were the next to adopt the bio-preoxidation technique in the extraction of gold from refractory sulfide-bearing ores and concentrates. A variety of other bioleaching opportunities exist for nickel, cobalt, cadmium and zinc sulfide leaching. Recently developed bioremediation methods and biosorption technologies have shown a good potential for industrial applications to remove trace heavy metal and radionuclide concentrations from contaminated soils, and mining and processing effluents.

  1. Mineral facilities of Northern and Central Eurasia

    Science.gov (United States)

    Baker, Michael S.; Elias, Nurudeen; Guzman, Eric; Soto-Viruet, Yadira

    2010-01-01

    This map displays almost 900 records of mineral facilities within the countries that formerly constituted the Union of Soviet Socialist Republics (USSR). Each record represents one commodity and one facility type at a single geographic location. Facility types include mines, oil and gas fields, and plants, such as refineries, smelters, and mills. Common commodities of interest include aluminum, cement, coal, copper, gold, iron and steel, lead, nickel, petroleum, salt, silver, and zinc. Records include attributes, such as commodity, country, location, company name, facility type and capacity (if applicable), and latitude and longitude geographical coordinates (in both degrees-minutes-seconds and decimal degrees). The data shown on this map and in table 1 were compiled from multiple sources, including (1) the most recently available data from the U.S. Geological Survey (USGS) Minerals Yearbook (Europe and Central Eurasia volume), (2) mineral statistics and information from the USGS Minerals Information Web site (http://minerals.usgs.gov/minerals/pubs/country/europe.html), and (3) data collected by the USGS minerals information country specialists from sources, such as statistical publications of individual countries, annual reports and press releases of operating companies, and trade journals. Data reflect the most recent published table of industry structure for each country at the time of this publication. Additional information is available from the country specialists listed in table 2

  2. Situation Reports--Afghanistan, Cyprus, Iran, Kenya, Lebanese Republic, Malagasy Republic, Malaysia (West), People's Democratic Republic of Yemen.

    Science.gov (United States)

    International Planned Parenthood Federation, London (England).

    Data relating to population and family planning in eight foreign countries are presented in these situation reports. Countries included are Afghanistan, Cyprus, Iran, Kenya, Lebanese Republic, Malagasy Republic (Madagascar), Malaysia (West), and People's Democratic Republic of Yemen. Information is provided under two topics, general background and…

  3. The Aspergillus niger growth on the treated concrete substrate using variable antifungals

    Science.gov (United States)

    Parjo, U. K.; Sunar, N. M.; Leman, A. M.; Gani, P.; Embong, Z.; Tajudin, S. A. A.

    2016-11-01

    The aim of this study was to evaluate the Aspergillus niger (A. niger) growth on substrates after incorporates with different compounds of antifungals which is normally used in food industry. The antifungals named as potassium sorbate (PS), calcium benzoate (CB) and zinc salicylate (ZS) were applied on concrete substrate covered with different wall finishing such as acrylic paint (AP), glycerol based paint (GBP), thin wallpaper (THIN) and thick wallpaper (THICK). The concrete substrate were inoculated with spore suspension, incubated at selected temperature (30oC) and relative humidity (90%)in plant growth chamber. The observations were done from the Day 3 until Day 27. The results showed that the growth of the A. niger for concrete treated by PS for AP, GBP, THIN, and THICK were 64%, 32%, 11% and 100%, respectively. Meanwhile for CB, the growth of A. niger on AP, GBP, THIN, and THICK were 100%, 12%, 41%, and 13%, respectively. Similarly, treated concrete by ZS revealed that the growth of A. niger on the same substrate cover were 33%, 47%, 40%, and 39%, respectively. The results obtained in this study provide a valuable knowledge on the abilities of antifungals to remediate A. niger that inoculated on the concrete substrate. Consequently, this study proved that the PS covering with THIN more efficiency compares CB and ZS to prevent A. niger growth.

  4. Central African Republic.

    Science.gov (United States)

    1989-11-01

    The Central African Republic contains 242,000 square miles, which rolling terrain almost 2000 feet above sea level. The climate is tropical, and it has a population of 2.8 million people with a 2.5% growth rate. There are more than 80 ethnic groups including Baya 34%, Banda 28%, Sara 10%, Mandja 9%, Mboum 9%, and M'Baka 7%. The religions are traditional African 35%, protestant 25%, Roman Catholic 25%, and Muslim 15%, and the languages are French and Sangho. The infant mortality rate is 143/1000, with expectancy at 49 years and a 40% literacy rate. The work force of 1 million is 70% agricultural, industry 6% and commerce and service 6% and government 3%. The government consists of a president assisted by cabinet ministers and a single party. Natural resources include diamonds, uranium, timber, gold, and oil, and major industries are beverages, textiles, and soap. Agricultural products feature coffee, cotton, peanuts, tobacco, food crops and livestock. Most of the population live in rural areas and most of the 80 ethnic groups have their own language. This is one of the world's least developed countries, with a per capita income of $375/year. The main problems with development are the poor transportation infrastructure, and the weak internal and international marketing systems. The US and various international organizations have aided in agriculture development, health programs, and family planning. US investment is mainly in diamond and gold mining, and although oil drilling has been successful it is not economically feasible at current prices.

  5. AIR CONDITIONING IN MINES IN THE CZECH REPUBLIC AND UKRAINE

    Directory of Open Access Journals (Sweden)

    Pavel Zapletal

    2014-07-01

    Full Text Available The present-day micro-climatic conditions in black coal mines are of such nature that in no mine natural micro-climate conditioning is sufficient any more. The original temperature of rocks grows progressively in dependence on the increasing depth of the extracted seam, or more precisely, on the mining workplace, and this growth is much more significant than previously considered. The temperature of the surrounding rocks, but also high-performance continuous miners and conveyor belt drives heat up airflow, thus worsening microclimatic conditions. This article describes micro-climatic conditions the in Czech Republic and Ukraine and some methods of deep mines air conditioning.

  6. The Constitution of the Republic of Estonia

    Index Scriptorium Estoniae

    2009-01-01

    Sisaldab ka: The Constitution of the Republic of Estonia Amendment Act. The Constitution of the Republic of Estonia Implementation Act. Act to Amend the Constitution of the Republic of Estonia for Election of Local Government Councils for Term of Four Years

  7. The Constitution of the Republic of Estonia

    Index Scriptorium Estoniae

    2005-01-01

    Raamat sisaldab ka: The Constitution of the Republic of Estonia amendment act ; The Constitution of the Republic of Estonia implementation act ; Act to amend the Constitution of the Republic of Estonia for election of local government councils for term of four years

  8. The Constitution of the Republic of Estonia

    Index Scriptorium Estoniae

    2009-01-01

    Sisaldab ka: The Constitution of the Republic of Estonia Amendment Act. The Constitution of the Republic of Estonia Implementation Act. Act to Amend the Constitution of the Republic of Estonia for Election of Local Government Councils for Term of Four Years

  9. The Constitution of the Republic of Estonia

    Index Scriptorium Estoniae

    2005-01-01

    Raamat sisaldab ka: The Constitution of the Republic of Estonia amendment act ; The Constitution of the Republic of Estonia implementation act ; Act to amend the Constitution of the Republic of Estonia for election of local government councils for term of four years

  10. Characterization of clay minerals; Caracterizacion de minerales arcillosos

    Energy Technology Data Exchange (ETDEWEB)

    Diaz N, C.; Olguin, M.T.; Solache R, M.; Alarcon H, T.; Aguilar E, A. [Gerencia de Ciencias Basicas, Direccion de Investigacion Cientifica, Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2002-07-01

    The natural clays are the more abundant minerals on the crust. They are used for making diverse industrial products. Due to the adsorption and ion exchange properties of these, a great interest for developing research directed toward the use of natural clays for the waste water treatment has been aroused. As part of such researches it is very important to carry out previously the characterization of the interest materials. In this work the results of the mineral and elemental chemical composition are presented as well as the morphological characteristics of clay minerals from different regions of the Mexican Republic. (Author)

  11. AMYLASE PRODUCTION BY ASPERGILLUS NIGER UNDER SOLID STATE FERMENTATION USING AGROINDUSTRIAL WASTES

    Directory of Open Access Journals (Sweden)

    Suganthi

    2011-02-01

    Full Text Available Solid state fermentation holds tremendous potentials for the production of the enzyme amylase by Aspergillus niger. Different solid substrates like rice bran, wheat bran, black gram bran, coconut oil cake, gingely oil cake and groundnut oil cake are rich in starch. These agro industrial residues are cheap raw materials for amylase production. Aspergillus niger BAN3E was identified to be the best producer of amylase. When A. niger BAN3E was incubated for 6 days at 37°C it showed high yield of amylase in groundnut oil cake substratein solid state fermentation. Sucrose and nitrogen improved the yield in the same medium.

  12. Hydrothermal minerals

    Digital Repository Service at National Institute of Oceanography (India)

    Nath, B.N.

    -floor hydrothermal processes involving free circulation of seawater through ocean crust as convection. Heat flow, seafloor fracturing, permeability and fluid composition are the parameters governing the type and extent of mineralization. The chimney like... stream_size 23365 stream_content_type text/plain stream_name Refresher_Course_Mar_Geol_Geophys_2007_Lecture_Notes_78.pdf.txt stream_source_info Refresher_Course_Mar_Geol_Geophys_2007_Lecture_Notes_78.pdf.txt Content-Encoding UTF-8...

  13. In-silico analysis of Aspergillus niger beta-glucosidases

    Science.gov (United States)

    Yeo S., L.; Shazilah, K.; Suhaila, S.; Abu Bakar F., D.; Murad A. M., A.

    2014-09-01

    Genomic data mining was carried out and revealed a total of seventeen β-glucosidases in filamentous fungi Aspergillus niger. Two of them belonged to glycoside hydrolase family 1 (GH1) while the rest belonged to genes in family 3 (GH3). These proteins were then named according to the nomenclature as proposed by the International Union of Biochemistry (IUB), starting from the lowest pI and glycoside hydrolase family. Their properties were predicted using various bionformatic tools showing the presence of domains for signal peptide and active sites. Interestingly, one particular domain, PA14 (protective antigen) was present in four of the enzymes, predicted to be involved in carbohydrate binding. A phylogenetic tree grouped the two glycoside hydrolase families with GH1 and GH3 related organisms. This study showed that the various domains present in these β-glucosidases are postulated to be crucial for the survival of this fungus, as supported by other analysis.

  14. Groundwater quality assessment in parts of Eastern Niger Delta, Nigeria

    Science.gov (United States)

    Edet, A. E.

    1993-09-01

    Hydrogeochemical analyses were carried out on groundwater samples collected from 20 producing wells in different parts of the Eastern Niger Delta. Results show that the concentrations of the major cations (Na+, K+, Ca2+, Mg2+) and anions (Cl-, SO{4/2-}, HCO{3/-}) are below the World Health Organization (WHO) standards set for domestic purposes. The occurrence of slightly saline water in certain areas is attributed to local hydrogeological processes occurring in the area. On the basis of the analytical results, two hydrogeochemical facies are delineated. These are calcium-magnesium-chloride-sulfate-bicarbonate (Ca-Mg-Cl-SO4-HCO3) and calcium-sodium-chloride-sulfatebicarbonate (Ca-Na-Cl-SO4-HCO3) to the west and east of the study area, respectively.

  15. On river cross-sectional change in the Niger Delta

    Science.gov (United States)

    Abam, T. K. S.; Omuso, W. O.

    2000-08-01

    A network of dominantly distributary river systems dissects the superficial deposits of the Niger Delta comprising alluvial sediments. Changes in river cross-sections are instigated mainly by bank failures, fluctuations in discharge, and bed degradation by fluvial processes. The relative importance of factors causing river cross-sectional change was ranked, based on a deterministic sensitivity technique involving partial differentiation of soil properties, flow characteristics, and geometrical parameters of the river channels. Analysis suggests that steep bank inclination and high flow velocity/discharge are the major causes of cross-sectional change, while interlocking of soil grains is the major erosion-restraining factor. Sensitivity coefficients were used further to generate susceptibility indices, indicating the vulnerability of channel cross-sections to change. Based on this, the risks of channel cross-sectional change were compared at different sites.

  16. Catalytical Properties of Free and Immobilized Aspergillus niger Tannase

    Directory of Open Access Journals (Sweden)

    Abril Flores-Maltos

    2011-01-01

    Full Text Available A fungal tannase was produced, recovered, and immobilized by entrapment in calcium alginate beads. Catalytical properties of the immobilized enzyme were compared with those of the free one. Tannase was produced intracellularly by the xerophilic fungus Aspergillus niger GH1 in a submerged fermentation system. Enzyme was recovered by cell disruption and the crude extract was partially purified. The catalytical properties of free and immobilized tannase were evaluated using tannic acid and methyl gallate as substrates. KM and Vmax values for free enzyme were very similar for both substrates. But, after immobilization, KM and Vmax values increased drastically using tannic acid as substrate. These results indicated that immobilized tannase is a better biocatalyst than free enzyme for applications on liquid systems with high tannin content, such as bioremediation of tannery or olive-mill wastewater.

  17. INSPECTIVE AND HYGIENIC-SANITARY EVALUATIONS ON Centrolophus niger

    Directory of Open Access Journals (Sweden)

    G. Ziino

    2009-12-01

    Full Text Available A preliminary study was carried on n. 11 specimens of Centrolophus niger fished along Ionian coastlines in province of Catania and Siracusa (Sicily in order to determine sensory parameters and hygienic characteristics after 0, 3 and 5 days of storage at 3±1°C as well as the chemical composition and nutritional value. An increase of Mesophilic aerobic plate count and specific spoilage organism number was observed in skill and gill samples. Frequently gut contamination was very low. In all samples Echinophallus wageneri and Amphicotyle heteropleura were found in the pyloric caeca. The muscle was particularly rich in proteins (15.41%, poor in lipids (1.28% and with a good correlation between w3/w6 fatty acids.

  18. Microbial abatement of toluene using Aspergillus niger in upflow bioreactor.

    Science.gov (United States)

    Gopinath, M; Mohanapriya, C; Sivakumar, K; Baskar, G; Muthukumaran, C; Dhanasekar, R

    2016-12-01

    Microbial abatement of toluene using Aspergillus niger in coir packed upflow bioreactor was investigated in this study. Toluene degrading microbes were isolated from municipal sewage effluent and identified by 16s rRNA sequencing method. The microbes were cultured in 2% (v/v) toluene input per day, which exhibited 95% removal efficiency with the kinetic correction value (R(2)) of 0.9024 at the optimum flow rate of about 0.4m(3)h(-1). Various parameters such as effect of flow rate, column height, elimination capacity and EBRT with removal efficiency for 50 day cycle were also optimized. The plug flow model for toluene degradation was properly expressed and the Monod kinetics constant Km and rmax values were determined as 2.25gm(-3) and 67.773gm(-3)h(-1) respectively for microbial growth rate. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. [Pollution of the groundwater in the city of Niamey, Niger].

    Science.gov (United States)

    Chippaux, J P; Houssier, S; Gross, P; Bouvier, C; Brissaud, F

    2002-06-01

    We conducted a study on chemical and bacteriological groundwater pollution in Niamey, a Sahelian city of some 700,000 inhabitants. A total of 22 wells and 24 bore-holes were selected on a geological and socio-economic basis. The superficial aquifers, located on each bank of the River Niger and connected to the wells, presented high levels of oxidizable nitrogen and bacteriological pollution (coliform and faecal Streptococcus) which make the water unfit for human consumption. The deep aquifer, which supplies pumps, was also polluted but to a lesser degree. Faecal pollution increased after the rainy season. The lack of sanitation in Niamey and the seepage of polluted matters from the superficial layers could explain this pollution. Eventually, the use of the groundwater could increase and constitute a major health risk for the majority of the inhabitants of Niamey.

  20. A new diketopiperazine heterodimer from an endophytic fungus Aspergillus niger.

    Science.gov (United States)

    Li, Xiao-Bin; Li, Yue-Lan; Zhou, Jin-Chuan; Yuan, Hui-Qing; Wang, Xiao-Ning; Lou, Hong-Xiang

    2015-01-01

    One new diketopiperazine heterodimer, asperazine A (1), and eight known compounds, asperazine (2), cyclo(d-Phe-l-Trp) (3), cyclo(l-Trp-l-Trp) (4), 4-(hydroxymethyl)-5,6-dihydro-pyran-2-one (5), walterolactone A (6), and campyrones A-C (7-9), were isolated from an endophytic fungus Aspergillus niger. Their structures were determined unequivocally on the basis of extensive spectroscopic data analysis. This is the first report of the presence of compound 3 as a natural product. Cytotoxicity test against human cancer cell lines PC3, A2780, K562, MBA-MD-231, and NCI-H1688 revealed that compounds 1 and 2 had weak activities.

  1. Outcome of teenage pregnancy in the niger delta of Nigeria.

    Science.gov (United States)

    Ayuba, Ibrahim Isa; Gani, Owoeye

    2012-03-01

    Young maternal age at delivery has been proposed as risk factor for adverse pregnancy outcome, it occurs in all races, faiths, socioeconomic statuses, and regions. Teenage pregnancy can have serious physical consequences and teenage mothers are likely to be unmarried, poor and remain uneducated. The objective of the study was to evaluate risk factors associated with teenage pregnancy and compare the obstetric and fetal outcome to older parturient. This is a retrospective study performed over a period of 4 Years (January 1, 2007 to December 31, 2010) in Niger Delta University Teaching Hospital Bayelsa State, Nigeria where data was retrieved from the hospital records. All teenage mothers (aged 13-19) who had delivery within the period were compared with 180 randomly selected deliveries in the older age group (20-32 years) over the same period. Variables of interest were the demographic characteristics of the women, their obstetric complications and the outcome. There were a total of 1341 deliveries during the study period, out which 83(6.2%) were teenagers. Teenage mothers were significantly more likely to be unbooked, (p = 0.000) Unmarried, (χ=26.2; p = 0.000) had significantly more preterm labor, (P=0.000) and Caesarean sections (P= 0.014). However, there was no difference in both the perinatal and maternal mortality rates between the two groups. Teenage pregnancy in the Niger Delta is concentrated among women with less formal education, who are unemployed, unmarried and with inadequate antenatal care and obstetric risks for poor pregnancy outcome. The provision an appropriate contraceptive method and to look with priority after any pregnancy occurring among this age group cannot be overemphasized.

  2. The effects of juvenile hormone on Lasius niger reproduction.

    Science.gov (United States)

    Pamminger, T; Buttstedt, A; Norman, V; Schierhorn, A; Botías, C; Jones, J C; Basley, K; Hughes, W O H

    2016-12-01

    Reproduction has been shown to be costly for survival in a wide diversity of taxa. The resulting trade-off, termed the reproduction-survival trade-off, is thought to be one of the most fundamental forces of life-history evolution. In insects the pleiotropic effect of juvenile hormone (JH), antagonistically regulating reproduction and pathogen resistance, is suggested to underlie this phenomenon. In contrast to the majority of insects, reproductive individuals in many eusocial insects defy this trade-off and live both long and prosper. By remodelling the gonadotropic effects of JH in reproductive regulation, the queens of the long-lived black garden ant Lasius niger (living up to 27 years), have circumvented the reproduction-survival trade off enabling them to maximize both reproduction and pathogen resistance simultaneously. In this study we measure fertility, vitellogenin gene expression and protein levels after experimental manipulation of hormone levels. We use these measurements to investigate the mechanistic basis of endocrinological role remodelling in reproduction and determine how JH suppresses reproduction in this species, rather then stimulating it, like in the majority of insects. We find that JH likely inhibits three key aspects of reproduction both during vitellogenesis and oogenesis, including two previously unknown mechanisms. In addition, we document that juvenile hormone, as in the majority of insects, has retained some stimulatory function in regulating vitellogenin expression. We discuss the evolutionary consequences of this complex regulatory architecture of reproduction in L. niger, which might enable the evolution of similar reproductive phenotypes by alternate regulatory pathways, and the surprising flexibility regulatory role of juvenile hormone in this process.

  3. Review of the Federal Mining Law. [German Federal Republic

    Energy Technology Data Exchange (ETDEWEB)

    Weller, H.

    1981-01-01

    The Federal Mining Law is a codification of mining law in the Federal Republic of Germany. It contains 178 paragraphs covering all aspects of prospecting and mining of mineral raw materials and related activities. The new law is to replace the former regional mining laws as well as most of the former Federal and regional regulations. All in all, 104 laws and regulations are repealed in sections 174 and 175. Basic principles of the former mining laws have been adhered to, e.g. mineral reserves do not come under the proprietory rights of the land owner, preventive monitoring of operations by means of operation plans, cession of territory under mining law, and the regulations concerning mining and land ownership. However, there are new details in the Federal Mining Law, in particular with regard to concessions and mining damage; this is reflected in a more complicated legal language.

  4. Evaluating farmers’ adaptation strategies to climate change: A case study of Kaou local government area, Tahoua State, Niger Republic

    Directory of Open Access Journals (Sweden)

    A. Moussa Tabbo

    2016-03-01

    Full Text Available The study discusses local farmers’ strategies of coping with and building resilience against the negative impact of climate change. Information for the discussion was from data collected using a set of structured questionnaires from interviews scheduled with 128 farmers. The questionnaire was based on previous literature and direct reconnaissance interview with farmers, which culminated in 13 strategies used for the study being reported. For each question, respondents were asked to choose their best and worst strategies. Thus, the difference between the best and worst strategies consistent with random utility theory has been used for the modelling. Results show that semi-transhumance, various handicrafts making, rural migration, small-scale vegetable production and small-scale river exploitation were the most important strategies identified, whilst water transport and vending, shifting cultivation, gypsum mining, gathering and trading of wild fruits and edible plants as well as cattle and sheep fattening were the least appreciated strategies identified amongst the farmers facing climate change. These findings are therefore imperative for planning farmers’ capacity-building and resilience against climate change projects to ensure sustainability in the study area.Keywords: Farmers’ adaptation strategies; Climate change resilience; Kaou

  5. A SIMPLE ANALYTICAL MODEL FOR PREDICTING SAND PRODUCTION IN A NIGER DELTA OIL FIELD

    Directory of Open Access Journals (Sweden)

    Isehunwa S.O

    2010-09-01

    Full Text Available Sand production, which is predominant in the Niger Delta, is a growing concern in the petroleum industry because of the associated technical, operational and economic challenges. The development of sanding predictive tools and effective management strategies has received much attention in literature. However, most of the publishedtheoretical models have been validated with laboratory or data obtained from petroleum provinces other than the Niger Delta. This work developed a simple analytical model for predicting sand production and validated it using 16 wells in a Niger Delta Field. The results confirmed the well-known impact of flow rate, fluid viscosity and grain size and density on sanding rates. It was also observed that at moderate production rates, sanding in the Niger Delta Field has relatively small arch lengths of below 30 feet.

  6. Gene deletion of cytosolic ATP: citrate lyase leads to altered organic acid production in Aspergillus niger

    DEFF Research Database (Denmark)

    Meijer, Susan Lisette; Nielsen, Michael Lynge; Olsson, Lisbeth

    2009-01-01

    With the availability of the genome sequence of the filamentous fungus Aspergillus niger, the use of targeted genetic modifications has become feasible. This, together with the fact that A. niger is well established industrially, makes this fungus an attractive micro-organism for creating a cell...... factory platform for production of chemicals. Using molecular biology techniques, this study focused on metabolic engineering of A. niger to manipulate its organic acid production in the direction of succinic acid. The gene target for complete gene deletion was cytosolic ATP: citrate lyase (acl), which...... the acl gene. Additionally, the total amount of organic acids produced in the deletion strain was significantly increased. Genome-scale stoichiometric metabolic model predictions can be used for identifying gene targets. Deletion of the acl led to increased succinic acid production by A. niger....

  7. Toolkit for visualization of the cellular structure and organelles in Aspergillus niger.

    Science.gov (United States)

    Buren, Emiel B J Ten; Karrenbelt, Michiel A P; Lingemann, Marit; Chordia, Shreyans; Deng, Ying; Hu, JingJing; Verest, Johanna M; Wu, Vincen; Gonzalez, Teresita J Bello; Heck, Ruben G A van; Odoni, Dorett I; Schonewille, Tom; Straat, Laura van der; Graaff, Leo H de; Passel, Mark W J van

    2014-12-19

    Aspergillus niger is a filamentous fungus that is extensively used in industrial fermentations for protein expression and the production of organic acids. Inherent biosynthetic capabilities, such as the capacity to secrete these biomolecules in high amounts, make A. niger an attractive production host. Although A. niger is renowned for this ability, the knowledge of the molecular components that underlie its production capacity, intercellular trafficking processes and secretion mechanisms is far from complete. Here, we introduce a standardized set of tools, consisting of an N-terminal GFP-actin fusion and codon optimized eforRed chromoprotein. Expression of the GFP-actin construct facilitates visualization of the actin filaments of the cytoskeleton, whereas expression of the chromoprotein construct results in a clearly distinguishable red phenotype. These experimentally validated constructs constitute the first set of standardized A. niger biomarkers, which can be used to study morphology, intercellular trafficking, and secretion phenomena.

  8. Review of secondary metabolites and mycotoxins from the Aspergillus niger group

    DEFF Research Database (Denmark)

    Nielsen, Kristian Fog; Mogensen, Jesper Mølgaard; Johansen, Maria

    2009-01-01

    Filamentous fungi in the Aspergillus section Nigri (the black aspergilli) represent some of the most widespread food and feed contaminants known but they are also some of the most important workhorses used by the biotechnological industry. The Nigri section consists of six commonly found species...... (excluding A. aculeatus and its close relatives) from which currently 145 different secondary metabolites have been isolated and/or detected. From a human and animal safety point of view, the mycotoxins ochratoxin A (from A. carbonarius and less frequently A. niger) and fumonisin B2 (from A. niger...... since it is consistently produced by A. tubingensis (177 of 177 strains tested) and A. acidus (47 of 47 strains tested) but never by A. niger (140 strains tested). Naptho-γ-pyrones are the compounds produced in the highest quantities and are produced by all six common species in the group (A. niger 134...

  9. Enantioselective accumulation of (--)-pinoresinol through O-demethylation of (+/-)-eudesmin by Aspergillus niger.

    Science.gov (United States)

    Kasahara, H; Miyazawa, M; Kameoka, H

    1997-04-01

    Microbial transformation of (+/-)-eudesmin by Aspergillus niger was investigated. Enantioselective accumulation of (--)-pinoresinol was shown through O-demethylation of (+/-)-eudesmin. This fungus O- demethylated both enantiomers of eudesmin, but the conversion rates for each enantiomer were clearly different.

  10. Oil, gender and agricultural child labour in the Niger Delta region of ...

    African Journals Online (AJOL)

    ... violent conflicts, crimes, rural-urban migration, environmental degradation, ... The relationship between household size and agricultural child labour and ... Keywords: Gender, Agricultural child labour, Niger Delta, Poverty, Oil, Multinationals.

  11. Socio-Economic Impacts of Oil Development in the Niger- Delta ...

    African Journals Online (AJOL)

    Socio-Economic Impacts of Oil Development in the Niger- Delta, Nigeria. ... oil companies should involve the communities in the development process and develop ... in these activities would sustainable and peaceful development be possible.

  12. Assessment of heavy metal speciation in soils impacted with crude oil in the Niger Delta, Nigeria

    National Research Council Canada - National Science Library

    Iwegbue, Chukwujindu M.A

    2011-01-01

    Chemical fractionation of Cd, Cu, Pb, Ni, Cr, Zn and Mn in soils that had received a significant impact of crude oil spillage in the Niger Delta, Nigeria was studied using a sequential chemical extraction method...

  13. Rewiring a secondary metabolite pathway towards itaconic acid production in Aspergillus niger

    NARCIS (Netherlands)

    Hossain, A.H.; Li, A.; Brickwedde, A.; Wilms, L.; Caspers, M.; Overkamp, K.; Punt, P.J.

    2016-01-01

    Background: The industrially relevant filamentous fungus Aspergillus niger is widely used in industry for its secretion capabilities of enzymes and organic acids. Biotechnologically produced organic acids promise to be an attractive alternative for the chemical industry to replace petrochemicals.

  14. The role of analytical chemistry in Niger Delta petroleum exploration: a review.

    Science.gov (United States)

    Akinlua, Akinsehinwa

    2012-06-12

    Petroleum and organic matter from which the petroleum is derived are composed of organic compounds with some trace elements. These compounds give an insight into the origin, thermal maturity and paleoenvironmental history of petroleum, which are essential elements in petroleum exploration. The main tool to acquire the geochemical data is analytical techniques. Due to progress in the development of new analytical techniques, many hitherto petroleum exploration problems have been resolved. Analytical chemistry has played a significant role in the development of petroleum resources of Niger Delta. Various analytical techniques that have aided the success of petroleum exploration in the Niger Delta are discussed. The analytical techniques that have helped to understand the petroleum system of the basin are also described. Recent and emerging analytical methodologies including green analytical methods as applicable to petroleum exploration particularly Niger Delta petroleum province are discussed in this paper. Analytical chemistry is an invaluable tool in finding the Niger Delta oils.

  15. COFFEE BEAN MYCO-CONTAMINANTS AND OXALIC ACID PRODUCING ASPERGILLUS NIGER

    Directory of Open Access Journals (Sweden)

    Mohamed A. Yassin

    2015-03-01

    Full Text Available Coffee bean-contaminating fungi were determined in random samples collected in Riyadh, Kingdom of Saudi Arabia, using the direct plating technique. Forty-five samples were examined and 12 fungal species belonging to 5 genera were isolated. Aspergillus niger was the most widely distributed and most frequently isolated fungus (86.67%. The ability of the predominant fungus, A. niger, to produce oxalic acid was evaluated using high-performance liquid chromatography. About 50% of the tested A. niger isolates produced oxalic acid; the amount produced was in the range of 90–550 ppm of oxalic acid. Because A. niger was the predominant and most widely distributed toxigenic fungus in the examined samples, more efforts should be directed to minimize the risk of oxalic acid contamination of commoditized coffee beans in the Kingdom of Saudi Arabia.

  16. Inhibition of oxidative phosphorylation for enhancing citric acid production by Aspergillus niger

    OpenAIRE

    Wang, Lu; Zhang, Jianhua; Cao, Zhanglei; Wang, Yajun; Gao, Qiang; Zhang, Jian; Wang, Depei

    2015-01-01

    Background The spore germination rate and growth characteristics were compared between the citric acid high-yield strain Aspergillus niger CGMCC 5751 and A. niger ATCC 1015 in media containing antimycin A or DNP. We inferred that differences in citric acid yield might be due to differences in energy metabolism between these strains. To explore the impact of energy metabolism on citric acid production, the changes in intracellular ATP, NADH and NADH/NAD+ were measured at various fermentation s...

  17. Collective violence and attitudes of women toward intimate partner violence: Evidence from the Niger Delta

    OpenAIRE

    Antai Diddy; Antai Justina

    2009-01-01

    Abstract Background The Niger Delta region of Nigeria has been undergoing collective violence for over 25 years, which has constituted a major public health problem. The objectives of this study were to investigate the predictors of women's attitudes toward intimate partner violence in the Niger Delta in comparison to that of women in other parts of Nigeria. Methods The 2003 Nigeria Demographic and Health Survey was used for this study. Respondents were selected using a stratified two-stage c...

  18. Invasive Aspergillus niger complex infections in a Belgian tertiary care hospital.

    Science.gov (United States)

    Vermeulen, E; Maertens, J; Meersseman, P; Saegeman, V; Dupont, L; Lagrou, K

    2014-05-01

    The incidence of invasive infections caused by the Aspergillus niger species complex was 0.043 cases/10 000 patient-days in a Belgian university hospital (2005-2011). Molecular typing was performed on six available A. niger complex isolates involved in invasive disease from 2010 to 2011, revealing A. tubingensis, which has higher triazole minimal inhibitory concentrations, in five out of six cases.

  19. Mobiles and mobility: The Effect of Mobile Phones on Migration in Niger

    OpenAIRE

    Aker, Jenny C.; Clemens, Michael A.; Ksoll, Christopher

    2011-01-01

    Labor markets in developing countries are subject to a high degree of frictions. We report the results from a randomized evaluation of an adult education program (Project ABC) in Niger, in which students learned how to use simple mobile phones as part of a literacy and numeracy class. Overall, our preliminary results suggest that access to this technology substantially influenced seasonal migration in Niger, increasing the likelihood of migration by at least one household member by 7 percenta...

  20. Sand Failure Mechanism and Sanding Parameters in Niger Delta Oil Reservoirs

    OpenAIRE

    Sunday Isehunwa,; Andrew Farotade

    2010-01-01

    Sand production is a major issue during oil and gas production from unconsolidated reservoirs. In predicting the onset of sand production, it is important to accurately determine the failure mechanism and the contributing parameters. The aim of this study was to determine sand failure mechanism in the Niger-Delta, identify themajor contributing parameters and evaluate their effects on sanding.Completion and production data from 78 strings completed on 22 reservoirs in a Niger Delta oil Field ...

  1. Differential cytotoxic properties of Helleborus niger L. on tumour and immunocompetent cells.

    Science.gov (United States)

    Schink, Michael; Garcia-Käufer, Manuel; Bertrams, Julia; Duckstein, Sarina M; Müller, Margit B; Huber, Roman; Stintzing, Florian C; Gründemann, Carsten

    2015-01-15

    In Romanian folk medicine, Helleborus niger L. is used for the treatment of rheumatoid arthritis or viral infections and in complementary therapy, especially in anthroposophic medicine (AM), where the plant is administered as an adjuvant to treat malignant diseases. In the present study, we investigated the differential cytotoxic effects of H. niger on human tumour and healthy cells of the human immune system in vitro. Protoanemonin and saponins, as significant constituents of H. niger extracts, were quantified in five individual batches using validated HPLC methods. Further, the impact of H. niger on proliferation capacity (MTT assay) as well as on apoptosis and necrosis induction in a panel of tumour cell lines and human lymphocytes (combined annexin V and propidium iodide staining) was monitored. In addition, NK cell function (degranulation-CD107a assay and IFN-gamma secretion) was also investigated since these immunocompetent cells are important for the control of malignancies within the human body. Extracts of H. niger induced proliferation inhibition not only of lymphoblastic leukaemia cells (MOLT4; IC50: 171 µg/mL) but also of myosarcoma (SK-UT-1b; IC50: 304 µg/mL) and melanoma cells (HT-144; IC50: 569 µg/mL) due to the induction of apoptosis. Purified T cells or NK cells were significantly affected through the presence of high H. niger concentrations while bulk lymphocytes were not affected. NK cells' anti-tumour functions expressed by degranulation capacity as well as IFN-y production were unaffected by the presence of the H. niger extract. Since protoanemonin and saponins have been reported in the literature to exert cytotoxic effects, their content was also determined. H. niger extracts exhibit differential cytotoxicity towards tumour cell lines and healthy human T- and NK-cells. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  2. [Construction and application of black-box model for glucoamylase production by Aspergillus niger].

    Science.gov (United States)

    Li, Lianwei; Lu, Hongzhong; Xia, Jianye; Chu, Ju; Zhuang, Yingping; Zhang, Siliang

    2015-07-01

    Carbon-limited continuous culture was used to study the relationship between the growth of Aspergillus niger and the production of glucoamylase. The result showed that when the specific growth rate was lower than 0.068 h(-1), the production of glucoamylase was growth-associated, when the specific growth rate was higher than 0.068 h(-1), the production of glucoamylase was not growth-associated. Based on the result of continuous culture, the Monod dynamics model of glucose consumption of A. niger was constructed, Combining Herbert-Pirt equation of glucose and oxygen consumption with Luedeking-Piret equation of enzyme production, the black-box model of Aspergillus niger for enzyme production was established. The exponential fed-batch culture was designed to control the specific growth rate at 0.05 h(-1) by using this model and the highest yield for glucoamylase production by A. niger reached 0.127 g glucoamylase/g glucose. The black-box model constructed in this study successfully described the glucoamylase production by A. niger and the result of the model fitted the measured value well. The black-box model could guide the design and optimization of glucoamylase production by A. niger.

  3. Autophagy promotes survival in aging submerged cultures of the filamentous fungus Aspergillus niger.

    Science.gov (United States)

    Nitsche, Benjamin M; Burggraaf-van Welzen, Anne-Marie; Lamers, Gerda; Meyer, Vera; Ram, Arthur F J

    2013-09-01

    Autophagy is a well-conserved catabolic process constitutively active in eukaryotes that is involved in maintaining cellular homeostasis by the targeting of cytoplasmic content and organelles to vacuoles. Autophagy is strongly induced by the limitation of nutrients including carbon, nitrogen, and oxygen and is clearly associated with cell death. It has been demonstrated that the accumulation of empty hyphal compartments and cryptic growth in carbon-starved submerged cultures of the filamentous fungus Aspergillus niger is accompanied by a joint transcriptional induction of autophagy genes. This study examines the role of autophagy by deleting the atg1, atg8, and atg17 orthologs in A. niger and phenotypically analyzing the deletion mutants in surface and submerged cultures. The results indicate that atg1 and atg8 are essential for efficient autophagy, whereas deletion of atg17 has little to no effect on autophagy in A. niger. Depending on the kind of oxidative stress confronted with, autophagy deficiency renders A. niger either more resistant (menadione) or more sensitive (H2O2) to oxidative stress. Fluorescence microscopy showed that mitochondrial turnover upon carbon depletion in submerged cultures is severely blocked in autophagy-impaired A. niger mutants. Furthermore, automated image analysis demonstrated that autophagy promotes survival in maintained carbon-starved cultures of A. niger. Taken together, the results suggest that besides its function in nutrient recycling, autophagy plays important roles in physiological adaptation by organelle turnover and protection against cell death upon carbon depletion in submerged cultures.

  4. Effect of different polyphenol sources on the efficiency of ellagic acid release by Aspergillus niger.

    Science.gov (United States)

    Sepúlveda, Leonardo; de la Cruz, Reynaldo; Buenrostro, José Juan; Ascacio-Valdés, Juan Alberto; Aguilera-Carbó, Antonio Francisco; Prado, Arely; Rodríguez-Herrera, Raúl; Aguilar, Cristóbal Noé

    2016-01-01

    Fungal hydrolysis of ellagitannins produces hexahydroxydiphenic acid, which is considered an intermediate molecule in ellagic acid release. Ellagic acid has important and desirable beneficial health properties. The aim of this work was to identify the effect of different sources of ellagitannins on the efficiency of ellagic acid release by Aspergillus niger. Three strains of A. niger (GH1, PSH and HT4) were assessed for ellagic acid release from different polyphenol sources: cranberry, creosote bush, and pomegranate used as substrate. Polyurethane foam was used as support for solid-state culture in column reactors. Ellagitannase activity was measured for each of the treatments. Ellagic acid was quantified by high performance liquid chromatography. When pomegranate polyphenols were used, a maximum value of ellagic acid (350.21 mg/g) was reached with A. niger HT4 in solid-state culture. The highest amount of ellagitannase (5176.81 U/l) was obtained at 8h of culture when cranberry polyphenols and strain A. niger PSH were used. Results demonstrated the effect of different polyphenol sources and A. niger strains on ellagic acid release. It was observed that the best source for releasing ellagic acid was pomegranate polyphenols and A. niger HT4 strain, which has the ability to degrade these compounds for obtaining a potent bioactive molecule such as ellagic acid.

  5. Production of Fumonisin B-2 and B-4 by Aspergillus niger on Grapes and Raisins

    DEFF Research Database (Denmark)

    Mogensen, Jesper Mølgaard; Frisvad, Jens Christian; Thrane, Ulf

    2010-01-01

    The recent discovery of fumonisin production in Aspergillus niger, raises concerns about the presence of these mycotoxins in grapes and raisins as well as other commodities where A. niger is a frequent contaminant. Here we investigate the potential production of fumonisins in A. niger cultured...... on grapes and raisins. Sixty-six A. niger, 4 A. tubingensis, and 16 A. acidus strains isolated from raisins were tested for fumonisin production on laboratory media. Neither A. tubingensis nor A. acidus strains produced fumonisins, but 77% of A. niger strains did. None of the strains produced ochratoxin A....... Ten selected fumonisin producing A. niger strains were further able to produce fumonisin B2 and fumonisin B4 on grapes in the range 171−7841 μg fumonisin B2/kg and 14−1157 μg fumonisin B4/kg. Four selected strains were able to produce fumonisin B2 (5−6476 μg/kg) and fumonisin B4 (12−672 μg...

  6. Cloning and Genomic Organization of a Rhamnogalacturonase Gene from Locally Isolated Strain of Aspergillus niger.

    Science.gov (United States)

    Damak, Naourez; Abdeljalil, Salma; Taeib, Noomen Hadj; Gargouri, Ali

    2015-08-01

    The rhg gene encoding a rhamnogalacturonase was isolated from the novel strain A1 of Aspergillus niger. It consists of an ORF of 1.505 kb encoding a putative protein of 446 amino acids with a predicted molecular mass of 47 kDa, belonging to the family 28 of glycosyl hydrolases. The nature and position of amino acids comprising the active site as well as the three-dimensional structure were well conserved between the A. niger CTM10548 and fungal rhamnogalacturonases. The coding region of the rhg gene is interrupted by three short introns of 56 (introns 1 and 3) and 52 (intron 2) bp in length. The comparison of the peptide sequence with A. niger rhg sequences revealed that the A1 rhg should be an endo-rhamnogalacturonases, more homologous to rhg A than rhg B A. niger known enzymes. The comparison of rhg nucleotide sequence from A. niger A1 with rhg A from A. niger shows several base changes. Most of these changes (59 %) are located at the third base of codons suggesting maintaining the same enzyme function. We used the rhamnogalacturonase A from Aspergillus aculeatus as a template to build a structural model of rhg A1 that adopted a right-handed parallel β-helix.

  7. Expression of Lactate Dehydrogenase in Aspergillus niger for L-Lactic Acid Production.

    Science.gov (United States)

    Dave, Khyati K; Punekar, Narayan S

    2015-01-01

    Different engineered organisms have been used to produce L-lactate. Poor yields of lactate at low pH and expensive downstream processing remain as bottlenecks. Aspergillus niger is a prolific citrate producer and a remarkably acid tolerant fungus. Neither a functional lactate dehydrogenase (LDH) from nor lactate production by A. niger is reported. Its genome was also investigated for the presence of a functional ldh. The endogenous A. niger citrate synthase promoter relevant to A. niger acidogenic metabolism was employed to drive constitutive expression of mouse lactate dehydrogenase (mldhA). An appraisal of different branches of the A. niger pyruvate node guided the choice of mldhA for heterologous expression. A high copy number transformant C12 strain, displaying highest LDH specific activity, was analyzed under different growth conditions. The C12 strain produced 7.7 g/l of extracellular L-lactate from 60 g/l of glucose, in non-neutralizing minimal media. Significantly, lactate and citrate accumulated under two different growth conditions. Already an established acidogenic platform, A. niger now promises to be a valuable host for lactate production.

  8. Hypersensitivity testing for Aspergillus fumigatus IgE is significantly more sensitive than testing for Aspergillus niger IgE.

    Science.gov (United States)

    Selvaggi, Thomas A; Walco, Jeremy P; Parikh, Sujal; Walco, Gary A

    2012-02-01

    We sought to determine if sufficient redundancy exists between specific IgE testing for Aspergillus fumigatus and Aspergillus niger to eliminate one of the assays in determining Aspergillus hypersensitivity. We reviewed regional laboratory results comparing A fumigatus-specific IgE with A niger-specific IgE using the Pharmacia UniCAP system (Pharmacia, Kalamazoo, MI). By using the Fisher exact test as an index of concordance among paired results, we showed a significant difference between 109 paired samples for the presence of specific IgE to A fumigatus and A niger (P niger; no specimen was positive for A niger and negative for A fumigatus. We conclude that A fumigatus-specific IgE is sufficient to detect Aspergillus hypersensitivity. The assay for A niger-specific IgE is redundant, less sensitive, and unnecessary if the assay for specific IgE for A fumigatus is performed.

  9. Characterization of a starch-hydrolyzing α-amylase produced by Aspergillus niger WLB42 mutated by ethyl methanesulfonate treatment

    OpenAIRE

    Wang, Shihui; Lin, Chaoyang; Liu, Yun; Shen, Zhicheng; Jeyaseelan, Jenasia; Qin, Wensheng

    2016-01-01

    Aspergillus niger is the most commonly used fungus for commercial amylase production, the increase of amylase activity will be beneficial to the amylase industry. Herein we report a high α-amylase producing (HAP) A. niger WLB42 mutated from A. niger A4 by ethyl methanesulfonate treatment. The fermentation conditions for the amylase production were optimized. The results showed that both the amylase activity and total protein content reached highest after 48-h incubation in liquid medium using...

  10. Phytase production by solid-state fermentation of groundnut oil cake by Aspergillus niger: A bioprocess optimization study for animal feedstock applications.

    Science.gov (United States)

    Buddhiwant, Priyanka; Bhavsar, Kavita; Kumar, V Ravi; Khire, Jayant M

    2016-08-17

    This investigation deals with the use of agro-industrial waste, namely groundnut oil cake (GOC), for phytase production by the fungi Aspergillus niger NCIM 563. Plackett-Burman design (PBD) was used to evaluate the effect of 11 process variables and studies here showed that phytase production was significantly influenced by glucose, dextrin, distilled water, and MgSO4 · 7H2O. The use of response surface methodology (RSM) by Box-Behnken design (BBD) of experiments further enhanced the production by a remarkable 36.67-fold from the original finding of 15 IU/gds (grams of dry substrate) to 550 IU/gds. This is the highest solid-state fermentation (SSF) phytase production reported when compared to other microorganisms and in fact betters the best known by a factor of 2. Experiments carried out using dried fermented koji for phosphorus and mineral release and also thermal stability have shown the phytase to be as efficient as the liquid enzyme extract. Also, the enzyme, while exhibiting optimal activity under acidic conditions, was found to have significant activity in a broad range of pH values (1.5-6.5). The studies suggest the suitability of the koji supplemented with phytase produced in an SSF process by the "generally regarded as safe" (GRAS) microorganism A. niger as a cost-effective value-added livestock feed when compared to that obtained by submerged fermentation (SmF).

  11. Highly efficient production of Aspergillus niger amylase cocktail by solid-state fermentation using triticale grains as a well-balanced substrate

    Directory of Open Access Journals (Sweden)

    Dojnov Biljana

    2015-01-01

    Full Text Available Triticale (Triticosecale, Wittmak an important industrial crop, with high grain yield, containing high amounts of starch, proteins and also major and minor mineral elements, is not sufficiently utilized yet. The simultaneous production of α-amylase and glucoamylase isoforms by Aspergillus niger on triticale grains, without any nutritive supplements, has been developed, optimized and scaled up 10 fold for the first time. The specific combination of examined effects led to the production of a novel glucoamylase isoform. Reduction of particle size, increase of oxygen availability and substrate height lead to increase of amylases production of 30%. Reduction of relative humidity from 65% to 30% increased glucoamylase production 2 times and α-amylase production for 30%. Peak production of α-amylase (158 U/g and glucoamylase (170 U/g were obtained in erlenmayers and in scaled-up trays. The obtained A. niger amylase cocktail was more efficient in raw starch hydrolysis from wheat flour, 29% more efficient in glucose formation and 10% more efficient in total reducing sugar formation, than commercially available amylase cocktail SAN Super 240L widely used in industry. [Projekat Ministarstva nauke Republike Srbije, br. 172048

  12. Production and Characterization of Glucoamylase by Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Soumik Banerjee

    2017-01-01

    Full Text Available Background and Objective: Glucoamylase is a potent starch degrading enzyme whose cheap production has been an area of research. Its production by Aspergillus niger in solid-state fermentation was studied using dried garden pea peel as a substrate, which enormously reduced the production cost. The current study intended to produce glucoamylase by a cost-effective strategy and exhaustively characterize the enzyme.Material and Methods: Garden pea peel was used as a substrate in solid state fermentation by Aspergillus niger for the production of glucoamylase under process parameters. Response surface methodology, a statistical tool for optimization, was applied to setup the experimental design for glucoamylase production. Characterization studies of the enzyme were carried out with temperature, pH, metal salts and elemental composition analysis.Results and Conclusion: The process parameters were temperature, amount of substrate and time of fermentation. Glucoamylase production was highest in the pH range of 5.4-6.2, was stable at pH 3.8, and maintained its maximum activity even at 70°C for 30 min. It showed higher catalytic efficiency when incubated with metal ions Fe2+, Cu2+, Mg2+, and Pb2+. Km and Vmax for glucoamylase were 0.387 mg of soluble starch ml-1 and 35.03 U μl-1 min-1, respectively. Glycogen was also used as a substrate, which gave an increased Km by 2.585, whose KI was found to be 0.631. Energy-dispersive X-ray spectroscopy was performed for obtaining composition of the pea peel. C, N, and O were found to be 12.53%, 29.9%, and 55.27% by atomic weights, respectively. Cost- and time-effective production of glucoamylase was achieved by utilizing dried garden pea peel (a vegetable residue powder as the substrate for production. Its high stability ensures efficient utilization under industrial conditions. This work provides a very good platform for the enzyme immobilization studies and scale up production in future.Conflict of interest

  13. [Family expenses caused by pediatric hospitalization in Niamey (Niger)].

    Science.gov (United States)

    Barennes, H; Azzaratou, I

    1998-01-01

    In Niger, 54.4% of the population live below the poverty level (less than 750 FF per year per person). The government is currently implementing a policy to reduce medical costs, including those of hospitals. We carried out a study during the rainy and dry seasons of 1994-1995, of 80 children, randomly selected, who had been admitted to the pediatric ward of Niamey National Hospital. The total expenditure of their families, due to their hospitalization, was recorded and analyzed. The total expenses of the family were 151.8 (+/- 100.0) to 185.5 (+/- 118.9) FF depending on where the drugs were purchased (wholesale or private). Medical expenses accounted for 98.0 (+/- 48.3) to 119.8 (+/- 57.2) FF, that is 60.0 to 64.5% of total expenses. Non-medical expenses (transport, food, presents) accounted for 61.7 to 65.7 FF, 35.4 to 39.9%. Total daily expenses were 23 to 41.7 FF for the five main diseases. In 66 cases, the costs were paid by the father (82.5%), with the mother or another person paying in 7 cases (8.8%). Only 24 families (30%) paid the hospital fee (10.5 FF). Twenty-seven families were exempted and 22 avoided payment. The cost of medical analysis was 32.6 (+/- 31.3) FF and this was paid by the hospital. The total cost (total family expenditure + hospital expenditure) of a stay in a pediatric unit was 316.5 to 350.4 FF, which is equivalent to 8 to 10 times the mean annual individual expenditure on health in urban areas of Niger. Measures have already been introduced to encourage the prescription of generic drugs and a number of measures are currently under discussion for lowering the cost to families of hospital and health center care and for improving the cost effectiveness of treatment.

  14. Minerals Yearbook, volume I, Metals and Minerals

    Science.gov (United States)

    ,

    2017-01-01

    The U.S. Geological Survey (USGS) Minerals Yearbook discusses the performance of the worldwide minerals and materials industries and provides background information to assist in interpreting that performance. Content of the individual Minerals Yearbook volumes follows:Volume I, Metals and Minerals, contains chapters about virtually all metallic and industrial mineral commodities important to the U.S. economy. Chapters on survey methods, summary statistics for domestic nonfuel minerals, and trends in mining and quarrying in the metals and industrial mineral industries in the United States are also included.Volume II, Area Reports: Domestic, contains a chapter on the mineral industry of each of the 50 States and Puerto Rico and the Administered Islands. This volume also has chapters on survey methods and summary statistics of domestic nonfuel minerals.Volume III, Area Reports: International, is published as four separate reports. These regional reports contain the latest available minerals data on more than 180 foreign countries and discuss the importance of minerals to the economies of these nations and the United States. Each report begins with an overview of the region’s mineral industries during the year. It continues with individual country chapters that examine the mining, refining, processing, and use of minerals in each country of the region and how each country’s mineral industry relates to U.S. industry. Most chapters include production tables and industry structure tables, information about Government policies and programs that affect the country’s mineral industry, and an outlook section.The USGS continually strives to improve the value of its publications to users. Constructive comments and suggestions by readers of the Minerals Yearbook are welcomed.

  15. Shanghai's Fashion During Republic Period

    Institute of Scientific and Technical Information of China (English)

    卞向阳

    2004-01-01

    The goal of this research is to describe and analyze Shanghai's fashion during Republic Period. Shanghai's fashion during Republic Period plays a special role in fashion history of China and Shanghai history. In the paper, three aspects including the fashion centre of China as well as Far East, men's fashion and women's fashion in Shanghai are discussed. The style, textiles, color, decoration and combination of clothing are described. Many costumes from the Clothing Museum at Donghua University and private collections as well as some historical writings, photographs and publications are elucidated and corroborated to give a more detailed description about Shanghai's fashion during that period.Here are some tentative conclusions. Firstly, Shanghai had always been the fashion center in China even Far East during Republic Period. Modeng was the main reflection of Shanghai fashion. Secondly, the traditional clothing exerted less influence and was less widely used, some kinds and combinations were out of fashion gradually. The fashion was described to be highly stylized, exquisite and concise. Thirdly, the influence of Western Style was further greater. The fashion in Shanghai was almost synchronous with fashion of Paris. Some western clothing was directly used in daily life and the elements of Western Style had an increasingly wide utilization. Fourthly, the New Chinese Style whose representatives were Qipao and Zhongshan Zhuang appeared and popularized in Shanghai. The fashion of Qipao changed frequently. Finally, the fashion in Shanghai called Shanghai Style could be summarized fashionable, exquisite, rapidly changeable, which is harmonious of both ancient and modern, Chinese and foreign.

  16. Assessing Niger-Delta Wetland Resources: A Case-Study of Mangrove Ecosystem

    Science.gov (United States)

    Anwan, R. H.; Ndimele, P. E.; Whenu, O. O.; Anetekhai, M. A.; Essien-Ibok, M. A.; Erondu, E. S.

    2016-02-01

    The Niger Delta is located in the Atlantic coast of Southern Nigeria and is the world's second largest delta with a coastline of about 450km. The Niger Delta region occupies a surface area of about 112,110km2, representing about 12% of Nigeria's total surface area. The Delta's environment can be broken down into four ecological zones: coastal barrier islands, mangrove swamp forests, freshwater swamps, and lowland rainforests. The mangrove swamps of Niger Delta, which is the largest delta in Africa constitute the dominant wetland ecosystem in the Niger Delta region and covers an area of about 1,900km2. Mangroves constitute important nurseries for fishes, crustaceans, sponges, algae and other invertebrates, and also acts as a sink, retaining pollutants from contaminated tidal water. The Niger Delta mangrove together with the creeks and rivers are a major source of food and livelihood for about 30 million people, which represents more than 17% of Nigeria's population. Other ecosystem services provided by this unique environment are flood control, ground water re-fill, reservoir of biodiversity, fuel wood, cultural values etc. This ecosystem also plays important role in climate change mitigation because of its high blue carbon sequestration potential. This is particularly important because of continuous gas flaring in Niger Delta from petroleum operations, which releases carbon dioxide among other gases into the atmosphere. This wetland is potentially a good site for ecotourism and also qualifies to be a world heritage site and Ramsar site if proper steps are taken. The benefits derivable from this fragile ecosystem are under severe threat by anthropogenic stressors. These include the installation of pipelines and seismic exploration by oil companies, crude oil pollution, deforestation, urbanization etc. This paper discusses the extent of depletion and loss of mangrove ecosystem in the Niger Delta region and the value of its goods and services.

  17. Miscellaneous Industrial Mineral Operations

    Data.gov (United States)

    Department of Homeland Security — This map layer includes miscellaneous industrial minerals operations in the United States. The data represent commodities covered by the Minerals Information Team...

  18. Toxoplasmosis seroprevalence in urban rodents: a survey in Niamey, Niger

    Science.gov (United States)

    Mercier, Aurélien; Garba, Madougou; Bonnabau, Henri; Kane, Mamadou; Rossi, Jean-Pierre; Dardé, Marie-Laure; Dobigny, Gauthier

    2013-01-01

    A serological survey of Toxoplasma gondii was conducted on 766 domestic and peridomestic rodents from 46 trapping sites throughout the city of Niamey, Niger. A low seroprevalence was found over the whole town with only 1.96% of the rodents found seropositive. However, differences between species were important, ranging from less than 2% in truly commensal Mastomys natalensis, Rattus rattus and Mus musculus, while garden-associated Arvicanthis niloticus displayed 9.1% of seropositive individuals. This is in line with previous studies on tropical rodents - that we reviewed here - which altogether show that Toxoplasma seroprevalence in rodent is highly variable, depending on many factors such as locality and/or species. Moreover, although we were not able to decipher statistically between habitat or species effect, such a contrast between Nile grass rats and the other rodent species points towards a potentially important role of environmental toxoplasmic infection. This would deserve to be further scrutinised since intra-city irrigated cultures are extending in Niamey, thus potentially increasing Toxoplasma circulation in this yet semi-arid region. As far as we are aware of, our study is one of the rare surveys of its kind performed in Sub-Saharan Africa and the first one ever conducted in the Sahel. PMID:23828008

  19. Hyphal differentiation in the exploring mycelium of Aspergillus niger.

    Science.gov (United States)

    Vinck, Arman; Terlou, Maarten; Pestman, Wiebe R; Martens, Edwin P; Ram, Arthur F; van den Hondel, Cees A M J J; Wösten, Han A B

    2005-11-01

    Mycelial fungi play a central role in element cycling in nature by degrading dead organic material such as wood. Fungal colonization of a substrate starts with the invasion of exploring hyphae. These hyphae secrete enzymes that convert the organic material into small molecules that can be taken up by the fungus to serve as nutrients. Using green fluorescent protein (GFP) as a reporter, we show for the first time that exploring hyphae of Aspergillus niger differentiate with respect to enzyme secretion; some strongly express the glucoamylase gene glaA, while others hardly express it at all. When a cytoplasmic GFP was used, 27% of the exploring hyphae of a 5-day-old colony belonged to the low expressing hyphae. By fusing GFP to glucoamylase and by introducing an ER retention signal, this number increased to 50%. This difference is due to cytoplasmic streaming of the reporter in the former case, as was shown by using a photo-activatable GFP. Our findings indicate that a fungal mycelium is highly differentiated, especially when taking into account that hyphae in the exploration zone were exposed to the same nutritional conditions.

  20. Sepal phenolic profile during Helleborus niger flower development.

    Science.gov (United States)

    Schmitzer, Valentina; Mikulic-Petkovsek, Maja; Stampar, Franci

    2013-11-01

    Morphological changes and phenolic patterns of developing hellebore sepals and the effects of pistil removal on these parameters were studied by comparing six flower stages of Helleborus niger. Color changes were evaluated colorimetrically, chlorophyll content was measured spectrophotometrically, and anthocyanins and flavonols were identified and quantified with HPLC-MS. Pistil removal not only altered the morphological development of hellebore flower resulting in smaller flower and significant color changes but also lead to several biochemical modifications. Five cyanidin glycosides have been identified from the group of anthocyanins in hellebore. Individual and total anthocyanin content increased from bud to subsequent developmental stages. Moreover, significantly higher content levels of individual and total anthocyanins have been measured in non-pollinated flower sepals compared to sepals of pollinated flowers. From the group of flavonols eight quercetin and kaempferol compounds have been quantified in hellebore sepals. Flavonol content significantly decreased during flower development with lowest levels recorded in sepals of non-pollinated and senescent pollinated hellebore flowers. Sepals of pollinated flowers contained highest levels of chlorophyll and significantly lower amounts of chlorophyll were measured in non-pollinated flowers and in sepals of senescent stage. Copyright © 2013 Elsevier GmbH. All rights reserved.

  1. ACTION LEVERS FOR A SUSTAINABLE FARMLAND MANAGEMENT IN NIGER

    Directory of Open Access Journals (Sweden)

    Mahamadou Roufahi Tankari

    2015-10-01

    Full Text Available This study aims to contribute to the understanding of factors influencing the sustainable farmland management in Niger. Specifically, it examines the determinants of adoption of sustainable land management practices including measures to combat erosion, and the use of manure, residues and fertilizer with a view to support the formulation of efficient land use policies based on evidences given fact that the impact of factors influencing farmland management appears to be specific to each context. The study is based on data from the National Survey of Household Living Conditions and Agriculture of 2011 (ECVMA-2011 analyzed within the framework of multivariate Probit model. The results show that there are unobservable interdependences between the decisions on farmland management practices. Furthermore, several types of factors related to access to physical, human, financial and biophysical capitals as well as infrastructure and services seem to play an important role. In addition, it appears that more security is needed in land tenure for a sustainable farmland management while farmland defragmentation can act negatively on sustainable farmland management.

  2. Purification, Characterization and Application of Polygalacturonase from Aspergillus niger CSTRF

    Directory of Open Access Journals (Sweden)

    Arotupin Daniel Juwon

    2012-09-01

    Full Text Available Aims: The research was carried out to study the purification, characterization and application of polygalacturonase fromAspergillus niger CSTRF.Methodology and Results: The polygalacturonase (PG from the fungus was purified by ammonium sulphate precipitation and dialysed. The resulting fraction of the enzyme was further separated by molecular exclusion and ion exchange chromatography. The enzyme was purified 28.19 fold with a yield of approximately 69 % following purificationwith SP C-50. It has a relative molecular weight of 79,430 daltons and markedly influenced by temperature, pH and substrate concentrations of reactions with optimum activity at 35 °C, pH 4.0 and 8 mg/mL respectively. The PG was heat stable over a broad range of temperatures. Line weaver-Burk plot for the apparent hydrolysis of pectin showed approximately Km value of 2.7 mg/mL. The activity of the enzyme was enhanced by Na+, Ca2+, Mg2+ and Zn2+, while EDTA, PbCl2, HgCl2 and IAA were inhibitory. The ability of the purified enzyme to clarify fruit juice was also investigated.Conclusion, significance and impact of the study: This study revealed that polygalacturonase possesses properties for clarification of fruit juice and by extension bioprocessing applications.

  3. The transcriptomic fingerprint of glucoamylase over-expression in Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Kwon Min Jin

    2012-12-01

    Full Text Available Abstract Background Filamentous fungi such as Aspergillus niger are well known for their exceptionally high capacity for secretion of proteins, organic acids, and secondary metabolites and they are therefore used in biotechnology as versatile microbial production platforms. However, system-wide insights into their metabolic and secretory capacities are sparse and rational strain improvement approaches are therefore limited. In order to gain a genome-wide view on the transcriptional regulation of the protein secretory pathway of A. niger, we investigated the transcriptome of A. niger when it was forced to overexpression the glaA gene (encoding glucoamylase, GlaA and secrete GlaA to high level. Results An A. niger wild-type strain and a GlaA over-expressing strain, containing multiple copies of the glaA gene, were cultivated under maltose-limited chemostat conditions (specific growth rate 0.1 h-1. Elevated glaA mRNA and extracellular GlaA levels in the over-expressing strain were accompanied by elevated transcript levels from 772 genes and lowered transcript levels from 815 genes when compared to the wild-type strain. Using GO term enrichment analysis, four higher-order categories were identified in the up-regulated gene set: i endoplasmic reticulum (ER membrane translocation, ii protein glycosylation, iii vesicle transport, and iv ion homeostasis. Among these, about 130 genes had predicted functions for the passage of proteins through the ER and those genes included target genes of the HacA transcription factor that mediates the unfolded protein response (UPR, e.g. bipA, clxA, prpA, tigA and pdiA. In order to identify those genes that are important for high-level secretion of proteins by A. niger, we compared the transcriptome of the GlaA overexpression strain of A. niger with six other relevant transcriptomes of A. niger. Overall, 40 genes were found to have either elevated (from 36 genes or lowered (from 4 genes transcript levels under all

  4. Environmental changes in the Central Sahara during the Holocene - The Mid-Holocene transition from freshwater lake into sebkha in the Segedim depression, NE Niger

    Science.gov (United States)

    Baumhauer, Roland; Schulz, Erhard; Pomel, Simon

    The change from a fresh water lake to a sebkha during the middle Holocene was investigated in the Segedim depression/North-eastern Niger using continuous thin sections for micropetrography, palynology and for diatoms. This record is clearly divided into several units showing sequences of laminated anoxic to oxic clays, the stage of a sebkha with an inflow of loess, fine broken quartz grains and salts which are covered by dune sands made of rounded and clay covered quartz. The mineral assemblages of the three principal units are defined by the illite/kaolinitecalcite The diatom assemblages equally show the passage from fresh to saline water. The pollen spectra indicate the change from the Saharan savannah to desert vegetation.

  5. Enantioselective hydrolysis of epichlorohydrin using whole Aspergillus niger ZJB-09173 cells in organic solvents

    Indian Academy of Sciences (India)

    Huo-Xi Jin; Zhong-Ce Hu; Yu-Guo Zheng

    2012-09-01

    The enantioselective hydrolysis of racemic epichlorohydrin for the production of enantiopure ()-epichloro-hydrin using whole cells of Aspergillus niger ZJB-09173 in organic solvents was investigated. Cyclohexane was used as the reaction medium based on the excellent enantioselectivity of epoxide hydrolase from A. niger ZJB-09173 in cyclohexane. However, cyclohexane had a negative effect on the stability of epoxide hydrolase from A. niger ZJB-09173. In the cyclohexane medium, substrate inhibition, rather than product inhibition of catalysis, was observed in the hydrolysis of racemic epichlorohydrin using A. niger ZJB-09173. The racemic epichlorohydrin concentration was markedly increased by continuous feeding of substrate without significant decline of the yield. Ultimately, 18.5% of ()-epichlorohydrin with 98% enantiomeric excess from 153.6 mM of racemic epichlorohydrin was obtained by the dry cells of A. niger ZJB-09173, which was the highest substrate concentration in the production of enantiopure ()-epichlorohydrin by epoxide hydrolases using an organic solvent medium among the known reports.

  6. Evaluation of Antimicrobial Activity of Glucose Oxidase from Aspergillus niger EBL-A and Penicillium notatum

    Directory of Open Access Journals (Sweden)

    Muhammad Anjum Zia

    2013-12-01

    Full Text Available This work aimed to study the production and purification of glucose oxidase by Aspergillus niger and Penicillium notatum using corn steep liquor as the substrate and evaluate its antimicrobial activity for use in pharmaceutical and food industries. The enzyme was purified by ammonium sulfate precipitation (60-85%, DEAE-cellulose ion exchange and Sephadex G-200 size exclusion chromatography. The crude enzyme extracts of A. niger and P. notatum showed 2.32 and 5.53 U mg-1 specific activities, respectively, which after desalting was 15.52 and 12.05 U mg-1, and after ion exchange and gel filtration chromatography was 29.09 - 62 and 25.72 - 59.37 U mg-1 for A. niger and P. notatum, respectively. The antimicrobial activity was determined by disc diffusion method against selected microbial strains where glucose oxidase from A. niger showed anti-bacterial activity, while no fungicidal effects were shown by both A. niger and P. notatum glucose oxidases.

  7. Determinants of pathologic mineralization.

    Science.gov (United States)

    Kirsch, Thorsten

    2008-01-01

    Physiologic mineralization is necessary for the formation of skeletal tissues and for their appropriate functions during adulthood. Mineralization has to be controlled and restricted to specific regions. If the mineralization process occurs in regions that normally do not mineralize, there can be severe consequences (pathologic or ectopic mineralization). Recent findings have indicated that physiologic and pathologic mineralization events are initiated by matrix vesicles, membrane-enclosed particles released from the plasma membranes of mineralization-competent cells. The understanding of how these vesicles are released from the plasma membrane and initiate the mineralization process may provide novel therapeutic strategies to prevent pathologic mineralization. In addition, other regulators (activators and inhibitors) of physiologic mineralization have been identified and characterized, and there is evidence that the same factors also contribute to the regulation of pathologic mineralization. Finally, programmed cell death (apoptosis) may be a contributor to physiologic mineralization and if occurring after tissue injury may induce pathologic mineralization and mineralization-related differentiation events in the injured and surrounding areas. This review describes how the understanding of mechanisms and factors regulating physiologic mineralization can be used to develop new therapeutic strategies to prevent pathologic or ectopic mineralization events.

  8. A new group of exo-acting family 28 glycoside hydrolases of Aspergillus niger that are involved in pectin degradation

    NARCIS (Netherlands)

    Martens-Uzunova, E.S.; Zandleven, J.S.; Benen, J.A.E.; Awad, H.; Kools, H.J.; Beldman, G.; Voragen, A.G.J.; Berg, van den J.A.; Schaap, P.J.

    2006-01-01

    The fungus Aspergillus niger is an industrial producer of pectin degrading enzymes. The recent solving of the genomic sequence of A. niger allowed an inventory of the entire genome of the fungus for potential carbohydrate degrading enzymes. By applying bioinformatics tools 12 new genes putatively

  9. Design and production in Aspergillus niger of a chimeric protein associating a fungal feruloyl esterase and a clostridial dockerin domain

    NARCIS (Netherlands)

    Levasseur, A.; Pagès, S.; Fierobe, H.-P.; Navarro, D.; Punt, P.; Belaïch, J.-P.; Asther, M.; Record, E.

    2004-01-01

    A chimeric enzyme associating feruloyl esterase A (FAEA) from Aspergilhis niger and dockerin from Clostridium thermocellum was produced in A. niger. A completely truncated form was produced when the dockerin domain was located downstream of the FAEA (FAEA-Doc), whereas no chimeric protein was produc

  10. Basic Education Awareness Campaign Conducted in Niger with Trade Unions, Parents' Representatives and Political Authorities at Various Levels

    Science.gov (United States)

    Oumarou, Hamissou; Namata, Issa

    2006-01-01

    Education policy in Niger is made up of all the tendencies and decisions, which over time have determined the development of Niger's education sector and its components. In this article, the author discusses the implementation stages of education policy, that is: (1) Adoption of the General Policy Act; and (2) Planning of the implementation of the…

  11. Host-Pathogen Interactions: VI. A Single Plant Protein Efficiently Inhibits Endopolygalacturonases Secreted by Colletotrichum Lindemuthianum and Aspergillus Niger.

    Science.gov (United States)

    Fisher, M L; Anderson, A J; Albersheim, P

    1973-03-01

    Endopolygalacturonases have been purified from the extracellular enzymes of Colletotrichum lindemuthianum and Aspergillus niger. A protein, purified from Red Kidney (Phaseolus vulgaris) beans for its ability to inhibit the endopolygalacturonase secreted by C. lindemuthianum, inhibits the A. niger endopolygalacturonase almost as efficiently as it inhibits the C. lindemuthianum enzyme.

  12. Variability in growth of Vachellia nilotica provenances tested in the Sudano-Sahelian zone of Niger

    DEFF Research Database (Denmark)

    Larwanou, Mahamane; Issa, Rabiou; Saadou, Mahamane;

    2014-01-01

    A provenance trial of Vachellia nilotica (Acacia nilotica) was conducted in Niger in order to assess variability in growth among 10 provenances from Africa (subsp. adstringens from Niger, Senegal and Cameroun) and outside the continent (subsp. indica from Pakistan and Yemen). Tree height, diamete...

  13. A preliminary sketch of the georesources in Niamey city (Niger)

    Science.gov (United States)

    Spadafora, Francesco; De Luca, Domenico A.; Antonella Dino, Giovanna; Lasagna, Manuela; Perotti, Luigi; Yadji, Guero; Tankari Dan-Badjo, Abdourahamane; Moussa, Issaka; Harouna, Moussa; Moussa, Konaté

    2015-04-01

    The present paper is about a preliminary study of the georesources (water and raw materials for construction) of Niamey city (Niger). Such research is part of an UNICOO project (funded by the University of Turin) and connected to the Edulink Cooperation Project (R.U.S.S.A.D.E.), a multidisciplinary project between Italy, Niger, Burquina Faso and Tchad funded on ACP- EU cooperation program in Higher Education. The main goals are the qualitative and quantitative characterization of the surface water and groundwater, and of aggregates (exploited in sands and gravel quarries). More specifically, at the beginning of the study there was a census of wells and quarries in the Niamey area, with a consequent sampling survey (surface water and groundwater sampling and aggregate sampling). After that, an in situ characterization was set: measure of piezometric levels in wells, water characterization (pH, electrolytic conductivity, temperature, nitrate and ammonia concentration) and an in situ evaluation of the quarrying techniques and quarry exploitation (present and old quarries). The samples were analyzed in Earth Science Dep. (UNITO) to evaluate the content of the main anions and cations (chemical analysis of sampled water) and the size distribution of the materials coming from the investigated quarries. Schematic reports of wells and quarries (location and features) were produced with the support of a Geodatabase with all available data. Geomatics instruments and methodologies (Geotagged Photos, Digital Mapping, GNSS Survey, Satellite Multitemporal Maps,) were basic starting point for the field data collection and a fundamental aid for data arrangement and final dissemination. The present study evidenced the actual condition of surface water and groundwater, also highlighting local phenomena of pollution. Nitrate in groundwater, i.e., showed locally concentration up to 5 times the WHO limit (50 mg/L). Thanks to the local quarry survey it was possible to evaluate how the

  14. Novel Antifungal Peptides Produced by Leuconostoc mesenteroides DU15 Effectively Inhibit Growth of Aspergillus niger.

    Science.gov (United States)

    Muhialdin, Belal J; Hassan, Zaiton; Abu Bakar, Fatimah; Algboory, Hussein L; Saari, Nazamid

    2015-05-01

    The ability of Leuconostoc mesenteroides DU15 to produce antifungal peptides that inhibit growth of Aspergillus niger was evaluated under optimum growth conditions of 30 °C for 48 h. The cell-free supernatant showed inhibitory activity against A. niger. Five novel peptides were isolated with the sequences GPFPL, YVPLF, LLHGVPLP, GPFPLEMTLGPT, and TVYPFPGPL as identified by de novo sequencing using PEAKS 6 software. Peptide LLHGVPLP was the only positively charged (cationic peptides) and peptide GPFPLEMTLGPT negatively charged (anionic), whereas the rest are neutral. The identified peptides had high hydrophobicity ratio and low molecular weights with amino acids sequences ranging from 5 to 12 residues. The mode of action of these peptides is observed under the scanning electron microscope and is due to cell lysis of fungi. This work reveals the potential of peptides from L. mesenteroides DU15 as natural antifungal preservatives in inhibiting the growth of A. niger that is implicated to the spoilage during storage.

  15. Characterization of novel thermostable polygalacturonases from Penicillium brasilianum and Aspergillus niger.

    Science.gov (United States)

    Zeni, Jamile; Pili, Jonaina; Cence, Karine; Toniazzo, Geciane; Treichel, Helen; Valduga, Eunice

    2015-12-01

    The aim of this research was the partial characterization of polygalacturonase (PG) extracts produced by a newly isolated Penicillium brasilianum and Aspergillus niger in submerged fermentation. The partial characterization of the crude enzymatic extracts showed optimum activity at pH 5.5 and 37 °C for both extracts. The results of temperature stability showed that PG from both microorganisms were more stable at 55 °C. However, the enzyme obtained by P. brasilianum presents a half-life time (t 1/2 = 693.10 h), about one order of magnitude higher than those observed in for A. niger at 55 °C. In terms of pH stability, the PG produced by P. brasilianum presented higher stability at pH 4.0 and 5.0, while the PG from A. niger showed higher stability at pH 5.0.

  16. Sand Failure Mechanism and Sanding Parameters in Niger Delta Oil Reservoirs

    Directory of Open Access Journals (Sweden)

    Sunday Isehunwa,

    2010-05-01

    Full Text Available Sand production is a major issue during oil and gas production from unconsolidated reservoirs. In predicting the onset of sand production, it is important to accurately determine the failure mechanism and the contributing parameters. The aim of this study was to determine sand failure mechanism in the Niger-Delta, identify themajor contributing parameters and evaluate their effects on sanding.Completion and production data from 78 strings completed on 22 reservoirs in a Niger Delta oil Field were evaluated. Sand failure mechanisms and contributing parameters were identified and compared with published profiles. The results showed that cohesive stress is the predominant sand failure mechanism. Water cut, bean size and gas oil ratio (GOR impact sand production in the Niger Delta.

  17. Heterologous expression of the Aspergillus nidulans alcR-alcA system in Aspergillus niger.

    Science.gov (United States)

    Nikolaev, I; Mathieu, M; van de Vondervoort, P; Visser, J; Felenbok, B

    2002-10-01

    The inducible and strongly expressed alcA gene encoding alcohol dehydrogenase I from Aspergillus nidulans was transferred together with the activator gene alcR, in the industrial fungus Aspergillus niger. This latter organism does not possess an inducible alc system but has an endogenously constitutive lowly expressed alcohol dehydrogenase activity. The overall induced expression of the alcA gene was of the same order in both fungi, as monitored by alcA transcription, alcohol dehydrogenase activity and heterologous expression of the reporter enzyme, beta-glucuronidase. However, important differences in the pattern of alcA regulation were observed between the two fungi. A high basal level of alcA transcription was observed in A. niger resulting in a lower ratio of alcA inducibility. This may be due to higher levels of the physiological inducer of the alc regulon, acetaldehyde, from general metabolism in A. niger which differs from that of A. nidulans.

  18. Cadmium regulation by Lasius niger:A contribution to understanding high metal levels in ants

    Institute of Scientific and Technical Information of China (English)

    Irena M.Grze(s)

    2009-01-01

    Ants(Formicinae.Hymenoptera)are considered efficient accumulators of Zn and Cd.In this study the relationship between Cd concentrations in soil and in Lasius niger workers was assessed for 20 colonies located along a gradient of Cd pollution.As soil Cd concentration increased from 1 to 8 mg/kg.ant body Cd concentration increased rapidly to about 40mg/kg,andremained stable atthislevel,through a progressive increase of soil Cd concentration from 8 to 21 mg/kg.The phase of rapid increase confirms the high ability of L niger for Cd accumulation.while the stabilization of Cd body concentration indicates either increasing elimination rate or decreasing rate of uptake.Therefore it Can be concluded that Lasius niger has a high ability to accumulate Cd,but simultaneously an ability for Cd regulation was detected.

  19. DNA-based identification of Helleborus niger by high-resolution melting analysis.

    Science.gov (United States)

    Schmiderer, Corinna; Mader, Eduard; Novak, Johannes

    2010-11-01

    Hellbori nigri rhizoma is a drug that is difficult to distinguish from other species of the genus Helleborus. In this communication we present a DNA-based identification by high-resolution melting analysis (HRM) that is able to differentiate between Helleborus niger and other species of the genus. HRM is a very specific, time- and labour-saving method for identifying DNA sequence variations and is ideally suitable for routine PCR analysis. The HRM assay developed is specific for the genus Helleborus. This method not only detects the presence of the target species H. niger but also, to a certain extent, identifies other Helleborus species by their different melting curve shapes. Markers were developed based on the trnL-trnF intergenic spacer and on the matK sequence. For an unambiguous identification of Helleborus niger, melting curves of both markers should be used. © Georg Thieme Verlag KG Stuttgart · New York.

  20. The Dynamics of Oil and Social Movements in the Niger Delta of Nigeria

    Directory of Open Access Journals (Sweden)

    Victor Ojakorotu

    2006-02-01

    Full Text Available The discovery of oil in Nigeria since 1956 has inflicted a heavy burden on the local people of the Niger River Delta who have had to contend with the consequences of oil production. The grievances of these local people have persisted for more than three decades without concrete efforts on the part of the government or oil multinationals to address them. The global triumph of capitalism and the fall of communism gave the local people an opportunity to organize social movements with similar interests to international civil society to challenge the policies of successive governments and the activities of oil multinationals in the Niger Delta. This paper addresses the factors that led to a sudden upsurge in the number of social movements in the Niger Delta and how foreign NGOs have played an important role in addressing the plight of the local people of the region.

  1. Overweight and obesity profiles in Niger Delta Region, Nigeria

    Directory of Open Access Journals (Sweden)

    Alphhonsus U. Idung

    2014-01-01

    Full Text Available Introduction: Overweight and obesity are global public health problems because of their effect on individuals, families and communities. The objective of this study was to describe the profile of overweight and obesity amongst adult out patients in Uyo in the Niger Delta region of Nigeria.Method: This was a cross-sectional descriptive study done between October 2011 and March 2012. Using a systematic sampling technique, 584 subjects aged 18–65 years were recruited; data were collected with a structured questionnaire. Subjects were measured for height, weight, waist and hip circumferences. Body mass index (BMI and waist–hip ratio (WHR were calculated. Subjects with a BMI of 25.0 kg/m2 – 29.9 kg/m2 were regarded as being overweight whilst a BMI of > 30.0 kg/m2 was regarded as obese. Subjects with a WHR of > 0.90 for men or > 0.85 for women were regarded as having abnormal WHR.Results: Of the 584 subjects, 196 (36.6% were men and 388 (66.4% women. The mean age for men and women was 43.3 ± 17.8 years and 50.2 ± 13.6 years, respectively. The prevalence of overweight amongst men was 39.8% versus 31.7% for women; obesity in men was 28.0% versus 52.0% in women. Overweight and obesity were more prevalent in subjects aged 25–54 years and amongst married subjects. There was a significant relationship between obesity and television viewing (p = 0.003. Hypertension (p = 0.008 and osteoarthropathies (p = 0.043 were more prevalent amongst the obese than the non-obese subjects.Conclusion: Overweight and obesity are now common in our environment. There is therefore a need for more public education about the health consequences of big body size.

  2. Laparoscopic cholecystectomy in sickle cell patients in Niger

    Directory of Open Access Journals (Sweden)

    Abarchi Habibou

    2009-12-01

    Full Text Available BACKGROUND: We report the results of our experience on laparoscopic cholecystectomy in sickle cell disease patients in Niger, which is included in the sickle cell belt. METHODS: A prospective study covering a period of 45 months, from July 2004 to March 2008. We included all sickle cell disease patients that underwent laparoscopic cholecystectomy. Blood transfusion was done for patients with haemoglobin (Hb levels less than 9g/dl. Homozygous and composite heterozygous patients were admitted in intensive care unit for 24 hours or plus post operatively. RESULTS:The series included 47 patients operated by the same surgeon, 31 females (66% and 16 males (34% (Ratio: 0.51. The average age was 22.4 years (range: 11 to 46 years and eleven (23.4% of them were aged less than 15 years. The types of sickle cell disease found were 37 SS, 2 SC, 1 S beta-thalassemia and 7 AS. Indications for surgery were biliary colic in 29 cases (61.7% and acute cholecystitis in 18 cases (38.3%. The mean operative time was 64 min (range: 42 to 103 min. Conversion to open cholecystectomy in 2 cases (4.2 % for non recognition of Calot‘s triangle structures. The postoperative complications were: four (4 cases of vaso-occlusive crisis and one case of acute chest syndrome. The mean postoperative hospital stay was 3,5days (range: 1 to 9 days. No mortality was encountered. CONCLUSION: Laparoscopic cholecystectomy is a safe procedure in sickle cell patients. It should be a multidisciplinary approach and involve a haematologist, an anaesthesiologist and a surgeon.

  3. Effect of temperature and water activity on the production of fumonisins by Aspergillus niger and different Fusarium species

    DEFF Research Database (Denmark)

    Mogensen, Jesper Mølgaard; Nielsen, Kristian Fog; Samson, Robert A.

    2009-01-01

    Background Fumonisins are economically important mycotoxins which until recently were considered to originate from only a few Fusarium species. However recently a putative fumonisin gene cluster was discovered in two different Aspergillus niger strains followed by detection of an actual fumonisin B......2 (FB2) production in four strains of this biotechnologically important workhorse. Results In the present study, a screening of 5 A. niger strains and 25 assumed fumonisin producing Fusarium strains from 6 species, showed that all 5 A. niger strains produced FB2 and 23 of 25 Fusarium produced...... fumonisin B1 and other isoforms (fumonisin B2 and B3). Five A. niger and five Fusarium spp. were incubated at six different temperatures from 15-42°C on Czapek Yeast Agar +5% salt or Potato Dextrose Agar. A. niger had the highest production of FB2 at 25-30°C whereas Fusarium spp. had the maximal production...

  4. Hydrological and geochemical studies on the Sahelo-Sudanian basin of the Niger River; Hydrologie et geochimie du bassin soudano-sahelien du fleuve Niger

    Energy Technology Data Exchange (ETDEWEB)

    Olivry, J.C. [ORSTOM, 34 - Montpellier (France)

    1998-12-31

    African drought and rainfall deficits observed during the last twenty years had important repercussions on the runoff of the Niger River (annual deficit of 20 % during the 70`s and of 46 % during the 80`s). A large reduction of the groundwater storage explains the persistent degradation of the hydrological resource. The inner Delta of the Niger River is a particular system submitted to Sahelian and sub-desertic climatic conditions, and is characterized by large flood plains. Time series of input water volumes in the inner Delta and of the water losses inside it show that the water losses, due to the intense evaporation, vary from 40 km{sup 3} to 6 km{sup 3}. The water losses are maximum during the wettest years, up to 47 %, and minimum during the driest years, only 32 %, due to the reduction of the flooded area. Since 1990 the EQUANIS program associates hydrological and chemical measurements in the study of the dissolved and suspended matter flows in the Niger River`s flows to the Sahel. The specific sediment load vary between 7 or 8 t dm{sup 2} year{sup -1} for the upper Niger River and 3 t km{sup 2} year{sup -1} for the Bani River. The specific dissolved load vary between 10 or 12 t km{sup 2} year{sup -1} for the Niger River and 2,5 t km{sup 2} year{sup -1} for the Bani River. The annual input in the inner Delta was about 2,2 Mt in 1992-1993. Seasonal variations of the matter fluxes are very different between the upper and the lower parts of the inner Delta, due to the breaking of the annual flood and to the more important flood plains in the upper Delta. The preliminary results indicate that both rivers have a low level in dissolved element concentration. The inner Delta is not an old sedimentary basin and the actual deposits of matter should characterize its working during the lasting deficit of the water resources of the Niger River. (author) 11 refs.

  5. Oil Multinational Corporations, Environmental Irresponsibility and Turbulent Peace in the Niger Delta Multinationale Ölgesellschaften, ökologische Verantwortungslosigkeit und instabiler Frieden im Niger-Delta

    Directory of Open Access Journals (Sweden)

    Daniel E. Agbiboa

    2013-01-01

    Full Text Available For many oil-bearing communities in petro-states around the world, the net effects of oil exploration have not only been devastating, but have also highlighted the double standards that are often applied by oil multinational corporations (MNCs. These organisations are far more likely to demand environmental and social mitigation efforts in the developed world than they are in a developing country. This paper seeks to demonstrate how the continued irresponsible activities of oil MNCs – specifically Shell – have fuelled restive conditions of ethnic militancy, brazen human rights abuses, environmental degradation and unsustainable peace in the Niger Delta. The paper particularly assesses the impact of the 2009 amnesty programme that was initiated to halt the downward spiral into violence in the Niger Delta and resolve the region’s socio-economic challenges. The conclusion of this paper canvasses for greater social-ecological justice as a way forwards in addressing the Niger Delta conflict.Die Erdölexploration hatte weltweit nicht nur verheerende Auswirkungen in den Ölförderregionen, sondern es wurde auch deutlich, dass Multinationale Unternehmen (MNU im Ölsektor vielfach mit zweierlei Maß messen: Sie sind viel eher geneigt, in den Industrieländern Anstrengungen zur Milderung von Umwelt- und sozialen Schäden einzufordern als in Entwicklungsländern. Dieser Beitrag versucht aufzuzeigen, auf welche Weise die nach wie vor verantwortungslosen Praktiken von Öl-MNU – insbesondere von Shell – zum Aufbrechen latenter ethnischer Spannungen und zu schamlosen Menschenrechtsverletzungen, zur Umweltzerstörung und zur Gefährdung des Friedens im Niger-Delta beitragen. Die Autoren untersuchen insbesondere die Wirkungen des Amnestieprogramms von 2009, das initiiert worden war, um die Gewaltspirale im Niger-Delta zu durchbrechen und die sozioökonomischen Probleme der Region zu lösen. Im Ergebnis plädieren sie für größere soziale und

  6. MAIN PROBLEMS AND PROSPECTS OF REPUBLIC OF BELARUS IN RESPECT OF ITS ENTRY TO INTERNATIONAL BOTTLED WATER MARKET

    Directory of Open Access Journals (Sweden)

    P. G. Nikitenko

    2009-01-01

    Full Text Available The Republic of Belarus has significant reserves of ground fresh and mineral water. Consumption of bottled water in the world has a tendency of steady growth. In this regard, Belarus can increase production and sale of bottled water on the external  and domestic markets as well. The paper  describes main tendencies prevailing on the world market;  it contains an analysis of the normative and legal foundation on regulation of production and sale of bottled water in the Republic and abroad; the paper also estimates the possibilities to increase volume of export water. 

  7. Yarlongite:A New Metallic Carbide Mineral

    Institute of Scientific and Technical Information of China (English)

    SHI Nicheng; BAI Wenji; LI Guowu; XIONG Ming; FANG Qingsong; YANG Jingsui; MA Zhesheng; RONG He

    2009-01-01

    Yarlongite occurs in ophiolitic chromitite at the Luobusha mine(29°5'N 92°,5'E,about 200 km ESE of Lhasa),Qusum County,Shannan Prefecture,Tibet Autonomous Region,People'S Republic of China.Associated minerals are:diamond,moissanite,wiistite,iridium("osmiridium"), osmium("iridosmine"),periclase,chromite,native irun,native nickel,native chromium,forsterite. Cr-rich diopside,intermetallic compounds Ni-Fe-Cr,Ni-Cr,Cr-C,etc.Yariongite and its associated minerals were handpicked from a large heavy mineral sample of chromitite.The metallic carbides associated with yarlongite are cohenite,tongbaite,khamrabaevite and qusongite(IMA2007.034). Yarlongite occurs as irregular grains,with a size between 0.02 and 0.06 mm,steel-grey colour,H Mohs:5 1/2-6.Tenacity:brittle.Cleavage:{0 0 1}perfect.Fracture:conchoidal.Chemical formula: (Cr4Fe4Ni)∑9C4,or(Cr,Fe,Ni)∑9C4,Crystal system:Hexagonal,Space Group:P63/mc,a=18.839(2)A,C =4.4960(9)A,V=745.7(2)A3,Z=6,Density(calc.)=7.19 g/cm3(with simplified formula).Yarlongite has been approved as a new mineral by the CNMNC(IMA2007-035).Holotype material is deposited at the Geological Museum of China(No.M11650).

  8. Generation, annotation, and analysis of an extensive Aspergillus niger EST collection

    Directory of Open Access Journals (Sweden)

    Min Xiang

    2006-02-01

    Full Text Available Abstract Background Aspergillus niger, a saprophyte commonly found on decaying vegetation, is widely used and studied for industrial purposes. Despite its place as one of the most important organisms for commercial applications, the lack of available information about its genetic makeup limits research with this filamentous fungus. Results We present here the analysis of 12,820 expressed sequence tags (ESTs generated from A. niger cultured under seven different growth conditions. These ESTs identify about 5,108 genes of which 44.5% code for proteins sharing similarity (E ≤ 1e -5 with GenBank entries of known function, 38% code for proteins that only share similarity with GenBank entries of unknown function and 17.5% encode proteins that do not have a GenBank homolog. Using the Gene Ontology hierarchy, we present a first classification of the A. niger proteins encoded by these genes and compare its protein repertoire with other well-studied fungal species. We have established a searchable web-based database that includes the EST and derived contig sequences and their annotation. Details about this project and access to the annotated A. niger database are available. Conclusion This EST collection and its annotation provide a significant resource for fundamental and applied research with A. niger. The gene set identified in this manuscript will be highly useful in the annotation of the genome sequence of A. niger, the genes described in the manuscript, especially those encoding hydrolytic enzymes will provide a valuable source for researchers interested in enzyme properties and applications.

  9. Germination of Aspergillus niger conidia is triggered by nitrogen compounds related to L-amino acids.

    Science.gov (United States)

    Hayer, Kimran; Stratford, Malcolm; Archer, David B

    2014-10-01

    Conidial germination is fundamentally important to the growth and dissemination of most fungi. It has been previously shown (K. Hayer, M. Stratford, and D. B. Archer, Appl. Environ. Microbiol. 79:6924-6931, 2013, http://dx.doi.org/10.1128/AEM.02061-13), using sugar analogs, that germination is a 2-stage process involving triggering of germination and then nutrient uptake for hyphal outgrowth. In the present study, we tested this 2-stage germination process using a series of nitrogen-containing compounds for the ability to trigger the breaking of dormancy of Aspergillus niger conidia and then to support the formation of hyphae by acting as nitrogen sources. Triggering and germination were also compared between A. niger and Aspergillus nidulans using 2-deoxy-D-glucose (trigger), D-galactose (nontrigger in A. niger but trigger in A. nidulans), and an N source (required in A. niger but not in A. nidulans). Although most of the nitrogen compounds studied served as nitrogen sources for growth, only some nitrogen compounds could trigger germination of A. niger conidia, and all were related to L-amino acids. Using L-amino acid analogs without either the amine or the carboxylic acid group revealed that both the amine and carboxylic acid groups were essential for an L-amino acid to serve as a trigger molecule. Generally, conidia were able to sense and recognize nitrogen compounds that fitted into a specific size range. There was no evidence of uptake of either triggering or nontriggering compounds over the first 90 min of A. niger conidial germination, suggesting that the germination trigger sensors are not located within the spore.

  10. Removal of silver nanoparticles using live and heat shock Aspergillus niger cultures.

    Science.gov (United States)

    Gomaa, Ola M

    2014-06-01

    Silver nanoparticles (SNPs) are extensively used in many industrial and medical applications; however, the impact of their release in the environment is still considered an understudied field. In the present work, SNPs present in aqueous lab waste water (average size of 30 nm) were used to determine their impact on microflora if released in soil rhizosphere and sewage waste water. The results showed that 24 h incubation with different SNP concentrations resulted in a 2.6-fold decrease for soil rhizosphere microflora and 7.45-fold decrease for sewage waste water microflora, both at 24 ppm. Live and heat shock (50 and 70 °C) Aspergillus niger cultures were used to remove SNP waste, the results show 76.6, 81.74 and 90.8 % SNP removal, respectively after 3 h incubation. There was an increase in the log total bacterial count again after SNP removal by A. niger in the following order: live A. niger niger niger. The pH value decreased from 5.8 to 3.8 in the same order suggesting the production of an acid in the culture media. Scanning electron microscopy images showed agglomeration and/or complexation of SNP particles, in a micron size, in between the fungal mycelia, hence settling on and in between the mycelial network. The results suggest that silver was reduced again and agglomerated and/or chelated together in its oxidized form by an acid in A. niger media. More studies are recommended to determine the acid and the heat shock proteins to confirm the exact mode of action.

  11. The oil rich Niger Delta region: a framework for improved performance of the Nigerian regulatory process.

    Science.gov (United States)

    Onu, N Chukemeka Hemanachi

    2003-06-01

    The adoption of this policy framework has the ability to reconcile industry, the environment and community interests, taking into account all factors that are relevant to managing developments that are both sustainable and contributory to the achievement of industrial and community stability. The management of resource development is crucial in sustaining the Niger Delta ecosystem and the human population resident in the Niger Delta region. If these separate bodies are constituted they would have the potential to reduce and discourage: i) the vulnerability of the regulatory body to influential and powerful multinational oil companies; ii) the proclivity for unaccountability to the people of the Niger Delta region, since the people of the Niger Delta would have access to the regulatory body's classified and unclassified information, and are part of the decision-making process; and iii) a reduction in conflict between the oil mining companies and the aggrieved youths of the oil rich Niger Delta region. This policy framework also has the added advantage of producing high quality decisions and more acceptable decisions than those for which the people of the Niger Delta region are excluded from the processes that concern their existence. The agency decision-making could now become a multilateral process and thus promote and enhance the accurate, impartial and rational application of legislative directives to given cases or classes of cases. Most importantly, the Minister of Petroleum Resources should be empowered by legislation to revoke any license or lease in respect of an area designated as marginal if left undeveloped for a period of 5 years and grant a lease or license for the area to a more responsible oil company.

  12. ASPERGILLUS NIGER ASPERGILLUS NIGER

    African Journals Online (AJOL)

    User

    1, 2, 3DEPARTMENT OF CHEMICAL E. E-mail addresses: ddresses: ... e production of citric acid was a growth associated process. Optimum pH ... l design and operational parameters uently leads to the ..... an isothermal CSTR for methanol synthesis. Journal ... analysis and constrained optimization of citric acid production ...

  13. Systemic analysis of the response of Aspergillus niger to ambient pH

    DEFF Research Database (Denmark)

    Andersen, Mikael Rørdam; Lehmann, Linda Olkjær; Nielsen, Jens

    2009-01-01

    Background: The filamentous fungus Aspergillus niger is an exceptionally efficient producer of organic acids, which is one of the reasons for its relevance to industrial processes and commercial importance. While it is known that the mechanisms regulating this production are tied to the levels...... efficient acidification as well as production process applicable knowledge on the transcriptional regulation of pH response in the industrially important A. niger. It has also made clear that filamentous fungi have evolved to employ several offensive strategies for out-competing rival organisms....

  14. The infrared spectral transmittance of Aspergillus niger spore aggregated particle swarm

    Science.gov (United States)

    Zhao, Xinying; Hu, Yihua; Gu, Youlin; Li, Le

    2015-10-01

    Microorganism aggregated particle swarm, which is quite an important composition of complex media environment, can be developed as a new kind of infrared functional materials. Current researches mainly focus on the optical properties of single microorganism particle. As for the swarm, especially the microorganism aggregated particle swarm, a more accurate simulation model should be proposed to calculate its extinction effect. At the same time, certain parameters deserve to be discussed, which helps to better develop the microorganism aggregated particle swarm as a new kind of infrared functional materials. In this paper, take Aspergillus Niger spore as an example. On the one hand, a new calculation model is established. Firstly, the cluster-cluster aggregation (CCA) model is used to simulate the structure of Aspergillus Niger spore aggregated particle. Secondly, the single scattering extinction parameters for Aspergillus Niger spore aggregated particle are calculated by using the discrete dipole approximation (DDA) method. Thirdly, the transmittance of Aspergillus Niger spore aggregated particle swarm is simulated by using Monte Carlo method. On the other hand, based on the model proposed above, what influences can wavelength causes has been studied, including the spectral distribution of scattering intensity of Aspergillus Niger spore aggregated particle and the infrared spectral transmittance of the aggregated particle swarm within the range of 8~14μm incident infrared wavelengths. Numerical results indicate that the scattering intensity of Aspergillus Niger spore aggregated particle reduces with the increase of incident wavelengths at each scattering angle. Scattering energy mainly concentrates on the scattering angle between 0~40°, forward scattering has an obvious effect. In addition, the infrared transmittance of Aspergillus Niger spore aggregated particle swarm goes up with the increase of incident wavelengths. However, some turning points of the trend

  15. Formation of Sclerotia and Production of Indoloterpenes by Aspergillus niger and Other Species in Section Nigri

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Petersen, Lene Maj; Lyhne, Ellen Kirstine

    2014-01-01

    Several species in Aspergillus section Nigri have been reported to produce sclerotia on well-known growth media, such as Czapek yeast autolysate (CYA) agar, with sclerotia considered to be an important prerequisite for sexual development. However Aspergillus niger sensu stricto has not been...... reported to produce sclerotia, and is thought to be a purely asexual organism. Here we report, for the first time, the production of sclerotia by certain strains of Aspergillus niger when grown on CYA agar with raisins, or on other fruits or on rice. Up to 11 apolar indoloterpenes of the aflavinine type...

  16. Elucidation of the biosynthesis of meroterpenoid yanuthone D in Aspergillus Niger

    DEFF Research Database (Denmark)

    Holm, Dorte Koefoed; Petersen, Lene Maj; Klitgaard, Andreas

    2012-01-01

    We have elucidated the mode of biosynthesis of the meroterpenoid compound Yanuthone D in Aspergillus niger. We have successfully deleted all cluster genes, and identified a number of intermediates. Structures of the intermediates were solved using a combined approach comprising classical 1D- and 2D......-NMR and tandem mass spectrometry (MS/MS). In this study we have confirmed that Yanuthone D is of meroterpenoid origin, and we have identified an unexpected precursor, which has not before been reported for Aspergillus niger....

  17. Expression of soluble human tumor necrosis factor receptor Ⅰ in Aspergillus niger

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The cDNA of soluble human tumor necrosis factor receptorⅠ(sTNFRI) was inserted into fusion-protein expression plasmid pIGF of A. niger to construct fusion expression vector pHBC containing a KEX2 like protein processing site designed on the fusion position. Extracellular protease-deficient strain of A. niger 3.795-1-23 was transformed with pHBC. Positive clone was estimated by Southern hybridization. SDS-PAGE for protein produced by re-combinant strain showed the distinctive expression band. Western blotting indicated that the secreted protein had immunoactivity of sTNFRI.

  18. Victims, villains or heroes? : the local community perception of oil bunkering in the Niger delta

    OpenAIRE

    2015-01-01

    Grounded on a political ecology approach, this study sheds light on oil bunkering activity that is done by local militants in the Niger Delta region of Nigeria. Such oil bunkering is used as a euphemism for oil theft in Nigeria. The purpose of this thesis is to investigate the perception of oil bunkering that is done by groups (militants) of the local communities of the Niger Delta. By collecting and comparing the narratives of the three actors linked to so-called illegal oil b...

  19. Intra and extracellular nuclease production by Aspergillus niger and Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Ferreira Adlane V. B.

    1998-01-01

    Full Text Available Intra and extracellular nuclease production by strains of Aspergillus niger and Aspergillus nidulans was estimated using a modified DNAse test agar and cell-free extract assays. Differences in the production of nucleases by A. niger and A. nidulans were observed. These observations suggest that the DNAse test agar can be helpful for a quick screening for some types of nucleases in filamentous fungi. The assays using cell-free extracts can also be useful for initial characterization of other types of nucleases.

  20. Measles vaccine effectiveness in standard and early immunization strategies, Niger, 1995.

    OpenAIRE

    Kaninda, A V; Legros, D; Jataou, I M; Malfait, P.; Maisonneuve, M; Paquet, C; Moren, A.

    1998-01-01

    BACKGROUND: An Expanded Programme on Immunization was started in late 1987 in Niger, including vaccination against measles with one dose of standard titer Schwarz vaccine given to infants after 9 months of age. During epidemics an early two-dose strategy was implemented (one dose between 6 and 8 months and one dose after 9 months). From January 1, 1995, until May 7, 1995, 13 892 measles cases were reported in Niamey, Niger. METHODS: A retrospective cohort study was conducted in a crowded area...

  1. Kosovo - An Atypical Parliamentary Republic

    Directory of Open Access Journals (Sweden)

    Murat Jashari

    2016-07-01

    Full Text Available The topic of this comparative study is the republican character of the system of governance in Kosovo. In the public discourse and political communication, as well as in academic discourse Kosovo is considered a Parliamentary Republic, based on the principle “of the separation of powers and checks and balances between them.” Although the constitutional definition of the relationship between the executive and legislative favors parliamentary republicanism, the constitutional powers of the president, the government and especially the constitutional and political power of the prime minister, significantly weaken the parliamentary character, in favor of a semi-presidential system. However, neither the current theories of government, nor constitutional provisions can rank Kosovo among semi-presidential systems, or pure parliamentary systems. Comparisons of competence powers relations in Kosovo, with similar relations and competences of the countries of the region and beyond, testify to the specific nature of parliamentary democracy in Kosovo. It is precisely the comparison of the Kosovo constitutional-legal system of governance with similar systems and theoretical analysis of parliamentary models facing Kosovo model which will be the basis of support of the hypothesis that Kosovo is not a typical parliamentary republic.

  2. Analcite formation in the Agades Region (Niger); Les formations a analcime de la Region d'Agades (Republique du Niger)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1966-06-01

    A study based mainly upon field mapping and drill cores examination, followed by a laboratory survey allows us to support a genetic hypothesis upon the formation of analcime in the 'Continental intercalaire' of Agades (Niger). Analcime could be generated from an early diagenesis of argillaceous sediments influenced by high soda content fossil waters inside confined continental sedimentary basins. (authors) [French] Une etude axee essentiellement sur des leves de terrain et des carottes de sondages, suivie d'une etude en laboratoire, permet d'avancer une hypothese genetique sur les formations a analcime du Continental Intercalaire d'AGADES (Niger). L'analcime resulterait d'une diagenese precoce de sediments argileux, sous l'influence d'eaux connees riches en soude, dans des bassins sedimentaires continentaux confines.

  3. Using Remote Sensing and GIS in the Analysis of Ecosystem Decline along the River Niger Basin: The Case of Mali and Niger

    Directory of Open Access Journals (Sweden)

    Edmund C. Merem

    2007-06-01

    Full Text Available In the Sub-Saharan African region of the River Niger Basin, where none of the major rivers is fully contained within the borders of a single nation, riverine ecosystem health monitoring is essential for survival. Even the globally proclaimed goals of sustainability and environmental security in the region are unattainable without using geospatial technologies of remote sensing and Geographic Information Systems (GIS as conduits for environmental health within shared waters. Yet the systematic study of the nature of cooperation between states over shared water resources in troubled areas of the Middle East continues to dominate the literature with minimal coverage of the Sub-Saharan Africa experience and the role of GIS and remote sensing in monitoring the problem. Considering the intense ecosystem stress inflicted on River Niger by human activities and natural forces emanating from upstream and downstream nations. Researching the growing potential for acute riverine ecosystem decline among the nations of Niger and Mali along the River Niger Basin with the latest advances in spatial information technology as a decision support tool not only helps in ecosystem recovery and the avoidance of conflicts, but it has the potentials to bring countries much closer through information exchange. While the nature of the problem remains compounded due to the depletion of available water resources and environmental resources within shared waters, the lack of information exchange extracts ecological costs from all players. This is essential as the Niger Basin nations move towards a multinational watershed management as a conduit for sustainability. To confront these problems, some research questions with relevance to the paper have been posed. The questions include, Have there been any declines in the riverine ecosystem of the study area? What are the effects and what factors trigger the changes? What mitigation measures are in place for dealing with the

  4. BREEDING OF HIGH YIELD STRAIN ASPERGILLUS NIGER 3502 FOR P ECTINASE%果胶酶高产菌株Aspergillus niger 3502的选育

    Institute of Scientific and Technical Information of China (English)

    李廷生; 王平诸; 鲍宇茹

    2001-01-01

    采用紫外线和微波处理黑曲霉(Aspergillus niger) 孢子,获得1株比出发菌株果胶酶产生能力提高2倍的突变株3502;在用正交试验优选而得的最佳固体发酵条件下,酶活力达2 644 u/g.

  5. Mineral potential for incompatible element deposits hosted in pegmatites, alkaline rocks, and carbonatites in the Islamic Republic of Mauritania (phase V, deliverable 87): Chapter Q in Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)

    Science.gov (United States)

    Taylor, Cliff D.; Giles, Stuart A.

    2015-01-01

    Review of PRISM-I documents and the National inventory of mineral occurrences suggests that resources of U, Th, Nb, Ta, Be, rare earth elements (REEs) and fluorite are known in Mauritania and have been exploited in the past at the Bou Naga alkaline complex. Several different deposit types are indicated by the available data. Pegmatitic veins are recorded in several areas of the Archean and Paleoproterozoic portions of the Rgueïbat Shield and are prospective for resources of Li, Be, Nb, Ta, U, Th, and REEs. Over 150 beryl pegmatites are known in the Khnefissat and Inkebden areas of the Chami greenstone belt, and additional concentrations of pegmatites are known in the Guelb Nich Sud area of the Sebkhet Nich greenstone belt and in the northeastern part of the Amsaga Complex. Due to the small size of these deposits, they are unlikely to be economic unless additional value can be gained by processing contained minerals for their industrial uses.

  6. Mineral resources of Australia

    Energy Technology Data Exchange (ETDEWEB)

    Kelsall, D.F.; Woodcock, J.T. (eds.)

    1979-01-01

    The papers presented cover geological, geochemical technology and geophysics in mineral exploration, mineral resources, mining methods and technology, aspects of beneficiation, pyrometallurgy and hydrometallurgy, and environmental aspects. 4 of the 14 papers have been abstracted separately.

  7. Construction Minerals Operations

    Data.gov (United States)

    Department of Homeland Security — This map layer includes construction minerals operations in the United States. The data represent commodities covered by the Minerals Information Team (MIT) of the...

  8. Agricultural Minerals Operations

    Data.gov (United States)

    Department of Homeland Security — This map layer includes agricultural minerals operations in the United States. The data represent commodities covered by the Minerals Information Team (MIT) of the...

  9. Mineral Resources Data System

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Mineral resource occurrence data covering the world, most thoroughly within the U.S. This database contains the records previously provided in the Mineral Resource...

  10. Oxalic acid production by citric acid-producing Aspergillus niger overexpressing the oxaloacetate hydrolase gene oahA.

    Science.gov (United States)

    Kobayashi, Keiichi; Hattori, Takasumi; Honda, Yuki; Kirimura, Kohtaro

    2014-05-01

    The filamentous fungus Aspergillus niger is used worldwide in the industrial production of citric acid. However, under specific cultivation conditions, citric acid-producing strains of A. niger accumulate oxalic acid as a by-product. Oxalic acid is used as a chelator, detergent, or tanning agent. Here, we sought to develop oxalic acid hyperproducers using A. niger as a host. To generate oxalic acid hyperproducers by metabolic engineering, transformants overexpressing the oahA gene, encoding oxaloacetate hydrolase (OAH; EC 3.7.1.1), were constructed in citric acid-producing A. niger WU-2223L as a host. The oxalic acid production capacity of this strain was examined by cultivation of EOAH-1 under conditions appropriate for oxalic acid production with 30 g/l glucose as a carbon source. Under all the cultivation conditions tested, the amount of oxalic acid produced by EOAH-1, a representative oahA-overexpressing transformant, exceeded that produced by A. niger WU-2223L. A. niger WU-2223L and EOAH-1 produced 15.6 and 28.9 g/l oxalic acid, respectively, during the 12-day cultivation period. The yield of oxalic acid for EOAH-1 was 64.2 % of the maximum theoretical yield. Our method for oxalic acid production gave the highest yield of any study reported to date. Therefore, we succeeded in generating oxalic acid hyperproducers by overexpressing a single gene, i.e., oahA, in citric acid-producing A. niger as a host.

  11. Energies and media nr 34. Disaster in Japan. How uranium mines are also useful to Niger; Energies et medias no. 34. Catastrophe au Japon. Comment les mines d'uranium servent aussi le Niger

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-03-15

    After a brief article on the disaster which occurred in Japan (tsunami, nuclear accident in Fukushima, problems faced in Fukushima), this issue addresses the developments induced by the exploitation of uranium mines in Niger: local personnel employment and training, creation of new towns for the personnel, construction of hospitals and roads. The article also addresses the revenues of Niger related to these mines, and the health issue related to mine exploitations (training of authorities in Niger, personnel in charge of radiation protection, personnel and population radioprotection, process residues, water contamination, health monitoring)

  12. Exo-inulinase of Aspergillus niger N402 : A hydrolytic enzyme with significant transfructosylating activity

    NARCIS (Netherlands)

    Goosen, C.; Van der Maarel, M. J. E. C.; Dijkhuizen, L.

    2008-01-01

    The purified exo-inulinase enzyme of Aspergillus niger N402 (AngInuE; heterologously expressed in Escherichia coli) displayed a sucrose:inulin (S/I) hydrolysis ratio of 2.3, characteristic for a typical exo-inulinase. The enzyme also had significant transfructosylating activity with increasing

  13. EFFECT OF SOME ECOLOGICAL FACTORS ON THEGROWTH OF ASPERGILLUS NIGER AND CLADOSPORIUM SPHAEROSPERMUM

    Directory of Open Access Journals (Sweden)

    Ibtisam Mohammed Ababutain

    2013-01-01

    Full Text Available Indoor airborne fungi have been implicated in human health problems, damage to building materials, books, clothes and stored foods, which effected by different ecological factors. Aspergillus niger and Cladosporium sphaerospermum are the most dominant indoor airborne fungi were obtained from our previous study. The effect of normal indoor conditions (Temperature and Relative Humidity on their growth was studied. Including their nutrients growth requirements. The PDA medium was the appropriate growth medium for Cl. sphaerospermum, with a significant difference at (pA. niger, with no significant difference. The temperatures 25 and 30°C favored colony diameter growth for Cl. sphaerospermum and A. niger, respectively with a significant difference at (pCl. sphaerospermum increased to reach its maximum at 100% RH. Whereas, A. niger prefers to grow at lower RH comparing to Cl. sphaerospermum to reach its maximum at 75% RH with a significant difference at (pCl. sphaerospermum can be used as indicator fungi for the high humidity level in residences. The result has proved that keeping the humidity low enough can prevent fungi growth.

  14. Increased NADPH concentration obtained by metabolic engineering of the pentose phosphate pathway in Aspergillus niger

    NARCIS (Netherlands)

    Poulsen, B.R.; Nohr, J.; Douthwaite, S.; Hansen, L.V.; Iversen, J.J.L.; Visser, J.; Ruijter, G.J.G.

    2005-01-01

    Many biosynthetic reactions and bioconversions are limited by low availability of NADPH. With the purpose of increasing the NADPH concentration and/or the flux through the pentose phosphate pathway in Aspergillus niger, the genes encoding glucose 6-phosphate dehydrogenase (gsdA), 6-phosphogluconate

  15. Fumonisin B2 production by Aspergillus niger in Thai coffee beans

    DEFF Research Database (Denmark)

    Noonim, P.; Mahakarnchanaku, W.; Nielsen, Kristian Fog

    2009-01-01

    by black Aspergilli. No Fusarium species known to produce fumonisin were detected, but black Aspergilli had high incidences on both Arabica and Robusta Thai coffee beans. Liquid chromatography (LC) with high-resolution mass spectrometric (HRMS) detection showed that 67% of Aspergillus niger isolates from...

  16. Two New Cerebrosides and Anthraquinone Derivatives from the Marine Fungus Aspergillus niger

    Institute of Scientific and Technical Information of China (English)

    WU Zu-Jian; OUYANG Ming-An; SU Ren-Kuan; KUO Yueh-Hsiung

    2008-01-01

    Two new cerebrosides, asperiamide B (1) and C (2), and two known aflatoxins, averufin and nidurufin, have been isolated from a Quanzhou marine fungus Aspergillus niger (MF-16), and the structures were elucidated by spectroscopic data and chemical means. Among the compounds 5 and 6 showed moderate activities in inhibiting multiplication of the Tobacco Mosaic Virus (TMV).

  17. Polyol synthesis in Aspergillus niger : influence of oxygen availability, carbon and nitrogen sources on the metabolism

    DEFF Research Database (Denmark)

    Diano, Audrey; Bekker-Jensen, S; Dynesen, Jens Østergaard

    2006-01-01

    Polyol production has been studied in Aspergillus niger under different conditions. Fermentations have been run using high concentration of glucose or xylose as carbon source and ammonium or nitrate as nitrogen source. The growth of biomass, as freely dispersed hyphae, led to an increase of medium...

  18. Identification of a Transcription Factor Controlling pH-Dependent Organic Acid Response in Aspergillus niger

    DEFF Research Database (Denmark)

    Poulsen, Lars; Andersen, Mikael Rørdam; Lantz, Anna Eliasson

    2012-01-01

    Acid formation in Aspergillus niger is known to be subjected to tight regulation, and the acid production profiles are fine-tuned to respond to the ambient pH. Based on transcriptome data, putative trans-acting pH responding transcription factors were listed and through knock out studies, mutants...

  19. The effect of organic nitrogen sources on recombinant glucoamylase production by Aspergillus niger in chemostat culture

    NARCIS (Netherlands)

    Swift, R.J.; Karandikar, A.; Griffen, A.M.; Punt, P.J.; Hondel, C.A.M.J.J. van den; Robson, G.D.; Trinci, A.P.J.; Wiebe, M.G.

    2000-01-01

    Aspergillus niger B1, a recombinant strain carrying 20 extra copies of the native glucoamylase gene, was grown in glucose-limited chemostat cultures supplemented with various organic nitrogen sources (dilution rate 0.12 ± 0.01 h-1, pH 5.4). In cultures supplemented with L-alanine, L-methionine, casa

  20. Conversion of fusaric acid to fusarinol by Aspergillus niger: A detoxification reaction

    Science.gov (United States)

    The fungus Fusarium oxysporum causes wilt diseases of plants and produces a potent phytotoxin fusaric acid (FA) which is also toxic to many microorganisms. An Aspergillus strain with high tolerance to FA was isolated from soil. HPLC analysis of culture filtrates from A. niger grown with the addition...

  1. Type III polyketide synthase is involved in the biosynthesis of protocatechuic acid in Aspergillus niger.

    Science.gov (United States)

    Lv, Yangyong; Xiao, Jing; Pan, Li

    2014-11-01

    Genomic studies have shown that not only plants but also filamentous fungi contain type III polyketide synthases. To study the function of type III polyketide synthase (AnPKSIII) in Aspergillus niger, a deletion strain (delAnPKSIII) and an overexpression strain (oeAnPKSIII) were constructed in A. niger MA169.4, a derivative of the wild-type (WT) A. niger ATCC 9029 that produces large quantities of gluconic acid. Alterations in the metabolites were analyzed by HPLC when the extract of the overexpression strain was compared with extracts of the WT and deletion strains. Protocatechuic acid (PCA; 3,4-dihydroxybenzoic acid, 3.2 mg/l) was isolated and identified as the main product of AnPKSIII when inductively expressed in A. niger MA169.4. The molecular weight of PCA was 154.1 (m/z 153.1 [M-H](-)), was detected by ESI-MS in the negative ionization mode, and (1)H and (13)C NMR data confirmed its structure.

  2. Enzymatic Comparisons of Aspergillus niger PhyA and Escherichia coli AppA2 Phytases

    Science.gov (United States)

    This study was to compare three phytase activity assays and kinetics of Aspergillus niger PhyA and Escherichia coli AppA2 phytases expressed in Pichia pastoris at the observed stomach pH of 3.5. In Experiment 1, equivalent phytase activities in the crude preparations of PhyA and AppA2 were tested ...

  3. Ecophysiological characterization of Aspergillus carbonarius, Aspergillus tubingensis and Aspergillus niger isolated from grapes in Spanish vineyards.

    Science.gov (United States)

    García-Cela, E; Crespo-Sempere, A; Ramos, A J; Sanchis, V; Marin, S

    2014-03-03

    The aim of this study was to evaluate the diversity of black aspergilli isolated from berries from different agroclimatic regions of Spain. Growth characterization (in terms of temperature and water activity requirements) of Aspergillus carbonarius, Aspergillus tubingensis and Aspergillus niger was carried out on synthetic grape medium. A. tubingensis and A. niger showed higher maximum temperatures for growth (>45 °C versus 40-42 °C), and lower minimum aw requirements (0.83 aw versus 0.87 aw) than A. carbonarius. No differences in growth boundaries due to their geographical origin were found within A. niger aggregate isolates. Conversely, A. carbonarius isolates from the hotter and drier region grew and produced OTA at lower aw than other isolates. However, little genetic diversity in A. carbonarius was observed for the microsatellites tested and the same sequence of β-tubulin gene was observed; therefore intraspecific variability did not correlate with the geographical origin of the isolates or with their ability to produce OTA. Climatic change prediction points to drier and hotter climatic scenarios where A. tubingensis and A. niger could be even more prevalent over A. carbonarius, since they are better adapted to extreme high temperature and drier conditions.

  4. GalX regulates the d-galactose oxido-reductive pathway in Aspergillus niger

    NARCIS (Netherlands)

    Gruben, B.S.; Zhou, M.; de Vries, R.P.

    2012-01-01

    Galactose catabolism in Aspergillus nidulans is regulated by at least two regulators, GalR and GalX. In Aspergillus niger only GalX is present, and its role in d-galactose catabolism in this fungus was investigated. Phenotypic and gene expression analysis of a wild type and a galX disruptant reveale

  5. Improving Aspergillus niger as a production host through manipulation of pH responding transcription factors

    DEFF Research Database (Denmark)

    Poulsen, Lars; Bruno, K.S.; Thykær, Jette

    ). In the present study the effect of modulation of transcription factors in Aspergillus niger, which is an industrially important micro-organism used in various processes including organic acid and enzyme production, was investigated. The strategy described in this work focuses on regulation connected to p...

  6. An inducible tool for random mutagenesis in Aspergillus niger based on the transposon Vader.

    Science.gov (United States)

    Paun, Linda; Nitsche, Benjamin; Homan, Tim; Ram, Arthur F; Kempken, Frank

    2016-07-01

    The ascomycete Aspergillus niger is widely used in the biotechnology, for instance in producing most of the world's citric acid. It is also known as a major food and feed contaminant. While generation of gene knockouts for functional genomics has become feasible in ku70 mutants, analyzing gene functions or metabolic pathways remains a laborious task. An unbiased transposon-based mutagenesis approach may aid this process of analyzing gene functions by providing mutant libraries in a short time. The Vader transposon is a non-autonomous DNA-transposon, which is activated by the homologous tan1-transposase. However, in the most commonly used lab strain of A. niger (N400 strain and derivatives), we found that the transposase, encoded by the tan1 gene, is mutated and inactive. To establish a Vader transposon-based mutagenesis system in the N400 background, we expressed the functional transposase of A. niger strain CBS 513.88 under the control of an inducible promoter based on the Tet-on system, which is activated in the presence of the antibiotic doxycycline (DOX). Increasing amounts of doxycycline lead to higher Vader excision frequencies, whereas little to none activity of Vader was observed without addition of doxycycline. Hence, this system appears to be suitable for producing stable mutants in the A. niger N400 background.

  7. Characterization of the fumonisin B2 biosynthetic gene cluster in Aspergillus niger and A. awamori.

    Science.gov (United States)

    Aspergillus niger and A. awamori strains isolated from grapes cultivated in Mediterranean basin were examined for fumonisin B2 (FB2) production and presence/absence of sequences within the fumonisin biosynthetic gene (fum) cluster. Presence of 13 regions in the fum cluster was evaluated by PCR assay...

  8. VeA of Aspergillus niger increases spore dispersing capacity by impacting conidiophore architecture.

    Science.gov (United States)

    Wang, Fengfeng; Dijksterhuis, Jan; Wyatt, Timon; Wösten, Han A B; Bleichrodt, Robert-Jan

    2015-01-01

    Aspergillus species are highly abundant fungi worldwide. Their conidia are among the most dominant fungal spores in the air. Conidia are formed in chains on the vesicle of the asexual reproductive structure called the conidiophore. Here, it is shown that the velvet protein VeA of Aspergillus niger maximizes the diameter of the vesicle and the spore chain length. The length and width of the conidiophore stalk and vesicle were reduced nearly twofold in a ΔveA strain. The latter implies a fourfold reduced surface area to develop chains of spores. Over and above this, the conidial chain length was approximately fivefold reduced. The calculated 20-fold reduction in formation of conidia by ΔveA fits the 8- to 17-fold decrease in counted spore numbers. Notably, morphology of the ΔveA conidiophores of A. niger was very similar to that of wild-type Aspergillus sydowii. This suggests that VeA is key in conidiophore architecture diversity in the fungal kingdom. The finding that biomass formation of the A. niger ΔveA strain was reduced twofold shows that VeA not only impacts dispersion capacity but also colonization capacity of A. niger.

  9. Disseminated Aspergillosis due to Aspergillus niger in Immunocompetent Patient: A Case Report

    Directory of Open Access Journals (Sweden)

    Ulku Ergene

    2013-01-01

    Full Text Available Invasive aspergillosis is a major cause of morbidity and mortality in immunocompromised patients. Many cases of pulmonary, cutaneous, cerebral, and paranasal sinus aspergillosis in immunocompetent patient were defined in literature but disseminated aspergillosis is very rare. Here we present an immunocompetent case with extrapulmonary disseminated aspergillosis due to Aspergillus niger, totally recovered after effective antifungal treatment with voriconazole.

  10. NIGERLYSINTM, HEMOLYSIN PRODUCED BY ASPERGILLUS NIGER, CAUSES LETHALITY OF PRIMARY RAT CORTICAL NEURONAL CELLS IN VITRO

    Science.gov (United States)

    Aspergillus niger produced a proteinaceous hemolysin, nigerlysinTM when incubated on sheep's blood agar at both 23° C and 37°C. Nigerlysin was purified from tryptic soy broth culture filtrate. Purified nigerlysin has a molecular weight of approximately 72 kDa, with an...

  11. Simultaneous Production of Amyloglucosidase and Exo-Polygalacturonase by Aspergillus niger in a Rotating Drum Reactor.

    Science.gov (United States)

    Colla, Eliane; Santos, Lucielen Oliveira; Deamici, Kricelle; Magagnin, Glênio; Vendruscolo, Mauricio; Costa, Jorge Alberto Vieira

    2017-02-01

    Simultaneous production of amyloglucosidase (AMG) and exo-polygalacturonase (exo-PG) was carried out by Aspergillus niger in substrate of defatted rice bran in a rotating drum bioreactor (RDB) and studied by a 3(1) × 2(2) factorial experimental design. Variables under study were A. niger strains (A. niger NRRL 3122 and A. niger t0005/007-2), types of inoculum (spore suspension and fermented bran), and types of inducer (starch, pectin, and a mix of both). Solid-state fermentation process (SSF) was conducted at 30 °C under 60-vvm aeration for 96 h in a pilot scale. Production of AMG and exo-PG was significantly affected by the fungal strain and the type of inoculum, but inducers did not trigger any significant effect, an evidence of the fact that these enzymes are constitutive. The maximum activity of exo-PG was 84 U gdm(-1) whereas the maximum yield of AMG was 886.25 U gdm(-1).

  12. Activity and stability of feruloyl esterase A from Aspergillus niger in ionic liquid systems

    DEFF Research Database (Denmark)

    Zeuner, Birgitte; Riisager, Anders; Meyer, Anne S.

    in solvents that favour synthesis over hydrolysis, i.e. systems with low water content such as organic solvents or ionic liquids (ILs). The esterification of sinapic acid with glycerol catalysed by FAE A from Aspergillus niger (AnFaeA) in a series of ILs containing 15% (v/v) buffer showed that An...

  13. Screening a strain of Aspergillus niger and optimization of fermentation conditions for degradation of aflatoxin B₁.

    Science.gov (United States)

    Zhang, Wei; Xue, Beibei; Li, Mengmeng; Mu, Yang; Chen, Zhihui; Li, Jianping; Shan, Anshan

    2014-11-13

    Aflatoxin B₁, a type of highly toxic mycotoxin produced by some species belonging to the Aspergillus genus, such as Aspergillus flavus and Aspergillus parasiticus, is widely distributed in feed matrices. Here, coumarin was used as the sole carbon source to screen microorganism strains that were isolated from types of feed ingredients. Only one isolate (ND-1) was able to degrade aflatoxin B₁ after screening. ND-1 isolate, identified as a strain of Aspergillus niger using phylogenetic analysis on the basis of 18S rDNA, could remove 26.3% of aflatoxin B₁ after 48 h of fermentation in nutrient broth (NB). Optimization of fermentation conditions for aflatoxin B₁ degradation by selected Aspergillus niger was also performed. These results showed that 58.2% of aflatoxin B₁ was degraded after 24 h of culture under the optimal fermentation conditions. The aflatoxin B₁ degradation activity of Aspergillus niger supernatant was significantly stronger than cells and cell extracts. Furthermore, effects of temperature, heat treatment, pH, and metal ions on aflatoxin B₁ degradation by the supernatant were examined. Results indicated that aflatoxin B₁ degradation of Aspergillus niger is enzymatic and this process occurs in the extracellular environment.

  14. Increased NADPH concentration obtained by metabolic engineering of the pentose phosphate pathway in Aspergillus niger

    NARCIS (Netherlands)

    Poulsen, B.R.; Nohr, J.; Douthwaite, S.; Hansen, L.V.; Iversen, J.J.L.; Visser, J.; Ruijter, G.J.G.

    2005-01-01

    Many biosynthetic reactions and bioconversions are limited by low availability of NADPH. With the purpose of increasing the NADPH concentration and/or the flux through the pentose phosphate pathway in Aspergillus niger, the genes encoding glucose 6-phosphate dehydrogenase (gsdA), 6-phosphogluconate

  15. The effect of environmental conditions on extracellular protease activity in controlled fermentations of Aspergillus niger

    NARCIS (Netherlands)

    Braaksma, M.; Smilde, A.K.; Werf, M.J. van der; Punt, P.J.

    2009-01-01

    Proteolytic degradation by host proteases is one of the key issues in the application of filamentous fungi for non-fungal protein production. In this study the influence of several environmental factors on the production of extracellular proteases of Aspergillus niger was investigated systematically

  16. The structure and expression of the pyruvatekinase gene of Aspergillus nidulans and Aspergillus niger.

    NARCIS (Netherlands)

    Graaff, de L.H.

    1989-01-01

    Dit proefschrift "Het pyruvaat kinase gen en zijn expressie in Aspergillus nidulans en Aspergillus niger " beschrijft het onderzoek naar de structuur en expressie van het pyruvaat kinase gen in deze schimmels.De doelstelling van dit onderzoek was de opheldering van de genstructuur van het pyruvaat k

  17. The identity of the enigmatic "Black Shrew" (Sorex niger Ord, 1815)

    Science.gov (United States)

    Woodman, Neal

    2013-01-01

    The scientific name Sorex niger Ord, 1815 (Mammalia, Soricidae) was originally applied to a North American species that George Ord called the “Black Shrew.” The origin of the name “Black Shrew,” however, was obscure, and Samuel Rhoads subsequently wrote that the species represented by this name could not be determined. The names Sorex niger Ord and Black Shrew have since been mostly forgotten. Two of Ord's contemporaries, however, noted that Ord's use of these names probably alluded to Benjamin Smith Barton's Black Shrew, whose discovery near Philadelphia was announced by Barton in 1806. Examination of two unpublished illustrations of the Black Shrew made by Barton indicates that the animal depicted is Blarina brevicauda (Say, 1822). Had the connection between Ord's and Barton's names been made more clearly, one of the most common mammals in eastern North America would bear a different scientific name today. This connection also would have affected the validity of Sorex niger Horsfield, 1851. While Sorex niger Ord remains a nomen nudum, the animal it referenced can now be identified.

  18. Induction, isolation, and characterization of aspergillus niger mutant strains producing elevated levels of beta-galactosidase.

    OpenAIRE

    1981-01-01

    An Aspergillus niger mutant strain, VTT-D-80144, with an improvement of three- to fourfold in the production of extracellular beta-galactosidase was isolated after mutagenesis. The production of beta-galactosidase by this mutant was unaffected by fermentor size, and the enzyme was also suitable for immobilization.

  19. Biocatalytic potential of laccase-like multicopper oxidases from Aspergillus niger

    NARCIS (Netherlands)

    Tamayo Ramos, J.A.; Berkel, van W.J.H.; Graaff, de L.H.

    2012-01-01

    BACKGROUND: Laccase-like multicopper oxidases have been reported in several Aspergillus species but they remain uncharacterized. The biocatalytic potential of the Aspergillus niger fungal pigment multicopper oxidases McoA and McoB and ascomycete laccase McoG was investigated. RESULTS: The laccase-li

  20. Inorganic ions in the medium modify tropane alkaloids and riboflavin output in Hyoscyamus niger root cultures

    Directory of Open Access Journals (Sweden)

    Katrin Pudersell

    2012-01-01

    Full Text Available Context: Hyoscyamus niger L. (Solanaceae roots are rich of tropane alkaloids, such as hyoscyamine and scopolamine are used as the source of raw material for the pharmaceutical industry. Aims: The aim of the present study was to investigate the effect of calcium, magnesium, and iron ions on the production of tropane alkaloids and excretion of riboflavin in H. niger root cultures. Materials and Methods: The calcium, magnesium, or iron enriched/deprived Murashige and Skoog (MS growth medium were used for culture of H. niger root tissues. The secondary metabolites were quantified using high performance liquid chromatography with ultraviolet detector (HPLC-UV and fluorimetry techniques. Results: An increased calcium content in the medium unidirectionally reduced hyoscyamine, while increasing scopolamine production with only a moderate impact on riboflavin excretion. Manipulations with magnesium and iron contents in the medium resulted in divergent changes in hyoscyamine, scopolamine, and riboflavin concentrations. Conclusions: Our results show that increased calcium ion content in the Murashige and Skoog medium may be used for the intensification of the scopolamine production in H. niger root cultures.

  1. The transcriptomic fingerprint of glucoamylase over-expression in Aspergillus niger

    NARCIS (Netherlands)

    Kwon, M.J.; Jorgensen, T.R.; Nitsche, B.M.; Arentshorst, M.; Park, J.; Ram, A.F.J.; Meyer, V.

    2012-01-01

    Background: Filamentous fungi such as Aspergillus niger are well known for their exceptionally high capacity for secretion of proteins, organic acids, and secondary metabolites and they are therefore used in biotechnology as versatile microbial production platforms. However, system-wide insights int

  2. Black Terns Chlidonias niger and their dietary problems in Dutch wetlands

    NARCIS (Netherlands)

    Beintema, A.; Baarspul, T.; Krijger, J.P.; Van Oers, K.; Keller, Marek

    2010-01-01

    Black Terns Chlidonias niger have shown a decrease of well over 90% as a breeding bird in The Netherlands during the twentieth century. Two hypotheses have been put forward for this decline: the disappearance of the floating plant Water Soldier Stratiotes aloides, which used to be the favourite

  3. Aspergillus niger membrane-associated proteome analysis for the identification of glucose transporters

    NARCIS (Netherlands)

    Sloothaak, J.; Odoni, D.I.; Graaff, de L.H.; Martins dos Santos, V.A.P.; Schaap, P.J.; Tamayo Ramos, J.A.

    2015-01-01

    BACKGROUND: The development of biological processes that replace the existing petrochemical-based industry is one of the biggest challenges in biotechnology. Aspergillus niger is one of the main industrial producers of lignocellulolytic enzymes, which are used in the conversion of lignocellulosic fe

  4. Fertility management and landscape position: farmers' use of nutrient sources in western Niger and possible improvements

    NARCIS (Netherlands)

    Gandah, M.; Brouwer, J.; Duivenbooden, van N.; Hiernaux, P.

    2003-01-01

    Poor millet growth and yields in Niger are commonly attributed to rainfall deficits and low soil nutrient content. Land management by local farmers is done as a function of soil types, crops, and available resources. Farmer management practices in millet fields located on four different landscape

  5. Repeat induced point mutation in two asexual fungi, Aspergillus niger and Penicillium chrysogenum.

    Science.gov (United States)

    Braumann, Ilka; van den Berg, Marco; Kempken, Frank

    2008-05-01

    Repeat induced point mutation (RIP) is a gene silencing mechanism present in fungal genomes. During RIP, duplicated sequences are efficiently and irreversibly mutated by transitions from C:G to T:A. For the first time, we have identified traces of RIP in transposable elements of Aspergillus niger and Penicillium chrysogenum, two biotechnologically relevant fungi. We found that RIP in P. chrysogenum has affected a large set of sequences, which also contain other mutations. On the other hand, RIP in A. niger is limited to only few sequences, but literally all mutations are RIP-like. Surprisingly, RIP occurred only in transposon sequences that have disrupted open reading frames in A. niger, a phenomenon not yet reported for other fungi. In both fungal species, we identified two sequences with strong sequence similarity to Neurospora crassa RID. RID is a putative DNA methyltransferase and the only known enzyme involved in the RIP process. Our findings suggest that both A. niger and P. chrysogenum either had a sexual past or have a sexual potential. These findings have important implications for future strain development of these fungi.

  6. A molecular analysis of L-arabinan degradation in Aspergillus niger and Aspergillus nidulans.

    NARCIS (Netherlands)

    Flipphi, M.J.A.

    1995-01-01

    This thesis describes a molecular study of the genetics ofL-arabinan degradation in Aspergillus niger and Aspergillus nidulans. These saprophytic hyphal fungi produce an extracellular hydrolytic enzyme system to depolymerize the plant cell wall polysaccharideL<

  7. The Place of Bonny in Niger Delta History (Pp. 36-45)

    African Journals Online (AJOL)

    User

    State University of Education, Rumuolumeni, Port Harcourt, Nigeria. Tel: + ... of this unique settlement on the Rio Real of Eastern Delta and its implications for the .... present settlement at Okoloama near the Niger Delta coast after a brief stay .... enterprise took place in the Bonny Sea and various creeks and ponds where.

  8. Water Supply Deficiency and Implications for Rural Development in the Niger-Delta Region of Nigeria

    Science.gov (United States)

    Nkwocha, E. E.

    2009-01-01

    There is a growing concern about the marginalization of the Niger Delta region of Nigeria in terms of infrastructural and social services provision. This study examined the water supply deficiency and its general implications for rural development within the region. Data and other study characteristics were extracted from 501 subjects drawn from…

  9. Communications Channels in the Sahel Using Mauritania, Mali, Niger, and Chad as a Case Study

    Science.gov (United States)

    2007-05-01

    Page 60 of 107 Appendix B - Phone Card Distribution Chain Phone Card Provider Internet Cafes ...92 Malaysia 22,25 93 Comoros 22,50 - Zambia 22,50 95 Niger 24,50 - Seychelles 24,50 97 Morocco 24,83 98 Bhutan 25,00 - Côte d’Ivoire 25,00

  10. Development of tools for quantitative intracellular metabolomics of Aspergillus niger chemostat cultures

    NARCIS (Netherlands)

    Lameiras, F.; Heijnen, J.J.; Van Gulik, W.M.

    2015-01-01

    In view of the high citric acid production capacity of Aspergillus niger, it should be well suited as a cell factory for the production of other relevant acids as succinic, fumaric, itaconic and malic. Quantitative metabolomics is an important omics tool in a synthetic biology approach to develop A.

  11. Porosity prediction of I-field in the Niger delta area using well-log ...

    African Journals Online (AJOL)

    Porosity prediction of I-field in the Niger delta area using well-log data and ... There are many important characteristics of formations within the subsurface that can ... and 4.8186oN, longitudes 6.9595oE and 6.9800oE. Variogram analysis and ...

  12. Exo-inulinase of Aspergillus niger N402: A hydrolytic enzyme with significant transfructosylating activity

    NARCIS (Netherlands)

    Goosen, C.; Maarel, M.J. E.C. van der; Dijkhuizen, L.

    2008-01-01

    The purified exo-inulinase enzyme of Aspergillus niger N402 (AngInuE; heterologously expressed in Escherichia coli) displayed a sucrose:inulin (S/I) hydrolysis ratio of 2.3, characteristic for a typical exo-inulinase. The enzyme also had significant transfructosylating activity with increasing

  13. Towards ending conflict and insecurity in the Niger Delta region: A ...

    African Journals Online (AJOL)

    2017-08-28

    Aug 28, 2017 ... life insecure. In the Niger Delta, violence has been the bane of the region .... outside the country and during the period, relative peace returned to the ... to new lands … while decreases in wealth can cause deprivation conflicts.

  14. Arabinase induction and carbon catabolite repression in Aspergillus niger and Aspergillus nidulans.

    NARCIS (Netherlands)

    Veen, van der P.

    1995-01-01

    The first aim of this thesis was to get a better understanding of the properties and the induction features of arabinan degrading enzymes and enzymes involved in the intracellular L-arabinose catabolic pathway in Aspergillus niger. The second aim was to understand the which role carbon catabolite re

  15. Heterologous expression of the Aspergillus nidulans alcR-alcA system in Aspergillus niger

    NARCIS (Netherlands)

    Nikolaev, I.; Mathieu, M.; Vondervoort, van de P.J.I.; Visser, J.; Felenbok, B.

    2002-01-01

    The inducible and strongly expressed alcA gene encoding alcohol dehydrogenase I from Aspergillus nidulans was transferred together with the activator gene alcR, in the industrial fungus Aspergillus niger. This latter organism does not possess an inducible alc system but has an endogenously constitut

  16. Regulation of expression of the Aspergillus niger benzoate para-hydroxylase cytochrome P450 system

    NARCIS (Netherlands)

    Brink, J.M. van den; Punt, P.J.; Gorcom, R.F.M. van; Hondel, C.A.M.J.J. van den

    2000-01-01

    Cytochrome P450 enzyme systems are found throughout nature and are involved in many different, often complex, bioconversions. In the endoplasmic reticulum of the filamentous fungus Aspergillus niger a cytochrome P450 enzyme system is present that is capable of the para-hydroxylation of benzoate. The

  17. Alienation and Militancy in the Niger Delta : Hostage Taking and the ...

    African Journals Online (AJOL)

    through a neglect of development, and promotion of political thuggery in the electoral .... in relation to hostage taking in the Niger Delta. The third section ...... Delhi, India: Macmillan,. India Limited. .... Ile Ife: University of Ife Press. Worika, I.L. ...

  18. The role of Tilapia in food security of fishing villages in Niger state ...

    African Journals Online (AJOL)

    The role of Tilapia in food security of fishing villages in Niger state, Nigeria. ... the form of fish cooked (fresh, smoked, dried) and the source of fish (whether ... purchased in the market or caught directly by household members from local rivers).

  19. Towards Deriving Renewable Energy from Aquatic Macrophytes Polluting Water Bodies in Niger Delta Region of Nigeria

    Directory of Open Access Journals (Sweden)

    Badmus Abdurrahman Adeleye

    2013-01-01

    Full Text Available This study was performed to derive methane rich biogas from biomass of harvested water hyacinth polluting water bodies in selected rivers of the Niger delta region of Nigeria. Field visits were undertaken on selected rivers in the Niger Delta region in which aquatic macrophytes were collected and inventorized. Also different types of aquatic macrophytes were surveyed. Control by harvesting macrophytes and deriving energy (methane-rich biogas from biomass of one (water hyacinth was successfully carried out in this study. An initial test was conducted to evaluate methane rich biogas production from water hyacinth collected from the wild. After a successful production of combustible biogas, laboratory experiments aimed at generating biogas from harvested biomass of aquatic mycrophyte (water hyacinth cultivated under eutrophic and oligotrophic conditions were undertaken in the laboratory. The result of the study showed highest biogas yield of 22 L over a 40 day retention time for water hyacinth raised under eutrophic conditions. Biogas yield for water hyacinth raised under oligotrophic conditions recorded the highest yield of 53L over an 11 day retention time. The conversion of the biomass of harvested aquatic macrophyte (water hyacinth from the Niger Delta into renewable energy, that is combustible biogas, demonstrated an inevitable option for the control and management of environmental pollution associated with aquatic macrophytes and their usability for poverty alleviation in the Niger Delta region of Nigeria.

  20. Salmonella biofilm formation on Aspergillus niger involves cellulose--chitin interactions.

    Directory of Open Access Journals (Sweden)

    Maria T Brandl

    Full Text Available Salmonella cycles between host and nonhost environments, where it can become an active member of complex microbial communities. The role of fungi in the environmental adaptation of enteric pathogens remains relatively unexplored. We have discovered that S. enterica Typhimurium rapidly attaches to and forms biofilms on the hyphae of the common fungus, Aspergillus niger. Several Salmonella enterica serovars displayed a similar interaction, whereas other bacterial species were unable to bind to the fungus. Bacterial attachment to chitin, a major constituent of fungal cell walls, mirrored this specificity. Pre-incubation of S. Typhimurium with N-acetylglucosamine, the monomeric component of chitin, reduced binding to chitin beads by as much as 727-fold and inhibited attachment to A. niger hyphae considerably. A cellulose-deficient mutant of S. Typhimurium failed to attach to chitin beads and to the fungus. Complementation of this mutant with the cellulose operon restored binding to chitin beads to 79% of that of the parental strain and allowed for attachment and biofilm formation on A. niger, indicating that cellulose is involved in bacterial attachment to the fungus via the chitin component of its cell wall. In contrast to cellulose, S. Typhimurium curli fimbriae were not required for attachment and biofilm development on the hyphae but were critical for its stability. Our results suggest that cellulose-chitin interactions are required for the production of mixed Salmonella-A. niger biofilms, and support the hypothesis that encounters with chitinaceous alternate hosts may contribute to the ecological success of human pathogens.

  1. An antifungal role of hydrogen sulfide on the postharvest pathogens Aspergillus niger and Penicillium italicum.

    Directory of Open Access Journals (Sweden)

    Liu-Hui Fu

    Full Text Available In this research, the antifungal role of hydrogen sulfide (H2S on the postharvest pathogens Aspergillus niger and Penicillium italicum growing on fruits and under culture conditions on defined media was investigated. Our results show that H2S, released by sodium hydrosulfide (NaHS effectively reduced the postharvest decay of fruits induced by A. niger and P. italicum. Furthermore, H2S inhibited spore germination, germ tube elongation, mycelial growth, and produced abnormal mycelial contractions when the fungi were grown on defined media in Petri plates. Further studies showed that H2S could cause an increase in intracellular reactive oxygen species (ROS in A. niger. In accordance with this observation we show that enzyme activities and the expression of superoxide dismutase (SOD and catalase (CAT genes in A. niger treated with H2S were lower than those in control. Moreover, H2S also significantly inhibited the growth of Saccharomyces cerevisiae, Rhizopus oryzae, the human pathogen Candida albicans, and several food-borne bacteria. We also found that short time exposure of H2S showed a microbicidal role rather than just inhibiting the growth of microbes. Taken together, this study suggests the potential value of H2S in reducing postharvest loss and food spoilage caused by microbe propagation.

  2. Molecular and biochemical characterization of a novel intracellular invertase from Aspergillus niger with transfructosylating activity

    NARCIS (Netherlands)

    Yuan, Xiao-Lian; van Munster, Jolanda M.; Ram, Arthur F. J.; van der Maarel, Marc J. E. C.; Dijkhuizen, Lubbert; Goosen, C.

    2007-01-01

    A novel subfamily of putative intracellular invertase enzymes (glycoside hydrolase family 32) has previously been identified in fungal genomes. Here, we report phylogenetic, molecular, and biochemical characteristics of SucB, one of two novel intracellular invertases identified in Aspergillus niger.

  3. Black Terns Chlidonias niger and their dietary problems in Dutch wetlands

    NARCIS (Netherlands)

    Beintema, Albert J.; van der Winden, Jan; Baarspul, Teun; de Krijger, Jan Pieter; van Oers, Kees; Keller, Marek

    2010-01-01

    Black Terns Chlidonias niger have shown a decrease of well over 90% as a breeding bird in The Netherlands during the twentieth century. Two hypotheses have been put forward for this decline: the disappearance of the floating plant Water Soldier Stratiotes aloides, which used to be the favourite nest

  4. Crystallization and Preliminary Crystallographic Characterization of Endo-polygalacturonase II from Aspergillus niger

    NARCIS (Netherlands)

    Schröter, K.-H.; Arkema, A.; Kester, H.C.M.; Visser, J.; Dijkstra, B.W.

    1994-01-01

    The endo-polygalacturonase II from Aspergillus niger has been crystallized from an ammonium sulfate solution by the hanging drop method. The crystals belong to the monoclinic space group P2(1), with cell dimensions a = 60.6 Angstrom, b = 152.6 Angstrom, c = 74.0 Angstrom and beta = 91.2 degrees with

  5. Exo-inulinase of Aspergillus niger N402: A hydrolytic enzyme with significant transfructosylating activity

    NARCIS (Netherlands)

    Goosen, C.; Maarel, M.J. E.C. van der; Dijkhuizen, L.

    2008-01-01

    The purified exo-inulinase enzyme of Aspergillus niger N402 (AngInuE; heterologously expressed in Escherichia coli) displayed a sucrose:inulin (S/I) hydrolysis ratio of 2.3, characteristic for a typical exo-inulinase. The enzyme also had significant transfructosylating activity with increasing sucro

  6. Oil, migration, and the political economy of HIV/AIDS prevention in Nigeria's Niger Delta.

    Science.gov (United States)

    Udoh, Isidore A

    2013-01-01

    In most of sub-Saharan Africa, HIV/AIDS is driven by endemic structural problems such as unemployment, poverty, forced migration, sexual exploitation, and concurrent sexual partnerships. In the Niger Delta of Nigeria, the epidemic is exacerbated by recurring regional conflict and negative environmental externalities resulting from 50 years of oil exploration. This article seeks to identify and analyze potential barriers to HIV/AIDS prevention and treatment from oil pollution and other environmental stressors in Nigeria's Niger Delta. We develop a conceptual framework to understand how oil politics and economic systems affect HIV risks in Nigeria. We then evaluate evidence of how environmental exposures can amplify risks. Using 10 semi-structured interviews, with 85 focus group participants, we test the argument that HIV transmission in the Niger Delta is related to a manipulative "divide and rule" power dynamic that characterizes multinational oil companies' role in shaping conflict contours in oil communities. Oil exploration destroys livelihoods, institutions, and values and forces impoverished and illiterate girls and women to migrate or be trafficked to urban centers as child laborers and sex workers. The elevated HIV/AIDS risk in the Niger Delta brings into focus the political economy of resource extraction, globalization, and indigenous, minority rights and struggles.

  7. Simultaneous amyloglucosidase and exo-polygalacturonase production by Aspergillus niger using solid-state fermentation

    Directory of Open Access Journals (Sweden)

    Jorge Alberto Vieira Costa

    2007-09-01

    Full Text Available Amyloglucosidase (AMG and exo-polygalacturonase (exo-PG were simultaneously produced by two different strains of Aspergillus niger in solid-state fermentation (SSF using defatted rice-bran as substrate. The effect of Aspergillus niger strain (t0005/007-2 and/or CCT 3312, inoculum type (spore suspension or fermented bran and addition of inducers (pectin and/or starch to the culture media was studied using a 3² x 2¹ factorial experimental design. The production of AMG and exo-PG was significantly affected by fungal strain and inoculum type but inducers had no effect. The maximum yields obtained were 1310 U/g dm for AMG using a spore suspension of A. niger CCT 3312 and 50.2 U/g dm for exo-PG production, using A. niger t0005/007-2 and fermented bran as inoculum. The yields obtained represented acceptable values in comparison with data available in the literature and indicated that defatted rice-bran was a good nutrient source.As enzimas amiloglicosidase (AMG e exo-poligalacturonase (exo-PG foram produzidas simultaneamente por duas cepas de Aspergillus niger, através de fermentação em estado sólido usando farelo de arroz desengordurado como substrato. Foram avaliados os efeitos da cepa de Aspergillus niger, tipo de inóculo e adição de indutores no meio de cultura, utilizando-se um planejamento experimental fracionário 3² x 2¹. O máximo rendimento obtido foi 1310 U/g ms para a produção de AMG e 50,2 U/g ms para a exo-PG. Comparando-se estes resultados com dados da literatura pode-se dizer que os rendimentos obtidos foram aceitáveis e indicam que o farelo de arroz desengordurado é uma boa fonte de nutrientes. A produção de AMG e exo-PG foi significativamente afetada pelas variáveis cepa de A. niger e tipo de inóculo, enquanto a variável indutor não apresentou influência significativa na produção destas enzimas.

  8. PENAMBAHAN MIKROBA, Aspergillus niger DALAM BUNGKIL KELAPA SAWIT SEBAGAI BAHAN BAKU PAKAN UNTUK PEMBESARAN IKAN KERAPU MACAN

    Directory of Open Access Journals (Sweden)

    Neltje Nobertine Palinggi

    2008-12-01

    Full Text Available Penelitian ini dilakukan untuk mendapatkan informasi tentang pengaruh dosis Aspergillus niger dalam bungkil kelapa sawit sebagai bahan pakan pada pembesaran ikan kerapu macan. Ikan uji yang digunakan berukuran bobot rata-rata 23,15±0,23 g; ditebar dalam keramba jaring apung ukuran 1 m x 1 m x 2 m, dengan kepadatan 16 ekor/keramba. Perlakuan yang diuji adalah penambahan Aspergillus niger sebanyak 2, 4, 8, 16 g/kg bungkil kelapa sawit dan kontrol. Masing-masing perlakuan diulang tiga kali dan disain adalah rancangan acak lengkap. Selama pemeliharaan, ikan diberi pakan uji dua kali sehari (pagi dan sore secara satiasi selama 20 minggu. Hasil penelitian menunjukkan bahwa penambahan 8 g Aspergillus niger/kg bungkil kelapa sawit memberikan pertambahan bobot dan laju spesifik lebih tinggi daripada kontrol (P0,05, namun nilainya nyata lebih tinggi (P0.05 among those of the juveniles fed on the diets with 2, 4, 16 g of A. niger/kg palm oil cake. Although the feed efficiency, protein efficiency ratio and protein retention of juveniles fed on the diet with 8 g A. niger/kg palm oil cake were not significantly different (P>0.05 from those of the juveniles fed on the diets with 2 and 4 g of A. niger/kg palm oil cake, those of juveniles the fed diet with 8 g of A. niger/kg palm oil cake were significantly higher (P<0.05 than those of the juveniles fed the diet with 16 g A. niger/kg palm oil cake. The best of growth rate of tiger grouper juveniles occurred at the dosage of 7.8—8.2 g A. niger/kg palm oil cake.

  9. Mineral Supply Challenges

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Faced with shortcomings in its mineral supply, it’s imperative for China to balance its desire for reserves with its current economic needs Mineral resources are the corner- stone of materials needed for China’s national economic and social development.The country even counts on its mineral resources to satisfy 90 percent of its energy demands and over 95

  10. Q emocratic Republic of the Congo:

    African Journals Online (AJOL)

    Women and Peace-building in the Democratic Republic of the Congo .... Former Yugoslavia, Burundi, Northern Ireland and India and Pakistan. In the ..... we would have thought it was time to talk about sexual violence against women.

  11. Internal displacement in the Central African Republic

    Directory of Open Access Journals (Sweden)

    Laura Perez

    2008-12-01

    Full Text Available In the Central African Republic (CAR, where mostdisplaced people are unaware of their rights, the NorwegianRefugee Council (NRC is seeking to promote widerawareness of, and respect for, the Guiding Principles.

  12. Physicochemical Properties Analysis and Secretome of Aspergillus niger in Fermented Rapeseed Meal.

    Science.gov (United States)

    Shi, Changyou; He, Jun; Yu, Jie; Yu, Bing; Mao, Xiangbing; Zheng, Ping; Huang, Zhiqing; Chen, Daiwen

    2016-01-01

    The nutrient digestibility and feeding value of rapeseed meal (RSM) for non-ruminant animals is poor due to the presence of anti-nutritional substances such as glucosinolate, phytic acid, crude fiber etc. In the present study, a solid state fermentation (SSF) using Aspergillus niger was carried out with the purpose of improving the nutritional quality of RSM. The chemical composition and physicochemical properties of RSM before and after fermentation were compared. To further understand possible mechanism of solid state fermentation, the composition of extracellular enzymes secreted by Aspergillus niger during fermentation was analysed using two-dimentional difference gel electrophoresis (2D-DIGE) combined with matrix assisted laser desorption ionization-time of flight-mass spectrometer (MALDI-TOF-MS). Results of the present study indicated that SSF had significant effects on chemical composition of RSM. The fermented rapeseed meal (FRSM) contained more crude protein (CP) and amino acid (AA) (except His) than unfermented RSM. Notably, the small peptide in FRSM was 2.26 time larger than that in unfermented RSM. Concentrations of anti-nutritional substrates in FRSM including neutral detergent fiber (NDF), glucosinolates, isothiocyanate, oxazolidithione, and phytic acid declined (P niger fermentation disrupted the surface structure, changed macromolecular organic compounds, and reduced the protein molecular weights of RSM substrate. Total proteins of raw RSM and FRSM were separated and 51 protein spots were selected for mass spectrometry according to 2D-DIGE map. In identified proteins, there were 15 extracellular hydrolases secreted by A. niger including glucoamylase, acid protease, beta-glucanase, arabinofuranosidase, xylanase, and phytase. Some antioxidant related enzymes also were identified. These findings suggested that A. niger is able to secrete many extracellular degradation enzymes (especially lignocellulosic hydrolyzing enzymes, acid proteases and phytase

  13. Identification of Genes Associated with Morphology in Aspergillus Niger by Using Suppression Subtractive Hybridization

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Ziyu; Mao, Xingxue; Magnuson, Jon K.; Lasure, Linda L.

    2004-04-01

    The morphology of citric acid production strains of Aspergillus niger is sensitive to a variety of factors including the concentration of manganese (Mn2+). Upon increasing the Mn2+ concentration in A. niger (ATCC 11414) cultures to 14 ppb or higher, the morphology switches from pelleted to filamentous, accompanied by a rapid decline in citric acid production. Molecular mechanisms through which Mn2+ exerts effects on morphology and citric acid production in A. niger have not been well defined, but our use of suppression subtractive hybridization has identified 22 genes responsive to Mn2+. Fifteen genes were differentially expressed when A. niger was grown in media containing 1000 ppb Mn2+ (filamentous form) and seven genes in 10 ppb Mn2+ (pelleted form). Of the fifteen filamentous-associated genes, seven are novel and eight share 47-100% identity to genes from other organisms. Five of the pellet-associated genes are novel, and the other two genes encode a pepsin-type protease and polyubiquitin. All ten genes with deduced functions are either involved in amino acid metabolism/protein catabolism or cell regulatory processes. Northern-blot analysis showed that the transcripts of all 22 genes were rapidly enhanced or suppressed by Mn2+. Steady-state mRNA levels of six selected filamentous associated genes remained high during five days of culture in a filamentous state and low under pelleted growth conditions. The opposite behavior was observed for four selected pellet-associated genes. The full-length cDNA of the filamentous-associated clone, Brsa-25 was isolated. Antisense expression of Brsa-25 permitted pelleted growth and increased citrate production at higher concentrations of Mn2+ than could be tolerated by the parent strain. The results suggest the involvement of the newly isolated genes in regulation of A. niger morphology.

  14. Gene overexpression and biochemical characterization of the biotechnologically relevant chlorogenic acid hydrolase from Aspergillus niger.

    Science.gov (United States)

    Benoit, Isabelle; Asther, Michèle; Bourne, Yves; Navarro, David; Canaan, Stéphane; Lesage-Meessen, Laurence; Herweijer, Marga; Coutinho, Pedro M; Asther, Marcel; Record, Eric

    2007-09-01

    The full-length gene that encodes the chlorogenic acid hydrolase from Aspergillus niger CIRM BRFM 131 was cloned by PCR based on the genome of the strain A. niger CBS 513.88. The complete gene consists of 1,715 bp and codes for a deduced protein of 512 amino acids with a molecular mass of 55,264 Da and an acidic pI of 4.6. The gene was successfully cloned and overexpressed in A. niger to yield 1.25 g liter(-1), i.e., 330-fold higher than the production of wild-type strain A. niger CIRM BRFM131. The histidine-tagged recombinant ChlE protein was purified to homogeneity via a single chromatography step, and its main biochemical properties were characterized. The molecular size of the protein checked by mass spectroscopy was 74,553 Da, suggesting the presence of glycosylation. ChlE is assembled in a tetrameric form with several acidic isoforms with pIs of around 4.55 and 5.2. Other characteristics, such as optimal pH and temperature, were found to be similar to those determined for the previously characterized chlorogenic acid hydrolase of A. niger CIRM BRFM 131. However, there was a significant temperature stability difference in favor of the recombinant protein. ChlE exhibits a catalytic efficiency of 12.5 x 10(6) M(-1) s(-1) toward chlorogenic acid (CGA), and its ability to release caffeic acid from CGA present in agricultural by-products such as apple marc and coffee pulp was clearly demonstrated, confirming the high potential of this enzyme.

  15. Crystal structure and chemistry of natural kutinaite from Černý Důl, Krkonoše, Czech Republic

    DEFF Research Database (Denmark)

    Bindi, Luca; Makovicky, Emil

    2015-01-01

    We have characterized the crystal structure of natural kutinaite, a rare mineral from the ores of Černý Důl, Czech Republic, by single-crystal X-ray diffraction and chemical analysis. We found that the structure of natural kutinaite is not identical to that of synthetic Cu14Ag6As7, previously...

  16. Grey Literature in the Czech Republic

    OpenAIRE

    Pejsova, Petra (NTK); Pfeiferova, Martina (NTK); GreyNet, Grey Literature Network Service

    2008-01-01

    Our contribution summarizes and describes activities concerning grey literature in the Czech Republic. The managing organisation of the activity is the State Technical Library (henceforth the STL); in the past, it was the STL, who was collecting, publishing and submitting grey literature into the SIGLE system. Moreover, the STL was the representative of the Czech Republic in the EAGLE. Now, EAGLE being extinct, there is no coordinated collection of grey literature on the national level since ...

  17. The Skinhead Subculture in the Czech Republic

    OpenAIRE

    Smolík, Josef

    2015-01-01

    This article briefly describes the skinhead subculture, its history, components, characteristics, values, attitudes and norms. It also presents the various currents of the subculture, with an emphasis on the current apolitical trend within this subculture. The article discusses not only the skinhead subculture in England (its roots, development, etc.), but also the situation in the Czech Republic. The skinhead scene in the Czech Republic is characterised by disunity, caused by political...

  18. Holocene palaeoenvironmental changes in the central Sahara (NE-Niger)

    Science.gov (United States)

    Brauneck, J.; Baumhauer, R.

    2009-04-01

    Although a high number of investigations focussed on the succession of climatological conditions in the Central Sahara, some uncertainties still exist as some of the results show discontinuities and mostly are of low temporal and spatial resolution. Two expeditions in 2005 and 2006 headed to the northeastern parts of Niger to investigate the known remains of palaeolakes and search some new and undetected ones. The sediments found at several sites were investigated in order to receive a complete picture of the Late Quaternary environmental settings and to produce high-resolution proxies for palaeoclimate modelling. The most valuable and best-investigated study site is the sebkha of Seggedim, where a core of 15 meters length could be extracted which revealed a composition of high-resolution sections. Stratigraphical, structural and geochemical investigations as well as the analysis of thin sections allow the characterisation of different environmental conditions throughout the core. Most importantly, a complex age-depth model could be constructed, based on 21 accelerator mass spectrometry (AMS) radiocarbon measurements and reaching from Early to Mid Holocene. Driven by climate and hydrogeological influence, the water body developed from a water pond of several metres depth within a stable, grass and shrub vegetated landscape, to a freshwater lake in a more dynamic environmental setting. Radiocarbon dates set the beginning of the stage at about 10.6 ka cal BP, with an exceptionally stable regime to 6.6 ka cal BP (at 12.6 metres' depth), when a major change in the sedimentation regime of the basin is recorded in the core. Increased erosion, likely due to decreased vegetation cover within the basin, led to the filling of the lake within a few hundred years and the subsequent development of a sebkha due to massive evaporation. Due to the lack of dateable material in the upper core section, the termination of the lake stage and the onset of the subsequent sebkha stage

  19. Chelated minerals for poultry

    Directory of Open Access Journals (Sweden)

    SL Vieira

    2008-06-01

    Full Text Available Organic minerals have been subject of an increasing number of investigations recently. These compounds can be considered the most significant event regarding commercial forms of minerals targeting animal supplementation in the last decades. Minerals, especially metals, are usually supplemented in poultry feeds using cheap saline sources and have never required a lot of attention in terms of quality. On the other hand, definitions of organic minerals are very broad and frequently lead to confusion when decision-making becomes necessary. Organic minerals include any mineral bound to organic compounds, regardless of the type of existing bond between mineral and organic molecules. Proteins and carbohydrates are the most frequent candidates in organic mineral combinations. Organic fraction size and bond type are not limitations in organic mineral definition; however, essential metals (Cu, Fe, Zn, and Mn can form coordinated bonds, which are stable in intestinal lumen. Metals bound to organic ligands by coordinated bonds can dissociate within animal metabolism whereas real covalent bonds cannot. Chelated minerals are molecules that have a metal bound to an organic ligand through coordinated bonds; but many organic minerals are not chelates or are not even bound through coordinated bonds. Utilization of organic minerals is largely dependent on the ligand; therefore, amino acids and other small molecules with facilitated access to the enterocyte are supposed to be better utilized by animals. Organic minerals with ligands presenting long chains may require digestion prior to absorption. After absorption, organic minerals may present physiological effects, which improve specific metabolic responses, such as the immune response. Many studies have demonstrated the benefits of metal-amino acid chelates on animal metabolism, but the detection positive effects on live performance is less consistent.

  20. International strategic minerals inventory summary report; niobium (columbium) and tantalum

    Science.gov (United States)

    Crockett, R.N.; Sutphin, D.M.

    1993-01-01

    Major world resources of niobium and tantalum are described in this summary report of information in the International Strategic Minerals Inventory (ISMI). ISMI is a cooperative data-collection effort of earth-science and mineral-resource agencies in Australia, Canada, the Federal Republic of Germany, the Republic of South Africa, the United Kingdom, and the United States of America. Part I of this report presents an overview of the resources and potential supply of niobium and tantalum based on inventory information; Part II contains tables of both geologic and mineral-resource information and includes production data collected by ISMI participants. Niobium is used principally as an alloying element in special steels and superalloys, and tantalum is used mainly in electronics. Minerals in the columbite-tantalite series are principal ore minerals of niobium and tantalum. Pyrochlore is a principal source of niobium. These minerals are found in carbonatite, certain rocks in alkaline igneous complexes, pegmatite, and placer deposits. ISMI estimates show that there are over 7 million metric tons of niobium and almost 0.5 million metric tons of tantalum in known deposits, outside of China and the former Soviet Union, for which reliable estimates have been made. Brazilian deposits, followed by Canadian deposits, contain by far the largest source of niobium. Tantalum production is spread widely among several countries, and Brazil and Canada are the most significant of these producers. Brazil's position is further strengthened by potential byproduct columbite from tin mining. Present economically exploitable resources of niobium appear to be sufficient for the near future, but Brazil will continue to be the predominant world supplier of ferrocolumbium. Tantalum, a byproduct of tin production, has been captive to the fluctuations of that market, but resources in pegmatite in Canada and Australia make it likely that future increases in the present modest demand will be met.

  1. Uraniferous minerals - uraninite and derived or related uraniferous minerals; Mineraux uraniferes - uraninite et mineraux uraniferes derives ou associes

    Energy Technology Data Exchange (ETDEWEB)

    Lebrun, P.; Cesbron, F.; Le Cleac' h, J.M.; Lebocey, J.

    2009-07-01

    This special issue of 'Mineraux et Fossiles' journal (no.28) proposes a real trip in the uranium world with the exception of the industrial and military applications. The book comprises 6 chapters fully illustrated with figures and photos of minerals dealing with: 1 - a brief history of uranium (including radioactivity); 2 - crystallo-chemistry of some uranium minerals; 3 - uranium minerals with a presentation of the most important species ('remarkable' species); 4 - classification of uranium deposits; 5 - most famous uranium deposits which played an important role in the development of nuclear industry (Jachymov deposit in Czech Republic, Shinkolobwe in Katanga, Oklo in Gabon etc); 6 - uranium usages, in particular in glass and ceramics coloring and in geochronology. (J.S.)

  2. Submerged Conidiation and Product Formation by Aspergillus niger at Low Specific Growth Rates Are Affected in Aerial Developmental Mutants

    DEFF Research Database (Denmark)

    Jørgensen, Thomas R.; Nielsen, Kristian Fog; Arentshorst, Mark

    2011-01-01

    Exposure to an aerial environment or severe nutrient limitation induces asexual differentiation in filamentous fungi. Submerged cultivation of Aspergillus niger in carbon- and energy-limited retentostat cultures both induces and fuels conidiation. Physiological and transcriptomic analyses have...

  3. Towards assessing the social sustainability performance of the petroleum industry in the Niger Delta Region of Nigeria

    CSIR Research Space (South Africa)

    Bubou, GM

    2009-05-01

    Full Text Available Unresolved social issues between the local community and the petroleum industry plague the Niger Delta Region of Nigeria. These concerns are addressed by introducing a social sustainability assessment framework for the petroleum industry. Key...

  4. Submerged Conidiation and Product Formation by Aspergillus niger at Low Specific Growth Rates Are Affected in Aerial Developmental Mutants

    NARCIS (Netherlands)

    Jørgensen, T.R.; Nielsen, K.F.; Arentshorst, M.; Park, J.; Van den Hondel, C.A.; Frisvad, J.C.; Ram, A.F.

    2011-01-01

    Exposure to an aerial environment or severe nutrient limitation induces asexual differentiation in filamentous fungi. Submerged cultivation of Aspergillus niger in carbon- and energy-limited retentostat cultures both induces and fuels conidiation. Physiological and transcriptomic analyses have

  5. Submerged Conidiation and Product Formation by Aspergillus niger at Low Specific Growth Rates Are Affected in Aerial Developmental Mutants

    NARCIS (Netherlands)

    Jørgensen, T.R.; Nielsen, K.F.; Arentshorst, M.; Park, J.; Van den Hondel, C.A.; Frisvad, J.C.; Ram, A.F.

    2011-01-01

    Exposure to an aerial environment or severe nutrient limitation induces asexual differentiation in filamentous fungi. Submerged cultivation of Aspergillus niger in carbon- and energy-limited retentostat cultures both induces and fuels conidiation. Physiological and transcriptomic analyses have revea

  6. Remediation of contaminated lands in the Niger Delta, Nigeria: Prospects and challenges.

    Science.gov (United States)

    Zabbey, Nenibarini; Sam, Kabari; Onyebuchi, Adaugo Trinitas

    2017-05-15

    Contamination of the total environment (air, soil, water and biota) by crude oil has become a paramount interest in the Niger Delta region of Nigeria. Studies have revealed variable impacts of oil toxicity on the environment and exposed populations. The revelation gained much international attention in 2011 with the release of Environmental Assessment of Ogoniland report by the United Nations Environment Programme (UNEP). This has up scaled local and international pressures for urgent clean-up and restoration of degraded bio-resource rich environments of the Niger Delta, starting from Ogoniland. Previous remediation attempts in the area had failed due to erroneous operational conclusions (such as conclusions by oil industry operators that the Niger Delta soil is covered by a layer of clay and as such oil percolation remains within the top soil and makes remediation by enhanced natural attenuation (RENA) suitable for the region) and the adoption of incompatible and ineffective approaches (i.e. RENA) for the complex and dynamic environments. Perennial conflicts, poor regulatory oversights and incoherent standards are also challenges. Following UNEP recommendations, the Federal Government of Nigeria recently commissioned the clean-up and remediation of Ogoniland project; it would be novel and trend setting. While UNEP outlined some measures of contaminated land remediation, no specific approach was identified to be most effective for the Niger Delta region. Resolving the technical dilemma and identified social impediments is the key success driver of the above project. In this paper, we reviewed the socio-economic and ecological impacts of contaminated land in the Niger Delta region and the global state-of-the-art remediation approaches. We use coastal environment clean-up case studies to demonstrate the effectiveness of bioremediation (sometimes in combination with other technologies) for remediating most of the polluted sites in the Niger Delta. Bioremediation

  7. Recombinant hepatitis B surface antigen production in Aspergillus niger: evaluating the strategy of gene fusion to native glucoamylase

    CSIR Research Space (South Africa)

    James, ER

    2012-10-01

    Full Text Available Microbiology and Biotechnology October 2012/ Vol. 96, No.2 Recombinant hepatitis B surface antigen production in Aspergillus niger: evaluating the strategy of gene fusion to native glucoamylase ER James a,c & WH van Zyl b & PJ van Zyl c & JF Görgens..., Pretoria 0001, South Africa Abstract This study demonstrates the potential of Aspergillus niger as a candidate expression system for virus- like particle production using gene fusion. Hepatitis B surface antigen (HBsAg) production, targeted...

  8. Lipase production by recombinant strains of Aspergillus niger expressing a lipase-encoding gene from Thermomyces lanuginosus

    DEFF Research Database (Denmark)

    Prathumpai, Wai; Flitter, S.J.; Mcintyre, Mhairi

    2004-01-01

    Two recombinant strains of Aspergillus niger (NW 297-14 and NW297-24) producing a heterologous lipase from Thermomyces lanuginosus were constructed. The heterologous lipase was expressed using the TAKA amylase promoter from Aspergillus oryzae. The production kinetics of the two strains on different...... shows that it is possible to obtain high productivities of heterologous fungal enzymes in A. niger. However, SDS-PAGE analysis showed that most of the produced lipase was bound to the cell wall....

  9. Pharmacopée vétérinaire traditionnelle des éleveurs du sud-Niger

    Directory of Open Access Journals (Sweden)

    Puffet, H.

    1985-01-01

    Full Text Available Traditional veterinary medicine in southern Niger. Investigations have been carried out in Southern Niger (Dosso department to make up an inventory of plants used for local veterinary cures. The results are presented in a report destined for field technical agents. This report displays the results in tables, showing the symptoms and diseases of different species of domestic animals, as well as the remedial plants and their manners of use.

  10. Effect of temperature and water activity on the production of fumonisins by Aspergillus niger and different Fusarium species

    Directory of Open Access Journals (Sweden)

    Frisvad Jens C

    2009-12-01

    Full Text Available Abstract Background Fumonisins are economically important mycotoxins which until recently were considered to originate from only a few Fusarium species. However recently a putative fumonisin gene cluster was discovered in two different Aspergillus niger strains followed by detection of an actual fumonisin B2 (FB2 production in four strains of this biotechnologically important workhorse. Results In the present study, a screening of 5 A. niger strains and 25 assumed fumonisin producing Fusarium strains from 6 species, showed that all 5 A. niger strains produced FB2 and 23 of 25 Fusarium produced fumonisin B1 and other isoforms (fumonisin B2 and B3. Five A. niger and five Fusarium spp. were incubated at six different temperatures from 15-42°C on Czapek Yeast Agar +5% salt or Potato Dextrose Agar. A. niger had the highest production of FB2 at 25-30°C whereas Fusarium spp. had the maximal production of FB1 and FB2 at 20-25°C. Addition of 2.5-5% NaCl, or 10-20% sucrose increased the FB2 production of A. niger, whereas addition of glycerol reduced FB2 production. All three water activity lowering solutes reduced the fumonisin production of the Fusarium species. Conclusion The present study shows that the regulation of fumonisin production is very different in A. niger and Fusarium, and that food and feeds preserved by addition of sugar or salts may be good substrates for fumonisin B2 production by A. niger.

  11. Republic of Ireland: abortion controversy.

    Science.gov (United States)

    1998-01-01

    The problems associated with illegal abortion dominate public discussion in Ireland. While abortion is illegal in Ireland, the Supreme Court directed in 1992 that Irish women can go to Britain for abortions when their lives are thought to be at risk. Abortion was a constant feature during the Irish Presidential election campaign in October, while a dispute about the future of a 13-year-old girl's pregnancy dominated the headlines in November. The presidential election on October 30 resulted in a victory for one of the two openly anti-choice candidates, Mary McAleese, a lawyer from Northern Ireland. With a voter turnout of 47.6%, McAleese polled 45.2% of the votes cast. Although the president may refuse to sign bills which have been passed by parliament, McAleese has said that she will sign whatever bill is placed before her, even if it liberalizes abortion law in the republic. As for the case of the 13-year-old pregnant girl, she was taken into the care of Irish health authority officials once the case was reported to the police. However, the health board, as a state agency, is prevented by Irish law from helping anyone travel abroad for abortion. The girl was eventually given leave in a judgement by a High Court Judicial Review on November 28 to travel to England for an abortion.

  12. Occurrence of 1,1'-dimethyl-4,4'-bipyridinium (Paraquat) in irrigated soil of the Lake Chad Basin, Niger.

    Science.gov (United States)

    Crampon, Marc; Copard, Yoann; Favreau, Guillaume; Raux, Julie; Merlet-Machour, Nadine; Le Coz, Mathieu; Ibrahim, Maïmouna; Peulon-Agasse, Valérie; Portet-Koltalo, Florence

    2014-09-01

    Increased use of agrochemical products to improve yields for irrigated crops in sub-Saharan Africa has been accompanied by a significant increase in the risk of environmental contamination. Detailed examples of the fate of pesticides after initial spreading on crop fields are scarce in tropical regions, where safe practices and related health risks are poorly understood by smallholder farmers. In the semi-arid environment of the Lake Chad Basin, SE Niger, both intrinsic properties of pesticides and extrinsic factors such as soil and climate helped to characterize processes leading to an accumulation of pesticides in soils. Analysis by HPLC-UV of a 6 m deep soil profile showed the presence of Paraquat at concentrations from 953 ± 102 μg kg(-1) to 3083 ± 175 μg kg(-1) at depths between 0.80 and 2.75 m below the land surface. Soil analysis revealed that up to approximately 15 % of the total soil matrix consists of smectites, a clay mineral capable of retaining cationic pesticides such as Paraquat, and a very low content of organic matter (Paraquat could be stored and not bioavailable in a clayey barrier at approximately 2-m depth and therefore does not represent an immediate risk for populations or environment in this form. However, if the Paraquat application rate remains constant, the clayey barrier could reach a saturation limit within 150-200 years and 180-220 years if we consider a DT50 in soil of ~1,000 days (FAO). Consequently, it could lead to a deeper infiltration and so a pollution of groundwater. Such a scenario can represent a health risk for drinking water and for the Lake Chad, which is a major resource for this densely populated region of semi-arid Africa. Further analyses should focus on deeper layers and groundwater Paraquat contents to validate or invalidate the hypothesis of storage in this clay-rich layer.

  13. Systematic assessment of fault stability in the Northern Niger Delta Basin, Nigeria: Implication for hydrocarbon prospects and increased seismicities

    Science.gov (United States)

    Adewole, E. O.; Healy, D.

    2017-03-01

    Accurate information on fault networks, the full stress tensor, and pore fluid pressures are required for quantifying the stability of structure-bound hydrocarbon prospects, carbon dioxide sequestration, and drilling prolific and safe wells, particularly fluid injections wells. Such information also provides essential data for a proper understanding of superinduced seismicities associated with areas of intensive hydrocarbon exploration and solid minerals mining activities. Pressure and stress data constrained from wells and seismic data in the Northern Niger Delta Basin (NNDB), Nigeria, have been analysed in the framework of fault stability indices by varying the maximum horizontal stress direction from 0° to 90°, evaluated at depths of 2 km, 3.5 km and 4 km. We have used fault dips and azimuths interpreted from high resolution 3D seismic data to calculate the predisposition of faults to failures in three faulting regimes (normal, pseudo-strike-slip and pseudo-thrust). The weighty decrease in the fault stability at 3.5 km depth from 1.2 MPa to 0.55 MPa demonstrates a reduction of the fault strength by high magnitude overpressures. Pore fluid pressures > 50 MPa have tendencies to increase the risk of faults to failure in the study area. Statistical analysis of stability indices (SI) indicates faults dipping 50°-60°, 80°-90°, and azimuths ranging 100°-110° are most favourably oriented for failure to take place, and thus likely to favour migrations of fluids given appropriate pressure and stress conditions in the dominant normal faulting regime of the NNDB. A few of the locally assessed stability of faults show varying results across faulting regimes. However, the near similarities of some model-based results in the faulting regimes explain the stability of subsurface structures are greatly influenced by the maximum horizontal stress (SHmax) direction and magnitude of pore fluid pressures.

  14. Superimposing various biophysical and social scales in a rapidly changing rural area (SW Niger)

    Science.gov (United States)

    Leduc, Christian; Massuel, Sylvain; Favreau, Guillaume; Cappelaere, Bernard; Leblanc, Marc; Bachir, Salifou; Ousmane, Boureïma

    2014-05-01

    In SW Niger, close to Niamey, a detailed hydrological survey has been developed for the last 20 years (international experiments HAPEX-SAHEL and later AMMA), investigating the distribution of water in atmosphere, surface, soil and aquifers. It covers an area of about 10 000 km2, with a series of imbricated scales of instrumentation, in time and space. This dense long term field observation led to many major scientific results. Among them, one of the most original and paradoxical is the continuous rise of the water table, even during the severe droughts of the 1970s and 1980s (about 3 m in the last 30 years). In spite of a large apparent homogeneity of the biophysical environment throughout the region, numerous heterogeneities exist at different scales, complicating the hydrological analysis. On the surface, the hydrological system was, ~6000 years ago, a structured drainage network leading to the Niger River. It was later broken into much smaller elements by aeolian dunes deposited during arid episodes and the study area now appears as a juxtaposition of hundreds of small endorheic catchments (most often 1 to 20 km2) where the surface runoff finally ends in temporary ponds. During most violent rainy events, erosion can be locally very severe and modify durably the size of the catchment and the local hydrology. Conversely, during smaller rainy events, surface runoff may never reach the ponds because it infiltrates in more permeable zones at mid-slope. The actual surface area of the catchment contributing to the surface runoff thus varies considerably with time. Because of their great number, only a few catchments are instrumented and extrapolation of measurements to ungauged catchments is an additional difficulty. Most of water temporarily stored in ponds infiltrates and recharges groundwater. The Continental Terminal (CT) aquifer system is made of three independent layers, of which the upper one (CT3) is only considered here. The CT aquifer systems is a

  15. [Characterization of air mycobiota in two repositories of the National Archives of the Republic of Cuba].

    Science.gov (United States)

    Borrego Alonso, Sofía; Perdomo Amistad, Ivette

    2014-01-01

    The high relative humidity and temperatures in tropical countries create favorable conditions for development of fungi that are not only a risk to human health but they can also colonize documentary support. To study the concentration of the airborne fungi in two repositories of the National Archives of the Republic of Cuba, the mycobiota deposited on different photographic supports and maps preserved in these repositories, and to determine the taxonomic characterization of the fungi isolated. The air sampling was performed using a sedimentation method, and the supports (6 pictures and 7 maps) were analyzed using moistened sterile swabs. The Cladosporium genus was predominant, followed by Aspergillus and Penicillium genera. Filamentous fungi were isolated in all the photos and maps, and yeasts were only isolated from a photographic supports and a map. We identified several species of Aspergillus and Penicillium genera, but Aspergillus niger and Aspergillus flavus predominated. Candida and Rhodotorula were the yeast genera isolated. The fungal concentration of the air demonstrated that the environments were not contaminated. From the 26 species of filamentous fungi isolated only 5 were detected in the indoor air of the repositories and on one or more of the document supports analyzed (representing a 19.3%). This shows that there is a low ecological relationship between the fungi detected in the indoor air and those that were isolated from the supports studied. Copyright © 2012 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  16. 果胶酶高产菌Aspergillus niger HYA4的选育%Breeding of high yield strain Aspergillus nigerHYA4 for pectinase

    Institute of Scientific and Technical Information of China (English)

    田英华; 刘晓兰; 邓永平

    2005-01-01

    采用紫外线处理黑曲霉(Aspergillus niger)HY4孢子,照射剂量为75s.获得一株高产果胶酶突变株HYA4,在优化的固体发酵条件下酶活力达1285U/g物料,比出发菌株提高了2倍,为亚麻脱胶酶的生产提供了良好的菌株.

  17. 43 CFR 19.8 - Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

    Science.gov (United States)

    2010-10-01

    ... patents, and mineral leasing within National Forest Wilderness. 19.8 Section 19.8 Public Lands: Interior... § 19.8 Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest... locations, mineral patents, and mineral leasing within National Forest Wilderness are contained in parts...

  18. Genomic analysis of the aconidial and high-performance protein producer, industrially relevant Aspergillus niger SH2 strain.

    Science.gov (United States)

    Yin, Chao; Wang, Bin; He, Pan; Lin, Ying; Pan, Li

    2014-05-15

    Aspergillus niger is usually regarded as a beneficial species widely used in biotechnological industry. Obtaining the genome sequence of the widely used aconidial A. niger SH2 strain is of great importance to understand its unusual production capability. In this study we assembled a high-quality genome sequence of A. niger SH2 with approximately 11,517 ORFs. Relatively high proportion of genes enriched for protein expression related FunCat items verify its efficient capacity in protein production. Furthermore, genome-wide comparative analysis between A. niger SH2 and CBS513.88 reveals insights into unique properties of A. niger SH2. A. niger SH2 lacks the gene related with the initiation of asexual sporulation (PrpA), leading to its distinct aconidial phenotype. Frame shift mutations and non-synonymous SNPs in genes of cell wall integrity signaling, β-1,3-glucan synthesis and chitin synthesis influence its cell wall development which is important for its hyphal fragmentation during industrial high-efficiency protein production.

  19. Race and nation in the Dominican Republic

    Directory of Open Access Journals (Sweden)

    Michiel Baud

    2002-07-01

    Full Text Available [First paragraph] Coloring the Nation: Race and Ethnicity in the Dominican Republic. DAVID HOWARD. Oxford: Signal; Boulder: Lynne Rienner, 2001. x + 227 pp. (Paper US$ 19.95 Race and Politics in the Dominican Republic. ERNESTO SAGAS. Gainesville: University Press of Florida, 2000. xii + 161 pp. (Cloth US$ 49.95, Paper US$ 24.95 Peasants and Religion: A Socioeconomic Study of Dios Olivorio and the Palma Sola Movement in the Dominican Republic. JAN LUNDIUS & MATS LUNDAHL. London: Routledge, 2000. xxvi + 774 pp. (Cloth US$ 135.00 The social and political relations between the Dominican Republic and Haiti, and especially their racial and ethnic contents, are extremely difficult to approach in an even- handed and unbiased way. Much ink has been spilled over the conflictive relations between these two countries, and on race relations in the Dominican Republic. Much of what has been said must be considered unfounded or biased, not to mention sensationalist. The books under review try to pro vide new insights into the issue and at the same time to steer clear of these problems.

  20. Secretome data from Trichoderma reesei and Aspergillus niger cultivated in submerged and sequential fermentation methods

    Directory of Open Access Journals (Sweden)

    Camila Florencio

    2016-09-01

    Full Text Available The cultivation procedure and the fungal strain applied for enzyme production may influence levels and profile of the proteins produced. The proteomic analysis data presented here provide critical information to compare proteins secreted by Trichoderma reesei and Aspergillus niger when cultivated through submerged and sequential fermentation processes, using steam-explosion sugarcane bagasse as inducer for enzyme production. The proteins were organized according to the families described in CAZy database as cellulases, hemicellulases, proteases/peptidases, cell-wall-protein, lipases, others (catalase, esterase, etc., glycoside hydrolases families, predicted and hypothetical proteins. Further detailed analysis of this data is provided in “Secretome analysis of Trichoderma reesei and Aspergillus niger cultivated by submerged and sequential fermentation process: enzyme production for sugarcane bagasse hydrolysis” C. Florencio, F.M. Cunha, A.C Badino, C.S. Farinas, E. Ximenes, M.R. Ladisch (2016 [1].

  1. Morphological transitions under oxidative stress in response to metabolite formation in Aspergillus niger.

    Science.gov (United States)

    Lv, Yangyong; Zhou, Feng; Wang, Bin; Pan, Li

    2015-03-01

    Oxidative stress is associated with metabolite formation in fungi. In contrast to an Aspergillus niger wild-type strain, a sclerotia-formation regulator ansclR deletion strain demonstrated increased susceptibility to oxidative stress and reduced transcription of the catalase gene, catB, while an ansclR overexpression strain showed enhanced resistance to oxidative stress and increased expression of catB. In addition, ansclR complementation strain expressed a wild-type level of catB. The ansclR overexpression strain also produced the same metabolites as the wild type strain treated with H2O2. Furthermore, LC-MS, NMR, and IR analyses showed that the main metabolite was a steroid analog. Our study adds new clues to oxidative stress-related factors and metabolite formation in A. niger.

  2. Efficient Conversion of Inulin to Inulooligosaccharides through Endoinulinase from Aspergillus niger.

    Science.gov (United States)

    Xu, Yanbing; Zheng, Zhaojuan; Xu, Qianqian; Yong, Qiang; Ouyang, Jia

    2016-03-30

    Inulooligosaccharides (IOS) represent an important class of oligosaccharides at industrial scale. An efficient conversion of inulin to IOS through endoinulinase from Aspergillus niger is presented. A 1482 bp codon optimized gene fragment encoding endoinulinase from A. niger DSM 2466 was cloned into pPIC9K vector and was transformed into Pichia pastoris KM71. Maximum activity of the recombinant endoinulinase, 858 U/mL, was obtained at 120 h of the high cell density fermentation process. The optimal conditions for inulin hydrolysis using the recombinant endoinulinase were investigated. IOS were harvested with a high concentration of 365.1 g/L and high yield up to 91.3%. IOS with different degrees of polymerization (DP, mainly DP 3-6) were distributed in the final reaction products.

  3. Biotransformation of the streptomyces scabies phytotoxin thaxtomin A by the fungus aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Lazarovits, G.; Hill, J. [Agriculture and Agri-Food Canada, Southern Crop Protection and Food Research Centre, London, Ontario (Canada)]. E-mail: Lazarovitsg@agr.gc.ca; King, R. [Agriculture and Agri-Food Canada, Potato Research Centre, Fredericton, New Brunswick (Canada); Calhoun, L.A. [Univ. of New Brunswick, Dept. of Chemistry, Fredericton, New Brunswick (Canada)

    2004-07-01

    Of several hundred microorganisms randomly selected from the environment, only a fungal isolate identified as Aspergillus niger van Tiegham var. niger was found to transform the phytotoxin thaxtomin A to much less toxic metabolites. The rate and extent of transformation of thaxtomin A was tested under a variety of conditions, including different growth media, biomass concentrations, incubation periods, and shaker speeds. Under optimum conditions the fungus converted thaxtomin A into two major and five minor metabolites. The two major metabolites and three of the five minor metabolites were fully characterized by a combination of mass spectral and nuclear magnetic resonance techniques. When assayed on aseptically produced mini-tubers, the major metabolites proved to be much less phytotoxic than thaxtomin A. (author)

  4. The promoter of the glucoamylase-encoding gene of Aspergillus niger functions in Ustilago maydis

    Energy Technology Data Exchange (ETDEWEB)

    Smith, T.L. (Dept. of Agriculture, Madison, WI (United States) Univ. of Wisconsin, Madison (United States)); Gaskell, J.; Cullen, D. (Dept. of Agriculture, Madison, WI (United States)); Berka, R.M.; Yang, M.; Henner, D.J. (Genentech Inc., San Francisco, CA (United States))

    1990-01-01

    Promoter sequences from the Aspergillus niger glucoamylase-encoding gene (glaA) were linked to the bacterial hygromycin (Hy) phosphotransferase-encoding gene (hph) and this chimeric marker was used to select Hy-resistant (Hy[sup R]) Ustilago maydis transformants. This is an example of an Ascomycete promoter functioning in a Basidiomycete. Hy[sup R] transformants varied with respect to copy number of integrated vector, mitotic stability, and tolerance to Hy. Only 216 bp of glaA promoter sequence is required for expression in U. maydis but this promoter is not induced by starch as it is in Aspergillus spp. The transcription start points are the same in U. maydis and A. niger.

  5. Factors Influencing Household Food Security in West Africa: The Case of Southern Niger

    Directory of Open Access Journals (Sweden)

    Seydou Zakari

    2014-03-01

    Full Text Available Food insecurity is a major challenge for Niger and for many African countries. The purpose of this study is to investigate the factors affecting household food security in Niger. Based on survey data covering 500 households, drought, high food prices, poverty, soil infertility, disease and insect attacks are reported by the respondents to be the main causes of food insecurity. The empirical results from logistic regression revealed that the gender of the head of household, diseases and pests, labor supply, flooding, poverty, access to market, the distance away from the main road and food aid are significant factors influencing the odds ratio of a household having enough daily rations. Another important finding is that female headed households are more vulnerable to food insecurity compared to male headed households. The findings of this study provide evidence that food insecurity continues to affect the Nigerien population.

  6. SECONDARY METABOLITE FROM ENDOPHYTIC FUNGI Aspergillus niger OF THE STEM BARK OF KANDIS GAJAH (Garcinia griffithii

    Directory of Open Access Journals (Sweden)

    Elfita Elfita

    2012-06-01

    Full Text Available Garcinia griffithii are known as kandis gajah including the Garcinia genus. This plant has been traditionally used by local communities Sarasah Bonta, Lembah Arau, West Sumatra, to treat various diseases including gout. Aspergillus niger was isolated from the tissues of the stem bark of Garcinia griffithii. The fungi strain was identified base on colony and cell morphology characteristic. Aspergillus niger cultured in media 5L Potatos Dextose Broth (PDB for 8 weeks and filtered. Media that already contains secondary metabolites are partitioned using ethyl acetate solvent in 5 L (twice, followed by evaporation. Furthermore, the extract is separated by chromatographic techniques to obtain a pure compound of white crystal. The molecular structures of isolated compounds are determined by spectroscopic methods including IR, 1H-NMR, 13C-NMR, HMQC, HMBC, and COSY. The compound was determined as phenolic (1.

  7. Soil Dust Aerosols and Wind as Predictors of Seasonal Meningitis Incidence in Niger

    Science.gov (United States)

    Perez Garcia Pando, Carlos; Stanton, Michelle C.; Diggle, Peter J.; Trzaska, Sylwia; Miller, Ron L.; Perlwitz, Jan P.; Baldasano, Jose M.; Cuevas, Emilio; Ceccato, Pietro; Yaka, Pascal; Thomson, Madeleine C.

    2014-01-01

    Background: Epidemics of meningococcal meningitis are concentrated in sub-Saharan Africa during the dry season, a period when the region is affected by the Harmattan, a dry and dusty northeasterly trade wind blowing from the Sahara into the Gulf of Guinea.Objectives: We examined the potential of climate-based statistical forecasting models to predict seasonal incidence of meningitis in Niger at both the national and district levels.Data and methods: We used time series of meningitis incidence from 1986 through 2006 for 38 districts in Niger. We tested models based on data that would be readily available in an operational framework, such as climate and dust, population, and the incidence of early cases before the onset of the meningitis season in January-May. Incidence was used as a proxy for immunological state.

  8. Long term precipitation chemistry and wet deposition in a remote dry savanna site in Africa (Niger

    Directory of Open Access Journals (Sweden)

    C. Galy-Lacaux

    2008-03-01

    Full Text Available A long-term measurement of precipitation chemistry has been carried-out in a rural area of Banizoumbou, in the Sahel (Niger, representative of the african semi-arid savanna ecosystem. A total of 305 rainfall samples, representing 90% of the total annual rainfall, were collected with an automatic wet-only rain sampler from June 1994 to September 2005. Using ionic chromatography, pH major inorganic and organic ions were analyzed. Rainwater chemistry at the site is controlled by soil dust emissions associated to a strong terrigeneous contribution represented by SO42–, Ca2+, Carbonates, K+ and Mg2+. Calcium and carbonates represent about 40% of the total ionic charge of precipitation. The second highest contribution is nitrogenous, with annual Volume Weighed Mean (VWM NO3 and NH4+, concentrations of 11.6 and 18.1 μeq.l−1, respectively. This is thesignature of ammonia sources related to animals and NOx emissions from savannas soils rain-induced, at the beginning of the rainy season. The mean annual NH3 and NO2 air concentration are of 6 ppbv and 2.6 ppbv, respectively. The annual VWM precipitation concentration of sodium and chloride are both of 8.7 μeq.l−1 and reflects the marine signature from the monsoon humid air masses coming from the ocean. The mean pH value, calculated from the VWM of H+, is 5.64. Acidity is neutralized by mineral dust, mainly carbonates, and/or dissolved gases such NH3. High level of organic acidity with 8 μeq.l−1 and 5.2 μeq.l−1 of formate and acetate were found, respectively. The analysis of monthly Black Carbon emissions and FAPAR values show that both biogenic emission from vegetation and biomass burning sources could explain the organic acidity content of the precipitation. The interannual variability of the

  9. Long term precipitation chemistry and wet deposition in a remote dry savanna site in Africa (Niger

    Directory of Open Access Journals (Sweden)

    C. Galy-Lacaux

    2009-03-01

    Full Text Available Long-term precipitation chemistry have been recorded in the rural area of Banizoumbou (Niger, representative of a semi-arid savanna ecosystem. A total of 305 rainfall samples ~90% of the total annual rainfall were collected from June 1994 to September 2005. From ionic chromatography, pH major inorganic and organic ions were detected. Rainwater chemistry is controlled by soil/dust emissions associated with terrigeneous elements represented by SO42−, Ca2+, Carbonates, K+ and Mg2+. It is found that calcium and carbonates represent ~40% of the total ionic charge. The second highest contribution is nitrogenous, with annual Volume Weighed Mean (VWM for NO3 and NH4+ concentrations of 11.6 and 18.1 μeq.l−1, respectively. This is the signature of ammonia sources from animals and NOx emissions from savannas soil-particles rain-induced. The mean annual NH3 and NO2 air concentration are of 6 ppbv and 2.6 ppbv, respectively. The annual VWM precipitation concentration of sodium and chloride are both of 8.7 μeq.l−1 which reflects the marine signature of monsoonal and humid air masses. The median pH value is of 6.05. Acidity is neutralized by mineral dust, mainly carbonates, and/or dissolved gases such NH3. High level of organic acidity with 8μeq.l−1 and 5.2 μeq.l−1 of formate and acetate were also found. The analysis of monthly Black Carbon emissions and Fraction of Absorbed Photosynthetically Active Radiation (FAPAR values show that both biogenic emission from vegetation and biomass burning could explain the rainfall organic acidity content. The interannual variability of the VWM concentrations around the mean (1994–2005 is between ±5% and ±30% and mainly due to variations of sources strength and rainfall spatio-temporal distribution. From 1994 to 2005

  10. In vitro androgenetic cultures of Hyoscyamus niger L., H. albus L. and alkaloid content assay

    Directory of Open Access Journals (Sweden)

    Maria Wesołwska

    2014-01-01

    Full Text Available In vitro cultures of Hyoscyamus niger L. and H. albus L. anthers were initiated which resulted in obtaining androgenectic plants and callus cultures. The leaves of these pants and the callus cultures were subjected to analysis (TLC, GC for the presence of alkaloids, derivatives of tropane. In the studied material, alkaloids of different qualitative and quantitative composition from that of ground-grown plants were found.

  11. Disparity in Democracies: A Comparative Case Study of Mali and Niger

    Science.gov (United States)

    2010-12-01

    ANDP Alliance Nigeriennepour la Democratie et le Progres APDF Association pour le Progres et la Defense des Droits de Femme Maliennes ARD Alliance...democratic consolidation was negatively impacted during this period. Among other problems, Freedom House’s critique of Niger’s drop in PR was... Droits de la Femme and more liberal Islamic associations, such as Islamic Action, an association of Muslim intellectuals. The debate over excision

  12. Genome mining and functional genomics for siderophore production in Aspergillus niger.

    Science.gov (United States)

    Franken, Angelique C W; Lechner, Beatrix E; Werner, Ernst R; Haas, Hubertus; Lokman, B Christien; Ram, Arthur F J; van den Hondel, Cees A M J J; de Weert, Sandra; Punt, Peter J

    2014-11-01

    Iron is an essential metal for many organisms, but the biologically relevant form of iron is scarce because of rapid oxidation resulting in low solubility. Simultaneously, excessive accumulation of iron is toxic. Consequently, iron uptake is a highly controlled process. In most fungal species, siderophores play a central role in iron handling. Siderophores are small iron-specific chelators that can be secreted to scavenge environmental iron or bind intracellular iron with high affinity. A second high-affinity iron uptake mechanism is reductive iron assimilation (RIA). As shown in Aspergillus fumigatus and Aspergillus nidulans, synthesis of siderophores in Aspergilli is predominantly under control of the transcription factors SreA and HapX, which are connected by a negative transcriptional feedback loop. Abolishing this fine-tuned regulation corroborates iron homeostasis, including heme biosynthesis, which could be biotechnologically of interest, e.g. the heterologous production of heme-dependent peroxidases. Aspergillus niger genome inspection identified orthologues of several genes relevant for RIA and siderophore metabolism, as well as sreA and hapX. Interestingly, genes related to synthesis of the common fungal extracellular siderophore triacetylfusarinine C were absent. Reverse-phase high-performance liquid chromatography (HPLC) confirmed the absence of triacetylfusarinine C, and demonstrated that the major secreted siderophores of A. niger are coprogen B and ferrichrome, which is also the dominant intracellular siderophore. In A. niger wild type grown under iron-replete conditions, the expression of genes involved in coprogen biosynthesis and RIA was low in the exponential growth phase but significantly induced during ascospore germination. Deletion of sreA in A. niger resulted in elevated iron uptake and increased cellular ferrichrome accumulation. Increased sensitivity toward phleomycin and high iron concentration reflected the toxic effects of excessive

  13. Time is of the essence: exploring a measles outbreak response vaccination in Niamey, Niger

    OpenAIRE

    Grais, Rebecca F; Conlan, A.J.K.; Ferrari, M. J.; Djibo, A.; Le Menach, A; O.N. Bjørnstad; Grenfell, B. T.

    2007-01-01

    The current World Health Organization recommendations for response during measles epidemics focus on case management rather than outbreak response vaccination (ORV) campaigns, which may occur too late to impact morbidity and mortality and have a high cost per case prevented. Here, we explore the potential impact of an ORV campaign conducted during the 2003–2004 measles epidemic in Niamey, Niger. We measured the impact of this intervention and also the potential impact of alternative strategie...

  14. Aspergillus niger biofilms for celulasas production: some structural and physiological aspects

    OpenAIRE

    Villena, Gretty K.; Marcel Gutiérrez-Correa

    2013-01-01

    Aspergillus niger biofilms developed on polyester cloth were evaluated considering two aspects related to the growth on surfaces: structure and physiological behavior focused on cellulase production. The biofilm structure was assessed by using electron scanning microphotographs from inoculation and adsorption to 120 h growth. The microphotographs show that biofilm formation can be divided into three phases: 1) Adhesion, which is strongly increased by Aspergillus spore hydrophobicity; 2) Initi...

  15. Aspergillus niger β-galactosidase production by yeast in a continuous high cell density reactor

    OpenAIRE

    2005-01-01

    The continuous production of extracellular heterologous beta-galactosidase by a recombinant flocculating Saccharomyces cerevisiae, expressing the lacA gene (coding for beta-galactosidase) of Aspergillus niger was investigated. A continuous operation was run in a 6.51 airlift bioreactor with a concentric draft tube using lactose as substrate. Data on the operation with semi-synthetic medium with 50 and 100 g/l initial lactose concentrations are presented. The best result for beta-galactosidase...

  16. Les Associations Pastorales et la Gestion des Ressources Naturelles : Tome 2: Niger

    NARCIS (Netherlands)

    H.A. Sidikou (Hamidou)

    1994-01-01

    textabstractLes politiques de développement pastoral en Afrique sahélienne et plus particulièrement au Niger , ont beaucoup évolué au cours des vingt dernières années. Elles ont également montré leurs limites et influencé sinon infléchi de ce fait la perception des organes de développeme

  17. Synthesis of gold nanoparticles by the fungus Aspergillus niger and its efficacy against mosquito larvae

    OpenAIRE

    Prakash, Soam; Namita Soni,Namiata

    2012-01-01

    Namita Soni, Soam PrakashEnvironmental and Advanced Parasitology and Vector Control Biotechnology Laboratories, Department of Zoology, Faculty of Science, Dayalbagh Educational Institute, Dayalbagh, Agra, IndiaBackground: The fungus Aspergillus niger has been selected for the synthesis of gold nanoparticles (AuNPs). The authors report the role of fungi in the synthesis of AuNPs. Additionally, the larvicidal efficacy of these AuNPs was tested using the larvae of three mosquito species: Anophel...

  18. Morphology engineering - Osmolality and its effect on Aspergillus niger morphology and productivity

    Directory of Open Access Journals (Sweden)

    Krull Rainer

    2011-07-01

    Full Text Available Abstract Background The filamentous fungus Aspergillus niger is a widely used strain in a broad range of industrial processes from food to pharmaceutical industry. One of the most intriguing and often uncontrollable characteristics of this filamentous organism is its complex morphology, ranging from dense spherical pellets to viscous mycelia depending on culture conditions. Optimal productivity correlates strongly with a specific morphological form, thus making high demands on process control. Results In about 50 2L stirred tank cultivations the influence of osmolality on A. niger morphology and productivity was investigated. The specific productivity of fructofuranosidase producing strain A. niger SKAn 1015 could be increased notably from 0.5 to 9 U mg-1 h-1 around eighteen fold, by increasing the culture broth osmolality by addition of sodium chloride. The specific productivity of glucoamylase producing strain A. niger AB1.13, could be elevated using the same procedure. An optimal producing osmolality was shown to exist well over the standard osmolality at about 3.2 osmol kg-1 depending on the strain. Fungal morphology of all cultivations was examined by microscope and characterized by digital image analysis. Particle shape parameters were combined to a dimensionless Morphology number, which enabled a comprehensive characterization of fungal morphology correlating closely with productivity. A novel method for determination of germination time in submerged cultivations by laser diffraction, introduced in this study, revealed a decelerated germination process with increasing osmolality. Conclusions Through the introduction of the versatile Morphology number, this study provides the means for a desirable characterization of fungal morphology and demonstrates its relation to productivity. Furthermore, osmolality as a fairly new parameter in process engineering is introduced and found to affect fungal morphology and productivity. Osmolality might

  19. Aspergillus niger peritonitis in a patient on continuous ambulatory peritoneal dialysis

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    Usha Kalawat

    2013-07-01

    Full Text Available Fungal peritonitis is an uncommon condition which is associated with high morbidity and mortality in patients on continuous ambulatory peritoneal dialysis (CAPD. It is associated with several complications and many of the patients who develop this condition are unable to resume CAPD treatment and have to shift to haemodialysis. Here we report the rare occurrence of fungal peritonitis due to Aspergillus niger in a patient on CAPD.

  20. Implicações do fungo Aspergillus niger var. niger sobre o crescimento de isolados de Aspergillus da seção Circumdati e produção de Ocratoxina a Implications of Aspergillus niger var. niger's mold, fungi upon growing Aspergillus's isolate of section Circumdati and Ochratoxin a

    Directory of Open Access Journals (Sweden)

    Patrícia Prado Nasser

    2003-10-01

    Full Text Available Buscando esclarecimento a respeito da inibição ou estímulo na produção de ocratoxina A (OTA e no crescimento dos fungos ocratoxigênicos por fungos que também ocorrem naturalmente associados aos grãos de café, com o presente estudo avaliou-se o efeito inibitório do fungo Aspergillus niger var. niger EcoCentro 1181-01(“inibidor” e seu filtrado, sobre o crescimento de isolados de Aspergillus da seção Circumdati e produção de ocratoxina A. O isolado atoxigênico do fungo “inibidor”, selecionado como possível antagonista para espécies toxigênicas do gênero Aspergillus da seção Circumdati, apresentou um efeito positivo inibidor sobre os índices de velocidade de crescimento micelial em relação aos demais isolados testados. A ação antagonista do fungo “inibidor” associado a grãos de café pode ser um dos fatores responsáveis pelos níveis reduzidos de OTA detectados nas amostras analisadas.The present study evaluated the inhibitory effect of the fungus Aspergillus niger var. niger EcoCentro 1181T-01 (inhibitor and its filtrate on the growth of an Aspergillus isolate of the section Circumdati and ochratoxin A (OTA production. An atoxigenic isolate of the inhibitor fungus screened as possible antagonist for toxigenic species of the genus Aspergillus, section Circumdati,showed a positive inhibitory effect upon mycelial growth velocity indices comparing with the isolates tested. The antagonistic action of the inhibitor fungus associated with coffee beans may be one of the factors responsible for the reduced levels of OTA detected in the samples analyzed.

  1. Transcriptional regulation of the glucoamylase-encoding gene under endoplasmic reticulum stress in Aspergillus niger

    OpenAIRE

    Al-Sheikh, Hashem M.

    2005-01-01

    The ability of many filamentous fungi, such as Aspergillus niger, to secret a high level of homologous proteins has led to their consideration as hosts for the production of heterologous proteins. However, the levels of some secreted heterologous proteins have often been low. Although many strategies have been developed to improve the level of secreted heterologous proteins, further studies into the remaining bottlenecks are required. One common strategy used to improve secreted protein produ...

  2. Growth Kinetics and Production of Glucose Oxidase Using Aspergillus niger NRRL 326

    OpenAIRE

    Gera, N.; Uppaluri, R. V. S.; Sen, S.; Venkata Dasu, V.

    2008-01-01

    In this paper, we demonstrate the substrate inhibition phenomena for growth kinetics of Aspergillus niger NRRL 326 grown on sucrose during glucose oxidase production. The initial set of experiments were carried out using three different substrates, viz., glucose, sucrose and raffinose of which it was observed that sucrose serves better for higher production of glucose oxidase. Experiments involving sensitivity studies conveyed that substrate inhibition became predominant when sucrose mass con...

  3. Fermentasi Tepung Ganyong (Canna edulis Ker.) untuk Produksi Etanol oleh Aspergillus niger dan Zymomonas mobilis

    OpenAIRE

    RATNA SETYANINGSIH; ARI SUSILOWATI; SUSANTI ENI PURWANTARI

    2004-01-01

    The aims of this research were to know the concentration of arrowroot flour which produced the highest reducing sugar in saccharification process by A. niger, as well as to know the efficiency of ethanol production by Z. mobilis. The framework of this research was the increasing needs of ethanol; meanwhile ethanol could be obtained from the fermentation arrowroot. This research was carried out in two stages. In the saccharification stage, there are four concentra...

  4. Cytosolic streaming in vegetative mycelium and aerial structures of Aspergillus niger.

    Science.gov (United States)

    Bleichrodt, R; Vinck, A; Krijgsheld, P; van Leeuwen, M R; Dijksterhuis, J; Wösten, H A B

    2013-03-15

    Aspergillus niger forms aerial hyphae and conidiophores after a period of vegetative growth. The hyphae within the mycelium of A. niger are divided by septa. The central pore in these septa allows for cytoplasmic streaming. Here, we studied inter- and intra-compartmental streaming of the reporter protein GFP in A. niger. Expression of the gene encoding nuclear targeted GFP from the gpdA or glaA promoter resulted in strong fluorescence of nuclei within the vegetative hyphae and weak fluorescence in nuclei within the aerial structures. These data and nuclear run on experiments showed that gpdA and glaA are higher expressed in the vegetative mycelium when compared to aerial hyphae, conidiophores and conidia. Notably, gpdA or glaA driven expression of the gene encoding cytosolic GFP resulted in strongly fluorescent vegetative hyphae and aerial structures. Apparently, GFP streams from vegetative hyphae into aerial structures. This was confirmed by monitoring fluorescence of photo-activatable GFP (PA-GFP). In contrast, PA-GFP did not stream from aerial structures to vegetative hyphae. Streaming of PA-GFP within vegetative hyphae or within aerial structures of A. niger occurred at a rate of 10-15 μm s(-1). Taken together, these results not only show that GFP streams from the vegetative mycelium to aerial structures but it also indicates that its encoding RNA is not streaming. Absence of RNA streaming would explain why distinct RNA profiles were found in aerial structures and the vegetative mycelium by nuclear run on analysis and micro-array analysis.

  5. The Isolation and Characterization of Glucoamylase Enzyme of an Aspergillus niger Natural Isolate

    OpenAIRE

    CORAL, Gökhan

    2014-01-01

    An extracellular glucoamylase enzyme was isolated from Aspergillus niger Z10 natural isolate in a liquid Czapek Dox medium which contained soluble starch (2%) as the sole carbon source. The molecular weight of the enzyme was found to be about 100.000 Daltons through Starch-SDS Polyacrylamide Gel Electrophoresis. The optimal pH range of the enzyme was found to be 4.5-5.5 and it was determined that the thermal stability of this enzyme is quite high.

  6. The Isolation and Characterization of Glucoamylase Enzyme of an Aspergillus niger Natural Isolate

    OpenAIRE

    CORAL, Gökhan

    2000-01-01

    An extracellular glucoamylase enzyme was isolated from Aspergillus niger Z10 natural isolate in a liquid Czapek Dox medium which contained soluble starch (2%) as the sole carbon source. The molecular weight of the enzyme was found to be about 100.000 Daltons through Starch-SDS Polyacrylamide Gel Electrophoresis. The optimal pH range of the enzyme was found to be 4.5-5.5 and it was determined that the thermal stability of this enzyme is quite high.

  7. Exploiting proteomic data for genome annotation and gene model validation in Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Grigoriev Igor V

    2009-02-01

    Full Text Available Abstract Background Proteomic data is a potentially rich, but arguably unexploited, data source for genome annotation. Peptide identifications from tandem mass spectrometry provide prima facie evidence for gene predictions and can discriminate over a set of candidate gene models. Here we apply this to the recently sequenced Aspergillus niger fungal genome from the Joint Genome Institutes (JGI and another predicted protein set from another A.niger sequence. Tandem mass spectra (MS/MS were acquired from 1d gel electrophoresis bands and searched against all available gene models using Average Peptide Scoring (APS and reverse database searching to produce confident identifications at an acceptable false discovery rate (FDR. Results 405 identified peptide sequences were mapped to 214 different A.niger genomic loci to which 4093 predicted gene models clustered, 2872 of which contained the mapped peptides. Interestingly, 13 (6% of these loci either had no preferred predicted gene model or the genome annotators' chosen "best" model for that genomic locus was not found to be the most parsimonious match to the identified peptides. The peptides identified also boosted confidence in predicted gene structures spanning 54 introns from different gene models. Conclusion This work highlights the potential of integrating experimental proteomics data into genomic annotation pipelines much as expressed sequence tag (EST data has been. A comparison of the published genome from another strain of A.niger sequenced by DSM showed that a number of the gene models or proteins with proteomics evidence did not occur in both genomes, further highlighting the utility of the method.

  8. Regulation of the alpha-glucuronidase-encoding gene ( aguA) from Aspergillus niger.

    Science.gov (United States)

    de Vries, R P; van de Vondervoort, P J I; Hendriks, L; van de Belt, M; Visser, J

    2002-09-01

    The alpha-glucuronidase gene aguA from Aspergillus niger was cloned and characterised. Analysis of the promoter region of aguA revealed the presence of four putative binding sites for the major carbon catabolite repressor protein CREA and one putative binding site for the transcriptional activator XLNR. In addition, a sequence motif was detected which differed only in the last nucleotide from the XLNR consensus site. A construct in which part of the aguA coding region was deleted still resulted in production of a stable mRNA upon transformation of A. niger. The putative XLNR binding sites and two of the putative CREA binding sites were mutated individually in this construct and the effects on expression were examined in A. niger transformants. Northern analysis of the transformants revealed that the consensus XLNR site is not actually functional in the aguA promoter, whereas the sequence that diverges from the consensus at a single position is functional. This indicates that XLNR is also able to bind to the sequence GGCTAG, and the XLNR binding site consensus should therefore be changed to GGCTAR. Both CREA sites are functional, indicating that CREA has a strong influence on aguA expression. A detailed expression analysis of aguA in four genetic backgrounds revealed a second regulatory system involved in activation of aguA gene expression. This system responds to the presence of glucuronic and galacturonic acids, and is not dependent on XLNR.

  9. Antifungal mechanism of antibacterial peptide, ABP-CM4, from Bombyx mori against Aspergillus niger.

    Science.gov (United States)

    Zhang, Jie; Wu, Xi; Zhang, Shuang-Quan

    2008-12-01

    Antibacterial peptide, CM4 (ABP-CM4), a 35 amino acid peptide from Chinese silkworm-Bombyx mori, displayed a strong antifungal activity against Aspergillus niger, Trichoderma viride and Gibberella saubinetii. Scanning electron microcopy showed that the morphology of conidia became more irregular and swelled when treated with ABP-CM4 at its minimal inhibitory concentration (MIC) of 8 muM. A cell wall regeneration assay indicated that the plasma membrane was the prime target of ABP-CM4 action. Confocal laser scanning microscopy showed that the cytoskeleton of A. niger was destroyed when treated with ABP-CM4 at 8 muM. Furthermore, transmission electron microscopy showed that the membrane and the cellular organelles of fungus were disrupted and there were many vacuoles in the fungal cellular space after the treatment with ABP-CM4. A gel-retardation assay showed that ABP-CM4 bound the DNA of A. niger. Our results suggest that ABP-CM4 exerts its antifungal activity by disrupting the structure of cell membranes and the cytoskeleton and interacts with the organelles, such as the mitochondrion and with the DNA in the fungal cell, subsequently resulting in cell death.

  10. Niger's Delta vulnerability to river floods due to sea level rise

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    Z. N. Musa

    2014-08-01

    Full Text Available An evaluation of vulnerability to sea level rise is undertaken for the Niger delta based on 17 physical, social and human influence indicators of exposure, susceptibility and resilience. The assessment used GIS techniques to evaluate and analyse the indicators and the index of coastal vulnerability to floods, if sea level rise conditions are occurring. Each indicator value is based on data extracted from various sources including remote sensing, measured historical data series and literature search. Further indicators are ranked on a scale from 1 to 5 representing "very low" to "very high" vulnerability, based on their values. These ranks are used to determine a similar rank for the defined coastal vulnerability index (CVSLRI. Results indicate that 42.2% of the Niger delta is highly vulnerable to sea level rise; such areas been characterized by low slopes, low topography, high mean wave heights, and unconfined aquifers. Moreover the analysis of social and human influences on the environment indicate high vulnerability to sea level rise due to its ranking for type of aquifer, aquifer hydraulic conductivity, population growth, sediment supply and groundwater consumption. Such results may help decision makers during planning, to take proper adaptive measures for reducing Niger Delta's vulnerability, as well as increasing the resilience to potential future floods.

  11. Degradation of chlorimuron-ethyl by Aspergillus niger isolated from agricultural soil.

    Science.gov (United States)

    Sharma, Seema; Banerjee, Kaushik; Choudhury, Partha P

    2012-12-01

    Chlorimuron-ethyl, ethyl-2-[[[[(4-methoxy-6-chloro-pyrimidin-2-yl)amino]carbonyl]amino] sulfonyl]benzoate, is used as a pre- and postemergence herbicide for the control of important broadleaved weeds in soybean and maize. Due to its phytotoxicity to rotation crops, concerns regarding chlorimuron contamination of soil and water have been raised. Although it is degraded in the agricultural environment primarily via pH- and temperature-dependent chemical hydrolysis, microbial transformation also has an important role. Fungi such as Fusarium and Alternaria are unable to survive in artificial media containing chlorimuron-ethyl at 25 mg L(-1) . However, Aspergillus niger survived in minimal broth containing chlorimuron at 2 mg mL(-1) . Aspergillus niger degraded the herbicide to harvest energy through two major routes of degradation. One route involves the cleavage of the sulfonylurea bridge, resulting in the formation of two major metabolites, namely ethyl-2-aminosulfonylbenzoate (I) and 4-methoxy-6-chloro-2-amino-pyrimidine (II). The other route is the cleavage of sulfonylamide linkage, which generates the metabolite N-(4-methoxy-6-chloropyrimidin-2-yl) urea (III). Two other metabolites, saccharin (IV) and N-methyl saccharin (V), formed from metabolite II, were also identified. A metabolic pathway for the degradation of chlorimuron-ethyl by A. niger has been proposed.

  12. Polygalacturonase gene pgxB in Aspergillus niger is a virulence factor in apple fruit

    Science.gov (United States)

    Yang, Ying; Yang, Feng; Li, Yan-Hong; Liu, He-Ping; Chen, Xiao-Yan

    2017-01-01

    Aspergillus niger, a saprophytic fungus, is widely distributed in soil, air and cereals, and can cause postharvest diseases in fruit. Polygalacturonase (PG) is one of the main enzymes in fungal pathogens to degrade plant cell wall. To evaluate whether the deletion of an exo-polygalacturonase gene pgxB would influence fungal pathogenicity to fruit, pgxB gene was deleted in Aspergillus niger MA 70.15 (wild type) via homologous recombination. The ΔpgxB mutant showed similar growth behavior compared with the wild type. Pectin medium induced significant higher expression of all pectinase genes in both wild type and ΔpgxB in comparison to potato dextrose agar medium. However, the ΔpgxB mutant was less virulent on apple fruits as the necrosis diameter caused by ΔpgxB mutant was significantly smaller than that of wild type. Results of quantitive-PCR showed that, in the process of infection in apple fruit, gene expressions of polygalacturonase genes pgaI, pgaII, pgaA, pgaC, pgaD and pgaE were enhanced in ΔpgxB mutant in comparison to wild type. These results prove that, despite the increased gene expression of other polygalacturonase genes in ΔpgxB mutant, the lack of pgxB gene significantly reduced the virulence of A. niger on apple fruit, suggesting that pgxB plays an important role in the infection process on the apple fruit. PMID:28257463

  13. Efficacy and possible mechanisms of perillaldehyde in control of Aspergillus niger causing grape decay.

    Science.gov (United States)

    Tian, Jun; Wang, Yanzhen; Zeng, Hong; Li, Zongyun; Zhang, Peng; Tessema, Akalate; Peng, Xue

    2015-06-02

    A variety of plant products have been recognized for their antifungal activity and recently have attracted food industry attention for their efficacy in controlling postharvest fungal decay of fruits. The antifungal activity of perillaldehyde (PAE) was evaluated against Aspergillus niger, a known cause of grape spoilage, and possible mechanisms were explored. PAE showed notable antifungal activity against A. niger, with a minimum inhibitory concentration (MIC) and a minimum fungicidal concentration (MFC) of 0.25 and 1 μl/ml, respectively. The accumulation of mycelial biomass was also inhibited by PAE in a dose-dependent manner, completely inhibiting mycelial growth at 1 μl/ml. In vivo data confirmed that the vapour treatment of grapes with various concentrations of PAE markedly improved control of A. niger and suppressed natural decay. Concentrations of PAE of 0.075 μl/ml air showed the greatest inhibition of fungal growth compared to the controls. Further experiments indicated that PAE activated a membrane-active mechanism that inhibits ergosterol synthesis, increases membrane permeability (as evidenced by extracellular pH and conductivity measurements), and disrupts membrane integrity, leading to cell death. Our findings suggest that this membrane-active mechanism makes PAE a promising potential antifungal agent for postharvest control of grape spoilage.

  14. Optimization of ellagitannase production by Aspergillus niger GH1 by solid-state fermentation.

    Science.gov (United States)

    de la Cruz, Reynaldo; Ascacio, Juan A; Buenrostro, Juan; Sepúlveda, Leonardo; Rodríguez, Raúl; Prado-Barragán, Arely; Contreras, Juan C; Aguilera, Antonio; Aguilar, Cristóbal N

    2015-01-01

    Ellagic acid is one of the most bioactive antioxidants with important applications in pharmaceutical, cosmetic, and food industries. However, there are few biotechnological processes developed for its production, because it requires precursors (ellagitannins) and the corresponding biocatalyst (ellagitannase). The aim of this study was to optimize the culture conditions for ellagitannase production by Aspergillus niger in solid-state fermentation (SSF). The bioprocess was carried out into a column bioreactor packed with polyurethane foam impregnated with an ellagitannins solution as carbon source. Four strains of Aspergillus niger (PSH, GH1, HT4, and HC2) were evaluated for ellagitannase production. The study was performed in two experimental steps. A Plackett-Burman design was used to determine the influencing parameters on ellagitannase production. Ellagitannins concentration, KCl, and MgSO4 were determined to be the most significant parameters. Box-Behnken design was used to define the interaction of the selected parameters. The highest enzyme value was obtained by A. niger PSH at concentrations of 7.5 g/L ellagitannins, 3.04 g/L KCl, and 0.76 g/L MgSO4. The methodology followed here allowed increasing the ellagitannase activity 10 times over other researcher results (938.8 U/g ellagitannins). These results are significantly higher than those reported previously and represent an important contribution for the establishment of a new bioprocess for ellagic acid and ellagitannase production.

  15. Comparative Secretome Analysis of Aspergillus niger, Trichoderma reesei, and Penicillium oxalicum During Solid-State Fermentation.

    Science.gov (United States)

    Gong, Weili; Zhang, Huaiqiang; Liu, Shijia; Zhang, Lili; Gao, Peiji; Chen, Guanjun; Wang, Lushan

    2015-11-01

    Filamentous fungi such as Aspergillus spp., Trichoderma spp., and Penicillium spp. are frequently used to produce high concentrations of lignocellulosic enzymes. This study examined the discrepancies in the compositions and dynamic changes in the extracellular enzyme systems secreted by Aspergillus niger ATCC1015, Trichoderma reesei QM9414, and Penicillium oxalicum 114-2 cultured on corn stover and wheat bran. The results revealed different types and an abundance of monosaccharides and oligosaccharides were released during incubation, which induced the secretion of diverse glycoside hydrolases. Both the enzyme activities and isozyme numbers of the three fungal strains increased with time. A total of 279, 161, and 183 secretory proteins were detected in A. niger, T. reesei, and P. oxalicum secretomes, respectively. In the A. niger secretomes, more enzymes involved in the degradation of (galacto)mannan, xyloglucan, and the backbone of pectin distributed mostly in dicots were detected. In comparison, although P. oxalicum 114-2 hardly secreted any xyloglucanases, the diversities of enzymes involved in the degradation of xylan and β-(1,3;1,4)-D-glucan commonly found in monocots were higher. The cellulase system of P. oxalicum 114-2 was more balanced. The degradation preference provided a new perspective regarding the recomposition of lignocellulosic enzymes based on substrate types.

  16. IMPACTS OF WETLAND DEGRADATION IN NIGER DELTA NIGERIA AND ITS SIGNIFICANCE IN FLOOD CONTROL

    Directory of Open Access Journals (Sweden)

    Enwere Chidimma Loveline

    2015-08-01

    Full Text Available  Wetlands perform a wide variety of functions that include flood control, ground water recharge, shore line stabilization, storm protection and climate moderation. However, despite these huge wetland functions, it has witnessed poor appreciation and dreadful conditions. Niger Delta has witnessed constant coastal erosion and rising sea level, this has led to large portions of the landmass being eroded. This paper aims to review some environmental effects of flooding in the Niger Delta region of Nigeria to provide the desired knowledge of role that wetlands play in reducing flood impacts. However, having witnessed the flood, the experience opened my eyes to the environmental challenges facing Niger Delta with respect to Wetlands degradation, poor perception of wetland values and functions, poor environmental practices and non-implementation of environmental regulations. This memorable experience rekindled the desire and motivation to seek a solution to wetland degradation with the aim of recognizing significance of wetlands at the centre of achieving both livelihood and biodiversity improvements to address coastal flooding problem.The study therefore concludes that wetlands are very significant in flood control and thus the conservation and restoration of wetlands, should put in place measures to reduce wetland destruction.International Journal of EnvironmentVolume-4, Issue-3, June-August 2015Page: 177-184

  17. TRANSNATIONAL CRIME, HUMAN RIGHTS VIOLATION AND HUMAN TRAFFICKING IN NIGERIA’S OILRICH NIGER DELTA

    Directory of Open Access Journals (Sweden)

    Richard INGWE

    2012-12-01

    Full Text Available Despite its immense endowment in human and natural resources, Nigeria’s Niger Delta has been socially and ecologically degraded for centuries by international crime and human rights violations. External perpetrators were involved in unequal trade, trans-Atlantic slave trade, colonialism, and imperialism/neoliberalism. Some evidences of the perpetuation of these crimes in Nigeria during the post-independent period include the emasculation of the Niger Delta region through marginalistic-discriminatory government policies complemented by indigenous misrule/spoliation characterized by elite criminal stealing large portions of public funds (at an average earnings of US$20billion from the 1970s to the time of this study to stash away in foreign bank accounts. The latter combines with series of historical violations of human rights, international crime and the Delta’s cultural violation of women-girls’ rights to own/inherit property (embedded in the region’s traditional ruling institutions to engender chronic poverty of masses of Niger Deltans/Nigerians. Overwhelming poverty compels Delta girls/women to resort/succumb to human traffickers for sex work, among other modern slavery methods. Reduction/elimination of human rights violations and human trafficking require implementation of good governance capable of reforming cultural practices/beliefs and modern government invasive practices.

  18. Biocatalytic potential of laccase-like multicopper oxidases from Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Tamayo-Ramos Juan Antonio

    2012-12-01

    Full Text Available Abstract Background Laccase-like multicopper oxidases have been reported in several Aspergillus species but they remain uncharacterized. The biocatalytic potential of the Aspergillus niger fungal pigment multicopper oxidases McoA and McoB and ascomycete laccase McoG was investigated. Results The laccase-like multicopper oxidases McoA, McoB and McoG from the commonly used cell factory Aspergillus niger were homologously expressed, purified and analyzed for their biocatalytic potential. All three recombinant enzymes were monomers with apparent molecular masses ranging from 80 to 110 kDa. McoA and McoG resulted to be blue, whereas McoB was yellow. The newly obtained oxidases displayed strongly different activities towards aromatic compounds and synthetic dyes. McoB exhibited high catalytic efficiency with N,N-dimethyl-p-phenylenediamine (DMPPDA and 2,2-azino-di(3-ethylbenzthiazoline sulfonic acid (ABTS, and appeared to be a promising biocatalyst. Besides oxidizing a variety of phenolic compounds, McoB catalyzed successfully the decolorization and detoxification of the widely used textile dye malachite green. Conclusions The A. niger McoA, McoB, and McoG enzymes showed clearly different catalytic properties. Yellow McoB showed broad substrate specificity, catalyzing the oxidation of several phenolic compounds commonly present in different industrial effluents. It also harbored high decolorization and detoxification activity with the synthetic dye malachite green, showing to have an interesting potential as a new industrial biocatalyst.

  19. Heterogenic expression of genes encoding secreted proteins at the periphery of Aspergillus niger colonies.

    Science.gov (United States)

    Vinck, Arman; de Bekker, Charissa; Ossin, Adam; Ohm, Robin A; de Vries, Ronald P; Wösten, Han A B

    2011-01-01

    Colonization of a substrate by fungi starts with the invasion of exploring hyphae. These hyphae secrete enzymes that degrade the organic material into small molecules that can be taken up by the fungus to serve as nutrients. We previously showed that only part of the exploring hyphae of Aspergillus niger highly express the glucoamylase gene glaA. This was an unexpected finding since all exploring hyphae are exposed to the same environmental conditions. Using GFP as a reporter, we here demonstrate that the acid amylase gene aamA, the α-glucuronidase gene aguA, and the feruloyl esterase gene faeA of A. niger are also subject to heterogenic expression within the exploring mycelium. Coexpression studies using GFP and dTomato as reporters showed that hyphae that highly express one of these genes also highly express the other genes encoding secreted proteins. Moreover, these hyphae also highly express the amylolytic regulatory gene amyR, and the glyceraldehyde-3-phosphate dehydrogenase gene gpdA. In situ hybridization demonstrated that the high expressers are characterized by a high 18S rRNA content. Taken together, it is concluded that two subpopulations of hyphae can be distinguished within the exploring mycelium of A. niger. The experimental data indicate that these subpopulations differ in their transcriptional and translational activity.

  20. Glucoamylase starch-binding domain of Aspergillus niger B1: molecular cloning and functional characterization.

    Science.gov (United States)

    Paldi, Tzur; Levy, Ilan; Shoseyov, Oded

    2003-01-01

    Carbohydrate-binding modules (CBMs) are protein domains located within a carbohydrate-active enzyme, with a discrete fold that can be separated from the catalytic domain. Starch-binding domains (SBDs) are CBMs that are usually found at the C-terminus in many amylolytic enzymes. The SBD from Aspergillus niger B1 (CMI CC 324262) was cloned and expressed in Escherichia coli as an independent domain and the recombinant protein was purified on starch. The A. niger B1 SBD was found to be similar to SBD from A. kawachii, A. niger var. awamori and A. shirusami (95-96% identity) and was classified as a member of the CBM family 20. Characterization of SBD binding to starch indicated that it is essentially irreversible and that its affinity to cationic or anionic starch, as well as to potato or corn starch, does not differ significantly. These observations indicate that the fundamental binding area on these starches is essentially the same. Natural and chemically modified starches are among the most useful biopolymers employed in the industry. Our study demonstrates that SBD binds effectively to both anionic and cationic starch. PMID:12646045

  1. Conservation of food tree species in Niger: towards a participatory approach in rural communities

    Energy Technology Data Exchange (ETDEWEB)

    Agúndez Leal, D.; Douma, S.; Madrigal, J.; Gómez-Ramos, A.; Vicenti, B.; Alía, R.; Mahamane, A.

    2016-07-01

    Aim of the study: Indigenous woody species play an important role as a complement on the diet of rural populations in Niger, especially in periods of food scarcity. However, these species are nowadays overexploited and management programmes are necessary to conserve them. In order to design a conservation programme for edible woody species, this paper presents a sociological analysis about the use of edible woody species and their products during shortage periods in Niger. Area of study: Four villages in two distinct agro-ecological regions were selected to conduct structured enquiries based on focus group discussions and surveys with key informants. Material and Methods: Perceptions of the conservation status of these species were identified; as well the factors affecting food values, perceptions, management and collection practices. Main results: Results show that B. senegalensis was a staple food in the driest areas, and M. crassifolia was used for fodder and human consumption in the most critical situations. The local communities related the drivers of species conservation status specific to the agro-ecological regions, and gender and ethnic differences were also identified. Research highlights: Understanding these factors constitutes a first step towards adaptive management strategies for the conservation of woody food species in rural communities of Niger. (Author)

  2. Putative Aspergillus niger-induced oxalate nephrosis in sheep : clinical communication

    Directory of Open Access Journals (Sweden)

    C.J. Botha

    2009-05-01

    Full Text Available A sheep farmer provided a maize-based brewer's grain (mieliemaroek and bales of Eragrostis curvula hay to ewes and their lambs, kept on zero-grazing in pens. The 'mieliemaroek' was visibly mouldy. After 14 days in the feedlot, clinical signs, including generalised weakness, ataxia of the hind limbs, tremors and recumbency, were noticed. Six ewes died within a period of 7 days. A post mortem examination was performed on 1 ewe. The carcass appeared to be cachectic with mild effusions into the body cavities; mild lung congestion and pallor of the kidneys were observed. Microscopical evaluation revealed nephrosis and birefringent oxalate crystals in the renal tubules when viewed under polarised light. A provisional diagnosis of oxalate nephrosis with subsequent kidney failure was made. Amongst other fungi, Aspergillus niger was isolated from 'mieliemaroek' samples submitted for fungal culture and identification. As A. niger is known to synthesise oxalates, a qualitative screen to detect oxalic acid in the mieliemaroek and purified A. niger isolates was performed using high-performance liquid chromatography (HPLC. Oxalic acid was detected, which supported a diagnosis of soluble oxalate-induced nephropathy.

  3. Confined gravity flow sedimentary process and its impact on the lower continental slope,Niger Delta

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    There is active gravity flow sedimentation on the lower continental slope of Niger Delta. High-resolution 3-D seismic data enable a detailed study on the gravity flow deposition process and its impact. The lower continental slope of Niger Delta is characterized by a stepped complex topography, which resulted from gravity sliding and spreading during Miocene and Pliocene. Two types of accommodations are identified on the slope: ponded accommodation as isolated sub-basins and healed slope accommodation as connected tortuous corridors, where multi-scale submarine fans and submarine channels developed. Gravity flow deposition process is affected by the characteristics of gravity flows and the receiving basin. At the early stage, gravity flow deposition process was dominated by "fill and spill" pattern in the ponded accommodation, whereas it was confined to the healed slope accommodation during the late stage. On the lower continental slope of Niger Delta, complex slope topography controlled the distribution and evolution of the gravity flow, producing complicated gravity depositional patterns.

  4. Oil exploitation and its socioeconomic effects on the Niger Delta region of Nigeria.

    Science.gov (United States)

    Elum, Z A; Mopipi, K; Henri-Ukoha, A

    2016-07-01

    The oil exploration and exploitation industry which is majorly centred in the Niger Delta region is without doubt currently the most important earner of foreign exchange to the Nigerian economy. The Niger Delta is home to an extraordinary variety of people; mostly fishers and farmers with a history of rich cultural heritage. However, the region is suffering from devastating oil pollution. Although the effects of oil spill depend on factors such as size or area of spill and geographical location, the socioeconomic and environmental costs of oil production can be extensive; these range from destruction of wildlife, biodiversity loss, air and water pollution, degradation of farmland and damage to aquatic ecosystems. The paper reviews the adverse effects of oil exploitation on the Niger Delta region. It researches the common belief that government and oil multinationals are negatively disposed to the socioeconomic and environmental wellbeing of host communities especially in events of oil spillage. The paper reveals that oil exploitation has increased the rate of environmental degradation and has perpetuated food insecurity as a result of death of fish and crops as well as loss of farm lands and viable rivers for fishing activities leading to loss of livelihood. The paper supports the call for multinationals operating in the region to modernise operating infrastructure and equipment in order to prevent avoidable oil spillages that often lead to community restiveness, and more so, intensification of joint efforts between oil multinationals and government in the capital development of the region is very important.

  5. Climate Change and Poverty: Sustainable Approach in the Niger Delta Region of Nigeria

    Energy Technology Data Exchange (ETDEWEB)

    Ogbeibu, A.E. [University of Benin, Benin City, Edo State (Nigeria). Department of Animal and Environmental Biology; Uyigue, E. [Community Research and Development Centre, Benin, Edo State (Nigeria)

    2008-09-30

    The Niger Delta region is the bedrock of Nigeria's oil production, which accounts for 97% of the government total revenue. Since the discovery of oil in the region, oil exploration and exploitation have caused severe climate and environmental changes which have impacted the lives of the inhabitant adversely. Prior to the discovery of oil, the people of the Niger Delta made their living from the exploitation of the resources of the land, water and forest as farmers, fishermen and hunters, this made them attached to and protective of their environment. The devastating impacts of the oil industries on farmland, crops, economic trees, creeks, lakes and other components of the environment are so severe that the people can no longer engage in productive farming, fishing and hunting as they use to do. The most affected groups are women and children. This paper highlights in details the climatic and environmental changes that have occurred in the Niger Delta region and shows the relationship between these changes and poverty. It reveals the weaknesses and deficiencies in the Nigerian Constitution in administering environmental rights to the people and suggests institutional and constitutional solution to the environmental degradation in the region and elsewhere.

  6. Factors affecting treatment of palm oil mill effluent using enzyme from Aspergillus niger ATCC 6275

    Directory of Open Access Journals (Sweden)

    Chantaphaso, S.

    2001-11-01

    Full Text Available Powdered enzyme was produced by freeze-drying the enzyme solution extracted from 3 days culture of Aspergillus niger ATCC 6275 on palm cake with the addition of 0.2% glucose and 2% urea. The product yield was 38% by weight. The half-life of the enzyme was 9 months keeping at 4ºC. The enzyme was tested with decanter effluent with different characteristics from two palm oil mills. The decanter effluent possessing high suspended solid (SS and low oil (9.5 g/l content was selected for studying the factors affecting the separation of SS and oil as bulking solid. Results indicated that the effluent must contain oil not less than 15 g/l so that the bulking solid would occur from the reaction of the enzyme (with xylanase activity of 200 U/ ml after incubation at 40ºC for 6 h. Minimum concentrations of the enzyme from A. niger ATCC 6275 and commercial xylanase (Meicellase were 200 and 600 U/ml, respectively. The optimum pH was 4.5. Treatment of palm oil mill effluent by the enzyme from A. niger ATCC 6275 for 3 h under the optimum conditions resulted in 78% separation of suspended solids with oil & grease removal of 95% and COD reduction of 35%.

  7. Lethal effects of Aspergillus niger against mosquitoes vector of filaria, malaria, and dengue: a liquid mycoadulticide.

    Science.gov (United States)

    Singh, Gavendra; Prakash, Soam

    2012-01-01

    Aspergillus niger is a fungus of the genus Aspergillus. It has caused a disease called black mold on certain fruits and vegetables. The culture filtrates released from the A. niger ATCC 66566 were grown in Czapek dox broth (CDB) then filtered with flash chromatograph and were used for the bioassay after a growth of thirty days. The result demonstrated these mortalities with LC(50), LC(90), and LC(99) values of Culex quinquefasciatus 0.76, 3.06, and 4.75, Anopheles stephensi 1.43, 3.2, and 3.86, and Aedes aegypti 1.43, 2.2, and 4.1 μl/cm(2), after exposure of seven hours. We have calculated significant LT(90) values of Cx. quinquefasciatus 4.5, An. stephensi 3.54, and Ae. aegypti 6.0 hrs, respectively. This liquid spray of fungal culture isolate of A. niger can reduce malaria, dengue, and filarial transmission. These results significantly support broadening the current vector control paradigm beyond chemical adulticides.

  8. Lethal Effects of Aspergillus niger against Mosquitoes Vector of Filaria, Malaria, and Dengue: A Liquid Mycoadulticide

    Directory of Open Access Journals (Sweden)

    Gavendra Singh

    2012-01-01

    Full Text Available Aspergillus niger is a fungus of the genus Aspergillus. It has caused a disease called black mold on certain fruits and vegetables. The culture filtrates released from the A. niger ATCC 66566 were grown in Czapek dox broth (CDB then filtered with flash chromatograph and were used for the bioassay after a growth of thirty days. The result demonstrated these mortalities with LC50, LC90, and LC99 values of Culex quinquefasciatus 0.76, 3.06, and 4.75, Anopheles stephensi 1.43, 3.2, and 3.86, and Aedes aegypti 1.43, 2.2, and 4.1 μl/cm2, after exposure of seven hours. We have calculated significant LT90 values of Cx. quinquefasciatus 4.5, An. stephensi 3.54, and Ae. aegypti 6.0 hrs, respectively. This liquid spray of fungal culture isolate of A. niger can reduce malaria, dengue, and filarial transmission. These results significantly support broadening the current vector control paradigm beyond chemical adulticides.

  9. Apoptosis-inducing activity of Helleborus niger in ALL and AML.

    Science.gov (United States)

    Jesse, Patrick; Mottke, Gritt; Eberle, Jürgen; Seifert, Georg; Henze, Günter; Prokop, Aram

    2009-04-01

    Helleborus niger is used in the adjuvant treatment of different tumors in anthroposophical medicine. Indications include various types of brain tumors in children, as well as prostate cancer, leukemia and lymphoma. Our aim was to investigate the therapeutic effects of these extracts apart from the traditional use. : We used an aqueous whole plant extract of H. niger in different cancer and leukemia cell lines and primary cells of patients with childhood ALL and AML and identified the main mechanisms of action. A strong inhibition of proliferation is caused by specific apoptosis induction, which is executed via the mitochondrial pathway and caspase-3 processing. Apoptosis could be detected in lymphoma (BJAB), leukemia (Reh, Nalm6, Sup-B15) and melanoma (Mel-HO) cells and overcomes a Bcl-2-mediated block of apoptosis. In primary cells of patients with childhood ALL and AML, which were partly poor responding to doxorubicin and daunorubicin, a strong apoptosis induction was determined. In combination with the vinca alkaloid vincristine, strong synergistic effects were detected in BJAB cells. We demonstrate in vitro efficacy of H. niger extract in cells of hematological malignancies; these studies should encourage in vivo experiments. Copyright 2008 Wiley-Liss, Inc.

  10. Mineral Fiber Toxicology

    Science.gov (United States)

    The chemical and physical properties of different forms of mineral fibers impact biopersistence and pathology in the lung. Fiber chemistry, length, aspect ratio, surface area and dose are critical factors determining mineral fiber-associated health effects including cancer and as...

  11. Mineral commodity summaries 2017

    Science.gov (United States)

    Ober, Joyce A.

    2017-01-31

    This report is the earliest Government publication to furnish estimates covering 2016 nonfuel mineral industry data. Data sheets contain information on the domestic industry structure, Government programs, tariffs, and 5-year salient statistics for more than 90 individual minerals and materials.

  12. Prospecting for the incidence of genes involved in ochratoxin and fumonisin biosynthesis in Brazilian strains of Aspergillus niger and Aspergillus welwitschiae.

    Science.gov (United States)

    Massi, Fernanda Pelisson; Sartori, Daniele; de Souza Ferranti, Larissa; Iamanaka, Beatriz Thie; Taniwaki, Marta Hiromi; Vieira, Maria Lucia Carneiro; Fungaro, Maria Helena Pelegrinelli

    2016-03-16

    Aspergillus niger "aggregate" is an informal taxonomic rank that represents a group of species from the section Nigri. Among A. niger "aggregate" species Aspergillus niger sensu stricto and its cryptic species Aspergillus welwitschiae (=Aspergillus awamori sensu Perrone) are proven as ochratoxin A and fumonisin B2 producing species. A. niger has been frequently found in tropical and subtropical foods. A. welwitschiae is a new species, which was recently dismembered from the A. niger taxon. These species are morphologically very similar and molecular data are indispensable for their identification. A total of 175 Brazilian isolates previously identified as A. niger collected from dried fruits, Brazil nuts, coffee beans, grapes, cocoa and onions were investigated in this study. Based on partial calmodulin gene sequences about one-half of our isolates were identified as A. welwitschiae. This new species was the predominant species in onions analyzed in Brazil. A. niger and A. welwitschiae differ in their ability to produce ochratoxin A and fumonisin B2. Among A. niger isolates, approximately 32% were OTA producers, but in contrast only 1% of the A. welwitschiae isolates revealed the ability to produce ochratoxin A. Regarding fumonisin B2 production, there was a higher frequency of FB2 producing isolates in A. niger (74%) compared to A. welwitschiae (34%). Because not all A. niger and A. welwitschiae strains produce ochratoxin A and fumonisin B2, in this study a multiplex PCR was developed for detecting the presence of essential genes involved in ochratoxin (polyketide synthase and radHflavin-dependent halogenase) and fumonisin (α-oxoamine synthase) biosynthesis in the genome of A. niger and A. welwitschiae isolates. The frequency of strains harboring the mycotoxin genes was markedly different between A. niger and A. welwitschiae. All OTA producing isolates of A. niger and A. welwitschiae showed in their genome the pks and radH genes, and 95.2% of the nonproducing

  13. Marine Mineral Exploration

    DEFF Research Database (Denmark)

    The past 20 years have seen extensive marine exploration work by the major industrialized countries. Studies have, in part, been concentrated on Pacific manganese nodule occurrences and on massive sulfides on mid-oceanic ridges. An international jurisdictional framework of the sea-bed mineral...... in EEZ areas are fairly unknown; many areas need detailed mapping and mineral exploration, and the majority of coastal or island states with large EEZ areas have little experience in exploration for marine hard minerals. This book describes the systematic steps in marine mineral exploration....... Such exploration requires knowledge of mineral deposits and models of their formation, of geophysical and geochemical exploration methods, and of data evaluation and interpretation methods. These topics are described in detail by an international group of authors. A short description is also given of marine...

  14. Production and action pattern of inulinase from Aspergillus Niger-245: hydrolysis of inulin from several sources Produção e mecanismo de ação de inulinase de Aspergillus niger-245: hidrólise de inulinas de diferentes origens

    Directory of Open Access Journals (Sweden)

    Vinícius D’Arcadia Cruz

    1998-10-01

    Full Text Available A strain of Aspergillus niger isolated from soil samples showed great capacity to produce extracellular inulinase. Although the enzyme has been synthesized in presence of monosaccharides, sucrose and sugar cane molasse, the productivity was significantly higher (pUma linhagem de Aspergillus niger isolada de amostras de solo mostrou grande capacidade de produzir inulinase extracelular. Embora a enzima tenha sido sintetizada na presença de monossacarídeos, sacarose e melaço de cana, a produtividade foi significativamente maior (p<0.01 quando o microrganismo foi inoculado em meios formulados com extrato de dália e inulina pura, como fontes de carbono. Em relação à fonte de nitrogênio, os melhores resultados foram obtidos com caseína e outras fontes de nitrogênio proteico, comparativamente ao nitrogênio mineral. Entretanto, somente foi encontrada significância (p<0.01 entre a produtividade obtida nos meios preparados com caseína e sulfato de amônia. O pH ótimo da enzima purificada foi localizado entre 4.0 e 4.5 e a temperatura ótima a 60ºC. Quando tratada por 30 minutos nesta temperatura nenhuma perda de atividade foi observada. A enzima mostrou capacidade de hidrolisar sacarose, rafinose e inulina, da qual liberou apenas unidades de frutose, mostrando, portanto, um mecanismo de exo-ação. Atuando sobre inulinas de diversas fontes, a enzima mostrou maior velocidade de hidrólise sobre o polissacarídeo da chicória, comparativamente, às inulinas de raízes de dalia e alcachofra.

  15. 78 FR 65268 - Certain Oil Country Tubular Goods From India, the Republic of Korea, the Republic of the...

    Science.gov (United States)

    2013-10-31

    ..., A-823-815, A-552-817] Certain Oil Country Tubular Goods From India, the Republic of Korea, the Republic of the Philippines, Saudi Arabia, Taiwan, Thailand, the Republic of Turkey, Ukraine, and the... Nair at (202) 482- 3813 (Thailand); Catherine Cartsos at (202) 482-1757 (Turkey); David Lindgren...

  16. Collective violence and attitudes of women toward intimate partner violence: Evidence from the Niger Delta.

    Science.gov (United States)

    Antai, Diddy; Antai, Justina

    2009-06-09

    The Niger Delta region of Nigeria has been undergoing collective violence for over 25 years, which has constituted a major public health problem. The objectives of this study were to investigate the predictors of women's attitudes toward intimate partner violence in the Niger Delta in comparison to that of women in other parts of Nigeria. The 2003 Nigeria Demographic and Health Survey was used for this study. Respondents were selected using a stratified two-stage cluster sampling procedure through which 3725 women were selected and interviewed. These women contributed 6029 live born children born to the survey. Internal consistency of the measure of the women's attitudes towards intimate partner violence against a woman was assessed using Cronbach's alpha (alpha). Percentage distributions of the relevant characteristics of the respondents were carried out, and multivariable logistic regression analysis was used to measure the magnitude and direction of the relationship between the outcome and predictor variables were expressed as odds ratios (OR) and statistical significance was determined at the 95 percent confident interval level (CI). Tolerance for intimate partner violence among the women in the Niger delta (47 percent) was higher than that of women from the rest of the country (42 percent). Rural residence, lower household wealth, lower status occupations, and media access (newspaper and radio) were associated with lower risk of justifying IPV among the women in the Niger Delta. In contrast full or partial autonomy in household decisions regarding food to be cooked, and access to television were associated with a lower risk of justifying violence. The increased justification of intimate partner violence among the women in the Niger Delta could be explained by a combination of factors, among which are cognitive dissonance theory (attitudes that do not fit with other opinions they hold as a means of coping with their situation), ecological theory (behaviour or

  17. Collective violence and attitudes of women toward intimate partner violence: Evidence from the Niger Delta

    Directory of Open Access Journals (Sweden)

    Antai Diddy

    2009-06-01

    Full Text Available Abstract Background The Niger Delta region of Nigeria has been undergoing collective violence for over 25 years, which has constituted a major public health problem. The objectives of this study were to investigate the predictors of women's attitudes toward intimate partner violence in the Niger Delta in comparison to that of women in other parts of Nigeria. Methods The 2003 Nigeria Demographic and Health Survey was used for this study. Respondents were selected using a stratified two-stage cluster sampling procedure through which 3725 women were selected and interviewed. These women contributed 6029 live born children born to the survey. Internal consistency of the measure of the women's attitudes towards intimate partner violence against a woman was assessed using Cronbach's alpha (α. Percentage distributions of the relevant characteristics of the respondents were carried out, and multivariable logistic regression analysis was used to measure the magnitude and direction of the relationship between the outcome and predictor variables were expressed as odds ratios (OR and statistical significance was determined at the 95 percent confident interval level (CI. Results Tolerance for intimate partner violence among the women in the Niger delta (47 percent was higher than that of women from the rest of the country (42 percent. Rural residence, lower household wealth, lower status occupations, and media access (newspaper and radio were associated with lower risk of justifying IPV among the women in the Niger Delta. In contrast full or partial autonomy in household decisions regarding food to be cooked, and access to television were associated with a lower risk of justifying violence. Conclusion The increased justification of intimate partner violence among the women in the Niger Delta could be explained by a combination of factors, among which are cognitive dissonance theory (attitudes that do not fit with other opinions they hold as a means of

  18. Physicochemical Properties Analysis and Secretome of Aspergillus niger in Fermented Rapeseed Meal.

    Directory of Open Access Journals (Sweden)

    Changyou Shi

    Full Text Available The nutrient digestibility and feeding value of rapeseed meal (RSM for non-ruminant animals is poor due to the presence of anti-nutritional substances such as glucosinolate, phytic acid, crude fiber etc. In the present study, a solid state fermentation (SSF using Aspergillus niger was carried out with the purpose of improving the nutritional quality of RSM. The chemical composition and physicochemical properties of RSM before and after fermentation were compared. To further understand possible mechanism of solid state fermentation, the composition of extracellular enzymes secreted by Aspergillus niger during fermentation was analysed using two-dimentional difference gel electrophoresis (2D-DIGE combined with matrix assisted laser desorption ionization-time of flight-mass spectrometer (MALDI-TOF-MS. Results of the present study indicated that SSF had significant effects on chemical composition of RSM. The fermented rapeseed meal (FRSM contained more crude protein (CP and amino acid (AA (except His than unfermented RSM. Notably, the small peptide in FRSM was 2.26 time larger than that in unfermented RSM. Concentrations of anti-nutritional substrates in FRSM including neutral detergent fiber (NDF, glucosinolates, isothiocyanate, oxazolidithione, and phytic acid declined (P < 0.05 by 13.47, 43.07, 55.64, 44.68 and 86.09%, respectively, compared with unfermented RSM. A. niger fermentation disrupted the surface structure, changed macromolecular organic compounds, and reduced the protein molecular weights of RSM substrate. Total proteins of raw RSM and FRSM were separated and 51 protein spots were selected for mass spectrometry according to 2D-DIGE map. In identified proteins, there were 15 extracellular hydrolases secreted by A. niger including glucoamylase, acid protease, beta-glucanase, arabinofuranosidase, xylanase, and phytase. Some antioxidant related enzymes also were identified. These findings suggested that A. niger is able to secrete many

  19. Deprivation and Resistance: Environmental Crisis, Political Action, and Conflict Resolution in the Niger Delta since the 1980s

    Directory of Open Access Journals (Sweden)

    David Aworawo

    2013-05-01

    Full Text Available The interlocking relationship between environmental degradation, poverty,and violent conflict has been a prominent theme contained within the literature on sustainable development and conflict resolution since the midtwentieth century. While some analysts have argued that violence has not been limited to the poor and deprived, many have concluded from various studies that the devastation of the environment, poverty, and conflict are inextricably intertwined. This article examines this theme by analyzing the pattern of violence and nature of conflict resolution in the oil-producing enclave of the Niger Delta in the past three decades. A report of the United Nations Environment Programme on parts of the Niger Delta published in August 2011 reveals that the area is one of the most intensely polluted in the world. The report confirms the conclusion of several other earlier reports on the Niger Delta, which state that activities relating to the exploitation of oil and gas have led to intense environmental pollution and extreme poverty and that those conditions have spawned violence. The article is exploratory and analytical. It draws from diverse sources, including government records and reports of intergovernmental and non-governmental organizations as well as oral information gathered by the author from fieldwork conducted across the Niger Delta between 2007 and 2012, to explore the nature of the Niger Delta crisis from the 1980s until the present. The article argues that environmental degradation is central to the Niger Delta crisis, as it has hampered rural economic activities and posed a threat to human security. The article concludes that the effective tackling of the environmental crisis in the Niger Delta would surely reduce poverty and violence in the area.

  20. The opposite roles of agdA and glaA on citric acid production in Aspergillus niger.

    Science.gov (United States)

    Wang, Lu; Cao, Zhanglei; Hou, Li; Yin, Liuhua; Wang, Dawei; Gao, Qiang; Wu, Zhenqiang; Wang, Depei

    2016-07-01

    Citric acid is produced by an industrial-scale process of fermentation using Aspergillus niger as a microbial cell factory. However, citric acid production was hindered by the non-fermentable isomaltose and insufficient saccharification ability in A. niger when liquefied corn starch was used as a raw material. In this study, A. niger TNA 101ΔagdA was constructed by deletion of the α-glucosidase-encoding agdA gene in A. niger CGMCC 10142 genome using Agrobacterium tumefaciens-mediated transformation. The transformants A. niger OG 1, OG 17, and OG 31 then underwent overexpression of glucoamylase in A. niger TNA 101ΔagdA. The results showed that the α-glucosidase activity of TNA 101ΔagdA was decreased by 62.5 % compared with CGMCC 10142, and isomaltose was almost undetectable in the fermentation broth. The glucoamylase activity of the transformants OG 1 and OG 17 increased by 34.5 and 16.89 % compared with that of TNA 101ΔagdA, respectively. In addition, for the recombinants TNA 101ΔagdA, OG 1 and OG 17, there were no apparent defects in the growth development. Consequently, in comparison with CGMCC 10142, TNA 101ΔagdA and OG 1 decreased the residual reducing sugar by 52.95 and 88.24 %, respectively, and correspondingly increased citric acid production at the end of fermentation by 8.68 and 16.87 %. Citric acid production was further improved by decreasing the non-fermentable residual sugar and increasing utilization rate of corn starch material in A. niger. Besides, the successive saccharification and citric acid fermentation processes were successfully integrated into one step.

  1. POTENSI DARI KAPANG Aspergilus niger, Rhizophus oryzae DAN Neurospora sitophila SEBAGAI PENGHASIL EZIM FITASE DAN AMILASE PADA SUBSTRATE AMPAS TAHU

    Directory of Open Access Journals (Sweden)

    Atit - Kanti

    2017-02-01

    Full Text Available Penambahan enzim hidrolisis untuk pakan ternak dapat meningkatkan nilai nutrisi pakan. Penelitian bertujuan untuk mendapatkan kondisi optimal untuk produksi enzim amilase dan fitase pada media ampas tahu menggunakan Aspergilus niger, Rhizophus oryzae dan Neurospora sitophila. Uji kemampuan produksi enzim fitase dan amilase oleh Aspergilus niger, Rhizophus oryzae dan Neurospora sitophila dilakukan menggunakan media ampas tahu yang disterilisasi. Pemilihan ketiga isolat ini diawali dengan uji produksi enzim amilase pada kultur cair yang mengandung 2 % pati, dan uji fitase dilakukan pada media yang mengandung 0.5 % sodium fitat. Hasil uji pada medium cair selanjutnya digunakan untuk uji produksi enzim fitase dan fitase pada sistem fermentasi padat (SSF menggunakan ampas tahu sebagai media fermentasi. Untuk mendapatkan produksi enzim yang tinggi dilakukan melalui optimasi waktu inkubasi, suhu inkubasi dan pH media. Fitase dan amilase dapat diproduksi dengan media ampas tahu oleh R. oryzae, A. niger dan N. sitophila. Kondisi optimum untuk produksi fitase, yaitu waktu inkubasi pada hari keempat untuk ketiga kapang, suhu 25 °C untuk R. oryzae dan A. niger, suhu 30°C untuk N. sitophila, pH 8 untuk R. oryzae, pH 6 untuk Aspergillus niger dan N. Sitophila. Neurospora sitophila menghasilkan amilase optimum pada suhu 35°C, sedangkan Aspergillus niger dan Rhizopus oryzae optimum pada suhu 30°C. Penurunan aktivitas produksi amilase menurun oleh R. oryzae pada suhu 40°C. Amilase diproduksi optimal pada pH 6-7. Pakan ternak yang mengandung asam fitat mampu dihidrolisis oleh fitase pada kondisi optimum. Ketiga kapang juga menghasilkan enzim amilase pada media ampas tahu mengindikasikan bahwa ampas tahu merupakan susbtrat yang baik untuk produksi enzim hidrolisis yang berguna untuk meningkatkan nilai nutrisi pakan ternak. (Kata kunci: Amilase, Aspergilus niger, Neurospora sitophila, phytase, Rhizophus oryzae

  2. Lacustrine sediments and Holocene climates in the southern Sahara: the example of paleolakes in the Grand Erg of Bilma (Zoo Baba and Dibella, eastern Niger)

    Science.gov (United States)

    Grunert, J.; Baumhauer, R.; Völkel, J.

    Two endoreic depressions of the central Erg of Bilma/eastern Republic of Niger are described here. Special interest is given to widespread lacustrine sediments (diatomites) in the depressions, indicating paleolakes with an extension of some 10 km 2. The minimum depth of the lakes has been found to be 25 m (Zoo Baba) and 36 m (Dibella). At Dibella there is evidence of two lacustrine phases of Early Holocene (9785-7890 years B.P.) and of Mid-Holocene age (about 6500 years B.P.). At Zoo Baba only one lacustrine phase of Mid-Holocene age (about 6000-5370 years B.P.) can be proven for Zoo Baba. The difference between the Early- and Mid-Holocene diatomites Di I and Di II is based not only on radiocarbon data but also on geomorphological characteristics. Despite the small distance of only 70 km between the two depressions, the reconstruction of pluvial water chemistry particularly by analyzing the diatoms shows great differences. The Mid-Holocene Zoo Baba lake was a freshwater lake; the Early- and Mid-Holocene Dibella lakes obviously contained brackish water with great fluctuations of salinity. An explanation may be given by the varying groundwater influence during the pluvial periods. It is supposed that Zoo Baba has been touched by the large Kaouar/Bilma aquifer while Dibella has been influenced by a smaller local aquifer. Any groundwater supply from Paleo-Chad can be excluded. Both the rising of groundwater table and of lake levels must have been induced by a largely increased annual precipitation rate (today 20-40 mm only), combined with a very effective reduction in evaporation rate. Based on lacrustine sediments, paleosoils and geomorphological features (fossil landslides of Zoo Baba), the Early Holocene annual precipitation rate is estimated at least at 300-400 mm, the Mid-Holocene rate at 200-300 mm. The special character of precipitations cannot be reconstructed.

  3. Mineral Commodity Summaries 2008

    Science.gov (United States)

    ,

    2008-01-01

    Each chapter of the 2008 edition of the U.S. Geological Survey (USGS) Mineral Commodity Summaries (MCS) includes information on events, trends, and issues for each mineral commodity as well as discussions and tabular presentations on domestic industry structure, Government programs, tariffs, 5-year salient statistics, and world production and resources. The MCS is the earliest comprehensive source of 2007 mineral production data for the world. More than 90 individual minerals and materials are covered by two-page synopses. National reserves and reserve base information for most mineral commodities found in this report, including those for the United States, are derived from a variety of sources. The ideal source of such information would be comprehensive evaluations that apply the same criteria to deposits in different geographic areas and report the results by country. In the absence of such evaluations, national reserves and reserve base estimates compiled by countries for selected mineral commodities are a primary source of national reserves and reserve base information. Lacking national assessment information by governments, sources such as academic articles, company reports, common business practice, presentations by company representatives, and trade journal articles, or a combination of these, serve as the basis for national reserves and reserve base information reported in the mineral commodity sections of this publication. A national estimate may be assembled from the following: historically reported reserves and reserve base information carried for years without alteration because no new information is available; historically reported reserves and reserve base reduced by the amount of historical production; and company reported reserves. International minerals availability studies conducted by the U.S. Bureau of Mines, before 1996, and estimates of identified resources by an international collaborative effort (the International Strategic Minerals

  4. Why Mineral Interfaces Matter

    Science.gov (United States)

    Putnis, Andrew; Putnis, Christine V.

    2015-04-01

    While it is obvious that reactions between a mineral and an aqueous solution take place at the mineral-fluid interface it is only relatively recently that high spatial resolution studies have demonstrated how the local structure of the mineral surface and the chemical composition of the fluid at the interface control both the short-range and the long-range consequences of mineral-fluid interaction. Long-range consequences of fluid-mineral interaction control element cycles in the earth, the formation of ore-deposits, the chemical composition of the oceans through weathering of rocks and hence climate changes. Although weathering is clearly related to mineral dissolution, to what extent do experimentally measured dissolution rates of minerals help to understand weathering, especially weathering mechanisms? This question is related to the short-range, local reactions that take place when a mineral, that is not stable in the fluid, begins to dissolve. In this case the fluid composition at the interface will become supersaturated with respect to a different phase or phases. This may be a different composition of the same mineral e.g. a Ca-rich feldspar dissolving in a Na-rich solution results in a fluid at the interface which may be supersaturated with respect to an Na-rich feldspar. Alternatively, the interfacial fluid could be supersaturated with respect to a different mineral e.g. an Na-rich zeolite, depending on the temperature. Numerous experiments have shown that the precipitation of a more stable phase at the mineral-fluid interface results in a coupling between the dissolution and the precipitation, and the replacement of one mineral by another. This process separates the short-range mechanisms which depend only on the composition of the interfacial solution, and the long-range consequences that depend on the composition of the residual fluid released from the reacting parent mineral. Typically such residual fluids may carry metal ions tens to hundreds of

  5. Mineral potential for nickel, copper, platinum group elements(PGE), and chromium deposits hosted in ultramafic rocks in the Islamic Republic of Mauritania (phase V, deliverable 67): Chapter G in Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)

    Science.gov (United States)

    Taylor, Cliff D.; Marsh, Erin; Anderson, Eric D.

    2015-01-01

    PRISM-I summary documents mention the presence of mafic-ultramafic igneous intrusive rocks in several areas of Mauritania and a number of chromium (Cr) and copper-nickel (Cu-Ni (±Co, Au)) occurrences associated with them. Permissive geologic settings generally include greenstone belts of any age, layered mafic-ultramafic and unlayered gabbro-anorthosite intrusive complexes in cratonic settings, ophiolite complexes, flood basalt provinces, and fluid-rich shear zones cutting accumulations of mafic-ultramafic rocks. Regions of Mauritania having these characteristics that are discussed in PRISM-I texts include the Mesoarchean greenstone belts of the TasiastTijirit terrane in the southwestern Rgueïbat Shield, two separate layered ultramafic complexes in the Amsaga Complex west of Atar, serpentinized metadunites in Mesoarchean rocks of the Rgueïbat Shield in the Zednes map sheet, several lateritized annular mafic-ultramafic complexes in the Paleoproterozoic northwestern portion of the Rgueïbat Shield, and the serpentinized ophiolitic segments of the Gorgol Noir Complex in the axial portion of the southern Mauritanides. Bureau de Recherches Géologiques et Minières (BRGM) work in the “Extreme Sud” zone also suggests that small copper occurrences associated with the extensive Jurassic microgabbroic intrusive rocks in the Taoudeni Basin of southeastern Mauritania could have potential for magmatic Cu-Ni (PGE, Co, Au) sulfide mineralization. Similarly, Jurassic mafic intrusive rocks in the northeastern Taoudeni Basin may be permissive. Known magmatic Cu-Ni deposits of these types in Mauritania are few in number and some uncertainty exists as to the nature of several of the more important ones.

  6. 78 FR 74115 - Monosodium Glutamate From the People's Republic of China and the Republic of Indonesia...

    Science.gov (United States)

    2013-12-10

    ... Indonesia: Postponement of Preliminary Determination in the Countervailing Duty Investigations AGENCY... (PRC)); Nicholas Czajkowski at (202) 482- 1395 (the Republic of Indonesia (Indonesia)), AD/CVD... investigations of monosodium glutamate from Indonesia and the PRC.\\1\\ Currently, the preliminary...

  7. Mineral facilities of Europe

    Science.gov (United States)

    Almanzar, Francisco; Baker, Michael S.; Elias, Nurudeen; Guzman, Eric

    2010-01-01

    This map displays over 1,700 records of mineral facilities within the countries of Europe and western Eurasia. Each record represents one commodity and one facility type at a single geographic location. Facility types include mines, oil and gas fields, and plants, such as refineries, smelters, and mills. Common commodities of interest include aluminum, cement, coal, copper, gold, iron and steel, lead, nickel, petroleum, salt, silver, and zinc. Records include attributes, such as commodity, country, location, company name, facility type and capacity (if applicable), and latitude and longitude geographical coordinates (in both degrees-minutes-seconds and decimal degrees). The data shown on this map and in table 1 were compiled from multiple sources, including (1) the most recently available data from the U.S. Geological Survey (USGS) Minerals Yearbook (Europe and Central Eurasia volume), (2) mineral statistics and information from the USGS Minerals Information Web site (http://minerals.usgs.gov/minerals/pubs/country/europe.html), and (3) data collected by the USGS minerals information country specialists from sources, such as statistical publications of individual countries, annual reports and press releases of operating companies, and trade journals. Data reflect the most recently published table of industry structure for each country at the time of this publication. Additional information is available from the country specialists listed in table 2.

  8. Comparison of selected CAP measures in the Czech Republic and Republic of Slovenia

    Directory of Open Access Journals (Sweden)

    Hana Svobodová

    2008-12-01

    Full Text Available Czech Republic and Republic Slovenia are the members of European Union for four years already. Membership in EU required the adoption of European legal order, in agriculture the adoption of Common agricultural policy (CAP which brought many changes into agricultural sector. The article deals with selected measures of CAP and tries to describe their settings and differences in both countries. A case study is also included – the comparison of selected measures in one Czech and one Slovenian region.

  9. CPAFFC Delegation Visits Democratic Republic of the Congo and Republic of Congo

    Institute of Scientific and Technical Information of China (English)

    Xu; Liya

    2016-01-01

    At the invitation of Andre Kimbuta,mayor of Kinshasa in the Democratic Republic of the Congo,and Jean Marie Ewengue,mayor of Oyo city,Republic of Congo,a CPAFFC delegation led by Lin Yi,the group’s vice-president,visited the two countries from Sept 22 to 30.During the visit to the DRC,the delegation met with Edouard Mokolo

  10. Mineral resources of Antarctica

    Science.gov (United States)

    Compiled and edited by Wright, Nancy A.; Williams, Paul L.

    1974-01-01

    Although the existence of mineral deposits in Antarctica is highly probable, the chances of finding them are quite small. Minerals have been found there in great variety but only as occurrences. Manganese nodules, water (as ice), geothermal energy, coal, petroleum, and natural gas are potential resources that could perhaps be exploited in the future. On the basis of known mineral occurrences in Antarctica and relationships between geologic provinces of Antarctica and those of neighboring Gondwana continents, the best discovery probability for a base-metal deposit in any part of Antarctica is in the Andean orogen; it is estimated to be 0.075 (75 chances in 1,000).

  11. Gravimetric maps of the Central African Republic

    Science.gov (United States)

    Albouy, J.; Godivier, R. (Principal Investigator)

    1982-01-01

    Gravimetric maps of the Central African Republic are described including a map of Bouguer anomalies at 1/1,000,000 in two sections (eastern sheet, western sheet) and a map, in color, of Bouguer anomalies at 1/2,000,000. Instrumentation, data acquisition, calibration, and data correction procedures are discussed.

  12. OECD Reviews of School Resources: Slovak Republic

    Science.gov (United States)

    Santiago, Paulo; Halász, Gábor; Levacic, Rosalind; Shewbridge, Claire

    2016-01-01

    This report for the Slovak Republic forms part of the OECD Review of Policies to Improve the Effectiveness of Resource Use in Schools. The purpose of the Review is to explore how school resources can be governed, distributed, utilised and managed to improve the quality, equity and efficiency of school education. School resources are understood in…

  13. Higher Education Reforms in the Slovak Republic.

    Science.gov (United States)

    Pisut, Jan

    1993-01-01

    Early steps in the higher education reform process in the Slovak Republic since 1989 are outlined, difficulties are noted, and suggestions for possible forms of encouragement are listed. Suggestions focus on international cooperation, particularly within the European Community, interinstitutional collaboration, and internal reforms in governance,…

  14. Grey Literature in the Czech Republic

    OpenAIRE

    Pejšová, Petra; Pfeiferová, Martina

    2008-01-01

    Contribution summarizes activities concerning grey literature in the Czech Republic. Contribution describes relationships between systems/projects collecting grey literature and position grey literature in the Czech Digital Library. Contribution is especially focused on a project “The Digital Library for Grey Literature –Functional Model and Pilot Implementation”, which solves the State Technical Library.

  15. Doing Business Economy Profile 2015 : Czech Republic

    OpenAIRE

    2014-01-01

    This economy profile for Doing Business 2015 presents the 11 Doing Business indicators for the Czech Republic. To allow for useful comparison, the profile also provides data for other selected economies (comparator economies) for each indicator. Doing Business 2015 is the 12th edition in a series of annual reports measuring the regulations that enhance business activity and those that cons...

  16. Organic food market in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Iva Živělová

    2013-01-01

    Full Text Available The contribution provides partial results of the research focused on organic food, a product from organic farming. The total area of ecologically farmed areas in the Czech Republic permanently increases, however the offer of organic food is insufficient, in particular in view of their structure. Deficiency in organic food is being solved by imports. Distributors play an important role in the organic food market. In the Czech Republic the largest share from them is occupied by retail chains. Their share continues to grow to the detriment of other sales channels. One of the main factors affecting consumers’ interest in organic food is its price. The comparison of organic food prices and prices of conventional food in the selected retail chains, Globus Czech Republic, limited partnership, SPAR Czech business company Pte., Tesco Stores CZ JSC, AHOLD Czech Republic JSC, BILLA Pte., and in organic food and healthy nutrition stores showed significantly higher prices. The smallest difference in prices can be monitored in the milk and milk products. On the contrary, the largest difference is in fruits, vegetables, eggs and jams. However, the consumers’ awareness of organic food quality is at the same time increasing and the consumers are willing to pay for them a higher price.

  17. Study on the molecular basis of glucoamylase overproduc-tion of a mutant strain Aspergillus niger T21

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The molecular basis for increasing of the glucoamylase (GLA) production of an Aspergillus niger mutant T21 was investigated . Northern blot analysis showed that the amount of glaA specific mRNA of A . niger T21 was about 20 times higher than that of its start strain A . niger AS 3.795. The two glaA promoter fusions (PglaA)-uidAs were respectively introduced into A . niger. Analysis of GUS activity of the transformants revealed that the PglaA activity of the strain T21 is about 3 times stronger than that of the strain AS 3.795. It is considered to be one of the reasons for the increase of glaA transcriptional level in the strain T21. However, comparing with the 20 times increase in the amount of glaA mRNA the alteration of trans regulation should be the most important reason for that. The results of deletion analysis of 5′-cis region of A . niger T21 glaA gene indicated that the region from - 408 to - 513 bp upstream of ATG is responsible for the high level expression of glaA.

  18. Synergistic effect of Aspergillus niger and Trichoderma reesei enzyme sets on the saccharification of wheat straw and sugarcane bagasse.

    Science.gov (United States)

    van den Brink, Joost; Maitan-Alfenas, Gabriela Piccolo; Zou, Gen; Wang, Chengshu; Zhou, Zhihua; Guimarães, Valéria Monteze; de Vries, Ronald P

    2014-10-01

    Plant-degrading enzymes can be produced by fungi on abundantly available low-cost plant biomass. However, enzymes sets after growth on complex substrates need to be better understood, especially with emphasis on differences between fungal species and the influence of inhibitory compounds in plant substrates, such as monosaccharides. In this study, Aspergillus niger and Trichoderma reesei were evaluated for the production of enzyme sets after growth on two "second generation" substrates: wheat straw (WS) and sugarcane bagasse (SCB). A. niger and T. reesei produced different sets of (hemi-)cellulolytic enzymes after growth on WS and SCB. This was reflected in an overall strong synergistic effect in releasing sugars during saccharification using A. niger and T. reesei enzyme sets. T. reesei produced less hydrolytic enzymes after growth on non-washed SCB. The sensitivity to non-washed plant substrates was not reduced by using CreA/Cre1 mutants of T. reesei and A. niger with a defective carbon catabolite repression. The importance of removing monosaccharides for producing enzymes was further underlined by the decrease in hydrolytic activities with increased glucose concentrations in WS media. This study showed the importance of removing monosaccharides from the enzyme production media and combining T. reesei and A. niger enzyme sets to improve plant biomass saccharification.

  19. Removal of heavy metals from contaminated sewage sludge using Aspergillus niger fermented raw liquid from pineapple wastes.

    Science.gov (United States)

    Del Mundo Dacera, Dominica; Babel, Sandhya

    2008-04-01

    The environmental benefits derived from using citric acid in the removal of heavy metals from contaminated sewage sludge have made it promising as an extracting agent in the chemical extraction process. At present, citric acid is produced commercially by fermentation of sucrose using mutant strains of Aspergillus niger (A. niger), and chemical synthesis. In recent years, various carbohydrates and wastes (such as pineapple wastes) have been considered experimentally, to produce citric acid by A. niger. This study investigated the potential of using A. niger fermented raw liquid from pineapple wastes as a source of citric acid, in extracting chromium (Cr), copper (Cu), lead (Pb), nickel (Ni) and zinc (Zn) from anaerobically digested sewage sludge. Results of the study revealed that metal removal efficiencies varied with pH, forms of metals in sludge and contact time. At pH approaching 4, and contact time of 11 days, A. niger fermented liquid seemed to remove all Cr and Zn while removing 94% of Ni. Moreover, chemical speciation studies revealed that metals which are predominantly in the exchangeable and oxidizable phases seemed to exhibit ease of leachability (e.g., Zn). The by-products of the process such as pineapple pulp and mycelium which are rich in protein, can still be used as animal feed. It can be said therefore that this novel process provides a sustainable way of managing contaminated sewage sludge.

  20. Vertical electrical sounding to delineate the potential aquifer zones for drinking water in Niamey city, Niger, Africa

    Indian Academy of Sciences (India)

    Joy Choudhury; K Lohith Kumar; E Nagaiah; S Sonkamble; Shakeel Ahmed; Venay Kumar

    2017-08-01

    Niger is a landlocked African country and the only source of surface water is the Niger River which flows in the western part of Niger and only few villages near to the river gets benefited from it, leaving most of the areas dependent on groundwater solely. The groundwater resources in Niger are mainly used for drinking, livestock and domestic needs. It can be observed that the water exploitation is minimal there due to several factors like undeveloped areas, less population, limited wells, rain-fed irrigation, etc. The delineation of potential aquifer zones is an important aspect for groundwater prospecting. Hence, the direct current (DC) resistivity soundings method also known as vertical electrical sounding (VES) is one of the most applied geophysical techniques for groundwater prospecting that was used in the capital city, Niamey of Niger. Twelve VES surveys, each of AB spacing 400 m were carried out in lateritic and granitic rock formations with a view to study the layer response and to delineate the potential zones. Potential aquifer zones were at shallow depth ranging from 10 to 25 m for the drilled borehole depth of 80–85 m in every village. Analysis of the result showed a good correlation between the acquired data and the lithologs.

  1. Vertical electrical sounding to delineate the potential aquifer zones for drinking water in Niamey city, Niger, Africa

    Science.gov (United States)

    Choudhury, Joy; Kumar, K. Lohith; Nagaiah, E.; Sonkamble, S.; Ahmed, Shakeel; Kumar, Venay

    2017-08-01

    Niger is a landlocked African country and the only source of surface water is the Niger River which flows in the western part of Niger and only few villages near to the river gets benefited from it, leaving most of the areas dependent on groundwater solely. The groundwater resources in Niger are mainly used for drinking, livestock and domestic needs. It can be observed that the water exploitation is minimal there due to several factors like undeveloped areas, less population, limited wells, rain-fed irrigation, etc. The delineation of potential aquifer zones is an important aspect for groundwater prospecting. Hence, the direct current (DC) resistivity soundings method also known as vertical electrical sounding (VES) is one of the most applied geophysical techniques for groundwater prospecting that was used in the capital city, Niamey of Niger. Twelve VES surveys, each of AB spacing 400 m were carried out in lateritic and granitic rock formations with a view to study the layer response and to delineate the potential zones. Potential aquifer zones were at shallow depth ranging from 10 to 25 m for the drilled borehole depth of 80-85 m in every village. Analysis of the result showed a good correlation between the acquired data and the lithologs.

  2. Religious Freedoms In Republic Of Macedonia

    Directory of Open Access Journals (Sweden)

    Metaj-Stojanova Albana

    2015-12-01

    Full Text Available With the independence of Republic of Macedonia and the adoption of the Constitution of Macedonia, the country went through a substantial socio-political transition. The concept of human rights and freedoms, such as religious freedoms in the Macedonian Constitution is based on liberal democratic values. The Macedonian Constitution connects the fundamental human rights and freedoms with the concept of the individual and citizen, but also with the collective rights of ethnic minorities, respecting the international standards and responsibilities taken under numerous international human rights conventions and treaties, of which the country is a party. Republic of Macedonia has ratified all the so called “core human right treaties” and now the real challenge lies in the implementation of the international standards. Some of these international conventions and treaties of the United Nations and of the Council of Europe are inherited by succession from the former Yugoslavian federation. Religious freedoms are guaranteed by the Universal Declaration of human rights (1948, the International Covenant on Civil and Political Rights (1966, the European Convention on Human Rights (1953, the Declaration on the Elimination of All Forms of Intolerance and of Discrimination Based on Religion or Belief (1981 (all documents ratified by the Republic of Macedonia. According to the Constitution of the Republic of Macedonia “The freedom of religious confession is guaranteed. The right to express one's faith freely and publicly, individually or with others, is guaranteed„. After the conflict of 2001 the Ohrid Framework Agreement secured group rights for ethnicities that are not in majority in the Republic of Macedonia. The present Law on the legal status of the church, religious communities and religious groups of 2007, repealed the Law on religion and religious groups of 1997.

  3. [Synthetic mineral fibers].

    Science.gov (United States)

    Boillat, M A

    1999-03-27

    The group of man-made mineral fibres includes slagwool, glasswool, rockwool, glass filaments and microfibres, as well as refractory ceramic fibres. The toxicity of mineral fibres is determined by several factors such as the diameter (ceramic fibres. A slightly elevated standard mortality ratio for lung cancer has been documented in large cohorts of workers (USA, Europe and Canada) exposed to man-made mineral fibres, especially in the early technological phase. It is not possible to determine from these data whether the risk of lung cancer is due to the man-made mineral fibres themselves, in particular due to the lack of data on smoking habits. No increased risk of mesothelioma has been demonstrated in these cohorts. Epidemiological data are insufficient at this time concerning neoplastic diseases in refractory ceramic fibres.

  4. Minerals in environmental technology

    Energy Technology Data Exchange (ETDEWEB)

    Schuiling, R.D. [Utrecht Univ., Utrecht (Netherlands). Faculty of Earth Sciences

    2000-07-01

    Minerals play a key role in the environment; this role is often not well understood, because the emphasis of most environmentalists is on air, water, or the composition of solid wastes as a whole, without paying attention to their mineralogical composition. Several minerals can serve as effective and cheap adsorbents for many toxic chemicals. Several minerals can be used as a cheap substitute for expensive chemicals in environmental technologies. Environmental technologies that produce an economically interesting mineral will have an edge over competing technologies. Most of the problems, overreaction, panicky and expensive measures with regard to exposure from quartz and asbestos stem from a poor understanding of natural levels of common contaminants, a disregard for mineralogy, and a lack of insight into natural processes in general.

  5. sequenceMiner algorithm

    Data.gov (United States)

    National Aeronautics and Space Administration — Detecting and describing anomalies in large repositories of discrete symbol sequences. sequenceMiner has been open-sourced! Download the file below to try it out....

  6. Vitamins and Minerals

    Science.gov (United States)

    ... minerals your body needs. But if you're skipping meals, dieting, or if you're concerned that ... Kids For Parents MORE ON THIS TOPIC Healthy Breakfast Planner Nutrition & Fitness Center Vitamin D Figuring Out ...

  7. Βedrock instability of underground storage systems in the Czech Republic, Central Europe

    Science.gov (United States)

    Novakova, Lucie; Broz, Milan; Zaruba, Jiri; Sosna, Karel; Najser, Jan; Rukavickova, Lenka; Franek, Jan; Rudajev, Vladimir

    2016-06-01

    Underground storage systems are currently being used worldwide for the geological storage of natural gas (CH4), the geological disposal of CO2, in geothermal energy, or radioactive waste disposal. We introduce a complex approach to the risks posed by induced bedrock instabilities in deep geological underground storage sites. Bedrock instability owing to underground openings has been studied and discussed for many years. The Bohemian Massif in the Czech Republic (Central Europe) is geologically and tectonically complex. However, this setting is ideal for learning about the instability state of rock masses. Longterm geological and mining studies, natural and induced seismicity, radon emanations, and granite properties as potential storage sites for disposal of radioactive waste in the Czech Republic have provided useful information. In addition, the Czech Republic, with an average concentration radon of 140 Bq m-3, has the highest average radon concentrations in the world. Bedrock instabilities might emerge from microscale features, such as grain size and mineral orientation, and microfracturing. Any underground storage facility construction has to consider the stored substance and the geological settings. In the Czech Republic, granites and granitoids are the best underground storage sites. Microcrack networks and migration properties are rock specific and vary considerably. Moreover, the matrix porosity also affects the mechanical properties of the rocks. Any underground storage site has to be selected carefully. The authors suggest to study the complex set of parameters from micro to macroscale for a particular place and type of rock to ensure that the storage remains safe and stable during construction, operation, and after closure.

  8. Background Report on Eastern Democratic Republic of the Congo

    Energy Technology Data Exchange (ETDEWEB)

    Warren, Tracy A [ORNL

    2011-05-01

    Each month, approximately 45,000 people die from violence, hunger, disease, and other effects of displacement as a result of war in the Democratic Republic of the Congo (DRC). The country is often said to be plagued by a 'resource curse.' During each period in history since its discovery by the West, the DRC has possessed the resources the world craves and the world has sought these without regard for the consequences to the Congolese people. The catastrophic consequences of Congo's history of natural resource exploitation are the direct and indirect death of millions of Congolese people. The current war in Congo is multi-causal in nature but explanations are often reduced to describing it as an ethic conflict based on objective grievance. Objective grievance such as inequality, ethnic tensions, land disputes, and lack of democracy do exist, but they are neither necessary nor sufficient to explain the cause of the violent conflict, and more importantly, they fall short in explaining why this conflict has continued for years. The reality is the conflict is an economic war in which the trade of conflict minerals, gold and the 3Ts (tin, tantalum, tungsten), is directly linked to the financial sustainability of the groups fighting each other in eastern DRC. Objective grievance is a by-product of the conflict, used to create a false but plausible moral justification to continue violence. This paper examines the history of conflict in the DRC and the socio-economic variables contributing to the current war fought over conflict minerals.

  9. The analysis of the state of foreign trade in the republic of Tuva on the 2011-2015 time period

    Directory of Open Access Journals (Sweden)

    Aygul M. Oorzhak

    2016-12-01

    Full Text Available The article examines one of the most important topics in socioeconomic development of the Republic of Tuva — the region’s foreign trade. There is a marked lack of research on the current foreign trade turnover of Tuva. We used statistical data provided by the Agency for Foreign Economic Relations of the Republic of Tuva and the Siberian Customs Directorate of Federal Customs Service to analyze the foreign trade turnover and commodity structure of exports and imports for the years 2011-2015. The statistical data are presented in charts, showing the dynamics of the trends observed. In Tuva, imports exceed exports, with the main articles of export being minerals and foodstuffs, and those of import, machinery, equipment and vehicles. Despite the fact that the Republic of Tuva is a border region, its foreign trade is the smallest in the Siberian Federal district. In foreign trade turnover per capita (the indicator used by the World Bank to measure the openness of the global market, the economy of the Republic of Tuva is relatively closed. The factors hindering the development of foreign trade include the absence of railways and a small number of enterprises exporting competitive goods.

  10. Academic Science and New Industrialization (on the Republic of Komi Example

    Directory of Open Access Journals (Sweden)

    Vitaly Nikolayevich Lazhentsev

    2016-12-01

    Full Text Available Currently, the achievements of science and technological progress define in a greater degree new reference points of the strategic planning for national and regional development are d by. The results of research and development which are noteworthy from the point of view of the improvement of scientific, technological, socio- economic processes in northern and Arctic territories (in our case — the Republic of Komi, as a rule, take the form of interdisciplinary projects. These projects generate the results of research on the social and economic, humanitarian and medical- biological problems; conservation of biosphere and ecosystems with simultaneous development of bioresource economics; management of mineral-raw, fuel and energy resources; spatial development; creation and use of innovative technologies. The key idea of the paper is the realization of new industrialization of the Republic of Komi taking into account the results of the research works carried out at the institutes of the Komi Scientific Centre of the Ural Branch of the Russian Academy of Sciences. The applied research of the institutes of the Komi Scientific Centre is based on fundamental studies and is closely connected with the practice of the development and location of production. They are oriented at the realization of a new paradigm of the northern policy which consists not only in the development of mineral-raw and power resources for external consumers, but also in the arrangement, sustainable development and creation of appropriate conditions for the life of the population settled down in the North. Special attention is paid to the reproduction of human and natural resource potentials. The sectoral structure of the economy of the republic, as well as of the majority of other northern and Arctic regions, will not change drastically in the long term,, but the internal content of productive forces will be different. It will correspond to the concept of resource

  11. Flotation of cobalt bearing minerals from a mixed copper-cobalt oxidized ore

    OpenAIRE

    2012-01-01

    M.Tech. (Extraction Metallurgy) The techniques for the flotation of mixed copper and cobalt bearing oxide ores using the sulphidization method in order to recover the oxidized copper and cobalt bearing minerals have been well documented by previous researchers. These processes have been successfully implemented in many of the metallurgical plant operations in the Democratic Republic of Congo (DRC). The mixed copper and cobalt oxidised ores from this region present significant chal-lenges t...

  12. Proteome analysis of Aspergillus niger: Lactate added in starch-containing medium can increase production of the mycotoxin fumonisin B2 by modifying acetyl-CoA metabolism

    DEFF Research Database (Denmark)

    Sørensen, Louise Marie; Lametsch, Rene; Andersen, Mikael Rørdam

    2009-01-01

    Background Aspergillus niger is a filamentous fungus found in the environment, on foods and feeds and is used as host for production of organic acids, enzymes and proteins. The mycotoxin fumonisin B2 was recently found to be produced by A. niger and hence very little is known about production...

  13. AFM images of complexes between amylose and Aspergillus niger glucoamylase mutants, native and mutant starch binding domains: a model for the action of glucoamylase

    DEFF Research Database (Denmark)

    Morris, V. M.; Gunning, A. P.; Faults, C. B.

    2005-01-01

    Atomic force microscopy has been used to investigate the complexes formed between high molecular weight amylose chains and Aspergillus niger glucoamylase mutants (E400Q and W52F), wild-type A. niger starch binding domains (SBDS), and mutant SBDs (W563K and W590K) lacking either of the two starch ...

  14. OPTIMIZATION OF MILK-CLOTTING PROTEASE PRODUCTION BY A LOCAL ISOLATE OF ASPERGILLUS NIGER FFB1 IN SOLID-STATE FERMENTATION

    Directory of Open Access Journals (Sweden)

    Souhila Bensmail

    2015-04-01

    Full Text Available The need to surmount the limitation of obtaining rennin, has been actively pushed researches to find new substitutes that present high milk-clotting activity which enables the production of high yields of cheese. In this study, the production of extracellular milk-clotting protease by locally isolated fungal specie, Aspergillus niger FFB1 under solid-state fermentation (SSF using cheep agro-industrial byproduct (wheat bran was optimized. The effects of several physicochemical and environmental factors were investigated to select the optimal conditions that ensure the best milk-clotting activity by application of "One-factor-at-a-time" method. A trial of cheese production using the crude extract was also carried out. The maximum enzyme activity (830 SU/g bran with a ratio MCA/PA of 4.25 was obtained under the optimum conditions of temperature (30°C, spores concentration (106 spores/mL, incubation time (72 hours, and moisture content of solid substrate (39.2% adjusted suitably with mineral solution (Czapek-Dox of pH 4.

  15. Mathematical model for bone mineralization

    Directory of Open Access Journals (Sweden)

    Svetlana V Komarova

    2015-08-01

    Full Text Available Defective bone mineralization has serious clinical manifestations, including deformities and fractures, but the regulation of this extracellular process is not fully understood. We have developed a mathematical model consisting of ordinary differential equations that describe collagen maturation, production and degradation of inhibitors, and mineral nucleation and growth. We examined the roles of individual processes in generating normal and abnormal mineralization patterns characterized using two outcome measures: mineralization lag time and degree of mineralization. Model parameters describing the formation of hydroxyapatite mineral on the nucleating centers most potently affected the degree of mineralization, while the parameters describing inhibitor homeostasis most effectively changed the mineralization lag time. Of interest, a parameter describing the rate of matrix maturation emerged as being capable of counter-intuitively increasing both the mineralization lag time and the degree of mineralization. We validated the accuracy of model predictions using known diseases of bone mineralization such as osteogenesis imperfecta and X-linked hypophosphatemia. The model successfully describes the highly non-linear mineralization dynamics, which includes an initial lag phase when osteoid is present but no mineralization is evident, then fast primary mineralization, followed by secondary mineralization characterized by a continuous slow increase in bone mineral content. The developed model can potentially predict the function for a mutated protein based on the histology of pathologic bone samples from mineralization disorders of unknown etiology.

  16. Aspergillus niger F-01和Aspergillus niger G-1125生淀粉酶糖化酶基因启动子的克隆与比较分析

    Institute of Scientific and Technical Information of China (English)

    孙海彦; 黎娟华; 刘恩世; 易小平; 杨景豪; 彭明

    2015-01-01

    从生淀粉低产菌Aspergillus niger F-01和高产菌Aspergillus niger G-1125中克隆到生淀粉糖化酶的启动序列,这两个菌种生淀粉糖化酶基因启动子序列长分别是651bp和613bp,两个启动子都含有真核生物启动子的典型序列CCAAT和TATAAAT,通过序列比对发现,这两个启动子的同源性为84.4%。

  17. Aspergillus niger F-01和Aspergillus niger G-1125生淀粉酶糖化酶基因启动子的克隆与比较分析

    Institute of Scientific and Technical Information of China (English)

    孙海彦; 黎娟华; 刘恩世; 易小平; 杨景豪; 彭明

    2015-01-01

    从生淀粉低产菌Aspergillus niger F-01和高产菌Aspergillus niger G-1125中克隆到生淀粉糖化酶的启动序列,这两个菌种生淀粉糖化酶基因启动子序列长分别是651bp和613bp,两个启动子都含有真核生物启动子的典型序列CCAAT和TATA-AAT,通过序列比对发现,这两个启动子的同源性为84.4%.

  18. Community responses of intertidal soft-bottom macrozoobenthos to oil pollution in a tropical mangrove ecosystem, Niger Delta, Nigeria.

    Science.gov (United States)

    Zabbey, Nenibarini; Uyi, Hanson

    2014-05-15

    Preliminary impact assessment of two large oil spill incidents at Bodo Creek, in the Niger Delta, was undertaken, focusing on intertidal macrozoobenthos. Post-spill number of species and abundance were measured against recent pre-spill baseline data from the same study area. Results show that surface and infauna communities suffered severe reduction in abundance and number of species reduced by 81% after the spills, with two of the resampled sites having no taxa at all. Capitella capitata populations increased several-fold over pre-spill numbers. The impact of the oil spills is discussed in relation to local livelihoods and ecosystem integrity. The Niger Delta endemic lucinid, Keletistes rhizoecus, is proposed as a potential bioindicator for monitoring hydrocarbon contamination in Niger Delta estuaries.

  19. Sedimentology and ichnology of Neogene Coastal Swamp deposits in the Niger Delta Basin, Nigeria

    Science.gov (United States)

    Ezeh, Sunny C.; Mode, Wilfred A.; Ozumba, Berti M.; Yelwa, Nura A.

    2016-09-01

    Often analyses of depositional environments from sparse data result in poor interpretation, especially in multipartite depositional settings such as the Niger Delta. For instance, differentiating channel sandstones, heteroliths and mudstones within proximal environments from those of distal facies is difficult if interpretations rely solely on well log signatures. Therefore, in order to achieve an effective and efficient interpretation of the depositional conditions of a given unit, integrated tools must be applied such as matching core descriptions with wireline log signature. In the present paper cores of three wells from the Coastal Swamp depositional belt of the Niger Delta are examined in order to achieve full understanding of the depositional environments. The well sections comprise cross-bedded sandstones, heteroliths (coastal and lower shoreface) and mudstones that were laid down in wave, river and tidal processes. Interpretations were made from each data set comprising gamma ray logs, described sedimentological cores showing sedimentary features and ichnological characteristics; these were integrated to define the depositional settings. Some portions from one of the well sections reveal a blocky gamma ray well log signature instead of a coarsening-upward trend that characterises a shoreface setting while in other wells the signatures for heteroliths at some sections are bell blocky in shaped rather than serrated. Besides, heteroliths and mudstones within the proximal facies and those of distal facies were difficult to distinguish solely on well log signatures. However, interpretation based on sedimentology and ichnology of cores from these facies was used to correct these inconsistencies. It follows that depositional environment interpretation (especially in multifarious depositional environments such as the Niger Delta) should ideally be made together with other raw data for accuracy and those based solely on well log signatures should be treated with

  20. The Koundoum sheep breed in Niger: morpho-biometric study and description of the production system

    Directory of Open Access Journals (Sweden)

    Issa Hamadou

    2015-05-01

    Full Text Available The diffusion of highly productive breeds across developing countries goes along with a neglect of indigenous breeds, which are well suited to their environment but often show low yields. Thus, in Niger, the flock of Koundoum sheep are rapidly decreasing. The Koundoum is one of the few wool sheep breeds of Africa and shows important adaptive feature to its native environment, i.e. the humid pastures on the banks of the Niger River. To characterise the breed and to understand its production context, a survey has been conducted in 104 herds in four communes along the Niger River (Kollo, Tillabery, Say and Tera. Nine body measurements, including live weight, were taken on 180 adult sheep (101 females and 79 males. The herds varied from 2 to 60 heads, with a median size of eight animals and two thirds of the herds having less than 10 animals. Mainly fed on natural pastures, 85.6% of the herds received crop residues. Only natural mating was practiced. Veterinary care was restricted to anti-helminthic and some indigenous treatments. The frequent affiliation of breeders to professional unions appeared as favourable to the implementation of a collective conservation program. The Koundoum sheep were white or black coated, with the black colour being most frequent (75.6 %. Wattles were present in both sexes at similar frequencies of around 14 %. All biometric variables were significantly and positively correlated between them. The thoracic perimeter showed the best correlation with live weight in both males and females. Three variables were selected for live weight prediction: thoracic perimeter, height at withers and rump length. From the present study, it is expected that the in situ conservation of the Koundoum sheep will be highly problematic, due to lack of market opportunities for wool and the willingness of smallholders to get involved in pure Koundoum rearing.