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641.
Arthrobacter sp. HPC1223 (Genebank Accession No. AY948280) isolated from activated biomass of effluent treatment plant was capable of utilizing 2,4,6 trinitrophenol (TNP) under aerobic condition at 30 °C and pH 7 as nitrogen source. It was observed that the isolated bacteria utilized TNP up to 70 % (1 mM) in R2A media with nitrite release. The culture growth media changed into orange-red color hydride-meisenheimer complex at 24 h as detected by HPLC. Oxygen uptake of Arthrobacter HPC1223 towards various nitro/amino substituted phenols such as dinitrophenol (1.2 nmol/min/mg cells), paranitrophenol (0.9 nmol/min/mg cells), 2-aminophenol (0.75 nmol/min/mg cells), p-aminophenol (0.4 nmol/min/mg cells), phenol (0.56 nmol/min/mg cells) and TNP (2.42 nmol/min/mg cell) was analysed, which showed its additional characteristic of broad substrate catabolic capacity. The present study thus report a novel indigenous bacteria isolated from activated sludge utilized TNP and has broad catabolic potential towards substituted phenols. 相似文献
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Zahir Qureshi Lauren M. Cagen 《Biochemical and biophysical research communications》1982,104(4):1255-1263
Slices of rabbit renal medulla and rabbit renal papilla were incubated with a mixture of [1-14C]-arachidonic acid and [5,6,8,9,11,12,14,15-3H]-arachidonic acid. In both tissues, comparison of the isotope ratios of the radioactive products with the isotope ratio of the added arachidonic indicated that: (a) there was no discernable isotope effect in the biosynthesis of prostaglandin E2; (b) prostaglandin F2α was formed by reduction of prostaglandin H2 and not by reduction of prostaglandin E2; and (c) most of the radioactive product arose from arachidonic acid that had been incorporated into the tissue and not from the direct action of cyclooxygenase on arachidonic acid in the medium. 相似文献
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Cells of Clostridium acetobutylicum were immobilized by adsorption onto bonechar. and used for the production of solvents (ABE fermentation) from whey permeate. When the process was performed in packed bed reactors operated in a vertical or inclined mode, solvent productivities approximating 6 kg/(m3h) were obtained. However, the systems suffered from blockage due to excess biomass production and gas hold-up. These problems were less apparent when a partially-packed bed reactor was operated in the horizontal mode. A fluidized bed reactor proved to be the most stable of the systems investigated, and a productivity of 4.8 kg/(m3h) was maintained over a period of 2000 h of operation. The results demonstrate that this type of reactor may have a useful future role in the ABE fermentation. 相似文献
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Tawqir Bashir Tapajit Bhattacharya Kamal Poudyal Sambandam Sathyakumar Qamar Qureshi 《Acta theriologica》2014,59(1):35-47
An understanding of species ecology is vital for effective conservation, particularly if the species forms an important constituent of the lesser mammal guild and regulates small mammal and bird populations. As the ecological role of the leopard cat (Prionailurus bengalensis) in the intricate eastern Himalayan habitats is not known, we assessed the site occupancy, detection probability and activity pattern of leopard cats in Khangchendzonga Biosphere Reserve, India, based on sign surveys and camera trapping. The estimated site occupancy was 0.352?±?0.061 and detection probability was 0.143?±?0.0484. Occupancy modelling indicated low elevation, high rodent abundance and tree cover as best predictors for the occupancy of leopard cat. Diet based on analysed scats revealed murids as the most dominant prey (89.2 %). Information based on photographic captures indicated that the leopard cat exhibited a nocturnal activity pattern (peak activity between 0200–0300 hours), which coincided with its principal prey (revealed through diet analysis), but mainly contradicted with other sympatric competitors, hence indicating a temporal partitioning of resources among them. Ecological niche factor analysis indicated that the leopard cat exhibits high global marginality (1.32) and low global tolerance (0.275). The habitat suitability map for leopard cats showed majority of the habitat as unsuitable (1,959.44 km2) and predicted only 164.54 km2 areas of lower temperate forests as moderate to highly suitable. As highly suitable habitats of the leopard cat are in close proximity to villages, conflict issues are a major threat and therefore need to be addressed in conservation program for this felid. 相似文献