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191.
Annapurna Kumari Paramita Mahapatra Vijay Kumar Garlapati Rintu Banerjee 《Biotechnology for biofuels》2009,2(1):1-7
Background
Transesterification of Jatropha oil was carried out in t-butanol solvent using immobilized lipase from Enterobacter aerogenes. The presence of t-butanol significantly reduced the negative effects caused by both methanol and glycerol. The effects of various reaction parameters on transesterification of Jatropha oil were studied. 相似文献192.
193.
194.
R. Kumari P. Seth M. Dikshit 《Redox report : communications in free radical research》2013,18(3):191-195
SUMMARYAn involvement of free radicals in thrombosis has been suggested previously. In order to further explore the role of free radicals and antioxidants in thrombosis, we have measured preventive (enzymes of the glutathione redox cycle) and chain-breaking antioxidants (vitamin E and C) in whole blood, platelets, neutrophils (PMNLs), heart and lung following collagen and adrenaline induced thrombosis in mice. A significant decrease in platelet glutathione (GSH) level (54%) and glutathione reductase activity was observed after thrombosis. In addition, GSH content in whole blood was also found to be reduced. In PMNLs, an increase in glutathione peroxidase activity and a four-fold elevation in vitamin C content was observed following thrombosis. However, levels of vitamin E and total thiol groups remained unchanged in both the cells and tissues. The results further suggest involvement of free radicals and PMNLs in thrombosis. 相似文献
195.
It is well reported that the environmental factors along with different endocrine stimulus play a crucial role in maintenance of adrenocortical activity in birds. This study is first to report a detailed seasonal activity cycle of adrenal cortex, particu-larly its secretory physiology in a tropical nocturnal bird, Indian spotted owlet Athene brama. The maximum cortical activity having highest glandular mass, glandular free cholesterol, esterified cholesterol profiles, and peak level of corticosterone in plasma coincided with the long day length, highest temperature and increasing amplitude of relative humidity and rainfall of the early summer month, May. Cortical activity declined to minimum level in August when the ecofactors also declined parallely and hence, the birds entered into partial hibernation. The cortical activity progressed slowly throughout the winter (September–March) to reach maximum level in May. Further, the electron microscopic observations of cortical cell morphology strongly supported the above seasonal activity status of the gland revealing a comparatively large number of mitochondria during May than August, along with lipid filled vacuoles during May but not in August. Besides, assessment of gonadal and pineal hormones in relation with seasonal activity of adrenal cortex presented a parallel relationship with gonad while completely inverse relationship with pineal. Therefore, the study concludes that the seasonal adrenocortical activity of this tropical nocturnal bird might be regulated by multiple factors, particularly by the environmental temperature, humidity/rainfall and photoperiod along with the internal factors at least by gonadal and pineal hormones. 相似文献
196.
Amrita Kumari Panda Satpal Singh Bisht Surajit DeMondal N. Senthil Kumar G. Gurusubramanian Ashok Kumar Panigrahi 《Antonie van Leeuwenhoek》2014,105(4):623-639
The significance of Brevibacillus has been documented scientifically in the published literature and commercially in heterologous recombinant protein catalogs. Brevibacillus is one of the most widespread genera of Gram-positive bacteria, recorded from the diverse environmental habitats. The high growth rate, better transformation efficiency by electroporation, availability of shuttle vectors, production of negligible amount of extracellular protease, and the constitutive expression of heterologous proteins make some strains of this genus excellent laboratory models. Regarding biotechnological applications, this genus continues to be a source of various enzymes of great biotechnological interest due to their ability to biodegrade low density polyethylene, ability to act as a candidate bio-control agent, and more recently acknowledged as a tool for the overexpression. This article reviews the properties of Brevibacillus spp. as better biological tools with varied applications. 相似文献
197.
Arti Vasudev Talwinder Kaur Rajesh Kumari Manhas 《Archives Of Phytopathology And Plant Protection》2013,46(9-12):720-739
Proteinaceous extract obtained from Cassia occidentalis seeds with purification fold of 3.91 and 82.7% of bovine trypsin inhibitory activity was assessed at different concentrations (25, 50, 100, 200, 400 and 800 μg/ml) against Spodoptera litura. Assay of larval feeding suggested proteinaceous extract to be toxic as prepupal (80.16%) and pupal mortalities (100%) along with growth deterrent effect with only 16.71% pupation was observed at 800 μg/ml. Fifty per cent mortality (LC50) was observed at 132.91 μg/ml. Also the inhibitor affected fecundity, longevity and percentage of egg hatching. Nutritional indices were adversely affected as both efficiency of conversion of ingested and digested food decreased while approximate digestibility and metabolic cost increased. In vitro studies on proteolytic enzymes of S. litura revealed inhibition of trypsin and chymotrypsin in lumen and faecal matter at all tested concentrations. Also proteinaceous extract inhibited mycelial growth in Fusarium oxysporum, Alternaria brassicicola and Alternaria alternata at 100 μg/ml. 相似文献
198.
The pituitary gland of Puntius sarana is of the leptobasic type and has three subdivisions--a proximal pars distalis (PPD), a rostral pars distalis (RPD) and a pars intermedia (PI) arranged vertically one below the other. The gonadotrophs (GTH cells) of the PPD were identified by their PAS, ATh, AF, aniline blue and alcian blue positivity and by their immunoreactivity to ovine anti-LH beta-subunit, anti-salmon GTH and anti-silver carp GTH. The testes of Puntius sarana have been classified as the "unrestricted type". The morphological, histological and histometric findings indicate that the testing passes through four distinct stages--preparatory, fully mature, spawning and spent. Spermatogenesis begins in January and continues up to July. The spawning season lasts from late July until October. Cyclical changes in the gonadotrophs correlate well with changes in the testes. The histometric data show that the GTH cells attain maximum values (size and number) during the breeding season. The peak values for testicular weight, lobule diameter, the gonadosomatic index (GSI) and the sperm concentration in the testes, and the number, size and amount of secretory material in the cytoplasm of the gonadotrophs, coincide with the time of maximum environmental temperature and the longest days. 相似文献
199.
Rearrangement and overexpression of the gene coding for tumor antigen p53 in a rat histiocytoma AK-5
The gene coding for the cellular tumor antigen p53 is rearranged and overexpressed in a rat histiocytoma, AK-5. The protein coded by the gene was detected by immunofluorescence and its full size was confirmed by immunoprecipitation using monoclonal antibodies against p53. Southern hybridizations with a full length cDNA probe specific for p53 indicated rearrangement of the gene. Alterations in the upstream region, which probably disrupt the normal regulatory control are suggested by the pattern obtained using a 5'-specific p53 probe in Southern hybridization. 相似文献
200.
Human alpha fetoprotein (AFP) binds bilirubin with an affinity somewhat lower than albumin. Free bilirubin was found to have an extinction maximum at 440 nm with an extinction coefficient of 4.97 x 10(4) M-1cm-1. AFP binding with the bile pigment elicits a blue shift while albumin interaction produced red spectral shift. 相似文献