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1.
Tapan K. Ghosh Amita Moitra Gopal K. Kunwar Jyoti S. D. Munshi 《Ichthyological Research》1986,33(3):280-285
Measurements of bimodal oxygen uptake have been made in a freshwater air-breathing fish,Notopterus chitala at 29.0±1(S.D.)°C. xhe mean oxygen uptake from continuously flowing water without any access to air, was found to be 3.58±0.37 (S.E.) ml O2 · h?1 and 56.84+4.29 (S.E.) ml O2 · kg?1 · h?1 for a fish weighing 66.92 + 11.27 (S.E.) g body weight. In still water with access to air, the mean oxygen uptake through the gills were recorded to be 2.49 ± 0.31 (S.E.) ml O2 · h?1 and 38.78 ± 1.92 (S.E.) ml O2 · kg?1 · h?1 and through the accessory respiratory organs (swim-bladder) 6.04±0.87 (S.E.) ml O2 · h?1 and 92.32±2.91 (S.E.) ml O2 · kg?1 · h?1 for a fish averaging 66.92±11.27 (S.E.) g. Out of the total oxygen uptake (131.10 ml O2 · kg?1 · h?1), about 70% was obtained through the aerial route and the remainder 30% through the gills. 相似文献
2.
Adsorption of fungal spores on a synthetic polymer - High Density Polyethylene was successfully achieved using different pretreatments. Sonication of beads followed by ferric nitrate treatment or use of 0.1% tributyrin gave adsorption upto 46%. Use of dichloromethane as a solvent for sonication is recommended for its better performance in reuse studies (upto 5 times without much decrease in activity). 100 g of immobilized biocatabyst in a 7 L Fluidized Bed Bioreactor was found to perform better than shaker flask at a much lower power input. 相似文献
3.
H. N. Ravishankar Aparna V. S. Rao T. Ramasarma 《Molecular and cellular biochemistry》1996,154(2):101-106
Sequential addition of vanadyl sulfate to a phosphate-buffered solution of H2O2 released oxygen only after the second batch of vanadyl. Ethanol added to such reaction mixtures progressively decreased oxygen release and increased oxygen consumption during oxidation of vanadyl by H2O2. Inclusion of ethanol after any of the three batches of vanadyl resulted in varying amounts of oxygen consumption, a property also shared by other alcohols (methanol, propanol and octanol). On increasing the concentration of ethanol, vanadyl sulfate or H2O2, both oxygen consumption and acetaldehyde formation increased progressively. Formation of acetaldehyde decreased with increase in the ratio of vanadyl:H2O2 above 2:1 and was undetectable with ethanol at 0.1 mM. The reaction mixture which was acidic in the absence of phosphate buffer (pH 7.0), released oxygen immediately after the first addition of vanadyl and also in presence of ethanol soon after initial rapid consumption of oxygen, with no accompanying acetaldehyde formation. The results underscore the importance of some vanadium complexes formed during vanadyl oxidation in the accompanying oxygen-transfer reactions. 相似文献
4.
Manab Jyoti Goswami Utpal Dutta Tage Seema Sourav Jyoti Bharali Hage Yanka Hui Tag Pankaj Bharali Dwipen Kakati 《化学与生物多样性》2023,20(2):e202200718
Three underutilized leafy vegetables Sarcochlamys pulcherrima (Roxb.) Gaudich (SP), Ipomoea aquatica Forssk. (IA) and Zanthoxylum rhetsa (Roxb.) DC (ZR) were extracted with different solvents viz. 95 % ethyl alcohol, methanol and hot water. The extracts were evaluated for their antioxidant potential via DPPH, ABTS and FRAP assay along with electroanalytical studies using cyclic voltammetry. The antidiabetic potential was determined by recording their α-amylase and α-glucosidase inhibitory assay. The total phenolic content (TPC), total flavonoid content (TFC) and the liquid chromatography-mass spectrometry (LC/MS) based phytochemical profiles of the extracts were also determined. All three extracts of SP exhibited significant antioxidant capacity. The antidiabetic potential of the IA and ZR extracts was found to be higher than or at par with that of standard acarbose. LC/MS studies reveal the presence of hitherto reported antioxidant and antidiabetic compounds like gamma-aminobutyric acid, cinnamic acid, caffeic acid, α-viniferin, piperlonguminine, niacin, kaempferol, etc., in the extracts. 相似文献
5.
6.
Jagdish Ojha Narendra Mishra Mahadeo Prasad Saha Jyoti Swarup Datta Munshi 《Hydrobiologia》1979,63(2):153-159
Oxygen uptake of Channa marulius was studied under water with and without access to air. There was a significant increase in the oxygen uptake through the gills when access to air was prevented. However, this value (0.863 ± 0.058 mlO2/indiv./h) was quite low in comparison to the total bimodal oxygen uptake (2.04 ± 0.14 mlO2/indiv./h) in juveniles. In adult fish the oxygen uptake per unit time increased appreciably (4.673 ± 0.404 mlO2/indiv./h). In juveniles as well as in adults the air breathing dominated over aquatic breathing. This fish showed a definite circadian rhythm in the bimodal oxygen uptake during different hours of the day.This work was performed in the Ichthyology Laboratory, P. G. Dept. of Zoology, Bhagalpur University, and was supported by a research grant from Bhagalpur University 相似文献
7.
Cyclodextrin glucanotransferase (CGTase) from Bacillus circulans (ATCC 21783) was immobilised on a silica-based support: purified seasand. Although adsorption of 98% was achieved, considerable
desorption was encountered. This problem was minimised by crosslinking the adsorbed enzyme with glutaraldehyde. The immobilised
enzyme after crosslinking could be used repeatedly for cyclodextrin (CD) production in a batch process. The activity retention
was 80% at the end of the eighth cycle. The immobilised enzyme showed a shift in the pH optimum towards the alkaline side
and also an improvement in the pH stability compared to the free enzyme. It catalysed the formation of β-CD as a major product.
A significant amount of α-CD production was also observed on prolonged incubation.
Electronic Publication 相似文献
8.
Vema A Panigrahi SK Rambabu G Gopalakrishnan B Sarma JA Desiraju GR 《Bioorganic & medicinal chemistry》2003,11(21):4643-4653
Three-dimensional quantitative structure-activity relationship (3D-QSAR) models were developed for 100 anilinoquinazolines, inhibiting epidermal growth factor receptor (EGFR) kinase. The studies included molecular field analysis (MFA) and receptor surface analysis (RSA). The cross-validated r2 (r2cv) values are 0.81 and 0.79 for MFA and RSA, respectively. The predictive ability of these models was validated by 28 test set molecules. The results of the best QSAR model were further compared with structure-based investigations using docking studies with the crystal structure of EGFR kinase domain. The results helped to understand the nature of substituents at the 6- and 7-positions, thereby providing new guidelines for the design of novel inhibitors. 相似文献
9.
Esperanza Fernández Mark O Collins Rachel T Uren Maksym V Kopanitsa Noboru H Komiyama Mike D R Croning Lysimachos Zografos J Douglas Armstrong Jyoti S Choudhary Seth G N Grant 《Molecular systems biology》2009,5(1)
The molecular complexity of mammalian proteomes demands new methods for mapping the organization of multiprotein complexes. Here, we combine mouse genetics and proteomics to characterize synapse protein complexes and interaction networks. New tandem affinity purification (TAP) tags were fused to the carboxyl terminus of PSD‐95 using gene targeting in mice. Homozygous mice showed no detectable abnormalities in PSD‐95 expression, subcellular localization or synaptic electrophysiological function. Analysis of multiprotein complexes purified under native conditions by mass spectrometry defined known and new interactors: 118 proteins comprising crucial functional components of synapses, including glutamate receptors, K+ channels, scaffolding and signaling proteins, were recovered. Network clustering of protein interactions generated five connected clusters, with two clusters containing all the major ionotropic glutamate receptors and one cluster with voltage‐dependent K+ channels. Annotation of clusters with human disease associations revealed that multiple disorders map to the network, with a significant correlation of schizophrenia within the glutamate receptor clusters. This targeted TAP tagging strategy is generally applicable to mammalian proteomics and systems biology approaches to disease. 相似文献
10.
Prameela?KandraEmail author Hemalatha?Padma Jyoti?Kalangi 《Applied microbiology and biotechnology》2015,99(5):2055-2064
Recent advances have been made in cancer chemotherapy through the development of conjugates for anticancer drugs. Many drugs have problems of poor stability, water insolubility, low selectivity, high toxicity, and side effects. Most of the chitosan nanoparticles showed to be good drug carriers because of their biocompatibility, biodegradability, and it can be readily modified. The anticancer drug with chitosan nanoparticles displays efficient anticancer effects with a decrease in the adverse effects of the original drug due to the predominant distribution into the tumor site and a gradual release of free drug from the conjugate which enhances drug solubility, stability, and efficiency. In this review, we discuss wider applications of numerous modified chitosan nanoparticles against different tumors and also focusing on the administration of anticancer drugs through various routes. We propose the interaction between nanosized drug carrier and tumor tissue to understand the synergistic interplay. Finally, we elaborate merits of drug delivery system at the tumor site, with emphasizing future challenges in cancer chemotherapy. 相似文献