http://nopr.niscair.res.in/handle/123456789/73 Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/236 Title: Effect of UV-B and high visual radiation on photosynthesis in freshwater (Nostoc spongiaeforme) and marine (Phormidium corium) cyanobacteria <br/> <br/>Authors: Bhandari, Rupali; Sharma, Prabhat Kumar <br/> <br/>Abstract: Human activity is causing depletion of ozone in stratosphere, resulting in increased UV-B radiation and global warming. However, impact of these climatic changes on the aquatic organism (especially marine) is not fully understood. Here, we have studied the effect of excess UV-B and visible radiation on photosynthetic pigments, fatty acids content, lipid peroxidation, nitrogen content, nitrogen reductase activity and membrane proteins, induction of mycosporine-like amino acids (MAAs) and antioxidant enzymes superoxide dismutase (SOD) and ascorbate peroxidase (APX) in freshwater (Nostoc spongiaeform) and marine (Phormidium corium) cyanobacteria. UV-B treatment resulted in an increase in photosynthetic pigments in Nostoc and decrease in Phormidium, but high light treatment caused photobleaching of most of the pigments in both the species. Unsaturation level of fatty acids of both total and glycolipids remained unchanged in both the cyanobacteria, as a result of UV-B and high light treatments. Saturated fatty acids of total and glycolipids declined slightly in Nostoc by both the treatments, but remained unchanged in Phormidium. No changes in the unsaturated lipid content in our study probably suggested adaptation of the organism to the treatments. However, both treatments resulted in peroxidation of membrane lipids, indicating oxidative damage to lipids without any change in the level of unsaturation of fatty acid in the cell membrane. Qualitative and quantitative changes were observed in membrane protein profile due to the treatments. Cyanobacteria were able to synthesize MAAs in response to the UV-B treatment. Both treatments also increased the activities of SOD and APX. In conclusion, the study demonstrated induction of antioxidants such as SOD and APX under visible light treatment and screening pigment (MAAs) under UV-B treatment, which might protect the cyanobacteria from oxidative damage caused by high light and UV-B radiation <br/> <br/>Page(s): 231-239 Sun, 29 Jul 2007 22:58:59 GMT http://nopr.niscair.res.in/handle/123456789/124 Title: Modulation of DMBA-induced biochemical changes by organoselenium compounds in blood of rats <br/> <br/>Authors: Ozdemir, I; Selamoglu, Z; Ates, B; Gok, Y; Yilmaz, I <br/> <br/>Abstract: The protective role of two synthetic organoselenium compounds 1-isopropyl-3-methylbenzimidazole-2-selenone (SeI) and 1, 3-di-p-methoxybenzylpyrimidine-2-selenone (SeII) was examined against the 7,12-dimethylbenz[a]anthracene (DMBA)-induced changes in biochemical parameters in blood of rats. Albino Winstar rats (150-200 g body wt) were treated with single dose of DMBA (50 mg/kg body wt) and organoselenium compounds (25 μmol/kg) for 4 weeks at two days internal. Blood was taken from the anaesthetized rats ventricle from their hearts for biochemical analysis. Administration of DMBA resulted in elevation of urea, uric acid and creatinine levels as well as AST, ALT and LDH activities and decrease in levels of total proteins, albumin and globulin. SeI and SeII caused a significant (p<0.05) decrease in urea, uric acid and creatinine levels and alanine aminotransferase (ALT); aspartate aminotransferase; (AST) and lactate dehydrogenase (LDH) activities and significantly increased the levels of total protein and albumin (p<0.05). These organoselenium compounds are likely to be beneficial in human health. <br/> <br/>Page(s): 257-259 Sun, 29 Jul 2007 22:58:59 GMT http://nopr.niscair.res.in/handle/123456789/123 Title: Purification and some properties of carbonic anhydrase from Elephas trogontherii (Steppe elephant) bone <br/> <br/>Authors: Demir, Yaşar; Nadaroğlu, Hayrunnisa; Demir, Nazan <br/> <br/>Abstract: Four isoenzymes of carbonic anhydrase (CA) were purified from Elephas trogontherii (steppe elephant) bone (approx 0.3-0.5 million years old) from different locations (outer peripheral, cytosolic, inner peripheral and integral) using Sepharose 4B-L-tyrosine sulphanilamide affinity chromatography and their kinetics properties were investigated and compared with known CA isoenzymes. The purification degree of CAs was monitored by SDS-PAGE. Purification fold for outer peripheral, inner peripheral, cytosolic and integral CA was 395.6, 652.8, 1091 and 429.3 and the molecular mass (as determined by gel filtration chromatography) was 37, 36, 35, and 39 kDa, respectively. The optimal temperature for isozymes was 10-20, 30, 30 and 60ºC and optimal pH was between 7.5-11, 7.5-10, 7.5-10 and 7.5 respec-tively. Km values (at optimum pH and 20ºC) for p-nitrophenyl acetate as substrate were 4.83, 6.80, 4.525 and 3.86 mM and the Vmax values for the same substrate were 0.00097, 0.0149, 0.00249 and 0.00072 μmol/L*min, respectively. I₅₀ values of isoenzymes for the inhibitors of CA ̶ sulphanilamide, KSCN, acetazolamide and NaN₃ were also determined. <br/> <br/>Page(s): 252-256 Sun, 29 Jul 2007 22:58:59 GMT http://nopr.niscair.res.in/handle/123456789/122 Title: Purification and properties of an extracellular pectin lyase produced by the strain of Penicillium oxalicum in solid-state fermentation <br/> <br/>Authors: Yadav, Sangeeta; Shastri, N V <br/> <br/>Abstract: A pectin lyase (PNL, EC 4.2.2.10) produced extracellularly by the strain of Penicillium oxalicum in solid-state fermentation medium containing deoiled mandarin orange peel meal was purified to apparent homogeneity by a protocol that included ammonium sulfate precipitation, DEAE-Sephadex A-50 and Sephadex G-100 chromatography. The enzyme had molecular mass of 50 kD, as determined by SDS- PAGE and showed optimum pH and temperature at 8.0 and 50ºC respectively. It had an isoelectric point (pI) of 5.0 and showed a Km of 1.1 mg/ml of citrus pectin. The enzyme was strongly inhibited by Mo⁴⁺, Ag⁺ and Pb²⁺ and also by polyphenolic compounds, in particular tannic acid. <br/> <br/>Page(s): 247-251 Sun, 29 Jul 2007 22:58:59 GMT