http://nopr.niscair.res.in/handle/123456789/3692 Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/3814 Title: An assessment of biopotential of three cyanobacterial isolates from Antarctic for carotenoid production <br/> <br/>Authors: Shukla, S P; Kashyap, A K <br/> <br/>Abstract: Specific growth rates and carotenoid contents of three Antarc-tic and tropical strains of cyanobacteria viz. Anabaena sp., Phor-midium sp. and Nostoc sp. were compared in batch and mass cul-tures to assess bio-potential of Antarctic strains for cost-effective carotenoid production. Antarctic strains though exhibited slightly lower specific growth rates, but contained higher carotenoid con-tents (per unit dry wt.), than tropical strains. Modification of nor-mal composition of BG-11 culture medium, by altering nitrogen and carbon sources resulted in 25-38% increase in carotenoid content in both types of strains. Mass-culture in indoor and semi-outdoor bio-reactors resulted in 39-113% higher carotenoid con-tent in Antarctic strains, compared to their respective tropical strains. The observations suggest that Antarctic cyanobacteria may have potential as superior strains for maximizing the yield of carotenoids. <br/> <br/>Page(s): 362-366 Sun, 28 Sep 2003 22:58:59 GMT http://nopr.niscair.res.in/handle/123456789/3813 Title: Effects of some flavonoids on the susceptibility of low-density lipoprotein to oxidative modification <br/> <br/>Authors: Safari, Mohammad-Reza; Rezaie, Mohsen; Sheikh, Nasrin <br/> <br/>Abstract: The effects of six flavonoids viz., apigenin, genistein, morin, naringin, pelargonidin and quercetin on the susceptibility of low-density lipoprotein (LDL) to oxidative modification were investigated. Flavonoids were added to plasma and incubated for 3 hr at 37°C, and the LDL fraction was separated by ultracentrifugation. Oxidizability of LDL was estimated by measuring conjugated diene (CD), lipid peroxides and thiobarbituric acid-reactive substances (TBARS), after cupric sulfate solution was added. Quercetin and morin significantly (P<0.01 by ANOVA) prolonged the lag time before initiation of oxidation reaction in dose-dependent manner. They also suppressed the formation of lipid peroxides and TBARS more markedly than other flavonoids. The ability to prolong lag time and suppression of lipid peroxides and TBARS formation was in the following order: quercetin >morin >pelargonidin >genistein >naringin >apigenin. LDL exposed to flavonoids reduced oxidizability. These findings suggest that flavonoids may have a role in ameliorating atherosclerosis. <br/> <br/>Page(s): 358-361 Sun, 28 Sep 2003 22:58:59 GMT http://nopr.niscair.res.in/handle/123456789/3812 Title: Hepatoprotective and antioxidant effect of tender coconut water on carbon tetrachloride induced liver injury in rats <br/> <br/>Authors: Loki, Anthony Loperito; Rajamohan, T <br/> <br/>Abstract: Hepatoprotective and antioxidant effects of tender coconut water (TCW) were investigated in carbon tetrachloride (CCl₄)-intoxicated female rats. Liver damage was evidenced by the increased levels of serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT) and decreased levels of serum proteins and by histopathological studies in CCl₄-intoxicated rats. Increased lipid peroxidation was evidenced by elevated levels of thiobarbituric acid reactive substance (TBARS) viz, malondialdehyde (MDA), hydroperoxides (HP) and conjugated dienes (CD), and also by significant decrease in antioxidant enzymes activities, such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (Gpx) and glutathione reductase (GR) and also reduced glutathione (GSH) content in liver. On the other hand, CCl₄-intoxicated rats treated with TCW retained almost normal levels of these constituents. Decreased activities of antioxidant enzymes in CCl₄-intoxicated rats and their reversal of antioxidant enzyme activities in TCW treated rats, shows the effectiveness of TCW in combating CCl₄-induced oxidative stress. Hepatoprotective effect of TCW is also evidenced from the histopathological studies of liver, which did not show any fatty infiltration or necrosis, as observed in CCl₄-intoxicated rats. <br/> <br/>Page(s): 354-357 Sun, 28 Sep 2003 22:58:59 GMT http://nopr.niscair.res.in/handle/123456789/3811 Title: Activation of tobacco leaf polyphenol oxidase by sodium dodecyl sulfate <br/> <br/>Authors: Jiang, Hui; Shi, Chunhua; Xie, Yongshu; Xu, Xiaolong; Liu, Qingliang <br/> <br/>Abstract: The effect of sodium dodecyl sulfate (SDS) on purified tobacco leaf PPO (PPO II) was investigated at various pHs and temperatures. SDS increased the activity of PPO II due to the formation of SDS-PPO II complex, leading to conformational changes, thus making access to active center easier. The relationship between the activity and the molar ratio of SDS-PPO II to PPO II showed that the critical point reached a plateau of activity at the molar ratio of about 1.2. The pH had a significant effect on interaction between SDS and PPO II, as compared to PPO II. The optimum catalytic temperature of the complex rose by 10°C, suggesting that stabilization of the structure had been improved by the formation of complex. <br/> <br/>Page(s): 350-353 Sun, 28 Sep 2003 22:58:59 GMT