NISCAIR Online Periodicals Repository Collection: IJEB Vol.48(05) [May 2010]

Enhancement of magnetotactic bacterial yield in a modified MSGM medium without alteration of magnetosomes properties

Wed, 28 Apr 2010 22:58:59 GMT

Title: Enhancement of magnetotactic bacterial yield in a modified MSGM medium without alteration of magnetosomes properties

Authors: Kundu, Srikanya; Kulkarni, Gauri R

Abstract: Magnetotactic bacteria (MTB), Magnetospirillum magnetotacticum (MS-1) were successfully grown in modified magnetic spirillum growth medium (MSGM) at normal laboratory environment. About five-time increase in the bacterial yield was achieved in the modified MSGM medium without compromising their magnetosomes properties. Transmission electron and scanning electron microscopy (TEM & SEM) were used for morphological study of MTB. Energy dispersive analysis of X-rays (EDAX) and vibrating sample magnetometer (VSM) techniques, respectively, were used to elucidate the phase and magnetization in the bacterially synthesized magnetosomes. These studies were important to cross-check the morphology of magnetosomes, as the formation of magnetosomes was highly sensitive to environmental conditions.

Page(s): 518-523

Effect of carnitine supplementation on mitochondrial enzymes in liver and skeletal muscle of rat after dietary lipid manipulation and physical activity

Wed, 28 Apr 2010 22:58:59 GMT

Title: Effect of carnitine supplementation on mitochondrial enzymes in liver and skeletal muscle of rat after dietary lipid manipulation and physical activity

Authors: Karanth, Jyothsna; Jeevaratnam, K

Abstract: Effect of carnitine supplementation in enhancing fat utilization was investigated by looking into its effects on mitochondrial respiratory enzymes activity in liver and muscle as well as on membrane fatty acid profile in rats fed with hydrogenated fat (HF) and MUFA-rich peanut oil (PO) with or without exercise. Male Wistar rats were fed HF-diet (4 groups, 8 rats in each group) or PO-diet (4 groups, 8 rats in each group), with or without carnitine for 24 weeks. One group for each diet acted as sedentary control while the other groups were allowed swimming for 1 hr a day, 6 days/week, for 24 weeks. The PO diet as well as exercise increased the activities of mitochondrial enzymes, NADH dehydrogenase, NADH oxidase, cytochrome C reductase, cytochrome oxidase, while carnitine supplementation further augmented the oxidative capacity of both liver and muscle significantly by enhancing the activity of carnitine palmitoyl transferase and the respiratory chain enzymes. These effects can be attributed to the enhanced unsaturated fatty acids in phospholipids of mitochondria and may be due to increased fluidity of the membrane in these rats. Results of this study show a significant health promoting effects of carnitine supplementation which could be further augmented by regular exercise.

Page(s): 503-510

Racial divergence of a rare laboratory evolved centromeric fission Cytorace of nasuta-albomicans complex of Drosophila

Wed, 28 Apr 2010 22:58:59 GMT

Title: Racial divergence of a rare laboratory evolved centromeric fission Cytorace of nasuta-albomicans complex of Drosophila

Authors: Bijaya, Thongatabam; Ramachandra, Nallur B

Abstract: Fissioncytorace-1, a member of the nasuta-albomicans complex of Drosophila is an evolutionary product of centric fission, which had occurred in the chromosome X3 of Cytorace 1, a hydridization product of Drosophila nasuta nasuta male (2n=8) and Drosophila nasuta albomicans female (2n=6). Cytorace 1 (males 2n=7; females 2n=6) has inherited this chromosome from its D. n. albomicans parent. The chromosome X3 of D. n. albomicans is a derivative of a centric fusion between the acrocentric chromosome 3 and the chromosome X of D. n. nasuta. The Fissioncytorace-1 has crossed 200 generations from the time of its evolution in the laboratory environment. When this centromeric fission race was subjected to some of the morphophenotypic and fitness assessment to find its overall population fitness showed, increased body size, sternopleural bristle, ovarioles, lifetime fecundity and fertility with reduced interspecific competitive ability and hatching success when compared with its parent (Cytorace 1). These results suggest that the hybrid races must have encountered an early event of recombinational raciation during their evolution in the laboratory environment, which is a unique observation in animal system illustrating the increase in the tempo of evolution after the event of hybridization.

Page(s): 511-517

Effect of Cyclea peltata Lam. roots aqueous extract on glucose levels, lipid profile, insulin, TNF-α and skeletal muscle glycogen in type 2 diabetic rats

Wed, 28 Apr 2010 22:58:59 GMT

Title: Effect of Cyclea peltata Lam. roots aqueous extract on glucose levels, lipid profile, insulin, TNF-α and skeletal muscle glycogen in type 2 diabetic rats

Authors: Kirana, H; Srinivasan, B P

Abstract: In view of multi-dimensional activity of plant drugs beneficial to complex disorders like diabetes, the present study has been undertaken to evaluate the effect of aqueous extract of C. peltata roots on serum glucose, lipid profile, insulin, inflammatory marker namely tumour necrosis factor (TNF)-α and muscle glycogen in type 2 diabetic rats. Aqueous extract of C. peltata at 40 and 60 mg/kg dose significantly decreased both the fasting and postprandial blood glucose of type 2 diabetic rats; 60 mg/kg dose having more pronounced effect on hyperglycemia. An enhanced insulin levels by the aqueous extract is primary for its glucose and lipid lowering activity. The extract significantly decreased the elevated TNF-α in type 2 diabetic rats. The extract at 40 and 60 mg/kg dose increased the glycogen levels in skeletal muscle by 58 and 60% respectively. Improved glycogen in peripheral tissue such as skeletal muscle indicates the ability of plant drug to combat insulin resistance of type 2 diabetes.

Page(s): 499-502