NISCAIR Online Periodicals Repository Collection: IJEB Vol.50(09) [September 2012]

Eclosion behaviour of three species of Drosophila under different light regimes

Wed, 29 Aug 2012 22:58:59 GMT

Title: Eclosion behaviour of three species of Drosophila under different light regimes

Authors: Kouser, Shereen; Shakunthala, V

Abstract: The daily patterning of animal behaviour is presumed to be due to changes in responsiveness to external stimuli, as a function of varying internal states which may be oscillating with a 24 h period. The endogenous circadian system functions to organize behaviour and physiology to adapt to and anticipate environmental changes in light, temperature, food and mate availability. Light is most important zeitgeber that influence circadian physiology of several insects. The present study is an attempt to understand the eclosion behaviour of Drosophila melanogaster (Oregon-K strain), Drosophila gangotrii and Drosophila jambulina under light/dark (LD), continuous light (LL), continuous dark (DD) conditions for 30 generations. The stocks were maintained at 20±1 °C with 75% RH. Eclosion behaviour was analyzed at 4 h intervals until complete emergence of flies. Result reveals that in all the species peak of eclosion was found at dawn and on subjective day. Intraspecies comparison shows that there was no significant difference in eclosion at different time point and generations under different light regimes. However, interspecies comparison shows significant difference for hours. The data from experiments showed altered rhythm in the form of phase advance and phase delay in eclosion at different light regimes suggesting the role of photoperiod in the physiology of organisms.

Page(s): 660-664

Functional ureogenesis and changes of amino acid metabolism in amphihaline shad hilsa (Tenualosa ilisha, Hamilton-Buchanan) while inhabiting in estuary and freshwater habitats

Wed, 29 Aug 2012 22:58:59 GMT

Title: Functional ureogenesis and changes of amino acid metabolism in amphihaline shad hilsa (Tenualosa ilisha, Hamilton-Buchanan) while inhabiting in estuary and freshwater habitats

Authors: Goswami, Umesh C; Rahman, Makibur; Saha, Nirmalendu

Abstract: The possible occurrence of a functional ornithine-urea cycle (OUC) and changes of activity of key amino acid metabolism-related enzymes were studied in the amphihaline shad hilsa (Tenualosa ilisha) that were collected from estuarine water of Kakdwip and from freshwater river basin of Bhrahmaputra during the breeding season. Very high concentration of urea was detected in different tissues and plasma of shad hilsa collected from estuarine water compared to the one collected from freshwater river basin. This observation clearly suggests that the shad hilsa has the potential of synthesizing and retaining urea inside the body for the purpose of osmoregulation while living in hypertonic saline environment of estuary. This was accompanied by the presence of high activity of all the five OUC enzymes in hepatic and in certain non-hepatic tissues such as the kidney and muscle of shad hilsa in support of its potential ureogenic capacity while inhabiting in estuarine water. The activities of different key amino acid metabolism-related enzymes such as glutamine synthetase, glutamate dehydrogenase, alanine aminotransaminase and aspartate aminotransaminase were also found to be significantly higher in shad hilsa of estuarine water compared to the one collected from freshwater habitat. Thus the adjustment to amino acid metabolism in shad hilsa in different environmental salinities appears to play significant roles for osmotic balance and also for proper energy supply in addition to the presence of a functional OUC while migrating between marine and freshwater habitats throughout their life cycle.

Page(s): 652-659

Thirteen-week oral toxicity study of carotenoid pigment from Rhodotorula glutinis DFR-PDY in rats

Wed, 29 Aug 2012 22:58:59 GMT

Title: Thirteen-week oral toxicity study of carotenoid pigment from Rhodotorula glutinis DFR-PDY in rats

Authors: Latha, B V; Jeevaratanm, K

Abstract: Carotenoids from some of the coloured yeasts like Rhodotorula, Phaffia rhodozyma have attracted commercial interest as a natural pigment for foods. Red yeast isolated from contaminated Potato dextrose agar plate (PDA), designated as Rhodotorula glutinis DFR-PDY has been found to produce carotenoids. In the present study toxicological evaluation of carotenoid pigment has been reported. Experiment was conducted on 3 groups of albino rats. One group with vehicle control (palm oil) and 2 groups with two different doses of red yeast pigment (lower and higher dose) were fed to rats (both male and female) by gavages for 13 weeks. Gain in body weight of rats and food consumption were monitored at regular intervals. Hematological studies revealed that there is no much difference in erythrocytes, packed cell volume, Mean corpuscular volume (MCV), Mean corpuscular haemoglobin concentration (MCHC), platelets and differential counts. Total leucocyte count (TLC) is less in case of higher dose group than the lower and control groups. Whereas, hemoglobin is more in case of higher dose than the lower dose group and least in control group. Even clinico-chemical parameters and urine analysis of vehicle control group and pigment fed rats revealed that there were no major differences between them as well as between two different genders of rats and also interaction between different doses and the genders. Histopathology of these experimental animals revealed that there are no major histological changes found between the groups. It may be concluded that the whole pigment extract from R. glutinis DFR-PDY may be used safely in food preparations as food colourant with an added benefit of antioxidant activity .

Page(s): 645-651

Protective effects of subchronic caffeine administration on cisplatin induced urogenital toxicity in male mice

Wed, 29 Aug 2012 22:58:59 GMT

Title: Protective effects of subchronic caffeine administration on cisplatin induced urogenital toxicity in male mice

Authors: Khazaei, M; Bayat, P D; Ghanbari, A; Khazaei, S; Feizian, M; Khodaei, A; Alian, H A S

Abstract: In Cisplatin treated group, the degeneration intensity of the kidneys the diameter of seminiferous tubules as well as the apoptotic index in testes and kidney were increased. In Caffeine+Cisplatin treated groups, the total body weight, the weight of testes and kidneys and also the histopathological data did not show significant differences. The motility of sperm in cisplatin group reduced but in Caffeine+Cisplatin groups this parameter was increased. These data suggest that caffeine recovers toxicity induced by cisplatin in both kidneys and testes of mice.

Page(s): 638-644