Microbial enzymatic reduction of a toxic form of chromium [Cr(VI)] has been considered as an effective method for bioremediation of this metal. This study reports on the in vitro reduction of Cr(VI) using cell-free extracts from a Cr(VI) reducing Bacillusfirmus KUCr1 strain. Chromium reductase was found to be constitutive and its activity was observed both in soluble cell fractions (S₁₂and S₁₅₀) and membrane cell fraction (P₁₅₀). The reductase activity of S₁₂ fraction was found to be optimal at 40 μM Cr(VI) with enzyme concentration equivalent to 0.493 mg protein/ml. Enzyme activity was dependent on NADH or NADPH as electron donor; optimal temperature and pH for better enzyme activity were 70°C and 5.6, respectively. The Km value of the reductase was 58.33 μM chromate having a Vmax of 11.42 μM/min/mg protein. The metabolic inhibitor like sodium azide inhibited reductase activity of membrane fraction of the cell-free extract. Metal ions like Cu²⁺, Co²⁺, Ni²⁺ and As³⁺ stimulated the enzyme but others, such as Ag⁺, Hg²⁺, Zn²⁺, Mn²⁺, Cd²⁺ and Pb²⁺, inhibited Cr(VI) reductase activity.
Background: The aim of the present study was to evaluate & compare the body fluid level and the total mineral content in trained male and female players of four different sport disciplines. Materials and Methods: 46 archers (M=18 & F=28), 57 track & field athletes (M=26 & F=31), 81 footballers (M=24 & F=57) and 43 gymnasts (M=21 & F=22) were evaluated using a multi-frequency bioelectrical impedance analyser. Results: Track & field athletes were found to be bigger in size while gymnasts were smaller. Total body water (%) was found to be higher in all the male players than in their female counterparts. Total mineral mass, total body Ca2+ and K+ were also found to differed significantly (p<0.05 & p<0.01) between male & female players of different sports disciplines, except for gymnastics. However, overall significant difference (p<0.05 & p<0.01) was observed only in archers vs gymnasts, archers vs footballers in both male & female players when Scheffe’s post hoc test was applied. Conclusions: The present study revealed the influence of specific training load and gender on total body water and mineral content in athletes playing different sports. These findings could be implemented in sports to formulate a systematic training program and also for future comparisons.
The impact of climate change on annual air temperature has received a great deal of attention from climatologists worldwide. Many studies have been conducted to illustrate that changes in temperature are becoming evident on a global scale. Air temperature, one of the most important components of climate parameters, has been widely measured as a starting point towards the apprehension of climate change and variability. The main objective of this study is to analyse the temporal variability of mean monthly temperature for the period of 1941 to 2010 (70 years). To detect the magnitude of trend in mean monthly temperature time series, we have used non-parametric test methods such as The Mann-Kendall test, often combined with the Theil-Sen’s robust estimate of linear trend. Whatever test is used, the user should understand the underlying assumptions of both the technique used to generate the estimates of a trend and the statistical methods used for testing. The results of this analysis reveal that four months – January, February, March and December – indicate a decreasing trend in average temperature, while the remaining eight months have an increasing trend. The magnitude of Mann-Kendall trend statistic Zc for this declining temperature and the magnitude of slope for the months of January, February and December are confirmed at the high significance levels of α = 0.001, 0.01 and 0.1 respectively. Though, the overall trend is positive for monthly as well as seasonally efficient time series.
Background. Metals discharged in wastes from different industries into wetland ecosystems pose a serious threat to the receiving environment. Biotic components grown in the area amass such metals within their body through nutritional uptake and accumulation. The present investigation was carried out to study the extent of accumulation of different waste metals in tissues of cichlids commonly cultured in composite industrial wastewater-fed fishponds (Bheris) in East Calcutta Wetlands (ECW), a Ramsar site in India. Materials and Methods. AAS studies were employed to estimate metal (Cr, Mn, Fe, Cu, Zn, and Pb) concentrations in water, and bottom sediment of fishponds and fish tissues (gill, liver, muscle, and bones) of cichlids: Nile tilapia, Oreochromis niloticus L. and Mozambique tilapia, O. mossambicus (Peters, 1852), collected from contaminated and control sites. Results. The concentrations of metals in bottom sediment were found higher than those of the overlying water. It was evident from the experiment that, either bone or liver was the site of maximum accumulation for the elements while muscles were the site of least metal accumulation in both fish species. Chromium, which was a highly publicised contaminant of tannery effluents, showed a similar distribution pattern (muscle < gill < liver < bone) in these fishes. Concentrations of non-essential metals like Pb were highest in Nile tilapia liver (17.9 mg • kg-1) followed by Mozambique tilapia liver (14.7 mg • kg-1). Principal component analysis with Varimax rotation revealed that Fe and Mn were in the first and second component, respectively, to influence metal uptake and bioaccumulation. Conclusion. Tissue-specific and species-specific patterns of metal concentration and partitioning were apparent from our experimentation. Dendrograms showed two definite clustering pattern, gill and muscle in one cluster with bone and liver in the other, two important organs so far as partitioning (in bone) and detoxification (in liver) were concerned.
A chromium resistant bacterial strain KUCr1 exhibiting potential Cr(VI) reducing ability under in vitro aerobic condition is reported. The bacterial strain showed varied degree of resistance to different heavy metals. The MIC of chromium to this strain was found to be 950 mM under aerobic culture condition in complex medium. The factors affecting Cr(VI) reduction by this strain under culture condition were evaluated. Maximal Cr(VI) reduction was observed at the pH 8 to 10 and at a temperature of 35°C. Higher concentration of Cr(VI) slowed down the reduction, eventually all the metal could be reduced with longer incubation time. Different toxic metals showed differential effect on reduction. Cadmium and zinc were found to inhibit reduction. Cr(VI) reduction and bioremediation were found to be related to the growth supportive condition in terms of carbon, phosphorous and nitrogen supply in wastewater fed with tannery effluent indicating cell mass dependency of Cr(VI) reduction. Through biochemical characterization and 16S rDNA sequence analysis, the strain KUCr1, as the name given to it, was identified as a strain of Bacillus firmus.
A continuous 2-year volumetric aerobiological survey was conducted in Berhampore town, a centrally located and representative part of West Bengal, India. The aim of the study was to assess the allergising potential of airborne pollen grains of West Bengal. A total of 31 pollen types were identified of which Poaceae (grasses) pollen showed maximum frequency, followed by Cyperaceae, Cassia sp., Acacia auriculiformis, etc. The seasonal periodicities of the pollen types and their relationship to meteorological conditions were investigated. It was found that the pollen concentration is positively correlated with temperature and negatively correlated with rainfall and relative humidity. Clinical investigations by skin prick test were carried out to detect allergenicity of pollen types. Eighteen common airborne pollen types induced positive responses of which pollen extracts of Saccharum officinarum (grass), Azadirachta indica, Cocos nucifera, Phoenix sylvestris, Cyperus rotundus and Eucalyptus citriodora showed strongest sensitising potential. This result is consistent with previous investigations in different parts of West Bengal.
The present study aimed to compare various physical and body composition profiles of Indian male and female gymnasts and also to compare the above parameters with their international/national peers. The study was conducted on15 male (age = 19.2 ±3.75 years) and 16 female Indian gymnasts (age = 16.4 ±2.99 years). Various physical and body composition parameters were measured using standard methods. The female gymnasts were found to have a higher amount of fat mass and volumes of extracellular water than their male and international peers while the males had a higher amount of fat free mass than females but less than their international peers. Also male gymnasts had a higher amount of body cell mass (BCM) and muscle mass (MM) than females and their international peers. The hand grip strengths, trunk flexibility, relative back strength and electrolytes were also found to be greater in male gymnasts. Significant positive correlations were observed in BCM and MM with calcium, potassium, glycogen and mineral content in both male and female gymnasts. These profiles of gymnasts may be used as a tool for evaluation & assessment and a future comparison for the improvement in performance.
Constitutive (COX-1) and inducible (COX-2) cyclooxygenase isoforms have been detected in various mammalian tissues. Their activity is blocked by non-steroidal anti-inflammatory drugs that may induce various side reactions. The aim of the study was to evaluate the effects of DFU, a selective COX-2 inhibitor, on exocrine and endocrine pancreatic function and the immunoexpression of both COX isoforms in maternal and foetal rat pancreases. The compound was administered to pregnant Wistar rats once daily from the 8th to the 21st day of gestation. Glucose level and amylase activity were determined in the maternal sera. Maternal and foetal pancreases were examined histologically. Immunoexpression of COX-1 and COX-2 was also evaluated. Both biochemical parameters, as well as the histological structure of the pancreas were undisturbed in the dams and their foetuses. The maternal glucose level was found to be an important factor for foetal growth. Strong cytoplasmic COX-1 immunostaining was observed in acinar secretory cells, whereas in islets the immune reaction was weak. Endocrine cells also revealed strong cytoplasmic COX-2 staining in the maternal and foetal pancreases. Acinar cells exhibited nuclear reaction, which was strong in the foetal but weak in the maternal pancreases. No differences in COX immunoexpression were found between the DFU-exposed and the control groups in either mothers or foetuses. It should be stressed that DFU administered throughout mid and late pregnancy in rats did not change maternal or foetal pancreatic morphology or immunoexpression of either of the main COX isoforms in the organ.
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