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Biomedical subjects

T Chakrabarti

Publications and source records attributed to T Chakrabarti.

40 records · Page 3Linked to original sources
PubMedDate not supplied

Kinetics of biotransformation of 2,4-dichlorophenol using UASB-reactor.

Chlorophenol compounds are environmental pollutants that are both anthropogenic and xenobiotics. Some of these chemicals are carcinogens and are both toxic to a number biochemical processes. Biotransformation of 2,4-dichlorophenol (2,4-DCP) was studied in the presence of glucose on an upflow anaerobic sludge blanket reactor (UASB) using mixed culture. A continuously operated UASB reactor was employed using mixed synthetic wastewater. Results obtained from the 1.8 L volume capacity UASB reactor were subjected to kinetic evaluation constants. Results indicate that the degradation of 2,4-DCP in the presence of glucose was strongly influenced by the concentration of the compound. High degradation levels were observed when the concentration of 2,4-DCP was in the range of 50-150 mg L(-1). Concentrations of 2,4-DCP above 160 mg L(-1) were toxic to microbes even in the presence of glucose. The maximum degradation of 2,4-DCP was found to be 70.4% when initial concentration of 2,4-DCP was 124 mg L(-1) and glucose concentration of 500 mg L(-1) at hydraulic retention time of 13.2 hr. The biodegradation followed first order reaction kinetics with a rate constant (K) of 0.67, Vmax of 0.244 kg m(-3) day(-1), Ks of 0.117 kg m(-3) day(-1) and correlation coefficient of 0.766.

Anaerobiosis↗
PubMedDate not supplied

Effect of exposure to domestic cooking fuels on bronchial asthma.

The effect of indoor air pollution due to domestic cooking with biomass fuel and liquefied petroleum gas (LPG) on the course of bronchial asthma was examined in one hundred non-smoking female asthmatics. The parameters for evaluation were symptoms, emergency visits, and drug requirements. The patients also measured peak expiratory flow rate (PEFR) at home five times daily over a period of one week and the levels of carboxyhaemoglobin (COHb) were estimated randomly during clinic visits. The COHb levels (%) were 4.1 +/- 0.9 and 3.5 +/- 0.6 in the two groups with 22-30% of the subjects reporting increased symptoms during cooking. The number of emergency admissions and the daily requirement of steroids were comparable in both the groups. The PEFR values were lower than the predicted values in both the groups at all times. Further, the readings after exposure to cooking fuels were lower than those before cooking in both the groups (p < 0.01) and these values were similar to those observed during early morning records at 6 AM, which were the lowest. It was concluded that exposure to biomass fuel and LPG affect pulmonary function (PEFR) in asthmatics and both types of fuels affect the airway function and symptoms of bronchial asthma in a similar manner.

Adult↗