Degradation of atrazine in mineral salts medium and soil using enrichment culture

Atrazine degrading enrichment culture was prepared by its repeated addition to an alluvial soil and its ability to degrade atrazine in mineral salts medium and soil was studied. Enrichment culture utilized atrazine as a sole source of carbon and nitrogen in mineral salts medium and degradation slowed down when sucrose and/or ammonium hydrogen phosphate were supplemented as additional source of carbon and nitrogen, respectively. Biuret was detected as the only metabolite of atrazine while deethylatrazine, deisopropyatrazine, hydroxyatrazine and cyanuric acid were never detected at any stage of degradation. Enrichment culture degraded atrazine in an alkaline alluvial soil while no degradation was observed in the acidic laterite soil. Enrichment culture was able to withstand high concentrations of atrazine (110 μg/g) in the alluvial soil as atrazine was completely degraded. Developed mixed culture has the ability to degrade atrazine and has potential application in decontamination of contaminated water and soil.     

In Vitro Cytotoxicity of Amylose-Based Bioplastic for Packaging Applications

Amylose containing polysaccharides are one of the most abundant and inexpensive naturally occurring biopolymers. Therefore, they are one of the most promising candidates to produce substitute plastics, especially in packaging applications. To determine the suitability for packaging applications, cytotoxicity of a modified amylose based bioplastic was investigated using NIH 3T3 Fibroblast cells from observation of cell morphology and MTS assay. Chemical durability of the amylose based bioplastic film was also studied by ion release and pH measurement after immersing the film into water. In vitro cytotoxicity (Cell morphology study and MTS assay) showed that the amylose based bioplastic film has in vitro biocompatibility and can be used for packaging applications. The ion release and pH measurement also supported the results.     

Overview on recent advances of magnetic metal–organic framework (MMOF) composites in removal of heavy metals from aqueous system

Environmental Science and Pollution Research - Developing a novel, simple, and cost-effective analytical technique with high enrichment capacity and selectivity is crucial for environmental...     

A grave danger for the Ganges dolphin (Platanista gangetica Roxburgh) in the Subansiri River due to a large hydroelectric project

The Ganges River dolphin (Platanista gangetica Roxburgh) of Subansiri River may be in great danger of extinction due to the construction of the 2,000-MW Lower Subansiri Hydroelectric Project, which started in 2006. A recent survey indicates that there are now 29 Ganges dolphins, up from 21 in 2006. It is feared that drastic changes would occur in the downstream hydrology and ecology of the Subansiri River after the installation of the project, scheduled for 2012. The water discharge during a major part of the day in dry months would come down to a meager 6 cumecs from the present average of 450 cumecs (1 cumec is shorthand for cubic meter per second; also cms, or m³/s (m³s^–1). Riverine mega fauna like the dolphin would be worst hit by this extremely low discharge. Dumping of an extra amount of sediment from different construction phases has already increased sediment load in the Subansiri downstream and degraded some earlier pockets of dolphin up to 20 km below the dam site. There is reason to believe that high sediment influx might have silted up some of the deeper pools downstream, a preferred habitat of dolphins, forcing them to congregate close to the confluence of the Subansiri.     

Epigenetics: a new warrior against cardiovascular calcification,a forerunner in modern lifestyle diseases

Arterial and aortic valve calcifications are the most prevalent pathophysiological conditions among all the reported cases of cardiovascular calcifications. It increases with several risk factors like age, hypertension, external stimuli, mechanical forces, lipid deposition, malfunction of genes and signaling pathways, enhancement of naturally occurring calcium inhibitors, and many others. Modern-day lifestyle is affected by numerous environmental factors and harmful toxins that impair our health rather than providing benefits. Applying the combinatorial approach or targeting the exact mechanism could be a new strategy for drug designing or attenuating the severity of calcification. Most of the non-communicable diseases are life-threatening; thus, altering the phenotype and not the genotype may reveal the gateway for fighting with upcoming hurdles. Overall, this review summarizes the reason behind the generation of arterial and aortic valve calcification and its related signaling pathways and also the detrimental effects of calcification. In addition, the individual process of epigenetics and how the implementation of this process becomes a novel approach for diminishing the harmful effect of calcification are discussed. Noteworthy, as epigenetics is linked with genetics and environmental factors necessitates further clinical trials for complete and in-depth understanding and application of this strategy in a more specific and prudent manner.

     

Effect of chlorpyrifos on microbial biomass and activities in tropical clay loam soil

Clay loam soil from agricultural field of Gangetic alluvial zone of West Bengal was investigated to evaluate the effect of chlorpyrifos application at field rate (0.5 mg kg^???1 soil) and 100 times of the field rate (50 mg kg^???1 soil) on soil microbial variables under laboratory conditions. Acetone-induced stress on soil microorganisms was evident in the initial stages in terms of microbial biomass carbon (MBC) content in soil and basal soil respiration (BSR) in control soil samples which received acetone only as compared to control soil without acetone. The soil MBC content increased significantly by application of chlorpyrifos. The BSR and the fluorescein diacetate hydrolysing activity (FDHA) were not adversely affected by chlorpyrifos at field rate, whilst the chemical at higher dosage significantly decreased the metabolic activities of soil microbes in terms of BSR and FDHA.     

Statewide Survey of Hormones and Antibiotics in Surface Waters of Delaware

Water‐quality surveys have confirmed the presence of hormones and antibiotics in surface waters of the United States, which may be of concern to aquatic life. We investigated the concentrations of hormones and antibiotics in surface waters of the state of Delaware to determine – how they compared against environmental thresholds, how they varied across the state, and if they were correlated with land use type. Fifty surface water locations were sampled during early spring and late summer. Water samples were initially screened with ELISA followed by analysis with LC/MS/MS. The measured ranges of hormone concentrations were: 0‐3.71 ng/l for estrone, 0‐4.65 ng/l for estrone‐3‐sulfate, and 0‐6.27 ng/l for 17β‐estradiol. The measured ranges of antibiotics were: 0‐3.30 ng/l for sulfamerazine, 0‐10.74 ng/l for sulfamethoxazole, and 0‐2.29 ng/l for tetracycline. The predicted no‐effect concentration (PNEC) for estrone was exceeded for three samples and the PNEC for 17β‐estradiol was exceeded for 11 samples. In general, concentrations and detection frequencies were lower in the summer than the spring. The highest concentrations of hormones and antibiotics were spatially distributed in agricultural and urban areas; however, the correlations between land use type and the concentrations were weak. This study was the first statewide survey of hormones and antibiotics for Delaware and provided important baseline data on these emerging contaminants.     

Acid-enhanced limestone defluoridation in column reactor using oxalic acid

Acid enhanced limestone defluoridation of water has been studied in a crushed limestone column reactor using oxalic acid (OA). The defluoridation has been studied with varying initial fluoride concentrations of 5, 10, 15 and 20 mg/L and acid concentrations of 0.01, 0.05 and 0.1 M. The fluoride removal was found to increase with increase in the concentration of the acid, removing fluoride up to 95% with 0.1 M OA. The observed good fluoride removal has been attributed to a combination of two mechanisms of fluoride removal, viz., precipitation of calcium fluoride and adsorption of fluoride ions on limestone surfaces. While the removal by precipitation remains same on repeated use of the same limestone column, the adsorption is more with the fresh limestone and decreases gradually on repeated use of the same limestone column. The precipitate has been characterized using various analytical tools, viz., X-ray diffraction, IR spectroscopy, thermogravimetric analysis, scanning electron microscopy combined with energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. The Ca²⁺ ions, formed due to dissolution of limestone by the acid, precipitate calcium fluoride along with precipitation of calcium oxalate. A good fluoride removal ability, low residual oxalate, acceptable final pH, low-cost and simplicity of the process make the present acid-enhanced limestone defluoridation process with OA a potential method for defluoridation of groundwater.