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The present study was aimed towards the effective bio-treatment of actual industrial effluent containing as high as 42,000 mg/L COD (chemical oxygen demand), >28,000 ADMI (American Dye Manufacturers Institute) color value and four heavy metals using indigenous developed bacterial consortium TSR. Mineral salt medium supplemented with as low as 0.02% (w/v) yeast extract and glucose was found to remove 70% ADMI, 69% COD and >99% sorption of heavy metals in 24 h from the effluent by consortium TSR. The biodegradation of effluent was monitored by UV-vis light, HPLC (high performance liquid chromatography), HPTLC (high performance thin layer chromotography) and FTIR (Fourier transform infrared spectroscopy) and showed significant differences in spectra of untreated and treated effluent, confirming degradation of the effluent. Induction of intracellular azoreductase (107%) and NADH-DCIP reductase (128%) in addition to extracellular laccase (489%) indicates the vital role of the consortium TSR in the degradation process. Toxicity study of the effluent using Allium cepa by single cell gel electrophoresis showed detoxification of the effluent. Ninety per cent germination of plant seeds, Triticum aestivum and Phaseolus mungo, was achieved after treatment by consortium TSR in contrast to only 20% and 30% germination of the respective plants in case of untreated effluent.

A bacterial strain, B12, proficient in decolourizing commercial dye -Reactive Blue 160 (RB160) was isolated from the soil sample collected from a textile industry. Phenotypic characterization and phylogenetic analysis of the 16S rDNA sequence indicated that the bacterial strain belonged to the genus Microbacterium. Bacterial isolate B12 showed 96% decolourization of RB160 at the concentration of 250 mg/l under microaerobic conditions with temperature 35 ± 2°C and pH 5.0 in 24 h. The decolourization efficiency of isolate B12 was improved by using physical and chemical mutagens, the mutant strain offered 12 h reduction in time required for the complete decolourization by wild strain when exposed to 30 sec of UV radiation and 0.5µg/ml of acridine orange. The laccase and reductase enzymes cleaved RB160 and metabolised the degraded product, the different intermediates were identified using HPLC and LC-MS. The phytotoxicity studies confirmed that intact RB160 was more toxic than dye degraded intermediates. Microbacterium sp. B12 was found competent to degrade RB160 containing textile industry effluents showing the usefulness of the organism for possible commercial application. K e y w o r d s Microbacterium sp., Azo dye, Reactive Blue 160, LC-MS, Random mutagenesis.

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Synthesis of metal nanoparticles using efficient, eco-friendly green chemistry methods is widely applied nowadays. Use of plant extract is one of the most considered methods as it is more stable and the rate of synthesis is faster. In this study, for the first time, we synthesized biocompatible, eco-friendly and cost-effective copper nanoparticles (CuNPs) using a well-characterized plant Citrus limon, a natural product, which acts as a reducing agent. The synthesized CuNPs were characterized by UV–Vis spectroscopy and dynamic light scattering and were applied to investigate the antibacterial and antifungal activities along with their fluorescent properties. The microwave-assisted green CuNPs-treated cotton fabric exhibited high efficiency against both Gram-positive and Gram-negative bacteria and fungi. The particles showed highest activity against Gram-negative bacteria Escherichia coli. In future, the in vivo toxicity studies of these nanomaterials will allow the formulation of new types of antimicrobial materials for pharmaceutical and biomedical applications, such as antimicrobial next-to-skin fabrics.