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The efficient cellulolytic microorganism was isolated from soil samples collected from Shivaji University campus. Biochemical test and phylogenetic analysis of isolated culture identified as Klebsiella sp. PRW-1. The isolated culture could utilize pure cellulosic substrates (carboxymethylcellulose (CMC) and avicel) and different agricultural wastes like sugarcane bagasse, sugarcane barbojo, sorghum husks, grass powder, corn straw and paddy straw by producing a large amount of endoglucanase, exoglucanase, β-glucosidase, filter paperase (FPU), xylanase and glucoamylase. The reducing sugar production was found higher in the presence of grass powder and sugarcane barbojo. Effects of different physic-chemical parameters to achieve maximum cellulolytic enzymes production were systematically investigated. The effects of supplementation of different metals additives as well as the stability in the presence of higher temperature, pH and commercial detergents, on cellulolytic enzymes were also studied. The foregoing result increases the applicability of the strain for the utilization and bioconversion of lignocellulosic biomass that could be used for bioenergy production. [ABSTRACT FROM AUTHOR]

The effect of zinc plating industrial effluent on some biochemical parameters and the phytoremedial capacity of floating aquatic macrophyte Azolla caroliniana was assessed. The effects of increasing zinc concentrations on growth characteristics of A. caroliniana namely root length, leaf area and biomass production was studied. The root growth of A. caroliniana was severely affected at higher concentration of zinc effluent (especially at 3 and 4%). Overall slight fluctuations in the moisture content represent the favorable nature of this essential micronutrient especially at 1% and 2% concentration. Maximum chlorophyll contents were observed at 2% concentration of the effluent with an increase by 41.29% over the control. The least amount of carotenoid was observed at 4% concentration. Polyphenol content of the fronds of A. caroliniana was lowest at 4% while higher accumulation was observed at 2% effluent concentration. The level of proline in the leaves of A. caroliniana was considerably increased under the influence of zinc especially at 1, 2 and 3% of the effluent concentration. It was also seen that electrical conductivity (EC) and total dissolved solids (TDS), content of the various dilution were decreased remarkably after 10 days of treatment. pH of the solution tend to become neutral while increase in turbidity might be related with root exudates and dead organics by the plant growing in the tray. The decrease in hardness, acidity, sodium and potassium content of the effluent were observed with increase in concentration of the effluent. Values for biological oxygen demand (BOD) were decreased in the effluent concentration of 2% while the decrease in chemical oxygen demand (COD) was maximum in the same effluent concentration after 10 days treatment period. Zinc was accumulated in increasing order in the plants treated with increasing concentration of zinc. The bio concentration factor (BCF) values were increased serially as per increasing concentration of zinc plating effluent and all the plants growing in these concentrations showed higher accumulation capacities. 4% of the effluent recorded with higher BCF while minimum for control treated biomass was observed. In the present study increasing BCF shows that the A. caroliniana has capacity to accumulate the Zn++ through liquid medium after ten days of exposure period. [ABSTRACT FROM AUTHOR]

Salinity is one of the major abiotic stress that adversely affects on crop productivity and its quality. The present investigation was carried out to study the alterations in the growth characteristics, photosynthetic pigments and polyphenols content of Vetiveria zizanioides (L.) under the influence of sodium chloride salinity. The result shows that the shoot length of Vetiveria zizanioides was increased by 18.6% at 200 mM NaCl concentration whereas, the increase in root length about 24.8% was observed at 50 mM NaCl. Shoot to root ratio in the experimental species was reduced to 10.0% at 50 mM NaCl concentration whereas at 300 mM of salinity it was increased by 39.09%. Moreover, the average leaf area also increases under saline conditions. An increase in the photosynthetic pigments at lower salt levels indicates osmotic adjustment mechanism developed by the grass species to incumbent with salt stress. However, dry weight and fresh weight of the plant biomass was found less effective under the salinity stress. The increased levels of polyphenols at elevated salinity might be due to the accumulation of secondary metabolites. Linear increase in the electrical conductivity and total dissolved solids of the soil was observed at increasing salinity. Increase in growth and photosynthetic parameters observed at especially upto 100 mM of salinity indicate the tolerance shown by experimental species and we conclude that tolerant V. zizanioides can be grown in saline areas with salt concentrations up to 200 mM. [ABSTRACT FROM AUTHOR]

Co-naphthalocyanine (CoNPc) was prepared by heat treatment for cathode catalysts to be used in microbial fuel cells (MFCs). Four different catalysts (Carbon black, NPc/C, CoNPc/C, Pt/C) were compared and characterized using XPS, EDAX and TEM. The electrochemical characteristics of oxygen reduction reaction (ORR) were compared by cyclic voltammetry (CV) and linear sweep voltammetry (LSV). The Co-macrocyclic complex improves the catalyst dispersion and oxygen reduction reaction of CoNPc/C. The maximum power of CoNPc/C was 64.7 mW/m(2) at 0.25 mA as compared with 81.3 mW/m(2) of Pt/C, 29.7 mW/m(2) of NPc/C and 9.3 mW/m(2) of carbon black when the cathodes were implemented in H-type MFCs. The steady state cell, cathode and anode potential of MFC with using CoNPc/C were comparable to those of Pt/C., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Micrococcus glutamicus NCIM-2168 exhibited complete decolorization and degradation of C.I. Reactive Green 19A (an initial concentration of 50 mg l(-1)) within 42 h at temperature 37 degrees C and pH 8, under static condition. Extent of mineralization was determined with total organic carbon (TOC) and chemical oxygen demand (COD) measurement, showing a satisfactory reduction of TOC (72%) and COD (66%) within 42 h. Enzyme studies shows involvement of oxidoreductive enzymes in decolorization/degradation process. Analytical studies of the extracted metabolites confirmed the significant degradation of Reactive Green 19A into various metabolites. The microbial toxicity and phytotoxicity assay revealed that the degradation of Reactive Green 19A produced nontoxic metabolites. In addition, the M. glutamicus strain was applied to decolorize a mixture of ten reactive dyes showing a 63% decolorization (in terms of decrease in ADMI value) within 72 h, along with 48% and 42% reduction in TOC and COD under static condition.

Navy blue HER was decolorized and degraded within 24h by Trichosporon beigelii NCIM-3326 under static condition. In the present study, we investigated various physicochemical parameters such as agitation, temperature, pH, cell concentration, initial dye concentration and different carbon and nitrogen sources to achieve maximum dye degradation by T. beigelii. Sequentially, decolorization and decrease in the total organic carbon (TOC) of Navy blue HER by T. beigelii were measured. Among five strains T. beigelii gave the better performance on the decolorization of Navy blue HER along with a 95% TOC reduction within 24h. A significant increase in the activities of NADH-DCIP (dichlorophenolindophenol) reductase and azoreductase in the cells obtained after complete decolorization presumably indicates involvement of these enzymes in decolorization process. UV-vis, TLC, HPLC and FTIR analysis of extracted products confirmed the biodegradation of Navy blue HER. Phytotoxicity study demonstrated no toxicity of the biodegraded products with respect to plants viz. Phaseolus mungo and Sorghum vulgare. In addition to Navy blue HER, this strain also shows ability to decolorize various industrial dyes, including Red HE7B, Golden yellow 4BD, Green HE4BD, Orange HE2R, Malachite green, Crystal violet and Methyl violet.

A developed consortium-GR, consisting of Proteus vulgaris NCIM-2027 (PV) and Micrococcus glutamicus NCIM-2168 (MG), completely decolorized an azo dye Scarlet R under static anoxic condition with an average decolorization rate of 16,666 microg h(-1); which is much faster than that of the pure cultures (PV, 3571 microg h(-1); MG, 2500 microg h(-1)). Consortium-GR gave best decolorization performance with nearly complete mineralization of Scarlet R (over 90% TOC and COD reduction) within 3h, much shorter relative to the individual strains. Induction in the riboflavin reductase and NADH-DCIP reductase was observed in the consortium, suggesting the involvement of these enzymes during the fast decolorization process. The FTIR and GC-MS analysis showed that 1,4-benzenediamine was formed during decolorization/degradation of Scarlet R by consortium-GR. Phytotoxicity studies revealed no toxicity of the biodegraded products of Scarlet R by consortium-GR. In addition, consortium-GR applied for mixture of industrial dyes showed 88% decolorization under static condition with significant reduction in TOC (62%) and COD (68%) within 72 h, suggesting potential application of this microbial consortium in bioremediation of dye-containing wastewater.