http://nopr.niscair.res.in/handle/123456789/1098 Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/1305 Title: Decolorization and detoxification of textile dyes and black liquor by laccase of Cyathus bulleri <br/> <br/>Authors: Salony; Mishra, S <br/> <br/>Abstract: A number of direct, vat, basic and other (Ranomill yellow and Texacid fast red A) dyes have been decolorized using concentrated culture filtrate and purified laccase of white-rot fungus Cyathus bulleri. Decolorization (>50%) was achieved in 2-9 days using culture filtrate and this time was significantly reduced with purified laccase of high specific activity (4022 U/mg protein). Addition of ABTS {2, 2’-azinobis (3-ethylthiazoline-6-sulfonate)}, a known mediator of laccase, resulted in further reduction of time to a few hours with decolorization rates from 260 mg l-1 day-1 to 665 mg l-1 day-1. Spectral analysis indicated decrease in dye concentration with no accumulation of light absorbing aromatic materials. Decolorization was accompanied by detoxification, as shown in growth inhibition experiments with Bacillus subtilis. Addition of fungal mycelium to suitably diluted black liquor resulted in significant (60-80%) reduction in color in 3-4 days indicating suitability of this fungus for treatment of paper mill wastes. <br/> <br/>Page(s): 684-688 http://nopr.niscair.res.in/handle/123456789/1304 Title: Microbial solubilization of heavy metals from soil using indigenous sulfur oxidizing bacterium: Effects of sulfur/soil ratio <br/> <br/>Authors: Nareshkumar, R; Nagendran, R; Parvathi, K <br/> <br/>Abstract: Present study assesses efficiency of bioleaching to decontaminate heavy metal laden soil affected by tannery effluent employing sulfur oxidizing bacterium, Acidithiobacillus thiooxidans. Concentrations of predominant heavy metals were Cd, 9; Cu, 95; Cr, 11800; Pb, 85; and Zn, 238 mg/kg. Irrespective of sulfur/soil ratio (0.14, 0.21, 0.29, 0.43 and 0.57), pH dropped from near neutral to below 1 over a period of 28 days; drop in pH was rapid when the ratio was 0.57 and it took only 6 days for pH to drop from 7.12 to 0.94. Production of sulphate (22-45 g/l) increased with rise in sulfur/soil ratio. Solubilization of heavy metals was: Cd, 44-57; Cu, 60-92; Cr, 72-81; Pb, 39-56; and Zn, 55-94%. <br/> <br/>Page(s): 680-683 http://nopr.niscair.res.in/handle/123456789/1303 Title: Effect of pH on chromium biosorption by chemically treated Saccharomyces <br/> <br/>Authors: Parvathi, K; Nagendran, R; Nareshkumar, R <br/> <br/>Abstract: The effect of initial pH on biosorption by Saccharomyces cerevisiae of total chromium present in tannery effluent was investigated. Maximum biosorption efficiency was evident at neutral pH with a metal removal efficiency of 99 %. S. cerevisiae was then pretreated with NaOH and HCHO-HCOOH to study the role of proteins and amino acids, respectively, in biosorption. At pH 7, 9 and 11, biomass pretreated with NaOH exhibited significant biosorption as compared to raw biomass and that treated with HCHO-HCOOH. However, trend reversed at pH 2. At pH 4, untreated biomass exhibited maximum chromium sorption, when compared to that treated with NaOH and HCHO-HCOOH. <br/> <br/>Page(s): 675-679 http://nopr.niscair.res.in/handle/123456789/1302 Title: Landfill bioreactor: A biotechnological solution for waste management <br/> <br/>Authors: Swati, M; Karthikeyan, O P; Joseph, Kurian; Nagendran, R <br/> <br/>Abstract: This paper presents a pilot-scale investigation on landfill reactors (diam 1.3 m, height 3 m) loaded with municipal solid waste (MSW). The reactors were operated with and without leachate recirculation to simulate bioreactor fill and conventional open fill, respectively. Strong leachates with high COD (98 g/l), BOD (33 g/l), DOC (35 g/l) and TVA (34 g/l) were encountered during the first week of operation. Reduction in organic contents, BOD, COD (88%) and DOC (88%), and solids were evident in the leachates from bioreactor as against the leachates from conventional open fill. Thus, landfill bioreactor technology is a viable approach to treat organically rich MSW generated in Indian cities. <br/> <br/>Page(s): 670-674