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G Degradation of Sulfonated Azo Dyes by the Purified Lignin Peroxidase from Brevibacillus laterosporus MTCC 2298^Äëíê~Åí= Lignin peroxidase (EC 1.11.1.14) was purified from the _êÉîáÄ~Åáääìë=ä~íÉêçëéçêìë MTCC 2298 by ion exchange chromatography. The K m value of the purified lignin peroxidase (using n-propanol as substrate) was 1.6 mM. The MW of purified enzyme determined with the help of MW-standard markers was approximately 205 kDa. Purity of the enzyme was confirmed by native polyacrylamide gel electrophoresis (PAGE) and the activity staining using a substrate L-DOPA. Sulfonated azo dyes such as Methyl orange and Blue-2B were degraded by the purified lignin peroxidase. Degradation of the dyes was confirmed by HPLC, GC-MS, and FTIR spectroscopy. The mainly elected products of Methyl orange were 4-substituted hexanoic acid (m/z = 207), 4-cyclohexenone lactone cation (m/z = 191), and 4-isopropanal-2, 5-cyclohexa-dienone (m/z = 149) and for Blue-2B were 4-(2-hexenoic acid)-2, 5-cyclohexa-diene-one (m/z = 207; M − 1 = 206) and dehydro-acetic acid derivative (m/z = 223). © KSBB

Aims:  To evaluate the potential of Brevibacillus laterosporus MTCC 2298 for the decolourization of different textile azo dyes including methyl red, mechanism of biotransformation and the toxicity of products. Methods and Results:  Brevibacillus laterosporus showed decolourization of thirteen different azo dyes including methyl red. Decolourization of methyl red was faster (93% within 12 h) under static condition at the concentration 0·2 g l−1. Induction in the activities of lignin peroxidase, laccase, aminopyrine N‐demethylase, NADH‐DCIP reductase and malachite green reductase was observed in the cells obtained after decolourization. Fourier transform infra‐red spectral analysis of products indicated conversion of methyl red into secondary aryl amines and nitrosamines, which further transformed into the aromatic nitro compounds. Gas chromatography–mass spectroscopy analysis suggested conversion of methyl red into high molecular weight complex derivatives. The heterocyclic substituted aryl amine (m/z 281), p‐(N,N di formyl)‐substituted para‐di amino benzene derivative (m/z 355) and p‐di‐amino benzene derivative (m/z 282) are the mainly elected biotransformation products. Microbial and phytotoxicity studies suggested nontoxic nature of the biotransformation products. Conclusions:  Brevibacillus laterosporus has potential for the decolourization of different textile azo dyes. Significance and Impact of the Study:  Brevibacillus laterosporus decolourized different azo dyes including methyl red and can be utilized for textile dye decolourization.

Brevibacillus laterosporus MTCC 2298 was screened for the decolorization of eight triphenylmethane dyes. Decolorization of malachite green was found to be fastest (87% within 3 hours, at the concentration 0.1 g/L) among the screened dyes. Various triphenylmethane dyes showed differential induction patterns of the dye-degrading enzymes. The activities of the laccase, nicotinamide adenine dinucleotidedichlorophenolindophenol reductase (NADH-DCIP reductase), malachite green reductase, and aminopyrine N-demethylase were increased in the cell-free extract obtained after decolorization of malachite green. Fourier transform infrared spectral analysis indicated formation of N-demethylated products, including primary and secondary aryl amines. High-performance liquid chromatography analysis confirmed the transformation of malachite green into new metabolites rather than its reduced form, leucomalachite green. Gas chromatography-mass spectroscopy analysis detected new degradation products, such as reduced tetradesmethyl leucomalachite green (m/z 283) and [4-(1-cyclohexyl)-(1'-phenyl)-methyl]-2, 4-hexenoic acid (m/z 282). Complete decolorization of malachite green also was observed by the partially purified laccase from B. laterosporus. Water Environ. Res., 81, 2329Res., 81, (2009.

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This study was conducted to isolate microorganisms from the gut of the marine turban shell, Batillus cornutus, which inhabits the mainland of South Korea and primarily feeds on brown algae. We were interested in isolating such gut bacteria by considering their potential to produce the polysaccharidases required for digestion of brown seaweeds and isolated three different bacteria from the gut of Batillus cornutus. The isolated bacteria were identified as Bacillus sp. JMP-A, Bacillus sp. JMP-B and Staphylococcus sp. JMP-C. The organisms were evaluated for their ability to produce polysaccharidases such as cellulase, alginate lyase, laminarinase and kelp-lyase. Bacillus sp. JMP-A and Bacillus sp. JMP-B showed a clear zone of CMC hydrolysis with a radius 1.10 (±0.057) and 3.88 cm (±0.088), respectively, whereas Staphylococcus sp. JMP-C showed no zone of CMC hydrolysis. SEM analysis confirmed that the ability of the bacterial isolates to degrade kelp differs and is correlated with kelp-lyase production. The cell free extract of the Bacillus sp.JMP-A isolate showed the highest activities of CM-cellulase, α-cellulase, laminarinase and kelp-lyase, which were 22.76, 27.10, 66.59 and 64.36 U/mg, respectively. Meanwhile, the amount of sugars released was higher during the saccharification of kelp by dialyzed intracellular enzymes of the bacterial isolates than when dialyzed extracellular enzyme was used. Experimental results of dialyzed enzymatic saccharification of the kelp demonstrated that use of partially purified enzymes was effective for glucose production.