title: A low-cost wheat bran medium for biodegradation of the benzidine-based carcinogenic dye Trypan Blue using a microbial consortium.
abstract: Environmental release of benzidine-based dyes is a matter of health concern. Here, a microbial consortium was enriched from textile dye contaminated soils and investigated for biodegradation of the carcinogenic benzidine-based dye Trypan Blue using wheat bran (WB) as growth medium. The PCR-DGGE analysis of enriched microbial consortium revealed the presence of 15 different bacteria. Decolorization studies suggested that the microbial consortium has high metabolic activity towards Trypan Blue as complete removal of 50 mg∙L-1 dye was observed within 24 h at 30 ± 0.2 °C and pH 7. Significant reduction in TOC (64%) and COD (88%) of dye decolorized broths confirmed mineralization. Induction in azoreductase (500%), NADH-DCIP reductase (264%) and laccase (275%) proved enzymatic decolorization of dye. HPLC analysis of dye decolorized products showed the formation of six metabolites while the FTIR spectrum indicated removal of diazo bonds at 1612.30 and 1581.34 cm-1. The proposed dye degradation pathway based on GC-MS and enzyme analysis suggested the formation of two low molecular weight intermediates. Phytotoxicity and acute toxicity studies revealed the less toxic nature of the dye degradation products. These results provide experimental evidence for the utilization of agricultural waste as a novel low-cost growth medium for biodegradation of benzidine-based dyes, and suggested the potential of the microbial consortium in detoxification.
authors: Department of Environmental Engineering, Konkuk University, Seoul 143-701, Korea. harshadlade@gmail.com.
authors: Harshad
authors: H
authors: Lade
authors: Department of Environmental Engineering, Kyungpook National University, Daegu 702-701, Korea. avikadam2010@gmail.com.
authors: Avinash
authors: A
authors: Kadam
authors: Department of Environmental Engineering, Konkuk University, Seoul 143-701, Korea. dibypaul@live.com.
authors: Diby
authors: D
authors: Paul
authors: Department of Biochemistry, Shivaji University Kolhapur 416004, India. spg_biochem@unishivaji.ac.in.
authors: Sanjay
authors: S
authors: Govindwar
mesh_terms: D001673:Biodegradation, Environmental; D002273:Carcinogens / Q000378:metabolism* / Q000633:toxicity; D002851:Chromatography, High Pressure Liquid; D004396:Coloring Agents / Q000378:metabolism* / Q000633:toxicity; D004043:Dietary Fiber / Q000382:microbiology*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D059013:Microbial Consortia; D014343:Trypan Blue / Q000378:metabolism* / Q000633:toxicity
chemical_list: D002273:Carcinogens; D004396:Coloring Agents; D004043:Dietary Fiber; D014343:Trypan Blue