Bafana Amit, Devi Sivanesan Saravana, Krishnamurthi Kannan, Chakrabarti Tapan
Environmental Biotechnology Division, National Environmental Engineering Research Institute, Nagpur 440 020, India.
Appl Microbiol Biotechnol. 2007 Apr;74(5):1145-52. doi: 10.1007/s00253-006-0751-5. Epub 2007 Feb 21.
In the present study, a consortium of Cardiobacterium hominis and Pseudomonas stutzeri was isolated from an effluent treatment plant of a textile industry, based on its ability to decolourise azo dyes including direct black 38 (DB38), a benzidine-based azo dye. The role of each culture in the decolourisation process was elucidated, and C. hominis was found to decolourise the dye. Although P. stutzeri could not decolourise the dye, it was found to synergistically enhance dye decolourisation activity of C. hominis by scavenging oxygen in the medium and creating an anaerobic condition (oxidation/reduction potential -440 mV), which is known to be necessary for azo dye decolourisation. Together, the cultures could decolourise 90.5% of 100 mg l(-1) DB38 within 24 h. Kinetics of DB38 decolourisation was also examined, and P. stutzeri was found to increase V (max) and K (m) of decolourisation activity of C. hominis by 3.6- and 3-fold, respectively. The study also revealed a pathway of DB38 degradation with the release of benzidine from DB38 and subsequent degradation of benzidine to 4-aminobiphenyl by the cultures.
在本研究中，基于人心杆菌和施氏假单胞菌联合体对偶氮染料（包括直接黑38，一种基于联苯胺的偶氮染料）的脱色能力，从一家纺织工业污水处理厂中分离出该联合体。阐明了每种培养物在脱色过程中的作用，发现人心杆菌能够使染料脱色。虽然施氏假单胞菌不能使染料脱色，但发现它通过清除培养基中的氧气并创造厌氧条件（氧化/还原电位为-440 mV），协同增强人心中杆菌的染料脱色活性，已知这种厌氧条件是偶氮染料脱色所必需的。这些培养物共同作用，能够在24小时内使100 mg l(-1) 的直接黑38脱色90.5%。还研究了直接黑38脱色的动力学，发现施氏假单胞菌分别使人心杆菌脱色活性的V（max）和K（m）增加了3.6倍和3倍。该研究还揭示了直接黑38的降解途径，即直接黑38释放出联苯胺，随后培养物将联苯胺降解为4-氨基联苯。
