Lignocellulose Biotechnology Laboratory, Department of Microbiology, University of Delhi, South Campus, New Delhi, 110021, India.
Department of Microbiology, Mahrashi Dayanand University, Rohtak, Haryana, 124001, India.
Bioprocess Biosyst Eng. 2019 Mar;42(3):367-377. doi: 10.1007/s00449-018-2041-x. Epub 2018 Nov 23.
Production of laccase from Ganoderma lucidum RCK 2011 under solid-state fermentation (SSF) conditions was optimized using response surface methodology, resulting in an approximate eightfold increase compared to that in the unoptimized media. Further, the enzyme produced under SSF as whole fermented substrate (in situ SSF laccase) was found to be more stable than the in vitro enzyme (harvested by downstreaming processing of fermented wheat bran). Interestingly, the biobleaching potentials of both in situ and in vitro SSF laccases were comparable, saving 25% chlorine dioxide for achieving similar pulp brightness as obtained in the pulp treated chemically. The reduction in the demand of chlorine dioxide in the pulp bleaching sequence subsequently decreased the levels of adsorbable organic halogen (AOX) in the resulting effluents of the process by 20% compared to the effluents obtained from chemical bleaching sequence. Therefore, direct application of in situ SSF laccase in pulp biobleaching will be environmentally friendly as well as economical and viable for implementation in paper mills.
采用响应面法优化了灵芝 RCK 2011 在固态发酵（SSF）条件下产漆酶的条件，与未优化的培养基相比，产量提高了约 8 倍。此外，在 SSF 下作为整个发酵基质产生的酶（原位 SSF 漆酶）比体外酶（通过发酵麦麸的下游加工收获）更稳定。有趣的是，原位和体外 SSF 漆酶的生物漂白潜力相当，可节省 25%的二氧化氯，从而使纸浆的白度达到与化学处理获得的纸浆相似的水平。与化学漂白序列获得的废水相比，纸浆漂白序列中二氧化氯需求的减少导致处理后的废水中可吸附有机卤素（AOX）的含量降低了 20%。因此，原位 SSF 漆酶在纸浆生物漂白中的直接应用在环境上是友好的，在经济上也是可行的，可在造纸厂中实施。
