ABSTRACT

Microbial treatment of natural fibers is a preferred alternatives in ramie degumming process as compared to conventional chemical degumming technology with alkaline treatment at high temperature. Usually, it is difficult to degrade the noncellulosic components of ramie bast completely with a single strain in the mono-culturing degumming system. Microbial coculture strategy has been widely used in biotechnology, especially in the degradation of biological materials. In the present study, five strains for ramie degumming were identified as Dickeya dadantii strain DCE-01, Bacillus subtilis strain 1101, Bacillus sp. B6, Bacillus cereus strain B7, and Bacillus cereus strain B8 by sequencing of 16 S rRNA genes. Enzymatic activities characterization, ramie degumming experiments with mono-culturing systems, and the evaluation of strain compatibility showed that group DCE-01/B7 were the most suitable pairs for the construction of bacterial coculturing system. After preliminary optimization of coculturing fermentation condition, the weight loss weight ratio of ramie fibers was 27%, which was increased 13.6% and 8.9% while compared to mono-culturing systems of strain B7 and DCE-01 respectively. These data highlighted the benefit of microbial coculture strategy in the application of ramie degumming process, and indicated a higher-efficiency alternative for the microbial degumming in the textile industry.

摘要

与传统的高温碱处理化学脱胶技术相比，天然纤维的微生物处理是苎麻脱胶工艺中的优选替代方案。通常，在单培养脱胶系统中，单株很难完全降解苎麻韧皮的非纤维素成分。微生物共培养策略已广泛应用于生物技术，尤其是生物材料的降解。在本研究中，5株用于苎麻脱胶的菌株被鉴定为Dickeya dadantii菌株DCE-01、枯草芽孢杆菌菌株1101、芽孢杆菌。B6、蜡状芽孢杆菌菌株 B7 和蜡状芽孢杆菌菌株 B8 通过对 16 个 S rRNA 基因进行测序。酶活性表征、苎麻脱胶单培养系统实验和菌种相容性评价表明，DCE-01/B7组是最适合构建细菌共培养系统的配对。经初步优化共培养发酵条件后，苎麻纤维失重率为27%，与菌株B7和DCE-01的单一培养体系相比，分别提高了13.6%和8.9%。这些数据突出了微生物共培养策略在苎麻脱胶工艺应用中的优势，并表明了纺织行业微生物脱胶的更高效率替代方案。