一株耐酒精纤维素分解菌的分离鉴定及生长条件研究

木薯酒精糟因其低营养高含水量而难以利用和处理,目前对新鲜木薯酒精糟主要采用机械脱水及干燥的方法,但此类方法的经济成本和能耗都较高,很难形成产业化。该实验在木薯酒精糟中通过用刚果红培养基初筛和杜博氏培养基复筛得到一株耐酒精的纤维素分解菌,编为13号。经16S rRNA序列鉴定与链霉菌同源性达99%。其最适生长pH值为6.5,最适生长温度为40℃。对酒精有一定的耐受性,能在酒精浓度为6%的环境中生长,并且在酒精浓度为1%时对菌株生长影响不大。同时该菌能在40℃的温度条件下保持良好的生长态势,对适应废物堆肥发酵后期熟化产生有益次生代谢产物有利。所以利用此菌耐酒精、产纤维素酶且较耐高温等特性,对于处理含酒精的纤维素废物具有较好的应用前景。

Screening, Identification and Culture Conditions of a Cellulosedegrading and Alcohol-stable Streptococcus

Cassava lees which is by product of fuel ethanol production is difficult to utilize and dispose due to its high moisture and little nutrition.Fresh cassava ethanol stable is mainly disposed with mechanical-dehydration-and-dry method,which is costly and energy intensive.A strain named 13th which is a cellulose-degrading and alcohol-stable was isolated from cassava lees using Congo Red medium and Dubos medium.The strain was classified and identified by 16S rRNA gene sequence analysis.Results indicated that 16S rRNA gene sequence of the strain homologized with that of Streptomyces up to 99%.Its pH value of optimal growth was 6.5,and the optimum growth temperature was 40 ℃.Streptomyces has some endurance for alcohol,even can breed in alcohol of the concentration of 6%,and there is little effect to the Streptomyces when the alcohol is 1%.The bacteria can keep a good growth under the condition of 40 ℃,which is benefit to adjust to ripen and produce the salutary secondary metabolites at the late stage of fermentation of waste composting.The strain has perspective and practicability on the treatment of waste material with alcoholic cellulose,especial cassava lees.