Screening, identification and culture conditions of a cellulose-degrading 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.