绿豆酸浆中淀粉絮凝菌的分离鉴定及其生长特性

以自然发酵绿豆酸浆为研究对象,采用平板分离技术从酸浆中分离出5株具有絮凝淀粉活性的产酸细菌,通过群体形态、个体形态观察、生理生化实验及16S rDNA序列分析对絮凝活性最高的菌株LLY11进行菌种鉴定,鉴定该菌株为Acetobacter indonesiensis,并命名为Acetobacter indonesiensis LLY11。通过单因素实验优化了其培养条件,其最佳培养条件为:分别以1%葡萄糖、2%牛肉膏作为绿豆汁培养基的碳源和氮源、初始pH5.0、培养温度30 ℃,在该培养条件下,测定了LLY11菌株的生长曲线,确定菌株从12 h才开始进入对数期,有二次生长,分别在24 h和42 h菌体数量达到最高值,随后进入衰亡期。

The isolation and growth characteristics of starch flocculating bacteria from mung bean sour liquid

By natural fermentation mung bean sour liquid as the research object,using plate screening techniques isolated five strains with starch flocculation activity of acid producing bacteria from sour liquid.By group morphology,individual morphological observation,physiological and biochemical experiments and 16S rDNA sequence analysis strain LLY11 with the highest flocculation activity were identificated.The strain was identified as Acetobacter indonesiensis and named as Acetobacter indonesiensis LLY11.The culture conditions were optimized by single factor experiments,the best culture condition was glucose 1%,beef paste 2%,initial pH5.0,culture temperature 30 ℃,under this culture condition,the growth curve of LLY11 strain was determined. It was determined that the strain began to enter logarithmic period from 12 h,appeard secondary growth and reached the highest value at 24 h and 42 h,and then entered the decline stage.