1 株产吲哚乙酸菌株的鉴定及发酵条件优化.

A strain HS5B5 producing indole-3-acetic acid was identified by morphological observation, physiological and biochemical tests and 16S rDNA sequence analysis. The medium composition and fermentation conditions of strain HS5B5 were optimized by single factor and orthogonal test. The results showed that the strain HS5B5 was Bacillus subtilis. The optimized medium composition and fermentation conditions were mannitol 5.0 g/L, beef extract 7.5 g/L, calcium chloride 2 mmol/L, inoculum 6%, pH value 7.3, temperature 28 ℃ and liquid content 30 mL, respectively. The content of indole-3-acetic acid in the fermentation broth of strain HS5B5 after optimization was (108.90±1.10) mg/L, which was 183.08% higher than that before optimization. The research results enrich the resources of microbial strains and provide technical support for large-scale production. [ABSTRACT FROM AUTHOR]