窖泥中高产丁酸梭菌的筛选、鉴定及其生长耐受性研究

Screening and identification of high-yield butyric acid Clostridium sp.strain and its growth tolerance

从浓香型白酒窖泥中通过传统微生物分离手段筛选高产丁酸的梭菌,并对分离菌株进行形态学观察、分子生物学鉴定及生长耐受性分析研究。结果表明,通过发酵产物检测获得两株高产丁酸菌株,编号为AB2RH027和AB2RH033,经过菌落观察、革兰氏染色及分子生物学鉴定两株菌均为丁酸梭菌(Clostridium butyricum)。通过耐受性实验,确定菌株AB2RH027最适生长pH值为8,最适生长温度为40℃,酒精耐受性为15%vol,发酵24 h丁酸产量为5.29 g/L;菌株AB2RH033最适生长pH值为8,最适生长温度为35℃,酒精耐受性为18%vol,发酵24 h丁酸产量为5.23 g/L。该研究筛选得到的两株高产丁酸的菌株在白酒品质提升方面具有一定应用价值。

High-yield butyric acid Clostridium sp.strains were screened from the pit mud of strong-flavor Baijiu(Chinese liquor)through traditional microbial isolation method.The screened strains were studied by morphologic observation,molecular biological identification and growth tolerance analysis.The results showed that two strains AB2RH027 and AB2RH033 with high yield of butyric acid were obtained by fermentation product detection,and were identified as Clostridium butyricum by colony observation,gram stain and molecular biotechnology.Based on the tolerance experiments,the results showed that the optimal growth pH and temperature of strain AB2RH027 was 8 and 40℃,the alcohol resistance was 15%vol,and the butyric acid yield was 5.29 g/L for fermentation 24 h.The optimal growth pH and temperature of strain AB2RH033 was 8 and 35℃,and alcohol resistance was 18%vol.The yield of butyric acid was 5.23 g/L for fermentation 24 h.The two strains with high yield of butyric acid had certain application value in improving Baijiu quality.