窖泥己酸菌的分离培养与诱变选育

Research on Caproic Acid Bacteria Isolation from Fermentation Pit Mud and Its Induced Mutation Breeding

泥窖己酸菌产生的己酸是浓香型大曲酒主体香成分的前体物质之一。从老窖泥中分离纯化出一株产酸能力较高的己酸菌GS5,以其为亲株,通过紫外诱变(照射功率15W,照射距离30cm,时间为3m in),筛选到1株产酸量提高12%的突变株GSUT3,多次继代培养结果表明其产量稳定。研究还发现GSUT3与亲株之间,GSUT3第1代与第8代之间,其生长变化规律和己酸产量的变化规律表现一致。

Caproic acid is one of the major aromatic component precursor of Luzhou-flavor liquor.A high caproic acid-producing strain GS5 was screened from the old cellar mud by means of isolation and purification.Then,GS5 was used as the initial strain,by means of mutation under the ultraviolet radiation treatment with the power of ultraviolet lamp being 15 W,exposure distance being 30cm and exposure time being 3min.A mutant strain GSUT3 was screened with the yeild being 12% higher than that of the original one.The higher caproic acid-producing ability of the mutant was inherited after several subcultures.And the growth principles of strains and the change rules of acid-producing were detected to be coincident between the mutant strain GSUT3 and the original one,as well as between the first generation and the eighth one of GSUT3.