紫外线诱变选育高产醋酸的醋酸菌研究

Study on Breeding of Mutants of High-yield Acetic Acid bacteria by Ultraviolet Radiation

【目的】选育适合酿造杏渣醋的高产醋酸的醋酸菌株。【方法】对初始醋酸菌C1-0的生长曲线进行测定,对处于对数期的C1-0进行紫外线诱变,使诱变菌株的致死率达85%～90%,以产酸量为指标,选育高产醋酸的醋酸菌菌株,通过初筛和复筛,选育高产醋酸的醋酸菌菌株,并将其进行传代培养,测定产酸的稳定性。【结果】采用紫外线对培养至24 h的初始菌株C1-0照射20 s,使其致死率达到88.72%,获得了3株高产醋酸的醋酸菌突变株C1-11、C1-27、C1-30,产酸量分别达到37.29、38.80和36.60 g/L。这3株突变株传代5次,产酸量变化幅度较小。【结论】通过紫外线诱变的方法获得三株高产醋酸的醋酸菌株C1-11、C1-27、C1-30,比初始菌株C1-0产酸量分别提高4.5%、8.6%、2.6%,且遗传稳定性较好。

[ Objective] The purpose of this study was to breed acetic acid bacteria with high - yield acetic acid for brewing vinegar from apricot dregs. [ Method ] The growth curve of acetic acid bacteria C1-0 was determined, then the strain of C1-0 was mutated by ultraviolet irradiation. And the lethal rate of mutants was set 85% - 90%, The high - yield strains of acetic acid bacteria were screened. By means of the experiments of determining both pH value and acid content, the acid production for 5 generations of mutants was measured. [Result] The strain of C1-0 was irradiated for 20s by UV when it came into logarithmic growth phase after it was incubated for 24 h, and, the lethal rate was 88.72%. Three high - yield mutants of C1 -n, C1-27 and C1-30 have been obtained. The acid yield of C1-11, C1-27 and C1-30 were 37.29, 38.80 and 36.60 g/L respectively. The acid yield for 5 generations of mutants changed little . [ Conclution ] The mutants C1-n ,C1-27 ,C1-30 with high -yield acetic acid by ultraviolet radiation were obtained, the acid yield of C1-11, C1-27 ,C1-30 were increased by 4.5%, 8.6%, 2.6% than C1-0 ,and genetic stability was good.