壳低聚糖高产菌的诱变选育

Selection of Chitosan-oligosaccharide High-yield Stain by Mutagenesis

[目的]探讨壳低聚糖高产菌诱变选育的方法。[方法]以壳低聚糖产生菌蓝色犁头霉ZH08为出发菌株,经紫外诱变和亚硝酸诱变处理,以对硝基乙酰苯胺为指示剂,利用双层平板颜色反应法,挑取菌落黄色比较深的脱乙酰酶高活性突变株,再经摇瓶发酵复筛,以获得壳低聚糖产量较高的菌株。[结果]通过对出发菌株ZH08进行理化诱变,获得突变株共7株(XH01～07),经过反复传代和筛选,这几株突变株的壳低聚糖含量均高于出发菌株,其中XH05菌株的壳低聚糖含量最高,其产量稳定在1.07 g/L,比出发菌株提高72.6%。[结论]利用对硝基乙酰苯胺作为筛选具较高甲壳素脱乙酰酶酶活的跟踪试剂,用于筛选壳低聚糖高产菌株,是一种快速、有效的筛选方法。

[Objective] The study aimed to discuss the method for selecting chitosan-oligosaccharide high-yield stain by the mutagenesis.[Method] With Absidia coerulea ZH08 produced by chitosan-oligosaccharide producing bacterium as the original strain,through UV and HNO2 mutagenesis treatments,taking the paranitroacetanilide as the indicator,the double-layer flat color reaction method was used to pick the deacetylase high-active mutation stains with deeper yellow colonies,and then through shake flask fermentation and complex sieving the chitosan-oligosaccharide stain with higher yield were obtained.[Result] Through the physicochemical mutagenesis on the original strain stain ZH08,7 mutation stains（XH01-07）were obtained,and through transferring over the generations and screening,the chitosan-oligosaccharide contents of these stains were all higher than that of the original strain,in which the chitosan-oligosaccharide content of XH05 was highest and its yield was stable at 1.07 g/L,being 72.6% higher than that of the original strain.[Conclusion] Using the paranitroacetanilide as the tracking indicator for screening the chitin deacetylase with higher enzymic activity is a fast and effective screening method for being used to screen the chitosan-oligosaccharide high-yield stain.