用β-紫罗兰酮筛选虾青素高产菌株

Screening Astaxanthin-hyperproducing Strains with β-ionone

用β-紫罗兰酮作为筛选剂选择性分离海洋红酵母虾青素高产突变菌株。实验结果表明,在β-紫罗兰酮存在的情况下,由于类胡萝卜素合成受到抑制,海洋红酵母的生物量和虾青素合成量都减少;当平板培养基中β-紫罗兰酮浓度达到370 mg/L时,海洋红酵母的致死率为92.3%;在这种平板培养基上涂布经甲基磺酸乙酯诱变的海洋红酵母,随机筛选200个菌落,结果表明生物量、虾青素体积产率和细胞产率均有所提高的正突变株占18%,生物量、虾青素体积产率和细胞产率的单项指标有所提高的正突变株分别占22.5%、45%和46%。该实验结果表明在分离培养基中添加β-紫罗兰酮可选择性地分离海洋红酵母虾青素高产菌株,提高虾青素高产突变株的筛选效率。

The astaxanthin-hyperproducing mutants of oceanic red yeast were efficiently screened with β-ionone.As shown by the result,the biomass and astaxanthin content of oceanic red yeast was reduced due to the presence of β-ionone which inhibited the synthesis of carotenoids.The lethality rate of oceanic red yeast would attained 92.3% if 370 mg/L of the β-ionone concentration was contained in the plate medium.The oceanic red yeast mutated by ethyl methane sulfonate was cultured on plate medium containing 370 mg/L of the β-ionone.200 mutants were randomly screened,positive mutants with increased the biomass,astaxanthin volumetric yield and astaxanthin specific yield accounted for 18% of the total strain,the mutants with higher biomass,astaxanthin volumetric yield and astaxanthin specific yield higher occupied 22.5%,45% and 46%,respectively.The results indicated that the astaxanthin-hyperproducing strains of oceanic red yeast could be efficiently isolated on the selective medium containing β-ionone.