酵母突变株最优富硒发酵条件的研究

目的]明确酵母突变株的最优富硒条件。方法]以经紫外线诱变筛选所得的突变酵母菌为出发菌种,采用培养时间、发酵培养基中硒浓度、接种量的单因素试验,研究最优富硒条件。结果]发酵初期酵母中的硒含量随培养时间的延长逐渐增加,培养35h时,酵母中的硒含量最大。随着培养基中硒浓度的增加,酵母菌的生物量呈减少趋势,硒含量呈增加趋势。综合考虑确定培养基中硒浓度为20μg/ml。随着接种量的增加,富硒酵母的产量逐渐增大,接种量为20%时有所下降,接种量10%时硒含量最大。结论]突变酵母菌最优的富硒条件是发酵培养时间35h,培养基含硒量20μg/ml,接种量10%,此时生物量提高了58.00%,硒含量提高了74.87%,达1343mg/kg。

Study on the Optimum Conditions of Selenium-enriched Fermentation by Mutant Yeast Strains

Objective] The research aimed to confirm the optimum conditions of selenium-enriched mutant yeast strains. Method] With the obtained mutant yeast strains screened by ultraviolet radiation as the initial strains, culture time, selenium concentration in the fermentation medium and the inoculation amount were used in a single-factor test to study the optimum selenium-enriched conditions. Result] Selenium content in the yeast in early fermentation stage was gradually increased with the prolonging of culture time and selenium content in the yeast was most after culturing 35 h. With the increasing of selenium concentration in the medium, the yeast biomass showed a decreasing trend and selenium content showed an increasing trend. Considering synthetically, selenium concentration in the medium was confirmed as 20 μg/ml. With the increment of the inoculation amount in the medium, the yield of selenium-enriched yeast was gradually increased. When the inoculation amount was 20 %, it was decreased. When the inoculation amount was 10 %, selenium content was most. Conclusion] The optimum selenium-enriched conditions by mutant yeast strains were as follows: the time of fermentation culture was 35 h, selenium content in the medium was 20 μg/ml and the inoculation amount was 10 %. Under these conditions, the biomass increased by 58.00 %, selenium content increased by 74.87% and reached 1 343 mg/kg.