酵母菌受胁迫条件影响积累SOD的研究

Study on the Effect of Stress Conditions on S.cerevisiae Accumulating SOD

把引起植物生长异常变化的环境胁迫这一概念引入到酵母菌的培养过程。通过人为模拟胁迫条件(氮源、Cu2+和Zn2+、培养温度和pH值等异常,以正常值为对照)探索其对酵母菌生物量及应激产物SOD酶活力的影响。结果表明,氮源胁迫(以蛋白胨2倍添加为例)时,酵母菌体细胞生长优势明显,但SOD酶活力相反,最大时相差约30%左右;Cu2+和Zn2+胁迫对生物量影响不明显,但培养12 h左右,SOD酶活力迅速达到最高峰221U/g,表明菌体细胞对此胁迫条件迅速产生应激反应;低温胁迫(20℃)培养可促使SOD酶活力达到约105 U/g,而生物量相对偏低;pH值胁迫(pH2.0和pH5.0)均可降低SOD的酶活力,但对生物量的影响则不同。

For the first time, the concept of environmental stress conditions, causing plant abnormal growth changes, was introduced into the yeast cultivation process. By artificially simulated stress conditions （nitrogen, Cu2＋ and ZB2＋ , incubating temperature and pH Value, etc. other abnormalities, normal value as the control case） , effects on the yeast S. cerevisiae biomass and the stress product of SOD enzyme activity were explored. The results showed that：nitrogen stress （in peptone double addition, for example） had obvious advantages on yeast cell growth, but the SOD enzyme activity decreased at 30% maximum; Cu2＋ and Zn2＋ stress condition did not significantly affect biomass,while SOD enzyme activity rapidly reached the peak of 221U/g after incubating around 12 h. It showed yeast cells gave quick response to the stress conditions; low incubating temperature stress （20℃） could promote SOD enzyme activity of about 105U/g, while the biomass is relatively low; pH value of stress （pH 2.0 and pH5.0） could reduce the enzyme activity of SOD, but the impact on yeast biomass is different.