The Research Of Substances Which Characterize The Ageing Of Yeast

Enzyme is generally considered to be the catalyst of life activities. Enzyme plays a vital role in various life activities. The key enzymes activities in sugar metabolic processes of yeast such as glucose6-phosphate dehydrogenase, a-ketone glutaric acid dehydrogenase, isocitrate dehydrogenase, pyruvate kinase, etc.were studied duing the process of aging. At the same time, changes of the antioxidant enzyme activity and produced rate of intracellular O2-was analysed in the process of aging. Experimental research shows that:1. In the process of continuous subculture, the sugar degradation rate was dropped and Saccharomyces cerevisiae growth speed was slowed. The key enzyme activities in sugar metabolic process were higher in initial than later period.The cells form changed and cells surface have obvious fold as well as cells became flat in yeast aging process. While different algebraic yeast cell wall proteins were analyzed and protein variations were found.2. The mathematical model of yeast aging was established and k was defined. The fitting curve equation of antioxidant enzyme activity was that Y=a+bX+cX2+dX3and the produced rate of O2-was that Y=a+bX+cX2+dX3. According to antioxidant enzyme activity and produce rate of O2-., the growth process of yeast was divided into G area and the area A.3. The ion stress results show that the antioxidant enzyme activity was raised under the stree of copper and manganese.But under the stree of zinc, the enzyme activity was declined. The produced rate of O2-. significantly speeded up under the stree of the three kings of ions.It was also found that the synergy between the ion, and the most significant influence was three ion working together.