Studies On Mutation And Effects Of Physico-chemical Properties Saccharomyces Cerevias Under High Pressure

In this paper, Saccharomyces rouxii was treated by high pressure at the pressure of 0.1-400MPa within 20 mins. Studied effects of high pressure on death radio, physico-chemical properties of Saccharomyces rouxii. And an excellent strain was induced and screened by high pressure. The result showed that: High Pressure obviously influence the death radio and physico-chemical properties of Saccharomyces rouxii. In addition, a perfect variation strain HP300a was screened at the pressure of 300MPa redution deacetyl capacity of strains,the yeast speed is quick, the yeast death speed is very low,the taste is good and some main indexes of beer are also better than strain without pressure treated. The original strain Saccharomyces rouxii and high pressure induced strain HP300a subjected RAPD(random amplified polymorphic DNA) and ISSR(inter simple sepuence repeats) analysis.Results showed distinct polymorphic ,84.44% and 73.22% respectively. ISSR analysis indicated that the mean absolute distance coefficient between the original cultivar and the Mutant 1 is 0.553.RAPD analysis demonstrated that the mean absolute distance coefficient between the original cultivar and the Mutant 1 is 0.750. Results indicated that it is possible to obtain stable Saccharomyces rouxii mutants, include both genetic and epigenetic changes, by high pressure treatment. It provided theoretic evidences to high-pressure induced Saccharomyces rouxii mutants. High pressure seems an efficient approach for mutagenesis.