| Rhizopus, fungus of the Mucoraceae family at the puycomycetes category ,canproduce a massive amount of amylases ,liquefied enzyme ,proteinase and et cetera in itsgrowth process. The enzyme output and activeness level are directly influenced by theroot mildew quality and the surrounding elements, including temperature, cultivation time,pH value, element density, nutrition and so on .Because there is a direct relationshipbetween the spirits output and the distillery yeast quality, we found that the bad distilleryyeast quality was the main reason for the lower productivity of strong drink at Enshicity, Hubei province, where the corn is the key source of liquors. In.order to improve thequality, we separated and purified distillery yeast, sifted superior strains, tested theenzyme action condition and the selenium-bearing ability ,and the method involved:1).Determine the protease activeness level by the way of FC. 2).Determined enzyme bythe 3,5-dinitro salicylic acid.3) .Determined the activeness level of the enzyme ,whichwere cultivated at different se concentration ,and the se content was determined by themeans of flame atomic absorption spectrophotometry after a dealing with specialprocess of eluting ,collecting and drying for Rhizopus. The main results are as follows:1. By comparison on biomass, activeness level of the saccharification enzyme andliquefied enzyme among the fourteen roots mildew strains ,drawing by separating andpurifying from five distillery yeast samples which were collected from five distillery inEnshi region , we have chosen 3 strains with more superiority, i.e. ERh1123,ERh3421and ERh5131.2. The growth and the enzyme activeness level of ERh1123,ERh3421 andERh5131 strains were obviously influenced by the pH of culture medium ,thecultivation period and the selenium concentration .At the pH 4.8-pH5.2, cultivated for3d-4d, added 5%-10% ,maize meal in the culture medium ,it was able to remarkablyenhance the output of ERh1123, ERh3421, ERh5131,as well as .the enzyme activity.3.The advantages of ERh3421 were the best ,at this condition ,saccharification enzymeactiveness level reached 7.46×10~2 U/g,liquefied enzyme 4.27×10~3 U/g, proteinase3.06×10~2 U/g. When saccharifying, it was advantageous, if increasing the PH value ofstarch to 5.8 ,to enhance the vigor of the three kind of enzymes. By orthogonal tests onERH3421 strains, the activities of saccharefication enzymes and liquefied enzymes canbe increased up to a level of 9.43×103 U/g and 6.83×103 U/g respectively , andthere exist a apparently variance for enzymes activities under other conditions. The bestoption should be :pH5.2, temperature 30℃,concentration of maize meal 5%. 4.In the process of production, the temperature should be controlled , on the basis ofrequirements, at 30℃to improve the activeness level of the saccharifying enzyme andliquefied enzyme and at 26℃of protease enzyme.5.The se concentration has a direct influence on the Rhizopus for its growth andenzyme-producing activity. When it was lower than the concentricity of 80μg/ml,theRhizopus could grow well ,the activeness level of the three enzymes would also beimproving ,and the content of se-collecting for ERh3421 was higher than the other twostrains .For the corn of Enshi ,the content of se was 8.07±5.02mg/kg, which was suitablefor the Rhizopus growth and enzyme producing .When the concentration was bigger than80μg/g,the Rhizopus growth ,the enzyme activity and the ability of selenium—collectingwere obviously inhibited.
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