| By researched the tanekoji of okara soy sauce of mutation breeding and optimized the strains that get mutational strains of starter-making process condition to improve dispase and cellulose enzyme yield, improve the utilization rate of protein of raw material, increased content of amino nitrogen, thus improved the quality of okara soy bean, avoids okara was not rational utilization of resource waste for a long time, and reduced production cost, improved the quality of soy sauce.Accordingly, with Aspergillus oryzae and Aspergillus niger for okara soy sauce tanekoji, UV and DES mutagenesis respectively, used the screening culture medium and fermentation medium to get mutation strains U2, A7. First the original strains diluted and applied on the screening culture medium, cultivated of its colonies 72h after, carries on the observation, measuring the hydrolyze circle D and the size of the colony d, the ratio was namely K. When K value is bigger, the strain screening medium corresponding enzyme production quantity was high. Inoculated the strain that got from screening medium in fermentation medium, buckle after 72h, by determined dispase or ellulose enzyme activity got a excellent original strain every strain. Then through the different time UV mutagenesis, DES mutagenesis got death rate curve, further analysis got the best mutagenesis time, positive change occurs most likely time. When Aspergillus oryzae was been UV mutagenesis 30min, DES 40min, the mutants chance to maximize the positive mutation; When Aspergillus niger was been UV mutagenesis 60min, DES 40min, the mutants chance to maximize the positive mutation. Two strains of mutants separately, each got a orthomutal strains, respectively for U2,A7, dispase and cellulose enzyme activity achieved respectively 1889 U/g,1746 U/g, the enzyme activity for the original respectively strains of 1.33 times and 1.24 times. passage U2, A7 continuous eight times,determined dispase and cellulose enzyme activity, take the average enzyme value, their enzymes activity were stable and the strains of catagenesis were not clear.Using U2, A7 been the tanekiji, respectively, proceeded single factor test and the response surface test and SAS software analysis. First, respectively, the determination of U2 and A7 24h,36h 48h,60h,72h,84h, 96h,120h, activity of the dispase and cellulose enzyme, determine their time of most production of enzyme, cultivated time of the highest enzyme for Aspergillus oryzae orthomutal strain U2 was 60h, Aspergillus niger orthomutal A7 produce cellulose enzyme was highest when for 72h. Two orthomutal strains were in bran:okara respectively for 4:1 ratio,3:1,2:1,1:1,1:2, respectively cultivated 60h,72h.Determined the activity of dispase and cellulose enzyme. When Aspergillus oryzae orthomutal strain U2 was in raw material 1:1, dispase activity was up to a maximum of 1905U/g; When Aspergillus niger orthomutal strain was in raw material ratio material 2:1 for the A7, cellulose enzyme activity achieved 1738U/g. Orthomutal strain U2 in moisture content was 40%,45%,50%,55%,60%,65%, determined of dispase actively respectively,when orthomutal strain U2 was in moisture content for 50%, the dispase activity was up to a maximum of 1937U/g; orthomutal strain A7 was in moisture content in 50%,55% 60%,65%,70%,75%,measure its cellulose enzyme activity, when orthomutal strain A7 was in water content 60%, cellulose enzyme activity was top achieved 1767U/g. orthomutal strain cultivated U2 respectively 26℃,28℃,30℃,32℃,34℃, determined dispase activity of every temperature,when orthomutal strain in cultivated temperature for 30℃, dispase activity was up to a maximum of 1978U/g; A7 orthomutal strain cultivated respectively for 26℃28℃,30℃,32℃,34℃, determined its cellulose enzyme activity, when orthomutal strain in cultivated temperature for 30℃, cellulose enzyme was top achieved 1819U/g.By single factor experiment, got the best value for the reference culture conditions, used SAS software designed response surface testing, and analyzed the test results:the best cultivation condition Aspergillus oryzae bran:okara was 1:1, Moisture content is 49.92%; Starter-making temperature for 30.15℃, considering the test actual situation, been sure material ratio was 1:1.4; water content 49.9%,the cultivated temperature for 30.2℃. Determination of dispase activity, three parallel experiments respectively was:2247.7 U/g, 2254.1 U/g,2202.4U/g. Average enzyme activity was 2234.7U/g,been the original strains 1.58 times.The best cultivation condition Aspergillus niger bran:okara was for 2.2:1; Moisture content is 59.88%; Starter-making temperature for 29.54℃. Considering the test actual situation, been sure material test ratio was; 11:10,water content 59.9%, The cultivated temperature for 29.5,000℃. Determination of cellulose enzyme activity, three parallel experiments respectively was:2117.5 U/g,1997.3 U/g,2071 U/g, Average enzyme activity was 2061.9U/g,been the original strains 1.46 times.
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