| In this study, Eurotium cristatum were isolated and purified from Fuzhuan bricktea. Its microflora and individual shape characteristics were observed. Thesubmerged fermentation conditions of Eurotium cristatum were studied with shakeflask culture method. The optimal content of liquid culture medium and conditions ofEurotium cristatum were confirmed too. Adopt mechanical mixing fermenter, thevariations of main components of fermentative liquor during the submergedfermentation of Eurotium cristatum were investigated. In addition, the effects ofEurotium cristatum fermented solution on amylase, proteinase and lipase activitieswere studied. The results were concluded as follow:1. Eurotium cristatum isolated and purified from Fuzhuan brick tea, was inoculated onPDA culture medium. In the earlier stage of cultivation, the color of colonyperimeter is white or yellow and the inside color is slightly dark. In the later stage,colony perimeter is yellow and inside is brown. Eurotium cristatum colony ismade up of mycelium and plectomycete. The mycelium is white. Theplectomycete is yellow and like or nearly like a ball. Its diameter is 150-200μm.Plectomycete contain a lot of sporangium, which is like or nearly like a ball andits diameter is about 5μm. Plectomycete will split open and release sporangiumin a regular period.2. The optimal composition and content of culture medium are as follows: sucrose6%, dark green tea 0.8%. The optimal cultivation conditions of Eurotium cristatumthrough orthogonal designs were initial pH 5.5, Rotational speed 120r/min, culturetemperature 30℃, fermentation time 84h and inoculating amount 1%. Under the optimal conditions, the dry weight of mycelium reached 0.3992mg/100mlfermented solution.3. The growing curve of Eurotium cristatum is made up of lag phase (0～48h), thelogarithm growth phase (48～84 hours) and the stationary phase (84～120 hours).After fermented 84h, the dry weight of mycelium reached 0.3754mg/100mlfermented solution.4. PH value of the fermented liquid drops generally during the fermentation. It dropsslowly in 0～36 hours, from 5.51 to 4.76. PH value drops fast in 36～48 hours,from 4.76 to 4.05. PH value begins to go up in 48～96 hours, from 4.05 to 5.04. PHvalue tends towards stability from 96 hours to 120 hours, and it is about 5.00.5. The contents of tea polyphenols and catechins decrease fast and the content of teapigments is rising constantly during the fermentation. The content of teapolyphenols decreases to 48.935mg/100ml from 123.726mg/100ml and thecontent of catechins reduces by 73.68%. There is a little content of TF Infermentation solution, and it increases a little in initial 24 hours and decreasesgradually afterwards. TF can't be examined out at the 96th hour. In the first 84hours the content of TR increases, then it turns to decrease gradually. The contentof TB increases during the fermentation, increases slowly in earlier stage,increased very fast after 72 hours.6. The content of Amino acid during the fermentation changed from 8.340mg/100mlto 1.756mg/100ml, decreases by 78.9%.7. In simulated gastric, fluid Eurotium cristatum fermented solution could promotethe activities of gastric proteinase and inhibit the activity of lipase, the activities ofgastric proteinase increase to 1.59 times and the activity of lipase reduced by46% compared with the control. In simulated intestinal fluid, the activities ofgastric proteinase andα-amylase increase to 3.45 and 3.98 times compared withthe control, but activity of lipase reduced by 14%.
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