| Monascus is attractive by its capacity of abundant natural monascus pigment producing. In recent years, it was also found that Monascus produce some functional substances, such as y-aminobutyric acid and Monacolin K, which can reduce blood pressure & cholesterol, prevent and cure some other diseases. In this paper, y-amino-butyric acid was determined by pre-column derivatization capillary electrophoresis method; High-yielding y-aminobutyric acid monascus strains were screened by complex physical and chemical mutagenesis; Morphological and physiological characteristics of wuyi monascus ZL307 were both studied. Additional, the fermentation conditions of the mutant was optimized by response surface method. Finally, the preliminary extraction for y-aminobutyric acid from fermentation broth and the application of monascus to vintage were studied.The y-aminobutyric acid was quantified by pre-column derivatization capillary electrophoresis method. The optimal seperation effect was achieved when using phenyl isothiocyanate (PITC) as pre-column derivatization reagent and 80 mmol·L-1 of borax (pH9.5) running buffer,25 KV of separation voltage at 20℃with 250 nm of detection wavelength. Under above conditons, the standard curve showed the excellent linerar relationship within the range of y-aminobutyric acid from 15.625μg·mL-1 to 500μ·mL-1. The linear equation was Y=2808.9X-6613.9(r=0.9996)and the average recovery of the sample was more than 99.9%.The high-yielding y-aminobutyric acid monascus strain ZL307 was screened by complex UV and 5-fluorouracil protoplast mutagenesis. Response surface method was used to optimize the fermentation conditions of mutagenic strain ZL307. The optimal conditions were:6.4% of rice flour, 0.5% of peptone,0.23% of K2HPO4,0.1% of MgSO4, at the initial pH 5.4 and,35℃with shaking at 160r/min. The verified experiments indicated that the actual average value (595.1mg·L-1) was close to predicted value which was improved more than 90% over the pre-mutagenic strain.Observed under the microscope and electron microscopy, Wuyi Monascus ZL307 was confirmed to be two kinds of reproduction styles: sexual reproduction and asexual reproduction, and its mycelium appeared cross-linking. The colony morphology of monascus were different form each other when plated on PDA medium, Czapek medium and wort medium respectively. The colony with depper color was grown on wort medium. The initial mycelium was white and radial extension towards the external. Glycolysis tests of monascus indicated that glucose, maltose, sucrose, lactose, galactose and mushroom sugar were avaliable but not myo-inositol and dulcitol. Starch hydrolysis test proved that monascus can hydrolyze starch and produce amylase. Urease test and nitrate reduction test were positive. The enzymes secreted by Monascus were wide, and expecially the glucoamylase and protease activity were preponderant.The preliminary isolation of y-aminobutyric acid from fermentation broth was studied by silica gel GF254 thin-layer chromatography. The better result for y-aminobutyric acid was obtianed with developing agent (95% of ethanol and 25% of ammonia,4:1 of volume ratio)and alcohol solution of 0.2% ninhydrin as a chromogenic agent. The spots was eluted with copper sulfate and ethanol (2:38, V/V) after scraped from the chromatography plate. The extraction rate was up to 76.4% when extracted with deionized water after dried at low-temperature. The optimal condition for red yeast rice wine was as following:25g of glutinous rice,50mL of water,5mL of inoculum, and cultivated at 25℃with 5.0 of initial pH for 8 d. Fermented red-yeast-rice-wine appeared bright, uniform, mellow and soft wine quality, no taste of uncooked rice; Physical and chemical indicators of alcohol, acidity and sweetness satisfy the public taste.
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