Study On Monascus Species And The Pigment In Red Yeast Rice In Jinhua And The Surrounding Areas

Red yeast rice, which was known as red yeast red vinasse or red rice, has been produced and used for more than one thousand years, including Eumycophyta, Ascomycetes, Euascomycetes, Monascus. Its special functions and application in food was recorded in the ancient book Compendium of materia medica written by Shizhen Li. Red yeast rice mainly were used for the treatment of digesting food, invigorating blood circulation and curing dysentery, diarrhea, traumatic injury, etc.. According to the use and fermentation processes, red yeast rice were classified as:esterificational and functional Monascus, fermentational Monascus and pigment Monascus. The esterificational and functional Monascus are used for brewing rice wine, fruit wine and medicinal liquor; fermentatioal Monascus is widely used in fermented bean curd,pickles; pigment Monascus is used as food coloring agents. Monascus can produce a variety of metabolites, which are beneficial to the human body such as cholesterol synthesis inhibitors, antibiotics, ergosterol and traditional Chinese medicine composition. In this paper, the main characteristics of 48 kinds of red yeast rice which is collected in Jinhua and its surrounding areas were studied and Monascus from red yeast rice were isolated to obtain pure culture of Monascus strains. Then using the traditional morphological methods for observation and identification of strains of Monascus based on ITS region gene sequences and using HPLC(High Performance Liquid Chromatography) to determine the effects of different carbon source, nitrogen source on pigment Monascus fermentation. The results of the study are as following.(1)The study shows that 48 kinds of red yeast rice collected from Jinhua and its surrounding areas have some great differences in their sensory properties and physical and chemical properties. The moisture content in the samples is different, the red yeast rice samples QXYG moisture content is only 2.36%, while the water content of DY6000, CK4, CZHQ and others was higher than 10%. In addition,48 kinds of red yeast rice samples were detected and only QXZH containing lovastatin 2.71μg/mL, but all the red rice samples were detected to contain citrinin.(2)Monascus isolated from different red yeast rice have obtained 30 purified strains. The colony characteristics were observed after being cultured on the medium of MEA and CYA, and the microscopic characteristics were observed after being cultured on PDA.(3)Monascus DNA was extracted using Ezup column fungus genomic DNA Extraction Kit, and ITS-rDNA sequence was extend and sequenced. With the Blast tool in the GenBank database and sequence alignment, Monascus differences in ITS area is smaller, only analyzing gene sequence of ITS is not sufficient to distinguish from the Monascus to the species, so the method can be used for the identification of Monascus, but it’s not suitable for the identification of species.(4)In order to select the most suitable Monascus pigment through fermentation,based on the one-variable-at-a-time, three main factors, the pH, carbon source, nitrogen source were studied by L9(3)3 orthogonal experiment. Through single factor experiment and orthogonal experiment, culture of optimal fermentation was maltose 8%, ammonium nitrate 0.0144 mol/L, pH value is 4.