Page 289 - Demo

SECTION II. APPLIED BIOTECHNOLOGY IN THE PHARMACEUTICAL INDUSTRY... 293in functional food and pharmaceutical production in Vietnam, contributing to the sustainable development of the national microbiology and biotechnology industries.2. MATERIALS AND METHODS 2.1. Fungal strainMonascus purpureus HG12 was isolated from fermented rice, and belongs to Microorganism culture ccollection of Fermentation Department of Institute of Biotechnology, Vietnam Academy of Science and Technology. The strain was maintained on Malt extract (ME) agar and incubated at 30%u00b0C for 7 days, preserved at 4%u00b0C, and sub-cultured once every 4 weeks. 2.2. Production of red pigment by M. purpureus under solid-state fermentation conditionsSolid-state fermentation was conducted as follows: 100 grams of plain rice, red rice, and rice bran were steamed with 60 ml of tap water, achieving a moisture content of 65%. After cooling, 50 grams of the steamed rice was placed in a 500 mL Erlenmeyer flask and sterilized at 121%u00b0C for 15 minutes. Next, a 5 ml distilled water suspension from a 7-day-old PDA slope of M. purpureus strains, which had been grown at 30%u00b0C, was used for inoculation. The mixture was then cultivated at 30%u00b0C for 20 days. After fermentation, the steamed substrates, which changed in color from bright red to dark red, were dried at 60%u00b0C. Finally, the pigment was extracted and measured [6].2.3. Pigment extraction and estimation from solid culturesThe pigment was extracted according to the method described by Babitha et al [4]. Pigment yield was expressed as O.D/g dry substrate after recording the specific absorbance at 510 nm [7].