高产色素红曲菌的筛选鉴定及其液态发酵条件优化

摘要

The Monascus strain,L03,was isolated from the red kojic rice samples collected from Yongchun,Anxi, Gutian,Nanping,Sanming,and Longyan in Fujian for its high red-pigment-producing ability.Based on the morphology and molecular biology of L03,it was identified to be M.purpureus .Subsequently,single factor and orthogonal experiments were conducted to optimize the conditions for the liquid fermentation of the yeast.Color of the fermented suspension reached 1,578 U/mL when the yeast was inoculated 6% by weight into a liquid medium consisting of 8% of glycerol,1.5 % of peptone,0.1% of Mg2 SO4 ,and 0.25% of KH 2 PO4 in a loading volume of 100 mL/250 mL and incubated at 32℃ with constant agitation at the speed of 180 rpm for 9 days.%从福建永春、安溪、古田、南平、三明、龙岩等地收集的红曲米中分离筛选得到了1株高产色素红曲菌 L03,利用形态学和分子生物学的方法对其进行鉴定,结果表明为紫色红曲菌 Monascus purpureus 。同时通过单因素和正交优化试验确定了其最佳的液态发酵条件：以8%的甘油为碳源、1.5%蛋白胨为氮源、硫酸镁0.1%、磷酸二氢钾0.25%、接种量6%、发酵温度32℃、时间9 d、摇床转速180 r·min-1、250 mL 容器中装液量100 mL,在此液态发酵条件下其总色价平均值为1578 U·mL-1。