Physiological characteristics of a high amylase-producing Saccharomycopsis fibuligera

In order to develop a strain suitable for brewing environments, reducing production input costs, and enhancing the flavor of fermentation products, a high amylase-producing strain AMCC32244 was isolated and screened from old rice wine. This strain was identified through morphological observation and molecular biological method. The environmental tolerance, substrate utilization, enzyme production by solid-state fermentation, ethanol production by raw starch materials fermentation, and aroma of the strain were analyzed. The results showed that the selected strain was identified as Saccharomycopsis fibuligera. It could tolerate the culture conditions of ethanol volume fraction 8%, pH 3, high temperature 40 ℃, and glucose content 60%, and utilize at least 15 types of carbon sources, including xylose, raffinose, and Pullulan. It could produce glycosylase, α-amylase, cellulase, protease, lipase and other enzymes in the gluten fermentation environment, among which the glycosylase activity reached 82 539.14 U/g, α-amylase activity reached 39 904.12 U/g at 70 ℃, and the amylase activity to degrade raw starch reached 4 557.62 U/g. The strain was used for liquid fermentation of raw corn starch and could produce 32 kinds of aroma substances, among which the phenylethanol content could reach 36.34 mg/L. The strain AMCC32244 could grow in a special fermentation environment, had the potential for fermentation of various raw materials, could produce rich enzyme series, which was conducive to improve production efficiency and reduce cost, and had broad prospects in the production of gluten production and starch raw material fermentation products.