Investigation of protease biosynthesis of some molds of the genus Aspergillus.

Abstract

Aspergillus species is one of the genera widely used in many fields, especially in food processing and enzyme production. Because, Aspergillus can produce many enzymes such as amylase, invertase, protease, and pectinase. This study examined the protease biosynthesis capacity of some mold strains from the collection of the Center for Industrial Microbiology, Food Industry Institute. From 10 selected strains of Aspergillus genus, unable to produce aflatoxin after the preliminary selection process, the result exhibited 3 separate groups: 05 strains with low protein biosynthesis, 02 strains for average protease fertility, and 03 strains for high protease production. The results of the protease activity survey indicated that A. oryzae CNTP 5043 strain showed the highest protease activity at 72 hours and reached 645.6 UI/g, followed by A. oryzae CNTP 5027 with 96 hours of culture reached 535.5 UI/g, and A. oryzae CNTP 5082 reached 408.5 UI/g after 72 hours of culture. Thus, 3 strains demonstrated great potential in creating crude enzyme preparations for food processing. These strains will be selected for further study of suitable conditions for enzyme production with high activity.