This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Wang, H. L. Articles by Hesseltine, C. W. Search for Related Content PubMed Articles by Wang, H. L. Articles by Hesseltine, C. W. Agricola Articles by Wang, H. L. Articles by Hesseltine, C. W.

 Previous Article  |  Next Article 

Appl Environ Microbiol. 1974 May; 27(5): 906-911
Copyright © 1974 American Society for Microbiology. All Rights Reserved.

Acid Protease Production by Fungi Used in Soybean Food Fermentation

¹ Northern Regional Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Peoria, Illinois 61604

ABSTRACT

Growth conditions for maximum protease production by Rhizopus oligosporus, Mucor dispersus, and Actinomucor elegans, used in Oriental food fermentations, were investigated. Enzyme yields by all three fungi were higher in solid substrate fermentations than in submerged culture. The level of moisture in solid substrate must be at about 50 to 60%. Very little growth of these fungi was noted when the moisture of substrate was below 35%, whereas many fungi including most storage fungi generally grow well on solid substrate with that level of moisture. Among the three substrates tested—wheat bran, wheat, and soybeans—wheat bran was the most satisfactory one for enzyme production. The optimal conditions for maximum enzyme production of the three fungi grown on wheat bran were: R. oligosporus, 50% moisture at 25 C for 3 to 4 days; M. dispersus, 50 to 63% moisture at 25 C for 3 to 4 days; A. elegans, 50 to 63% moisture at 20 C for 3 days. Because these fungi are fast growing and require high moisture for growth and for enzyme synthesis, the danger of contamination by toxin-producing fungi would be minimal.