Production of Aspergillus oryzae RCAM 01133 biomass with increased protein and polysaccharides content using by-products of food industry

摘要

The biomass of filamentous fungi is a promising source of protein and carbohydrate. It can be used as an unconventional substrate in technologies for obtaining food and feed ingredients. The studies show that the fungus Aspergillus oryzae synthesizes an insufficient level of protein in the process of solid-state fermentation. The aim of the research was to develop conditions for the production of fungal biomass with a high content of protein and polysaccharides on the basis of solid-state fermentation using by-products of food industry as inexpensive substrate for biomass production. Wheat bran, soybean meal, distilled dry grains with solubles, and brewer’s spent grain were used as raw material. Results of fermentation show that the protein content was 73.4% and 82.0%, which is more than 3 times higher than in fungus grown by submerged fermentation. The studies of the biosynthesis properties of the selected strain A. oryzae RCAM 01133 confirmed the high biological value of microbial biomass cultivated using food by-products. Fermentation of micromycete on culture media containing soybean meal and DDGS provided an increase of protein content by 1.45 times. Maximum increase of amino acids was observed for isoleucine, leucine, tryptophan, and glutamic acid. The increased content of synthesized polysaccharides related to media containing wheat bran and DDGS. The highest concentrations of polysaccharides were 27.9% and 32.9%, respectively.