MULTIPURPOSE UTILIZATION OF THE ASPERGILLUS ORYZAE FUNGUS - THE PRODUCER OF THE HYDROLASE COMPLEX

Abstract

The possibilities of multi-purpose use of metabolites Aspergillus oryzae 01134 under deep cultivation and residual biomass of micromycetes were investigated. By 36 h of growth of the fungus, the level of proteolytic activity (PS) in the culture fluid (CS) was 87%, and β-glucanase (GCS) – 97% of the maximum value achieved at 48 hours of growth. The results of studies of the dynamics of changes in the content of proteins and polysaccharides in the biomass of the fungus during its growth showed a decrease in their level to 48 h of growth, by 15.0; 5.0%, respectively, due to the increased activity of intracellular hydrolytic enzymes and the beginning of autolytic processes. Culture liquid was applied for filtration for biomass separation, ultrafiltration and drying to obtain a concentrated enzyme preparation (CFP). The enzyme preparation CFP with proteolytic activity of 680 u. PS/g, β-glucanase activity of -143 HLA/g, amylase activity of 764 AC/g was obtained. The content of amine nitrogen was 0.6%, crude protein – 12,8%, ODS – 18,0%.The presence of 13 major protein fractions was established by electrophoretic studies of fractional composition of CFP protein substances. The results of identification of peptide fractions showed that more than 50% of bioactive peptides with molecular weight (MM) from 15 to 40 kDa showed proteolytic activity. Peptide fractions WITH mm 57-60 kDa were characterized by the presence of β-glucanase activity. 4 peptide fractions with MM 20,9; 26,7; 35,0 and 51,4 kDa showed amylolytic activity. The results of the residual biomass study showed that it contained 20,8% crude protein, 31,0% polysaccharides (ODS), 3,3% reducing carbohydrates, 0,4% amine nitrogen and 1,6% amino acids in free form. According to the content of essential amino acids in the protein, the fungal biomass is not inferior to animal proteins, is close to the FAO/who scale and is superior to such amino acids as methionine, tryptophan (10,2 against 3,5 and 18,0 against 1,0 g/100g of protein, respectively), yielding to such amino acids as valine and leucine (3,4 against 5,0 and 4,3 against 7,0 g/100g of protein, respectively). The presence of a high amount of tryptophan and methionine in microbial biomass opens up prospects for the use of the latter to create dietary SUPPLEMENTS for functional purposes.