Monitoring of fungal biomass changed by Rhizopus oryzae in relation to amino acid and essential fatty acids profile in soybean meal, wheat and rice

Abstract

This study evaluated the effect of Rhizopus oryzae, on essential amino acids and fatty acid profile on lignocellulosic substrates soybean, wheat and rice bran. R. oryzae was isolated from crop of Brazilian south region, genetically characterized and solid-state fermentation was carried on tray reactors during 120 h/30°C. The profile of amino acids and fatty acids was conducted every 24 h by high performance liquid chromatography with fluorescence detector (HPLC-FL) and gas chromatography (GC)-flame ionization detector, respectively. Fatty acids found on rice, wheat and soybean bran biomass showed an increase in the ω3 acids (72%, 64% and 58%, respectively); however, ω6 level was not affected. Fungal biomass on soybean and wheat bran present the most complete essential amino acids profile from a nutritional point of view, increased in Val (34%), Leu (19%), Lys (6%) and Phe (2%) after 96 h of cultivation. The cultivation with R. oryzae triggers changes on essential nutrients of the agro-industrial by-products.

Keywords

• Essential nutrients
• filamentous fungi
• solid-state fermentation