Amylase Production and Optimisation of Culture Conditions for Some Ericoid Mycorrhizal Fungi

Abstract

Enzymes occur in all living things, hence in ericoid mycorrhizal fungi (ERM). Every species of microorganisms produce enzymes capable of hydrolyzing various substrates. Amylases are known to play a significant role in the food, brewing, detergent and pharmaceutical industries. Leohumicola incrustata, and two unidentified fungi belonging to Hyaloscyphaceae (EdRU083) and Leotiomycetes (EdRU002) were tested for their ability to produce amylases under different culture conditions that included various temperature, pH, metal ions, carbon sources and nitrogen sources in a modified Melin-Norkrans (MMN) liquid medium. Leohumicola incrustata produced 1.16 U/mg protein while EdRU083 and EdRU002 had activity of 0.81 and 0.91 U/mg protein at the same pH with corresponding biomass yields of 112.67, 125.00 and 95.33 mg/50 mL respectively. Improved enzyme activities and biomass yields were noticed when supplemented with potassium, sodium, glucose, maltose, cellobiose, tryptone and peptone while NaFe-EDTA and cobalt inhibited enzyme activity. Therefore, this study opens a new opportunity for exploring ERM fungi as potential sources of microbial enzymes for commercial purposes.