Stain removing, juice-clarifying, and starch-liquefying potentials of amylase from Pleurotus tuberregium in submerged fermentation system

Abstract

Background: Amylase is used commercially in food, textiles, sugar syrup, paper, and detergent industries. Bacteria and fungi remain a significant source of industrial enzymes. Pleurotus tuberregium is a macro-fungi that can exist as a fruiting body, sclerotium, mycelium, and spores. Some studies have been conducted on this fungus, with minimal studies on its enzyme activity (s) using the submerged fermentation technique. Results: The purified amylase has a specific activity of 5.26 U/mg, total activity of 189.20 U, maximally active at 70 °C, pH of 5, and retaining 100% of its activity at 30 oC for 4 min. P. tuberregium amylase showed optimal activity with plantain peel, followed by starch and pineapple peel (42, 30, and 29 μg/mL/min respectively). The presence of Ca2+, Mg2+, and Na+ ions in the reaction mixture activated the enzyme activity, but was slightly and moderately inhibited by KCl and Na2H2PO4 respectively. The crude enzyme effectively clarified juice, liquefied soluble cassava starch (with a release of appreciable glucose quantity), and partially de-stained white fabric. Conclusions: The amylase obtained from the submerged fermentation of Pleurotus tuberregium has potential applications in food and detergent industries.