Nutritional and Antioxidant Values of Oyster Mushroom (P. sajor-caju) Cultivated on Rubber Sawdust

Abstract— Grey oyster mushroom (Pleurotus sajor-caju) is one of the edible mushrooms from Pleurotus family, which is cultivated commercially in Malaysia. The global mushroom market has shown remarkable growth in recent years and has attractive market potential for the future. This study aimed to determine nutritional value and antioxidant properties of fresh grey oyster mushroom (Pleurotus sajor-caju) with the intention to give better information on nutritional composition of fresh oyster mushroom cultivated on rubber sawdust. Grey oyster mushrooms were freshly harvested from Teloi Agro Farm, Kedah, Malaysia. The proximate analysis was used to determine nutrient composition of grey oyster mushroom. Highest nutritional value of grey oyster mushroom is the moisture content (90.10±0.09%), followed by crude fibre content (17.27±1.08%), protein content (4.00±0.31%), carbohydrates content (3.54±0.09%), while the lowest nutritional value was possessed by fat content (1.18±0.33%) and ash content (1.16±0.02%). The antioxidant activities of the mushroom were measure using total phenolic content (TPC) by Folin-Ciocalteu reagent method and 2, 2-diphenyl-1-picrylhydrazyl radical scavenging (DPPH) assay. The hot water extract showed mushroom powder possessed 2.21±0.03 mg GAE/g of dried mushroom powder for total phenolic content and at concentration of 0.1g/ml it can inhibit 89.29% of DPPH radicals. By virtue of having high fibre with low fat and high antioxidant activity, grey oyster mushroom can be considered as a functional food, which can provide health benefits.