Nutritional and Bioactive Compounds: Evaluation of Pleurotus pulmonarius (Fries) Quel. Fruit Bodies Grown on Different Wood Logs in Abia State, Nigeria

Abstract

This study was conducted to determine the nutritional and bioactive compounds composition of Pleurotus pulmonarius fruit bodies cultivated on tree logs of Dacryodes edulis, Mangifera indica and Treculia africana. Pure mycelium culture of P. pulmonarius was aseptically bulked in sorghum grains. Logs were cut into average length of 18 cm with inoculation holes of 3 cm × 15 mm diameter; using high speed drill (HSD) of 5 drill bit and allowed to decompose for 8 months. During mushroom cultivation, logs were soaked in tap water for 24 hrs and pasteurized at 80°C in an improvised metallic drum (IMD) for 1 hour; using cooking gas as heat source and allowed to cool overnight. 10 g of grain based spawn was inserted into 2/3 of each hole by way of inoculation and sealed with sterile polybag for mycelium incubation. Polybags were cut open after spawn run following primordial initiation. Fruit bodies were harvested at maturity, sundried ground and packed in airtight container prior to further analysis. Data was analysed using Analysis of Variance (ANOVA) and mean separation by Duncan Multiple Range Test (DMRT) while levels of significance were determined at 5%. Results indicate that P. pulmonarius fruit bodies harvested from various tree logs were significantly different p<0.05 in their nutritional and bioactive compounds composition. Fruit body samples were rich in protein, carbohydrates, Na, K, and Ca. It was also observed that fruit bodies contained significant amount of Alkaloids, Tannins and Saponins; and could be useful in drug synthesis. Therefore adopting this technique in oyster mushroom cultivation would lead to more jobs creation and food security; but this must be done with careful regulations to avoid indiscriminate falling of trees.