Developing Technologies for Integration of Mushroom Pleurotus Sp. Cultivation With Production of High Value Products From Mushrooms and Fruit Post Harvest Wastes

Abstract

Increasing global population has led to an increase in demand for fruits, resulting in massive generation of fruit processing and post-harvest wastes. The current study thus developed technologies for fruit waste utilization in the production of value-added products. Our findings found that growing mushrooms on fruit peel significantly impacted on growth, yield, and bioactive properties. The shortest period to pinhead formation on wheat straw for P. ostreatus, P. eryngii, and P. sajor-caju was 13, 14, and 10 days respectively, which increased by 16, 18, and 19 days on pineapple, orange, and banana peels. Meanwhile, mushroom growth rate was restricted during early substrate colonisation but improved following pinhead formation, resulting in a 28.1, 13.6, and 11.5% increase in yield for P. sajor-caju, P. ostreatus, and P. eryngii on avocado, banana, and pineapple peels, respectively. On the other hand, growing mushrooms using fruit wastes significantly influenced their bioactive functions. This study noted a strong correlation (R=0.8) between total phenolic content, and the antioxidant activity in the studied mushrooms. P. sajor-caju increased its Diphenyl-1- picrylhydrazyl (DPPH) activity by 44% (highest) when cultivated on mango peel, while P. ostreatus and P. eryngii had highest increase of 38.8% and 49.3%, respectively, when grown on avocado peel, with the exception of watermelon rind, which had decreased DPPH activity below that of wheat straw. On the other hand, crude enzyme extract was found to be effective in mushroom hydrolysis. The 1.49 mg/g of glucose measured suggested that the crude enzyme extract was effective in hydrolysing mushroom. Similarly, the yield of galacturonic acid released was related to the rate of peel hydrolysis suggesting that enzyme extracts effectively degraded passion fruit peel. As a result, increased peel hydrolysis, resulted in a higher concentration of odor-active volatiles.