Antioxidant and Antimicrobial Influence on Oyster Mushrooms ( Pleurotus ostreatus ) from Substrate Supplementation of Calcium Silicate

Supplementation of the substrate of mushrooms with calcium silicate and other minerals is usually used as a preventive measure against pests and other contaminants during the production of oyster mushrooms. Little is known of the effects of this supplementation on the quality of the mushrooms produced. In the work described herein, the supplementation of oyster mushrooms was performed with 5 supplementation levels (0%, 0.5%, 1%, 2% and 4%) on mushrooms from two different locations in Brazil, the two flushes of mushrooms produced were analysed in terms of phenolic compounds, organic acids, and the antioxidant, antibacterial and antifungal activities, and finally the data was subjected to a linear discriminant analysis to understand the discrimination of the supplementation percentages. Overall, intermediate supplementation until 1% seemed to have a positive effect on the mushrooms from Mogi-das-Cruzes region, while high supplementation favoured the mushrooms from the region of Presidente Prudente. Supplementation showed positive effects on the mushrooms by increasing the production of some secondary metabolites while not showing any negative cytotoxic effects.