The Effect of Supplementing Mushroom Growing Substrates on the Bioactive Compounds, Antimicrobial Activity, and Antioxidant Activity of Pleurotus ostreatus

Abstract

Pleurotus ostreatus mushroom contains important bioactive compounds and has several biological activities; however, mushroom growing substrates have major influence on chemical and functional characteristics of the mushroom. Hence, the study aimed to evaluate the influence of supplementing mushroom growing substrates with wheat bran (WB) towards yield/productivity, bioactive compounds, and antimicrobial and antioxidant activity of P. ostreatus. The mushroom was cultivated on sugarcane substrates supplemented with increasing levels of WB (0%–20%). The mushroom extracts were screened for bioactive compounds using gas chromatography-mass spectrometry (GC-MS). Antimicrobial activity was carried out using microplate assay, while antioxidant potential was investigated using reducing power assay. The addition of supplements on mushroom growing substrates had an influence on mushroom yield; hence, higher supplementation (18% and 20%) produced higher yield. The GC-MS revealed several bioactive compounds with known activity, such as vitamin E, phenol, fatty acids, and terpenoids. Concentration-dependent antioxidant activity was observed; hence, extracts at higher concentrations gave significantly higher reducing power. The P. ostreatus extract had antimicrobial activity against all the tested organisms, with S. aureus showing high susceptibility to most of the extracts. However, mushrooms grown on bagasse substrates supplemented with 14% (0.02 mg/ml) and 20% WB (0.08 mg/ml) proved to have better antimicrobial activity on Escherichia coli. The difference in susceptibility demonstrates that substrates type and composition could have an influence on bioactive compounds found within mushrooms, also influencing medicinal properties of edible mushroom. Thus, supplementing mushroom growing substrates not only improve yield, but also can contribute to bioactive compounds with medicinal potential.

Metabolite Profiling of Pleurotus ostreatus Grown on Sisal Agro‐Industrial Waste Supplemented with Cocoa Almond Tegument and Wheat Bran

“…Nevertheless, little in known regarding the chemical composition of secondary bioactive compounds produced by Pleurotus species growing in different substrates. The chemical profile of Pleurotus ostreatus grown on sugar cane tops and sugar cane bagasse with wheat bran supplements was assessed by gas chromatography‐mass spectrometry (GC/MS) and it revealed differences that reflected on the antioxidant and antimicrobial activity of the extracts [36] . Altogether, identifying these compounds highlights the potential of P. ostreatus as a promising source of bioactive compounds with industrial and nutraceutical relevance.…”

Olive mill solid waste induces beneficial mushroom-specialized metabolite diversity: a computational metabolomics study

“…As a matter of fact, the olive oil industry produces extensive amounts of highly polluting by-products, both water waste and solid waste. Olive oil extraction can generate up to 30-40% OMSW and much effort has been invested in its exploitation 20,21 .Here, it is important to note that the type or characteristics of the growing substrate significantly influence the content of certain bioactive compounds in the mushrooms 22,23 . For example, recent studies have exhibited an increase in the healthy and beneficial glucans alpha and beta concentrations in correlation with the addition of several concentrations of olive mill waste to the substrate 24 .…”