Different extraction methodologies and their influence on the bioactivity of the wild edible mushroom Laetiporus sulphureus (Bull.) Murrill†
Laetiporus sulphureus is an edible wood-rooting basidiomycete. The nutritional and medicinal properties of this mushroom have long been known by traditional practitioners. The aim of this study was to determine the proximate composition, total phenol antioxidant capacity and antimicrobial activities of different extracts of L. sulphureus. Different extraction methodologies, including high energy techniques, were employed and their effect was examined on the activity of the extracts. Optimum extraction methodologies (classical and ultrasound-assisted) provided one fraction containing neutral and polar lipids and the other fraction containing fungal carotenoids and pigments. Fatty acid analysis indicated a predominant level of polyunsaturated fatty acids followed by saturated and mono-unsaturated fatty acids. Both the aqueous methanolic and water extracts contained higher TPC and showed better antioxidant capacity than the ethanolic extract. Irrespective of the type of extraction applied, L. sulphureus showed good antimicrobial activity against all the tested bacteria and fungi, being in some cases stronger than the used antibiotics and mycotics. Therefore, this edible mushroom could be considered as a positive candidate to be utilised by the food industry, not only for obtaining bioactive compounds to be used as natural antioxidants/antimicrobial agents, but possibly also for its nutritional value and health benefits.