Pleurotus ostreatus, a Culinary Mushroom as a Functional Food to Treat Inflammatory Conditions

Abstract

Pleurotus ostreatus is a culinary-medicinal mushroom which is grown worldwide commonly known as American oyster. Various properties of P. ostreatus have been reported in literature such as antinociceptive, hypocholesterolaemic, antioxidant and antitumour effects. Our previous studies have reported the chronic hypoglycaemic effect of Pleurotus.1 The anti-inflammatory potential of suspensions of freeze dried and powdered (SFDP) P. ostreatus in normal and alloxan- induced diabetic Wistar rats was investigated using the carrageenan-induced rat paw oedema model. The potency of P. ostreatus was compared with indomethacin. The SFDP P. ostreatus at doses of 125, 250, 500, 750 and 1000 mg/kg were orally administered to healthy Wistar rats. The mushroom showed significant (p < 0.05) reduction of paw oedema at doses of 250 - 1000 mg/kg which was comparable to that of indomethacin. Maximum inhibitory activity was demonstrated at the dose of 750 mg/kg (92 % inhibition). The SFDP P. ostreatus at doses of 500 and 1000 mg/kg showed long lasting activity at both early and late phases of carrageenan-induced rat paw oedema in diabetic rats. Hence, the mushroom exerted protective effects on the inflammatory pathologies in rats with diabetes. The possible mechanisms by which P. ostreatus mediates the anti-inflammatory activity were antihistamine activity, inhibition of cell migration to the site of inflammation, membrane stabilizing activity and inhibition of nitric oxide production. Promising anti-inflammatory activity of P. ostreatus warrants its application as a functional food during inflammatory conditions. This mushroom will be beneficial as a source of anti-infiammatory agents in the pharmaceutical industry.