Total phenolic flavonoids contents and antioxidant of Lentinus polychrous Lev. a local cultivated mushroom in Nakhon Phanom Province

Abstract

Lentinus polychrous Lev. is an edible wild mushroom found in the northeastern region of Thailand, and surveys have reported its presence in the Lao People's Democratic Republic. L. polychrous has distinctive characteristics and a good taste, making it popular for culinary use. Fruiting bodies and mycelium of L. polychrous have been reported to possess bioactivities such as antioxidant, anti-cancer, antiviral, anti-inflammatory and immunomodulating properties. A group of mushroom growers in Nakhon Phanom province operates mushroom production in mushroom houses and sells their products in local markets, generating income throughout the year. In this study, the total phenolic and flavonoid contents of local cultivated mushroom extracts, locally found in Nakhon Phanom province, were analyzed. Extractions were carried out using water at different temperatures (RT, 60 and 80 °C) and 75% ethanol, separately for the mushroom stalks and caps. The results showed that the extracts from both of stalks and the caps of the hardy mushroom contained significantly different contents of total phenolic and flavonoid contents per gram of dried mushroom (p < 0.05). The extracts obtained using water at different temperatures from both mushroom caps and stalks yielded higher amounts of crude extract compared to those obtained using ethanol. The crude extract yields ranged from 57.53 to 254.80 mg per gram of dry weight with total phenolic content ranging from 43.34 mg GAE/g crude to 145.29 mg GAE/g crude. L. polychrous extract obtained from the mushroom cap using water at room temperature yielded a significantly higher total phenolic content per gram of crude extract compared to the other extraction methods. The flavonoid content in the mushroom ranged from 58.37 mg QE/g crude extract to 379.08 mg QE/g crude extract. The extract obtained from the mushroom stalks using water at room temperature yielded a significantly higher flavonoid content per gram of crude extract compared to the other extraction methods. Antioxidant activity showed that the extracts of both stalk and cap extracted with ethanol and water at different temperatures had significantly higher IC₅₀ values than standard antioxidants (p < 0.05). The analysis of total phenolic flavonoid contents and antioxidant activity in L. polychrous extracts provides fundamental data valuable for enhancing the production process and improving the quality of local mushrooms in Nakhon Phanom province. Additionally, it serves as a foundation for further investigation into other bioactive properties to support the development of health-related products or functional foods from L. pochrous.