Wild mushrooms in Nepal: Some potential candidates as antioxidant and ACE-inhibition sources

Twenty-nine mushrooms collected in the mountainous areas of Nepal were analyzed for antioxidant activity by different methods, including Folin-Ciocalteu, ORAC, ABTS, and DPPH assays. Intracellular H₂O ₂-scavenging activity was also performed on HaCaT cells. The results showed that phenolic compounds are the main antioxidant of the mushrooms. Among studied samples, Inonotus andersonii, and Phellinus gilvus exhibited very high antioxidant activity with the phenolic contents up to 310.8 and 258.7 mg GAE/g extracts, respectively. The H₂O₂-scavenging assay on cells also revealed the potential of these mushrooms in the prevention of oxidative stress. In term of ACE-inhibition, results showed that Phlebia tremellosa would be a novel and promising candidate for antihypertensive studies. This mushroom exhibited even higher in vitro ACE-inhibition activity than Ganoderma lingzhi, with the IC₅₀ values of the two mushrooms being 32 g/mL and 2 g/mL, respectively. This is the first time biological activities of mushrooms collected in Nepal were reported. Information from this study should be a valuable reference for future studies on antioxidant and ACE-inhibitory activities of mushrooms.