Comparison of Bioactivities of Water Extracts from Five Edible Mushrooms

In order to provide a theoretical basis for the development and utilization of edible mushrooms, the antioxidant, immunomodulatory and anti-radiation activities of water extracts from five edible mushrooms, including Volvariella volvacea, Grifola frondosa, Russula vinosa Lindblad, Coprinus comatus and Ganoderma applanatum were studied and compared with each other.

The contents of total sugar, crude polysaccharide, total protein, total phenols and total flavonoids in water extracts from the five edible mushrooms were determined by the phenol-sulfuric acid method, the Coomassie brilliant blue method, the Folin-Ciocalteu method and the aluminium chloride method, respectively. Their in vitro antioxidant activities were evaluated by 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radical, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, and hydroxyl radical scavenging and total reducing power assays. Their proliferative activities on macrophage RAW264.7 cells were detected by cell counting kit-8 (CCK-8) method. Their protective effects against ⁶⁰Co γ irradiation-induced damage in mouse hepatocytes AML-12 were investigated in vitro.

Total sugar was the most abundant constituent in water extracts from Volvariella volvacea, Grifola frondosa, Russula vinosa Lindblad, Coprinus comatus and Ganoderma applanatum, accounting for (80.90±1.20)%, (67.00±2.48)%, (55.31±0.55)%, (84.87±7.31)% and (58.19±1.50)% of the extracts, respectively. The crude polysaccharide content of water extract from Grifola frondosa was the highest, (61.28±2.95)%. All the water extracts had good antioxidant activities, of which the water extract of Ganoderma applanatum had the best antioxidant activity. In addition, the water extracts at different concentrations (10–200 μg/mL) promoted the proliferation of RAW264.7 macrophages, and the effect of the water extract of Ganoderma applanatum at low concentrations was more significant. The decreased survival rate of AML-12 cells induced by ⁶⁰Coγ radiation could be significantly improved by the water extract of Volvariella volvacea in the concentration range of 10–200 μg/mL. The water extract of Ganoderma applanatum had a significant protective effect against radiation-induced cell damage at low concentrations.

The water extracts from the five edible mushrooms have different biological activities. Overall, the water extract from Ganoderma applanatum shows better antioxidant activity, immunomodulatory effect and anti-radiation activity, so it is worthy of further study.