Comparison of the antioxidant activity and nutritional contents of ectomycorrhizal mushroom extracts in Korea

The extracts of four species of ectomycorrhizal mushrooms—Cantharellus cinnabarinus (OK1247), Lactarius parallelus (OK1264), Tricholoma matsutake (OK1282), and Ramaria botrytis (OK1283)—were prepared to determine their antioxidant activities and nutritional properties. R. botrytis extract displayed the highest 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (33.8%), ferric reducing antioxidant power (0.38), reducing power (0.35), total polyphenol (13.83 mg gallic acid equivalent/g), and flavonoid contents (2.56 mg quercetin equivalent/g). L. parallelus extract displayed the highest nitrite scavenging activity. Analysis of amino acid contents revealed that C. cinnabarinus extract had the highest total amino acid (1,046.1 mg/kg) and essential amino acid (404.9 mg/kg) contents, while R. botrytis extract had the lowest total amino acid (708.3 mg/kg) and essential amino acid (247.3 mg/kg) contents. Among the amino acid components detected in the four ectomycorrhizal mushrooms, cysteine was the most abundant, accounting for 14.3~20.7%, followed by phenylalanine, which accounted for 9.5 ~13.4% of all amino acids. In summary, the antioxidant activities were the highest in R. botrytis extract, and the amino acid content was the highest in C. cinnabarinus extract, among the four ectomycorrhizal mushrooms.