Antioxidant activity and phenolic content of brick caps mycelium (Naematoloma sublateritium) extracts

A total of 5 subfractions were obtained from methanol extracts of N. sublateritium mycelia via systemic extraction using n-hexane, chloroform, ethyl acetate, n-butanol, and water. The trolox equivalent antioxidant capacity of the chloroform subfraction was 649.40 μmol/g of sample. The highest ferric reducing/antioxidant power (FRAP) assay value was found in the chloroform subfraction (299.24 μmol of FeSO4·7H2O/g). The chloroform and ethyl acetate subfractions exhibited the highest total phenolic compound contents, with ferulic acid equivalents of 31.66 and 48.57 mg/g, respectively. The phenolic acids in the subfractions were further identified using liquid chromatography-tandem mass spectrometry. The 5 phenolic acids of 4-hydroxybenzoic acid, α-resorcylic acid, 4-coumaric acid, salicylic acid, and gentisic acid were found to be the major phenolics in the mushroom.