RESUMEN
The mycelial biomass production of four strains (WS218-1, WS218-2, CST01, and CST02) of Pleurotuscystidiosus in liquid culture using coconut water as a medium was evaluated. Mycelia were extracted and the1,1-diphenyl-2-picrylhydrazyl radical scavenging activities and total phenolic contents were analyzed. Themycochemicals of the best strain were also screened using a thin-layer chromatography spot test. Resultsrevealed that WS218-2 strain produced the heaviest mycelial biomass (6.57 g fresh wt. and 0.39 g dry wt.)while CSC02 and WS218-1 strains registered the lowest fresh and dry weight, respectively. Ethanolic extractof the WS218-2 strain showed the highest radical scavenging activity (79.01%) and contained the highestphenolic content (95.67 mg gallic acid equivalents/g of sample). Eleven mycochemicals including essential oil,triterpenes, anthraquinones, tannins, flavonoids, phenols, fatty acids, alkaloids, steroids, sugars, and coumarinswere detected in WS218-2 mycelia. Pleurotus cystidiosus mycelia could be a valuable source of naturalantioxidants and bioactive metabolites and it is strain-dependent.