Graphislactone A is an antioxidant produced by Cephalosporium IFB-E001 and M. olivacea. It exhibits dose-dependent scavenging activity against DPPH radicals and metal ion-dependent hydroxyl radicals in vitro. Graphislactone A reduces peroxidation of human LDL and slows peroxidation of linoleic acid by 4.4-fold. It also inhibits acetylcholinesterase (AChE) with an IC50 value of 27 uM.