A method of inhibiting microbial growth and of inhibiting oxidation of a target organic compound or food, medicine, or cosmetic is disclosed. The method comprises contacting the target organic compound or food with an effective amount of a phenolic compound comprising a single 6-carbon ring and from four to six hydroxyl groups, wherein an effective amount of the phenolic compound is an amount sufficient to inhibit oxidation of the target organic compound or food by at least 50% and sufficient to inhibit microbial growth in the presence of the target organic compound or food by at least 50%. The phenolic compound comprising a single 6-carbon ring and from four to six hydroxyl groups is preferably 1,2,3,4-tetrahydroxybenzene.