Disclosed herein are antimicrobial compositions comprising one or more compound components generally recognized as safe for human consumption, and related methods of use, such compositions and methods as can be employed in a wide range of agricultural, industrial, building, pharmaceutical and/or personal care products and applications. In one embodiment the composition comprises an acid component and a salt of the acid component selected from isobutyric acid, C2 - C5 carbon and methylene homologs thereof, salts of said acid and said homologs, and combinations of said acid, said homologs and said salts； an acid ester component selected from acetic acid, 2-methylpropyl ester and C2 - C5 carbon and methylene homologs thereof； a ketone component selected from 2-butanone and C3 - C5 carbon and methylene homologs thereof and at least two C2 - C5 components isolatable from a volatile by-product of an isolated culture of Muscodor crispans grown on potato dextrose agar, providing said composition is absent naphthalene and azulene derivative compounds.
