Antimicrobial effects of anacardic acids

Abstract

Anacardic acids (6-alkylsalicylic acids) inhibited metabolism of Streptococcus faecalis, Bacillus subtilis, Escherichia coli, Pseudomonas fluorescens, Gyrodinium cohnii, Euglena gracilis and a white mutant of it, Neurospora crassa, Penicillium griseofulvum, Saccharomyces cerevisiae, and Candida utilis. The Gram-positive B. subtilis and S. faecalis were the most sensitive. The sensitivity of Gram-negative bacteria and of the protozoon G. cohnii increased with increasing unsaturation of the alkyl chain in anacardic acids. The latter organism was more sensitive when cultured in medium containing arginine instead of histidine.