ANTI-MICROBIAL ACTIVITY OF AROMA CHEMICALS AND ESSENTIAL OILS

Determination of the minimum inhibitory concentrations (MIC) of 212 common soap fragrance raw materials demonstrated that the paper disc-petri plate technique does not reflect the relative antimicrobial activity of these materials. Commonly used soap bacteriostats were 100-1000 times more effective than the most active fragrance materials. Of 521 fragrance materials initially screened by the petri plate method, 44% were inhibitory against 1 of the 3 test organisms, and 15% were effective against all 3 (Staphylococcus aureus, Escherichia coli, Candida albicans). Of a selected number (212) of these positive materials, subsequently screened against a lipophilic diphtheroid organism (Corynebacterium sp.), 64 materials (30%) were positive against all 4 test organisms. Only 9 materials (4%) had a MIC as low as 50 ppm compared to the common soap bacteriostat TCC [3,4,4''-trichlorocarbanilide], [human] hand-degerming tests, no reduction of bacterial counts was obtained with a soap containing the most active fragrance materials. Creation of a practical ant-microbial soap fragrance does not appear possible.