The Antimicrobial Activity of Sweet Cherry (Prunus avium) Extracts: II. Measurement of Sensitivity and Attenuation of Gram-Positive and Gram- Negative Bacteria and C. albicans in Culture

We have previously measured the antimicrobial activities of sweet cherry extracts (SCE) in grampositive/ negative bacteria and C. albicans using disk diffusion method [1]. Extracts were subdivided into the following categories: Whole juice (WJE), methanol-extracted (MEJ), ddH2O-extracted pomace (dPOM) and methanol-extracted pomace (mPOM). In this study the minimum inhibitory concentrations (MICs) were assessed @ 24 hrs. following bacterial/ fungus inoculations. WJE: MICs (1/4 – 1/8) for gram-positive and (undiluted – 1/32) for gram-negative bacteria; MIC for fungus was 1/32. MEJ: MICs (undiluted – 1/16) for gram-positive and (undiluted – 1/16) for gram-negative bacteria; MIC for fungus was 1/16. dPOM: MICs (undiluted – 1/32) for gram-positive and (undiluted – 1/32) for gram-negative bacteria; MIC for fungus was 1/2. mPOM: MICs (1/2 – 1/16) for gram-positive and (1/2 – 1/16) for gram-negative bacteria; MIC for fungus was 1/8. These results confirm the measurable attenuating effect of P. avium extracts on the differential resistance/sensitivity of gram-positive and gram-negative bacteria and C. albicans in broth cultures.