Inhibitory effects of butylated hydroxyanisole on growth of molds and yeasts at different pH conditions and different NaCl concentrations

Abstract

The inhibitory activity of butylated hydroxyanizole (BHA) alone and at different pH (3.5 and 5.5) and different NaCl concentrations (2 and 4%) was screened on 5 molds and 3 yeasts. The conventional tube test was used to determine the minimum inhibitory concentration (MIC). BHA was effective against all of the microorganisms tested in the range of 20 to 320 ?g/mL. The inhibition was pronounced at lowering pH and at NaCl concentrations. BHA was more effective in the presence of NaCl compared to acidic conditions. The MIC values of BHA was significantly lesser in media containing 4% and 2% NaC1 (p< 0.05). Rhizopus arrhizus RAK 220 was the most susceptible fungi to NaCl concentrations. In the presence of 2% NaCl concentration, the MIC value of BHA for Rhizopus arrhizus RAK 220 was reduced to 1/4. The decrease in pH values from 7 to 5.5 and 3.5 had synergistic effect on the inhibitory activity of BHA on some microorganisms (p< 0.05). Among the tests, Geotrichum candidum UUFH 110 was the most susceptible fungi to reduce the pH values, as at pH 5.5 the MIC values of BHA reduced to. and at pH 3.5 reduced to one-sixth. In contrast, at different pH, the MIC values of BHA on Candida albicans CAL 512 not only not decreased but also increased. These studies show that the antifungal properties of BHA can be greatly influenced by environmental factors. é 2015 DAR Publishers. The University of Jordan. All Rights Reserved.