Evaluation of different kinds of organic acids and their antibacterial activity in Japanese Apricot fruits

The fruit of Japanese apricot is rich in organic acids, which have strong antibacterial activities. The types and contents of organic acids in six different cultivars of Japanese apricot fruit were evaluated by reverse-phase high performance liquid chromatography (HPLC). The antibacterial activity against Escherichia coli, Bacillus subtilis and Streptococcus suis was also determined. The results revealed that there are nine types of organic acids in the presence of the extracts of Japanese apricot fruit, including oxalic, tartaric, malic, ascorbic, acetic, citric, maleic, fumaric and succinic acids. The total organic acid content of ‘Zhonghong’ was the highest among the studied cultivars, and the main organic acids present were citric and malic acids. The antibacterial activity on the growth of E. coli and B. subtilis was higher than on the growth of S. suis. The antibacterial effect of acetic acid against bacteria was the best, and the minimum antibacterial concentration (MIC) against E. coliand B. subtilis was 0.417 mg/mL. The citric and maleic acids were also against these three strains of bacteria. The results suggest that the antibacterial activity is related to the organic acid composition and content of Japanese apricot fruit.