The research was undertaken to determine the bacteriostatic effects of the concentrate of Japanese apricot juice (bainiku-ekisu), which is a popular health food in Taiwan and Japan, on Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923, and Escherichia coli ATCC 25922. The results show that E. faecalis, S. aureus, and E. coli could be killed or inhibited by bainiku-ekisu at concentrations between 1.0 and 10.0？mg/mL. The minimum inhibitory concentration (MIC) was 1？mg/mL for all strains, and the minimum bactericidal concentrations (MBCs) were 5, 2.5, and 2.5？mg/mL for E. faecalis, S. aureus, and E. coli, respectively. Using the growth rate to calculate the MICs and MBCs, the MICs were 1.55, 1.43, and 0.97？mg/mL, and the MBCs were 2.59, 2.63, and 2.25？mg/mL for E. faecalis, S. aureus, and E. coli, respectively. According to the D values, E. faecalis and S. aureus exhibited lower resistance than E. coli at lower bainiku-ekisu concentrations (1.0 and 2.5？mg/mL), and the resistance of these two pathogens was better than that of E. coli at higher bainiku-ekisu concentrations (5.0 and 10.0？mg/mL). The Z values of the E. faecalis, S. aureus, and E. coli strains were 3.47, 4.93, and 11.62？mg/mL, respectively. 1. Introduction Enterococcus faecalis, Staphylococcus aureus, and Escherichia coli have been recognized as important pathogens that cause human disease and regularly infect hospitalized patients. S. aureus and E. coli are also common causes of food poisoning. Antibiotics are the major tools to treat bacterial infections and cure patients. However, bacteria are highly adaptable and can develop resistance to antibiotics, yielding resistant pathogens such as methicillin-resistant S. aureus (MRSA) [1]. These antibiotic-resistant bacteria pose significant dangers to hospitalized patients because infections with resistant bacteria are difficult to treat with antibiotics. Therefore, it is important to reduce antibiotic consumption to eliminate the development of antibiotic-resistant bacteria. In clinical settings, antibacterial effects are usually quantified as the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) [2]. These methods are easy ways to determine the curative antibiotic dose; however, the dose range is wide. The use of more antibiotics might produce antibiotic-resistant bacteria. The decimal reduction time (D value) and the resistance coefficient (Z value) are widely used in thermal death time (TDT) data analysis to determine the heat resistance of the bacteria [3]. The difference between the D and
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