earticle

영어

The growth-inhibiting activities of persimmon roots-derived materials against intestinal bacteria were evaluatedand compared with that of 1,4-naphthoquinone as a positive control. The active constituent isolated from persimmon roots wascharacterized as 5-hydroxy-2-methyl-1,4-naphthoquinone using various spectroscopic analyses. Treatment with 1,4-naphthoquinone at a dose of 1.0 mg/disc strongly inhibited the growth of 6 intestinal bacteria. Furthermore, when thestructure-activity relationships of 1,4-naphthoquinone’s derivatives were evaluated, 5-hydroxy-2-methyl-1,4-naphthoquinoneand 2-methyl-1,4-naphthoquinone were found to strongly inhibit the growth of Clostridium difficile, Clostridium perfringens,and Escherichia coli without adversely affecting the growth of Bifidobacterium adolescentis, Bifidobacterium longum, andLactobacillus acidophilus. Additionally, 2-hydroxy-1,4-naphthoquinone and 5-hydroxy-1,4-naphthoquinone strongly inhibitedthe growth of C. difficile and C. perfringens, but did not inhibit the growth of E. coli. Taken together, these results indicate thatpersimmon roots-derived materials and some of 1,4-naphthoquinone’s derivatives could be useful preventive agents againstdiseases caused by harmful intestinal bacteria.