Identification and partial purification of antibacterial compounds against Streptococcus mutans from Galla Rhois / 대한구강보건학회지

OBJECTIVES: This study aims to identify and partially purify antibacterial compounds against Streptococcus mutans from Galla Rhois extract. METHODS: Galla Rhois was extracted with n-hexane or ethanol and concentrated in a rotary evaporator. The antibacterial effect of the Galla Rhois extract against S. mutans was determined by the paper discdiffusion method with n-hexane, ethanol, methanol, ethyl acetate, dimethyl sulfoxide (DMSO), acetone, and distilled water as the solvents. The active compounds were purified by partition chromatography, thin-layer chromatography (TLC), and high-performance liquid chromatography (HPLC). RESULTS: The antibacterial effect of the n-hexane extract was more effective against S. mutans than the ethanol extract (P<0.05). The antibacterial component of Galla Rhois was partially purified using partition chromatography and HPLC, and the antibacterial activity was confirmed. CONCLUSIONS: The partially purified component of Galla Rhois showed strong antibacterial effect against S. mutans. These results confirm that the antibacterial compounds of Galla Rhois can be used for the prevention of dental caries.

Growth inhibition effect of Rubus coreanus Miquel on Candida albicans / 대한구강보건학회지

OBJECTIVES: In this study, the growth inhibition effect of Rubus coreanus Miquel on Candida albicans (C. albicans) was observed. METHODS: The Rubus coreanus Miquel was extracted with 70% methanol and concentrated with a rotary evaporator. Antifungal effect of Rubus coreanus Miquel extract on C. albicans was determined by paper disc diffusion method and standard plate count method. Seven different concentrations (2, 4, 8, 15, 30, 60, 120 mg/ml) of the extract were tested by paper disc diffusion method. Two kinds of concentration (8, 60 mg/ml) of the extract were tested using standard plate count method on C. albicans with different incubating time (for 6, 12, 24 hours immediately after the cultivation). Morphological changes of C. albicans cells after exposure to the extract were observed with scanning electron microscopy (SEM) images. RESULTS: The Rubus coreanus Miquel extract showed an antifungal effect on C. albicans in 8, 15, 30, 60, 120 mg/ml of concentrations (P<0.05). The extract with 8 mg/ml of concentration showed about 30% of growth inhibition at 6 h and with 60 mg/ml it showed about 90% of growth inhibition at 24 h. SEM analysis showed damaged surfaces of C. albicans cells when treated with Rubus coreanus Miquel extract. CONCLUSIONS: The Rubus coreanus Miquel might have the potential as a nobel growth inhibitory agent against C. albicans that causes oral infection.