ABSTRACT
Objective:To study the effects of 3 extracts from Chinese gall on the growth and metabolism of 6 kinds of oral bacteria.Methods:Through a series of extraction and purification,3 active monomer,gallnut extract gallic acid,methyl gallate and gallic acid ethyl ester were selected.Streptococcus mutansUA159(UA159),Actinomyces viscosus (Av),Porphyromonas gingivalis (Pg),Enterococcus faecalis (Ef),Fusobacterium nucleatum(Fn) and Candida albicans (Ca) were treated by the extracts respectively,The growth and metabolism of the becteria were studied by liguid dilution method.Results:The MIC(mg/ml) of Gallic acid anainst the bacteria was 2.5-5,methyl gallate 2.0-4.0 and gallic acid ethyl ester 1.25-2.5.The extracts at 1 mg/ml could inhibit the growth,acid production and extracellular polysaccharides of the 6 oral pathogens.And ethyl gallate showed the strongest effects.Conclusion:Gallic acid and methyl gallate and ethyl gallate at low concentration may inhibit the growth,acid metabolism and glucose metabolism of oral bacteria.