In vitro study of antigrowth capacity and antiacid capacity on Sreptococcus sobrinus 6715 of sorghum procyanidin dimers.

The bacteria grow in oral cavity and product acids, which could induce dental caries. In this study, in order to obtain the relationship between procyanidin dimers from sorghum episperm (sorghum procyanidins, SPC) and its anticaries effect. The extract of SPC purified by macroporous resin was divided into three parts by gel chromatography, marked as GPC-1, GPC-2, and GPC-3 in order. The ESI-MS and MS/MS analysis indicated that the main composition of GPC-2 was procyanidin dimers. In addition, the capacities of antigrowth and antiacid on Sreptococcus sobrinus 6715 were analysised to investigate the effect of SPC dimers in protecting against dental caries. The results indicated that the minimum inhibitory concentration (MIC) of SPC dimers was 16 mg/mL. Furthermore, the SPC dimers had notable preventive effect < against the acid production of Sreptococcus sobrinus 6715 compared with the control group, which suppressed in a dose-dependent manner by pH decline. These findings indicated that SPC dimers had potential to be used as anticaries preventive medicine due to its strong capacity of antigrowth and antiacid.