Analysis Of The Effect Of Erythritol On The Growth,Adhension And Gene Expression Of Streptococcus Mutans In Sucrose

Objective: Sucrose,the largest natural sweeteners and intrinsic sweetness feature,is irreplaceable by any artificial sweetener,so other sugar substitutes and functional sweeteners can be used as sucrose sweetness supplements.The main purpose of this study is to combine sucrose and erythritol,not only using the effect of sucrose natural sweetness and energy,but also the non-cariogenic potential of erythritol,to analysis the effect of erythritol on growth,adhension and gene expression of streptococcus mutans in sucrose,further explore the feasible of erythritol for caries prevention.Methods: 1.In this study,S.mutans was selected as the experimental bacterial strain.S.mutans was cultured respectively in brain heart infusion broth(BHI)including different quantity of erythritol and sucrose.BHI and 4%sucrose as control groups,2%?4%?8%erythritol-4%sucrose as experimental groups,then added S.mutans to those different groups under anaerobic conditions(80%N2,10%H2,10%CO2)at 37?.The optical density(OD)values were measured at 4-h intervals and the growth curves were plotted.At the 24 h,measured the p H of its culture supernatant.2.By using the Scanning Electron Microscope(SEM)and the Confocal Laser Scanning Microscope(CLSM)to observe the adhension effect of S.m on enamel blocks in every group.3.4%Sucrose-BHI as control group,and 3 experimental groups respectively in 2%,4%,8% concentration of erythritol with 4% sucrose,then added S.m bacteria liquid to culture 24 h to get biofilms.Then analysed the related gene expression by RT-PCR.Results 1.Compared with the erythritol and sucrose mixed liquor,the OD of S.mutans in sucrose was higher than those mixed liquor.With the increase of erythritol quantity,the OD and the acid potential were decreased.In the p H experiment,the difference between 4%S and 2%E-4%S was not statistically significant(P?0.05),and difference between each experimental groups and experimental groups with control groups were statistically significant(P?0.05).2.The adherence ratios of S.mutans decreased obviously.The EPS and bacterial population of 4%S,2%E-4%S was more than 4%E-4%S?8%E-4%S by ESEM observing.The total,live and dead bacteria fluorescence intensity of 4%S and 2%E-4%S were not statistically significant(P?0.05).In total and live bacteria difference fluorescence intensity,each experimental groups and experimental groups with control groups were statistically significant(P?0.05).3.The genes in regard to EPS synthesis,adhension,product acid and tolerance acid were affected by the effect of erythritol.About EPS synthesis genes,except 4%E-4%S and 8%E-4%S had not statistically significant on gtf B(P?0.05),others had statistically significant(P?0.05).Spa P,srt A,com D,LDH were showed that 4%E-4%S,8%E-4%S were lower expression than 2%E-4%S and 4%S.Conclusions: Through experiments,it has some inhibitive effect of erythritol on the growth,acid production,adhension and gene expression of Streptococcus mutans in sucrose.It has apparently effect with the increase of erythritol concentration.