两种糖对变异链球菌产酸能力影响的比较研究

目的:通过测量变异链菌代谢高果糖玉米糖浆(high-fructose corn syrup,HFCS)和蔗糖后△pH值的变化,比较两种糖对变异链球菌产酸能力的影响。方法:配制质量浓度为0.25%、0.5%、1%、3%和5%的高果糖玉米糖浆和蔗糖培养基,将变异链球菌UA159于上述各培养基37℃微需氧培养,分别于培养1、4、8、24、48 h各个时间点,用酸度计测量培养前后的pH值,计算ΔpH值,代表变异链球菌的产酸能力。结果:在本研究设定的糖浓度范围和培养时间段内,高果糖玉米糖浆(HFCS)和蔗糖培养基中的ΔpH值均随时间的延长而增大,在培养4～8 h内,HFCS培养基内pH值下降速度快于蔗糖培养基。在培养4、8、24 h时,5种浓度的HFCS培养基中ΔpH值均明显大于蔗糖培养基,差异均有统计学意义(P<0.05),而在培养1 h和48 h时,两种糖培养基中ΔpH值的变化无统计学意义(P>0.05)。结论:在培养4～8 h内,HFCS利于变异链球菌代谢产酸,而在24～48 h内,蔗糖则显示出较强的持续产酸能力。

Effects of high frutose corn syrup or sucrose on acid production capacity of Streptococcus mutans

AIM:To investigate the effect of high frutose corn syrup(HFCS) or sucrose on the acid production capacity of Streptococcus mutans.METHODS:Streptococcus mutans UA159 was cultured in medium containing different concentrations(0.25%,0.5%,1%,3%,5%) of HFCS or sucrose for 48 h under anaerobic condition at 37℃.At different time points(1 h,4 h,8 h,24 h and 48 h),the pH value of the culture medium was measured and ΔpH was calculated.RESULTS:With the increase of culture time,ΔpH values increased in both HFCS and sucrose groups.At 4 h,8 h and 24 h,ΔpH values were significantly higher in HFCS group than in sucrose group(P<0.05).However,no significant difference was observed between the two groups at 1 h and 48 h(P>0.05).CONCLUSION: At early stage of culture,HFCS is more acidogenic than sucrose.However,prolonged culture in sucrose shows sustainable acidogenic effects.