title: [Effect of Lactobacillus acidophilus on metabolizing lactic acid in formula milk: a quantitative analysis of the effect of erythritol].
abstract: OBJECTIVE
  To evaluate the lactic acid productivity of Lactobacillus acidophilus (La) exposed to formula milk containing different concentration of erythritol.
  
  
  METHODS
  La was cultured under anaerobic condition (80% N(2), 10% CO(2), 10% H(2)) at 37 °C in five experimental groups (formula milk mixed with different concentrations of erythritol). The five experimental groups contained 1%, 2%, 4%, 6%, and 8% erythritol, respectively (groups 1% E-M, 2% E-M, 4% E-M, 6% E-M, 8% E-M). Formula milk served as control group (group M). The lactic acid was analyzed by high performance liquid chromatography (HPLC) at 4 h intervals during 24 h. The peak-area of lactic acid was recorded and used to calculate the concentration of lactic acid through the equation of a standard curve (y = 590 244x + 67 507). ANOVA and Tukey HDS analysis were used to analyze the data.
  
  
  RESULTS
  The concentration of lactic acid at 24 h was group M [(4.693 ± 0.105) g/L], group 1% E-M[(4.114 ± 0.186) g/L], group 2% E-M[(3.720 ± 0.158) g/L], group 4% E-M[(3.045 ± 0.152) g/L], group 6% E-M[(2.971 ± 0.086) g/L], group 8% E-M[(2.789 ± 0.142) g/L]. Statistically significant differences in lactic acid concentrations were found between different time points (P < 0.05) and between different groups (F = 187.448, P < 0.05). Moreover, the concentrations of lactic acid in each experimental group was lower than that in control group (P < 0.05). The difference among groups 4% E-M, 6% E-M, and 8% E-M were not statistically significant (P > 0.05).
  
  
  CONCLUSIONS
  Erythritol showed the inhibition potential against La in metabolizing lactic acid in formula milk. The effect of erythritol was concentration depended. The higher concentration of erythritol contained in the milk, the better the inhibition potential against La in metabolizing lactic acid.
authors.affiliation: Department of Pedodontology, Hospital of Dentistry, Fujian Medical University, Fuzhou 350002, China; Email: dentyao@163.com.
authors.forename: Jun
authors.initials: J
authors.lastname: Yao
authors.affiliation: Department of Pedodontology, Hospital of Dentistry, Fujian Medical University, Fuzhou 350002, China.
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Pedodontology, Hospital of Dentistry, Fujian Medical University, Fuzhou 350002, China.
authors.forename: Jiali
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Pedodontology, Hospital of Dentistry, Fujian Medical University, Fuzhou 350002, China.
authors.forename: Xiujuan
authors.initials: X
authors.lastname: Yang
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004305:Dose-Response Relationship, Drug; D004896:Erythritol / Q000494:pharmacology*; D006801:Humans; D007223:Infant; D041943:Infant Formula / Q000737:chemistry / Q000378:metabolism* / Q000382:microbiology; D019344:Lactic Acid / Q000032:analysis / Q000378:metabolism*; D007779:Lactobacillus acidophilus / Q000187:drug effects* / Q000378:metabolism; D008892:Milk / Q000737:chemistry / Q000378:metabolism* / Q000382:microbiology; D013997:Time Factors
chemical_list: D019344:Lactic Acid; D004896:Erythritol