没食子酸对植物乳杆菌Lactobacillus plantarum的抑制和促进生长

Gallic Acid Both Inhibits and Promotes the Growth of Lactobacillus plantarum

摘要:

该文以微生物生长曲线、多酚浓度变化和培养液pH值变化为指标，研究了没食子酸（Gallic Acid，GA）和表没食子儿茶素没食子酸酯（Epigallocatechin Gallate，EGCG）对植物乳杆菌CICC 6253生长的影响。结果表明GA和EGCG对植物乳杆菌生长的影响具有浓度依赖性，可表现出抑制和促进的双向调节作用，且二者的作用存在构效差异性。在GA和EGCG分别在5 mg/mL和7 mg/mL以上时，两者都抑制了植物乳杆菌的生长，而当GA和EGCG分别低于4 mg/mL和6 mg/mL时二者都促进了细胞的增殖，且随质量浓度增加其促进作用增大。GA可作为碳 源被植物乳杆菌迅速利用，而EGCG（4 mg/mL）因其良好的细胞亲和性表现出显著的促进作用，高效地促进了植物乳杆菌细胞的增殖，菌落数在28 h内由7.42 lg CFU/mL增加到12.54 lg CFU/mL，与空白对照组相比增加了2个数量级以上。该研究表明，GA和EGCG均表现出对植物乳杆菌的双向调节作用，其中EGCG表现出更佳的益生特性。该文研究结果可为GA和EGCG及类似食源性多酚在益生菌生长调节和相关食品研发中提供参考。

Abstract:

The effects of gallic acid (GA) and epigallocatechin gallate (EGCG) on the growth of Lactobacillus plantarum CICC 6253 were investigated by monitoring the microbial growth curves, concentration changes of the polyphenols, and pH changes of the culture media. GA and EGCG each exhibited two-way regulatory effects on L. plantarum, both inhibiting and promoting the growth of the bacterium in a concentration-dependent manner, and there were differences in structure–activity relationship between the two effects. L. plantarum growth was inhibited at GA and EGCG concentrations above 5 mg/mL and 7 mg/mL, respectively. In contrast, the growth of the bacterium was promoted at GA and EGCG concentrations below 4 mg/mL and 6 mg/mL, respectively, with the effect increasing with increasing concentrations of the polyphenols. GA served as a carbon source that could be rapidly utilized by L. plantarum, whereas EGCG (4 mg/mL) effectively promoted the proliferation of the strain owing to its good cell affinity. The total number of colonies on the EGCG- containing medium increased from 7.16 lg CFU/mL to 12.54 lg CFU/mL in 28 h, which was an increase of more than two orders of magnitude compared with the control group. Both GA and EGCG showed two-way regulatory effects on L. plantarum, but EGCG exhibited superior prebiotic properties. The results of this study can serve as a reference for the use of GA, EGCG, and similar food-derived polyphenols in regulating the growth of probiotics and for the research and development of related foods.