(S)-雌马酚对肠道菌群的体外调控作用及其可代谢性研究

Interaction between(S)-equol and human gut microbiota in vitro

【目的】研究(S)-雌马酚对人体肠道菌群的体外调控作用和人体肠道菌群对(S)-雌马酚的代谢衍生作用。【方法】采用人体肠道菌群体外批量发酵、细菌16S rRNA基因高通量测序、气相色谱、液相色谱和质谱等检测(S)-雌马酚与人体肠道菌群体外相互作用。【结果】体外添加(S)-雌马酚对总体人肠道菌群结构和短链脂肪酸产量影响不明显。添加0.45mmol/L(S)-雌马酚组与对照组相比,未检测到相对丰度发生显著变化的细菌;添加0.90mmol/L(S)-雌马酚组与对照组相比,显著增加了肠杆菌科(Enterobacteriaceae)等条件致病菌的相对丰度,减少了潜在益生菌粪球菌属(Coprococcus)的比例。代谢分析发现,发酵培养液中(S)-雌马酚的浓度降低了约15%-30%,推测可能被微生物进一步降解或衍生修饰。【结论】从体外调控肠道菌群的角度判断,0.45 mmol/L(S)-雌马酚相对较安全,而0.90 mmol/L(S)-雌马酚可能会破坏肠道菌群平衡。(S)-雌马酚可以被人体肠道菌群进一步代谢,其特定代谢产物的结构与功能及其体内生物安全性有待进一步研究。

[Objective] To study the regulatory effect of(S)-equol on human gut microbiota and the metabolic effect of human gut microbiota on(S)-equol. [Methods] The interaction between(S)-equol and human gut microbiota was detected by batch fermentation in vitro, bacterial 16S rRNA gene high-throughput sequencing, gas chromatography, high performance liquid chromatography(HPLC),and mass spectrometry. [Results](S)-equol had no significant effect on the overall structure of human gut microbiota or the concentrations of short chain fatty acids(SCFAs). No significant change in the relative abundance of bacteria was detected between the 0.45 mmol/L(S)-equol group and the control group. However, 0.90 mmol/L(S)-equol significantly increased the relative abundance of conditional pathogens such as Enterobacteriaceae and reduced that of potential probiotics Coprococcus. The concentration of(S)-equol in the fermentation broth decreased by 15%–30%, which suggested that(S)-equol may be degraded or modified by gut microbiota. [Conclusion] From the perspective of regulating gut microbiota in vitro, 0.45 mmol/L(S)-equol is safe, while 0.90 mmol/L(S)-equol may disturb the balance of gut microbiota.(S)-equol can be further metabolized by human gut microbiota,and the structure and function of the specific metabolites and the biological safety of(S)-equol in vivo remain to be studied.