大蒜精油对屎肠球菌和粪肠球菌产苯乙胺和酪胺的影响

Effect of Garlic Essential Oil on the Production of Phenylethylamine and Tyramine by Enterococcus faecium and Enterococcus faecalis

本试验采用双倍试管稀释法,测定大蒜精油分别对高产苯乙胺和酪胺的E.faecium和E.faecalis的最低抑菌浓度(MIC)和最低杀菌浓度(MBC);并利用高效液相色谱法测定不同浓度的大蒜精油对两株高产苯乙胺和酪胺菌株的影响,从而明确大蒜精油对其产生物胺能力的抑制作用。结果表明:大蒜精油对供试菌株都具有较强的抑菌活性,大蒜精油对E.faecium的最大抑制率可达48.20%,对E.faecalis的最大抑制率为52.41%,且抑菌效果随大蒜精油浓度的增大而逐渐增强;在大蒜精油的添加量为1/2 MIC时,大蒜精油对E.faecium和E.faecalis的生长具有抑制作用;当大蒜精油浓度为0.025%时,能够显著(p<0.05)降低供试菌株产苯乙胺和酪胺的含量,苯乙胺含量与空白组相比降低了26.61%,酪胺的降低了15.54%。说明大蒜精油对高产酪胺和苯乙胺的菌株具有显著(p<0.05)抑制效果,从而减少了酪胺和苯乙胺的生成。

The minimum inhibitory concentration（MIC） and minimum bactericidal concentration（MBC） of garlic essential oil against two phenylethylamine-and tyramine-producing bacteria-Enterococcus faecalis and Enterococcus faecium-were measured in vitro using the double tube dilution method. The effects of a variety of concentrations of garlic essential oil on the two strains with high phenylethylamine-and tyramine-production were measured by high performance liquid chromatography（HPLC）, to determine the inhibitory effect of garlic essential oil on biogenic amine production by the two strains. The results showed that garlic essential oil displayed sstrong antimicrobial activity against E. faecalis and E. faecium, and the corresponding maximum inhibitory rates（IRs） reached 52.41% and 48.20%, respectively. The antimicrobial effect increased as the concentration increased. When the amount of added garlic essential oil was ？ MIC, it showed an inhibitory effect on the growth of E. faecalis and E. faecium. At a concentration of 0.025%, the garlic essential oil could significantly reduce the production of phenethylamine and tyramine by the test strains; the production of phenylethylamine and tyramine was reduced by 26.61% and 15.54%, respectively, from of the control. The result indicated that garlic essential oil exhibited a significant inhibitory effect on E. faecalis and E. faecium, thereby reducing the production of phenethylamine and tyramine.