FOOD SCIENCE ›› 2019, Vol. 40 ›› Issue (22): 33-38.doi: 10.7506/spkx1002-6630-20181109-106

• Bioengineering • Previous Articles     Next Articles

Mechanistic Study of the Effect of Ferulic Acid on Tyramine Production by Enterococcus faecalis and Enterococcus faecium

XUE Linlin, WANG Yuan, LI Binbin, WANG Qingling, LU Shiling   

  1. (1. Food College, Shihezi University, Shihezi 832003, China; 2. Xinjiang Academy of Agricultural and Reclamation Science, Shihezi 832000, China)
  • Online:2019-11-25 Published:2019-12-02

Abstract: This study determined the effects of ferulic acid on the growth, gene expression and tyramine accumulation of Enterococcus faecalis XL-M66 and E. faecium XL-M76. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to analyze the expression of tyramine synthesis-related genes in the tyrosine decarboxylation pathway in E. faecalis XL-M66 and E. faecium XL-M76. Additionally, the accumulation of tyramine during 48 h culture was monitored by high performance liquid chromatography (HPLC). Results showed that ferulic acid had little effect on the transcription of the tyrosine decarboxylase (tyrDC) and tyrosine/tyramine permease (tyrP) genes (P > 0.05) in the absence of the substrate tyrosine, but promoted the transcription of the tyrosyl-tRNA synthetase (tyrS) gene (P < 0.05). On the contrary, in the presence of tyrosine, ferulic acid had little effect on the expression of the tyrS gene (P > 0.05), but it could significantly (P < 0.05) inhibit the expression of the tyrDC and tyrP genes. Moreover, ferulic acid significantly (P < 0.05) inhibited the growth of E. faecalis XL-M66 and E. faecium XL-M76 and reduced tyramine production by 27.0% and 19.9%, respectively.

Key words: ferulic acids, Enterococcus faecalis, Enterococcus faecium, tyramine, tyrosine decarboxylase, reverse transcription quantitative polymerase chain reaction

CLC Number: