Comparison study on antioxidant, DNA damage protective and antibacterial activities of eugenol and isoeugenol against several foodborne pathogens

Eugenol and its isomer isoeugenol are both used as flavouring agents or food additives in food products, and have both some similar biological properties. However, the difference in biological activities between eugenol and isoeugenol is rarely studied. In this study, the profiles of antioxidant, DNA-protective effects and antibacterial activities of eugenol and isoeugenol against several common foodborne pathogens were investigated and compared under various experiment conditions. Results showed that eugenol and isoeugenol had strong antioxidant activity, the protective effect against DNA damage and antibacterial activity. In addition, it was found that isoeugenol exhibited the higher biological activities mentioned above than eugenol, which was because isoeugenol had a carbon–carbon double bond closer to the benzene ring compared with eugenol. However, the specific reason needs to be further studied.