Abstract:The antimicrobial activity,minimum inhibitory concentration(MIC) and minimum bactericidal concentration(MBC) of essential oil in Mentha piperita and Mentha cardiaca were determined in this study.Furthermore,the polyphenol content and antioxidant activity of solid residues in two mints were also investigated.The results demonstrated that the two essential oils exhibited inhibition effect on E.coli,Staphylococcus aureus,Salmonella typhimurium and Listeria monocytogenes,however,without inhibitory effect was observed in the case of Salmonella enteritidis and Aspergillus niger.The antimicrobial ability of peppermint essential oil was stronger than Scotch spearmint essential oils.Besides,the polyphenol content in residues of peppermint was significantly decreased,but that in Scotch spearmint had no significant reduction.The residues of two mints had stronger ability of scavenging DPPH after water distillation,but the antioxidant ability in FRAP assay reduced significantly.
