Background : Schisandrae Fructus (Omija) has been widely used for medicinal herbs because it is known for its various medical functions and antimicrobial activities. This study was conducted to investigate the antimicrobial activities of extracts from Schisandrae Fructus against six foodborne pathogens (Bacillus cereus, E. coli, Listeria monocytogenes, Salmonella enteritidis, Staphylococcus aureus, Vibrio parahaemolyticus) and figured out the efficient extraction methods.
Methods and Results : Traditionally, Schisandrae Fructus is soaked or boiled in water when people drink it like tea. In this study, we extracted Schisandrae Fructus by soaking in water and ethyl alcohol for 24 hours, ultrasonicating in methyl alcohol and water for 60 minutes, and boiling in water for 30, 60, 90, 120 minutes. Each extract used for paper disc test that estimates antimicrobial activities by measuring the inhibition zone. The blank discs that absorbed with extracts were placed on the agar plates that smeared with each foodborne pathogen, then incubated overnight at 37℃ incubator. Then, antibacterial extracts formed clear zones around the disc. In this study, Vibrio parahaemolyticus was the most sensitive to the all kinds of extracts and methyl alcohol extracts that were obtained by ultrasonicating showed the most strong antimicrobial activities against six foodborne pathogens (23, 12, 29, 18, 23, 28 ㎜). Hot water extracts and soaking extracts in water showed the similar results, and the extracts that was boiled for 60 minutes was the best results (13, 8, 21, 10, 13, 17 ㎜) against all the pathogens.
Conclusion : The extracts from Schisandrae Fructus inhibited the growth of six foodborne pathogens. Soaking and boiling in water are good methods for drinking Schisandrae Fructus like tea because they showed antimicrobial activities in the paper disc test. According to this study, the best boiling time for effective antimicrobial activity is 60 minutes.