The antibiotic activity and mechanisms of sugarcane (Saccharum officinarum L.) bagasse extract against food-borne pathogens
Yi Zhao, Mingshun Chen, Zhengang Zhao, Shujuan Yu
College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510640, PR China.
Sugarcane bagasse contains natural compositions that can significantly inhibit food-borne pathogens growth. In the present study, the phenolic content in sugarcane bagasse was detected as higher than 4 mg/g dry bagasse, with 470 mg quercetin/g polyphenol. The sugarcane bagasse extract showed bacteriostatic activity against the growth of Staphylococcus aureus, Listeria monocytogenes, Escherichia coli and Salomonella typhimurium. Additionally, the sugarcane bagasse extract can increase the electric conductivity of bacterial cell suspensions causing cellular leaking of electrolytes. Results of sodium dodecyl sulfate polyacrylamide gel electrophoresis suggested the antibacterial mechanism was probably due to the damaged cellular proteins by sugarcane bagasse extract. The results of scanning electron microscopy and transmission electron microscopy showed that the sugarcane bagasse extract might change cell morphology and internal structure.
Keywords: Sugarcane bagasse; Food-borne pathogens; Polyphenols; Phenolic acid; Bacteriostatic activity.