Antibacterial mechanism and performance of PLA/TP composed nanofiber membrane

Polylactic acid(PLA) solution mixed with tea polyphenol(TP) was electrospun into PLA/TP composed nanofiber membrane whose composition,antibacterial performance and mechanism were investigated using infrared spectroscopy(FT-IR),inhibition zone method,oscillation flask method and transmission electron microscope(TEM).FT-IR test showed that the TP and PLA combined well by valence bonds on PLA/TP nanofiber membrane.Antibacterial experiment indicated that the antibacterial performance of the membrane increased as TP content increased.The widths of inhibition zone against Escherichia coli and Staphylococcus aureus increased from 3.67 and 3.71 cm to 5.17 and 5.67cm respectively.The inhibitory rate increased from 20.6% and 21.3% to 96.9%and 97.6% respectively.TEM examination indicated that PLA/TP composed nanofiber membrane can destroy the integrity of cell membrane of bacteria and finally lead to the death of bacteria.