Extrication process of chlorogenic acid in Crofton weed and antibacterial mechanism of chlorogenic acid on Escherichia coli.

Crofton weed is a perennial herb and a biological intruding species. The present study firstly used the orthogonal test to compare the differences in extraction of chlorogenic acid in leaves and stems of Crofton weed by using three kinds of solvents, namely water, ethanol and ethyl acetate. The best effect was found by using ethonolic extraction of chlorogenic acid in Crofton weed. Further, by choosing Escherichia coli as test object, in-vitro antibacterial test was conducted to study the antimicrobial activities of chlorogenic acid by testing a series of indexes before and after the interaction between chlorogenic acid and Escherichia coli, to clarify the antibacterial mechanism of chlorogenic acid on Escherichia coli. Finally, by comparing the antibacterial activities of isochlorogenic acid A on Escherichia coli, it was concluded that both chlorogenic acid and isochlorogenic acid A showed antibacterial activities against Escherichia coli, wherein chlorogenic acid had a better antibacterial effect on Escherichia coli than isochlorogenic acid A.