Objective: To preparate the phillyrin and forsythiaside A from the n-butanol fraction of Qingqiao of Forsythia suspensa

and to explore their antibacterial activity and free DPPH radical scavenging capacity. Method: The phillyrin and forsythiaside A from the n-butanol fraction of Qingqiao were isolated and purified by means of silica gel column chromatography and recrystallization

etc. The antibacterial activity of phillyrin and forsythiaside A were tested against Escherichia coli

Staphylococcus aureus and Streptococcus pneumoniae by using K-B paper disk method. DPPH assay was employed to assess the antioxidant activity of the phillyrin and forsythiaside A. Result: The diameter of inhibition zone forming by forsythiaside A against E. coli

S. pneumoniae and S. aureus were 12.35

9.58

12.29 mm

respectively. In vitro antibacterial tests revealed that forsythiaside A exhibited better effect than n-butanol fraction of Qingqiao

but not good as gentamicin

and phillyrin didn't show any activity. Meanwhile

forsythiaside A was more potent against E. coli than other two strains. Morever

DPPH experimental results showed that forsythiaside A had higher free DPPH radical scavenging capacity than the phillyrin. Conclusion: Forsythiaside A showed a higher antibacterial activity and antioxidant activity in vitro than phillyrin

and it may be the main active components of Qingqiao.