Abstract: To determine the content of lawsone (HNQ) and 2-methoxy-1,4-naphthoquinone (MeONQ) and antifungal activities of five polar fractionsof ethanol extracts of Impatiens balsamina L.and analyze relationship between content and antifungal activities,in order to define antifungal active constituents of Impatiens balsamina L.The content and transfer rate of HNQ and MeONQ in different extraction parts was simultaneously determined by using HPLC method.The fungicidal activities of extracts of five fractions against Trichophyton rubrum were studied by filter paper diffusion method.The results showed that the petroleum ether extract showed the highest amount of HNQ and MeONQ,their content were 4.20% and 39.46%,and transfer rate were 53.46% and 92.52%,respectively.Secondly,the dichloromethane extraction,their content of HNQ and MeONQ were 2.44% and 0.38%,and transfer rate were 17.85% and 0.49%,respectively.However,ethtyl acetate,n-butanol and water solvent fractions all were hard to detect HNQ and MeONQ.The results of filter paper diffusion method showed that petroleum ether extract was the best,dichloromethane extraction was low antifungal activities,and the other three phases exhibited no antifungal activities.The results showed that antifungal activities were positively correlated to content of HNQ and MeONQ in different polar parts of Impatiens balsamina L.The content of HNQ and MeONQ the petroleum ether extract was the main antifungal active fractions,HNQ and MeONQ were the main active constituent.

Key words: Impatiens balsamina L., solvent extracts, trichophyton rubrum, antibacterial activity, lawsone, 2-methoxy-1,4-naphthoquinone