Objective: To investigate the antimicrobial fractions of Galla Chinensis. Method: The minimum inhibitory concentrations (MICs) of portions of petroleum ether

chloroform

ethyl acetate

n-butanol

ethanol and water of Galla Chinensis against five bacterias and Candida albicans were determined by agar dilution method. The data were analyzed using statistical software SPSS 17.0

and multifactor analysis of variance (ANOVA) and independent samples t test were used to compare the differences between 2 active fractions of ethyl acetate

n-butanol against same bacterial species

and between Clotrimazole and ethyl acetate fraction of Galla Chinensis against C. albicans. Result: The 3 portions of petroleum ether

chloroform and ethanol of Galla Chinensis had no effect on bacteria and C. albicans

and water fraction only had weak activity against S. aureus

with MICs 733.69 g·L-1

n-butanol fraction only had antibacterial activity

with MICs ranging from 2.06 g· L-1 to 32.96 g· L-1. However

ethyl acetate fraction of Galla Chinensis had strong antibacterial and antifungal activities

with MICs ranging from 2.88-23.07 g· L-1 and 0.36-27.28 g· L-1

respectively. The ethyl acetate fraction and n-butanol fraction of Galla Chinensis had higher activity against Gram-positive isolates than Gram-negative isolates (P<0.01

P<0.05)

and the two active-fractions had similar antibacterial activity against sensitive and resistant bacteria. The ethyl acetate fraction of Galla Chinensis had strong effect on C. albicans from sensitive and resistant clinical isolates

with MICs ranging from 0.36 g· L-1 to 0.72 g· L-1

but the resistance rate of Clotrimazole was 14.29% (2/14). Conclusion: Antibacterial and antifungal active fraction of G.chinensis was ethyl acetate fraction

which had broad-spectrum antimicrobial activity so to make it a potential candidate as antimicrobial agent to treat infectious diseases.