Comparison of Bacteriostatic Effects of Different Extracts from Fructus amomi and Its Salt-processed Products

The crude extracts of Fructus amomi and its salt-processed products were obtained by beating into powder and sieveing,ultrasonic extraction assisted by different concentrations of ethanol and then fractional extraction with petroleum ether,ethyl acetate or n-butanol. The crude extracts were used to test bacteriostatic effect through diameter of bacteriostatic circle and minimum bacteriostatic concentration against three strains(E. coli,S. aureus and B. subtilis). The results showed that 95% ethanol extracts of salt-processed Fructus amomi had better bacteriostatic effect than 75% and 65% ethanol extracts. In addition,the bacteriostatic effect of different ethanol extracts of Fructus amomi were better than that of salt-processed Fructus amomi against the three test strains. Among the different solvent extracts,petroleum ether extracts of Fructus amomi and salt-processed products had the best bacteriostatic effect,particular in B. subtilis,and the inhibition zone diameters were 14.83 and 12.11 mm,respectively. Correspondingly,the minimum inhibitory concentrations(MIC)of petroleum ether extracts of Fructus amomi and salt-processed products on B. subtilis were 0.23 and 0.44 mg/mL,respectively. The bacteriostatic effect of different extracts of Fructus amomi is better than that of salt-processed Fructus amomi on the three strains.