Abstract: To analysis the main antibacterial components in patchouli oil,based on the principle of Knock-out/Knock-in,aiming at the two targeted components(patchouli alcohol and patchoulenone),different samples containing different content and proportion of patchouli alcohol and patchoulenone were prepared.Minimal inhibitory concentration(MIC) of the samples against 6 gram-positive bacteria and 5 gram-negative bacteria were detected by standard ager dilution method.SAS 9.2 software was adopted to do univariate ANOVA,and each different two groups of data were compared by SNK method(q-test) combined with factorial design.The results showed that antibacterial effect of original patchouli oil were significantly better than the knocked-out negative sample;the knocked-out negative sample still remained a certain of antibacterial effect though the effect was decreased to some degree;the original patchouli oil,the positive sample(patchouli alcohol:patchoulenone = 2:1),patchouli alcohol and patchoulenone had almost the same effect;the antibacterial effect of patchouli alcohol against gram-positive bacteria was better than patchoulenone,while patchoulenone showed better effect than patchouli alcohol against gramnegative bacteria;patchouli oil with different proportion achieved quit different antibacterial effect.In conclusion,although other unknown components remain a certain degree of antibacterial effect,patchouli alcohol and patchoulenone were the main antibacterial components of patchouli oil;the two targeted compounds performed quite different activity against gram-positive bacteria and gram-negative bacteria;the effect of patchouli oil slightly changed by adjust the proportion between the two targeted compounds:with the proportion of patchoulenone increasing,the antibacterial effect trend to decrease for grampositive bacteria and trend to increase for gram-negative bacteria.

Key words: patchouli oil, Knock-out/Knock-in, patchouli alcohol, patchoulenone, antibacterial