Objective: To study the differences of chemical composition and antibacterial activity between Zedoary Turmeric oil and dregs residual oil

and provide scientific basis for full use of Curcuma wenyujin dregs. Method: The Zedoary Turmeric oil and the dregs residual oil were extracted by hydrodistillation and separated by capillary GC-MS. The chemical compositions were determined by normalization and were identified by MS. Their antibacterial activity was determined by using micro-dilution method. Result: For Zedoary Turmeric oil

78 chromatographic peaks were detected and 29 compounds were identified

accounting for 86.68% of the total composition. For dregs residual oil

78 chromatographic peaks were detected and 31 compounds were identified

accounting for 70.83% of the total composition. Zedoary Turmeric oil showed inhibitory activity against Escherichia coli and Staphylococcus aureus with the same MIC value of 50.5 mg·L-1;dregs residual oil showed inhibitory activity against M. tetragenus

E. coli and S. aureus with the same MIC value of 44.4 mg·L-1. Conclusion: It is the first time to contrast the differences of chemical composition and antibacterial activity between Zedoary Turmeric oil and dregs residual oil. Chemical composition analysis shows that their main chemical ingredients are similar

including elemene

germacrone

curzerene

curdione

neocurdione etc. The antifungal activity shows that dregs residual oil is in general stronger than Zedoary Turmeric oil. The experiment scientific basis were provided for the further research and utilization of the C. wenyujin dregs.