[Water extraction coupling rectification for isolating volatile oils of Ligusticum chuanxiong]

To improve the oil yield of Chuanxiong volatile oils and keep their quality same as that of oils prepared by steam distillation (SD) for short), a new technology of coupling water extraction and rectification (WER for short) was applied to isolate Chuanxiong volatile oils. The oil yield, as well as GC-MS chromatogram of the volatile oils extracted by WER and SD were compared. The oil yield of WER (0.50%) was that of SD (0.20%). There were 21 common constituents in the two kinds of volatile oils, which occupied 98.94% of the oils extracted by SD, 98.80% of that by WER, respectively. Moreover, the relative percentage of the common constituents was almost the same. The results indicate that WER could not only increase the oil yield of Ligusticum chuanxiong, but also keep the quality of the oils accord with that extracted by SD.