Rapid determination of essential oil in Acorus tatarinowii Schott. by pressurized hot water extraction followed by solid-phase microextraction and gas chromatography-mass spectrometry.

A simple, rapid, efficient and inexpensive method for the determination of essential oil in a traditional Chinese medicine (TCM), Acorus Tatarinowii Schott. was developed by using pressurized hot water extraction (PHWE) combined with solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS). Acorus Tatarinowii Schott. (0.050 g) was subjected to dynamic extraction with water at 50 bar, 150 degrees C and 1.0 ml/min for 5.0 min, and then the essential oil in the aqueous extract were extracted by SPME fibers at 60 degrees C for 10 min, finally the compounds on the fiber were desorbed and analyzed by GC-MS. The PHWE and SPME parameters were studied. The key active compound of alpha-asarone in the TCM samples from three different growing areas was quantitatively analyzed by external standard method. Compared to steam distillation (SD), the proposed method required little time (only 15 min) to prepare sample. Moreover, little sample mass and no organic solvent was needed. The present method provided good repeatability (R.S.D. less than 13.0%) and recovery (92% for alpha-asarone). It has been shown that PHWE-SPME-GC-MS is an alternative method for determination of essential oils in TCMs and a potential tool for TCM quality assessment.