Comparison of volatile compositions among four related Ligusticum chuanxiong herbs by HS-SPME-GC-MS

Chuanxiong (CX, Ligusticum chuanxiong), Japanese Chuanxiong (JCX, Cnidium officinale), Fuxiong (FX, Ligusticum sinense 'Fuxiong'), and Jinxiong (JX, Ligusticum sinense 'Jinxiong') are aromatic herbs used in China, Japan, and other regions. Their morphology and aromatic odor are similar, resulting in confused and mixed uses. This study compares the volatile compositions of these herbs for defining their medical uses. Headspace solid-phase microextraction-gas chromatography-triple quadrupole-mass spectrometry was employed to separate, identify, and quantify the compounds in the volatile gas of the four herbs. A total of 128 volatile compounds were identified and quantified in 23 these herbal samples. The sums of 106, 115, 116, and 120 compounds were detected in the volatile gas of CX, JCX, FX, and JX, with the mean contents of 4.80, 7.12, 7.67, and 12.0 μg/g, respectively. Types and contents of the main compounds were found to be different in the volatile gas of these herbs. The orthogonal partial least squares discriminant analysis and hierarchical clustering analysis showed the four herbs located in different confined areas or clusters. It is concluded that the volatile compositions in the four herbs are generally similar, but the contents of main volatile compounds are different. These herbs should be clearly differentiated in medical use.