[GC-MS analysis of essential oil from rhizomes of Ligusticum chuanxiong cultivated in GAP base for Chinese medicinal materials of China].

OBJECTIVE

To analyze the constituents of the essential oil extracted from the rhizomes of Ligusticum chuanxiong. cultivated in "GAP base for Chinese medicinal materials of China" (GAP demonstrative base of L. chuanxiong in Dujiangyan City of China), and to provide scientific foundation for the quality control and standard establishment of ones.

METHOD

The essential oil was extracted by water-steam distillation and separated by GC capillary column chromatography. The components were determined with normalization method, and identified by GC-MS and co-artificial searches.

RESULT

One hundred forty-two chromatographic peaks were isolated, among them sixty-two components were identified, which was composed of 87.36% of the total essential oil. The mass fragmentation rules of phthalides and its derivatives in the essential oil were summarized, which primarily underwent two electron impact fragmentation pathways: side-chain cleavage with losses of alkenes/alkanes and ring-opening with elimination of H2O followed by losses of CO. On the basis of these rules, the plane structure of 4, 5-dihydro-3, 1 '-dihydroxy-3-pentylphthalide as a new compound was determined.

CONCLUSION

The main components of the essential oil extracted from the rhizomes of L. chuanxiong cultivated in "GAP Demonstrative Base of L. chuanxiong in Dujiangyan City of China" were phthalides and its derivatives. 4,5-Dihydro-3,1'-dihydroxy-3-pentylphthalide was a new compound.