Comparative analysis of volatile oils in the stems and roots of Ephedra sinica via GC-MS-based plant metabolomics / 中国天然药物

With a great difference in therapeutic effects of Mahuang (MH, the stems of Ephedra sinica) and Mahuanggen (MHG, the roots of Ephedra sinica), chemical differences between MH and MHG should be investigated. In the present study, gas chromatography-mass spectrometry (GC-MS)-based plant metabolomics was employed to compare volatile oil profiles of MH and MHG. The antioxidant activities of volatile oils from MH and MHG were also compared. 32 differential chemical markers were identified according to the variable importance in the projection (VIP) value of orthogonal partial least squares discriminant analysis (OPLS-DA) and P value of Mann-Whitney test. Among them, chemical markers of tetramethylpyrazine (TMP) and α-terpineol were quantified. Their contents were much higher in most MH samples compared with MHG. The antioxidant assay demonstrated that MH had significantly higher free radical-scavenging activity than MHG. Although MH and MHG derived from the same medicinal plant, there was much difference in their volatile oil profiles. MH samples had significantly higher content of two reported pharmacologically important chemical markers of TMP and α-terpineol, which may account for their different antioxidant activities.

A new quinoline alkaloid from the roots of Dictamnus angustifolius / 中国天然药物

AIM@#To investigate the quinoline alkaloids from the roots of Dictamnus angustifolius G.Don ex Sweet (Rutaceae).@*METHOD@#The quinoline alkaloids were isolated by various column chromatographic methods and their structures were elucidated on the basis of spectral analysis.@*RESULTS@#A new quinoline alkaloid, 5-methoxylrobustine (1), along with five known quinoline alkaloids were obtained, and their structures were identified as dictamnine (2), robustine (3), isopteleine (4), γ-fagarine (5), and skimmianine (6). Cytotoxicity testing of these alkaloids showed that all of them had weak cytotoxic activities against human breast cancer cells (MCF7).@*CONCLUSION@#Compound 1 is a new quinoline alkaloid. Alkaloid 3 showed stronger anti-proliferation effect than the other alkaloids.