Anti-acetylcholinesterase Active Ingredients from Aconitum tanguticum by UPLC-Q-TOF-MS/MS / 中国实验方剂学杂志

Objective:To identify the anti-acetylcholinesterase active ingredients in <italic>Aconitum tanguticum</italic>， so as to lay the foundation for finding new anti-Alzheimer's disease （AD） drugs. Method:The anti-acetylcholinesterase active fractions of <italic>A. tanguticum</italic> were screened by the modified Ellman's method， and the chemical composition of the active fraction was analyzed by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry （UPLC-Q-TOF-MS/MS）. The chromatographic separation was performed on an ACQUITY UPLC BEH C₁₈ column （2.1 mm×50 mm， 1.7 μm） with acetonitrile （A）-0.4% ammonia aqueous solution （B） as mobile phase for gradient elution， and the column temperature was set at 30 ℃ with the flow rate of 0.4 mL·min^-1. Phase A of the dichloromethane fraction changed with time as follows：0-3 min， 5%A； 3-7 min， 5%-20%A； 7-11.5 min， 20%-33%A； 11.5-15.5 min， 33%-50%A； 15.5-20.5 min， 50%-80%A； 20.5-23 min， 80%-85%A； 23-25 min， 85%-95%A. Phase A of the <italic>n</italic>-butanol fraction changed with time as follows：0-2 min， 5%A； 2-8 min， 5%-20%A； 8-11 min， 20%-33%A； 11-15 min， 33%-95%A. Mass spectrometry was performed on electrospray ionization， data were collected in positive ion mode， and the detection range was <italic>m</italic>/<italic>z</italic> 100-1 500. Result:Both the dichloromethane and <italic>n</italic>-butanol fractions had a certain inhibitory effect on acetylcholinesterase， their half inhibitory concentration （IC₅₀） values were （64±4.4） mg·L^-1 and （85.7±3.8） mg·L^-1， respectively. By UPLC-Q-TOF-MS/MS analysis， a total of 21 alkaloids were identified from the dichloromethane fraction， and 11 alkaloids were identified from <italic>n</italic>-butanol fraction. Guan-fu base Ⅰ， found in both fractions， was first discovered in <italic>A. tanguticum</italic>. Conclusion:Diterpene alkaloids are the main anti-acetylcholinesterase substances of <italic>A. tanguticum</italic>， which is worth further exploration.

A novel dimeric diterpenoid alkaloid from the Tibetan medicinal plant Aconitum tanguticum (Maxim.) Stapf / 药学学报

Two dimeric diterpenoid alkaloids were isolated from the whole plant of Aconitum tanguticum (Maxim.) Stapf and their structures were elucidated by extensive analysis of 1D, 2D-NMR and HR-MS data. One is a new compound and named tanguticurine A (1), and the other is the known compound anthoroidine B (2); both were isolated from this plant for the first time. The antiviral activity of compounds 1 and 2 against HCV and EV71 were also evaluated. It was found that compound 1 had a good inhibitory effect on HCV and EV71 with EC50 values of 15.5 and 9.7 μmol·L-1, respectively, and showed low cytotoxicity. Therefore, compound 1 is a good antiviral lead compound and deserves further study.

HPLC fingerprint of Tibetan medicinal plant ″Bangga″ and chemical components analysis of its two original plants by LC-MS/MS / 中国中药杂志

To obtain the chemical profile of Tibetan medicinal plant ″Bangga″, the present study established the HPLC fingerprint of ″Bangga″ and inferred common chemical constituents of its two original plants, Aconitum tanguticum and A. naviculare by LC-MS. The HPLC analysis was performed on a Kromasil 100 C_8 column(4.6 mm×250 mm, 5 μm) with acetonitrile(A)-0.1% formic acid in water(B) as mobile phase in a gradient elution mode. Besides, the flow rate was set at 1 mL·min~(-1) and the column temperature was 35 ℃. The detection wavelength was set at 255 nm and the injection volume was 10 μL. Seventeen batches of ″Bangga″ samples were analyzed and the HPLC fingerprint was established under the above conditions. Similarity evaluation was performed using Similarity Evaluation System for Chromatographic Fingerprint of Traditional Chinese Medicine(2012). As a result, 16 common peaks were selec-ted and the similarity values of 17 batches of ″Bangga″ were in the range of 0.702-0.966. Furthermore, one batch of A. tanguticum and one batch of A. naviculare were analyzed by LC-MS/MS and 74 common compounds were inferred, including 10 phenolic acids, 26 flavonoids, and 38 alkaloids. The established method, with good separation and strong specificity, is simple and feasible, and can be used for the quality control of ″Bangga″ and identification of its two original plants. A. tanguticum and A. naviculare are similar in chemical composition and component content, but are quite different in the content of flavonoids.