Content changes regularity of flavonoids in Smilax glabra by QAMS method / 中草药

Objective: To establish a method of quantitative analysis of multi-components by single-marker (QAMS) for simultaneously determination of neoastilbin, astilbin, neoisoastilbin, isoastilbin, and engeletin in Smilax glabra, and research the tendency of content changes in different growth years by QAMS. Methods: An HPLC method was established to determine the relative correction factors of four other flavonoids by using astilbin as the internal reference standard. Then the method was used to determine the various content of five flavonoids in different growth years and validate the feasibility and accuracy by comparing the content results determined by the external standard method with QAMS. The dynamic change regularity of flavonoids in S. glabra was investigated. Results: A total of 23 samples from five batches in different growth years were simultaneously determined by external standard method and QAMS, the results deviation were all less than 1.0%. The content of five flavonoids in different growth years was different, astilbin decreased with the increase of growth years, neoastilbin, neoisoastilbin and isoastilbin had the reverse trend. Conclusion: The established QAMS method is feasible and accurate for the simultaneous determination of five flavonoids in S. glabra. Growth years have a certain impact on the content of each component.

Flavanoids from the leaves of Engelhardtia roxburghiana / 中国药学杂志

OBJECTIVE: To investigate the chemical constituents of the leaves of Engelhardtia roxburghiana. METHODS: After the plant materials were extracted and fractionated with solvents, column chromatography was used to isolate and purify the compounds. The structures were elucidated on the basis of 1H-NMR, 13C-NMR, MS analysis and comparison with the literature data. RESULTS: Thirteen compounds were identified as following; taxilfolin (1), 5,7,4'-trihydroxy flavanone(2), kaempferol (3), dihydrokaempferol (4), quercetin(5), isoengeletin(6), engeletin (7), astilbin(8), isoastilbin(9), kaempferol-3-O-α-L-rhamnoside(10), eucryphin (11), 5-hydroxy-3,7,3',4'-tetramethoxyflavone(12), quercetin-3-O-α-L-rhamnoside (13). CONCLUSION: Compounds 2, 4, 9, 11 and 12 were identified from the title plant for the first time.