[Study on the chemical constituents of Cudrania tricuspidata].

OBJECTIVE: To study on the chemical constituents of Cudrania tricuspidata. METHODS: The chemical constituents were separated by means of silica gel and Sephadex LH-20 chromatography, and their structures were identified by spectra of 1H-NMR, 13 C-NMR. RESULTS: Seven compounds were isolated and identified as Quercetin (I),5,7,4'-trihydroxyldihydroisoflavone (II), (13alpha, 14beta, 17alpha, 20R)-Lanosta-7, 24-diene-3beta-ol (III), (13alpha, 14beta,17alpha, 20R)-Lanosta-7,24-diene-3beta-0-acetate (IV), Taxifolin (V), Dihydromorin (VI), Cycloartocarpin(VII). CONCLUSION: Compounds III and IV are isolated from the genus for the first time.

Quality Evaluation of Branches of Juglans mandshurica by HPLC-DAD Fingerprint Combined with HPLC-Q-TOF-MS/MS Characterization of Constituents / 中国实验方剂学杂志

Objective:To establish a high performance liquid chromatography （HPLC） fingerprint of branches of <italic>Juglans mandshurica</italic> and to evaluate the quality of the samples from different producing areas and in different harvest periods. Method:Chromatographic separation was performed on an Agilent Poroshell 120 SB-C₁₈ column （2.1 mm×100 mm， 2.7 μm） for gradient elution with mobile phase of 0.2% formic acid solution （A）-0.2% formic acid acetonitrile solution （B） （0-5 min， 5%-10%B； 5-25 min， 10%-16%B； 25-40 min， 16%-22%B； 40-45 min， 22%-45%B； 45-50 min， 45%-65%B； 50-52 min， 65%-100%B； 52-55 min， 100%B） at a flow rate of 0.3 mL·min^-1. The column temperature was 30 ℃ and the detection wavelength was 270 nm. The quality of branches of <italic>Juylans mandshurica</italic> was evaluated by similarity evaluation， cluster analysis， principal component analysis and partial least squares-discriminant analysis. The chemical constituents of the samples were identified by HPLC coupled with quadrupole time-of-flight mass spectrometry （HPLC-Q-TOF-MS/MS）. The mass spectrometry was conducted in negative ion mode with electrospray ionization（ESI）. Data were acquired over a range of <italic>m</italic>/<italic>z</italic> 100-1 700 for MS and <italic>m</italic>/<italic>z</italic> 50-1 700 for MS/MS. Result:A total of 19 common peaks were confirmed in 40 batches of samples， and the similarity ranged from 0.430 to 0.995， of which the similarity of samples collected in spring and winter seasons （April， May and December） was greater than 0.90， while the similarity of most samples collected in summer （July to September） was low. Multivariate statistical analysis showed that the samples were divided into two groups according to the harvest time， but there was no obvious classification rule for the samples from different producing areas. The contents of most constituents in the samples collected in spring and winter were higher than those collected in summer. The result illustrated that different harvest periods had great influence on the quality of branches of <italic>J</italic>.<italic> mandshurica</italic>. Compared with the samples collected in summer， the quality of samples collected in spring and winter was better. A total of 22 peaks were proved to be the main constituents that contributed to the difference between samples collected in different seasons. A total of 83 chemical components were identified by HPLC-Q-TOF-MS/MS， including 49 tannins， 7 organic acids， 14 naphthalene derivatives， 1 flavonoid， 6 anthracene derivatives， 2 lignans， 3 diarylheptanoids and 1 saccharide. Totally 13 common peaks were identified. Of the peaks that contributed to discriminate samples collected in different season， 19 peaks were identified and most of them were tannins. Conclusion:The established HPLC fingerprint can provide useful information for the quality evaluation of branches of <italic>J</italic>.<italic> mandshurica</italic>. Tannin is the main constituents in the samples. Harvest period has great influence on the quality of branches of <italic>J</italic>.<italic> mandshurica</italic>.

Determination of taxifolin in Polygonum orientale of different storage period / 中国中药杂志

<p><b>OBJECTIVE</b>To find out the correlation between the content of taxifolin in Polygonum orientale and the storage time.</p><p><b>METHOD</b>HPLC was used to determine taxifolin. The chromatographic condition was as following: Diamonsil C18 column (4.6 mm x 200 mm, 5 microm), mobile phase acetonitrile -0.1% phosphoric acid (gradient elution), the detection wavelength 290 nm and flow rate 1.0 mL x min(-1), the column temperature 30 degrees C.</p><p><b>RESULT</b>The injection volume of taxifolin was in good linearity within 0.07 and 0.35 microg, the average recovery was 99.7% with RSD 0.2%. Taxifolin content was 0.84, 1.36, 1.75, 1.99 mg x g(-1) corresponding to storage time of 10, 7, 6, 5 years, respectively.</p><p><b>CONCLUSION</b>The content of taxifolin decreased with the storage time. When the storage period is more than six years, the content is lower than that required by Chinese Pharmacopoeia (2010 version). This method has a good repeatability and accuracy, it provides a scientific reference for clinical use and quality evaluation of P. orientale.</p>

Simultaneous determination of four flavones in root and stem of Cudrania tricuspidata and C. cochinchinensis by HPLC-DAD / 中国中药杂志

<p><b>OBJECTIVE</b>To establish a HPLC-DAD method for the determination of axifolin, naringenin, quercetin and kaempferol in Cudrania tricuspidata and C. cochinchinensis in order to provide a scientific reference for species identification and quality evaluation, by establishing.</p><p><b>METHOD</b>The determination was performed by HPLC-DAD on an Agilent C18 column (4.6 mm x 150 mm, 5 microm) by gradient elution (0-15 min, 35%-50% A; 15-30 min, 50% - 65% A) using methanol (A) and 0.1% phosphoric acid (B) as the mobile phase. The flow rate was 1 mL x min(-1). The detection wavelength was 290 nm for taxifolin and naringenin, 365 nm for quercetin and kaempferol with column temperature at 30 degrees C.</p><p><b>RESULT</b>The content of axifolin and quercetin in the root of C. tricuspidata were remarkably higher than that in the root of C. cochinchinensis, and the content in stem of C. tricuspidata was also higher than that in the stem of C. cochinchinensis, the content of axifolin and quercetin was variable in different species. The content of naringenin and kaempferol in the root of C. cochinchinensis was visibly higher than that in the root of C. tricuspidata, and the content in the stems of the two herbs was similar, the content of naringenin and kaempferol was visibly variable in different medicinal parts of the herb, but similar between the two herbs.</p><p><b>CONCLUSION</b>There's some difference of the content of the four ingredients in different medicinal parts and different herbs, so clinical use should not be confused.</p>