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Yongjia Shen - One of the best experts on this subject based on the ideXlab platform.

Xiao Wang - One of the best experts on this subject based on the ideXlab platform.

  • Preparative Separation of caffeoylquinic acid isomers from lonicerae japonicae flos by ph zone refining counter current chromatography and a strategy for selection of solvent systems with high sample loading capacities
    Journal of Chromatography A, 2018
    Co-Authors: Hongjing Dong, Lan-ping Guo, Hengqiang Zhao, Xiao Wang
    Abstract:

    Caffeoylquinic acid derivatives exhibit anti-inflammatory, antioxidant, and antibacterial activities. We successfully applied pH-zone-refining counter-current chromatography (pH-ZRCCC) to Separation of isomeric caffeoylquinic acids from Lonicerae japonicae Flos using a two-phase solvent system composed of ethyl acetate-n-butanol-acetonitrile-water (3:1:1:5, v/v/v/v). Trifluoroacetic acid (10 mM) was added to the upper phase as a retainer and ammonium hydroxide (10 mM) was added to the lower phase as an eluter. As a result, 167.8 mg of chlorogenic acid, 15.9 mg of isochlorogenic acid B, 103.4 mg of isochlorogenic acid C, and 156.0 mg of isochlorogenic acid A were obtained from 1.2 g of crude extract, and all compound purities were over 96%. In addition, by comparing the numeric values of partition coefficient of compounds, it was found that larger differences between the K values of adjacent compounds in the solvent systems resulted in higher sample loading capacities. pH-ZRCCC method is an efficient Preparative Separation of isomeric caffeoylquinic acids from natural products.

  • Semi-Preparative Separation of 10 Caffeoylquinic Acid Derivatives Using High Speed Counter-Current Chromatogaphy Combined with Semi-Preparative HPLC from the Roots of Burdock (Arctium lappa L.).
    Molecules, 2018
    Co-Authors: Zhenjia Zheng, Hongjing Dong, Xiao Wang, Pengli Liu, Li Meng, Xuguang Qiao
    Abstract:

    Burdock roots are healthy dietary supplements and a kind of famous traditional Chinese medicine, which contains large amounts of caffeoylquinic acid derivatives. However, little research has been reported on the Preparative Separation of these compounds from burdock roots. In the present study, a combinative method of HSCCC and semi-Preparative HPLC was developed for the semi-Preparative Separation of caffeoylquinic acid derivatives from the burdock roots. The ethyl acetate extract of burdock roots was first fractionated by MCI macroporous resin chromatography and give three fractions (Fr. 1–3) from the elution of 40% methanol. Then, these three fractions (120 mg) were separately subjected to HSCCC for purification with the solvent system composed of petroleum ether-ethyl acetate-methanol-water at different volume ratios, and the mixtures were further purified by semi-Preparative HPLC. As a result, a total of eight known caffeoylquinic acid derivatives including 3-O-caffeoylquinic acid (32.7 mg, 95.7%), 1,5-O- dicaffeoylquinic acid (4.3 mg, 97.2%), 3-O-caffeoylquinic acid methyl ester (12.1 mg, 93.2%), 1,3-O-dicaffeoylquinic acid (42.9 mg, 91.1%), 1,5-O-dicaffeoyl-3-O-(4-maloyl)-quinic acid (4.3 mg, 84.5%), 4,5-O-dicaffeoylquinic acid (5.3 mg, 95.5%), 1,5-O-dicaffeoyl-3-O-succinylquinic acid (8.7 mg, 93.4%), and 1,5-O-dicaffeoyl-4-O-succinylquinic acid (1.7 mg, 91.8%), and two new compounds were obtained. The new compounds were 1,4-O-dicaffeoyl-3-succinyl methyl ester quinic acid (14.6 mg, 96.1%) and 1,5-O-dicaffeoyl-3-O-succinyl methyl ester quinic acid (3.1 mg, 92.6%), respectively. The research indicated that the combination of HSCCC and semi-Preparative HPLC is a highly efficient approach for Preparative Separation of the instability and bioactive caffeoylquinic acid derivatives from natural products.

  • Preparative Separation of Chelerythrine and Sanguinarine from Macleaya cordata by pH-Zone-Refining Counter-current Chromatography
    Journal of Liquid Chromatography & Related Technologies, 2015
    Co-Authors: Qian Liu, Changlei Sun, Fansheng Meng, Wei Zhao, Xiao Wang
    Abstract:

    Chelerythrine and sanguinarine are the representative and major active constituents of Macleaya cordata. Few reports regarding the Preparative Separation of these two alkaloids from this Chinese herbal medicine were found. In the present study, an efficient method was established to separate chelerythrine and sanguinarine from Macleaya cordata by pH-zone-refining counter-current chromatography. The crude sample was separated into two fractions, which corresponded to chelerythrine (a) and sanguinarine (b) with the two-phase solvent system chloroform–ethyl acetate–methanol–water (3:1:3:2, v/v/v/v) where 10 mM HCl was added in the upper phase and 10 mM trithylamine in the lower phase. From 2.0 g of crude extract, chelerythrine (600 mg) and sanguinarine (750 mg) were obtained in a single run with the purity of both over 95.0% as determined by HPLC. The chemical structures were confirmed by electrospray ionization-mass spectrometry, 1H NMR and 13C NMR.

  • Acid-Alkali Extraction of Triterpene Acids from Poria and Preparative Separation by High-Speed Counter-Current Chromatography
    Separation Science and Technology, 2014
    Co-Authors: Hongjing Dong, Renyi Yan, Weihao Wang, Xiao Wang, Bin Yang
    Abstract:

    A method for the acid-alkali extraction and Preparative Separation of triterpene acids from poria was established. The triterpene acids were enriched and separated into two fractions after extraction at the optimized pH value. The two fractions were subjected to high-speed counter-current chromatography for the Preparative Separation of triterpene acids, separately. As a result, dehydropachymic acid, pachymic acid, 3-epi-dehydropachymic acid, poricoic acid B, dehydrotumulosic acid, and 3-epi-dehydrotumulosic acid were obtained with purities of 94.1%, 96.2%, 93.5%, 85.9%, 80.1%, and 93.1%, respectively. The structures were identified by ESI-MS, 1H NMR, and 13C NMR.

  • Preparative Separation of quaternary ammonium alkaloids from coptis chinensis franch by ph zone refining counter current chromatography
    IEEE Journal of Solid-state Circuits, 2011
    Co-Authors: Jia Li, Xiao Wang, Wenjuan Duan, Tian You Zhang
    Abstract:

    pH-Zone-refining counter-current chromatography was successfully applied to the Preparative Separation of five quaternary ammonium alkaloids from the crude extract of Coptis chinensis Franch. The Separation was performed with a two-phase solvent system composed of chloroform–methanol–water (4:3:3, v/v), where the upper aqueous stationary phase was added with 60 mM of hydrochloric acid and the lower organic mobile phase with 5 mM of triethylamine. From 1.0 g of crude extract, 5.4 mg of columbamine at 96.6% purity, 6.1 mg of jateorhizine at 98.8% purity, 58.3 mg of coptisine at 99.5% purity, 25.6 mg of palmatine at98.4% purity and 503.9 mg of berberine at 99.5% purity were obtained. The purities of the isolated alkaloids were analyzed by HPLC and the chemical structures were identified by electrospray ionization-mass spectrometry and 1H-NMR.

Tianhui Huang - One of the best experts on this subject based on the ideXlab platform.

Pingniang Shen - One of the best experts on this subject based on the ideXlab platform.

Yuangang Zu - One of the best experts on this subject based on the ideXlab platform.

  • Preparative Separation of dryofragin and aspidin bb from dryopteris fragrans extracts by macroporous resin column chromatography
    Journal of Pharmaceutical and Biomedical Analysis, 2012
    Co-Authors: Xiaojuan Li, Yujie Fu, Wei Wang, Lin Zhang, Chunjian Zhao, Yuangang Zu
    Abstract:

    Abstract A simple, efficient and environment-friendly chromatographic Separation method was developed for Preparative Separation and enrichment of dryofragin and aspidin BB from Dryopteris fragrans. The adsorption properties of twelve macroporous adsorption resins were evaluated. The three selected resins were further screened depending on the Separation performance of their packed columns, in which AB-8 resin showed better Separation efficiency for dryofragin and aspidin BB. In order to maximize column efficiency, the operating parameters (flow rate, ethanol concentration and volume) of the resin column chromatography were optimized and compared with the conventional resin column adsorption. After Preparative Separation and enrichment on resin column chromatography, the contents of dryofragin and aspidin BB in the product were 8.39- and 5.99-fold increased with recovery yields of 91.22% and 75.64%, respectively. Moreover, the regenerated adsorbent exhibited excellent reusability within at least five cycles of adsorption/desorption. It suggested that multi-targets would be enriched effectively by resin column chromatography.

  • Preparative Separation and enrichment of four taxoids from taxus chinensis needles extracts by macroporous resin column chromatography
    Journal of Separation Science, 2009
    Co-Authors: Kusng Fu, Shuangming Li, Yuangang Zu, Yujie Fu, Ying Wang, Zhengnan Li
    Abstract:

    An environment-friendly method was established for the Preparative Separation and enrichment of four taxoids, namely 10-deacetylbaccatin III (10-DAB III), 7-xylosyl-10-deacetyltaxol (7-xyl-10-DAT), cephalomannine and paclitaxel from Taxus chinensis needles extracts. Characteristics of seven widely used macroporous resins for four taxoids were compared, AB-8 resin offered better adsorption and desorption capacities than others. AB-8 resin column chromatography was used to study the desorption process for four taxoids. The optimum parameters for desorption were 30% ethanol 5 RV for removing impurities, following 15 RV for 10-DAB III, after the desorption of impurities with 35% ethanol 10 RV, 45% ethanol 30 RV for 7-xyl-10-DAT, then 65% ethanol 10 RV for cephalomannine and paclitaxel, the flow rate was 6 RV/ h. After Separation on AB-8 resin column chromatography, the contents of 10-DAB III, 7-xyl-10-DAT, cephalomannine and paclitaxel in the product reached 4.58, 13.17, 1.36 and 3.08%, respectively, which were 7.63-, 3.68-, 6.18- and 6.55-fold to those in T. chinensis needles extracts. The recovery yields were 94.96, 77.32, 88.09 and 95.25%. In general, the AB-8 resin column chromatography has the advantages of lower cost, high efficiency and simple procedure. Therefore, it may provide scientific references for the Preparative Separation and enrichment of taxoids from other T. species.

  • Preparative Separation of vitexin and isovitexin from pigeonpea extracts with macroporous resins
    Journal of Chromatography A, 2007
    Co-Authors: Yujie Fu, Yuangang Zu, Shuangming Li, Liyan Chen, Meihong Tong
    Abstract:

    Abstract Vitexin and isovitexin are a pair of isomeric compounds known as the major constituents in pigeonpea leaves and possess various pharmacological activities. In the present study, the Preparative Separation of vitexin and isovitexin with macroporous resins (Nankai Hecheng S & T, Tianjin, China) was studied. The performance and adsorption characteristics of eight macroporous resins including ADS-5, ADS-7, ADS-8, ADS-11, ADS-17, ADS-21, ADS-31 and ADS-F8 have been evaluated. The research results indicate that ADS-5 resin is most appropriate for the Separation of vitexin and isovitexin. Langmuir and Freundlich isotherms were used to describe the interactions between solutes and resin at different temperatures, and the equilibrium experimental data were well fitted to the two isotherms. Column packed with ADS-5 resin was used to perform dynamic adsorption and desorption tests to optimize the Separation process. The optimum parameters for adsorption were as follows: the concentration of vitexin and isovitexin in sample solution: 0.22 and 0.40 mg/mL, respectively, processing volume: 3 BV, flow rate: 1 mL/min, pH 4, temperature: 25 °C; for desorption: ethanol–water (40:60, v/v), 5 BV as an eluent, flow rate: 1 mL/min. After one run treatment with ADS-5 resin, the contents of vitexin and isovitexin were increased 4.07-fold and 11.52-fold from 0.86%, 1.53% to 3.50% and 17.63%, the recovery yields were 65.03% and 73.99%, respectively. In conclusion, the Preparative Separation of vitexin and isovitexin can be easily and effectively achieved via adsorption and desorption on ADS-5 resin, and the method can be referenced for the Separation of other flavone C -glucosides from herbal materials.