Scaling up of high-speed countercurrent chromatographic apparatus with three columns connected in series for rapid preparation of (−)-epicatechin

Zong

et al. 2013

J. Sep. Science

Self Cite

Four flavonoids, isoastilbin, astilbin, isoengelitin, and engelitin were isolated and purified simultaneously from Smilacis Glabrae Roxb. for the first time by high performance counter-current chromatography using a system consisting of n-hexane-n-butanol-water (1:2:3, v/v/v). A total of 392.6 mg of astilbin, 71.4 mg of isoastilbin, 47.4 mg of engelitin, and 10.3 mg of isoengelitin were purified from 1.89 g of the ethyl acetate extract of Smilacis Glabrae Roxb. in six runs, each at over 94.51% purity as determined by HPLC. The structures of the four compounds were identified by their retention time, the LC-ESI-MS(n) in the negative ion mode, and confirmed by (1)H-NMR experiments. The characteristic LC-ESI-MS fragmentation patterns of the four compounds were discussed.

Section: Introductionmentioning

confidence: 99%

Preparative separation of flavonoids in plant extract of Smilacis Glabrae Roxb. by high performance counter-current chromatography

Zong

et al. 2013

J. Sep. Science

Self Cite

“…3c shows the HPLC chromatography of EGCG-and ECG-enriched fractions that were obtained with Method 5 by AB-8 resin. Although the two fractions were collected with low purity of EGCG and ECG, this simple method provides a cost-effective means to separate EGCG from ECG (Du et al, 2013;Cui et al, 2017). Furthermore, the method developed here clearly shows the advantage of dynamic elution over static adsorption.…”

Section: Resultsmentioning

confidence: 95%

“…Not only were the two compounds simultaneously separated with high purity and yield, the procedure is also simpler than those described in the literature (Bazinet et al, 2007;Yang et al, 2008;Lai et al, 2012;Du et al, 2013;Lai and Gu, 2014;Ye et al, 2014;Wang et al, 2014;Jin et al, 2015;Cui et al, 2017). Furthermore, only a dilution of ethanol and methanol were needed, which is considerably safer, cheaper and more environmentally friendly than the chemicals used in other methods (Yang et al, 2008;Lai et al, 2012;Du et al, 2013;Lai and Gu, 2014). Furthermore, most of catechin were collected with ECGenriched fractions by AB-8 resin and then purificated in the process of ECG purification by AB-β-CD (seeing the Fig.…”

Section: Resultsmentioning

confidence: 99%

Separation and Purification of Epigallocatechin Gallate and Epicatechin Gallate by Two-step Chromatography Involving <i>β</i>-cyclodextrin Bonded Agar

Liu

et al. 2019

FSTR

A novel method was developed to separate the tea polyphenols epigallocatechin gallate (EGCG) and epicatechin gallate (ECG) by two-step chromatography. In the first-step, four different macroporous absorption resins were compared by dynamic desorption, of which only AB-8 resin resulted in enriched fractions for EGCG and ECG. Their purity was 53.69 %, and 65.77 %, with recovery rates of 88.05 %, and 83.46 %, respectively. For the second-step, The recovery rates of 85.36 % and 86.09 % for EGCG and ECG were obtained respectively by a novel stationary phase of β-CD bonded agar gel. The overall recovery efficiency of the complete procedure was 75.16 % for EGCG and 71.85 % for ECG, respectively, and the purity of the obtained preparations reached 97.63 % for EGCG and 98.09 % for ECG. The chromatographic behavior of β-cyclodextrin bonded agar gel was studied with elution by acetonitrile, which indicated that both hydrophilic and hydrophobic interactions between the polyphenols and the solid phase occurred.

“…Palm oil sucrose esters (PSE) was separated into sucrose monoesters (PSME), diesters (PSDE), and polyesters (PSPE) using a high‐speed countercurrent chromatograph (HSCCC) equipped with three columns connected in series with a total capacity of 15 L . The columns were made by winding 38 m of polytetrafluoroethylene tubing (i.d.…”

Section: Methodsmentioning

confidence: 99%

Sucrose esters improve the colloidal stability of nanoethosomal suspensions of (−)‐epigallocatechin gallate for enhancing the effectiveness against UVB‐induced skin damage

Yang

et al. 2016

J Biomed Mater Res

Self Cite

Nanoethosomal suspensions, composed of phospholipids, ethanol, and water, are novel lipid carriers. These suspensions have been reported to enhance the permeation of drugs into the skin as a result of the interdigitation effect of ethanol on the lipid bilayer of liposomes and by increasing the fluidity of lipids in the stratum corneum. The physical stability of the nanoethosomal suspension is still a critical research problem until now. This study investigated the commercial palm sucrose esters to improve the colloidal stability of nanoethosomal suspensions. The results indicated that palm sucrose esters (PSE) were effective for stabilizing nanoethosomal suspension of (-)-epigallocatechin gallate (EGCG) from green tea. A PSE concentration of 0.15% was optimal for a nanoethosomal suspension which gave mean diameter 75.5 ± 3.5 nm, zeta potential -30.8 ± 3.2 mV and polydispersity index 0.207 ± 0.017. Moreover, the effectiveness of stabilization was influenced by the degree of esterification of the sucrose esters: the sucrose polyesters could prolong the stability of nanoethosomes loaded with EGCG to a year, but the sucrose monoesters only provided less than 6 months of stabilization. EGCG nanoethosomal suspension stabilized by sucrose polyesters shows better inhibition effectiveness against UVB-induced skin damage than native EGCG. The nanoethosomal suspension has the potential for its utilization as skin care and other products. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2416-2425, 2017.