Isolation and purification of flavonoids from <i>Euonymus alatus</i> by high‐speed countercurrent chromatography and neuroprotective effect of rhamnazin‐3‐O‐rutinoside in vitro

Cyperus rotundus L. has been extensively used in ancient medication for the treatment of different disorders worldwide, in which sesquiterpenes are the most representative components. In this study, sesquiterpenes were effectively purified by two-dimensional counter-current chromatography in combination with continuous injection and inner-recycling mode with a solvent system of nhexane/ethyl acetate/methanol/water (1:0.2:1:0.2, v/v/v/v). For one-dimension separation, continuous injection mode was used with three times injection and the inner-recycling mode was adopted for the separation of two mixtures for two-dimensional separation. Finally, four sesquiterpenoids, including scariodione (1), cyperenoic acid (2), scariodione (3), and α-cyperone (4), were obtained with purities over 98%. Mass spectrometry and nuclear magnetic resonance were applied to identify their structures. The results from the anti-inflammation effect with zebrafish demonstrated that cyperenoic acid exhibited stronger antiinflammation activity. Molecular docking results suggested that cyperenoic acid possessed lower binding energies -9.4545 kcal/mol with 1CX2 to form formed hydrogen bond interaction with ARG120. In general, all the obtained findings Article Related Abbreviations: HSCCC, high-speed counter-current chromatography; K D -value, partition coefficient.

Section: Resultsmentioning

confidence: 99%

An efficient high‐speed counter‐current chromatography method for the preparative separation of sesquiterpenoids from the rhizomes of Cyperus rotundus L. combined with evaluation of the anti‐inflammation activity in vitro and molecular docking

Pan

Zhang

Feng

et al. 2023

“…The K D‐ values ranging from 0.5 to 2.0 were reported to be suitable [23] while maintaining separation coefficient ( α ‐values) ( α = K 1 / K 2 , K 1 > K 2 ) higher than 1.5 [24]. K D ‐values higher than 2.0 would lead to a longer retention time, whereas K D ‐values smaller than 0.5 would result in poor separation.…”

Section: Resultsmentioning

confidence: 99%

An efficient high‐speed counter‐current chromatography method for the preparative separation of potential antioxidants from Paeonia lactiflora Pall. combination of in vitro evaluation and molecular docking

Sun

Chen

Yan

et al. 2022

Paeonia lactiflora Pall., one of the most famous classical herbal medicine, has been used to treat diseases for over 1200 years. In this research, the functional ingredients were purified by online‐switch two‐dimensional high‐speed counter‐current chromatography combined with inner‐recycling and continuous injection mode. The antioxidant activity was evaluated by investigating the 2,2′‐azobis (2‐amidinopropane) dihydrochloride‐induced oxidant damage in vitro and confirmed through molecular docking. n‐Butanol/ethyl acetate/water (2:3:5, v/v) solvent system was used for the first‐dimensional separation and optimized the sample loading. Two pure compounds and a polyphenol‐enriched fraction were separated. The polyphenol‐enriched fraction was separated with a solvent system n‐hexane/ethyl acetate/methanol/water (2:8:4:6, v/v) with continuous injection mode. Five compounds were successfully separated, including gallic acid (1), methyl gallate (2), albiflorin (3), paeoniflorin (4), and ethyl gallate (5). Their structures were identified by mass spectrometry and NMR spectroscopy. The results from the antioxidant effect showed that albiflorin had stronger antioxidant activity. Molecular docking results indicated that the affinity energy of the identified compounds ranged from ‐3.79 to ‐8.22 kcal/mol and albiflorin showed the lowest affinity energy. Overall, all those findings suggested that the strong antioxidant capacity of albiflorin can be potentially used for the treatment of diseases caused by oxidation.

“…The partition coefficient (K D ) of an effective solvent system typically lies in the range of 0.2−5, while the value of α exceeds 1.5 [22]. n-Hexane-ethyl acetate-methanolwater is a common solvent system covering a wide polarity range for HSCCC, and has been widely used for the separation and purification of constituents from herbal medicines [16,17]. In accordance with previous studies [23], a series of two-phase solvent systems composed of different ratios of n-hexane, ethyl acetate, methanol, and water was screened to measure the K-values of the major compounds.…”

Section: Selection Of the Two-phase Solvent Systemmentioning

confidence: 99%

“…However, separating the chemical components from complex extracts remains challenging, particularly for minor components. Being a supportfree liquid-liquid partition chromatographic technique, high-speed countercurrent chromatography (HSCCC) is characterized by high sample recovery and reproducibility, which enhances its efficiency toward the isolation of major compounds at high purities in a single step and greatly facilitates the enrichment of minor constituents [11][12][13][14][15][16][17]. However, for complex mixtures, it is extremely difficult to purify all target active compounds via a single-step separation process.…”

Section: Introductionmentioning

confidence: 99%

Preparative isolation of diterpenoids from Salvia bowleyana Dunn roots by high‐speed countercurrent chromatography combined with high‐performance liquid chromatography

Jiang

Chen

Yang

et al. 2022

The root of Salvia bowleyana Dunn (Lamiaceae) is used as a traditional Chinese medicine that has multiple therapeutic effects. In this study, an efficient strategy was developed to separate diterpenoid compounds, which are the main active ingredients in Salvia bowleyana Dunn roots, from complex crude extracts by high‐speed countercurrent chromatography combined with preparative high‐performance liquid chromatography. A two‐phase solvent system comprising n‐hexane–ethyl acetate–methanol–water (7:3:7:3, v/v/v/v) was selected for high‐speed countercurrent chromatographic separation. Three major diterpenoids, 6α‐hydroxysugiol (7), sugiol (8), and 6, 12‐dihydroxyabieta‐5,8,11,13‐tetraen‐7‐one (9) were obtained at purities of 98.9, 95.4, and 96.2%, respectively, and minor diterpenoids were enriched via one‐step separation. The enriched minor diterpenoids were further purified by continuous preparative high‐performance liquid chromatography to yield two new norabietanoids (1, 6) and four known compounds (2–5). The structures of these new compounds were determined using NMR spectroscopy, high‐resolution electrospray ionization mass spectrometry, and electronic circular dichroism spectroscopy. The results suggest that high‐speed countercurrent chromatography combined with preparative high‐performance liquid chromatography efficiently isolates diterpenoids, including minor components, from complex natural products.