Preparative isolation and purification of antioxidative diarylheptanoid derivatives from Alnus japonica by high‐speed counter‐current chromatography

Abstract

This study employed the online HPLC-2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS)(+) bioassay to rapidly determine the antioxidant compounds occurring in the crude extract of Alnus japonica. The negative peaks of the ABTS(+) radical scavenging detection system, which indicated the presence of antioxidant activity, were monitored by measuring the decrease in absorbance at 734 nm. The ABTS(+)-based antioxidant activity profile showed that three negative peaks exhibited antioxidant activity. High-speed counter-current chromatography (HSCCC) was used for preparative scale separation of the three active peaks from the extract. The purity of the isolated compounds was analyzed by HPLC and their structures were identified by (1)H- and (13)C-nuclear magnetic resonance spectrometry (NMR), heteronuclear multiple bond correlation (HMBC), and heteronuclear single quantum correlation (HSQC). Two solvent systems composed of n-hexane/ethylacetate/methanol/water (4:6:4:6, v/v) and of ethyl acetate/methanol/water (1:0.1:1, v/v) were performed in high-speed counter-current chromatography. Consequently, a total of 527 mg of hirsutanonol 5-O-β-D-glucopyranoside, 80.04 mg of 3-deoxohirsutenonol 5-O-β-D-glucopyranoside, and 91.0 mg of hirsutenone were obtained with purity of 94.7, 90.5, and 98.6%, respectively.

Characterization of diarylheptanoids: An emerging class of bioactive natural products

“…HSCCC was used for preparative scale separation of the active constituents from the ethanol extract of Alnus japonica stems. HSCCC separation of the ethyl acetate fraction from the crude extract yielded hirsutanonol-5-O-␤-d-glucopyranoside, 3-deoxohirsutanonol-5-O-␤-d-glucopyranoside, and hirsutenone with recoveries of 95.4%, 97.0%, and 93.7% (purities: 94.7%, 90.5%, and 98.6%), respectively [88].…”

The Genus Alnus, A Comprehensive Outline of Its Chemical Constituents and Biological Activities

“…It is worth mentioning that compounds 48 and 9 showed stronger antioxidative activities than the well-known antioxidant curcumin [ 90 ]. Furthermore, many other compounds also exhibited remarkable free-radical-scavenging capacity; e.g., diarylheptanoids 4 , 14 , 36 , 49 , polyphenols 109 , 111 , 115 , 134 and flavones 144 , 157 [ 15 , 38 , 98 , 102 ]. As we all know, polyphenols are natural antioxidants, and the protection against oxidative damage is due to their antioxidant effects.…”

“…japonica , a famous medical herb in China, Japan and Korea as well as a functional food consumed in health drinks, contains abundant diarylheptanoid derivatives, in addition to methylated and acylated diarylheptanoids and diarylheptanoid glycosides [ 12 , 13 , 14 ]. It has been known to exert antioxidative, anti-inflammatory, anticancer and hepatoprotective effects and its antioxidative properties are presumed to contribute to its hepatoprotective activity in certain situations [ 15 ]. Diarylheptanoids with strong antioxidative activity isolated from A .…”

Preparative Purification of Anti-Proliferative Diarylheptanoids from Betula platyphylla by High-Speed Counter-Current Chromatography

“…[20]. To the best of our knowledge, there are few reports on the preparative separation of diarylheptanoids from plant extracts using HSCCC to date [21,22]. The present paper describes the successful preparative separation and purification of the two diarylheptanoids aceroside VIII ( 1 ) and platyphylloside ( 2 ) (Figure 1) from a crude sample of B. platyphylla using HSCCC in stepwise elution mode.…”