Target-guided isolation of polar antioxidants from Abelmoschus esculentus (L). Moench by high-speed counter-current chromatography method coupled with wavelength switching and extrusion elution mode

• Published in: Journal of separation science 2016-10, Vol.39 (20), p.3983-3989
• Main Authors: Wang, Ranhao, Liu, Qi, Wu, Zhiliang, Wang, Meiling, Chen, Xiaoqing
• Format: Article
• Language: English
• Subjects: Abelmoschus - chemistry; Abelmoschus esculentus (L).Moench; Antioxidants; Antioxidants - isolation & purification; Chromatography; Chromatography, High Pressure Liquid; Countercurrent Distribution; Elution; Extrusion; Extrusion elution mode; High speed; High-speed counter-current chromatography; Plant Extracts - chemistry; Separation; Switching; Wavelength switching; Wavelengths
• ISSN: 1615-9306; 1615-9314
• DOI: 10.1002/jssc.201600617

An off‐line two‐dimensional high‐speed counter‐current chromatography strategy combined with the wavelength switching technique and extrusion elution mode was successfully developed and applied to the isolation of polar antioxidants from Abelmoschus esculentus (L).Moench. Target‐guided by the result of 2,2‐diphenyl‐1‐picrylhydrazyl screening assay, four antioxidants were obtained with purities over 90% through orthogonal high‐speed counter‐current chromatography separation. UV spectroscopy, mass spectrometry and 1H NMR spectroscopy were employed to identify their structures, which were assigned as l‐tryptophan, quercetin‐3‐O‐sophoroside, 5,7,3′,4′‐tetrahydroxyflavonol‐3‐O‐[β‐d‐rhamnopyranosil‐(1→2)]‐β‐d‐glucopyranoside, and quercetin‐3‐O‐glucoside. Each monomer exhibited significant antioxidant activity. The results demonstrated that proposed method could be an effective approach to isolate bioactive compounds from complex natural products.