Okra has three potential α-amylase inhibitors. - GreenMedInfo Summary

In this study, an on-line two-dimensional high-speed counter-current chromatography system based on a six-port valve was developed. Target-guided by ultrafiltration with high-performance liquid chromatography, the one-step isolation of three potentialα-amylase inhibitors from Abelmoschus esculentus (L).Moench was achieved by employing the developed orthogonal system and extrusion elution mode. The purities of three potential α-amylase inhibitors were all over 95% as determined by high-performance liquid chromatography. Furthermore, UV, mass spectrometry and (1) H NMR spectroscopy were applied to the structural identification of the isolated three target compounds, their structures were assigned as quercetin-3-O-sophoroside (i), 5,7,3',4'-tetrahydroxy flavonol-3-O-[β-d-rhamnopyranosil-(1→2)]-β-d-glucopyranoside (ii ) and isoquercitrin(iii), respectively. The Results demonstrated that the proposed method was highly efficient to screen and isolate enzyme inhibitors from complex natural products extracts, and on-line two-dimensional high-speed counter-current chromatography can effectively increase the peak resolution of target compounds.