Sung Hum Yeon1, Je-Seung Jeon2, Key An Um3, Chul Young Kim2, Young-Joon Ahn1. 1. School of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea. 2. College of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan, Republic of Korea. 3. R&D Centre, Huons Co. Ltd, Ansan, Republic of Korea.
Abstract
INTRODUCTION: Secologanic acid, a major secoiridoid in the flower buds of Lonicera japonica, is a fragile, highly polar compound that readily changes to epivogeloside or vogeloside after being dissolved in methanol. Thus, it is very difficult to obtain secologanic acid on a large-scale. OBJECTIVE: To develop a centrifugal partition chromatography (CPC) method for large-scale purification of secologanic acid with high purity from the flower buds of L. japonica. METHODS: After fractionation with Diaion HP-20 macroporous resin, 30% methanol eluent was purified by CPC with a ternary biphasic solvent system with ethyl acetate/isopropanol/water (6:4:10, v/v/v). CPC was performed separately twice with the same solvent system, first in descending mode and second in ascending mode. RESULTS: After the first CPC operation, a secologanic acid enriched fraction (586 mg) was obtained from 3 g of crude extract, and secologanic acid (206 mg) was isolated with a purity over 93% in the subsequent ascending mode with the same solvent system from a 586 mg enriched fraction. In addition, it was confirmed that epivogeloside and vogeloside were reversely converted to secologanic acid in an aqueous acidic solution. CONCLUSION: These results demonstrate that CPC is a simple, effective, and rapid method for the purification of secologanic acid in the flower buds of L. japonica.
INTRODUCTION:Secologanic acid, a major secoiridoid in the flower buds of Lonicera japonica, is a fragile, highly polar compound that readily changes to epivogeloside or vogeloside after being dissolved in methanol. Thus, it is very difficult to obtain secologanic acid on a large-scale. OBJECTIVE: To develop a centrifugal partition chromatography (CPC) method for large-scale purification of secologanic acid with high purity from the flower buds of L. japonica. METHODS: After fractionation with Diaion HP-20 macroporous resin, 30% methanol eluent was purified by CPC with a ternary biphasic solvent system with ethyl acetate/isopropanol/water (6:4:10, v/v/v). CPC was performed separately twice with the same solvent system, first in descending mode and second in ascending mode. RESULTS: After the first CPC operation, a secologanic acid enriched fraction (586 mg) was obtained from 3 g of crude extract, and secologanic acid (206 mg) was isolated with a purity over 93% in the subsequent ascending mode with the same solvent system from a 586 mg enriched fraction. In addition, it was confirmed that epivogeloside and vogeloside were reversely converted to secologanic acid in an aqueous acidic solution. CONCLUSION: These results demonstrate that CPC is a simple, effective, and rapid method for the purification of secologanic acid in the flower buds of L. japonica.