title: Rapid identification of α-glucosidase inhibitors from Phlomis tuberosa by Sepbox chromatography and thin-layer chromatography bioautography.
abstract: Alpha-glucosidase inhibitors currently form an important basis for developing novel drugs for diabetes treatment. In our preliminary tests, the ethyl acetate fraction of Phlomis tuberosa extracts showed significant α-glucosidase inhibitory activity (IC₅₀ = 100 μg/mL). In the present study, a combined method using Sepbox chromatography and thin-layer chromatography (TLC) bioautography was developed to probe α-glucosidase inhibitors further. The ethyl acetate fraction of P. tuberosa extracts was separated into 150 individual subfractions within 20 h using Sepbox chromatography. Then, under the guidance of TLC bioautography, 20 compounds were successfully isolated from these fractions, including four new diterpenoids [14-hydroxyabieta-8,11,13-triene-11-carbaldehyde-18-oic-12-carboxy-13-(1-hydroxy-1-methylethyl)-lactone (1), 14-hydroxyabieta-8,11,13-triene-17-oic-12-carboxy-13-(1-hydroxy-1-methylethyl)-lactone (2), 14,16-dihydroxyabieta-8,11,13-triene-15,17-dioic acid (3), and phlomisol (15,16-eposy-8,13(16),14-labdatrien-19-ol) (4)], and 16 known compounds. Activity estimation indicated that 15 compounds showed more potent α-glucosidase inhibitory effects (with IC50 values in the range 0.067-1.203 mM) than the positive control, acarbose (IC50 = 3.72 ± 0.113 mM). This is the first report of separation of α-glucosidase inhibitors from P. tuberosa.
authors: The MOE Key Laboratory of Standardization of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
authors: Yingbo
authors: Y
authors: Yang
authors: The MOE Key Laboratory of Standardization of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
authors: Lihua
authors: L
authors: Gu
authors: The MOE Key Laboratory of Standardization of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, China; Department of Pharmacy, Changzheng Hospital, Second Military Medical University, Shanghai, China.
authors: Ying
authors: Y
authors: Xiao
authors: The MOE Key Laboratory of Standardization of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, China; Shanghai R & D Center for Standardization of Chinese Medicines, Shanghai, China.
authors: Qing
authors: Q
authors: Liu
authors: The MOE Key Laboratory of Standardization of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
authors: Haijun
authors: H
authors: Hu
authors: The MOE Key Laboratory of Standardization of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, China; Shanghai R & D Center for Standardization of Chinese Medicines, Shanghai, China.
authors: Zhengtao
authors: Z
authors: Wang
authors: The MOE Key Laboratory of Standardization of Chinese Medicines, Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
authors: Kaixian
authors: K
authors: Chen
mesh_terms: D002855:Chromatography, Thin Layer; D065089:Glycoside Hydrolase Inhibitors / Q000737:chemistry* / Q000302:isolation & purification*; D031345:Phlomis / Q000737:chemistry*; D000520:alpha-Glucosidases / Q000737:chemistry*
chemical_list: D065089:Glycoside Hydrolase Inhibitors; D000520:alpha-Glucosidases