title: Extraction and separation of lactate dehydrogenase inhibitors from Poria cocos (Schw.) Wolf based on a hyphenated technique and in vitro methods.
abstract: Stroke is one of the most common diseases worldwide. Lactate dehydrogenase inhibitors are widely used in the treatment of ischemic stroke, with natural products considered a promising source of lactate dehydrogenase inhibitors. In this study, ultrafiltration liquid chromatography coupled with mass spectrometry was used for the screening and identification of lactate dehydrogenase inhibitors from Poria cocos. Five lactate dehydrogenase inhibitors were selected: dehydropachymic acid, pachymic acid, dehydrotrametenolic acid, trametenolic acid, and eburicoic acid. The inhibitors were extracted and isolated with purities of 96.75, 98.15, 97.25, 95.46, and 94.88%, respectively, by using a new "hyphenated" strategy of microwave-assisted extraction coupled with counter-current chromatography and centrifugal partition chromatography by a two-phase solvent system of n-hexane/ethyl acetate/ethanol/water at the volume ratio 0.965:1.000:0.936:0.826 v/v/v/v. The bioactivity of the isolated compounds was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay in PC12 cells. The results also showed that the hyphenated technique of microwave-assisted extraction coupled with counter-current chromatography and centrifugal partition chromatography was an efficient method for the continuous extraction and online isolation of chemical constituents from medicinal herbs. Furthermore, the research route based on the activity screening, extraction, separation, and activity verification of the compounds offered advantages of efficiency, orientation, and objectivity.
authors.affiliation: Central Laboratory, Changchun Normal University, Changchun, China.|Changchun Center of Mass Spectrometry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, China.
authors.forename: Sainan
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Rehabilitation, Second Branch of the First Hospital of Jilin University, Changchun, China.
authors.forename: Jianxu
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Central Laboratory, Changchun Normal University, Changchun, China.
authors.forename: Senlin
authors.initials: S
authors.lastname: Li
authors.affiliation: Central Laboratory, Changchun Normal University, Changchun, China.
authors.forename: Chunming
authors.initials: C
authors.lastname: Liu
authors.affiliation: Changchun Center of Mass Spectrometry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, China.
authors.forename: Shu
authors.initials: S
authors.lastname: Liu
authors.affiliation: Changchun Center of Mass Spectrometry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, China.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D003377:Countercurrent Distribution; D004791:Enzyme Inhibitors / Q000302:isolation & purification*; D007770:L-Lactate Dehydrogenase / Q000037:antagonists & inhibitors*; D013058:Mass Spectrometry; D016716:PC12 Cells; D051381:Rats; D000070660:Wolfiporia / Q000737:chemistry*
chemical_list: D004791:Enzyme Inhibitors; D007770:L-Lactate Dehydrogenase
keywords: Poria cocos; combined chromatography; lactate dehydrogenase; microwave-assisted extraction; stroke