Bioactivity-Guided Separation of Potential D₂ Dopamine Receptor Antagonists from Aurantii Fructus based on Molecular Docking Combined with High-Speed Counter-Current Chromatography.
Ying-Jie HeShihao ZhuChangqiao WuYing LuQi TangPublished in: Molecules (Basel, Switzerland) (2018)
The typical compounds of Aurantii fructus (AF) reported in previous research were screened for their high antagonistic ability on the D₂ dopamine receptor (D₂R) in silico, and then bioactivity-guided separation was undertaken on the potential D₂R antagonists from AF using high-speed counter-current chromatography (HSCCC). Three flavanones, two polymethoxyflavonoids, and three coumarins were effectively isolated from ethanol extracts of Aurantii fructus (AF) by the use of a two-step HSCCC method, and their chemical structures were identified by mass spectrometry, ¹H-NMR, and 13C-NMR and compared with published data. Firstly, crude extract of 70% ethanol eluent (150 mg) was isolated by HSCCC using an n-hexane-ethyl acetate-n-butanol-methanol-0.05% acetic acid (1:3:1.8:1:5, v/v/v/v/v) solvent system, and compounds 1 (naringin, 28 mg), 2 (neohesperidin, 13 mg), 3 (meranzin, 5 mg) and 4 (poncirin, 3 mg) were successfully isolated with 98.5%, 95.1%, 97.7%, and 92.4% purity, respectively. Then, the crude extract of 95% ethanol eluent (120 mg) was isolated by n-hexane-n-butanol-ethanol (methanol)-0.05% acetic acid (2:0.6:1:3, v/v/v/v) solvent system and compounds 3 (meranzin, 3 mg), 5 (meranzin hydrate, 4 mg), 6 (isomeranzin, 6 mg), 7 (nobiletin, 10 mg), and 8 (tangeretin, 7 mg) were successfully isolated with 95.8%, 98.5%, 95.1%, 92.4%, and 97.7% purity, respectively. Naringenin, a parent structure of naringin with the excellent binding score of -9.3 kcal/mol, was completely in conjunction with the active site of D₂R, indicating that it is critical for the treatment of gastrointestinal dysfunction. The results indicated that the bioactivity-guided method is practical for the effective separation of active compounds from natural resources.
Keyphrases
- high speed
- mass spectrometry
- molecular docking
- liquid chromatography
- high resolution
- atomic force microscopy
- oxidative stress
- atrial fibrillation
- magnetic resonance
- machine learning
- systematic review
- randomized controlled trial
- molecular dynamics simulations
- climate change
- transcription factor
- high performance liquid chromatography
- deep learning
- ms ms
- big data