title: The effect of O-methylated flavonoids and other co-metabolites on the crystallization and purification of artemisinin.
abstract: Methoxylated flavonoids casticin, artemetin and retusin were identified as putative causative factors for low crystallization yields of artemisinin from extracts. Comparative profiling of biomass grown in different countries found elevated levels (∼60% higher) of artemetin in the East African biomass, which also demonstrates poor crystallization yields. The single compound and the combined doping experiments at 0, 25 and 50 μg mL⁻¹ doping levels showed that artemetin (50 μg mL⁻¹) caused a reduction in the amount of artemisinin crystallized by ca. 60%. A combination of the three flavonoids at 50 μg mL⁻¹ almost completely inhibited crystallization, reducing the yield by 98%. Treatment of extracts by adsorbents efficiently resolves the problem of low crystallization yield.
authors: School of Engineering, University of Warwick, Coventry CV4 7AL, UK; School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK; Department of Chemical Engineering and Biotechnology, University of Cambridge, CB2 3RA, UK.
authors: John O
authors: JO
authors: Suberu
authors: Institute of Technical Thermodynamics, RWTH Aachen, Germany.
authors: Peyman
authors: P
authors: Yamin
authors: Institute of Technical Thermodynamics, RWTH Aachen, Germany.
authors: Kai
authors: K
authors: Leonhard
authors: Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK.
authors: Lijiang
authors: L
authors: Song
authors: Centre de Recherches en Analyses Physico-Chimiques (CRAPC), Alger, Algeria.
authors: Smain
authors: S
authors: Chemat
authors: Sensapharm Ltd., Business and Innovation Centre, Sunderland SR5 2TA, UK.
authors: Neil
authors: N
authors: Sullivan
authors: School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK. Electronic address: guy.barker@warwick.ac.uk.
authors: Guy
authors: G
authors: Barker
authors: Department of Chemical Engineering and Biotechnology, University of Cambridge, CB2 3RA, UK. Electronic address: aal35@cam.ac.uk.
authors: Alexei A
authors: AA
authors: Lapkin
mesh_terms: D000327:Adsorption; D031172:Artemisia annua / Q000737:chemistry; D037621:Artemisinins / Q000032:analysis / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D005419:Flavonoids / Q000032:analysis / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry; D014885:Waxes / Q000032:analysis / Q000737:chemistry
chemical_list: D037621:Artemisinins; D005419:Flavonoids; D010936:Plant Extracts; D014885:Waxes; C031327:artemisinin
keywords: Artemisinin; Biopharmaceuticals; Bioseparations; Crystallization