title: Solid-phase extraction for purification of alkannin/shikonin samples and isolation of monomeric and dimeric fractions.
abstract: Isohexenylnaphthazarins (IHN), commonly known as alkannins and shikonins (A/S), are potent pharmaceutical substances with a wide spectrum of wound healing, antimicrobial, anti-inflammatory, and antitumor activity. Purification of A/S is crucial for their use in pharmaceuticals and for biological experimentation. Dimeric and oligomeric A/S derivatives co-exist with the active monomeric ones in most of the samples produced either by (semi)-synthesis or biotechnologically or isolated from natural products. Oligomeric A/S derivatives have not been studied for biological activity hitherto and a method to isolate them is essential.In the present study, solid-phase extraction (SPE) was applied for purification of commercial samples and isolation of monomeric and oligomeric A/S fractions, testing several stationary phases. Sephadex LH-20 cartridges achieved efficient purification for commercial samples containing both monomeric and dimeric A/S derivatives and also separation and isolation of both pure monomeric and dimeric A/S fractions for biological experiments. A high-performance liquid chromatography-diode array detection method was applied for detection, identification and quantification of monomeric and oligomeric shikonin fractions.
authors.affiliation: Laboratory of Analytical Chemistry, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 541 24, Greece.
authors.forename: E
authors.initials: E
authors.lastname: Noula
authors.forename: V F
authors.initials: VF
authors.lastname: Samanidou
authors.forename: A N
authors.initials: AN
authors.lastname: Assimopoulou
authors.forename: V P
authors.initials: VP
authors.lastname: Papageorgiou
authors.forename: I N
authors.initials: IN
authors.lastname: Papadoyannis
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal; D002853:Chromatography, Liquid / Q000295:instrumentation; D003911:Dextrans; D009285:Naphthoquinones / Q000302:isolation & purification*; D052616:Solid Phase Extraction / Q000379:methods*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D003911:Dextrans; D009285:Naphthoquinones; C018204:alkannin; C016101:shikonin; C025614:sephadex