title: Rapid quantitative enrichment of carnosic acid from rosemary (Rosmarinus officinalis L.) by isoelectric focused adsorptive bubble chromatography.
abstract: For the first time, the potent but unstable antioxidative diterpene carnosic acid could be enriched from an aqueous extract of rosemary (Rosmarinus officinalis L.) by isoelectric focused adsorptive bubble chromatography. Enrichment of carnosic acid in the foam was influenced by the pH value and the flow rate of the foam-forming gas. Efficiency was highest with diluted samples at pH 4. Under these conditions, the conversion of carnosic acid to carnosol was negligible. Transfer of carnosic acid to the foam from a standard solution in the presence of saponin as surfactive substance was similar to that from the aqueous rosemary extract.
authors.affiliation: Department of Chemical Technical Analysis and Chemical Food Technology, Technical University of Munich, Weihenstephaner Steig 23, D-85350 Freising Weihenstephan, Germany.
authors.forename: Marlène
authors.initials: M
authors.lastname: Backleh
authors.forename: Günther
authors.initials: G
authors.lastname: Leupold
authors.forename: Harun
authors.initials: H
authors.lastname: Parlar
mesh_terms: D045784:Abietanes; D000975:Antioxidants / Q000302:isolation & purification*; D002845:Chromatography / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D004224:Diterpenes / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D007525:Isoelectric Focusing / Q000379:methods*; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification*; D027542:Rosmarinus / Q000737:chemistry*; D012503:Saponins; D012996:Solutions; D014867:Water
chemical_list: D045784:Abietanes; D000975:Antioxidants; D004224:Diterpenes; D010936:Plant Extracts; D012503:Saponins; D012996:Solutions; D014867:Water; C018381:salvin