title: Spectrophotometric determination of lantadene A, 22 beta-angeloyloxy-3-oxoolean-12-en-28-oic acid.
abstract: The formation of a blue chromogen between sodium borohydride-treated lantadene A (22 beta-angeloyloxy-3-oxoolean-12-en-28-oic acid) and acetic anhydride-sulfuric acid (9:1) formed the basis of a spectrophotometric method for its quantitation. The chromogen had a broad absorption maximum (lambda max) at 630-645 nm. The optimum amount of sodium borohydride for lantadene A reduction was 1 mg/mg lantadene A in methanolic solution. The chromogen was stable for 5, 7, and 26 min after reaction at 25, 18, and 0 degree C, respectively. The method is convenient, sensitive, and reproducible. The amount of lantadene A in the leaves of Lantana camara collected in the month of May quantitated by the present method was found to be 13.6 mg/g dry weight of the leaves.
mesh_terms: D009828:Oleanolic Acid / Q000031:analogs & derivatives / Q000032:analysis*; D010084:Oxidation-Reduction; D010936:Plant Extracts / Q000032:analysis; D012502:Sapogenins / Q000032:analysis*; D013053:Spectrophotometry / Q000379:methods; D014118:Toxins, Biological / Q000032:analysis
chemical_list: D010936:Plant Extracts; D012502:Sapogenins; D014118:Toxins, Biological; D009828:Oleanolic Acid; C019074:rehmannic acid