title: Preparation of a Ammonia-Treated Lac Dye and Structure Elucidation of Its Main Component.
abstract: Lac dye and cochineal extract contain laccaic acids and carminic acid as the main pigments, respectively. Both laccaic acids and carminic acid are anthraquinone derivatives. 4-Aminocarminic acid (acid-stable carmine), an illegal colorant, has been detected in several processed foods. 4-Aminocarminic acid is obtained by heating cochineal extract (carminic acid) in ammonia solution. We attempted to prepare ammonia-treated lac dye and to identify the structures of the main pigment components. Ammonia-treated lac dye showed acid stability similar to that of 4-aminocarminic acid. The structures of the main pigments in ammonia-treated lac dye were analyzed using LC/MS. One of the main pigments was isolated and identified as 4-aminolaccaic acid C using various NMR techniques, including 2D-INADEQUATE. These results indicated that ammonia-treatment of lac dye results in the generation of 4-aminolaccaic acids.
authors.affiliation: National Institute of Health Sciences.
authors.forename: Yuzo
authors.initials: Y
authors.lastname: Nishizaki
authors.forename: Kyoko
authors.initials: K
authors.lastname: Ishizuki
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Akiyama
authors.forename: Atsuko
authors.initials: A
authors.lastname: Tada
authors.forename: Naoki
authors.initials: N
authors.lastname: Sugimoto
authors.forename: Kyoko
authors.initials: K
authors.lastname: Sato
mesh_terms: D000641:Ammonia; D001391:Azo Compounds / Q000032:analysis* / Q000737:chemistry* / Q000302:isolation & purification; D002119:Calcium Carbonate; D002329:Carmine / Q000032:analysis / Q000302:isolation & purification; D002853:Chromatography, Liquid; D002951:Citrates; D004338:Drug Combinations; D004355:Drug Stability; D005504:Food Analysis; D005505:Food Coloring Agents / Q000032:analysis* / Q000737:chemistry* / Q000302:isolation & purification; D005506:Food Contamination / Q000032:analysis*; D008277:Magnesium Oxide; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D013058:Mass Spectrometry
chemical_list: D001391:Azo Compounds; D002951:Citrates; D004338:Drug Combinations; D005505:Food Coloring Agents; C050615:Suby's G solution; C009765:lac dye; D008277:Magnesium Oxide; D000641:Ammonia; D002329:Carmine; D002119:Calcium Carbonate