title: A derivatization method for the simultaneous detection of glucosinolates and isothiocyanates in biological samples.
abstract: Various analytical methods have been established to quantify isothiocyanates (ITCs) that derive from glucosinolate hydrolysis. However, to date there is no valid method applicable to pharmacokinetic studies that detects both glucosinolates and ITCs. A specific derivatization procedure was developed for the determination of ITCs based on the formation of a stable N-(tert-butoxycarbonyl)-L-cysteine methyl ester derivative, which can be measured by high-performance liquid chromatography with ultraviolet detection after extraction with ethylacetate. The novel method, which is also applicable to the indirect determination of glucosinolates after their hydrolysis by myrosinase, was established for the simultaneous determination of glucoraphanin and sulforaphane. By derivatization, the sensitivity of ITC detection was increased 2.5-fold. Analytical recoveries from urine and plasma were greater than 75% and from feces were approximately 50%. The method showed intra- and interday variations of less than 11 and 13%, respectively. Applicability of the method was demonstrated in mice that received various doses of glucoraphanin or that were fed a glucoraphanin-rich diet. Besides glucoraphanin and sulforaphane, glucoerucin and erucin were detected in urine and feces of mice. The novel method provides an essential tool for the analysis of bioactive glucosinolates and their hydrolysis products and, thus, will contribute to the elucidation of their bioavailability.
authors.affiliation: Department of Gastrointestinal Microbiology, German Institute of Human Nutrition Potsdam-Rehbruecke, 14558 Nuthetal, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Budnowski
authors.forename: Franziska S
authors.initials: FS
authors.lastname: Hanschen
authors.forename: Carsten
authors.initials: C
authors.lastname: Lehmann
authors.forename: Michael
authors.initials: M
authors.lastname: Haack
authors.forename: Regina
authors.initials: R
authors.lastname: Brigelius-Flohé
authors.forename: Lothar W
authors.initials: LW
authors.lastname: Kroh
authors.forename: Michael
authors.initials: M
authors.lastname: Blaut
authors.forename: Sascha
authors.initials: S
authors.lastname: Rohn
authors.forename: Laura
authors.initials: L
authors.lastname: Hanske
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003553:Cystine / Q000031:analogs & derivatives; D005243:Feces / Q000737:chemistry; D005947:Glucose / Q000031:analogs & derivatives / Q000032:analysis; D005961:Glucosinolates / Q000032:analysis* / Q000097:blood / Q000652:urine; D006868:Hydrolysis; D007096:Imidoesters / Q000032:analysis*; D017879:Isothiocyanates / Q000032:analysis* / Q000097:blood / Q000652:urine; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010091:Oximes; D013440:Sulfides / Q000032:analysis / Q000652:urine; D013454:Sulfoxides; D013861:Thiocyanates / Q000032:analysis / Q000652:urine
chemical_list: D005961:Glucosinolates; D007096:Imidoesters; D017879:Isothiocyanates; D010091:Oximes; D013440:Sulfides; D013454:Sulfoxides; D013861:Thiocyanates; C119493:glucoerucin; D003553:Cystine; C073539:erucin; C016766:sulforaphane; D005947:Glucose; C119494:glucoraphanin
keywords: Derivatization; Glucoraphanin; Glucosinolate; Isothiocyanate; N-(tert-Butoxycarbonyl)-l-cysteine methyl ester; Sulforaphane