title: HPLC Separation of Sulforaphane Enantiomers in Broccoli and Its Sprouts by Transformation into Diastereoisomers Using Derivatization with (S)-Leucine.
abstract: Racemic sulforaphane, which was derivatized with (S)-leucine (l-leucine), was resolved by reversed phase HPLC with UV detection. The optimum mobile phase conditions were found to be 10 mM citric acid (pH 2.8) containing 22% methanol at 35 °C using detection at 254 nm. Sulforaphane enantiomers in florets and stems of five brands of broccoli and leaves and stems of three brands of broccoli sprouts were analyzed by the proposed HPLC method. Both sulforaphane enantiomers were detected in all of the samples. The S/R ratios of sulforaphane in broccoli samples were 1.5-2.6/97.4-98.5% for florets and 5.0-12.1/87.9-95.0% for stems. The S/R ratios in broccoli sprout samples were higher than those in broccoli samples and were found to be 8.3-19.7/80.3-91.7% for leaves and 37.0-41.8/58.2-63.0% for stems. (S)-Sulforaphane detected in the broccoli and its sprout samples was positively identified by separately using an HPLC with a chiral column (Chiralpak AD-RH) and mass spectrometry.
authors.affiliation: School of Science, Tokai University , 4-1-1 Kitakaname, Hiratsuka, Kanagawa 259-1292, Japan.
authors.forename: Makiko
authors.initials: M
authors.lastname: Okada
authors.affiliation: Department of Biological Chemistry, College of Bioscience and Biotechnology, Chubu University , 1200 Matsumoto-cho, Kasugai-shi, Aichi 487-8501, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Yamamoto
authors.affiliation: Graduate School of Science and Engineering, University of Toyama , 3190 Gofuku, Toyama 930-8555, Japan.
authors.forename: Sen-Ichi
authors.initials: SI
authors.lastname: Aizawa
authors.affiliation: School of Pharmacy, Kinki University , 3-4-1 Kowakae, Higashi-Osaka 577-8502, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Taga
authors.affiliation: GL Sciences Inc. , 30F, Tokyo Square Tower, 22-1 Nishishinjuku 6-chome, Shinjuku-ku, Tokyo 163-1130, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Terashima
authors.affiliation: School of Science, Tokai University , 4-1-1 Kitakaname, Hiratsuka, Kanagawa 259-1292, Japan.
authors.forename: Shuji
authors.identifier: http://orcid.org/0000-0003-2883-0340
authors.initials: S
authors.lastname: Kodama
mesh_terms: D001937:Brassica / Q000737:chemistry* / Q000254:growth & development; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D017879:Isothiocyanates / Q000737:chemistry* / Q000302:isolation & purification; D007930:Leucine / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry / Q000254:growth & development; D018547:Plant Stems / Q000737:chemistry / Q000254:growth & development; D036226:Seedlings / Q000737:chemistry / Q000254:growth & development; D013237:Stereoisomerism; D013454:Sulfoxides
chemical_list: D017879:Isothiocyanates; D013454:Sulfoxides; C016766:sulforaphane; D007930:Leucine
keywords: HPLC; broccoli; diastereomer; enantioseparation; sulforaphane