title: A novel reductive amination method with isotopic formaldehydes for the preparation of internal standard and standards for determining organosulfur compounds in garlic.
abstract: Garlic (Allium sativum) is a long-cultivated plant that is widely utilized in cooking and has been employed as a medicine for over 4000 years. In this study, we fabricated standards and internal standards (ISs) for absolute quantification via reductive amination with isotopic formaldehydes. Garlic has four abundant organosulfur compounds (OSCs): S-allylcysteine, S-allylcysteinine sulfoxide, S-methylcysteine, and S-ethylcysteine are abundant in garlic. OSCs with primary amine groups were reacted with isotopic formaldehydes to synthesize ISs and standards. Cooked and uncooked garlic samples were compared, and we utilized tandem mass spectrometry equipped with a selective reaction monitoring technique to absolutely quantify the four organosulfur compounds.
authors.affiliation: Division of Urology, Ten Chan General Hospital, Taoyuan, Taiwan.
authors.forename: De-Cheng
authors.initials: DC
authors.lastname: Tsai
authors.affiliation: Department of Biotechnology, College of Life Science, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Meng-Chieh
authors.initials: MC
authors.lastname: Liu
authors.affiliation: Department of Biotechnology, Fooyin University, Kaohsiung, Taiwan.
authors.forename: Yi-Reng
authors.initials: YR
authors.lastname: Lin
authors.affiliation: Department of Biotechnology, College of Life Science, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Mei-Fang
authors.initials: MF
authors.lastname: Huang
authors.affiliation: Department of Biotechnology, College of Life Science, Kaohsiung Medical University, Kaohsiung, Taiwan; Institute of Biomedical Science, National Sun Yat-Sen University, Kaohsiung, Taiwan; Center for Research, Resources and Development, Kaohsiung Medical University, Kaohsiung, Taiwan. Electronic address: liang0615@kmu.edu.tw.
authors.forename: Shih-Shin
authors.initials: SS
authors.lastname: Liang
mesh_terms: D000586:Amination; D003545:Cysteine / Q000031:analogs & derivatives* / Q000032:analysis; D005557:Formaldehyde / Q000737:chemistry*; D005737:Garlic / Q000737:chemistry*; D010936:Plant Extracts / Q000032:analysis; D012015:Reference Standards; D013454:Sulfoxides / Q000032:analysis*; D053719:Tandem Mass Spectrometry
chemical_list: D010936:Plant Extracts; D013454:Sulfoxides; D005557:Formaldehyde; C065299:S-allylcysteine; C008425:S-methylcysteine; C026826:S-ethylcysteine; D003545:Cysteine
keywords: Organosulfur compounds (OSCs); Reductive amination; S-allylcysteine (SAC); S-allylcysteinine sulfoxide (alliin); S-ethylcysteine (SEC); S-methylcysteine (SMC)