title: Thermolysis kinetics and thermal degradation compounds of alliin.
abstract: To investigate thermolysis kinetics and identify degradation compounds, alliin solutions were heated at 60, 80, and 89°C. The degradation compounds of alliin were identified by high performance liquid chromatography-mass spectrometry (HPLC-MS), tandem mass spectrometry (MS/MS) and ultra-pressure liquid chromatography-high resolution mass spectrometry (UPLC-HRMS). The results showed that the thermal degradation kinetic of alliin could be described by a first-order reaction and k=4.38×1017exp (-142494/RT), where k is the reaction rate constant, min-1; R is gas constant; T is the absolute temperature, K. Degraded compounds, including S-allyl-l-cysteine and ethers, such as allyl alanine disulfide, allyl alanine trisulfide, allyl alanine tetrasulfide, dialanine disulfide (cysteine), dialanine trisulfide and dialanine tetrasulfide, were identified by HPLC-MS, MS/MS and UPLC-HRMS. Allyl alanine tetrasulfide was identified for the first time in alliin. The results show that alliin is unstable and significant numbers of organosulfur compounds are generated under high temperature treatment.
authors.affiliation: Department of Food Science and Engineering, Jinan University, Guangzhou 510632, China.
authors.forename: Zixing
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Department of Food Science and Engineering, Jinan University, Guangzhou 510632, China.
authors.forename: MingJiao
authors.initials: M
authors.lastname: Xu
authors.affiliation: Department of Food Science and Engineering, Jinan University, Guangzhou 510632, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Food Science and Engineering, Jinan University, Guangzhou 510632, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Zhou
authors.affiliation: Department of Food Science and Engineering, Jinan University, Guangzhou 510632, China.
authors.forename: Lokyee
authors.initials: L
authors.lastname: Fan
authors.affiliation: Department of Food Science and Engineering, Jinan University, Guangzhou 510632, China. Electronic address: thxs@jnu.edu.cn.
authors.forename: Xuesong
authors.initials: X
authors.lastname: Huang
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D002853:Chromatography, Liquid / Q000379:methods; D003545:Cysteine / Q000031:analogs & derivatives* / Q000032:analysis / Q000493:pharmacokinetics; D006358:Hot Temperature / Q000009:adverse effects; D007700:Kinetics; D053719:Tandem Mass Spectrometry / Q000379:methods
chemical_list: C006453:alliin; C065299:S-allylcysteine; D003545:Cysteine
keywords: Alanine; Alliin; Arrhenius equation; Kinetics; Polysulfide ether; Thermal decomposition