K淝界 8 2 000.10203040.50.60.7 水份活度 早餐谷物食品在45°℃C贮藏条件下硫胺素的 降解速率与体系中水分活度的关系
早餐谷物食品在45℃贮藏条件下硫胺素的 降解速率与体系中水分活度的关系
Degradation 两环间亚甲基易与强亲核试剂反应 与亚硝酸盐反应,使VB1失活 在碱性条件下易降解,其降解机制为:
➢ 两环间亚甲基易与强亲核试剂反应。 ➢ 与亚硝酸盐反应,使VB1失活. ➢ 在碱性条件下易降解,其降解机制为: Degradation
H,CS SCH CH2OH 加热 H cS. SCH NH CH,-CHOH H20 pH>5,加热 CH CH NH CH2-CH2OH 氧化 亚硫酸盐 CH2 sO3H nh CHo-CH.OH 硫胺素的降解
Function of thiamin Glycogen diglycerides Proteins TPLP CoA NAD PLP Glucose NADP THFA THFA B-12 N Fatty acids and B-12 CO2 TPP glycerol Amino acids Some component of dNA and RNA FAD PLP NAD yruvic acid CoA NADP NAD FAD NAD PLP LNAD Bi lotin CoA FAD B-12 Biotin Acetyl-CoA THFA Citric acid TPP cycle /NAD FAD CoA co. 12 o2 H2o Electron transport chain NAD FMN. FAD
Function of Thiamin
Coenzyme: Thiamin Pyrophosphate (TPP) Synthesis of neurotransmitter Hexose monophosphate shunt Removes co2 from some amino acids Convert pyruvate to acetyl-CoA COA NAD+ nadh+h+ Glucose Pyruvate Acetyl-COA Citric CO2 Acid cycle
Coenzyme: Thiamin Pyrophosphate (TPP) ◼ Synthesis of neurotransmitter ◼ Hexose monophosphate shunt ◼ Removes CO2 from some amino acids ◼ Convert pyruvate to acetyl-CoA CoA NAD+ NADH + H+ Glucose Pyruvate Acetyl-CoA Citric CO2 Acid Cycle