Zhang Han, Cui Heping, Xia Xue, Zhang Foxin, Hayat Khizar, Zhang Xiaoming, Ho Chi-Tang
State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, Jiangsu, P. R. China.
Anhui QiangWang Flavouring Food Co. Ltd., Fuyang 236500, Anhui, P. R. China.
J Agric Food Chem. 2023 Apr 5;71(13):5358-5371. doi: 10.1021/acs.jafc.3c00388. Epub 2023 Mar 21.
Three Amadori rearrangement products (Xyl-α-Lys-ARP, Xyl-ε-Lys-ARP, and diXyl-α,ε-Lys-ARP) were observed in the xylose-lysine (Xyl-Lys) Maillard reaction model. They were separated and characterized by liquid chromatography with tandem mass spectrometry and NMR. The crucial roles of reaction temperature, pH, molar ratio of Xyl to Lys, and reaction time in the formation of different Xyl-Lys-ARPs were investigated. The proportion of Xyl-α-Lys-ARP among all Xyl-Lys-ARPs was increased to 48.41% (its concentration was 25.31 μmol/mL) after the reaction at pH = 5.5 and a molar ratio of 3:1 (Xyl: Lys) for 9 min, while only Xyl-ε-Lys-ARP was generated at a higher pH (7.5) and a lower molar ratio of 1:5. Moreover, the much higher activation energy (84.08 kJ/mol) of diXyl-α,ε-Lys-ARP than Xyl-α-Lys-ARP (34.19 kJ/mol) and Xyl-ε-Lys-ARP (32.32 kJ/mol) indicated a pronounced promoting effect on diXyl-α,ε-Lys-ARP formation by high temperatures. A complete conversion from Xyl-α-Lys-ARP and Xyl-ε-Lys-ARP to diXyl-α,ε-Lys-ARP was achieved through the reaction time prolongation and Xyl concentration increase at a higher temperature; the concentration of diXyl-α,ε-Lys-ARP was 39.05 μmol/mL at a molar ratio of 5:1 for 40 min. Accordingly, the selective preparation of Xyl-α-Lys-ARP, Xyl-ε-Lys-ARP, and diXyl-α,ε-Lys-ARP could be achieved through adjusting the Xyl-Lys ratio, pH, and reaction time.
在木糖-赖氨酸（Xyl-Lys）美拉德反应模型中观察到三种阿玛多里重排产物（木糖-α-赖氨酸-ARP、木糖-ε-赖氨酸-ARP和二木糖-α,ε-赖氨酸-ARP）。它们通过液相色谱-串联质谱和核磁共振进行分离和表征。研究了反应温度、pH值、木糖与赖氨酸的摩尔比以及反应时间在不同木糖-赖氨酸-ARPs形成中的关键作用。在pH = 5.5、摩尔比为3:1（木糖:赖氨酸）反应9分钟后，木糖-α-赖氨酸-ARP在所有木糖-赖氨酸-ARPs中的比例增加到48.41%（其浓度为25.31 μmol/mL），而在较高pH值（7.5）和较低摩尔比1:5时仅生成木糖-ε-赖氨酸-ARP。此外，二木糖-α,ε-赖氨酸-ARP的活化能（84.08 kJ/mol）比木糖-α-赖氨酸-ARP（34.19 kJ/mol）和木糖-ε-赖氨酸-ARP（32.32 kJ/mol）高得多，这表明高温对二木糖-α,ε-赖氨酸-ARP的形成有显著的促进作用。通过在较高温度下延长反应时间和增加木糖浓度，实现了木糖-α-赖氨酸-ARP和木糖-ε-赖氨酸-ARP向二木糖-α,ε-赖氨酸-ARP的完全转化；在摩尔比为5:1反应40分钟时，二木糖-α,ε-赖氨酸-ARP的浓度为39.05 μmol/mL。因此，通过调节木糖-赖氨酸比例、pH值和反应时间，可以选择性地制备木糖-α-赖氨酸-ARP、木糖-ε-赖氨酸-ARP和二木糖-α,ε-赖氨酸-ARP。
