超高效液相色谱-串联质谱法同时测定茶叶中烟酰胺腺嘌呤二核苷酸及其4种前体化合物含量

Simultaneous Determination of Nicotinamide Adenine Dinucleotide and Its Four Precursors in Tea by Ultra-high Performance Liquid Chromatography-Tandem Mass Spectrometry

烟酰胺核糖体(NR)、烟酰胺单核苷酸(NMN)、烟酸(NA)和烟酰胺(NAM)是烟酰胺腺嘌呤二核苷酸(NAD^(+))的4个前体化合物,口服后可在体内转化为NAD^(+)发挥抗衰老等功效。建立了采用超高效液相色谱-串联质谱法(UPLC-MS/MS)同时测定茶叶中NAD^(+)及其4种前体化合物含量的方法,茶叶经水提取,稀释后直接进行UPLC-MS/MS分析。经方法学验证,5种目标化合物在各自范围内线性关系良好(R^(2)≥0.99),回收率为70.00%~120.00%,相对标准偏差为2.09%~14.50%,方法的定量限为0.10~0.50μg·L^(-1)。绿茶、红茶和黑茶中5种目标化合物的含量测定结果显示,绿茶和红茶是NR、NMN、NAD^(+)的良好天然食物来源;主成分分析结果显示,根据5种化合物含量能对红茶、绿茶、黑茶进行良好的类群区分;聚类分析结果显示,同一产地同一类型茶叶中5种化合物质量分布不均,离散度较高,无法进行区分。

Nicotinamide ribosome(NR),nicotinamide mononucleotide(NMN),nicotinic acid(NA)and nicotinamide(NAM)are 4 precursor compounds of NAD^(+),which can be converted to NAD^(+)in vivo to work after oral administration.This study established a method for simultaneous determination of NAD^(+)and its four precursors in tea by ultra-high performance liquid chromatography-tandem mass spectrometry.The tea samples were extracted by water,then diluted and directly analyzed by UPLC-MS/MS.Method validation shows this method has good linearity in their respective range with correlation coefficients(R^(2))higher than 0.99.The average recoveries ranged from 70.00%to 120.00%with relative standard deviations(RSDs)of 2.09%-14.50%.The limits of quantitation(LOQs)were 0.10-0.50μg·L^(-1).The determination results of five target compounds in green tea,black tea and dark tea show that green tea and black tea were the good natural food sources of NR,NMN,NAD^(+).The results of principal component analysis show that the contents of five compounds could well distinguish black tea,green tea and dark tea.The cluster analysis shows the same type of tea from the same origin was of uneven quality,with high dispersion in samples,and it was difficult to identify each other.