RESUMO
Objective The aims of this study were to develop an ultraviolet-visible spectrophotometry (UV-Vis) for the determination of quaternary ammonium alkaloid content in Lycium ruthenicumMurr., and to analysis the constitution of its nitrogenous compounds by liquid chromatograph - mass spectrometry(LC-MS). Methods The quaternary ammonium alkaloid content was determined by a UV-Vis spectrophotometer at 524 nm. The ultra performance liquid chromatography(UPLC) analysis was performed on BOS Hypersil C18 column(2.1 mm × 150 mm, 2.4μm), with 0.1％ formic acid solution(A)–acetonitrile(B) as the mobile phase for gradient elution. The flow rate was 0.3 ml/min, and the column temperature was 35℃, Multiple reaction monitoring (MRM) equipped with electrospray ion source was performed in positive ion mode for structure analysis.Results As a standard, the betaine was linear in the range of 981μg-4906μg,Y=0.0001X-0.0055, r=0.9993, and the average recovery rate was 98.53％,RSD=1.19％(n=6). There were 12 nitrogenous compounds analyzed by LC-MS, with N(1)-dihydrocaffeoyl-N(12)-caffeoyl spermine and p-Hydroxyl-cinnamyl-dihydrocaffeoyl spermidine were first reported.Conclusions The method developed in this subject is simple, accurate with good repeatability, which can be applied for determination of quaternary ammonium alkaloid content in Lycium ruthenicumMurr. And the structure analysis of its nitrogenous compounds will deepen the understanding of the compounds inLycium ruthenicumMurr.