水晶冰菜总黄酮提取工艺优化、结构表征及组成成分分析

本研究优化了超声辅助法提取水晶冰菜总黄酮的条件并对其结构和组成成分进行了深入分析。以得率为指标，在单因素实验基础上，对料液比、浸提时间、温度和功率四个因素进行正交试验，得出最优提取条件；在此条件下采用D101大孔树脂纯化水晶冰菜总黄酮，通过紫外可见光谱(UV-Vis)、傅立叶变换红外光谱(FT-IR)对纯化前后总黄酮的结构表征，最后采用超高效液相色谱串联质谱法(UPLC-MS/MS)分析纯化物组成成分。结果表明:最优提取条件为乙醇浓度60%，料液比1:25 mg/mL，超声温度45 ℃，时间120 min，功率250 W，得率可达2.776%；通过UV-Vis分析水晶冰菜总黄酮具有C6-C3-C6特征结构，傅立叶变换红外光谱FT-IR也显示其含有O-H、C-H、C=O、C=C、酚羟基等多种特征官能团的振动吸收峰，符合黄酮类化合物的典型结构；通过UPLC-MS/MS检测到纯化物中含有桔皮素、川橙皮素、杜鹃素、原儿茶醛、地奥司明、柚皮苷查尔酮、甜橙黄酮、柚皮素、芦丁等30多种黄酮类化合物，其中桔皮素的相对百分含量最高，为50.854%±0.089%。本研究将为水晶冰菜功能性的开发利用提供理论依据。

Optimization of Extraction Process,Structural Characterization and Component Analysis of Total Flavonoids from Mesembryanthemum crystallinum

In this study,the ultrasound-assisted extraction conditions of total flavonoids were optimized,and the structure and composition of total flavonoids were further analyzed.On the basis of single factor experiments,orthogonal experiments was carried out on four factors,including solid-liquid ratio,extraction time,temperature and power to obtain the optimal extraction conditions based on extraction yield.Under these conditions,total flavonoids were purified by D101 macroporous resin.The structure of total flavonoids before and after purification was characterized by UV-Vis and Fourier transform infrared spectroscopy(FT-IR).Finally,the constituents of the purified compounds were analyzed by ultraperformance liquid chromatography tandem mass spectrometry(UPLC-MS/MS).The results showed that the optimal extraction conditions were as follows:Ethanol concentration of 60%,solid-liquid ratio of 1:25 mg/mL,ultrasonic temperature of 45℃,time of 120 min,power of 250 W,and extraction yield of 2.776%.The characteristic structure of total flavonoids was analyzed by UV-Vis spectroscopy(UV-Vis).Fourier transform infrared spectroscopy(FT-IR)also showed that the total flavonoids contained O-H,C-H,C=O,C=C,phenolic hydroxyl groups and other characteristic functional groups,which was consistent with the typical structure of flavonoids.Thirty flavonoids were detected in the purified products by UPLCMS/MS,including citrinin,hesperetin,azalea,protocatechualdehyde,diosmin,naringin chalcone,sweet orange flavone,naringin and rutin.The relative content of citrinin was the highest,which was 50.854%±0.089%.This study would provide a theoretical basis for the functional development and utilization of crystal Mesembryanthemum crystallinum.