分光光度法测定火龙果茎中黄酮类化合物的含量

AlCl_3 spectrophotometric determination of flavonoids in pitaya stems

火龙果是仙人掌三角柱属多年生植物,其果具有丰富的营养价值,可作为水果直接食用,花也可以作为蔬菜,而火龙果茎却未被利用。本文研究了火龙果茎中黄酮类化合物的分离提取和测定方法。采用单因素实验和正交试验对黄酮类化合物的分光光度法测定条件和火龙果茎中黄酮类化合物的分离提取条件进行优化。实验结果表明,以芦丁为标样,黄酮含量在6.64～44.8mg/L范围内服从比尔定律,回归方程为A=0.333ρ-5.14×10-3,相关系数R=0.9999;火龙果茎中黄酮类化合物的分离提取条件为:70%的乙醇溶液为提取溶剂,料液比为1:40,提取温度为75℃,提取时间3h。方法回收率为96.1%～102.2%,相对标准偏差(RSD)为3.3%(n=5)。火龙果茎干品中黄酮类化合物的含量为0.49%。

Pitaya is a perennial plant with triangular cactus genus,of which fruit is rich in nutritional value and can be ate directly,flowers can be used as vegetables,but the pitaya stems are not being used.In this paper,the extraction and separation of the total flavones from pitaya stems were studied by using single-factor experiments and orthogonal test to optimize process conditions.Regression equation is A=0.333ρ-5.14×10^-3,correlation coefficient R=0.99986.The absorbance（A）was linear with the concentration is in the range of 6.4～44.8mg/L.The recoveries and RSD are 96.1%～102.2% and 3.3% respectively（n=5）.The result showed that the content of total flavones from dry pitaya stem is 0.49%.