铜锤玉带草果实总黄酮的提取工艺研究

Extraction Process of Total Flavonoids from Pratia Begoniifolia

以铜锤玉带草的果实为实验材料,采用乙醇加热回流法提取其总黄酮,NaNO2-Al(NO3)3-NaOH显色法显色后,紫外-分光光度法测定总黄酮含量。采用单因素法确定不同提取条件对总黄酮的提取量的影响,通过正交试验和验证试验,选定最佳提取工艺。然后用此工艺条件提取不同成熟度的果实和植物不同部位的总黄酮,比较其含量。实验结果证明:乙醇加热回流法提取黄酮工艺的影响因素由高到低依次为:提取温度>料液比>提取时间>乙醇浓度。铜锤玉带草果实总黄酮最佳提取工艺为:温度55℃,乙醇浓度70%,料液比1∶20,提取时间40 min。在此条件下总黄酮的提取量为5.3548 mg/g。并比较了不同成熟度果实和植物不同部位的总黄酮含量,随着果实成熟,总黄酮含量逐渐增加;枝和叶的总黄酮含量分别为2.4022,4.5206 mg/g。

The fruit of Pratia begonifolia as the experimental material,the total flavonoids were extracted by heating and refluxing method with ethanol.With NaNO2-Al(NO3)3-NaOH color development method,the total flavonoid content was determined by UV-spectrophotometry.The single factor method was used to determine the effect of different extraction conditions on the extraction of total flavonoids,and the best extraction process was selected through orthogonal test and verification test.The experimental results showed that the influencing factors of the extraction process of flavonoids by heating and refluxing with ethanol from high to low were as follows:extraction temperature>material-liquid ratio>extraction time>ethanol concentration.The best extraction process of total flavonoids in the fruit of Pratia begonifolia was:temperature 55℃,ethanol concentration 70%,material-liquid ratio 1∶20,extraction time 40 min.Under this condition,the total flavonoid extraction amount was 10.7098,5.3548 mg/g.Because with the fruit maturing the total flavonoid content increased gradually,and that from the branches and leaves were 2.4022 mg/g and 4.5206 mg/g,respectively,the dark purple fruit was more suitable as the raw material for extraction.