连翘花总黄酮含量的分光光度法测定及其对NO^(2-)清除作用

Study on Determination and Scavenging Action of Total Flavonoids in Fructus Suspensa Flowers

利用不同溶剂提取连翘花中总黄酮,分光光度法测定了其中总黄酮含量,并研究了其对亚硝酸盐的清除能力。结果表明:连翘花总黄酮最佳提取试剂为50%乙醇溶液,含量测定最佳显色体系为NaNO_2-Al(NO_3)_3-NaOH显色体系,最佳测定时间为显色反应后20~40min范围内,测定方法精密度RSD=0.67%(n=5),加标回收率为102.67%(RSD=1.16%),利用该法测得连翘花总黄酮含量为12.74%(RSD=2.71%,n=5);在模拟胃液条件下,连翘花总黄酮浓度从8.00μg/mL增加至96.00μg/mL时,清除率从(27.69±2.10)%逐渐增加至(96.08±0.90)%,IC50值为18.05μg/mL,该测定方法简便可靠,连翘花总黄酮对亚硝酸盐具有很强的清除作用。

The content of total flavonoids in Fructus Suspensa flowers was determined by spectrophotome- try, and then the scavenging ability of extractive on nitrite. The results showed that the content of total flavonoids was determined using NaNO2- Al（NO3）3- NaOH chromogenic system and spectrophotometry. The optimal time to scan the absorption spectrum was 20 min ≤t≤40 min. The relative standard devia- tion RSD of precision test was 0.67G （n=5）. The mean recovery rate was 102.67% （RSD=1.16%）and total flavonoids yield in Fructus Suspensa flowers sample was 12.74%（RSD= 2.71%, n= 5）. In mimic gastric juice, the clearance rate increased from （27.69 ± 2.10）% to （96.08±0.90）% when the average of flavonoids was from 8.00 μg/mL to 96.00 μg/mL, the IC50 was 18.05 μg/mL. Therefore, the content of total flavonoids in Fructus Suspensa flowers has excellent clearance effect on nitrite.