16味中药炮制前后抗氧化活性的比较研究

目的:比较16味中药炮制前后的抗氧化活性。方法:采用氧自由基清除能力(ORAC)法测定样品的抗氧化活性。荧光素(FL)为荧光探针。2,2-偶氮-2-氨基氢氯化丙烷在37℃时以稳定的速率产生过氧化氢(H2O2),H2O2氧化FL从而造成其荧光衰减。抗氧化剂的存在可以清除H2O2,延迟FL的荧光衰减,动态记录样品35min内的荧光变化。以水溶性维生素E为标准品绘制标准方程,根据Trolox标准方程计算样品的ORAC值。表儿茶素为阳性对照。结果:16味中药炮制前、后均具有一定的ORAC值,酒黄芩的ORAC值最高,为4241μmol TE·g-1;炒薏苡仁的ORAC值最低,为17μmol TE·g-1。10味中药炮制品的ORAC值低于生品,其中7味有显著性差异(P<0.05);6味炮制品的ORAC值高于生品,其中3味有显著性差异(P<0.05)。结论:16味中药炮制前、后抗氧化活性的变化可能与其所含的化学成分含量改变有关。

Antioxidant Activity of 16 Ingredients of Traditional Chinese Medicine and Their Processed Products

OBJECTIVE： To investigate the antioxidant activity of 16 ingredients of traditional Chinese medicine （TCM） and their processed products. METHODS： Antioxidant capacity of samples was measured by the Oxygen Radical Absorbance Capacity （ORAC） with fluorescein （FL） as fluorescent probe. Hydrogen peroxide （H2O2） was induced by 2’-Azobis（2-amidinopropane） dihydrochloride（AAPH） at 37 ℃ and stable velocity. Oxidation of FL which was induced by H2O2 resulted in fluorescence decay of FL. Anti-oxidant could scavenge H2O2 and delay the fluorescence decay of FL. The fluorescence change of samples was recorded within 35 min. Standard equation was established using water-soluble vitamin E （Trolox） as standard to calculate ORAC value of samples with epicatichin as positive control. RESULTS： 16 ingredients of TCM and their processed products all showed ORAC values. ORAC value of processed Scutellaria baicalensis was 4 241 μmol TE·g-1 and the highest value among 16 ingredients of TCM while processed Coix lacryma-jobi was 17 μmol TE·g-1 and the lowest value among them. ORAC value of 10 ingredients of raw TCM was higher than processed ones, there was significant difference among 7 ingredients of TCM（P〈0.05）. ORAC value of 6 ingredients of processed TCM was higher than raw TCM, there was significant difference among 3 ingredients of TCM（P〈0.05）. CONCLUSION： The difference of antioxidant activity of 16 ingredients of TCM and their processed products may be related to change of chemical components.