鹅掌楸碱的抗氧化性及稳定性研究

Study on the Antioxidant Activity and Stability of Liriodenine

采用DPPH法评价鹅掌楸碱的抗氧化活性及在不同理化条件下的稳定性.方法:采用DPPH作为自由基体系,通过测定加入鹅掌楸碱后对DPPH溶液吸光度值的改变来计算出鹅掌楸碱对DPPH自由基的清除率和IC50值,以此评价鹅掌楸碱的抗氧化活性;另外,测定鹅掌楸碱受到光,热和酸碱介质处理前后鹅掌楸碱吸光度值的改变,以此评价鹅掌楸碱在这些理化条件下的稳定性.实验表明鹅掌楸碱对DPPH自由基的IC50值为0.70mg/mL.其在弱碱性介质中可稳定存在,5小时60℃恒温处理对鹅掌楸碱稳定性无明显影响,然而在酸性介质或者室内自然光照射会引起吸光度值的下降.鹅掌楸碱具有一定的抗氧化活性,在室温,避光和弱碱性介质下可稳定存在.

To evaluate the antioxidant activity of Liriodenine by DPPH method, and the stability in different physio- chemical conditions, using DPPH as free radical system, the antioxidant activity of Liriodenine was evaluated by the clearance rate and the ICso value, which was calculated from the absorption value of residue DPPH after introducing Liriodenine to be antioxidant; and the stability of Liriodenine in different physiochemical conditions was evaluated on the different absorption value after treating by light, heat and acid-base medium. The result showed that the IC50 value of Liriodenine scavenging the DPPH free radical was 0.70 mg/mL. The stability experiments showed that Liriodenine is stable in weak alkaline medium and 60 ℃ heating treatment for 5 h. Liriodenine exhibits weak antioxidant activity with IC50= 0.70 mg/mL to DPPH free radical, and can exist stably in room temperature, avoiding light and weak alkaline medium.