粗制及精制蓝靛果花色苷的稳定性和抗氧化性研究

Stability and antioxidant activity of anthoyanins from Lonicera edulis

通过对蓝靛果花色苷的提取粗制品和纯化的精制品进行稳定性和体外抗氧化活性的比对实验,考察了p H、光照、温度、过氧化氢、糖等对蓝靛果花色苷稳定性的影响,并比较了其总还原力和清除DPPH自由基、羟自由基的抗氧化性能力。结果表明:在避光和p H为1、3的条件下,蓝靛果花色苷的保存率达85%以上,稳定性较好,且花色苷粗制品的稳定性优于精制品;随着处理温度的升高,花色苷的稳定性急剧下降,在50℃以下花色苷较稳定;在一定浓度范围内,葡萄糖、乳糖、蔗糖和淀粉对蓝靛果花色苷稳定性均具有增强作用,过氧化氢对花色苷有严重的破坏作用,且花色苷粗制品的耐氧化性明显强于精制品。此外,抗氧化性对比实验发现蓝靛果花色苷具有较强的还原能力,清除DPPH自由基、羟自由基的能力,通过比较花色苷粗制品及精制品的EC50值可知,这两种花色苷制品的总还原能力及清除羟自由基的能力略弱于同质量浓度的VC,但清除DPPH自由基的能力均强于同质量浓度的VC,且花色苷精制品的抗氧化能力明显强于粗制品。

By comparing the stability and antioxidant activity in vitro of the extracted crude product with that of the refined product of the Lonicera edulis anthocyanins,the experiment discussed the effect of p H,light,temperature,H2O2 and sugar on the stability of the Lonicera edulis anthocyanins,and compared its total reduction capacity,scavenging capacity of DPPH and hydroxyl free radicals. The results showed that the preserved rate of the Lonicera edulis anthocyanins reached more than 85% under the condition of dark and p H1.0 and 3.0,and the stability of the crude product was better than the refined product. The stability of anthocyanins decreased with the increase of temperature,and anthocyanins was stable at the temperature lower than 50 ℃. The stability of anthocyanins was enhanced by addition of glucose,maltose,lactose and starch in certain range. Anthocyanins was badly damaged by H2O2. In addition,it was concluded that the Lonicera edulis anthocyanins had strong scavenging capacity of DPPH free radical, hydroxyl free radical and the reduction capacity. By comparing the EC50 value of the crude product and the refined product,the results found that the reduction capacity and the scavenging capacity of hydroxyl free radical of these two products were stronger than VCof the same mass concentration,but the scavenging effect on DPPH free radical were weaker than VC,and the antioxidant activity of the refined product was significantly stronger than the crude product.