紫玉米花色苷抑制牛传染性鼻气管炎病毒在牛肾细胞中增殖的研究

为研究紫玉米花色苷(purple corn anthocynins，PCA)的抗病毒效果，本试验先通过观察细胞病变效应测定了PCA对牛肾细胞传代系MDBK细胞的毒性作用，以此确定PCA的安全浓度范围；然后以3-(4，5-二甲基噻唑-2)-2，5-二苯基四氮唑溴盐（MTT）法检测了安全浓度范围内的PCA对牛传染性鼻气管炎病毒在MDBK细胞中复制的影响。PCA毒性试验结果显示，PCA对MDBK细胞的最大安全浓度为262.14 μg/mL；而最小浓度为7.8125 μg/mL的PCA就能对牛传染性鼻气管炎病毒在MDBK细胞中的复制有明显抑制作用。MTT试验结果显示，PCA对MDBK细胞的半数抑制浓度（TC₅₀）为262.14 μg/mL，对病毒的半数抑制浓度（IC₅₀）为11.38 μg/mL，以此计算出治疗指数（TI）为23.04。由此证明PCA具有良好的抗牛传染性鼻气管炎病毒的作用，提示紫玉米可作为防制奶牛传染性鼻气管炎的饲料原料。

Study on Purple Corn Anthocyanin Inhibits Replication of Infectious Bovine Rhinotracheitis Virus on Bovine Kidney Cells

To investigate the effect of purple corn anthocyanins (PCA) on inhibiting infectious bovine rhinotracheitis virus (IBRV) in vitro, the toxicity of PCA on madin-darby bovine kidney cells (MDBK) was measured by observation of cytopathic effect (CPE).Then the inhibition effects of PCA on replication of IBRV were investigated within safe concentrations by MTT assay. The results showed the maximum safe concentration of PCA on MDBK cell was 262.14 μg/mL, whereas PCA could apparently inhibit the replication of IBRV on MDBK cells in very low dose (7.8125 μg/mL). The median inhibitory concentration (TC₅₀ and IC₅₀) of PCA to MDBK and IBRV was 262.14 and 11.38 μg/mL，individually. On consequence, the treatment index （TI） was calculated as 23.04. These data demonstrated that PCA had the function of anti-IBRV, and suggested that purple corn could be as a feed material for prophylaxis and treatment of infectious bovine rhinotracheitis in dairy cows.