龙胆草及其提取物体外抗猪繁殖与呼吸综合征病毒作用的研究

为研究龙胆草水提取物、龙胆草总黄酮、龙胆草总苷体外抗猪繁殖与呼吸综合征病毒（PRRSV）的作用，本试验建立Marc-145细胞模型，在研究其对Marc-145细胞最大安全浓度的基础上，结合细胞病变形态观察和MTT法，设立药物组、利巴韦林阳性对照组、病毒对照组和细胞对照组，对病毒进行阻断、抑制和直接灭活3种作用方式的测定。结果显示，龙胆草水提取物、龙胆草总黄酮、龙胆草总苷和利巴韦林的最大安全浓度分别为6.250、0.020、0.630和0.016 mg/mL。在体外抗PRRSV作用的试验中，龙胆草水提取物对病毒的阻断、抑制和直接灭活作用的最高抑制率分别为43.1%、57.4%和56.4%，均低于阳性对照利巴韦林，且各作用方式下细胞均发生了明显病变。龙胆草总黄酮对病毒的阻断、抑制和直接灭活作用的最高抑制率分别为66.1%、41.1%和42.7%，其抑制作用和直接灭活作用的抑制率均低于阳性对照利巴韦林，阻断作用下细胞轻微病变。龙胆草总苷对病毒的阻断、抑制和直接灭活作用的最高抑制率分别为33.4%、78.2%和81.9%，其抑制和直接灭活作用较强，远高于阳性对照利巴韦林，且在这两种作用方式下细胞基本保持单层完好。综合3种作用方式，3种龙胆草提取物中龙胆草总苷抗PRRSV的效果最好，其次是龙胆草水提取物和龙胆草总黄酮。

Study on the Anti-porcine Reproductive and Respiratory Syndrome Virus Effect of Gentian and Its Extract

In order to study the water extract,total flavonoids and total glycosides of gentian in vitro against porcine reproductive and respiratory syndrome virus (PRRSV),the effect of Marc-145 cell model was established in this experiment.Based on the study of its maximum safe concentration of Marc-145 cells,combined with the observation of cytopathic morphology and MTT method,the drug group,ribavirin positive control group,virus control group and cell control group were set up to determine the three action modes of blocking,inhibition and direct inactivation to the virus,respectively.The results showed that the maximum safe concentrations of the water extract of gentian,total flavonoids of gentian,total glycosides of gentian and ribavirin were 6.250,0.020,0.630 and 0.016 mg/mL,respectively. In vitro anti-PRRSV effect of the test,the highest inhibition rates of the water extract of gentian on virus blocking,inhibition and direct inactivation effect were 43.1%,57.4% and 56.4%,respectively,which were all lower than that of ribavirin in the positive control group,and the cells had obvious pathological changes in each mode of action.The highest inhibition rates of the total flavonoids of gentian on virus blocking,inhibition and direct inactivation effect were 66.1%,41.1% and 42.7%,respectively.The inhibition rate of its inhibitory effect and direct inactivation effect were lower than that of ribavirin in the positive control group.The highest inhibition rates of the total glycosides of gentian on virus blocking,inhibition and direct inactivation effect were 33.4%,78.2% and 81.9%,respectively.The inhibition and direct inactivation were much stronger than that of ribavirin in the positive control group,and the cells basically kept the monolayer intact under the two action modes.Combined with the three action modes,among the three gentian extracts,the total glycosides of gentian had the best anti-PRRSV effect,followed by the water extract and the total flavonoids of gentian.