棕点石斑鱼中草药免疫增强剂的快速筛选

摘要

采用离体外周血白细胞与中草药水提液共同孵育法，快速筛选棕点石斑鱼中草药免疫增强剂。39种生药量浓度为100 mg/ml 的中草药水提液及添加5.0 mg/ml 酵母聚糖的中草药水提液分别与棕点石斑鱼外周血白细胞孵育后，采用氮蓝四唑(NBT)还原法检测各种中草药水提液对棕点石斑鱼外周血白细胞氧呼吸爆发活性的影响，再以吞噬乳胶微球法检测具有显著增强白细胞氧呼吸爆发活性效果的中草药对棕点石斑鱼白细胞吞噬活性的影响，筛选中草药免疫增强剂，并将其拌料饲喂棕点石斑鱼，考察其对棕点石斑鱼外周血和头肾白细胞氧呼吸爆发活性的影响。结果显示，39种中草药中有10种对棕点石斑鱼离体白细胞氧呼吸爆发活性显著提高15%以上，3种酵母聚糖添加组对白细胞氧呼吸爆发活性提高70%以上；筛选出可同时提高棕点石斑鱼离体白细胞的氧呼吸爆发活性和吞噬活性的 3种中草药，它们分别为鸡血藤、黄柏和墨旱莲。拌料饲喂实验结果显示，饲喂1%的鸡血藤、黄柏和墨旱莲可显著提高棕点石斑鱼体内外周血和头肾白细胞氧呼吸爆发活性。%Epinephelus fuscoguttatus is a new culturing breed with great commercial values and broad market prospects. Frequent invasion of disease restricts the development of E. fuscoguttatus industry. With the characteristics of pollution-free, low-toxic, and low residuals, Chinese herbs as immunostimulants may be candidates for the prevention and control the diseases among E. fuscoguttatus. In this study, Chinese herbal immunostimulants were screened using nitroblue tetrazolium (NBT) reduction method by incubating the isolated white blood cell with water extracts from Chinese herbs. Water extracts from 39 kinds of 100 mg/ml Chinese herbs mixed with or without 5.0 mg/ml zymosan were utilized. Phagocytizing latex beads was employed to determine the effect of water extracts on the respiratory burst activity of the white blood cells on the phagocytic activity. The screened Chinese herbal immunostimulants were mixed with the feedstuff to feed E. fuscoguttatus. The results showed that 10 Chinese herbs extracts significantly increased the respiratory burst of white blood cells more than 15%compared to those in the control group. Three Chinese herbs extracts mixed with zymosan significantly increased the respiratory burst of white blood cells more than 70%. The water extracts from Caulis spatholobi, Cortex phellodendri amurensis and Herba ecliptae prostratae simultaneously elevated the respiratory burst and the phagocytic activity of white blood cell of E. fuscoguttatus. The in vivo experiments also demonstrated that the water extracts from Caulis spatholobi, Cortex phellodendri amurensis and Herba ecliptae prostratae significantly elevated the respiratory burst and the phagocytic activity of white blood cell and head kidney white cells of E. fuscoguttatus. In this study, 3 Chinese herbal immunostimulants were screened, which significantly enhanced the immune responses in E. fuscoguttatus. These results provide evidence to the development and application of new, safe and effective immunostimulants of E. fuscoguttatus.