Abstract:
Vibrio parahaemolyticus is a gram-negative facultative anaerobic bacterium implicated as the causative agent of several shrimp diseases. As part of the effort to provide biocontrol and cost-effective treatments, this research was designed to elucidate the effect of Morinda citrifolia fruit extract on the immunity of Penaeus vannamei postlarvae (PL) to V. parahaemolyticus. The methanol extract of M. citrifolia was vacuum evaporated, and the bioactive compounds were detected using gas chromatography‒mass spectrometry (GC‒MS). Thereafter, P. vannamei PL diets were supplemented with M. citrifolia at different concentrations (0, 10, 20, 30, 40, and 50 mg/g) and administered for 30 days before 24 h of exposure to the bacterium V. parahaemolyticus. A total of 45 bioactive compounds were detected in the methanol extract of M. citrifolia, with cyclononasiloxane and octadecamethyl being the most abundant. The survival of P. vannamei PLs fed the extract supplement was better than that of the control group (7.1-26.7% survival greater than that of the control group) following V. parahaemolyticus infection. Shrimp fed 50 mg/g M. citrifolia had the highest recorded survival. The activities of digestive and antioxidant enzymes as well as hepatopancreatic cells were significantly reduced, except for those of lipase and hepatopancreatic E-cells, which increased following challenge with V. parahaemolyticus. Histological assessment of the hepatopancreas cells revealed reduced cell degeneration following the administration of the plant extracts (expecially those fed 50 mg/g M. citrifolia) compared to that in the control group. Therefore, the enhanced immunity against V. parahaemolyticus infection in P. vannamei could be associated with the improved hepatopancreas health associated with M. citrifolia fruit extract supplementation.
摘要:
副溶血性弧菌是一种革兰氏阴性兼性厌氧菌,是几种虾类疾病的病原体。作为提供生物防治和具有成本效益的治疗的努力的一部分,本研究的目的是阐明巴林达果实提取物对凡纳滨对虾后幼虫(PL)对副溶血性弧菌免疫的影响。将荆棘分枝杆菌的甲醇提取物真空蒸发,并使用气相色谱-质谱(GC-MS)检测生物活性化合物。此后,南美白对虾PL饮食中添加不同浓度(0、10、20、30、40和50mg/g)的西叶分枝杆菌,并在暴露于副溶血性弧菌24小时前给药30天。共检测到45个生物活性化合物的甲醇提取物中,其中环硅氧烷和十八甲基是最丰富的。副溶血性弧菌感染后,饲喂提取物补充剂的南美白对虾PLs的存活率优于对照组(存活率比对照组高7.1-26.7%)。饲喂50mg/g的虾。有记录的最高存活率。消化和抗氧化酶以及肝胰腺细胞的活性显着降低,除了脂肪酶和肝胰腺E细胞,在副溶血性弧菌攻击后增加。肝胰腺细胞的组织学评估显示,与对照组相比,施用植物提取物后(尤其是饲喂50mg/g的柑橘提取物)的细胞变性减少。因此,凡纳滨对虾对副溶血性弧菌感染的免疫力增强可能与补充柠檬酸根霉果实提取物相关的肝胰腺健康改善有关。