Bacterial infections are the most important problem of health care worldwide. The hemolymph antibacterial proteins of Mesocyclops leuckarti was isolated for the first time and its antibacterial efficacy was evaluated against four different human pathogenic microbes viz., Escherichia coli, Staphylococcus aureus, Klebsiella pneumonia and Shigella flexneri. The antibacterial potential of the antimicrobial proteins of hemolymph samples from plankton cultured in water enriched with Cow Urine Distillate (CUD) was compared with normal ones. The results indicated that the hemolymph proteins were more potential against Gram negative bacteria than Gram positive bacteria. Klebsiella pneumonia was more susceptible to the hemolymph proteins exhibiting a zone of inhibition measuring 27 mm. The supplement of CUD to the culture media further enriched the antibacterial activity of the hemolymph proteins (29 mm). The SDS-PAGE analysis indicated two different types of clear bands representing proteins of 53 kDa and 19 kDa. Overall, this investigation signified that the microcrustaceans have a defence mechanism hemolymph of Mesocyclops leuckarti have a potential agent for novel antibiotics.

细菌感染是全世界卫生保健中最重要的问题。首次分离了Mesocyclops leuckarti的血淋巴抗菌蛋白，并评估了其对四种不同的人类致病性微生物（即大肠杆菌，金黄色葡萄球菌，肺炎克雷伯菌和肺炎志贺氏菌）的抗菌效果。比较了在富含牛尿馏出物（CUD）的水中培养的浮游生物血淋巴样品的抗菌蛋白的抗菌潜力。结果表明，相比于革兰氏阳性细菌，血淋巴蛋白对革兰氏阴性细菌的潜力更大。肺炎克雷伯菌对血淋巴蛋白更敏感，其表现出抑制区域为27 mm。在培养基中添加CUD可以进一步丰富血淋巴蛋白（29毫米）的抗菌活性。SDS-PAGE分析表明两种不同类型的透明带，分别代表53 kDa和19 kDa的蛋白质。总体而言，这项调查标志着该microcrustaceans具有的防御机制血淋巴中剑leuckarti对新型抗生素潜在代理。