The development of intensive aquaculture industry has aggravated the dangers of ammonia and nitrite in aquatic ecosystems. Probiotics have been widely used to maintain and improve water quality by removal of ammonia and nitrite in aquaculture. In this study, two facultative anaerobic strains AB15 and NB14, capable of efficient ammonia and nitrite removal, were isolated from biofloc, which acts as a natural micro-flora storeroom in shrimp culture ponds, and were identified as Vibrio sp. and Pseudomonas fluorescens, respectively. The removal efficiency of ammonia and nitrite by AB15 and NB14 was 96.8 and 89.6%, respectively. The optimum conditions of AB15 and NB14 were as follows: temperature (25°C vs. 30°C), salinity (25‰ both), initial pH (7.5 vs. 8.0), C/N ratio (15 vs. 10). The two strains had great performance on inhibiting the common pathogens (Vibrio harveyi, Vibrio splendidus, Vibrio anguillarum) in aquaculture at concentrations of 10⁵–10⁸ CFU/mL. Biosecurity assessment indicated that both AB15 and NB14 were harmless for survival and could be beneficial for the growth and immune enhancement of Litopenaeus vannamei. All results demonstrate that the two isolated strains have high promise for future applications of removing ammonia and nitrite and maintaining biosecurity in shrimp culture ponds.

中文翻译：

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弧菌的表征。AB15 菌株和荧光假单胞菌菌株 NB14 来自虾养殖池塘的生物絮团，具有高氨和亚硝酸盐去除效率

集约化养殖业的发展加剧了氨和亚硝酸盐对水生生态系统的危害。益生菌已被广泛用于通过去除水产养殖中的氨和亚硝酸盐来维持和改善水质。在这项研究中，从生物絮团中分离出两种兼性厌氧菌株 AB15 和 NB14，它们能够有效去除氨和亚硝酸盐，作为对虾养殖池塘中的天然微生物菌群储藏室，并被鉴定为弧菌属。和荧光假单胞菌， 分别。AB15和NB14对氨和亚硝酸盐的去除效率分别为96.8%和89.6%。AB15和NB14的最佳条件如下：温度（25°C vs. 30°C）、盐度（均为25‰）、初始pH（7.5 vs. 8.0）、C/N比（15 vs. 10）。两种菌株对抑制常见的病原体大的性能（哈氏弧菌，灿烂弧菌，鳗弧菌在水产养殖中在10个浓度）⁵ -10 ⁸  CFU / mL的。生物安全评估表明AB15和NB14对生存无害，可能有利于南美白对虾的生长和免疫增强. 所有结果表明，这两种分离的菌株在未来去除氨和亚硝酸盐以及维持对虾养殖池塘生物安全方面的应用前景广阔。