In this study, the identification and characterization of potential probiotic bacteria present in natural microbiota of tambaqui Colossoma macromum were performed for the first time. Bacteria from the intestinal mucosa were isolated in agar Man, Rogosa and Sharpe (MRS). Only Gram‐positive and haemolysis‐negative isolates were selected (n = 152). The tests included morphological differentiation, gene sequencing, catalase, bile tolerance, pathogen antagonism, antimicrobial susceptibility and safety to the host. To differentiate the isolates, colonies were morphologically characterized. From 152 initial isolates, 6 strains with probiotic potential were selected and identified through sequencing of 16S rRNA gene of Enterococcus faecalis, Enterococcus hirae, Lactococcus lactis, Pediococcus pentosaceus, Staphylococcus hominis and Staphylococcus saprophyticus. The growth of the six strains was not affected by different levels of bile inclusion. All probiotic strains inhibited the growth of the Lactococcus garvieae pathogen in the antagonism test. When tested against Aeromonas hydrophila, L. lactis and E. hirae strains were prominent. All strains were resistant to some degree against the 11 antibiotics. With this study, it was possible to screen the following six strains with probiotic potential for inclusion in the diet of C. macropomum: S. hominis, S. saprophyticus, L. lactis, P. pentosaceus, E. hirae and E. faecalis.

中文翻译：

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坦巴基巨像中土生细菌的益生菌潜力

在这项研究中，首次对坦巴基巨像的天然菌群中存在的潜在益生菌进行了鉴定和表征。从琼脂糖，Rogosa和Sharpe（MRS）中分离出肠粘膜中的细菌。仅选择革兰氏阳性和溶血阴性的分离株（n = 152）。测试包括形态学分化，基因测序，过氧化氢酶，胆汁耐受性，病原体拮抗作用，抗菌药敏感性和对宿主的安全性。为了区分分离株，对菌落进行了形态学表征。从152株初始菌株中筛选出6株具有益生菌潜力的菌株，并通过粪肠球菌，平肠肠球菌，乳酸乳球菌，戊糖球菌，人葡萄球菌和腐生葡萄球菌。六个菌株的生长不受不同水平的胆汁包涵物的影响。在拮抗试验中，所有益生菌菌株均能抑制加维乳球菌病原体的生长。当针对测试嗜水，乳酸乳球菌和希拉肠球菌菌株突出。所有菌株对11种抗生素都有一定程度的抗性。通过这项研究，有可能筛选出以下六种具有益生菌潜能的菌株，这些菌株可能被包含在大果梭菌的饮食中：S. hominis，腐生葡萄球菌，乳酸乳球菌，戊糖片球菌，希拉肠球菌和粪肠球菌。