Egirdir Fisheries Faculty, Isparta University of Applied Sciences, 32260, Isparta, Turkey.
Department of Aquatic Animal Diseases, Faculty of Veterinary Medicine, Ondokuz Mayis University, Samsun, 55139, Turkey.
Microb Pathog. 2023 Nov;184:106381. doi: 10.1016/j.micpath.2023.106381. Epub 2023 Oct 6.
In aquaculture, probiotic yeasts have gained particular interest because of their numerous health benefits for farmed fish. Many autochthonous yeasts have been isolated and identified from fish species with potential probiotic characteristics. In the present study, four autochthonous yeast strains were identified and characterized from the intestinal tracts of 16 healthy goldfish, Carassius auratus. Their in vitro probiotic properties were examined in terms of cell surface hydrophobicity, co-aggregation, and tolerability to different pH values and bile salt concentrations. These strains were identified by culture characters and sequence analysis of ITS (Internal Transcribed Spacer) gene regions. Four strains, namely Cutaneotrichosporon jirovecii isolate jpn01, Debaryomyces nepalensis isolate jpn02, Blastobotrys proliferans isolate jpn05, and Diutina catenulata isolate jpn06, were identified and added to the NCBI GenBank with accession numbers defined as MT584874.1, MT584873.1, MT649918.1, and MT501155.1, respectively. Results demonstrated the capability of these strains to co-aggregate with several fish-associated bacterial pathogens such as Lactococcus garvieae, Vagococcus salmoninarum, Vibrio anguillarum, Yersinia ruckeri, and Aeromonas hydrophila. Only the jpn05 strain did not co-aggregate with A. hydrophila. All identified yeast isolates could grow and tolerate low pH conditions (pH 2.0) and bile salt concentrations (up to 1.5%). Of interest, the hydrophobicity (%) of the yeast isolates was 80%, 94.0%, 80.6%, and 66.4% for jpn01, jpn02, jpn05, and jpn06 isolates, respectively. In this context, our data provide important in vitro evidence for the potential probiotic features of the yeast isolates. These strains could be considered candidate probiotic yeasts; however, their application in aquaculture nutrition necessitates further in vivo assays.
在水产养殖中，由于益生菌酵母对养殖鱼类有许多健康益处，因此引起了特别关注。已经从具有潜在益生菌特性的鱼类物种中分离和鉴定了许多本土酵母。在本研究中，从 16 条健康金鱼（Carassius auratus）的肠道中分离和鉴定了四种本土酵母菌株。根据细胞表面疏水性、共聚和对不同 pH 值和胆汁盐浓度的耐受性，研究了它们的体外益生菌特性。这些菌株通过培养特征和 ITS（内部转录间隔区）基因区域的序列分析进行鉴定。四种菌株，即表皮毛孢子菌分离株 jpn01、德巴利酵母分离株 jpn02、丛生枝孢菌分离株 jpn05 和链状迪蒂纳酵母分离株 jpn06，通过培养特征和 ITS 基因区域的序列分析进行鉴定，并添加到 NCBI GenBank 中，登录号分别为 MT584874.1、MT584873.1、MT649918.1 和 MT501155.1。结果表明，这些菌株能够与几种鱼类相关的细菌病原体如乳酸乳球菌、鲑鱼弧菌、鳗弧菌、鲁氏耶尔森菌和嗜水气单胞菌共聚。只有 jpn05 菌株不能与嗜水气单胞菌共聚。所有鉴定的酵母分离株都可以在低 pH 值（pH 2.0）和胆汁盐浓度（高达 1.5%）下生长和耐受。有趣的是，酵母分离株的疏水性（%）分别为 jpn01、jpn02、jpn05 和 jpn06 分离株的 80%、94.0%、80.6%和 66.4%。在这种情况下，我们的数据为酵母分离株的潜在益生菌特性提供了重要的体外证据。这些菌株可以被认为是候选益生菌酵母；然而，它们在水产养殖营养中的应用需要进一步的体内试验。
