Delgado S, O'Sullivan E, Fitzgerald G, Mayo B
Departamento de Microbiología y Bioquímica, Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Villaviciosa, Spain.
J Appl Microbiol. 2008 Apr;104(4):1119-27. doi: 10.1111/j.1365-2672.2007.03642.x. Epub 2008 Jan 31.
The aim of this work was to identify and select new probiotic strains among majority intestinal bifidobacterial species from healthy Spaniards.
One hundred and eighty isolates belonging to seven Bifidobacterium species were subjected to a subtractive system of in vitro analysis addressing beneficial and undesirable traits. Approx. 45% of the isolates were able to grow in 2% bovine bile, and about 20% of these grew at pH 3.5. Undesirable enzymatic activities, such as alpha-chymotrypsin, beta-glucuronidase and N-acetyl-beta-glucosaminidase were not detected. Atypical antibiotic resistances were not observed, except for tetracycline resistance in a single strain. Intestinal pathogens were inhibited to some extent by all analysed strains. All selected strains adhered to human epithelial cells in a strain-dependent manner, and none was able to degrade pig mucin.
Based on these in vitro analyses, strains of Bifidobacterium catenulatum, Bifidobacterium longum and Bifidobacterium pseudocatenulatum are here proposed as new probiotic candidates.
Although in vivo analyses are still needed, these strains belonging to unusual species in the portfolio of probiotic suppliers are thought to be more appropriated than those currently in use, as they show desirable properties and are preponderant among human intestinal populations.
本研究旨在从健康西班牙人的肠道双歧杆菌中鉴定并筛选新的益生菌菌株。
对属于7种双歧杆菌的180株分离株进行了体外分析的消减系统，以评估其有益和不良特性。约45%的分离株能够在2%的牛胆汁中生长，其中约20%能在pH 3.5条件下生长。未检测到诸如α-糜蛋白酶、β-葡萄糖醛酸酶和N-乙酰-β-氨基葡萄糖苷酶等不良酶活性。除了一株对四环素耐药外，未观察到非典型抗生素耐药性。所有分析的菌株都能在一定程度上抑制肠道病原体。所有筛选出的菌株都以菌株依赖的方式黏附于人上皮细胞，且无一株能够降解猪黏蛋白。
基于这些体外分析，本文提出链状双歧杆菌、长双歧杆菌和假链状双歧杆菌菌株作为新的益生菌候选菌株。
尽管仍需要进行体内分析，但这些属于益生菌供应商产品组合中不常见物种的菌株被认为比目前使用的菌株更合适，因为它们具有理想的特性，且在人类肠道菌群中占优势。
