Department of Odontology/Cariology section, Umeå University, Umeå, Sweden.
BMC Microbiol. 2013 Aug 15;13:193. doi: 10.1186/1471-2180-13-193.
Lactobacillus species can contribute positively to general and oral health and are frequently acquired by breastfeeding in infancy. The present study aimed to identify oral lactobacilli in breast and formula-fed 4 month-old infants and to evaluate potential probiotic properties of the dominant Lactobacillus species detected. Saliva and oral swab samples were collected from 133 infants who were enrolled in a longitudinal study (n=240) examining the effect of a new infant formula on child growth and development. Saliva was cultured and Lactobacillus isolates were identified from 16S rRNA gene sequences. Five L. gasseri isolates that differed in 16S rRNA sequence were tested for their ability to inhibit growth of selected oral bacteria and for adhesion to oral tissues. Oral swab samples were analyzed by qPCR for Lactobacillus gasseri.
43 (32.3%) infants were breastfed and 90 (67.7%) were formula-fed with either a standard formula (43 out of 90) or formula supplemented with a milk fat globule membrane (MFGM) fraction (47 out of 90). Lactobacilli were cultured from saliva of 34.1% breastfed infants, but only in 4.7% of the standard and 9.3% of the MFGM supplemented formula-fed infants. L. gasseri was the most prevalent (88% of Lactobacillus positive infants) of six Lactobacillus species detected. L. gasseri isolates inhibited Streptococcus mutans binding to saliva-coated hydroxyapatite, and inhibited growth of S. mutans, Streptococcus sobrinus, Actinomyces naeslundii, Actinomyces oris, Candida albicans and Fusobacterium nucleatum in a concentration dependent fashion. L. gasseri isolates bound to parotid and submandibular saliva, salivary gp340 and MUC7, and purified MFGM, and adhered to epithelial cells. L. gasseri was detected by qPCR in 29.7% of the oral swabs. Breastfed infants had significantly higher mean DNA levels of L. gasseri (2.14 pg/uL) than infants fed the standard (0.363 pg/uL) or MFGM (0.697 pg/uL) formula.
Lactobacilli colonized the oral cavity of breastfed infants significantly more frequently than formula-fed infants. The dominant Lactobacillus was L. gasseri, which was detected at higher levels in breastfed than formula-fed infants and displayed probiotic traits in vitro.
乳杆菌属可以对整体和口腔健康产生积极影响，并且经常在婴儿期通过母乳喂养获得。本研究旨在鉴定母乳喂养和配方奶喂养的 4 个月大婴儿口腔中的乳杆菌属，并评估所检测到的优势乳杆菌属的潜在益生菌特性。从 133 名参加一项纵向研究（n=240）的婴儿中收集唾液和口腔拭子样本，该研究旨在研究一种新的婴儿配方对儿童生长和发育的影响。从 16S rRNA 基因序列中培养并鉴定了唾液中的乳杆菌属分离株。对 5 种 16S rRNA 序列不同的 L. gasseri 分离株进行了抑制选定口腔细菌生长和黏附口腔组织的能力测试。通过 qPCR 分析口腔拭子样本中的 L. gasseri。
43 名（32.3%）婴儿为母乳喂养，90 名（67.7%）婴儿为配方奶喂养，其中 90 名婴儿中有 43 名（47.8%）为标准配方奶喂养，47 名（52.2%）为添加了乳脂肪球膜（MFGM）的配方奶喂养。34.1%的母乳喂养婴儿的唾液中可培养出乳杆菌属，但仅在 4.7%的标准配方奶喂养婴儿和 9.3%的添加 MFGM 的配方奶喂养婴儿中可培养出乳杆菌属。在所检测的六种乳杆菌属中，L. gasseri 是最常见的（88%的乳杆菌属阳性婴儿）。L. gasseri 分离株抑制了变异链球菌结合唾液包被的羟基磷灰石，并以浓度依赖的方式抑制了变异链球菌、唾液链球菌、奈瑟氏放线菌、口腔奈瑟氏菌、白色念珠菌和具核梭杆菌的生长。L. gasseri 分离株结合到腮腺和颌下腺唾液、唾液 gp340 和 MUC7、以及纯化的 MFGM，并黏附到上皮细胞上。qPCR 检测到 29.7%的口腔拭子中存在 L. gasseri。与标准配方奶（0.363 pg/μL）或 MFGM 配方奶（0.697 pg/μL）喂养的婴儿相比，母乳喂养的婴儿口腔中 L. gasseri 的平均 DNA 水平显著更高（2.14 pg/μL）。
与配方奶喂养的婴儿相比，乳杆菌属更频繁地定植于母乳喂养婴儿的口腔。优势乳杆菌属是 L. gasseri，在母乳喂养婴儿中的检出率高于配方奶喂养婴儿，并且在体外具有益生菌特性。
