Assessment of bacterial diversity in breast milk using culture-dependent and culture-independent approaches

Abstract

Initial neonatal gut colonisation is a crucial stage for developing a healthy physiology, beneficially influenced by breast-feeding. Breast milk has been shown not only to provide nutrients and bioactive/immunological compounds, but also commensal bacteria, including gut-associated anaerobic Bifidobacterium spp. The aim of the present study was to investigate bacterial diversity in breast milk, with emphasis on identifying gut-associated obligate anaerobes. Breast milk collected from seven mothers at three sampling points (days 3-6, 9 -14 and 25 -30 postpartum) was analysed by combined culture-dependent and state-of-the-art, culture-independent methods (Sanger sequencing and 454-pyrosequencing). In addition to the predominance of facultative anaerobes such as Staphylococcus, Streptococcus and Propionibacterium (.90 % of isolated strains and 23·7 % relative abundance using pyrosequencing), significant populations of obligate anaerobes, including Bifidobacterium and Veillonella, were detected using pyrosequencing and confirmed by the isolation of viable strains (3·4 % of isolates and 1·4 % relative abundance). Pyrosequencing also revealed the presence of DNA of multiple major gut-associated obligate anaerobes (6·2 % relative abundance) such as Bacteroides and, for the first time, several members of the Clostridia, including butyrate producers, such as Faecalibacterium and Roseburia, which are important for colonic health. The present study suggests that breast milk may be a major source of bacterial diversity to the neonatal gut, including gut-associated obligate anaerobes, and may thus significantly influence gut colonisation and maturation of the immune system.

Gut microbiota: a source of novel tools to reduce the risk of human disease?

“…Recently, more attention has been given to differences in early microbial contact related to the mode of birth. An accumulating body of evidence indicates that vaginally and surgically delivered neonates exhibit distinct gut colonization patterns (6,7,33,44,45). The differences in gut microbiota composition may still be observed at the age of 7 y (46).…”

Reshaping the Gut Microbiota at an Early Age: Functional Impact on Obesity Risk?

“…stimulated by fermentation of nondigestible oligosaccharides found also in breast milk. It is well established that a gut microbiota dominated by Bifidobacteria typifies that of the healthy breastfed infant [22], breastfed infants harboring twice as many Bifidobacterium cells compared to formula-fed infants [23]. On the other hand, formula-fed neonates are likely to harbor a more diverse microbiota including Enterobacteriaceae, Enterococcus and, as recently demonstrated, also Bacteroides [23,24,25].…”

Effect of intestinal microbiome in norm and pathology on human health

“…Наличие Bifidobacteria и Lactobacillus в грудном молоке имеет важное значение в процессе колонизации, поскольку данные микроорганиз-мы ответственны за активацию клеток, продуцирующих IgA в кишечнике в неонатальном периоде. Bifidobacteria доминируют в составе кишечной микрофлоры у младен-цев, находящихся на исключительно на грудном вскармли-вании [18], при этом их количество почти в 2 раза превы-шает содержание аналогичных представителей у искус-ственно вскармливаемых детей [19]. Sjögren с соавт.…”