Human Milk Oligosaccharides Exhibit Biofilm Eradication Activity Against Matured Biofilms Formed by Different Pathogen Species

Abstract

Human milk oligosaccharides (HMOs) have been shown to exhibit plenty of benefits for infants, such as prebiotic activity shaping the gut microbiota and immunomodulatory and anti-inflammatory activity. For some pathogenic bacteria, antimicrobial activity has been proved, but most studies focus on group B streptococci. In the present study, we investigated the antimicrobial and antibiofilm activities of the total and fractionated HMOs from pooled human milk against four common human pathogenic Gram-negative species (Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Burkholderia cenocepacia) and three Gram-positive species (Staphylococcus aureus, Enterococcus faecium, and Enterococcus faecalis). The activity of HMOs against enterococci and B. cenocepacia are addressed here for the first time. We showed that HMOs exhibit a predominant activity against the Gram-positive species, with E. faecalis being the most sensitive to the HMOs, both in planktonic bacteria and in biofilms. In further tests, we could exclude fucosyllactose as the antibacterial component. The biological significance of these findings may lie in the prevention of skin infections of the mother’s breast as a consequence of breastfeeding-induced skin laceration and/or protection of the infants’ nasopharynx and lung from respiratory pathogens such as staphylococci.

Residents or Tourists: Is the Lactating Mammary Gland Colonized by Residential Microbiota?

“…HMOs can inhibit the adhesion of pathogens by acting as decoy receptors that bind harmful bacteria, including Pseudomonas aeruginosa, Salmonella enterica, and enteropathogenic Escherichia coli [43]. One study found that HMOs isolated from milk samples of nine healthy participants could suppress the growth of Staphylococcus aureus, Enterococcus faecium, and Enterococcus faecalis, regardless of whether the bacteria were planktonic or in biofilms [44]. HMOs also have the ability to enhance cytokine secretion in vitro [45].…”

Prebiotics in New-Born and Children’s Health

“…Recent research has suggested that prebiotic HMOs may improve the ability of beneficial microbiota to adhere to an infant's gastrointestinal wall by modulating the expression of bacterial adhesins [57][58][59]. Microbial contact, known as adhesion, occurs between the surface components of bacterial cells entering an infant's gut, such as lactobacilli, and the surfaces of the host's digestive tract.…”

Overview of Breastfeeding Under COVID-19 Pandemic

“…HMO inhibits the activity of norovirus, rotavirus, and influenza virus by balancing cytokine response, stimulating the maturation of epithelial cells, and reducing viral adherence to target cells ( 47 ). It can also inhibit many Gram-negative pathogenic bacteria such as Klebsiella pneumoniae , Acinetobacter baumannii , Pseudomonas aeruginosa , and Burkholderia cenocepacia , and many Gram-positive bacteria such as Staphylococcus aureus , Enterococcus faecium , and Enterococcus faecalis ( 52 ). Moreover, it has been demonstrated that Osteopontin can inhibit rotavirus infection in vivo , and glycerol monolaurate has been described to have a wide range of microbial inhibitory properties ( 47 ).…”