The effect of breastmilk and saliva combinations on the in vitro growth of oral pathogenic and commensal microorganisms

Abstract

Neonates are exposed to microbes in utero and at birth, thereby establishing their microbiota (healthy microbial colonisers). Previously, we reported significant differences in the neonatal oral microbiota of breast-fed and formula-fed babies after first discovering a primal metabolic mechanism that occurs when breastmilk (containing the enzyme xanthine oxidase) and neonatal saliva (containing highly elevated concentrations of the substrates for xanthine oxidase: xanthine and hypoxanthine). The interaction of neonatal saliva and breast milk releases antibacterial compounds including hydrogen peroxide, and regulates the growth of bacteria. Using a novel in vitro experimental approach, the current study compared the effects of this unique metabolic pathway on a range of bacterial species and determined the period of time that microbial growth was affected. We demonstrated that microbial growth was inhibited predominately, immediately and for up to 24 hr following breastmilk and saliva mixing; however, some microorganisms were able to recover and continue to grow following exposure to these micromolar amounts of hydrogen peroxide. Interestingly, growth inhibition was independent of whether the organisms possessed a catalase enzyme. This study further confirms that this is one mechanism that contributes to the significant differences in the neonatal oral microbiota of breast-fed and formula-fed babies.

Gut microbiota in ulcerative colitis: insights on pathogenesis and treatment

“…Sialylated milk oligosaccharides in breastmilk can promote the growth and development of infants by facilitating the proliferation of microflora . The synergistic interaction between breastmilk and saliva in the infant's mouth enhances innate immunity through the modulation of the oral microbiome . Thus, distinguishing between age‐related growth groups and clarifying the influence of the host and the environment on intestinal microflora is a therapeutic target to repair or prevent immaturity in intestinal microorganisms .…”

“…19 The synergistic interaction between breastmilk and saliva in the infant's mouth enhances innate immunity through the modulation of the oral microbiome. 20 Thus, distinguishing between age-related growth groups and clarifying the influence of the host and the environment on intestinal microflora is a therapeutic target to repair or prevent immaturity in intestinal microorganisms. 21 With relevance to the age onset, the microbiota begin to transform into their adult forms, which is considered to be relatively stable.…”

Racial and socioeconomic disparities in breast milk feedings in US neonatal intensive care units

“…46 Similarly, the interaction between MOM enzymes and the infant's saliva produce superoxide and hydrogen peroxide, which inhibit opportunistic pathogenic bacteria. 69 In the NICU, the routine use of MOM as oropharyngeal care may reduce the risk of ventilatorassociated pneumonia through multiple synergistic mechanisms, including this MOM−saliva interaction. 70 Thus, MOM is the consummate personalized medicine for all infants, especially premature VLBW infants.…”

Composition and maternal origin of the neonatal oral cavity microbiota

“…The contribution of maternal microbiota to early neonatal mouth colonization is currently not well understood. The neonatal oral microbiota is known to be shaped by exposures during and after delivery [2][3][4][5][6]. The mode of delivery has been suggested to have an impact on infants' oral and gut microbiota [7][8][9][10][11].…”