Profiling of the microbiota of breast milk before and after feeding with an artificial nipple

• Published in: Journal of oral biosciences Vol. 64; no. 4; pp. 431 - 436
• Main Authors: Sano, Hiroto, Wakui, Anna, Kawachi, Miho, Maruyama, Shingo, Moriyama, Sachie, Nishikata, Mayumi, Washio, Jumpei, Abiko, Yuki, Mayanagi, Gen, Sakashita, Reiko, Tanaka, Kaori, Takahashi, Nobuhiro, Sato, Takuichi
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.12.2022
• Subjects: Bacteria - genetics; Bottle feeding; Breast feeding; Female; Humans; Infant; Microbiology; Microbiota; Microbiota - genetics; Milk, Human - microbiology; Nipples; RNA, Ribosomal, 16S - genetics; Streptococcus - genetics; Bottle feeding; Microbiota; Microbiology; Breast feeding
• ISSN: 1349-0079; 1880-3865
• DOI: 10.1016/j.job.2022.09.004

Breast milk is a valuable and useful source of nutrition; however, surplus milk is routinely discarded for hygiene reasons despite an unclear scientific basis. Here, we profiled the microbiota of expressed breast milk before and after feeding with an artificial nipple and examined the bacterial survival in breast milk stored at 4 °C. Eleven mother–baby pairs were included in the study. Samples of expressed breast milk were collected before and after feeding with an artificial nipple and examined both immediately (0 h) and after storage for 3 and 12 h at 4 °C. Each sample was inoculated onto a blood agar plate and incubated anaerobically and aerobically at 37 °C. Genomic DNA was extracted from individual bacterial colonies, which were identified by 16S rRNA gene sequencing. Before feeding, the bacterial counts at 0 and 12 h were (1.4 ± 1.6) × 105 colony-forming units (CFU)/mL and (1.4 ± 0.6) × 105 CFU/mL, respectively. Staphylococcus (47.7% and 41.9%, respectively), Cutibacterium (20.7% and 36.0%, respectively), and Streptococcus (16.1% and 6.6%, respectively) were identified among the samples. In contrast, after feeding, the bacterial counts at 0 and 12 h were (2.7 ± 1.7) × 105 CFU/mL and (2.1 ± 2.5) × 105 CFU/mL, respectively. Staphylococcus (30.1% and 37.4%, respectively), Cutibacterium (11.7% and 31.7%, respectively), and Streptococcus (41.5% and 25.2%, respectively), were identified among the samples. Bacteria were present in the breast milk before feeding. Although the main component of the microbiota shifted from Staphylococcus to Streptococcus species after feeding, these results suggest that surplus expressed breast milk may be preserved safely in a refrigerator for at least 12 h after feeding with an artificial nipple. [Display omitted] •More than 104 cells/mL of bacteria were found in the expressed breast milk before feeding.•The microbiota consists mainly of Staphylococcus, Cutibacterium, and Streptococcus species.•The main bacteria shifted from Staphylococcus to Streptococcus species after feeding.•Surplus expressed breast milk can be preserved safely in a refrigerator for 12 h after feeding.