Profiling of the microbiota in the remaining sports drink and orange juice in plastic bottles after direct drinking

Abstract

Objectives: The survival of bacteria in the sports drink and orange juice remaining in and at the mouth of bottles after direct drinking was examined after immediately drinking and incubation at 37 °C for 24 h.

Methods: Nine healthy participants were asked to drink approximately 100 mL of a plastic bottled sports drink or orange juice. The samples were cultured anaerobically at 37 °C for 7 days. Genomic DNA was extracted from the resulting individual colonies, and bacterial species were identified using 16 S rRNA gene sequencing.

Results: The mean amount of bacteria in the remaining sports drink and orange juice, immediately after drinking, were (1.6 ± 2.3) × 10³ colony-forming units (CFU)/mL and (2.9 ± 3.3) × 10³ CFU/mL, respectively. Additionally, bacteria recovered from the mouths of the sports drink and orange juice bottles were (2.5 ± 5.5) × 10⁴ CFU/mL and (5.8 ± 2.4) × 10³ CFU/mL, respectively. Oral bacteria, such as Streptococcus, Actinomyces, Neisseria, and Rothia were found to be transferred in the sports drink and orange juice, and the bacteria were scarcely detected after incubation at 37 °C for 24 h.

Conclusions: The bacterial levels differed significantly from the previously reported levels in bottled tea 24 h after drinking, suggesting that remaining drinks with low pH levels can be preserved for a longer period.

Keywords: Microbiota; Orange juice; Sport-drink.