Molecular microbiological profiling of bottled unsweetened tea beverages: A screening experiment.

To explore the potential storage and safety of drinking leftover bottled tea beverages from various manufacturers after direct drinking from bottles, we conducted a screening experiment on the growth of salivary bacteria in plastic bottles of tea. The diluted saliva samples from 10 participants were inoculated into the test bottled beverages, which resulted in bacteria, particularly former members of the genus Lactobacillus, growing in some green tea beverages with a neutral pH. In contrast, tea beverages with less bacterial growth contained Streptococcus spp., and the leftovers may be safe to store and drink again.

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

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.

Microbiota profiles on the surface of non-woven fabric masks after wearing.

This study aimed to characterize commensal microbiota on the skin before and after wearing masks, and to characterize the microbiota on the surface of used masks after 1 week of drying. From the 13 human subjects (age range, 19-26 years), mean bacterial concentrations of (6.1 ± 11.0) × 105 and (1.0 ± 1.4) × 106 colony-forming units (CFU)/mL were recovered from the skin of the buccal areas wiped with a sterile cotton swab before and after wearing non-woven fabric masks for 8 h, respectively. Furthermore (3.4 ± 4.9) × 104 CFU/mL of bacteria were recovered from the mask surfaces. The bacteria contained in the masks, which consisted mainly of Cutibacterium acnes and Staphylococcus epidermidis/aureus, virtually disappeared after drying the masks indoors for 1 week.