An in vitro study of the effects of Phellodendron bark extract and berberine chloride on periodontal pathogenic bacteria in the oral microbiome.

OBJECTIVES: Periodontal disease is triggered by oral microbiome dysbiosis. Thus, to prevent its onset, it is important to maintain relative abundance of periodontal pathogenic bacteria in the oral microbiome at a low level. While Phellodendron bark extract (PBE) and its active ingredient, berberine, exert antibacterial effects on periodontal pathogenic bacteria, such as Porphyromonas gingivalis, their effects on the oral microbiome as a whole remain unknown. Therefore, we aimed to clarify the potential of PBE and berberine chloride (BC) in regulating the relative abundance of periodontal pathogenic bacteria in the oral microbiome. METHODS: Saliva was collected from 20 participants. Each participant's saliva was combined separately with P. gingivalis suspension and either PBE or BC in a modified basal medium. The samples were then incubated under anaerobic conditions for 24 h. After cultivation, we determined the total bacterial concentration using quantitative polymerase chain reaction analysis and the bacterial composition using 16 S ribosomal RNA gene sequencing. RESULTS: The total bacterial concentration was reduced because of treatment with PBE and BC. Bacterial 16 S ribosomal RNA gene sequencing confirmed that treatment with PBE and BC significantly reduced the relative abundance of periodontal pathogenic bacteria, including red and orange complex bacteria. CONCLUSIONS: Our findings suggest that PBE and BC reduce the relative abundance of periodontal pathogenic bacteria in the oral microbiome. Thus, PBE and BC can aid in preventing periodontal disease, given their ability to regulate the oral microbiome composition and their anti-inflammatory effects.

Reduction of saliva-derived droplet diffusion by mouth-closed tooth brushing in the era of COVID-19.

PURPOSE: To clarify the effect of mouth-closed tooth brushing on the suppression of droplet generation in comparison with ordinary (mouth-open) tooth brushing and to investigate the difference in plaque removal efficacy between mouth-open and mouth-closed tooth brushing. METHODS: Fourteen adults participated in the study. The labial/buccal, lingual, and occlusal surfaces of each sextant were brushed with the mouth open and closed, and a high-sensitivity camera and a high-power light source were used to measure the number of generated droplets. The plaque removal efficacy of each type of tooth brushing was evaluated according to the O'Leary Plaque Control Record. RESULTS: Significantly more droplets were generated by mouth-open brushing than by mouth-closed brushing. The number of droplets was highest when the lingual surfaces of the upper anterior sextants were brushed with the mouth open. In mouth-closed brushing, almost no droplets were observed from any region. The plaque removal rate with each type of brushing did not differ significantly among any regions except the lingual surfaces of the upper left sextant. CONCLUSION: Mouth-closed tooth brushing almost completely suppressed droplet generation and did not reduce the plaque removal efficacy. Therefore, mouth-closed tooth brushing is beneficial as an oral hygiene method during coronavirus disease 2019 outbreaks.

Crystallization and preliminary X-ray crystallographic analysis of UDP-glucuronic acid:flavonol-3-O-glucuronosyltransferase (VvGT5) from the grapevine Vitis vinifera.

Grapevine (Vitis vinifera) glycosyltransferase 5 (VvGT5) is a UDP-glucuronic acid:flavonol-3-O-glucuronosyltransferase that catalyses the 3-O-specific glucuronosylation of flavonols using UDP-glucuronic acid as a sugar donor to produce flavonol 3-O-glucosides, which are important bioactive phytochemicals. Recombinant VvGT5 expressed in Escherichia coli cells was purified and crystallized by the sitting-drop vapour-diffusion method. A full set of X-ray diffraction data was collected to 2.2 ŠBragg spacing from a single crystal using a synchrotron-radiation source. The crystal was hexagonal, belonging to space group P6(1)22, with unit-cell parameters a = b = 102.70, c = 535.92 Å. The initial phases were determined by the molecular-replacement method.