Project description:Annona muricata L., include the leaves, is found to contain biologically active Annonaceous acetogenins and plant polyphenols that are important components of human diet and a number of them are considered to have chemopreventive and therapeutic properties against cancer.
To confirm previous findings in in vitro, animal study and traditionally use, a human, ex vivo and in vitro studies were conducted to evaluate the effects of consecutive ingestion of A. muricata leaves extract for eight weeks.
Project description:we report that succinate, a metabolite abundantly produced by the dysbiotic gut microbiota, induces in vitro biofilm formation of C. difficile strains. We characterized the morphology and spatial composition of succinate- induced biofilms, and compared to non-induced or deoxycholate-induced biofilms, biofilms induced by succinate are significantly thicker, structurally more complex, and poorer in proteins and exopolysaccharides (EPS).
Project description:investigate the effects of salivary histatin 5 (Hst5) on Porphyromonas gingivalis (P. gingivalis) biofilms in vitro and in vivo and the possible mechanisms.
Project description:Within the mouth bacteria are starved of saccharides as their main nutrient source between meals and it is unclear what drives their metabolism. Previously oral in vitro biofilms grown in saliva have shown proteolytic degradation of salivary proteins and increased extracellular proline. Although arginine and glucose have been shown before to have an effect on oral biofilm growth and activity, there is limited evidence for proline. Nuclear magnetic resonance (NMR) spectroscopy was used to identify extracellular metabolites produced by bacteria in oral biofilms grown on hydroxyapatite discs. Biofilms were inoculated with whole mouth saliva and then grown for 7 days using sterilised whole mouth saliva supplemented with proline, arginine and glucose as a growth-medium. Overall proline had a beneficial effect on biofilm growth – with significantly fewer dead bacteria present by biomass and surface area of the biofilms (p <0.05). Where arginine and glucose significantly increased and decreased pH, respectively, the pH of proline supplemented biofilms remained neutral at pH 7.3-7.5. SDS-polyacrylamide gel electrophoresis of the spent saliva from proline and arginine supplemented biofilms showed inhibition of salivary protein degradation of immature biofilms. NMR analysis of the spent saliva revealed that proline supplemented biofilms were metabolically similar to unsupplemented biofilms, but these biofilms actively metabolised proline to 5-aminopentanoate, butyrate and propionate, and actively utilised glycine. This study shows that in a nutrient limited environment, proline has a beneficial effect on in vitro oral biofilms grown from a saliva inoculum.