Furcellaran nanocomposite films: The effect of nanofillers on the structural, thermal, mechanical and antimicrobial properties of biopolymer films.

Graphene oxide (GO) and multi-walled carbon nanotubes (MWCNTs) were added to furcellaran films (FUR). Silver nanoparticles (AgNPs) were prepared by reducing AgNO3 using a FUR matrix as the stabilising agent. The structure and surface morphology of nanocomposite films were obtained using FTIR, SEM and XRD. The molecular weights of furcellaran chains were estimated using HPSEC-MALLS-RI. Characterisation of the films was undertaken to analyse their physical, mechanical and structural properties. SEM analysis revealed that GO, MWCNTs and AgNPs were evenly distributed throughout the FUR surface. FUR + AgNP films showed antimicrobial activity against bacteria and fungi. P. aeruginosa, E. faecalis and S. aureus were the most affected with effective growth inhibition using the disc diffusion method. In the study, the effect of nanofillers on the structural, thermal, mechanical and antimicrobial properties of furcellaran films as potential materials for food packaging is presented.

Differences in Sweet Taste Perception and Its Association with the Streptococcus mutans Cariogenic Profile in Preschool Children with Caries.

The aim of the study was to verify the hypothesis about differences in sweet taste perception in the group of preschool children with and without caries, and to determine its relationship with cariogenic microbiota and the frequency of sweets consumption in children. The study group included of 63 children aged 2-6 years: 32 with caries and 31 without caries. The study consisted of collecting questionnaire data and assessment of dental status using the decayed, missing, filled in primary teeth index (dmft) and the International Caries Detection and Assessment System (ICDAS II). The evaluation of sweet taste perception was carried out using a specific method that simultaneously assessed the level of taste preferences and the sensitivity threshold for a given taste. The microbiological analysis consisted of the assessment of the quantitative and qualitative compositions of the oral microbiota of the examined children. The sweet taste perception of children with caries was characterized by a lower susceptibility to sucrose (the preferred sucrose solution concentration was >4 g/L) compared to children without caries (in the range ≤ 4 g/L, p = 0.0015, chi-square test). A similar relationship was also observed for frequent snacking between meals (p = 0.0038, chi-square test). The analysis of studied variables showed the existence of a strong positive correlation between the perception of sweet taste and the occurrence and intensity of the cariogenic process (p = 0.007 for dmft; and p = 0.012 for ICDAS II), as well as the frequency of consuming sweets (p ≤ 0.001 for frequent and repeated consumption of sweets during the day, Spearman test) in children with caries. Additionally, children with an elevated sucrose taste threshold were more than 10-times more likely to develop S. mutans presence (OR = 10.21; 95% CI 3.11-33.44). The results of this study suggest the future use of taste preferences in children as a diagnostic tool for the early detection of increased susceptibility to caries through microbial dysbiosis towards specific species of microorganisms.