Non-nutritive sweeteners (NNSs) are popular sugar substitutes, valued for their potential to reduce caloric intake and associated health risks. However, their long-term effects on the human gut microbiome remain debatable. This study investigates the impact of tagatose, allulose, Rebaudioside-A (Reb-A), and saccharin on quorum-sensing (QS)-regulated phenotypes and gene expression in QS biosensor model bacteria. It sheds light on their potential influence on the gut microbiome. Our study revealed diverse effects among the NNSs. Tagatose and allulose demonstrated QS phenotypic inhibition in Chromobacterium violaceum (≈50%) and Pseudomonas aeruginosa (20–50%) in a concentration-dependent manner. Additionally, tagatose and allulose decreased the P. aeruginosa lasI gene expression. Reb-A and saccharin presented a significant, however less prominent, phenotypic inhibition on C. violaceum (25–30%) and P. aeruginosa swarming motility (≈20%). Both NNSs decreased the expression of the lasI gene of P. aeruginosa. Molecular docking of QS regulatory proteins showed that saccharin and Reb-A have significantly higher binding affinity compared to allulose and tagatose, relative to native inducers. These results suggest the complex interactions mediated by NNSs in QS regulatory pathways. These findings provide valuable insights into the varied, species and dose-dependent effects of NNS on microbial communication, suggesting potential implications for the gut microbiome.

Fast radio burst (FRB) science primarily revolves around two facets: the origin of these bursts and their use in cosmological studies. This work follows from previous redshift–dispersion measure (z–DM) analyses in which we model instrumental biases and simultaneously fit population parameters and cosmological parameters to the observed population of FRBs. This sheds light on both the progenitors of FRBs and cosmological questions. Previously, we have completed similar analyses with data from the Australian Square Kilometer Array Pathfinder (ASKAP) and the Murriyang (Parkes) Multibeam system. In this manuscript, we use 119 FRBs with 29 associated redshifts by additionally modelling the Deep Synoptic Array (DSA) and the Five-hundred-metre Aperture Spherical radio Telescope (FAST). We also invoke a Markov chain Monte Carlo (MCMC) sampler and implement uncertainty in the Galactic DM contributions. The latter leads to larger uncertainties in derived model parameters than previous estimates despite the additional data and indicate that precise measurements of DM$_\textrm{ISM}$ will be important in the future. We provide refined constraints on FRB population parameters and derive a new constraint on the minimum FRB energy of log $E_{\mathrm{min}}$(erg)=39.47$^{+0.54}_{-1.28}$ which is significantly higher than bursts detected from strong repeaters. This result likely indicates a low-energy turnover in the luminosity function or may alternatively suggest that strong repeaters have a different luminosity function to single bursts. We also predict that FAST will detect 25–41% of their FRBs at $z \gtrsim 2$ and DSA will detect 2–12% of their FRBs at $z \gtrsim 1$.