Colonic SCFA Uptake: 2D Diffusion-Reaction Concentration Profile

Gut bacteria ferment dietary fibre into short-chain fatty acids such as butyrate, propionate and acetate — but getting those molecules out of the colonic lumen and into the body depends on chemistry, not just production. This simulator solves a live 1D reaction-diffusion model of the colonic epithelium: total SCFA concentration diffuses across a spatial grid toward the membrane, splits into protonated and deprotonated fractions according to the Henderson–Hasselbalch equilibrium, and crosses either by unsaturable passive diffusion or through a saturable, Michaelis–Menten-governed MCT1 transporter — rendered as a live concentration-profile chart and a scrolling flux strip chart rather than a 3D particle scene. Adjust luminal pH, SCFA supply concentration and transporter density to see how the two absorption pathways trade off, with live readouts for ionization fraction, passive flux, transporter flux and carrier saturation.