Impacting Colonic Microbiota Trajectories through Food Structures: Can Chitin from Edible Crickets or Amyloid-Like Fibrils Act as Novel Prebiotics?

Processed foods and alternative food sources have been at the heart significant debate due to their intersections with human health and wellbeing. This work will overview the main findings of two published studies seeking to elucidate the unchartered digestive fate of chitin or proteinaceous nano-architectures that may form during food processing. Results of these studies will first demonstrate evidence from anaerobic human fecal fermentations (n=10 healthy volunteers) of powders from crickets (Acheta domestica), silkworm pupae (Bombyx mori) or isolated chitin structures. Findings suggest chitin significantly (p<0.05) supports biodiversity measures (e.g., alpha diversity) and may stimulate symbionts like members of the Ruminococcaceae and Lachnospiraceae families and the genera Faecalibacterium and Roseburia. Secondly, processing will be shown to induce fibrilization of whey and egg proteins into amyloid-like fibrils. In turn, fibrils or their progenitor proteins were fed to colonic models followed by 16S rRNA gene sequencing and bioinformatic analysis using QIIME2. These show fibrilization preserves colonic microbial diversity, low Firmicutes/Bacteroidetes ratio and protect butyrate producing genera, namely Roseburia and Clostridium, similarly to prebiotic fructooligosaccharides. In addition, PICRUSt2 in silico metabolic pathway predictions support that fibrils divert microbiota metabolic trajectories towards those observed in fermentation of prebiotics. Thus, this work will raise the question whether food processing can help fabricate ingredients with macromolecular assemblies that divert human colonic microbiota with relevance to food safety and wholesomeness.