Combinations of bacterial probiotics and yeast postbiotics influence fat deposition and growth in the nematode C. elegans

Probiotics are live microorganisms with intended benefits on human health including obesity. As a small and fast-growing whole organism model, Caenorhabditis elegans has been used to assess the health effects of probiotics where mechanisms can be assessed through available genetic tools. Results from C. elegans can provide data on the effect of specific probiotic strains and combinations with prebiotics and postbiotics on health-related physiology to inform selections of interventions for further study. We hypothesized that specific combinations with prebiotics and postbiotics could both speed up worm development and reduce fat deposition, suggesting they allow for more effective nutrient utilization. Here we expose C. elegans to the ABB S20 strain of Lactiplantibacillus plantarum in combination with different prebiotics and postbiotics. We then measure how these affect growth and development speed as well as fat deposition by measuring the time until the appearance of progeny and measuring Oil Red O staining respectively. Our results show that the combination of probiotic L. plantarum ABB S20 plus the postbiotic inactive yeasts K. marxianus ABB S8 and S. boulardii ABB S3 resulted in fast growth and reduced fat deposition compared to L. plantarum ABB S20 alone. These results demonstrate the usefulness of C. elegans as a model to efficiently screen though combinations of probiotics, prebiotics and postbiotics to find those that are candidates to help with effective nutrition use and therefore weight management. Using Lactiplantibacillus plantarum ABB S20 as a food source, we performed a screen of combinations with prebiotics and postbiotics to find a combination that results in speeded up C. elegans development and reduced fat deposition, thereby suggesting more effective nutrient utilization. • A screen of combinations with prebiotics and postbiotics. • Adding two postbiotics, resulted in speeded up C. elegans development and reduced fat deposition. • Yeast postbiotics and bacterial probiotics combine to influence fat deposition and growth. • C. elegans can provide data to inform selections for further study in more complex systems.