Researchers Convert Plant-Based Food Waste into Potential Prebiotics Using Enzymatic Process
Scientists used a bacterial enzyme to chemically modify raffinose family oligosaccharides (RFOs) — compounds found in legumes that cause bloating and digestive discomfort — into new mixed-linkage galactooligosaccharides with prebiotic potential. RFOs are increasingly abundant as food industry side streams grow alongside the global shift toward plant-based diets. The findings suggest a way to simultaneously reduce food waste and produce functional prebiotic ingredients from materials currently considered problematic.
Raffinose family oligosaccharides (RFOs), common in legumes and plant-based food production side streams, are known to cause gastrointestinal symptoms such as nausea, bloating, and diarrhoea, drawing comparisons to lactose intolerance. Researchers employed a β-galactosidase enzyme from the bacterium Niallia circulans to perform transglycosylation reactions using RFOs as acceptors and lactose as a sugar donor, producing novel RFO-based β-GOS (galactooligosaccharides). NMR characterization confirmed that the primary product featured β(1-4) galactosylation at the non-reducing galactose end of the RFO molecules, and these new compounds constituted the largest fraction by weight in the reaction mixture. A microbial screening of 11 gut and food-relevant bacterial strains showed that the beneficial gut bacterium Bacteroides ovatus could metabolize the modified oligosaccharides for growth, while other strains required adaptation or could not use them at all — indicating reduced fermentability compared to unmodified raffinose. The study positions this enzymatic approach as a promising strategy for upgrading plant-based food industry side streams into value-added prebiotic ingredients, aligning with broader goals of functional food development and food waste reduction.
What's missing
The study is a preprint and has not yet undergone peer review. Key limitations include the in vitro nature of the microbial screening, which does not replicate the complexity of the human gut microbiome; the absence of in vivo or clinical data on safety, tolerability, or actual prebiotic efficacy in humans; and uncertainty about whether the reduced fermentability observed in some strains would translate to reduced gastrointestinal symptoms in consumers. The scalability and cost-effectiveness of the enzymatic process at industrial scale is also not addressed.
What different sources said
- bioRxivCenter
From FODMAPs to prebiotic candidates: enzymatic transglycosylation of raffinose oligosaccharides towards new mixed-linkage oligosaccharides
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