Preparation of Lycium barbarum oligosaccharides using microwave-assisted FeCl3-DES system: Efficacy, physicochemical characteristics, and probiotic effects.

Abstract

The inability to efficiently degrade high molecular weight plant polysaccharides has limited the application of functional oligosaccharides. This study introduces a novel approach using microwave-assisted Lewis acid degradation to transform Lycium barbarum polysaccharides (129.8 kDa) into oligosaccharides (5.0 kDa) within 20 min, achieving a degradation rate of 96%. The incorporation of deep eutectic solvents (DES) significantly reduces the formation of furfurals and dicarbonyl compounds by 43.2% and effectively suppresses the production of advanced glycation end products (AGEs). The resulting oligosaccharides exhibit a linear structure, low viscosity, and a liquid state, offering enhanced antioxidant and probiotic properties. They can double the count of lactobacilli and increase the concentration of short-chain fatty acids by 1.5 times. Most notably, they provide robust cryoprotective effects for probiotics. This research lays a solid technical foundation for the degradation of plant polysaccharides, paving the way for their broader applications in the food and pharmaceutical industries.