Optimization of fermentation conditions of oligosaccharide production from degradation of Polygonatum cyrtonema polysaccharides by Lactiplantibacillus plantarum and effect on probiotics growth

Although the probiotic functions of oligosaccharides and polysaccharides from Polygonatum cyrtonema have received extensive attention, the research on developing health-focused foods through the fermentation of P. cyrtonema using probiotics is still in the early stages. The P. cyrtonema was fermented by Lactiplantibacillus plantarum from different traditional fermented foods, the strain that could significantly promote the oligosaccharification of P. cyrtonema polysaccharides was screened, and the oligosaccharification fermentation conditions of P. cyrtonema polysaccharides were optimized by single-factor and response surface tests. The results showed that the oligosaccharification of P. cyrtonema polysaccharides could be significantly promoted by L. plantarum L5 as the fermentation strain. The optimal fermentation conditions for P. cyrtonema were as follows: fermentation time 5 d, fermentation temperature 35 ℃, and inoculum 4%. Under these optimal conditions, the contents of P. cyrtonema polysaccharides in fermentation broth was 21.81 mg/ml, which was 23.74% higher than before optimization. The test results of P. cyrtonema fermented freeze-dried powder on promoting probiotics growth showed that it could significantly promote the probiotics growth.