Extraction and characterization of polysaccharides from Schisandra sphenanthera fruit by Lactobacillus plantarum CICC 23121-assisted fermentation

Improving the yield of polysaccharides extracted from Schisandra sphenanthera is a major challenge in traditional Chinese medicinal plants. In this study, we investigated the potential of Lactobacillus plantarum CICC 23121-assisted fermentation as an extraction tool for S. sphenanthera polysaccharides (SSP). We observed that 11.12 ± 0.28 % of polysaccharides were extracted from S. sphenanthera using strain CICC 23121 -assisted fermentation (F-SSP), which was 53.38 % higher than that using hot water extraction (NF-SSP). The optimized parameters were a fermentation time of 15.5 h, substrate concentration of 4 %, and inoculum size of 3 %. Lactic acid produced by strain CICC 23121 increased the release of intracellular polysaccharides by breaking down cell walls. Compared to NF-SSP, F-SSP contained higher and lower total carbohydrate and protein contents, respectively, and its monosaccharide composition was the same as that of NF-SSP; however, their distributions were different. F-SSP had a higher molecular weight, better aqueous stability, and looser surface morphology, and strain CICC 23121-assisted fermentation did not change the molecular structure of SSP. Both NF-SSP and F-SSP showed the potential to regulate human intestinal microflora. Our findings revealed that strain CICC 23121-assisted fermentation is an efficient method for extracting S. sphenanthera polysaccharides without affecting their physicochemical and bioactive properties.