《食品工业科技》F5000论文展播：百合多糖的纯化及其对肠道菌群失调小鼠的调节作用（2022年）

Objectives:The gut microbiota can regulate intestinal movement and secretion, decompose macromolecular complex polysaccharides in food, participate in the digestion and absorption of nutrients, promote and maintain the normal development and activity of the immune system. At present, the most commonly used drugs for treating intestinal microbiota imbalance are antibiotics. With the widespread application of antibiotics in clinical practice, they not only kill pathogenic bacteria but also affect the normal microbiota. Therefore, people are beginning to search for natural substances with microecological regulatory effects for research. Lily not only contains rich nutrients such as starch, protein, and trace elements, but also contains various bioactive components such as polysaccharides, alkaloids, saponins, etc. With the development of microecology, microecology theories and methods have been introduced into the study of traditional Chinese medicine. Modern research has shown that plant polysaccharides can promote intestinal mucosal immune levels, regulate intestinal microbiota, and promote healthy intestinal development. Therefore, this article purifies lily polysaccharides and explored their regulatory effects on intestinal microbiota imbalance in mice. 

Methods:This article first used traditional Chinese medicine lilies as raw materials and used ultrasound assisted water extraction to extract lily polysaccharides. The purification effects of AB-8, D315, D101, and HPD-100 macroporous resins on lily polysaccharides were compared using decolorization rate, yield, and polysaccharide content as indicators, and the most suitable macroporous resin is selected. Subsequently, a mouse model was established by gavage of 10 mg/kg lincomycin hydrochloride. 60 healthy Kunming mice were divided into blank (saline 10 mg/kg), model (lincomycin hydrochloride 10 mg/kg), positive (lizhu intestine 10 mg/kg), and low, medium, and high (50, 100, 200 mg/kg) dose groups of lily polysaccharides. Using transmission electron microscopy to observe the pathological specimens of mouse intestinal mucosa, and the lipopolysaccharide (LPS), serum inflammatory factors IL-6, TNF-α and intestinal tissue SIgA, as well as the number of bacteria were used as indicators to evaluate the regulatory effect of purified lily polysaccharides on intestinal microbiota imbalance in mice.

Results:The purification effect of D315 was the best, with the highest decolorization rate, purification yield, and polysaccharide content of lily polysaccharides after purification, which were 35.11%±1.12%, 40.82%±1.28%, and 82.56%±1.18%, respectively. The transmission electron microscopy results showed that compared with the model group, the intestinal mucosal villi of the low-dose polysaccharide group mice were occasionally loose, but the state was restored compared to the model group. The intestinal mucosal villi of the medium and high-dose polysaccharide groups mice were arranged neatly without breakage, and basically recovered to the same state as the blank group. Among them, the high-dose polysaccharide group of lily had the best effect. The pharmacological experimental results showed that compared with the model group, the LPS content, serum inflammatory factors IL-6 and TNF-α levels in the high dose group were significantly decreased, and the ileal tissue SIgA content was significantly increased (P<0.01), the number of Enterobacteriaceae and Enterococcus were reduced, while the number of Lactobacillus and Bifidobacteria were increased (P<0.05). In summary, the lily polysaccharide would have a regulatory effect on the intestinal flora disorder in mice.

Conclusion: This article used the content of SIgA and LPS in mouse ileum tissue, the content of serum inflammatory factors IL-6 and TNF-α, and the number of bacterial communities as evaluation indicators to study the regulatory effect of purified lily polysaccharides on intestinal microbiota imbalance in mice. Results showd that lily polysaccharides might inhibit the increase of LPS, IL-6, and TNF-α content, thereby inhibiting the release of inflammatory factors in cells, increasing the content of SIgA, and regulating intestinal microbiota imbalance by cultivating beneficial and inhibiting harmful bacteria in the intestine. In the future, the clinical use and further development of lily polysaccharide microecological modulators would be explored based on the mechanism of regulation of gastrointestinal microbiota by lily polysaccharide.