Analysis of the health-promoting effects of plant polysaccharides
Plant polysaccharides
Polysaccharides can be extracted from different types of plants, such as herbs, woody plants, shrubs and algae, as well as different parts of plants, such as roots, flowers, seeds, fruits, leaves and branches. The structural characteristics of polysaccharides are derived from their molecular weight, monosaccharide composition, branching properties and modified properties. Plant polysaccharides have a variety of active effects, such as antioxidant, anti-mutagenic, anti-aging, antibacterial and other effects. By analyzing plant polysaccharides from different sources, the mechanism of efficacy and activity is clarified, applied to the field of food industry, and further research and development of polysaccharide functional foods and health foods to promote human health.
Research results sharing
1. Lycium barbarum polysaccharides alleviate pancreatic β cell apoptosis by inhibiting the IFNγ pathway
Abstract
Lycium barbarum polysaccharides (LPB) alleviate pancreatic β cell apoptosis by inhibiting the IFN-γ pathway. Apoptosis-mediated pancreatic β cell death plays a key role in the occurrence and development of diabetes. Proinflammatory cytokines activate the apoptotic program of pancreatic β cells. Therefore, inhibiting inflammatory cytokine-induced apoptosis can protect pancreatic β cells. Lycium barbarum fruit is a widely used antioxidant food, and its pharmacological effects are partly mediated by LPB. However, whether LPB can inhibit inflammatory factor-induced β-cell apoptosis has not been reported. In this study, we found that Lycium barbarum polysaccharides can alleviate pancreatic β-cell apoptosis by inhibiting the interferon-γ (IFN-γ) pathway. Glucose tolerance was improved in healthy mice after administration of Lycium barbarum polysaccharides. In mice with streptozotocin-induced β-cell injury, preventive and continuous administration of LPB alleviated hyperglycemia and protected pancreatic insulin content. This study found that LPB has a new function of preventing and protecting pancreatic β-cell apoptosis, which is partially achieved by inhibiting the IFN-γ pathway.
Conclusion & Discussion
In this study, LPB was found to improve glucose content in normal adult mice. In addition, LPB was found to promote β-cell recovery from injury by inhibiting IFN-γ-mediated apoptosis. Although blood glucose levels did not fully return to normal during the progression of diabetes, preventive and continuous feeding of LBP alleviated hyperglycemia and maintained pancreatic insulin content during the recovery period of STZ-induced mice. This suggests that Lycium barbarum polysaccharides have a protective effect against STZ-induced pancreatic β-cell death in vivo.
The study found that under high glucose conditions, Lycium barbarum polysaccharide treatment did not promote β-cells to release more insulin. However, under low glucose levels, Lycium barbarum polysaccharides promoted β-cells to release less insulin. Therefore, Lycium barbarum polysaccharides can promote the functional maturation of pancreatic β-cells. Lycium barbarum polysaccharides have an inhibitory effect on IFN-γ, but not on IL-1β or TNF-α. Lycium barbarum polysaccharides can improve glucose tolerance in healthy mice, but have little effect on insulin sensitivity, fasting and random blood glucose levels. In addition, most genes involved in insulin secretion were not changed in SJ β-cells treated with LBP, indicating that the effect of LBP on β-cell function is mild under physiological conditions.
This study revealed the protective effect of LBP against IFN-γ-induced pancreatic β-cell apoptosis. This study not only provides the anti-apoptotic effect of LBP in pancreatic β-cells in diabetic mice, but also provides the preventive protective effect of LBP in promoting the recovery of pancreatic β-cell death in diabetic mice. Due to its wide safety range and biological effects, Lycium barbarum polysaccharides are a potential natural product that can prevent β-cell apoptosis in people susceptible to diabetes.
2. Ultrasound-assisted extraction of polysaccharides from Bauhinia chinensis and its antioxidant activity
Abstract
The purpose of this study was to improve the ultrasonic extraction process of polysaccharides from Bauhinia chinensis, compare the differences between boiling and ultrasonic extraction in polysaccharide content and monosaccharide compounds, and evaluate the effects of various factors on the bioactivity of polysaccharides from Bauhinia chinensis leaves. According to the single factor experiment and Box-Bohnken design (BBD), the optimal extraction conditions were: ultrasonic intensity of 180 W, extraction time of 40 min, water-to-solid ratio of 15:1 (g/g), and polysaccharide yield of (20.02±0.55) mg/g, which was higher than that of boiling extraction ((16.09±0.82) mg/g). The results of the antioxidant experiment showed that the polysaccharides extracted by ultrasound had higher scavenging ability of DPPH and hydroxyl free radicals, and the reducing ability was 1.2-1.4 mg/mL, which was better than that of the polysaccharides extracted by boiling. Further analysis showed that the total sugar and uronic acid contents of polysaccharides such as Gla, N-Glu and GluA purified by ultrasound were higher than those by boiling. This may indicate that the polysaccharides separated by ultrasound increased the antioxidant activity of polysaccharides.
Conclusion & Discussion
This study took the extraction of polysaccharides from Porphyra by ultrasound as the research object, and modeled and analyzed the monosaccharide compounds extracted from Schisandra polysaccharides by ultrasound and boiling and their antioxidant activities. According to the bdd design of RSM, the extraction time was 40 min, the water-to-material ratio was 15:1 (g/g), and the ultrasonic intensity was 180 W. Under these conditions, the yield of CCBLP prepared by ultrasound was (20.02±0.55) mg/g, which was higher than that prepared by boiling (16.09±0.82) mg/g. Interestingly, the experimental results showed that CCBLP extracted by ultrasound had higher DPPH, hydroxyl radical scavenging ability and reducing ability than CCBLP extracted by boiling. The analysis of monosaccharide compounds showed that ultrasonic CCBLP contained higher levels of uronic acids, such as Gla, N-Glu, and GluA. These findings further prove that the higher the content of polysaccharides and uronic acids produced by ultrasonic cryogenics and cavitation, the stronger their antioxidant activity, but the specific structure-activity process needs further research and exploration.
3. Semi-bionic extraction of astragalus polysaccharide and its in vivo anti-aging activity study
Abstract
Astragalus is a homologous plant with high medicinal and edible value. Therefore, the extraction method of astragalus polysaccharide has attracted the attention of many research teams, but the yield of its effective ingredients is still not high. In this study, astragalus polysaccharide was extracted by semi-bionic extraction, the extraction process was optimized, and the in vivo anti-aging activity of astragalus polysaccharide was evaluated. The results showed that the yield of astragalus polysaccharide extracted by semi-bionic extraction method was 18.23%. The results showed that astragalus polysaccharide extracted by this method can significantly reduce the content of malondialdehyde (MDA), increase the activity of superoxide dismutase (SOD), and inhibit D-galactose-induced aging. Serum metabolomics analysis showed that a total of 48 potential biomarkers showed significant differences, mainly involving 5 metabolic pathways. The changes in these metabolic pathways were mainly related to energy metabolism, amino acid metabolism and lipid metabolism. The above results show that the semi-bionic extraction method can effectively increase the yield of astragalus polysaccharides, and the extracted astragalus polysaccharides have anti-aging activity. This study provides a new and effective method for the extraction of astragalus polysaccharides, indicating that astragalus polysaccharides can be used as functional foods and natural medicines to delay aging and prevent its complications.
Conclusion & Discussion
Astragalus polysaccharides can significantly increase the SOD level of rats with lesions and significantly reduce the MDA expression of rats with lesions, indicating that astragalus polysaccharides affect the metabolism of rats with lesions and reduce oxidative damage. Through metabolomics research, the anti-aging pathway of astragalus polysaccharides is considered to be the amino acid metabolic pathway. Changes in metabolic gene expression and important amino acid levels are characteristics associated with animal aging. This study identified 2 different amino acid metabolic pathways through enrichment analysis of 5 pathways. One pathway is the metabolism of phenylalanine, tyrosine and tryptophan. Phenylalanine is an essential amino acid for the human body and needs to be obtained from food. Astragalus polysaccharides can change the content of phenylalanine in aging rats, which may be related to the anti-aging effect of astragalus polysaccharides. Another metabolic pathway is the metabolism of alanine, aspartic acid and glutamate. Alanine itself has no antioxidant effect, but it can synthesize carnosine in the body.
This study used a semi-bionic extraction method, and the results showed that this method can increase the yield of polysaccharides. In addition, anti-aging experiments showed that astragalus polysaccharides have the effects of delaying aging, scavenging free radicals, reducing oxidative stress, and improving amino acid and lipid metabolism in the body, which helps to strengthen our understanding of the bioactivity of functional foods. This study provides new insights into the interaction between functional foods and amino acid metabolism. However, the exact relationship between these potential biomarkers and signaling pathways is still limited and needs to be clearly elucidated in further studies.
4. White peony polysaccharide alleviates lipopolysaccharide-induced intestinal damage by regulating intestinal flora
Abstract
Increasing evidence shows that oxidative stress is closely related to inflammation and the progression of multiple chronic diseases, which seriously threatens the health of the host. Currently, polysaccharides from various plant sources have been shown to improve the negative effects of oxidative stress on the host, but the potential protective effects of white peony polysaccharide (RPAP) on the host have not been well characterized. Here, it was investigated whether RPAP administration at different doses could alleviate lipopolysaccharide (LPS)-induced intestinal damage and intestinal microbial dysbiosis in mice. The results showed that RPAP administration effectively alleviated LPS-induced intestinal damage in a dose-dependent manner. In addition, amplicon sequencing showed that RPAP administration reversed the significant decrease in intestinal microbial diversity caused by LPS exposure and restored the α-diversity index to normal levels. Microbial taxonomy studies also showed that LPS exposure led to significant changes in the composition of intestinal microorganisms, characterized by a decrease in the abundance of beneficial bacteria (Lactobacillus, Alternaria, Bacillus, Rikenellaceae_RC9_gut_group, etc.) and an increase in the content of pathogenic bacteria (Klebsiella, Helicobacter pylori, Enterococcus, etc.). However, RPAP administration, especially high-dose administration, can improve the composition of the intestinal microbiota by changing the abundance of certain bacteria. In conclusion, this study showed that RPAP administration can improve LPS-induced intestinal damage by regulating intestinal microbiota. At the same time, this also provides a basis for the promotion and application of RPAP and the alleviation of oxidative stress from the perspective of intestinal flora.
Conclusion & Discussion
This study observed that LPS exposure caused a significant decrease in intestinal microbial α-diversity, accompanied by intestinal damage. However, the addition of RPAP increased the intestinal microbial diversity index and was positively correlated with RPAP concentration, indicating that RPAP can restore LPS-induced intestinal microbial dysbiosis.
However, compared with the LPS group, the main components of intestinal microorganisms in the RH group were closer to those in the C group, suggesting that the intestinal microbial structure was improved. Consistent with previous studies, this study also showed that LPS exposure caused significant changes in the composition and structure of intestinal microorganisms, disrupting intestinal microbial homeostasis. The study also found that LPS exposure caused a significant increase in some pathogenic bacteria such as Klebsiella, Helicobacter pylori, and Enterococcus.
This study explored the protective effect of RPAP on intestinal health and microbiota in LPS-induced mice. The results showed that RPAP could restore LPS-induced intestinal damage and intestinal flora imbalance, and the effect was positively correlated with concentration. This study fills the gap in the effects of RPAP on intestinal health and microbial homeostasis caused by LPS, indicating that maintaining intestinal microbial balance may be one of the important ways for RPAP to exert its pharmacological effects. In addition, these findings also expand the understanding of the health benefits of RPAP and provide a theoretical basis for RPAP products to reduce oxidative stress. However, this study also has certain limitations, such as a relatively small sample size and a lack of intestinal metabolism experiments.
