Structural characteristics and bioactivities of polysaccharides from blue honeysuckle after probiotic fermentation

Fermented Gracilaria lemaneiformis polysaccharides alleviate food allergy by regulating Treg cells and gut microbiota

Food allergy has a significant impact on the health and well-being of individuals, affecting both their physical and mental states. Research on natural bioactive compounds, such as polysaccharides extracted from seaweeds, holds great promise in the treatment of food allergies. In this study, fermented Gracilaria lemaneiformis polysaccharides (F-GLSP) were prepared using probiotic fermentation. Probiotic fermentation of Gracilaria lemaneiformis reduces the particle size of polysaccharides. To compare the anti-allergic activity of F-GLSP with unfermented Gracilaria lemaneiformis polysaccharides (UF-GLSP), an OVA-induced mouse food allergy model was established. F-GLSP exhibited a significant reduction in OVA-specific IgE and mMCP levels in allergic mice. Moreover, it significantly inhibited Th2 differentiation and IL-4 production and significantly promoted Treg differentiation and IL-10 production in allergic mice. In contrast, UF-GLSP only reduced OVA-specific IgE and mMCP in the serum of allergic mice. Furthermore, F-GLSP demonstrated a more pronounced regulation of intestinal flora abundance compared to UF-GLSP, significantly influencing the populations of Firmicutes, Bacteroidetes, Lactobacillus, and Clostridiales in the intestines of mice with food allergy. These findings suggest that F-GLSP may regulate food allergies in mice through multiple pathways. In summary, this study has promoted further development of functional foods with anti-allergic properties based on red algae polysaccharides.

Effects of Lactobacillus plantarum FM 17 fermentation on jackfruit polysaccharides: Physicochemical, structural, and bioactive properties

Fermentation is a novel technology for modifying polysaccharides in fruits and improving their bioactivities. In this work, we introduced Lactobacillus plantarum FM 17 to ferment jackfruit pulp and subsequently purified polysaccharides from unfermented (JP) and fermented jackfruit pulp (JP-F). Furthermore, the physicochemical, structural, and bioactive properties of JP and JP-F were investigated. Results showed fermentation dropped the glucuronic acid, molecular weight, and particle size of JP-F by 15.62 %, 23.92 %, and 39.43 %, respectively, compared with those of JP. JP-F showed higher solubility than JP but lower apparent viscosity and thermal stability. Additionally, FT-IR spectra and X-ray diffraction analysis showed that fermentation did not alter the different types of glycosidic bonds and the fundamental polysaccharide structure. Moreover, JP-F exhibited stronger DPPH and ABTS free radical scavenging properties than JP and stronger stimulation on macrophage secretion of NO and IL-6 in RAW 264.7 cells. Therefore, using L. plantarum FM 17 for fermentation can alter physical and chemical properties of jackfruit pulp polysaccharides, enhancing their bioactivities.

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.

Evaluation of antioxidation, regulation of glycolipid metabolism and potential as food additives of exopolysaccharide from Sporidiobolus pararoseus PFY-Z1

At present, there are relatively few studies on the production of exopolysaccharide (EPS) by yeasts. Therefore, exploring the properties of EPS produced by yeast can not only enrich the source of EPS, but also play an important role in its future application in the food field. The aim of this study was to explore the biological activities of EPS (named SPZ) from Sporidiobolus pararoseus PFY-Z1, as well as the dynamic changes in physical and chemical properties that occur during simulated gastrointestinal digestion, and the effects of SPZ on microbial metabolites during fecal fermentation in vitro. The results revealed that SPZ had good water solubility index, water-holding capacity, emulsifying ability, coagulated skim milk, antioxidant properties, hypoglycemic activities, and bile acid-binding abilities. Furthermore, the content of reducing sugars increased from 1.20 ± 0.03 to 3.34 ± 0.11 mg/mL after gastrointestinal digestion, and had little effect on antioxidant activities. Moreover, SPZ could promote the production of short-chain fatty acids during fermentation for 48 h, in particular, propionic acid and n-butyric acid increased to 1.89 ± 0.08 and 0.82 ± 0.04 mmol/L, respectively. Besides this, SPZ could inhibit LPS production. In general, this study can help us to better understand the potential bioactivities, and the changes in bio-activities of compounds after digestion of SPZ.

Recent advances in polysaccharide biomodification by microbial fermentation: production, properties, bioactivities, and mechanisms

Polysaccharides are natural chemical compounds that are extensively employed in the food and pharmaceutical industries. They exhibit a wide range of physical and biological properties. These properties are commonly improved by using chemical and physical methods. However, with the advancement of biotechnology and increased demand for green, clean, and safe products, polysaccharide modification via microbial fermentation has gained importance in improving their physicochemical and biological activities. The physicochemical and structural characteristics, biological activity, and modification mechanisms of microbially fermented polysaccharides were reviewed and summarized in this study. Polysaccharide modifications were categorized and discussed in terms of strains and fermentation techniques. The effects of microbial fermentation on the physicochemical characteristics of polysaccharides were highlighted. The impact of modification of polysaccharides on their antioxidant, immune, hypoglycemic, and other activities, as well as probiotic digestive enhancement, were also discussed. Finally, we investigated a potential enzyme-based process for polysaccharide modification via microbial fermentation. Modification of polysaccharides via microbial fermentation has significant value and application potential.

Purification of exopolysaccharides from Lactobacillus rhamnosus and changes in their characteristics by regulating quorum sensing genes via polyphenols

To explore the effect of Lonicera caerulea fruit polyphenols (LCP) on caries-causing bacteria, strain RYX-01 with high production of biofilm and exopolysaccharides (EPS) was isolated from the oral cavity of caries patients and was identified as Lactobacillus rhamnosus by 16S rDNA analysis and morphology. The characteristics of EPS produced by RYX-01 (EPS-CK) and those produced by adding L. caerulea fruit polyphenols (EPS-LCP) were compared to reveal whether LCP reduced the cariogenicity of RYX-01 by influencing the structure and composition of EPS. The results showed that LCP could increase the content of galactose in EPS and destroy the original aggregation state of EPS-CK but had no significant effect on the molecular weight and functional group composition of EPS (p > 0.05). At the same time, LCP could inhibit the growth of RYX-01, reduce EPS and biofilm formation and inhibit the expression of quorum sensing (QS, luxS)- and biofilm formation (wzb)-related genes. Therefore, LCP could change the surface morphology, content and composition of RYX-01 EPS and reduce the cariogenic effect of EPS and biofilm. In conclusion, LCP can be used as a potential plaque biofilm inhibitor and QS inhibitor in drugs and functional foods.

Effect of fermentation modification on the physicochemical characteristics and anti-aging related activities of Polygonatum kingianum polysaccharides

In order to fully investigate the anti-aging value of the plants polysaccharides, the fermentation method was applied to modify the Polygonatum kingianum polysaccharides (PKPS), and the ultra-filtration was used to further segment the hydrolyzed polysaccharides. It was found that the fermentation induced an increase in the in vitro anti-aging-related activities of PKPS including antioxidant, hypoglycemic and hypolipidemic activity, and cellular aging-delaying ability. In particular, the low Mw fraction PS2-4 (10-50 kDa) separated from the fermented polysaccharide exhibited superior anti-aging activity on experimental animals. PS2-4 extended the Caenorhabditis elegans lifespan by 20.70 %, with an increased effect of 10.09 % compared to the original polysaccharide; it was also more effective than the original one in improving movement ability and reducing lipofuscin accumulation of worms. This fraction was screened as the optimal anti-aging active polysaccharide. After fermentation, the main molecular weight distribution of PKPS changed from 50-650 kDa to 2-100 kDa, and the chemical composition and monosaccharide composition also changed; the initial rough and porous microtopography turned into smooth state. These alterations in physicochemical characteristics suggest that fermentation exerted an influence on the structure of PKPS, which contributed to the enhanced anti-aging activity, indicating that fermentation was promising in the structural modification of polysaccharides.

Production, characterization and antioxidant activity of exopolysaccharide from Sporidiobolus pararoseus PFY-Z1

At present, the study on exopolysaccharid is mainly focused on lactic acid bacteria, and the research on exopolysaccharide produced by yeast, especially Sporidiobolus pararoseus, is relatively few. Therefore, the aim of this study was to explore the characterization and antioxidant activities of a novel neutral exopolysaccharide SPZ, which was isolated and purified from S. pararoseus PFY-Z1. The results showed that SPZ was mainly composed of mannose, followed by glucose, with a molecular weight was 24.98 kDa, had O-glycosidic bonds, no crystalline, and no triple helix structure. Based on fourier transform-infrared, high-performance liquid chromatography and nuclear magnetic resonance analyses, SPZ was identified to be a exopolysaccharide with some side chains, presence of α-, β-pyranose ring and nine sugar residues. Furthermore, the morphology features of SPZ have performed a relatively rough and uneven surface, covered with small pores and fissures. Moreover, SPZ had higher antioxidant activities and the maximum scavenging abilities of ⋅OH, NO₂^- and reducing power were 28.05 ± 0.73%, 92.76 ± 1.86% and 0.345 ± 0.024, respectively. Hence, SPZ could be used as a potential antioxidant application in the food and pharmaceutical industries.

Structural Characteristics and the Antioxidant and Hypoglycemic Activities of a Polysaccharide from Lonicera caerulea L. Pomace

In this study, a novel polysaccharide, LPP, was obtained from Lonicera caerulea L. pomace by ultrasonic-assisted heating and was purified by Sephadex G-100. The structural characteristics of LPP showed that the molecular weight (Mw) was 8.53 × 104 Da; that it was mainly composed of galacturonic acid, followed by galactose; that it possessed the characteristic functional groups of polysaccharides; and that it had an absence of O-glycosidic bonds and crystalline and triple helix structures. Furthermore, LPP exhibited a favorable thermodynamic stability and antioxidant, hypoglycemic, and hypolipidemic activities in a dose-dependent manner in vitro, demonstrating that LPP can be used as an agent to regulate glycolipid metabolism. Additionally, the relationship between its bio-activities is discussed in this paper. The results revealed that the RP, •OH, and NO2− radicals had synergistic promoting effects, and polysaccharides with a strong antioxidant ability may have excellent hypoglycemic and hypolipidemic effects. Collectively, these results suggest that LPP has a strong bio-activity, and that Lonicera caerulea L. pomace can be used as a potential polysaccharide source.