Structure elucidation and intestinal barrier protection of an α-D-glucan in Huangshui

Metabolic outcomes of Cordyceps fungus and Goji plant polysaccharides during in vitro human fecal fermentation

This study was to assess the digestion and colonic fermentation of two bioactive polysaccharides, EPS-LM and LBPS, and the subsequent influences on human gut microbiota through simulated gastrointestinal systems. EPS-LM, an exopolysaccharide isolated from mycelial culture of a medicinal fungus Cordyceps sinensis Cs-HK1, was characterized as a heteropolysaccharide consisting of Man(108):Gal(52.7):Glc(29.2) (molar ratio) with an average molecular weight (MW) 5.513 × 106. LBPS was isolated from a well-known medicinal plant (Lycium barbarum L.) which was also characterized as a heteropolysaccharide (1.236 × 105 MW). Both polysaccharides were highly resistant to saliva, gastric and small-intestine digestion with negligible MW reduction and release of reducing sugars but were quickly degraded to lower MW during in vitro human fecal fermentation. They were consumed as a carbon source by the gut bacteria to produce short-chain fatty acids (SCFAs). In comparison, the carbohydrate content of EPS-LM was more completely consumed than LBPS and there were also notable differences in consumption of specific monosaccharides and production of specific SCFAs, propionic and butyric acid, and relative abundance of gut bacterial populations between EPS-LM and LBPS group. The results suggest that metabolic outcomes and modulating effects of EPS-LM and LBPS on the gut microbiota are highly dependent on their molecular composition.

Structural identification, rheological properties and immunological receptor of a complex galacturonoglucan from fruits of Schisandra chinensis (Turcz.) Baill

A complex heteropolysaccharide SCP-2 named schisanan B (Mw = 1.005 × 105 g/mol) was obtained from water extracts of Schisandra chinensis fruits, and its planar structure was finally deduced as a galacturonoglucan by a combination of monosaccharide compositions, methylation analysis, partial acid hydrolysis, enzymatic hydrolysis and 1D/2D-nuclear magnetic resonance spectroscopy. The conformation of SCP-2 exhibited a globular shape with branching in ammonium formate aqueous solutions. The rheological properties of SCP-2 were investigated on concentrations, temperature, pH and salts. The in vitro immunomodulatory activity assay demonstrated that SCP-2 significantly enhanced the production of nitric oxide (NO) and stimulated the secretion of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) in macrophages. Through a combination of high-resolution live-cell imaging, surface plasmon resonance, and molecular docking techniques, SCP-2 exhibited a strong binding affinity with the Toll-like receptor 4 (TLR4). Moreover, western blot analysis revealed that SCP-2 effectively induced downstream signaling proteins associated with TLR4 activation, thereby promoting macrophage activation. The evidence strongly indicates that TLR4 functions as a membrane protein target in the activation of macrophages and immune regulation induced by SCP-2.

Glucans and applications in drug delivery

Glucan is a natural polysaccharide widely distributed in cereals and microorganisms that has various biological activities, including immunomodulatory, anti-infective, anti-inflammatory, and antitumor activities. In addition to wide applications in the broad fields of food, healthcare, and biomedicines, glucans hold promising potential as drug delivery carrier materials or ligands. Specifically, glucan microparticles or yeast cell wall particles are naturally enclosed vehicles with an interior cavity that can be exploited to carry and deliver drug payloads. The biological activities and targeting capacities of glucans depend largely on the recognition of glucan moieties by receptors such as dectin-1 and complement receptor 3, which are widely expressed on the cell membranes of mononuclear phagocytes, dendritic cells, neutrophils, and some lymphocytes. This review summarizes the chemical structures, sources, fundamental properties, extraction methods, and applications of these materials, with an emphasis on drug delivery. Glucans are utilized mainly as vaccine adjuvants, targeting ligands and as carrier materials for various drug entities. It is believed that glucans and glucan microparticles may be useful for the delivery of both small-molecule and macromolecular drugs, especially for potential treatment of immune-related diseases.

The Regulatory Effect of Huangshui Polysaccharides on Intestinal Microbiota and Metabolites during In Vitro Fermentation

Huangshui polysaccharides (HSPs) have attracted extensive attention recently for their biological activity and physicochemical property. This research investigated the extraction, structural characterization, and prebiotic activity of three different HSPs (HSP40-0, HSP60-0, and HSP80-0) in vitro to reveal the scientific support for the high-value utilization of Huangshui. HSPs were heteropolysaccharide with diverse structures and surface morphologies. Comprehensive analysis was conducted through 16S rRNA gene sequencing and metabolite profiling techniques, and results showed that HSPs had different potentials to regulate the gut microbiota due to their different structures; for instance, both HSP40-0 and HSP80-0 could notably increase the relative abundance of Bacteroidota, whereas HSP60-0 could increase the relative abundance of Phascolarctobacterium. In addition, HSPs upregulated beneficial differential metabolites, especially short-chain fatty acids (SCFAs). Fermentation products containing these metabolites exhibited anti-inflammatory effects on LPS-treated Caco-2 cells. This study will provide reference for exploring the relationship between the natural polysaccharide structure and the prebiotic activity and widen the application of Huangshui.

Current situation, trend, and prospects of research on functional components from by-products of baijiu production: A review

In the present scenario marked by energy source shortages and escalating concerns regarding carbon dioxide emissions, there is a growing emphasis on the optimal utilization of biomass resources. Baijiu, as the Chinese national spirit, boasts remarkably high sales volumes annually. However, the production of baijiu yields various by-products, including solid residues (Jiuzao), liquid wastewater (Huangshui and waste alcohol), and gaseous waste. Recent years have witnessed dedicated research aimed at exploring the composition and potential applications of these by-products, seeking sustainable development and comprehensive resource utilization. This review systematically summarizes recent research, shedding light on both the baijiu brewing process and the bioactive compounds present baijiu production by-products (BPBPs). The primary focus lies in elucidating the potential extraction methods and applications of BPBPs, offering a practical approach to comprehensive utilization of by-products in functional food, medicine, cosmetic, and packaging fields. These applications not only contribute to enhancing production efficiency and mitigating environmental pollution, but also introduce innovative concepts for the sustainable advancement of associated industries. Future research avenues may include more in-depth compositional analysis, the development of utilization technologies, and the promotion of potential industrialization.

Structural elucidation of a highly branched α-D-glucan from Huangjiu and its hepatoprotective activity via gut microbiome regulation and intestinal barrier repairment

Polysaccharides in Huangjiu, a traditional fermented food, are expected to be potentially effective ingredients in protecting against alcoholic liver disease (ALD). Elucidating their precise structural and functional characteristics is essential for in-depth understanding of structure-activity relationships of hepatoprotective polysaccharides. Herein, a major polysaccharide component HJPS1-2 was purified from Huangjiu with an average molecular weight of 3.49 kDa. Structural analyses inferred that HJPS1-2 backbone was composed of (1 → 4)-linked α-D-Glcp and a single α(1 → 6)-D-Glcp-α(1 → 6)-D-Glcp branched unit for every three α(1 → 4)-D-Glcp. An ALD mouse model was further established to clarify the underlying effect of HJPS1-2 on ALD alleviation. Biochemical detection and histopathological assessment revealed that HJPS1-2 intervention remarkably improved ethanol-induced hepatic dysfunction and steatosis. HJPS1-2 treatment ameliorated gut microbiota dysbiosis of ALD mice in a dose-dependent manner, mainly manifested as restoration of microbial diversities, community structure and bacterial interaction patterns. Compared with ethanol group, the strikingly elevated intestinal short-chain fatty acids' levels and enhanced intestinal barrier function after HJPS1-2 intake might contribute to reduced serum and liver lipopolysaccharide levels and subsequently suppressed release of hepatic inflammatory cytokines, thus mitigating ALD. Collectively, this research supports the potential of food-derived polysaccharides to hinder the early formation and progression of ALD through maintaining intestinal homeostasis.

Preparation, Structural Analysis, and Intestinal Probiotic Properties of a Novel Oligosaccharide from Enzymatic Degradation of Huangshui Polysaccharide

Huangshui polysaccharide (HSP) has attracted more and more interest due to its potential health benefits. Despite being an excellent source for the preparation of oligosaccharides, there are currently no relevant research reports on HSP. In the present study, a novel oligosaccharide (HSO) with a molecular weight of 1791 Da and a degree of polymerization of 11 was prepared through enzymatic degradation of crude HSP (cHSP). Methylation and NMR analyses revealed that the main chain of HSO was (1 → 4)-α-d-glucose with two O-6-linked branched chains. Morphological observations indicated that HSO exhibited smooth surface with lamellar and filamentary structure, and the glycan size ranged from 0.03 to 0.20 μm. Notably, HSO significantly promoted the proliferation of Bifidobacterium, Bacteroides, and Phascolarctobacterium, thereby making positive alterations in intestinal microbiota composition. Moreover, HSO markedly increased the content of short-chain fatty acids during in vitro fermentation. Metabolomics analysis illustrated the important metabolic pathways primarily involving glucose metabolism, amino acid metabolism, and fatty acid metabolism.

A portable sensor for glucose detection in Huangshui based on blossom-shaped bimetallic organic framework loaded with silver nanoparticles combined with machine learning

In this work, we propose a blossom-like Ni, Co bimetallic metal-organic framework (NiCo-MOF) synthesized hydrothermally and decorated with silver nanoparticles (AgNPs) via chemical reduction for electrochemical enzyme-free glucose sensing. The NiCo-MOF nanostructures had large specific surface area and good sensing performance. The AgNPs enhanced the electrochemical performance of the MOF, resulting in excellent electrochemical activity. The sensor exhibited sensitivities of 1191.84 and 271.19 μA mM-1 cm-2 in the linear ranges of 0.005-1.125 and 1.525-5.325 mM, respectively, with a detection limit of 2.3 μM. The sensor was successfully applied for glucose determination in Huangshui (HS) using an artificial neural network as machine learning (ML) model. The R2 value near 1, low RMSE, and high RPD values of the proposed ML model demonstrate its excellent fitting and prediction performance. This will provide a fast and portable intelligent sensing analysis technology for the detection of glucose in HS.

The Prebiotic Activity of a Novel Polysaccharide Extracted from Huangshui by Fecal Fermentation In Vitro

A novel polysaccharide, HSP80-2, with an average molecular weight of 13.8 kDa, was successfully isolated by the gradient ethanol precipitation (GEP) method from Huangshui (HS), the by-product of Chinese Baijiu. It was mainly composed of arabinose, xylose, and glucose with a molar ratio of 4.0:3.1:2.4, which was completely different from the previous reported HS polysaccharides (HSPs). Morphological observations indicated that HSP80-2 exhibited a smooth but uneven fragmented structure. Moreover, HSP80-2 exerted prebiotic activity evaluated by in vitro fermentation. Specifically, HSP80-2 was utilized by gut microbiota, and significantly regulated the composition and abundance of beneficial microbiota such as Phascolarctobacterium, Parabacteroides, and Bacteroides. Notably, KEGG pathway enrichment analysis illustrated that HSP80-2 enriched the pathways of amino sugar and nucleotide sugar metabolism (Ko00520), galactose metabolism (ko00052), and the citrate cycle (TCA cycle) (ko00020). Meanwhile, the contents of short-chain fatty acids (SCFAs) mainly including acetic acid, propionic acid, and butyric acid in the HSP80-2 group were remarkably increased, which was closely associated with the growth of Lachnoclostridium and Parabacteroides. These results showed that HSP80-2 might be used as a potential functional factor to promote human gut health, which further extended the high value utilization of HS.

Huangshui Polysaccharide Exerts Intestinal Barrier Protective Effects through the TLR4/MyD88/NF-κB and MAPK Signaling Pathways in Caco-2 Cells

Several reports have demonstrated that natural polysaccharides exert protective effects on intestinal barrier function. In our previous study, we isolated a polysaccharide named HSP-W from Huangshui (HS). In the present study, the protective role of HSP-W in LPS-induced intestinal barrier dysfunction was determined by several molecular biological techniques. The results showed that HSP-W treatment alleviated the deduced TEER and increased the permeability of intestinal epithelial cells induced by LPS through inhibiting the release of inflammatory cytokines and enhancing the expression of tight junction (TJ) proteins. The underlying molecular mechanisms were elucidated by RNA-seq technique, which indicated that the differentially expressed genes (DEGs) between the LPS-treated and LPS+HSP-W-treated groups were enriched in the "MAPK" signaling pathway. Notably, the overlapping DEGs reversed by HSP-W intervention highlighted the pathways of the "Toll-like receptor" and "NF-κB" signaling pathways. The suppression of p38 and NF-κB were mediated by the inhibition of MyD88. Furthermore, HSP-W treatment prevented the translocation of NF-κB to nucleus, thus inhibiting the release of TNF-α, IL-6, and IL-1β. Overall, HSP-W has beneficial effects on LPS-induced inflammation; it protects the intestinal barrier from injury in Caco-2 cells through inhibiting the TLR4/MyD88/NF-κB and p38 MAPK signaling pathways.