Research on Extraction, Structure Characterization and Immunostimulatory Activity of Cell Wall Polysaccharides from Sparassis latifolia

Haematococcus pluvialis polysaccharides improve microbiota-driven gut epithelial and vascular barrier and prevent alcoholic steatohepatitis development

Algal polysaccharides possess many biological activities and health benefits, such as antioxidant, anti-tumor, anti-coagulant, and immunomodulatory potential. Gut microbiota has emerged as one of the major contributor in mediating the health benefits of algal polysaccharides. In this study we showed that Haematococcus pluvialis polysaccharides (HPP) decreased serum transaminase levels and hepatic triglyceride content, alleviated inflammation and oxidative stress in the liver of chronic and binge ethanol diet-fed mice. Furthermore, HPP reduced endotoxemia, improved gut microbiota dysbiosis, inhibited epithelial barrier disruption and gut vascular barrier (GVB) damage in ethanol diet-fed mice. Co-housing vehicle-fed mice with HPP-fed mice alleviated ethanol-induced liver damage and endotoxemia. Moreover, fecal microbiota transplantation from HPP-fed mice into antibiotic-induced microbiota-depleted recipients also alleviated ethanol-induced liver injury and improved gut epithelial and vascular barrier. Our study demonstrated that HPP ameliorated ethanol-induced gut epithelial and vascular barrier dysfunction through alteration of gut microbiota, therefore preventing alcoholic liver damage.

Sparassis latifolia and exercise training as complementary medicine mitigated the 5-fluorouracil potent side effects in mice with colorectal cancer: bioinformatics approaches, novel monitoring pathological metrics, screening signatures, and innovative management tactic

BACKGROUND

Prompt identification and assessment of the disease are essential for reducing the death rate associated with colorectal cancer (COL). Identifying specific causal or sensitive components, such as coding RNA (cRNA) and non-coding RNAs (ncRNAs), may greatly aid in the early detection of colorectal cancer.

METHODS

For this purpose, we gave natural chemicals obtained from Sparassis latifolia (SLPs) either alone or in conjunction with chemotherapy (5-Fluorouracil to a mouse colorectal tumor model induced by AOM-DSS. The transcription profile of non-coding RNAs (ncRNAs) and their target hub genes was evaluated using qPCR Real-Time, and ELISA techniques.

RESULTS

MSX2, MMP7, ITIH4, and COL1A2 were identified as factors in inflammation and oxidative stress, leading to the development of COL. The hub genes listed, upstream regulatory factors such as lncRNA PVT1, NEAT1, KCNQ1OT1, SNHG16, and miR-132-3p have been discovered as biomarkers for prognosis and diagnosis of COL. The SLPs and exercise, effectively decreased the size and quantity of tumors.

CONCLUSIONS

This effect may be attributed to the modulation of gene expression levels, including MSX2, MMP7, ITIH4, COL1A2, PVT1, NEAT1, KCNQ1OT1, SNHG16, and miR-132-3p. Ultimately, SLPs and exercise have the capacity to be regarded as complementing and enhancing chemotherapy treatments, owing to their efficacious components.

Covalent connectivity of glycogen in brewer's spent yeast cell walls revealed by enzymatic approaches and dynamic nuclear polarization NMR

Yeast cell walls undergo modifications during the brewing process, leading to a remodelling of their architecture. One significant change is the increased insolubility of the cell wall glycogen pool, likely due to the formation of covalent bonds between glycogen and cell wall polysaccharides. To verify this hypothesis, we extracted the brewer's spent yeast with 4 M KOH, obtaining an insoluble glucan fraction (AE.4 M) primarily composed of (α1 → 4)- and (1 → 3)-linked Glc residues. Dynamic nuclear polarization solid-state NMR of AE.4 M revealed distinct glucan resonances that helped to differentiate between α- and β glucosyl (1 → 4)-linked residues, and confirm covalent linkages between (β1 → 3)-glucans and glycogen through a (β1 → 4)-linkage. The hydrolysis with different endo-glucanases (zymolyase, cellulase, and lichenase) was used to obtain solubilized high molecular weight glycogen fractions. NMR analysis showed that covalent links between glycogen and (β1 → 6)-glucans through (α1 → 6) glycosidic linkage, with branching at the C6 position involving (β1 → 3), and (β1 → 6)-glucans. HPAEC-PAD analysis of the enzymatically released oligosaccharides confirmed covalent linkages of (β1 → 3), (β1 → 6)-, and (β1 → 4)-glucan motifs with (α1 → 4)-glucans. This combination of multiple enzymatic approaches and NMR methods shed light into the role of yeast cell wall glycogen as a structural core covalently linked to other cell wall components during the brewing process.

Fingerprinting Evaluation and Gut Microbiota Regulation of Polysaccharides from Jujube (Ziziphus jujuba Mill.) Fruit

Jujube fruit was well-loved and praised by the broad masses due to its delicious taste, abundant nutritional value, and medicinal properties. Few studies reported the quality evaluation and gut microbiota regulation effect of polysaccharides of jujube fruits from different producing areas. In the present study, multi-level fingerprint profiling, including polysaccharides, oligosaccharides, and monosaccharides, was established for the quality evaluation of polysaccharides from jujube fruits. For polysaccharides, the total content in jujube fruits ranged from 1.31% to 2.22%, and the molecular weight distribution (MWD) ranged from 1.14 × 10⁵ to 1.73 × 10⁶ Da. The MWD fingerprint profiling of polysaccharides from eight producing areas was similar, but the profile of infrared spectroscopy (IR) showed differentiation. The characteristic signals were screened and used to establish a discrimination model for the identification of jujube fruits from different areas, and the accuracy of identification reached 100.00%. For oligosaccharides, the main components were galacturonic acid polymers (DP, 2-4), and the profile of oligosaccharides exhibited high similarity. The monosaccharides, GalA, Glc, and Ara, were the primary monosaccharides. Although the fingerprint of monosaccharides was semblable, the composing proportion of monosaccharides revealed significant differences. In addition, the polysaccharides of jujube fruits could regulate the gut microbiota composition and possess potential therapeutic effects on dysentery and nervous system diseases.

Fingerprint profiling and gut microbiota regulation of polysaccharides from Fritillaria species

Few studies reported the quality evaluation and gut microbiota regulation effect of polysaccharides from Fritillaria species. In this study, polysaccharides extracted from ten Fritillaria species were compared and distinguished through multi-levels evaluation strategy and data fusion. Furthermore, the gut microbiota regulation effect of polysaccharides among different species was analyzed and evaluated. The fingerprint profiling of IR, molecular weight distribution of polysaccharides, chromatogram of partially hydrolyzed polysaccharides (oligosaccharides) and completely hydrolyzed polysaccharides (monosaccharides) were similar, and no exclusive signals were observed. However, the signal strength of functional group, oligosaccharides abundance and monosaccharides proportion showed obvious differences in inter- and intra-species. Glucan may be the main component of polysaccharides in Fritillaria species, CIRR derived from CIR, PRZ, DEL, TAI, UNI possessed higher total polysaccharides content, polymerization degree, oligosaccharides abundance (DP 2-4), and glucose content than the others. Meanwhile, data fusion model was established for identification of affinis and multi-original species, the accuracy of which proved to be 100 %. In addition, Fritillaria polysaccharides could increase the bacterial community richness and diversity, regulate the gut microbiota composition and possessed potential therapeutic effects on gastrointestinal diseases and nervous system diseases.

Transcriptome Analysis Revealed the Mechanism of Inhibition of Saprophytic Growth of Sparassis latifolia by Excessive Oxalic Acid

Sparassis latifolia, a highly valued edible fungus, is a crucial medicinal and food resource owing to its rich active ingredients and pharmacological effects. Excessive oxalic acid secreted on a pine-sawdust-dominated substrate inhibits its mycelial growth, and severely restricts the wider development of its cultivation. However, the mechanism underlying the relationship between oxalic acid and slow mycelial growth remains unclear. The present study reported the transcriptome-based response of S. latifolia induced by different oxalic acid concentrations. In total, 9206 differentially expressed genes were identified through comparisons of three groups; 4587 genes were down-regulated and 5109 were up-regulated. Transcriptome analysis revealed that excessive oxalic acid mainly down-regulates the expression of genes related to carbohydrate utilization pathways, energy metabolism, amino acid metabolism, protein synthesis metabolism, glycan biosynthesis, and signal transduction pathways. Moreover, genes encoding for wood-degrading enzymes were predominantly down-regulated in the mycelia treated with excessive oxalic acid. Taken together, the study results provide a speculative mechanism underlying the inhibition of saprophytic growth by excessive oxalic acid and a foundation for further research on the growth of S. latifolia mycelia.

FT-IR Method Limitations for β-Glucan Analysis

β-glucans are known as biological response modifiers. However, different sources can result in structural differences and as a result differences in their biological activity. The hot water extraction method allows to obtain, high molecular weight β-glucans without altering their structure by using strong chemicals, such as alkalis or acids. Analysis of β-glucans by FT-IR and NMR spectroscopy in solid state is superior to analysis in solution as it allows researchers to study the preserved structure of the extracted polysaccharides. FT-IR spectroscopy was used in this study to make side-by-side comparison analysis of hot water extracted β-glucans from different yeast sources. NMR spectroscopy was used to confirm findings made by FT-IR spectroscopy. Extracted β-glucans exhibit characteristic structure of β-1,3/1,6-linked glucans with noticeable levels of proteins, possibly in a form of oligopeptides, chitin and other impurities. β-glucans obtained from C. guilliermondii, P. pastoris and S. pastorianus exhibited higher protein content. Differences in mannan, chitin and α-glucan content were also observed; however, the species-specific structure of obtained β-glucans could not be confirmed without additional studies. Structural analysis of high molecular weight β-glucans in solid state by FT-IR spectroscopy is difficult or limited due to band intensity changes and overlapping originating from different molecules.