Neutral Polysaccharide from the Leaves of Pseuderanthemum carruthersii: Presence of 3-O-Methyl Galactose and Anti-Inflammatory Activity in LPS-Stimulated RAW 264.7 Cells

Production and characterization of exopolysaccharides from salinity-induced Auxenochlorella protothecoides and the analysis of anti-inflammatory activity

The set scenario of this work was to investigate the production, physicochemical characteristics, and anti-inflammatory activities of exopolysaccharides from salinity-induced Auxenochlorella protothecoides. The results demonstrated that 10 ‰ salinity manipulation endowed preferable exopolysaccharide production by A. protothecoides. Under this salinity stress, ACPEPS1A and ACPEPS2A were purified from exopolysaccharide production by anion chromatography and molecular exclusion chromatography. ACPEPS1A exhibited a molecular weight (Mw) of 132 kDa and mainly consisted of galactose. ACPEPS2A was a heteropolysaccharide with an Mw of 170 kDa and the main monosaccharides of galactose and rhamnose with separate molar percents of 42.41 % and 35.29 %, respectively. FTIR, ¹H and ¹³C NMR supported that monosaccharide components of ACPEPS1A and ACPEPS2A possessed both α- and β-configuration pyranose rings. Further evidence indicated that ACPEPS1A and ACPEPS2A could effectively inhibit the inflammatory response in lipopolysaccharide (LPS) induced RAW264.7 cells by quenching inflammatory factor levels such as ROS, iNOS, TNF-α, and IL-6. The potential anti-inflammatory possibilities were that the monosaccharides of ACPEPS1A and ACPEPS2A possessed higher affinity with receptors on the macrophage surface than LPS and hampered LPS-induced inflammation. The findings of this work would favor innovative applications of exopolysaccharides from microalgae in complementary medicines or functional foods.

A network pharmacology strategy combined with in vitro experiments to investigate the potential anti-inflammatory mechanism of Prunus cerasifera Ehrhart

This study aimed to investigate the anti-inflammatory activity of Prunus cerasifera Ehrhart (EHP). LC-MS/MS, network pharmacology, enzyme-linked immunosorbent assay (ELISA), and Western blot analysis methods were used to investigate the chemical composition and the anti-inflammatory mechanism of EHP. The LC-MS/MS results showed that flavonoids and phenolic acids were the major compounds in EHP. The network pharmacology analysis results indicated that EHP was related to TNF, inflammatory cytokine, and MAPK signaling pathway. ELISA and Western blot results showed that EHP impeded the increase in inflammatory factors, inducible nitric oxide synthase (iNOS), cyclooxygenase 2 (COX-2), nuclear transcription factors κB (p65), MAPK pathway, pyrolytic relevant proteins nod-like receptor family pyrin domain-containing 3 (NLRP3), and interleukin-1β (IL-1β) induced by lipopolysaccharide (LPS) and activated the nuclear factor erythroid 2-related factor 2 (Nrf2)/hemeoxygenase-1 (HO-1) pathway. Therefore, this research highlighted the potential application of P. cerasifera in the development of anti-inflammatory foods that prevented inflammatory diseases. PRACTICAL APPLICATIONS: In recent years, many synthetic drugs with anti-inflammatory effect have the disadvantages of high price and side effects. Thus, the development of anti-inflammatory drugs from natural resources has its application value. In this study, LPS-stimulated RAW264.7 cells were used to establish inflammatory model to verify the anti-inflammatory effect of Prunus cerasifera (EHP). The results showed that P. cerasifera possessed anti-inflammatory activity through inhibiting pro-inflammatory cytokines secretion, NF-κB, MAPK pathway, and NLRP3 inflammasome activation. Therefore, P. cerasifera has the potential to develop into functional food to prevent the progress of various inflammatory-related diseases.

Separation and Structural Characterization of a Novel Exopolysaccharide from Rhizopus nigricans

The present study aims to analyze the structural characterization and antioxidant activity of a novel exopolysaccharide from Rhizopus nigricans (EPS2-1). For this purpose, EPS2-1 was purified through DEAE-52, Sephadex G-100, and Sephadex G-75 chromatography. The structural characterization of EPS2-1 was analyzed using high-performance gel permeation chromatography (HPGPC), Fourier transform infrared spectroscopy (FT-IR), methylation analysis, nuclear magnetic resonance (NMR) spectra, transmission electron microscope (TEM), and atomic force microscope (AFM). The results revealed that EPS2-1 is composed of mannose (Man), galactose (Gal), glucose (Glc), arabinose (Ara), and Fucose (Fuc), and possesses a molecular weight of 32.803 kDa. The backbone of EPS2-1 comprised →2)-α-D-Manp-(1→ and →3)-β-D-Galp-(1→, linked with the O-6 position of (→2,6)-α-D-Manp-(1→) of the main chain is branch α-D-Manp-(1→6)-α-D-Manp-(1→, linked with the O-6 positions of (→3)-β-D-Galp-(1→) of the main chain are branches →4)-β-D-Glcp-(1→ and →3)-β-D-Galp-(1→, respectively. Finally, we demonstrated that EPS2-1 also shows free radical scavenging activity and iron ion reducing ability. At the same time, EPS2-1 could inhibit the proliferation of MFC cells and increase the cell viability of RAW264.7 cells. Our results suggested that EPS2-1 is a novel polysaccharide, and EPS2-1 has antioxidant activity. In addition, EPS2-1 may possess potential immunomodulatory and antitumor activities. This study promoted the application of EPS2-1 as the functional ingredients in the pharmaceutical and food industries.

Anti-inflammatory effect of a polysaccharide fraction from Craterellus cornucopioides in LPS-stimulated macrophages

Immunocytes-involved inflammation is considered to modulate the damage in various diseases. Oxidative stress is initiated by oxidative agents such as LPS and ROS, which are strongly involved in chronic inflammation. Our previous study found that a polysaccharide fraction from Craterellus cornucopioides (CCPP-1) showed good antioxidant activity. However, the anti-inflammatory effect of CCPP-1 was still elusive. The objective of this study was to evaluate the anti-inflammatory activity of CCPP-1 and its potential mechanism in LPS-stimulated RAW264.7 macrophages. The results showed that CCPP-1 could inhibit LPS-induced ROS and NO accumulation. Additionally, CCPP-1 could decrease pro-inflammatory cytokines production (TNF-α, IL-1β, and IL-18) and inflammatory mediator (iNOS) expression, which might be associated with its capacity to inhibit NF-κB signaling pathway and NLRP3 inflammasome activation. Therefore, this study suggested that CCPP-1 had an ameliorative effect on the inflammation response and was potential to develop into functional food for treating chronic inflammation. PRACTICAL APPLICATIONS: Craterellus cornucopioides is an edible fungus widely distributed in Southwestern China. It was reported that C. cornucopioides polysaccharide (CCPP-1), as important active ingredient, showed good antioxidant activity. However, the anti-inflammatory effect was still elusive. This study showed that CCPP-1 possessed anti-inflammatory activity. The molecular mechanism might be associated with its capacity to inhibit NF-κB signaling pathway and NLRP3 inflammasome activation. Therefore, polysaccharides from C. cornucopioides have potential to develop into functional food to combat inflammatory condition and thus indirectly halt the progression of various inflammatory response-related chronic diseases.

Combined whole cell wall analysis and streamlined in silico carbohydrate-active enzyme discovery to improve biocatalytic conversion of agricultural crop residues

The production of biofuels as an efficient source of renewable energy has received considerable attention due to increasing energy demands and regulatory incentives to reduce greenhouse gas emissions. Second-generation biofuel feedstocks, including agricultural crop residues generated on-farm during annual harvests, are abundant, inexpensive, and sustainable. Unlike first-generation feedstocks, which are enriched in easily fermentable carbohydrates, crop residue cell walls are highly resistant to saccharification, fermentation, and valorization. Crop residues contain recalcitrant polysaccharides, including cellulose, hemicelluloses, pectins, and lignin and lignin-carbohydrate complexes. In addition, their cell walls can vary in linkage structure and monosaccharide composition between plant sources. Characterization of total cell wall structure, including high-resolution analyses of saccharide composition, linkage, and complex structures using chromatography-based methods, nuclear magnetic resonance, -omics, and antibody glycome profiling, provides critical insight into the fine chemistry of feedstock cell walls. Furthermore, improving both the catalytic potential of microbial communities that populate biodigester reactors and the efficiency of pre-treatments used in bioethanol production may improve bioconversion rates and yields. Toward this end, knowledge and characterization of carbohydrate-active enzymes (CAZymes) involved in dynamic biomass deconstruction is pivotal. Here we overview the use of common "-omics"-based methods for the study of lignocellulose-metabolizing communities and microorganisms, as well as methods for annotation and discovery of CAZymes, and accurate prediction of CAZyme function. Emerging approaches for analysis of large datasets, including metagenome-assembled genomes, are also discussed. Using complementary glycomic and meta-omic methods to characterize agricultural residues and the microbial communities that digest them provides promising streams of research to maximize value and energy extraction from crop waste streams.