Purification, characterization and immunomodulatory activity of polysaccharides from Leccinum crocipodium (Letellier.) Watliag

Optimization of extraction process of polysaccharide from Phylloporia fontanesiae and its simulated digestion in vitro

In this study, Phylloporia fontanesiae polysaccharide was successfully isolated through a sequential water extraction and alcohol precipitation process. Utilizing the Box-Behnken design, the extraction process was optimized based on single-factor experiments, considering variables such as the material-to-liquid ratio, extraction temperature, extraction time, and the number of extractions. The polysaccharide composition of P. fontanesiae is predominantly composed of mannose, glucuronic acid, glucose, and galactose, with a molar mass ratio of 4.31:4.10:36.83:1, along with minor amounts of aminoglucose and fucose. The polysaccharide fraction of P. fontanesiae comprises two distinct components, possessing relative molecular masses of 8.85 kDa and 134.03 kDa. Notably, the polysaccharide exhibited significant antioxidant activity. After undergoing simulated gastrointestinal digestion, no significant changes were observed in its antioxidant activity, molecular weight, or monosaccharide composition. This study not only enhanced the extraction efficiency of P. fontanesiae polysaccharide but also provided valuable insights into its composition, structure, and digestion characteristics. PRACTICAL APPLICATION: The optimum extraction process, stability, and antioxidant activity of Phylloporia fontanesiae polysaccharide during simulated digestion of gastrointestinal tract were studied. The results provide a theoretical basis for the development and application of this polysaccharide in the field of food and health products.

Optimization of Ultrasonic-Assisted Extraction, Characterization and Antioxidant and Immunoregulatory Activities of Arthrospira platensis Polysaccharides

This study aimed to enhance the ultrasonic-assisted extraction (UAE) yield of seawater Arthrospira platensis polysaccharides (APPs) and investigate its structural characteristics and bioactivities. The optimization of UAE achieved a maximum crude polysaccharides yield of 14.78%. The optimal extraction conditions were a liquid-solid ratio of 30.00 mL/g, extraction temperature of 81 °C, ultrasonic power at 92 W and extraction time at 30 min. After purification through cellulose DEAE-52 and Sephadex G-100 columns, two polysaccharide elutions (APP-1 and APP-2) were obtained. APP-2 had stronger antioxidant and immunoregulatory activities than APP-1, thus the characterization of APP-2 was conducted. APP-2 was an acidic polysaccharide consisting of rhamnose, glucose, mannose and glucuronic acid at a ratio of 1.00:24.21:7.63:1.53. It possessed a molecular weight of 72.48 kDa. Additionally, APP-2 had linear and irregular spherical particles and amorphous structures, which contained pyranoid polysaccharides with alpha/beta glycosidic bonds. These findings offered the foundation for APP-2 as an antioxidant and immunomodulator applied in the food, pharmaceutical and cosmetic industries.

Purification, structural characterization, and immunomodulatory activity of two polysaccharides from Portulaca oleracea L

In present study, two water-soluble polysaccharides designated as POL-1 and POL-2 were purified from purslane and their structural characteristics as well as immunomodulatory activity were investigated. The weight-average molecular weight (Mw) of POL-1 and POL-2 were determined to be 64,100 Da and 21,000 Da, respectively. Comprehensive techniques including UV, IR, GC-MS, and NMR were applied to deduced that POL-1 was a pectin polysaccharide homogalacturonan (HG) consisting of →4)-α-GalpA-(1→ with methyl ester degree of 9.71 % and acetylation degree of 0.34 %, while POL-2 was composed of a 1, 4-linked β-Galp backbone substituted by short side chain →4)-α-Glcp-(1→ and →6)-α-Glcp-(1→. The →4)-α-Glcp-(1→ was attached at the O-6 position of →4)-β-Galp-(1→. TEM further revealed that POL-1 was non-branched single chains, while POL-2 was entangled microstructure with side chains. Moreover, POL-2 significantly promoted macrophage phagocytosis as well as the secretion of NO and cytokines (TNF-α, IL-6) through activating NF-κB signaling pathway, thus demonstrating potential immunomodulatory activity. These findings suggested that purslane may be exploited as a potential adjuvant and dietary supplement with immunostimulatory purpose.

Effect of Lactiplantibacillus plantarum fermentation on the physicochemical, antioxidant activity and immunomodulatory ability of polysaccharides from Lvjian okra

Okra polysaccharides exhibits a range of biological activities. To date, its processing using microbial fermentation has not been explored. This study investigated the fermentation of okra juice with various lactic acid bacteria, followed by the extraction and characterization of crude polysaccharides (termed OPS-F), in contrast to their non-fermented counterpart (OPS). Changes in physicochemical properties, antioxidant activity and immunomodulatory ability were noted. The results demonstrated that OPS-F had a 7.42-12.53 % increase in total polysaccharides content compared to OPS. However, high-performance size-exclusion chromatography indicated a reduction in the molecular weight of OPS-F (7.9-9.5 × 105 Da) relative to OPS (1.66 × 106 Da). Compared to OPS, OPS-F had reduced levels of mannose, glucose, glucuronic acid and arabinose, but increased rhamnose, galacturonic acid and galactose, exhibiting enhanced solubility and lower apparent viscosity. Fourier transform infrared spectroscopy and nuclear magnetic resonance analysis showed minimal changes in polysaccharide structure post-fermentation. Moreover, despite a decrease in antioxidant activity post-fermentation, OPS-F exhibited superior immunomodulatory potential. In conclusion, fermenting okra juice with lactic acid bacteria alters the physicochemical properties of crude polysaccharides and enhances their immunomodulatory activity, offering a promising approach for developing new functional food resources.

Effects of extraction methods on the structure and functional properties of soluble dietary fiber from blue honeysuckle (Lonicera caerulea L.) berry

The work within this study aimed to investigate and compare the effects of compound enzyme extraction (CE), ultrasonic chemical extraction (UC) and combined fermentation extraction (CF) on the physicochemical properties, microstructure, and functional properties of soluble dietary fiber (SDF) extracted from blue honeysuckle berries. The results showed that CE-SDF had higher crystallinity (32.41%). UC-SDF had the highest yield (13.32 ± 0.80 g/100 g). CF-SDF had the maximum inhibition of α-amylase (50.82 ± 0.76%) and α-glucosidase (54.87 ± 1.25%). The in vitro hypoglycemic activity of the three SDFs was observed in the order of CF > CE > UC. Meanwhile, the purity of SDF had a strong positive correlation with its antioxidant and in vitro hypoglycemic capacities. The crystallinity of SDF was found to be positively correlated with its molecular weight and thermal properties. Additionally, the sugar composition of SDF was found to be an important factor affecting its biological activity.

In vitro immunomodulatory activity study of Garcinia cowa Roxb. fraction

OBJECTIVES

The objective of this study is to determine the activity of Garcinia cowa Roxb. n-hexane, ethyl acetate, and butanol fractions as an immunomodulator in vitro and obtain the fraction that has the potential as an immunomodulator.

METHODS

Raw 264.7 macrophages were used to asses G. cowa Roxb. immunomodulatory activity. The MTT assay was chosen to measure cell viability to evaluate the cytotoxic effect on cells. ELISA method was used to measure the concentration of Interleukin-6 (IL-6) and Tumor Necrosis Factor Alpha (TNF-α) secreted by cells after being treated with G. cowa Roxb. fraction. The neutral red uptake assay determined the effect of Garcinia cowa Roxb. on the phagocytic activity.

RESULTS

After Raw 264.7 macrophages were given the Hexan fraction (Hex) at concentrations of 12.5 and 25 μg/mL, there was a decrease in the concentration of IL-6, TNF-α, and the phagocytosis index of cells. Administration of the Ethyl Acetate fraction (EtOAc) at concentrations of 12.5 and 25 μg/mL on cells caused a decrease in IL-6 and TNF-α levels but did not affect the phagocytosis index. There was an increase in the level of TNF-α and the phagocytosis index after being given the Butanol fraction (BuOH) with concentrations of 12.5 and 25 μg/mL but there was a slight decrease in the level of IL-6.

CONCLUSIONS

Both Hex and EtOAc fractions could suppress immune responses through decreasing IL-6, TNF-α, and slightly decreased phagocytic activity. BuOH fraction could stimulate immunomodulatory activities through enhanced TNF-α levels and phagocytic index, but less potent in enhancing IL-6 production. The BuOH fraction could be developed as an immunostimulant.

Structural Characteristics, Rheological Properties, and Antioxidant and Anti-Glycosylation Activities of Pectin Polysaccharides from Arabica Coffee Husks

As primary coffee by-products, Arabica coffee husks are largely discarded during coffee-drying, posing a serious environmental threat. However, coffee husks could be used as potential material for extracting pectin polysaccharides, with high bioactivities and excellent processing properties. Thus, the present study aimed to extract the pectin polysaccharide from Arabica coffee husk(s) (CHP). The CHP yield was calculated after vacuum freeze-drying, and its average molecular weight (Mw) was detected by gel permeation chromatography (GPC). The structural characteristics of CHP were determined by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), proton nuclear magnetic resonance (¹H NMR), and scanning electron microscopy (SEM). Additionally, the rheological and antioxidant properties of CHP and the inhibition capacities of advanced glycation end products (AGEs) with different concentrations were evaluated. The interaction mechanisms between galacturonic acid (GalA) and the AGE receptor were analyzed using molecular docking. The results demonstrated that the CHP yield was 19.13 ± 0.85%, and its Mw was 1.04 × 10⁶ Da. The results of the structural characteristics results revealed that CHP was an amorphous and low-methoxyl pectic polysaccharide linked with an α-(1→6) glycosidic bond, and mainly composed of rhamnose (Rha, 2.55%), galacturonic acid (GalA, 45.01%), β-N-acetyl glucosamine (GlcNAc, 5.17%), glucose (Glc, 32.29%), galactose (Gal, 6.80%), xylose (Xyl, 0.76%), and arabinose (Ara, 7.42%). The surface microstructure of CHP was rough with cracks, and its aqueous belonged to non-Newtonian fluid with a higher elastic modulus (G'). Furthermore, the results of the antioxidant properties indicated that CHP possessed vigorous antioxidant activities in a dose manner, and the inhibition capacities of AGEs reached their highest of 66.0 ± 0.35% at 1.5 mg/mL of CHP. The molecular docking prediction demonstrated that GalA had a good affinity toward AGE receptors by -6.20 kcal/mol of binding energy. Overall, the study results provide a theoretical basis for broadening the application of CHP in the food industry.

Macrophages-Related Genes Biomarkers in the Deterioration of Atherosclerosis

Background

The macrophages are involved in all stages of cardiovascular diseases, demonstrating the correlation between inflammation, atherosclerosis, and myocardial infarction (MI). Here, we aim to investigate macrophages-related genes in the deterioration of atherosclerosis.

Methods

GSE41571 was downloaded and the abundance of immune cells was estimated by utilizing the xCell. By utilizing the limma test and correlation analysis, differentially expressed macrophages-related genes (DEMRGs) were documented. The functional pathways and the protein–protein interaction (PPI) network were analyzed and the hub DEMRGs were obtained. The hub DEMRGs and their interactions were analyzed using NetworkAnalyst 3.0 and for validation, the expressions of hub DEMRGs were analyzed using the GSE135055 and GSE116250 datasets as well as atherosclerosis and MI mice model.

Results

A total of 509 differentially expressed genes (DEGs) were correlated with the abundance of macrophages and were identified as DEMRGs (Pearson correlation coefficients (PCC) > 0.6), which were mainly enriched in extracellular structure organization, lysosomal membrane, MHC protein complex binding, and so on. After screening out, 28 hub DEMRGs were obtained with degrees ≥20, including GNAI1 (degree = 113), MRPS2 (degree = 56), HCK (degree = 45), SOCS3 (degree = 40), NET1 (degree = 28), and so on. After validating using Gene Expression Omnibus (GEO) datasets and the atherosclerosis and MI mice model, eight proteins were validated using ApoE-/- and C57 mice. The expression levels of proteins, including SYNJ2, NET1, FZD7, LCP2, HCK, GNB2, and PPP4C were positively correlated to left ventricular ejection fraction (LVEF), while that of EIF4EBP1 was negatively correlated to LVEF.

Conclusion

The screened hub DEMRGs, SYNJ2, NET1, FZD7, LCP2, HCK, GNB2, EIF4EBP1, and PPP4C, may be therapeutic targets for treatment and prediction in the patients with plaque progression and MI recurrent events. The kit of the eight hub DEMRGs may test plaque progression and MI recurrent events and help in the diagnosis and treatment of MI-induced heart failure (HF), thus decreasing mortality and morbidity.

Structural characterization and immunoregulatory activity of a novel acidic polysaccharide from Scapharca subcrenata

A novel acidic polysaccharide named SSPA50-1 was isolated from Scapharca subcrenata using a simulated gastric fluid extraction method. SSPA50-1 is a heteropolysaccharide with an average molecular weight of 44.7 kDa that is composed of galacturonic acid, glucose, galactose, mannose, ribose, rhamnose, fucose, xylose and arabinose at a molar ratio of 1.00:5.40:9.04:3.10:1.59:4.01:2.10:2.21:2.28. The structural characterization based on the methylation and 1D/2D NMR analyses indicated that SSPA50-1 is composed of →3)-β-L-Rhap-(1→, →3)-β-L-2-O-Me-Fucp-(1→, →2)-α-D-Xylp-(1→, →5)-α-L-Araf-(1→, →3)-β-D-Galp-(1→, →6)-α-D-Glcp-(1→, →3,4)-β-D-Manp-(1→, →3,4)-β-D-Galp-(1→, β-D-Ribf-(1→, α-D-Glcp-(1→, and α-D-GalAp6Me-(1→. Furthermore, SSPA50-1 possessed potent immunoregulatory activity by enhancing the phagocytosis and NO, iNOS, TNF-α and IL-6 secretion capacity of RAW264.7 cells. Otherwise, SSPA50-1 significantly promoted the proliferation of splenic lymphocytes and RAW264.7 macrophages. These results indicated that SSPA50-1 could be developed as a potential ingredient for immunostimulatory agents.

Supramolecular structure features and immunomodulatory effects of exopolysaccharide from Paecilomyces cicadae TJJ1213 in RAW264.7 cells through NF-κB/MAPK signaling pathways

This study investigated the supramolecular structure features and immunomodulatory effects of two exopolysaccharide fractions (EPS1 and EPS2) from Paecilomyces cicada TJJ1213 in vitro. AFM images revealed that EPS1 and EPS2 displayed different morphological features at different concentrations. Congo red and XRD assay further proved that EPS1 and EPS2 mainly exhibited amorphous structure with random coil conformation in solution. Furthermore, the immunomodulatory effect of EPSs was investigated on RAW264.7 cells. Results showed that EPS1 and EPS2 could enhance the phagocytic activity and induce the NO production and could also significantly up-regulate the mRNA expression of iNOS, TNF-α, IL-6, IL-1β, IFN-γ and IL-4. Western blot assay analysis demonstrated that EPSs increased protein expression of TLR4 and the nuclear translocation of NF-κB p50/p65. Additionally, the phosphorylation levels of MAPKs proteins (p38, ERK and JNK) were also remarkably increased. Thus, EPSs could active TLR4-NF-κB/MAPKs signaling pathways to exert the immunomodulatory effect on macrophages.

Structural characterization of a polysaccharide from Trametes sanguinea Lloyd with immune-enhancing activity via activation of TLR4

A bioactive polysaccharide (TS2-2A) with a molecular weight of 15 kDa was isolated from Trametes sanguinea Lloyd, a medicinal food homologous fungus, by water extraction-alcohol precipitation and chromatographic separation. NMR analysis of polysaccharide and MS/MS analysis of its oligosaccharide indicated that TS2-2A featured a novel straight chain with a backbone of 1,3-α-d-glucopyranose and 1,4-β-d-glucopyranose at a molar ratio of 1:4. Moreover, TS2-2A, recognized by Toll-like receptor 4 (TLR4), stimulated RAW 264.7 macrophages to release related cytokines and contributed to immune-enhancing effects. Briefly, with remarkable immune-enhancing activity and noncytotoxicity, TS2-2A was proposed to be a potential immune enhancer for supplementing drugs or functional foods.

Assessment of the Resource Potential of Baltic Sea Macroalgae

The excess biomass of drifting algae and their casting to the Baltic Sea coast imposes a significant environmental burden. The analysis of beach-cast algae showed that the dominant species are macroalgae Ulva sp., Furcellaria lumbricalis, Cladophora sp., and Polysiphonia fucoides. The biomass of Furcellaria and Polysiphonia algae, containing 25.6% and 19.98% sugars, respectively, has the greatest resource potential in terms of obtaining carbohydrates. Fucose, glucose, and galactose were found to be the most common carbohydrates. The lipid content did not exceed 4.3% (2.3–4.3%), while the fatty acid composition was represented by saturated fatty acids (palmitic, stearic, methyloleic, behenic, etc.). The highest content of crude protein was found in samples of macroalgae of the genus Polysiphonia and amounted to 28.2%. A study of the elemental composition of drifting algae revealed that they have a high carbon content (31.3–37.5%) and a low hydrogen (4.96–5.82%), and sulfur (1.75–3.00%) content. Red algal biomass has the most resource potential in terms of biofuel generation, as it has a high number of lipids and proteins that can produce melanoidins during hydrothermal liquefaction, enhancing the fuel yield. The study noted the feasibility of using the biomass of the studied algae taxa to produce polysaccharides and biofuels. The analyses of antioxidant properties, fat content, and fat composition do not provide convincing evidence of the viability of using the aforementioned macroalgae for their production.

Bioactive Carbohydrate Polymers-Between Myth and Reality

Polysaccharides are complex macromolecules long regarded as energetic storage resources or as components of plant and fungal cell walls. They have also been described as plant mucilages or microbial exopolysaccharides. The development of glycosciences has led to a partial and difficult deciphering of their other biological functions in living organisms. The objectives of glycobiochemistry and glycobiology are currently to correlate some structural features of polysaccharides with some biological responses in the producing organisms or in another one. In this context, the literature focusing on bioactive polysaccharides has increased exponentially during the last two decades, being sometimes very optimistic for some new applications of bioactive polysaccharides, notably in the medical field. Therefore, this review aims to examine bioactive polysaccharide, taking a critical look of the different biological activities reported by authors and the reality of the market. It focuses also on the chemical, biochemical, enzymatic, and physical modifications of these biopolymers to optimize their potential as bioactive agents.

Valorization of Polysaccharides Obtained from Dark Tea: Preparation, Physicochemical, Antioxidant, and Hypoglycemic Properties

The structure and hypoglycemic activity of tea polysaccharides has been extensively studied, while there are few reports on the characterization and hypoglycemic activity of dark tea polysaccharides. The crude dark tea polysaccharide (CDTPS) was optimally extracted from Fuzhuan dark tea. Six polysaccharide fractions (namely DTPS-1, DTPS-2, DTPS-3, DTPS-4, DTPS-5, and DTPS-6) were isolated from CDTPS, and their physicochemical, structural, and biological properties were compared and analyzed. The results revealed that the compositions, structural characteristics, and biological properties of the six DTPSs were different. Therein, DTPS-4 and DTPS-6 had looser morphology, faster solubility, and a more stable structure. Additionally, DTPS-4 had the optimum in vitro antioxidant capabilities, and DTPS-6 had the strongest in vitro hypoglycemic capabilities. In addition, a correlation analysis revealed that the molecular weight and uronic acid content were significantly related to their antioxidant and hypoglycemic activities. Our results indicated that DTPS-4 and DTPS-6 could be further developed into functional foods or additives, respectively.

Characterization of a neutral polysaccharide from pumpkin (Cucurbita moschata Duch) with potential immunomodulatory activity

A neutral polysaccharide designated as CMDP-1a (molecular mass 9.263 kDa) was isolated from Cucurbita moschata Duch through hot water extraction, ethanol precipitation, and column chromatography. On the basis of methylation, fourier-transform infrared, monosaccharide composition, and one- and two-dimensional nuclear magnetic resonance spectroscopy analyses, the structure of CMDP-1a was determined to be a backbone composed of α-1,4 linked glucopyranosyl residues with α-Glcp residue linkage at backbone C-6. Atomic force microscopy and scanning electron microscopy analyses revealed that CMDP-1a had a spherical conformation in solution. In immunostimulation assays, CMDP-1a promoted the proliferation of RAW 264.7 macrophages and significantly enhanced their pinocytic and phagocytic capacity. Furthermore, CMDP-1a induced the M1 polarization of original macrophages and the conversion of macrophages from M2 to M1, thereby modulating the balance of M1/M2 macrophages. These results indicated that CMDP-1a might be a potential immunomodulator for food purposes.

Immunomodulatory effects of four polysaccharides purified from Erythronium sibiricum bulb on macrophages

Four neutral polysaccharides (ESBP1-1, ESBP1-2, ESBP2-1 and ESBP3-1) were successfully purified from the water extracted crude polysaccharides of Erythronium sibiricum bulbs through the combination of DEAE Sepharose CL-6B and Sephadex G-100 chromatography; their average molecular weights were 1.3 × 10⁴, 1.7 × 10⁴, 9.4 × 10⁵ and 4.1 × 10⁵ Da, respectively. Monosaccharide component analysis indicated that ESBP1-1 and ESBP1-2 were mainly composed of glucose (Glc). ESBP2-1 was composed of Glc, galactose (Gal) and arabinose, with a molar ratio of 24.3:1.1:1, whereas ESBP3-1 comprised Glc and Gal at a molar ratio of 14.8:1. In-vitro study showed that all of the four polysaccharides were able to considerably promote the proliferation and neutral red phagocytosis of RAW 264.7 macrophage cell. They could also stimulate the production of the cell lines' secretory molecules [nitric oxide, tumour necrosis factor-α (TNF-α) and interleukin-1β (IL-1β)] in a dose-dependent manner. However, ESBP1-2 was not included in IL-1β. Overall, these results suggested that polysaccharides from E. sibiricum bulbs can be developed as immunomodulatory ingredients for complementary medicines or functional foods. However, further animal or clinical studies are required.

An untold story of a novel mushroom from tribal cuisine: an ethno-medicinal, taxonomic and pharmacological approach

India showcases an array of fascinating and rare mushrooms that grow exclusively in the wilderness of West Bengal. Thus, the state has always been our prime choice to document myco-diversity and associated indigenous knowledge. Fortuitously, a recent expedition gifted us a violet-coloured Russuloid macrofungus, called "Jam Patra", that plays an integral part in the food security of local ethnic groups. However, the species has not received the much-needed attention among city dwellers and remains abandoned, motivating us to carry a thorough investigation. To our surprise, extensive analyses on morphological features and nrITS based phylogenetic estimation pointed the novelty of the taxon, as justified herein. Extending this research, a water-soluble polysaccharide-rich fraction was isolated to determine therapeutic prospects. Chemical characterization revealed that the backbone of the polymers, organized in triple-helical form, predominantly consisted of β-glucan accompanied by a lower extent of galactose, mannose and xylose. Subsequently, the effective antioxidant activity was noted in terms of radical scavenging, reducing power and chelating ability with EC₅₀ of 305-2726 μg ml^-1. Further, the macromolecules triggered murine macrophages to proliferate, phagocytose, release NO, produce intracellular ROS and change morphodynamics. A significant alleviation in the expression of TLR-2, TLR-4, NF-κB, COX-2, TNF-α, Iκ-Bα, IFN-γ, IL-10 and iNOS was also observed explaining the definite immune-stimulatory activity and supporting traditional consumption of "Jam Patra" as a health-promoting food. Altogether, the study introduces a species in the world's myco-diversity and tribal food list opening doors of various opportunities in functional food and nature-based drug development arenas, which are currently in trend.

In vitro therapeutic evaluation of nanoliposome loaded with Xyloglucans polysaccharides from Tamarindus flower extract

Nanoparticles are interesting area of research developed for several diagnostic and therapeutic applications. Tamarind flower extract is rich in Xyloglucan, a starch like polysaccharide which promotes proliferation and various application areas like drug-delivery technology. In recent years researchers are evaluating nanoliposome using in vitro and in vivo studies to discover their biomedical applications. Considering the importance and feasibility of nanoliposome, the present study is focused on synthesis of liposomes via biological method. The biological molecules of Tamarindus indica flower were used for the synthesis of nanoliposome. The synthesized Tamarindus indica flower extract lipid nanoparticles (TifeLiNPs) loaded with xyloglucans were characterized and evaluated for therapeutic applications (antibacterial, antioxidant, antidiabetic, anticancer and anti-inflammatory activities) under in vitro condition. UV-Vis spectral analysis revealed the emission of peak at 232 nm. Further, the chemical characterization using FTIR revealed the presence of components in the functional group. EDX analysis exhibited the presence of O, Na, P and Cl, while DLS confirmed bilayer formation of xyloglucan and liposomes with uniform size (70-80 nm) and spherical shape. The Physicochemical characterization of tamarind flower extract for its chemical composition revealed the presence of carbohydrates, alkaloids, terpenoids, glycosides, saponins, tannins and flavonoids in confirmatory test. Presence of carbohydrate polymers such as rhamnose, arabinose, galactose, glucose and xylose revealed using high performance anion exchange (HPAE) chromatography under basic conditions on an ion chromatographic system were measured using Pulsed Amperometric Detection (PAD). The synthesized nanoliposome evaluated against Gram negative and Gram positive bacteria showed potential antibacterial activity. TifeLiNPs demonstrated significant in vitro antioxidant potential, antidiabetic, anti-cancer and anti-inflammatory activity. Overall, the present study exhibited the potential application of TifeLiNPs for biomedical purposes.

Polysaccharides obtained from natural edible sources and their role in modulating the immune system: Biologically active potential that can be exploited against COVID-19

BACKGROUND

The global crisis caused by the outbreak of severe acute respiratory syndrome caused by the SARS-CoV-2 virus, better known as COVID-19, brought the need to improve the population's immunity. The foods rich in polysaccharides with immunomodulation properties are among the most highly rated to be used as immune response modulators. Thus, the use of polysaccharides obtained from food offers an innovative strategy to prevent serious side effects of viral infections.

SCOPE AND APPROACH

This review revisits the current studies on the pathophysiology of SARS-CoV-2, its characteristics, target cell interactions, and the possibility of using polysaccharides from functional foods as activators of the immune response. Several natural foods are explored for the possibility of being used to obtain polysaccharides with immunomodulatory potential. And finally, we address expectations for the use of polysaccharides in the development of potential therapies and vaccines.

KEY FINDINGS AND CONCLUSIONS

The negative consequences of the SARS-CoV-2 pandemic across the world are unprecedented, thousands of lives lost, increasing inequalities, and incalculable economic losses. On the other hand, great scientific advances have been made regarding the understanding of the disease and forms of treatment. Polysaccharides, due to their characteristics, have the potential to be used as potential drugs with the ability to modulate the immune response. In addition, they can be used safely, as they have no toxic effects, are biocompatible and biodegradable. Finally, these biopolymers can still be used in the development of new therapies and vaccines.

Effect of the structural characterization of the fungal polysaccharides on their immunomodulatory activity

The immunomodulatory effects of the four extracellular polysaccharides, namely WPA, WPB, AP2A, and TP1A, which were isolated from the fermented broth of Aspergillus aculeatus, A. terreus and Trichoderma sp. KK19L1, were investigated in vitro. WPA, WPB, AP2A, and TP1A were not toxic to RAW264.7 cells. These polysaccharides enhanced cell viability. WPA, WPB, AP2A, and TP1A showed increased immunomodulatory effect by strengthening the phagocytic activity and enhancing the release of NO, TNF-α and IL-6 from RAW264.7 cells. WPA, WPB, AP2A, and TP1A exhibited different immunomodulatory activity in vitro due to their different structural characterizations, and their immunoregulatory effects decreased successively in the following order: WPA, WPB, AP2A, and TP1A. The extracellular polysaccharides WPA, WPB, AP2A, and TP1A had potent immunomodulatory effects and could be used as potential immunomodulatory agents in the fields of functional food and medicine.