Structural characterization of Alpiniae oxyphyllae fructus polysaccharide 2 and its activation effects on RAW264.7 macrophages

The Structural Characterization of a Polysaccharide from the Dried Root of Salvia miltiorrhiza and Its Use as a Vaccine Adjuvant to Induce Humoral and Cellular Immune Responses

In order to supplement the research gap concerning Salvia miltiorrhiza polysaccharide extracted from Danshen in NMR analysis, and to clarify its immune enhancement effect as an adjuvant, we isolated and purified SMPD-2, which is composed of nine monosaccharides such as Ara, Gal, and Glc from Danshen. Its weight average molecular weight was 37.30 ± 0.096 KDa. The main chain was mainly composed of →4)-α-D-Galp-(1→, →3,6)-β-D-Glcp-(1→ and a small amount of α-L-Araf-(1→. After the subcutaneous injection of SMPD-2 as an adjuvant to OVA in mice, we found that it enhanced the immune response by activating DCs from lymph nodes, increasing OVA-specific antibody secretion, stimulating spleen lymphocyte activation, and showing good biosafety. In conclusion, SMPD-2 could be a promising candidate for an adjuvant.

Physicochemical Characterization and Biological Properties of Polysaccharides from Alpiniae oxyphyllae Fructus

Polysaccharides (AOPs) were extracted from Alpiniae oxyphyllae fructus using three distinct methods: hot water (AOP-HW), hydrochloric acid (AOP-AC), and NaOH/NaBH4 (AOP-AL). This study systematically investigated and compared the physicochemical properties, structural characteristics, antioxidant activities, and α-amylase inhibitory activities of the extracted polysaccharides. Among the three AOPs, AOP-AC exhibited the highest yield (13.76%) and neutral sugar content (80.57%), but had the lowest molecular weight (121.28 kDa). Conversely, AOP-HW had the lowest yield (4.54%) but the highest molecular weight (385.42 kDa). AOP-AL was predominantly composed of arabinose (28.42 mol%), galacturonic acid (17.61 mol%), and galactose (17.09 mol%), while glucose was the major sugar in both AOP-HW (52.31 mol%) and AOP-AC (94.77 mol%). Functionally, AOP-AL demonstrated superior scavenging activities against DPPH, hydroxyl, and ABTS radicals, whereas AOP-AC exhibited the strongest inhibitory effect on α-amylase. These findings indicate that the extraction solvent significantly influences the physicochemical and biological properties of AOPs, thus guiding the selection of appropriate extraction methods for specific applications. The results of this study have broad implications for industries seeking natural polysaccharides with antioxidant and enzymatic inhibitory properties.

Characterization of the exopolysaccharide produced by Pediococcus acidilactici S1 and its effect on the gel properties of fat substitute meat mince

Exopolysaccharide produced by lactic acid bacteria has various functions. In the present study, one anti-oxidant polysaccharide fraction, namely S1-EPS, was extracted and purified from Pediococcus acidilactici S1, and its structure and its potential effect on the gel properties of fat substitute meat mince were investigated. The results showed that S1-EPS, one of homogeneous polysaccharides, was mainly composed of Gal, Glc, and Man in molar ratio of 7.61: 15.25: 77.13 and molecular weight of 46.975 kDa. The backbone of EPS-S1 contained →2,6)-α-D-Manp-(1→，→2)-α-D-Manp-(1→,→3)-α-D-Glcp-(1 → and a small amount of→6)-β-D-Manp-(1→. The linkages of branches in EPS-S1 were mainly composed of α-D-Manp-(1→ attached to a sugar residue →2,6)-α-D-Manp-(1→O-2 or β-D-Galp-(1→ attached to a sugar residue →2,6)-α-D-Manp-(1→O-6. Furthermore, as S1-EPS increased, the meat minced gel pores decreased, and the surface became smooth. A remarkable inhibitory effect on the lipid oxidation of meat minced gel was found as S1-EPS concentration increased. Overall, S1-EPS was found to have substantial potential in low-fat meat products by serving as a natural, anti-oxidant, and functional additive.

Alpiniae oxyphyllae fructus improves production performance and egg quality of laying breeder hens by regulating reproductive hormones, antioxidant function, immunity and intestinal health

Alpiniae oxyphylla fructus was extensively utilized both as dietary supplements and traditional herbal medicines for healthcare functions and has exhibited a positive impact on animal health. The present study aimed to investigate the effects of Alpiniae oxyphyllae fructus powder (AOP) on production performance, egg quality, egg yolk fatty acid composition, reproductive hormones, antioxidant capacity, immunity, anti-apoptosis ability, and intestinal health in hens. A total of 252 Hainan Wenchang laying hens (30-wk-old) were randomly divided into 3 groups with 6 replicates, a basic diet with 0 (CON), 1 g/kg AOP (AOP1), and 3 g/kg (AOP3) mixed AOP. The AOP supplementation was found to decrease the feed conversion ratio and embryo mortality but to increase the laying rate, average egg weight, and oviduct index linearly (p < 0.05). Furthermore, AOP treatment reduced the total saturated fatty acids and palmitic acid (C16:0) in the egg yolk while increasing eggshell strength, albumen height, and Haugh unit (p < 0.05). The serum levels of albumin and phosphorus were increased, whereas total cholesterol, triglycerides, and glucose levels decreased as a result of AOP treatment (p < 0.05). The inclusion of 3 g/kg AOP had higher 17 β-estradiol and follicle-stimulating hormone levels in serum, while it up-regulated follicle-stimulating hormone receptor and gonadotropin-releasing hormone expression in ovary (p < 0.05). Dietary AOP strengthened the expression of nuclear factor erythroid2-related factor 2 in ovary and increased the activity of superoxide dismutase and total antioxidant capacity, but had a lower malondialdehyde content in serum (p < 0.05). AOP at 3 g/kg up-regulated superoxide dismutase 1 and heme oxygenase 1 expression in jejunum and ovary (p < 0.05). Meanwhile, AOP supplementation down-regulated p53 expression in ovary and bcl-2-associated x expression in liver and jejunum, especially 3 g/kg of AOP had lower caspase-8 concentrations and down-regulated bcl-2-associated x and caspase-3 expression in ovary (p < 0.05). AOP treatment increased serum levels of immunoglobulin A and immunoglobulin M and upregulated interleukin-4 expression in the liver, while decreasing interleukin-1β expression in liver and ovary and nod-like receptor protein 3 expression in jejunum (p < 0.05). Dietary AOP increased the ratio of villus height to crypt depth but decreased crypt depth in jejunum, especially when 1 g/kg AOP increased expression levels of occludin, mucin-2, peptide-transporter 1, and sodium glucose cotransporter 1 in jejunum (p < 0.05). AOP treatment altered the composition of the cecal microbial community, as evidenced by increased abundance of Oscillospira and Phascolarctobacterium and reduced richness of Clostridiaceae_Clostridium. Dietary AOP supplementation enriched lipid, amino acid, and propanoate metabolism. Spearman's correlation analysis revealed that the genera Oscillospira, Blautia, and Megasphaera were related to laying performance and intestinal integrity. In brief, supplementation of AOP, especially at 3 g/kg, could improve production performance and egg quality of hens via modulating reproductive hormones, antioxidant capacity, immunity, intestinal barrier, and cecal microbiota. Overall, the present work recommends the dietary inclusion of AOP as a beneficial additive for improving the performance of hens.

Biological Characteristics, Domesticated Cultivation Protocol, Antioxidant Activity, and Protective Effects against Cellular Oxidative Stress of an Underutilized Medicinal Mushroom: Fomitopsis palustris

Brown-rot fungus is one of the important medicinal mushrooms, which include some species within the genus Fomitopsis. This study identified wild macrofungi collected from a broad-leaved tree in Liaoning Province as Fomitopsis palustris using both morphological and molecular methods. To elucidate the potential medicinal and economic value of F. palustris, we conducted single-factor and orthogonal tests to optimize its mycelium culture conditions. Subsequently, we completed liquid culture and domestic cultivation based on these findings. Furthermore, crude polysaccharides were extracted from the cultivated fruiting bodies of F. palustris and their antioxidant activity was evaluated using chemical methods and cell-based models. The results showed that the optimal culture conditions for F. palustris mycelium were glucose as the carbon source, yeast extract powder as the nitrogen source, pH 6.0, and a temperature of 35 °C. Moreover, temperature was found to have the most significant impact on mycelial growth. The liquid strains were fermented for 6 days and then inoculated into a cultivation substrate composed of broadleaf sawdust, resulting in mature fruiting bodies in approximately 60 days. The crude polysaccharides extracted from the cultivated fruiting bodies of F. palustris (FPPs) possess in vitro scavenging abilities against DPPH radicals and OH radicals, as well as a certain ferric-reducing antioxidant power. Additionally, FPPs effectively mitigated H2O2-induced oxidative stress in RAW264.7cells by enhancing the intracellular activity of antioxidant enzymes such as SOD and CAT, scavenging excess ROS, and reducing MDA levels. This study provides preliminarily evidence of the potential medicinal and economic value of F. palustris and offers initial data for the future development and utilization of this species.

Review of isolation, purification, structural characteristics and bioactivities of polysaccharides from Portulaca oleracea L

Portulaca oleracea L., also known as purslane, affiliates to the Portulacaceae family. It is an herbaceous succulent annual plant distributed worldwide. P. oleracea L. is renowned for its nutritional value and medicinal value, which has been utilized for thousands of years as Traditional Chinese Medicine (TCM). The extract derived from P. oleracea L. has shown efficacy in treating various diseases, including intestinal dysfunction and inflammation. Polysaccharides from P. oleracea L. (POP) are the primary constituents of the crude extract which have been found to have various biological activities, including antioxidant, antitumor, immune-stimulating, and intestinal protective effects. While many publications have highlighted on the structural identification and bioactivity evaluation of POP, the underlying structure-activity relationship of POP still remains unclear. In view of this, this review aims to focus on the extraction, purification, structural features and bioactivities of POP. In addition, the potential structure-activity relationship and the developmental perspective for future research of POP were also explored and discussed. The current review would provide a valuable research foundation and the up-to-date information for the future development and application of POP in the field of the functional foods and medicine.

Immunoregulatory effects of Tetrastigma hemsleyanum polysaccharide via TLR4-mediated NF-κB and MAPK signaling pathways in Raw264.7 macrophages

Polysaccharide of Tetrastigma hemsleyanum (THP) exert antioxidant, antibacterial, lipid-lowering, and anti-inflammatory properties, especially some evidences have highlighted the efficiency of it as an anti-tumor agent. However, as a biological macromolecule with bidirectional immune regulation, the immunological enhancement effects of THP on macrophages and its underlying mechanisms are still largely unknown. In the present study, THP was prepared and characterized, and then the effect of THP on Raw264.7 cell activation was investigated. Structural characteristics of THP showed that the average molecular weight was 370.26 kDa, and the main monosaccharide composition was galactose, glucuronic acid, mannose, and glucose at a ratio of 31.56: 25.15: 19.44: 12.60, with high viscosity causing by relative high uronic acid. For immunomodulatory activity investigation, THP promoted the production of NO, IL-6 and TNF-α, as well as the expression of IL-1β, MCP-1, iNOS and COX-2, which were almost completely inhibited by TLR4 antagonist. Further study showed that THP could activate NF-κB and MAPK signaling pathways, and thus enhanced the phagocytic activity of Raw264.7 macrophages. In conclusion, the present study provided evidences that THP could be served as a new immunomodulator in both functional foods and the pharmaceutical field.

Preparation, structural characterization and neuroprotective effects to against H2O2-induced oxidative damage in PC12 cells of polysaccharides from Pleurotus ostreatus

Pleurotus ostreatus is one of the most common edible and medicinal fungi in life, and its polysaccharide has been a hot research topic in recent years. In this paper, a new intracellular polysaccharide component named P. ostreatus polysaccharide (POP-W) was obtained from the mycelium of P. ostreatus, and its structure was analyzed. The results showed that its molecular weight was Mw = 3.034 × 10³ kDa, and it did not contain protein and nucleic acid. POP-W was composed of mannose, glucose, galactose and xylose in a molar ratio of 40.34:47.60:7.97:4.09. The backbone of POP-W was α-D-Glcp(1→,→3,4)-α-D-Glcp(1→, →3,4)-α-D-Manp(1→,→3)-α -D-Galp(1→, →4)-α-D-Glcp(1→, →3)-α-D-Glcp(1→, →2)-β-D-Manp(1→, →4) -β-D-Xylp(1 →. SEM and TGA analysis showed the structure of POP-W and good thermal stability. In addition, POP-W showed significant antioxidant activity in vitro. More importantly, POP-W protected PC12 cells induced by H₂O₂ by inhibiting the contents of lactate dehydrogenase (LDH) and malondialdehyde (MDA) and increasing the levels of superoxide dismutase (SOD) and reduced glutathione (GSH). Western blot detection of Caspase-3, BAX, Bcl-2, PI3K/Akt protein expression. The results showed that POP-W inhibited the expression of caspase-3 and BAX, while promoting the expression of Bcl-2. In addition, POP-W can also promote the phosphorylation of Akt. In conclusion, POP-W pretreatment can protect PC12 cells from H₂O₂-induced oxidative damage through PI3K/Akt signaling pathway and regulation of apoptosis-related pathway proteins. It provided a theoretical basis for the practical application of the polysaccharide of P. ostreatus in production.

Extraction, purification, structural characterization, and antioxidant activity of a novel polysaccharide from Lonicera japonica Thunb

A novel water-soluble polysaccharide (HEP-4) with a molecular weight of 1.98 × 10⁵Da was extracted from honeysuckle. Structural characterization was performed using high-performance liquid chromatography (HPLC), gas chromatography, Fourier transform-infrared (FT-IR) spectrum, nucleus magnetic resonance (NMR) spectra, and scanning electron microscopy. The results showed that HEP-4 is primarily composed of mannose, rhamnose, galacturonic acid, glucose, galactose, and arabinose with a mole ratio of 6.74:1.56:1.04:14.21:4.31:5.4, and the major types of the glycosidic bond types of HEP-4 were 1-α-D-Glcp, 1,4-β-D-Glcp, 1-β-D-Arap, 1,3,4-β-D-Arap, and 1,3,6-β-D-Manp. The results of bioactivity experiments revealed that HEP-4 had antioxidant in vitro. In addition, HEP-4 inhibited H₂O₂-induced oxidative damage and increased the activity of HepG2 cells by reducing MDA levels and inhibiting ROS production. Meanwhile, HEP-4 significantly enhanced the activities of GSH-Px and CAT, indicating that HEP-4 exerts a protective effect on H₂O₂-induced oxidative stress. These results indicate that HEP-4 could be a potential natural antioxidant.

Polysaccharide from Atractylodes macrocephala Koidz binding with zinc oxide nanoparticles: Characterization, immunological effect and mechanism

Atractylodes macrocephala Koidz (A. macrocephala) has been used both as a traditional medicine and functional food for hundreds of years in Asia. And it has a variety of biological activities, such as enhancing the ability of immunity and modulating effect on gastrointestinal motility. In this study, a water-soluble polysaccharide with molecular weight of 2.743 × 10³ Da was isolated from the root of A. macrocephala. Polysaccharide from A. macrocephala (AMP) consisted of arabinose, galactose, glucose, xylose, mannose, ribose, galactose uronic acid, glucose uronic acid, with a percentage ratio of 21.86, 12.28, 34.19, 0.43, 0.92, 0.85, 28.79, and 0.67%, respectively. Zinc plays an important role in immune system. Therefore, we supposed that AMP binding with zinc oxide (ZnO) nanoparticles (AMP-ZnONPs) might be an effective immunostimulator. AMP-ZnONPs was prepared by Borch reduction, and its structural features were characterized by Scanning Electron Microscope (SEM), Transmission electron microscope (TEM), TEM-energy dispersive spectroscopy mapping (TEM-EDS mapping), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectrometer (XPS), X-ray diffraction (XRD), particle size and zeta-potential distribution analysis. Then, its immunostimulatory activity and the underlying mechanism were evaluated using RAW264.7 cells. The results showed that AMP-ZnONPs remarkably promoted cell proliferation, enhanced phagocytosis, the release of nitric oxide (NO), cytokines (IL-6 and IL-1β) and the expression of co-stimulatory molecules (CD80, CD86 and MHCII). Moreover, AMP-ZnONPs could promote the expression of Toll-like receptor 4 (TLR4), Myeloid differentiation factor 88 (MyD88), TNF receptor associated factor 6 (TRAF6), phospho-IκBα (P-IκBα) and phospho-p65 (P-p65), and TLR4 inhibitor (TAK242) inhibited the expression of these proteins induced by AMP-ZnONPs. Therefore, AMP-ZnONPs activated macrophages by TLR4/MyD88/NF-κB signaling pathway, indicating that AMP-ZnONPs could act as a potential immunostimulator in medicine and functional food.

Structural Characteristics, Antioxidant, and Immunostimulatory Activities of an Acidic Polysaccharide from Raspberry Pulp

The extraction and characterization of new bioactive plant-derived polysaccharides with the potential for use as functional foods and medicine have attracted much attention. In the present study, A novel acidic polysaccharide (RPP-3a) with a weight-average molecular weight (Mw) of 88,997 Da was isolated from the raspberry pulp. RPP-3a was composed of rhamnose, arabinose, galactose, glucose, mannose, and galacturonic acid at a molar ratio of 13.1:28.6:16.8:1.4:6.2:33.9. Structural analysis suggested that the RPP-3a backbone was composed of repeating units of →4)-β-Galp-(1→3,4)-α-Rhap-(1→[4)-α-GalAp-(1→4)-α-GalAp-(1→]_n with branches at the C-4 position of rhamnose. The side chain of RPP-3a, containing two branch levels, was comprised of α-Araf-(1→, →5)-α-Araf-(1→, →3,5)-α-Araf-(1→, →3)-β-Galp-(1→, →3,6)-β-Galp-(1→, →4)-β-Glcp-(1→, and →2,6)-α-Manp-1→ residues. RPP-3a exhibited moderate reducing power and strong hydroxyl and superoxide anion radical scavenging abilities. RPP-3a significantly promoted the viability of RAW264.7 macrophages by increasing the production of nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) at both the expression and transcriptional levels. In summary, the immunostimulatory and antioxidant activities make RPP-3a a viable candidate as a health-beneficial functional dietary supplement.

Isolation, Structural Characterization and Macrophage Activation Activity of an Acidic Polysaccharide from Raspberry Pulp

The discovery of safe and effective plant polysaccharides with immunomodulatory effects has become a research hotspot. Raspberry is an essential commercial fruit and is widely distributed, cultivated, and consumed worldwide. In the present study, a homogeneous acidic polysaccharide (RPP-2a), with a weight-average molecular weight (Mw) of 55582 Da, was isolated from the pulp of raspberries through DEAE-Sepharose Fast Flow and Sephadex G-200 chromatography. RPP-2a consisted of rhamnose, arabinose, galactose, glucose, xylose, galacturonic acid and glucuronic acid, with a molar ratio of 15.4:9.6:7.6:3.2:9.1:54.3:0.8. The results of Fourier transform infrared spectroscopy (FT-IR), gas chromatography-mass spectrometer (GC-MS), 1D-, and 2D-nuclear magnetic resonance (NMR) analyses suggested that the backbone of RPP-2a was primarily composed of →2)-α-L-Rhap-(1→, →2,4)-α-L-Rhap-(1→, →4)-α-D-GalAp-(1→, and →3,4)-α-D-Glcp-(1→ sugar moieties, with side chains of α-L-Araf-(1→, α-L-Arap-(1→, and β-D-Galp-(1→3)-β-D-Galp-(1→ residues linked to the O-4 band of rhamnose and O-3 band of glucose residues. Furthermore, RPP-2a exhibited significant macrophage activation activity by increasing the production of nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β), and the expression of inducible nitric oxide synthase (iNOS) and cytokines at the transcriptional level in RAW264.7 cells. Overall, the results indicate that RPP-2a can be utilized as a potential natural immune-enhancing agent.

DNA damage and cell apoptosis induced by fungicide difenoconazole in mouse mononuclear macrophage RAW264.7

Difenoconazole (DFC) is a typical triazole fungicide. Because of its effective bactericidal activity, it has been widely used in agricultural products such as fruits and vegetables. This study revealed the cytotoxic effect of fungicide DFC on mouse monocyte macrophage RAW264.7. The results showed that the IC₅₀ value of DFC on RAW264.7 cells was 37.08 μM (24 h). DFC can significantly inhibit the viability of RAW264.7 cells, induce DNA damage and enhance apoptosis. The established cytotoxicity test showed that DFC-induced DNA double strand breaks in RAW264.7 cells. DFC-treated cells showed typical morphological changes of apoptosis, including chromatin condensation and nuclear lysis. In addition, DFC can induce the release of Cyt c, promote the collapse of mitochondrial membrane potential and increase the Bax/Bcl-2 ratio in RAW264.7 cells. Through this research, people further understand the toxicity of DFC and provide a more scientific basis for its safety application and risk management.

Inhibition of porcine epidemic diarrhea virus by Alpiniae oxyphyllae fructus polysaccharide 3

Porcine epidemic diarrhea virus (PEDV) is a deadly pathogen that still plagues suckling piglets. However, there is still no anti-PEDV drug available in clinics. To develop potential anti-PEDV drugs, the antiviral activity of Alpiniae oxyphyllae fructus polysaccharide 3 (AOFP3) against PEDV infection in IPEC-J2 cells were assessed in our present study. The structural characterization of AOFP3 was studied by using HPAEC, GC-MS, FT-IR and NMR techniques. At the same time, the anti-PEDV activity of AOFP3 was investigated by performing RT-qPCR, Western blot and immunofluorescence assays. The results showed that AOFP3 (44.4 kDa) was composed of glucose and galacturonic acid at a molar ratio of 77.54:22.46 and consisted of →4)-α-D-Glcp-(1→, →4,6)-α-D-Glcp-(1→, T-α-D-Glcp-(1→ and →4)-α-D-GalAp-(1→. AOFP3 significantly decreased PEDV titer in IPEC-J2 cells and prevented cellular damage of IPEC-J2 cells caused by PEDV infection. Furthermore, AOFP3 showed an antioxidative activity in inhibiting PEDV reproduction. Therefore, AOFP3 was expected to be a material of anti-PEDV drug.