Structure analysis and antioxidant activity of polysaccharide-iron (III) from Cordyceps militaris mycelia

Characterization of Choerospondias axillaris polysaccharide‑iron (III) complex and its effect on iron deficiency anemia mice

Iron deficiency anemia (IDA) is a prevalent nutritional deficiency problem. This study aimed to investigate the characteristics of Choerospondias axillaris polysaccharide-Fe (III) complex and its effect on IDA mice. CAP-Fe (III) complex was synthesized by co-thermal synthesis method with an iron content of 27.31 ± 0.97 %. The chelation of Fe3+ reduced the crystallinity, increased the thermal stability and changed the morphological features of CAP, which was evidenced by XRD, TG, and SEM analysis. The probable existence of the β-FeOOH structure was supported by the characteristic absorption peaks in the FT-IR, XRD, and Mössbauer spectra. The CAP-Fe (III) complex showed a therapeutic effect on IDA mice, confirmed by improved erythroid parameters, iron levels, and oxidative stress. The results of gene expression levels determined by RT-qPCR demonstrated that the CAP-Fe (III) complex could regulate iron metabolism homeostasis, alleviate liver inflammation, and enhance intestinal barrier function. Furthermore, the dysbiosis of intestinal microbiota induced by IDA was effectively restored by CAP-Fe (III) complex, through enriching beneficial bacteria (Firmicutes, Blautia, Oscillibacter, Colidextribacter) and depleting harmful bacteria (Actinobacteria, Proteobacteria, Parasutterella, Faecalibaculum, Escherichia-Shigella). These findings suggested that CAP-Fe (III) may serve as a novel iron supplement for treating IDA.

Research progress of edible mushroom polysaccharide-metal trace element complexes

Metal trace elements are crucial for human health, and the complexes of edible mushroom polysaccharides with metal trace elements are currently a research hotspot in the field of food science. This article reviews the preparation methods, structural characterization, and physiological activities of edible mushroom polysaccharide-metal trace element complexes, including iron, selenium, and zinc. Research has shown that iron complexes obtained through Co-thermal synthesis of the FeCl3 method exhibit excellent antioxidant and anti-anemia functions; selenium complexes prepared via selenium-enriched cultivation significantly enhance immunological and anti-cancer properties; zinc complexes improve lipid-lowering, liver protection, and antioxidant capabilities. However, there is an imbalance in research among different metal elements, particularly with a high density of studies on selenium complexes. These studies provide a foundation for the future development of edible mushroom polysaccharide-metal trace element complexes.

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.

A highly branched glucomannan from the fruiting body of Schizophyllum commune: Structural characteristics and antitumor properties analysis

In this study, a highly branched glucomannan (SCP-1) from Schizophyllum commune fruiting body with good solubility was isolated, and its structural characteristics and antitumor properties were analyzed. The monosaccharides of SCP-1 were fucose, glucosamine hydrochloride, galactose, glucose and mannose with a relative molar ratio of 14:6:210:593:177, and the molecular weight (Mw) of SCP-1 was 15.1 kDa. SCP-1 showed a rough and dense surface, and it was aggregated to particles in distilled water, though it might have triple-helix conformation. The main backbone chain of SCP-1 was →[3)-β-D-Glcp-(1]3→3)-β-D-Glcp-(1→2)-α-D-Manp-(1→2)-α-D-Manp-(1→3)-α-D-Glcp-(1→ and three sides chains including α-D-Glcp-(1→[6)-β-D-Glcp-(1]2→, α-D-Glcp-(1→3)-α-D-Manp-(1→ and α-D-Glcp-(1→[6)-α-D-Galp-(1]3→ were linked with 1,6-glycosidic bond, which was significantly different with the schizophyllan isolated from the mycelia of S. commune. SCP-1 could significantly inhibit the growth of A549 cells, the inhibition rate reached 41.62 % and the percentage of cells in S phase increased from 27.17 % to 56.40 % (400 μg/mL, 48 h). Moreover, SCP-1 could induce cell apoptosis and the total apoptosis rate reached 28.13 %. SCP-1 exerted apoptosis inducing effect probably by reducing the expression ratio of Bcl-2/Bax and the p-PI3K, p-Akt and p-mTOR expression level. The results showed that SCP-1 might have the potential to act as an antitumor agent for lung cancer therapy.

A mini-review of isolation, purification, structural characteristics and bioactivities of polysaccharides from Aralia elata (Miq.) Seem

In recent years, the isolation, purification, structural characterization of plant polysaccharides from natural resources have arrested widespread attention. Aralia elata (Miq.) Seem (A. elata) belongs to the Aralia genus of the Araliaceae family, which is one of the most popular edible mountain vegetables in East Asia. A. elata has been widely distributed in China, particularly in Liaoning, Jilin, and Heilongjiang provinces in northeast China, in which it has been used as a traditional herbal medicine for thousands of years to treat various diseases, such as hepatitis and rheumatoid arthritis. A. elata polysaccharides (AEPs) are one of the major active ingredients of A. elata, the monosaccharide composition of which consist primarily of Gal, Glc, Man, Ara, and Rha, with molecular weights ranging from 1.56 × 104 Da to 1.12 × 105 Da. AEPs have attracted worldwide attention owing to their various biological activities, including antioxidant activity, antitumor activity and hepatoprotection. The present review aims to comprehensively summarize the research advances on the polysaccharides isolated from A. elata, including the extraction, separation, physical-chemical properties, structural characteristics, and bioactivities over the past few decades. This review would establish a solid foundation for further development and application in the field of AEPs.

Interplay between traditional Chinese medicine polysaccharides and gut microbiota: The elusive "polysaccharides-bond-bacteria-enzyme" equation

Polysaccharides are one of the most important components of traditional Chinese medicine (TCM) and have been extensively studied for their immunomodulatory properties. The functions and effects of TCM polysaccharides are closely related to the gut microbiota, making the study of their interaction a hot topic in the field of TCM metabolism. This review follows two main inquiries: first, how the gut microbiota breaks down TCM polysaccharides to produce bioactive metabolites; and second, how TCM polysaccharides reshape the gut microbiota as a carbon source. Understanding the interaction mechanism involves a challenging equation of the structural association of TCM polysaccharides with the metabolic activities of the microbiota. This review has meticulously searched, partially organized literature spanning the past decade, that delves into the interaction mechanism between TCM polysaccharides and gut microbiota. It also gives an overview of the complex factors of the elusive "polysaccharides-bond-bacteria-enzyme" equation: the complexity of polysaccharide structures, the diversity of glycosidic bond types, the communal nature of metabolizing microbiota, the enzymes involved in functional degradation by microbiota, and the hierarchical roles of polysaccharide utilization locus and gram-positive PULs. Finally, this review aims to facilitate discussion among peers in the field of TCM microbiota and offers prospects for research in related fields, paving the way for pharmacological studies on TCM polysaccharides and gut microbiota therapeutics, and providing a reference point for further clinical research.

The relationship between polysaccharide structure and its antioxidant activity needs to be systematically elucidated

Polysaccharides have a wide range of applications due to their excellent antioxidant activity. However, the low purity and unclear structure of polysaccharides have led some researchers to be skeptical about the antioxidant activity of polysaccharides. The current reports on the structure-activity relationship of polysaccharides are sporadic, so there is an urgent need to systematically summarize the antioxidant effects of polysaccharides with clear structures and the relationships between the structures to provide a scientific basis for the development and application of polysaccharides. This paper will systematically elucidate the structure-activity relationship of antioxidant polysaccharides, including the molecular weight, monosaccharide composition, glycosidic linkage, degree of branching, advanced conformation and chemical modification. For the first time, the antioxidant activity of polysaccharides is related to their chemical structure through histogram and radar map, and further studies using principal component analysis and cluster analysis. We critically discussed how the source, chemical structure and chemically modified groups of polysaccharides significantly contribute to their antioxidant activity and summarized the current research status and shortcomings of the structure-activity relationship of antioxidant polysaccharides. This review provides a theoretical basis and new perspective for further research on the structure-activity relationship of antioxidant polysaccharides and the development of natural antioxidants.

Improvement of nucleotide content of Cordyceps tenuipes by Schisandra chinensis: fermentation process optimization and application prospects

Nucleotides are important components and the main indicators for judging Cordyceps quality. In this paper, the mixed fermentation process of Schisandra chinensis and Cordyceps tenuipes was systematically studied, and it was proposed that the fermentation products aqueous extract (S-ZAE) had antioxidant activity and anti-AChE ability. Herein, the results of a single factor showed that S. chinensis, yeast extract, inoculum amount, and pH had significant effects on nucleotide synthesis. The fermentation process optimization results were 3% glucose, 0.25% KH2PO4, 2.1% yeast extract, and S. chinensis 0.49% (m/v), the optimal fermentation conditions were 25℃, inoculum 5.8% (v/v), pH 3.8, 6 d. The yield of total nucleotides in the scale-up culture was 0.64 ± 0.027 mg/mL, which was 10.6 times higher than before optimization. S-ZAE has good antioxidant and anti-AChE activities (IC50 0.50 ± 0.050 mg/mL). This fermentation method has the advantage of industrialization, and its fermentation products have the potential to become good functional foods or natural therapeutic agents.

Elucidation of antioxidant activities of intracellular and extracellular polysaccharides from Cordyceps militaris in vitro and their protective effects on ulcerative colitis in vivo

In this study, we extracted the polysaccharides from C. militaris fruiting bodies (CFIPs), mycelial intracellular polysaccharides (CMIPs), and fermentation broth extracellular polysaccharides (CFEPs) to investigate their physicochemical properties, antioxidant capacities, and effects on oxazolone-induced zebrafish ulcerative colitis (UC). Our results revealed differences in monosaccharide composition and surface structure among CFIPs, CMIPs, and CFEPs. The molar ratios of glucose to mannose in CFIPs, glucose to xylose in CMIPs, and xylose to glucose in CFEPs were 7.57: 1.6, 7.26: 1.81, and 5.44: 2.98 respectively. Moreover, CFEPs exhibited significantly (p < 0.05) higher chemical antioxidant capacity compared to CMIPs and CFIPs. Surprisingly, CFEP treatment didn't show a significant effect in protecting against H2O2-induced oxidative damage in RAW 264.7 cells. After 3 d of treatment, the levels of ROS, MDA, and MPO in the CFIPs group exhibited a significant (p < 0.05) reduction by 37.82 %, 68.15 %, and 22.77 % respectively. Additionally, the ACP and AKP increased by 60.33 % and 96.99 %. Additionally, C. militaris polysaccharides (CMPs) were found to effectively improve UC by activating the MyD88/NF-κB signaling pathway in vivo. These findings confirm the distinct physicochemical properties of these three types of CMP and their potential for development into antioxidant-rich anti-inflammatory health foods.

Study on characterization of Bupleurum chinense polysaccharides with antioxidant mechanisms focus on ROS relative signaling pathways and anti-aging evaluation in vivo model

This study explored the structures of three polysaccharides from Bupleurum chinense DC. (BCPRs), and evaluated their antioxidant and anti-aging properties. The HPGPC and ion chromatography analyses revealed that the molecular weights of the BCPRs ranged from 12.05 to 21.20 kDa, and were primarily composed of rhamnose, arabinose, xylose, galactose, glucose and galacturonic acid. Methylation and NMR studies identified 10 PMAAs, establishing the various backbones of BCPRs 1-3. BCPR-3 demonstrated potent antioxidant activities, including DPPH, ABTS, hydroxy, and superoxide radicals scavenging in vitro. At concentrations between 125 and 500 μg/mL, BCPR-3 increased T-AOC, SOD and GSH-Px activities, while decreasing MDA levels in H2O2-induced SH-SY5Y cells. In addition, RNA-seq results indicated that BCPR-3 considerably downregulated the expression of 49 genes and upregulated five genes compared with the control group. KEGG analysis suggested that these differentially expressed genes (DEGs) were predominantly involved in the TNF and PI3K/Akt signaling pathways. Furthermore, in vivo experiment with Drosophila melanogaster showed that BCPR-3 could extend the average lifespan of flies. In conclusion, polysaccharides from B. chinense exhibited potential antioxidant and anti-aging activities, which could be developed as new ingredients to combat oxidative stress damage and slow the aging process.

Optimization of cultural and nutritional conditions to enhance mycelial biomass of Cordyceps militaris using statistical approach

Cordyceps militaris is a fungus with numerous therapeutic properties that has gained worldwide popularity due to its potential health benefits. The fruiting body of this mushroom is highly expensive and takes a longer time to produce, making mycelial a sustainable and cost-effective alternative. The study investigates and optimizes cultural and nutritional conditions to maximize mycelial biomass. The initial optimization was done by the conventional single-factor approach, followed by Plackett-Burman design to screen the most significant variables, with yeast extract, temperature, and glucose being the most significant, contributing 11.58%, 49.74%, and 27.98%, respectively, in mycelial biomass production. These variables were then optimized using response surface methodology (RSM) based on central composite design (CCD). The study observed that temperature and glucose had the highest impact on mycelial biomass, with p-values of 0.0128 and 0.0191, respectively. Under the optimized conditions, temperature 20 °C, glucose 2.5% (w/v), and yeast extract 0.8% (w/v), the maximal yield of mycelial biomass reached 547 ± 2.09 mg/100 mL, which was 1.95-fold higher than the yield in the basal medium. These findings suggest that optimizing the cultural and nutritional conditions can enhance mycelial biomass production of Cordyceps militaris, offering a sustainable and cost-effective source of this valuable fungus.

A review on polysaccharide biosynthesis in Cordyceps militaris

Cordyceps militaris (C. militaris) is an edible parasitic fungus with medicinal properties. Its bioactive polysaccharides are structurally diverse and exhibit various metabolic and biological activities, including antitumor, hypoglycemic, antioxidant, hypolipidemic, anti-inflammatory, immunostimulatory, and anti-atherosclerotic effects. These properties make C. militaris-derived polysaccharides a promising candidate for future development. Recent advancements in microbial fermentation technology have enabled successful laboratory cultivation and extraction of these polysaccharides. These polysaccharides are structurally diverse and exhibit various biological activities, such as immunostimulatory, antioxidant, antitumor, hypolipidemic, and anti-atherosclerotic effects. This review aims to summarize the structure and production mechanisms of polysaccharides from C. militaris, covering extraction methods, key genes and pathways involved in biosynthesis, and fermentation factors that influence yield and activity. Furthermore, the future potential and challenges of utilizing polysaccharides in the development of health foods and pharmaceuticals are addressed. This review serves as a valuable reference in the fields of food and medicine, and provides a theoretical foundation for the study of polysaccharides.

Phosphorylation Modification, Structural Characterization, Antioxidant and DNA Protection Capacities of Polysaccharides from Asarum Sieboldii Miq

Polysaccharide from Asarum sieboldii Miq (ASP) was extracted and five phosphorylation polysaccharides with different degree of substitution were obtained, namely ASPP1, ASPP2, ASPP3, ASPP4, and ASPP5 (ASPPs). The physical and chemical structure and biological activities were studied. The results suggested that the carbohydrate and protein content were reduced while uronic acid was increased after phosphorylation modification. The molecular weight of ASPPs was significantly lower than that of ASP. ASPPs were acidic heteropolysaccharides mainly composed of galacturonic acid, galactose, glucose, fructose, and arabinose. The UV-vis spectrum indicated that the polysaccharides did not contain nucleic acid or protein after modification. The Fourier transform infrared spectrum demonstrated that ASPPs contained characteristic absorption peaks of P=O and P-O-C near 1270 and 980 cm-1 . ASPPs presented a triple helix conformation, but it was not presented in ASP. The scanning electron microscopy analysis showed that the surface topography and particle structure of ASP were different after modification. Compared with ASP, ASPPs enhanced the activity to scavenge DPPH and ABTS free radicals and possessed more protective ability to DNA oxidation caused by OH⋅, GS⋅, and AAPH free radicals. These results suggest that chemical modification is beneficial for the exploitation and utilization of natural polysaccharides.

Efficacy of polysaccharide iron complex in IDA rats: A comparative study with iron protein succinylate and ferrous succinate

Iron deficiency anemia (IDA) is the most common nutrient-related health problem in the world. There is still a lack of comprehensive comparative study on the efficacies of commonly used iron supplements such as polysaccharide iron complex (PIC), iron protein succinylate (IPS) and ferrous succinate (FS) for IDA. In this study, we compared the PIC, IPS and FS efficacies in IDA rats via intragastric administration. The results showed that the three iron supplements had similar efficacies. PIC/IPS/FS at a dose of 15 mg Fe/kg/d for 10 d increased the hematological and serum biochemical parameters to 2.15/2.12/2.18 (Hb), 1.71/1.67/1.69 (RBC), 2.10/2.11/2.12 (HCT), 1.26/1.22/1.22 (MCV), all 1.34 (MCH), 1.15/1.15/1.14 (MCHC), 1.94/1.82/1.91 (SF), 9.75/9.67/9.53 (SI), and 23.30/22.68/21.64 (TS) times, and reduced TIBC to 0.42/0.43/0.44 times, compared to untreated IDA rats. PIC performed slightly better than IPS and FS in restoring MCV level. Meanwhile, the heart, spleen and kidney coefficients reduced to 67%/74%/65% (heart), all 59% (spleen) and 87%/88%/88% (kidney), and the liver coefficient increased to 116%/115%/116%, compared to untreated IDA rats. The liver iron content was found to be more affected by IDA than the spleen iron content. PIC/IPS/FS at 15 mg Fe/kg/d increased organ iron contents to 4.20/3.97/4.03 times (liver) and 1.36/1.24/1.41 times (spleen) within 10 d compared to untreated IDA rats, and PIC-H and FS were slightly better than IPS in restoring spleen iron content. The results of this study can provide useful data information for the comparison of three iron supplements, PIC, IPS and FS.

Antimicrobial, antioxidant, anti-inflammatory, and cytotoxic activities of Cordyceps militaris spent substrate

Cordyceps militaris is a medicinal mushroom and has been extensively used as a traditional medicine in East Asia. After the chrysalis seeds are matured and harvested, the spent substrate of C. militaris still contains active ingredients but is usually discarded as waste. This study aimed to determine the antioxidant and anti-inflammatory activities of C. militaris spent substrate extract and its inhibitory activity on the Malassezia commensal yeasts that can cause dandruff and seborrheic dermatitis. Active substances in the spent substrate of C. militaris were extracted using a hot water extraction method and were used for the determination of antioxidant activity by measuring their ability to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radicals, hydrogen peroxide, and superoxide anions. The ability to inhibit Malassezia was analyzed using the broth microdilution method, and the reparative effect on oxidative damage in HaCaT cells was measured using in vitro cell analysis. Respiratory burst evaluation was used to determine the anti-inflammatory capacity of extracts. Analysis of the Malassezia-inhibiting activity of the extracts showed that the minimum inhibitory concentration was 6.25 mg/mL. The half maximal inhibitory concentration (IC50) values of DPPH, O2-, H2O2 and OH- were 3.845 mg/mL, 2.673 mg/mL, 0.037 mg/mL and 0.046 mg/mL, respectively. In the concentration range of 2 to 50%, the extract was non-toxic to cells and was able to protect HaCaT cells from H2O2 damage. When the volume fraction of the extract was 20.96%, its anti-inflammatory ability reached 50%. These results demonstrated that the extract may be a safe and efficacious source for pharmaceutical or cosmetic applications, with Malassezia-inhibiting, antioxidant and anti-inflammatory activities.

Advances on novel iron saccharide-iron (III) complexes as nutritional supplements

Iron deficiency is prevalent worldwide, and iron supplementation is a promising strategy to address iron needs of the body. However, traditional oral supplements such as ferrous sulfate, ferrous succinate, and ferrous gluconate are absorbed in the form of ferrous ions, leading to lipid peroxidation and side effects due to other reasons. In recent years, saccharide-iron (III) complexes (SICs) as novel iron supplements have aroused attention for the high iron absorption rate and no gastrointestinal irritation at oral doses. In addition, research on the biological activities of SICs revealed that they also exhibited good abilities in treating anemia, eliminating free radicals, and regulating the immune response. This review focused on the preparation, structural characterization, and bioactivities of these new iron supplements, as promising candidates for the prevention and treatment of iron deficiency.

Three acidic polysaccharides derived from sour jujube seeds protect intestinal epithelial barrier function in LPS induced Caco-2 cell inflammation model

Normal intestinal epithelial barrier function plays a key role in the prevention of many diseases such as infectious enteritis, inflammatory bowel disease, obesity, etc. In this study, three novel acidic polysaccharides ZY-2, ZY-3 and ZY-4 were isolated from sour jujube (Ziziphus jujuba Mill. var. Spinosa) seeds and purified by DEAE Sephrose Fast Flow gel. The molecular weight of ZY-2, ZY-3 and ZY-4 was 7.76 kDa, 10.71 kDa and 8.31 kDa respectively, mainly composed of different proportions of mannose, rhamnose, glucose, glucuronic acid, galacturonic acid, galactose, xylose and arabinose. ¹H NMR and Congo red experiment results showed that the three polysaccharides mainly contained both α-type and β-type glycosidic bonds with obvious triple helix structural traits. The polysaccharides could up-regulate the expression levels of occludin and ZO-1 in LPS-induced inflammation Caco-2 cells, and reduce IL-6, IL-8, IL-1β and TNF-α significantly. In conclusion, the acidic polysaccharides from sour jujube seeds exhibited great potential in protection intestinal epithelial barrier function through anti-inflammatory effects.

Preparation, structural analysis and physicochemical properties of the Cordyceps cicadae exopolysaccharide iron complex

In this study, EPS-Fe(III) complexes were synthesized, and their structural characteristics, thermal stability, antioxidant activity and digestive properties were evaluated. The content of iron in the EPS-Fe(III) complex was 6.34 ± 1.43 %. The absorbance bands of EPS and EPS-Fe(III) complexes were easily changed, indicating that iron ions can interact with the hydroxyl or carboxyl groups of EPS. Energy spectrometric analysis showed that a strong iron signal was observed in the EPS-Fe(III) complex. The IC₅₀ values of the EPS-Fe(III) complex for DPPH, hydroxyl radical and ABTS were 1.52 mg/mL, 2.63 mg/mL and 1.20 mg/mL, respectively. Under oxidative stress, EPS-Fe(III) can prolong the lifespan of nematodes through the DAF-16 and SKN-1 pathways. Under the condition of gastric juice and intestinal juice, the iron content released from artificial intestinal juice reached 66 %. In addition, the negative effect of trypsin or polyphenols on the solubility of iron in EPS-Fe(III) digestive solution was lower than that in ferric chloride digestive solution. In conclusion, the EPS-Fe(III) complex can be used as a new type of iron supplement, which has good antioxidant activity, high stability and good water solubility.

Structural Characterization, In Vitro Digestion Property, and Biological Activity of Sweet Corn Cob Polysaccharide Iron (III) Complexes

This study aimed to enhance the utilization value of sweet corn cob, an agricultural cereal byproduct. Sweet corn cob polysaccharide-ron (III) complexes were prepared at four different temperatures (40 °C, 50 °C, 60 °C, and 70 °C). It was demonstrated that the complexes prepared at different temperatures were successfully bound to iron (III), and there was no significant difference in chemical composition; and SCCP-Fe-C demonstrated the highest iron content. The structural characterization suggested that sweet corn cob polysaccharide (SCCP) formed stable β-FeOOH iron nuclei with −OH and −OOH. All the four complexes’ thermal stability was enhanced, especially in SCCP-Fe-C. In vitro iron (III) release experiments revealed that all four complexes were rapidly released and acted as iron (III) supplements. Moreover, in vitro antioxidant, α-glucosidase, and α-amylase inhibition studies revealed that the biological activities of all four complexes were enhanced compared with those of SCCP. SCCP-Fe-B and SCCP-Fe-C exhibited the highest in vitro antioxidant, α-glucosidase, and α-amylase inhibition abilities. This study will suggest using sweet corn cobs, a natural agricultural cereal byproduct, in functional foods. Furthermore, we proposed that the complexes prepared from agricultural byproducts can be used as a potential iron supplement.

Optimization of the Extraction Process and Antioxidant Activity of Polysaccharide Extracted from Centipeda minima

The purpose of this study is to optimize the extraction process and study antioxidant activity of Polysaccharide extracted from Centipeda minima. The Box-Behnken design-response surface methodology was adopted to optimize the extraction process of polysaccharides from Centipeda minima. We purified the crude polysaccharides from Centipeda minima, as well as determined the purity, monosaccharide composition, and molecular weight of the purified fraction. Fourier transform infrared spectrometer (FT-IR) and scanning electron microscopy (SEM) were used to analyze the structural features of the polysaccharides. Further, we investigated the antioxidant activities of different fractions of polysaccharides. Consequently, the results showed that the optimum extraction conditions for polysaccharides were: a liquid-solid ratio of 26 mL/g, extraction temperature of 85.5 °C, and extraction time of 2.4 h. Moreover, the yield of polysaccharides measured under these conditions was close to the predicted value. After purification, we obtained four components of Centipeda minima polysaccharides (CMP). The purity, monosaccharide composition, molecular weight, and structural characteristics of CMP were different, but with similar infrared absorption spectra. CMP exhibited a typical infrared absorption characteristic of a polysaccharide. Besides, CMP displayed good antioxidant activity, with potential to scavenge DPPH radical, hydroxyl radical, and superoxide radical. Therefore, this study provides a reference for future research on the structure and biological activity of CMP, and lays a theoretical foundation for food processing and medicinal development of CMP.

Effects of Exogenous Lanthanum Nitrate on the Active Substance Content and Antioxidant Activity of Caterpillar Medicinal Mushroom Cordyceps militaris (Ascomycetes)

Cordyceps militaris is a medicinal and edible mushroom. Researchers often add exogenous substances to the culture medium to increase the active substance content in C. militaris. However, the effect of earth elements on the active substance content in C. militaris and its antioxidant effects have not been reported. In this study, the active substance content in C. militaris treated with lanthanum nitrate was determined using high-performance liquid chromatography and ultraviolet spectrophotometry, and the effect on the antioxidant capacity of C. militaris after lanthanum nitrate spraying was further explored. The results showed that, in the experimental concentration range, the two concentrations of 10 mg/L and 50 mg/L had a significant influence on the active substance content of C. militaris. When the concentration of lanthanum nitrate was 10 mg/L, the synthesis of pentostatin and cordycepin was promoted. When the concentration of lanthanum nitrate was 50 mg/L, it significantly promoted the synthesis of cordycepin, and the ferric-reducing power and DPPH· scavenging rate of C. militaris treated at this concentration were significantly higher than those of the control group. However, lanthanum nitrate had no significant effect on ergosterol synthesis (P > 0.05). Finally, considering that the residual amount of lanthanum in C. militaris and the residual amount of lanthanum in 50 mg/L lanthanum nitrate-treated C. militaris is within the allowable daily intake of 4.2 mg for humans, the optimal concentration of lanthanum nitrate-treated C. militaris is 50 mg/L.

Structural characterization and biological activities of polysaccharide iron complex synthesized by plant polysaccharides: A review

Iron deficiency anemia can lead to a variety of functional disorders, which is one of the highest incidence of nutrient deficiency diseases. The direct addition of iron to food will not only brings difficulties to the production of products, but also brings damages to human body. In recent years, international studies have shown that polysaccharide iron complex (PIC) not only has a variety of pharmacological activities of polysaccharide itself, but also has the function of supplementing iron, so it is a good iron supplement. With the advantages of good solubility, high iron content, low gastrointestinal irritation and high bioavailability, PIC is an effective iron supplement for iron deficiency anemia and has attracted more and more attention. In this paper, the different preparation methods, structural characterization, biological activities and clinical applications of PIC synthesized by natural polysaccharides from plant were reviewed, in order to provide theoretical basis for the development and application of PIC.

Polysaccharides from Rhizoma Atractylodis Macrocephalae: A Review on Their Extraction, Purification, Structure, and Bioactivities

Rhizoma Atractylodes macrocephala polysaccharide (RAMP), the main bioactive compound extracted from Rhizoma Atractylodes macrocephala (RAM), exhibits various biological activities in in vivo and in vitro methods, such as anti-inflammatory, antioxidant, antitumor, immunomodulatory, hepatoprotective effects, and other functions. This review systematically summarizes the recent research progress on the extraction, purification, structural characteristics, and biological activities of RAMP. We hope to provide a theoretical basis for further research on the application of RAMP in the fields of biomedicine and food.

Physicochemical Characteristics and Antidiabetic Properties of the Polysaccharides from Pseudostellaria heterophylla

This study aimed to investigate the Pseudostellaria heterophylla polysaccharides (PF40) physicochemical and antidiabetic characteristics. The ultraviolet–visible (UV) spectra, Fourier transform infrared radiation (FT-IR) spectra, nuclear magnetic resonance (NMR) spectra, zeta potential, surface characteristics, and conformational and thermal stability properties of PF40 were characterized. X-ray diffraction (XRD) and scanning electron microscopy (SEM), combined with Congo red test, revealed that PF40 powder has mainly existed in amorphous form with triple-helix conformation. The single-molecular structure of PF40 exhibited a multi-branched structure extending from the center to the periphery by scanning probe microscopy (SPM) scanning. The monosaccharide residue of PF40 was an α-pyranoid ring and exhibits good stability below 168 °C. Experimental studies on antidiabetic characteristics found that PF40 could significantly improve STZ-induced intestinal mucosal damage and reduce the apoptosis of villus epithelial cells. PF40 combined with metformin could significantly improve the symptoms of insulin resistance in type 2 diabetes mellitus (T2DM) rats, the molecular mechanism might be through inhibiting the expression of RORγ protein and increasing Foxp3 protein in the jejunum of T2DM rats, and then restoring the STZ-induced imbalance of T helper 17(Th17)/ regulatory T cells (Treg) cells, thereby maintaining intestinal immune homeostasis. Results identified in this study provided important information regarding the structure and antidiabetic characteristics of Pseudostellaria heterophylla polysaccharides, which can contribute to the development of Pseudostellaria heterophylla polysaccharides for industrial purposes in the future.

Structural Elucidation and Activities of Cordyceps militaris-Derived Polysaccharides: A Review

Cordyceps militaris is a parasitic edible fungus and has been used as tonics for centuries. Polysaccharides are a major water-soluble component of C. militaris. Recently, C. militaris-derived polysaccharides have been given much attention due to their various actions including antioxidant, anti-inflammatory, anti-tumor, anti-hyperlipidemic, anti-diabetic, anti-atherosclerotic, and immunomodulatory effects. These bioactivities are determined by the various structural characteristics of polysaccharides including monosaccharide composition, molecular weight, and glycosidic linkage. The widespread use of advanced analytical analysis tools has greatly improved the elucidation of the structural characteristics of C. militaris-derived polysaccharides. However, the methods for polysaccharide structural characterization and the latest findings related to C. militaris-derived polysaccharides, especially the potential structure-activity relationship, have not been well-summarized in recent reviews of the literature. This review will discuss the methods used in the elucidation of the structure of polysaccharides and structural characteristics as well as the signaling pathways modulated by C. militaris-derived polysaccharides. This article provides information useful for the development of C. militaris-derived polysaccharides as well as for investigating other medicinal polysaccharides.

Relationship Between the Structure and Immune Activity of Components From the Active Polysaccharides APS-II of Astragali Radix by Enzymolysis of Endo α-1,4-Glucanase

Astragali Radix polysaccharides (APSs) have a wide range of biological activities. Our preliminary experiment showed that APS-Ⅱ (10 kDa) was the main immunologically active component of APSs. However, the characteristic structure related to activity of APS-Ⅱ needs further verification and clarification. In this study, APS-II was degraded by endo α-1,4-glucosidase. The degraded products with different degrees of polymerization [1–3 (P1), 3–6 (P2), 7–14 (P3), and 10–18 (P4)] were obtained using a polyacrylamide gel chromatography column. The structural features of the different products were characterized by HPGPC, monosaccharide composition, Fourier transform infrared spectrum, GC–MS, nuclear magnetic resonance, and UPLC-ESI-QTOF-MS analysis. Specific immune and non-specific immune cell tests were used to identify the most immunogenic fractions of the products. The backbone of P4 was speculated to be α-D-1,4-linked glucans and rich in C2 (25.34%) and C6 (34.54%) branches. Immune screening experiments indicated that the activity of P4 was better than that of APS-II and the other three components. In this research, the relationship between the structure of APS-Ⅱ and the immune activity from the degradation level of polysaccharides was studied, laying a foundation for the quality control and product development of APSs.

Cordyceps militaris as a Bio Functional Food Source: Pharmacological Potential, Anti-Inflammatory Actions and Related Molecular Mechanisms

Cordyceps militaris (C. militaris) is a medicinal mushroom possessing a variety of biofunctionalities. It has several biologically important components such as polysaccharides and others. The diverse pharmacological potential of C. militaris has generated interest in reviewing the current scientific literature, with a particular focus on prevention and associated molecular mechanisms in inflammatory diseases. Due to rising global demand, research on C. militaris has continued to increase in recent years. C. militaris has shown the potential for inhibiting inflammation-related events, both in in vivo and in vitro experiments. Inflammation is a multifaceted biological process that contributes to the development and severity of diseases, including cancer, colitis, and allergies. These functions make C. militaris a suitable functional food for inhibiting inflammatory responses such as the regulation of proinflammatory cytokines. Therefore, on the basis of existing information, the current study provides insights towards the understanding of anti-inflammatory activity-related mechanisms. This article presents a foundation for clinical use, and analyzes the roadmap for future studies concerning the medical use of C. militaris and its constituents in the next generation of anti-inflammatory drugs.

The polysaccharide-peptide complex from mushroom Cordyceps militaris ameliorates atherosclerosis by modulating the lncRNA-miRNA-mRNA axis

Polysaccharides from mushroom Cordyceps militaris are found to have pleiotropic bioactivities, suggesting a potential role in prevention of atherosclerosis. However, the underlying mechanisms of action are not clear. In this...

Lycium Barbarum Polysaccharide-Iron (III) Chelate as Peroxidase Mimics for Total Antioxidant Capacity Assay of Fruit and Vegetable Food

Quantitative evaluation of the antioxidant capacity of foods is of great significance for estimating food’s nutritional value and preventing oxidative changes in food. Herein, we demonstrated an easy and selective colorimetric method for the total antioxidant capacity (TAC) assay based on 3,3’,5,5’-tetramethyl-benzidine (TMB), hydrogen peroxide (H₂O₂) and synthetic Lycium barbarum polysaccharide-iron (III) chelate (LBPIC) with high peroxidase (POD)-like activity. The results of steady-state kinetics study showed that the K_m values of LBPIC toward H₂O₂ and TMB were 5.54 mM and 0.16 mM, respectively. The detection parameters were optimized, and the linear interval and limit of detection (LOD) were determined to be 2–100 μM and 1.51 μM, respectively. Additionally, a subsequent study of the determination of TAC in six commercial fruit and vegetable beverages using the established method was successfully carried out. The results implied an expanded application of polysaccharide-iron (III) chelates with enzymatic activity in food antioxidant analysis and other biosensing fields.