Co-cultured Lepista sordida and Pholiota nameko polysaccharide-iron(iii) chelates exhibit good antioxidant activity

Synthesis, structural characterization and in vitro digestion stability of a soluble soybean polysaccharide‑zinc chelate

The chelation reaction of soluble soybean polysaccharide (SSPS) with zinc was investigated. Using response surface methodology, the optimum parameters for SSPS-Zn synthesis were obtained: pH 5.3, SSPS-ZnCl2 mass ratio of 9.44:1, reaction temperature 50.44 °C, and reaction time 1.5 h, with the highest zinc content of 24.73 %. Compared with SSPS, SSPS-Zn increased in rhamnogalacturonan content and decreased in that of neutral monosaccharides (Fuc, Ara, Gal, Glu and Xyl). UV-vis spectra indicated that SSPS-Zn was lower than SSPS in protein content. FTIR spectra indicated that CO group of SSPS was bonded to Zn2+. X-ray diffraction spectra demonstrated that SSPS-Zn had higher crystallinity. Congo red reactions showed that SSPS possessed a triple-helix conformation while SSPS-Zn formed an irregular free-coiled conformation. EDX confirmed SSPS-Zn synthesis successfully. TGA curves exhibited that SSPS-Zn required higher temperature to undergo degradation. AFM revealed that SSPS-Zn was clustered while SSPS was filamentous. SEM micrographs showed the cracked fragments on the surface of SSPS-Zn. By in vitro simulation of gastrointestinal digestion, Zn2+ release reached 68.87 % after 2 h digestion. Consequently, the chelation of SSPS with zinc could change structure and provide a basis for research and application of novel zinc supplements.

Preparation and Performance Evaluation of Polysaccharide-Iron Complex of Eucommia ulmoides

An innovative iron supplement crucial for treating iron-deficiency anemia was developed in this study. Polysaccharide was extracted from Eucommia ulmoides leaves using a microwave-assisted hot water method, and subsequently, the polysaccharide-iron complex was synthesized through co-thermal synthesis with FeCl3. The physicochemical properties, structure, and thermal stability of the complex were analyzed using FE-SEM, SEC-MALLS, FT-IR, XRD, and DSC techniques. Furthermore, the antioxidant activity of the polysaccharide-iron complex was evaluated through an experiment in vitro. The results revealed that the polysaccharide-iron complex had an iron content of 6.1% and an average particle size of 860.4 nm. The microstructure analysis indicated that the polysaccharide-iron complex possessed a flaky morphology with smooth and compact surfaces. Moreover, the formation of the Fe3+ complex did not alter the structural framework of the polysaccharide; instead, it enhanced the polysaccharide's thermal stability. Compared to traditional iron supplements, the E. ulmoides-derived polysaccharide-iron complex demonstrated significant antioxidant activity. Therefore, this novel compound exhibits significant potential as a viable iron supplement.

Advances in Polysaccharide Production Based on the Co-Culture of Microbes

Microbial polysaccharides are natural carbohydrates that can confer adhesion capacity to cells and protect them from harsh environments. Due to their various physiological activities, these macromolecules are widely used in food, medicine, environmental, cosmetic, and textile applications. Microbial co-culture is an important strategy that is used to increase the production of microbial polysaccharides or produce new polysaccharides (structural alterations). This is achieved by exploiting the symbiotic/antagonistic/chemo-sensitive interactions between microbes and stimulating the expression of relevant silent genes. In this article, we review the performance of polysaccharides produced using microbial co-culture in terms of yield, antioxidant activity, and antibacterial, antitumor, and anti-inflammatory properties, in addition to the advantages and application prospects of co-culture. Moreover, the potential for microbial polysaccharides to be used in various applications is discussed.

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 ultrasonic-assisted polysaccharide extraction from Hyperici Perforati Herba using response surface methodology and assessment of its antioxidant activity

This study performed a comprehensive investigation of Hyperici Perforati Herba polysaccharide (HPHP) regarding the development and optimization of extraction methods, elucidation of structure and characteristics, and determination of antioxidant activities. An ultrasonic-assisted extraction method, which offered advantages in terms of the extraction yield and energy efficiency, was developed by response surface analysis. The following optimum conditions were determined: a crushing degree at 65 mesh, ultrasonic time at 50 min and temperature of 43 °C. Through enzyme-mediated deproteination via the Sevag method, activated carbon depigmentation, and DEAE-52 and Sephadex G-100 column elution, three HPHPs were obtained, and their monosaccharides mainly included mannose, galactose, glucose and arabinose. The molar weights were 8.347, 1.199 and 22.426 kDa, respectively. The HPHP structures were an amorphous aggregate of spherical-like shapes with a rough surface of pores and crevices, which presented characteristic Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectra of polysaccharides. Their main glucosidic linkage is the α-type configuration. Moreover, HPHPs exhibited strong scavenging activity for DPPH·, ABTS·⁺, OH· and O₂·^- radicals; good ferric reducing power; and effective protection against oxidative damage in human cells. Overall, the results of this work underpinned a fundamental understanding of HPHPs, thus providing a potential antioxidant for further research and development.

Composition analysis and prebiotics properties of polysaccharides extracted from Lepista sordida submerged cultivation mycelium

In this paper, Lepista sordida polysaccharides (LSP) were separated from Lepista sordida (L. sordida) mainly using the Ultrasonic-Micro Wave Synergy Extraction (UMSE) method and purified by graded alcohol precipitation. Three polysaccharide components: 40%-LSP-UMSE, 60%-LSP-UMSE, and 80%-LSP-UMSE were obtained and further analyzed the physicochemical properties, structural characteristics, and antioxidant activity. And the effects on the proliferation of Lactobacillus casei of three polysaccharide components were studied. The characteristic absorption peaks and the β-glycosidic bond of three polysaccharide components were the direct expression at UV 200 nm using UV and FT-IR spectroscopy. The three polysaccharide components were mainly composed of glucose, mannose, galactose, and ribose using high-performance liquid chromatography (HPLC) analysis. The antioxidant activity study revealed that the polysaccharides obtained by the UMSE method had better antioxidant activity compared to the traditional "Hot Water Extraction (HWE)" method. In addition, the polysaccharide components promoted the proliferation of L. casei to some extent. 40%-LSP-UMSE, 80%-LSP-UMSE as the carbon source had better acid production than the control inulin. Three LSP-UMSE used as a carbon source compared with glucose for culturing L. casei could significantly improve its tolerance to bile salts. Results are helpful to develop the bioactive polysaccharides from Lepista sordida and beneficial to develop a unique health and functional product in the future.

Effect of Fe (III), Zn (II), and Cr (III) complexation on the physicochemical properties and bioactivities of corn silk polysaccharide

In this paper, Fe (III), Zn (II), and Cr (III) were used to complex with corn silk polysaccharide (CSP) by classical methods and CSP-Fe, CSP-Zn, and CSP-Cr were successfully synthesized, respectively. The physicochemical properties and structural features were characterized by chemical composition analysis, inductive coupled plasma-mass spectrometry (ICP-MS), ultraviolet-visible (UV-Vis) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, fourier transform infrared (FT-IR) spectroscopy, circular dichroism (CD) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and differential scanning calorimetry (DSC), respectively. The antioxidant activities and inhibitory effects on α-glucosidase of CSP, CSP-Fe, CSP-Zn, and CSP-Cr were compared. The results showed that the Fe (III), Zn (II), and Cr (III) chelation could change the morphology, conformation, thermostability, and biological activities of CSP. CSP-Zn exhibited higher antioxidant activities and inhibition effects on α-glucosidase than CSP, which suggested that it could be considered as a potential candidate for developing an ingredient of functional foods for antidiabetics.