Preparation, structural analysis and antioxidant activities of phosphorylated (1 → 3)-β-d-glucan

Polysaccharides in fruits: Biological activities, structures, and structure-activity relationships and influencing factors-A review

Fruits are a rich source of polysaccharides, and an increasing number of studies have shown that polysaccharides from fruits have a wide range of biological functions. Here, we thoroughly review recent advances in the study of the bioactivities, structures, and structure-activity relationships of fruit polysaccharides, especially highlighting the structure-activity influencing factors such as extraction methods and chemical modifications. Different extraction methods cause differences in the primary structures of polysaccharides, which in turn lead to different polysaccharide biological activities. Differences in the degree of modification, molecular weight, substitution position, and chain conformation caused by chemical modification can all affect the biological activities of fruit polysaccharides. Furthermore, we summarize the applications of fruit polysaccharides in the fields of pharmacy and medicine, foods, cosmetics, and materials. The challenges and perspectives for fruit polysaccharide research are also discussed.

Preparation of a hydrolyzed yeast β-glucan chromium(III) complex and evaluation of its hypoglycemic activity and sub-acute toxicity

Yeast β-glucan (BYG) possesses extremely low solubility that has limited its applications. In this study, we hydrolyzed BYG using snail enzyme to obtain hydrolyzed yeast β-glucan (HBYG) with desirable water solubility and hypoglycemic activity. On the basis of HBYG, HBYG‑chromium(III) complex (HBYG-Cr) was synthesized. The molecular weight of the complex was 4.41 × 104 Da, and the content of trivalent chromium was 8.95 %. The hydroxyl groups of HBYG participated in the coordination and formed the chromium complex. The space conformations of HBYG exhibited remarkable changes after complex formation. HBYG-Cr existed mainly in an amorphous state and presented good dispersibility, and the surface was uneven. The hypoglycemic activity of HBYG-Cr was studied in db/db and C57 mice. The results showed that HBYG-Cr had good hypoglycemic activity. Histopathological studies demonstrated that the liver, kidney, pancreas, and skeletal muscle in the treatment group were significantly improved compared with those in the diabetic model group. The sub-acute toxicity of HBYG-Cr was studied in KM mice and the results indicated that the complex did not cause adverse reactions or toxic side effects. This study broadened the application of yeast β-glucan and provided an important reference for the development of hypoglycemic functional foods and drugs.

Extraction, purification, structural modification, activities and application of polysaccharides from different parts of mulberry

The mulberry plant is a member of the Moraceae family and belongs to the Morus genus. Its entire body is a treasure, with mulberries, mulberry leaves, and mulberry branches all suitable for medicinal use. The main active ingredient in mulberries is mulberry polysaccharide. Studies have shown that polysaccharides from different parts of mulberry exhibit antioxidant, antidiabetic, antibacterial, anti-inflammatory, and blood pressure-lowering properties. There are more studies on the biological activities, extraction methods, and structural characterization of polysaccharides from different parts of mulberry. However, the structural characterization of mulberry polysaccharides is mostly confined to the types and proportions of monosaccharides and the molecular weights of polysaccharides, and there are fewer systematic studies on polysaccharides from different parts of mulberry. In order to better understand the bioactive structure of mulberry polysaccharides, this article discusses the recent research progress in the extraction, separation, purification, bioactivity, structural modification, and application of polysaccharides from different parts of mulberry (mulberry leaves, mulberry fruits, and mulberry branches). It also delves into the pharmacological mechanisms of action of mulberry polysaccharides to provide a theoretical basis for further research on mulberry polysaccharides with a view to their deeper application in the fields of feed and nutraceuticals.

Fungi-derived natural antioxidants

In humans, exogenous antioxidants aid the endogenous antioxidant system to detoxify excess ROS generated during oxidative stress, thereby protecting the body against various diseases and stressful conditions. The majority of natural antioxidants available on the consumer market are plant-based; however, fungi are being recognized as alternative sources of various natural antioxidants such as polysaccharides, pigments, peptides, sterols, phenolics, alkaloids, and flavonoids. In addition, some exogenous antioxidants are exclusively found in fungi. Fungi-derived antioxidants exhibit scavenging activities against DPPH, ABTS, hydroxyl, superoxide, hydrogen peroxide, and nitric oxide radicals in vitro. Furthermore, in vivo models, application of fungal-derived antioxidants increase the level of various antioxidant enzymes, such as catalases, superoxide dismutases, and glutathione peroxidases, and reduce the level of malondialdehyde. Therefore, fungi-derived antioxidants have potential to be used in the food, cosmetic, and pharmaceutical industries. This review summarizes the antioxidant potential of different fungi (mushrooms, yeasts, and molds)-derived natural compounds such as polysaccharides, pigments, peptides, ergothioneine, ergosterol, phenolics, alkaloids, etc.

Ultrasound-assisted enzyme extraction and properties of Shatian pomelo peel polysaccharide

In this study, Shatian pomelo peel was used as the raw material for extracting polysaccharides using hot water extraction (HW) and ultrasonic-assisted enzyme (UVE) methods, respectively. The optimal parameters for extractingShatian pomelo peel polysaccharides (StPP) using the ultrasound-assisted enzymatic method were determined using response surface methodology (RSM). The optimal conditions for the extraction of StPP were as follows: ultrasound power 350 W, ultrasound time 50 min, enzymatic digestion time 50 min, compound enzyme addition 1.5%, and enzymatic digestion temperature 55 °C. The yield of StPP was found to be 30.1310% under these conditions. Comparing the physicochemical properties and antioxidant activity of StPP extracted using different methods, it was observed that ultrasound-assisted enzyme extraction resulted in higher yield, sugar content and glucuronic acid content of StPP compared to traditional hot water extraction. Additionally, StPP extracted by ultrasound-assisted enzyme extraction showed better antioxidant activity. These results suggest that ultrasound-assisted enzymatic extraction is an effective method to enhance the activity of natural polysaccharides.

Preparation and Antioxidant Activity of Acetylated Mung Bean Peel Polysaccharides

Mung bean peel polysaccharides are one of the main active components in mung bean peel. Acetylated mung bean peel polysaccharides were prepared by extracting and acetylating them, and characterized by infrared and ultraviolet methods to preliminarily understand the structural characteristics and activity of acetylated mung bean peel polysaccharides. Acetylation modification can improve the structure of polysaccharides, thereby causing changes in their properties. The product obtained after acetylation modification exhibited new characteristic absorption peaks at 1732 cm-1 , and the scavenging ability of hydroxyl radicals was improved. Therefore, acetylation modification of mung bean peel polysaccharides could enhance the activity by improving the structure, which provided an experimental basis for the application of mung bean peel polysaccharides.

Preparation and analysis of polysaccharide from Solanum tuberdsm

The crude Solanum tuberdsm polysaccharides (STP) were extracted with hot water. In the process of extraction, proteins, pigments, small molecules and salts in the mixture were removed by Sevage reagent, diatomite and distilled water dialysis, respectively. In addition, the process conditions of protein removal by response surface methodology (RSM) were optimized, and the optimum process conditions of Sevage method were established as follows: ultrasound power 350 W, ultrasound time 20 min, deproteinization twice, volume ratio of polysaccharide solution to Sevage reagent 1:1 (mL/mL). Under these conditions, the protein removal rate was 93.14%.

Ultrasound-assisted extraction and analysis of maidenhairtree polysaccharides

The maidenhairtree polysaccharides (MTPs) have important application prospects. So, the extraction, purification, structure, derivatization and biological activities of polysaccharides from leaves, fruits, and testae of maidenhairtree were disscussed. Polysaccharides were extracted by collaborative extraction methods such as ultrasound-assisted extraction and microwave-assisted extraction. The ultrasound-assisted extraction had higher content and higher efficiency. The structural characteristics and structure-activity relationship of maidenhairtree polysaccharides were studied in order to provide theoretical basis and technical support for the further development and utilization of maidenhairtree polysaccharides.

Ultrasound-assisted extraction and characteristics of maize polysaccharides from different sites

Antitumor, antioxidant, hypoglycemic, and immunomodulatory properties are all exhibited by maize polysaccharides. With the increasing sophistication of maize polysaccharide extraction methods, enzymatic method is no longer limited to a single enzyme to extract polysaccharides, and is more often used in combination with ultrasound or microwave, or combination with different enzymes. Ultrasound has a good cell wall-breaking effect, making it easier to dislodge lignin and hemicellulose from the cellulose surface of the maize husk. The "water extraction and alcohol precipitation" method is the simplest but most resource- and time-consuming process. However, the "ultrasound-assisted extraction" and "microwave-assisted extraction" methods not only compensate for the shortcoming, but also increase the extraction rate. Herein, the preparation, structural analysis, and activities of maize polysaccharides were analyzed and discussed.

Ultrasonic-assisted extraction, characteristics and activity of Ipomoea batatas polysaccharide

Ipomoea batatas polysaccharides (IBPs) have many important physiological functions. The optimal extraction conditions were extraction time of 40 min, solid-liquid ratio of 1:8 and ultrasonic power of 240 W. 1D/2D nuclear magnetic resonance (1D/2D NMR) analysis showed that the main chain of IBP-1A was mainly composed of →4)-α-D-Glcp-(1→ and →3, 6)-β-D-Glcp-(1→ residues. In vivo experiments showed that polysaccharide significantly increased the levels of antioxidation-related enzymes and metabolites in older mice. It could significantly relieve oxidative stress injury and delay aging. Therefore, this study provided a new theoretical basis for the development of IBPs as antioxidant food.

Preparation and Analysis of Pueraria lobata Polysaccharides

Pueraria lobata polysaccharides (PLPs) were obtained by a hot water extraction method. Starting from the single factor experiment, the extraction was optimized by response surface methodology, and the following optimal extraction parameters were obtained: the extraction temperature was 84 °C, the liquid-solid ratio was 11 mL/g, the extraction time was 73 min, and the extraction rate of polysaccharides was 8.59%. The Sevag method was used to remove the protein soluble in water and H₂O₂ was used to remove the pigment; then PLPs were precipitated with three times of anhydrous ethanol, soluble salts and other small molecules were removed by dialysis, and finally refined PLPs were obtained by freeze-drying.

Phosphorylated polysaccharides: Applications, natural abundance, and new-to-nature structures generated by chemical and enzymatic functionalization

Polysaccharides are foreseen as serious candidates for the future generation of polymers, as they are biosourced and biodegradable materials. Their functionalisation is an attractive way to modify their properties, thereby increasing their range of applications. Introduction of phosphate groups in polysaccharide chains for the stimulation of the immune system was first described in the nineteen seventies. Since then, the use of phosphorylated polysaccharides has been proposed in various domains, such as healthcare, water treatment, cosmetic, biomaterials, etc. These alternative usages capitalize on newly acquired physico-chemical or biological properties, leading to materials as diverse as flame-resistant agents or drug delivery systems. Phosphorylated polysaccharides are found in Nature and need to be extracted to assess their biological potential. However, they are not abundant, often present complex backbones hard to characterize, and most of them have a low phosphate content. These drawbacks have pushed forward the development of chemical phosphorylation employing a wide variety of phosphorylating agents to obtain polysaccharides with a large range of phosphate content. Chemical phosphorylation requires the use of harsh conditions and toxic, petroleum-based solvents, which hinders their exploitation in the food and health industry. Over the last 20 years, although enzymes are regiospecific catalysts that work in aqueous and mild conditions, enzymatic phosphorylation has been little investigated. To date, only three families of enzymes have been used for the in vitro phosphorylation of polysaccharides. Considering the number of unresolved metabolic pathways leading to phosphorylated polysaccharides, the huge diversity of kinase sequences, and the recent progress in protein engineering one can envision native and engineered kinases as promising tools for polysaccharide phosphorylation.

Structural characterisation and antioxidant activities in vitro and in vivo of a novel polysaccharide from Salvia miltiorrhiza

Polysaccharides have received extensive attention due to their multiple physiological functions, especially their remarkable antioxidant capacity. In this study, a novel acidic polysaccharide (PSMP-2) with a molecular weight (Mw) of 1.28 × 10⁶ Da from Salvia miltiorrhiza Bunge was extracted and purified via DEAE-52 cellulose column and Sephadex G-100 column chromatography. The structure of PSMP-2 was characterised by high-performance gel permeation chromatography (HPGPC), high-performance liquid chromatography (HPLC), Fourier transforms infrared spectroscopy (FT-IR) and methylation analysis. The results showed that PSMP-2 was an acidic heteropolysaccharide composed of rhamnose (Rha) (6.15%), galacturonic acid (GalA) (55.98%), and galactose (Gal) (21.27%) and arabinose (Ara) (16.69%). PSMP-2 contained five major glycosidic linkages, (1→)-linked-Ara, (1→2, 4)-linked-Rha, (1→4)-linked-Gal, (1→6)-linked-Gal, (1→3, 6)-linked-Gal, in a molar ratio of 5.98: 1.45: 72.23: 16.40: 3.94. The IC₅₀ of PSMP-2 on 2, 2-Diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl free radical scavenging ability were 0.991 mg/mL and 4.007 mg/mL, respectively. It could regulate the activity of antioxidant enzymes in vivo and had good antioxidant activity. To sum up, a novel acidic polysaccharide (Mw of 1.28 × 10⁶ Da) with antioxidant activity was isolated from S. miltiorrhiza, and its application prospect in the field of medicine and food was preliminarily revealed.

Yeast Extract: Characteristics, Production, Applications and Future Perspectives

Yeast extract is a product prepared mainly from waste brewer's yeast, which is rich in nucleotides, proteins, amino acids, sugars and a variety of trace elements, and has the advantages of low production cost and abundant supply of raw material. Consequently, yeast extracts are widely used in various fields as animal feed additives, food flavoring agents and additives, cosmetic supplements, and microbial fermentation media; however, their full potential has not yet been realized. To improve understanding of current research knowledge, this review summarizes the ingredients, production technology, and applications of yeast extracts, and discusses the relationship between their properties and applications. Developmental trends and future prospects of yeast extract are also previewed, with the aim of providing a theoretical basis for the development and expansion of future applications.

Ultrasound-assisted extraction and properties of polysaccharide from Ginkgo biloba leaves

Response surface methodology (RSM) was used to optimize the ultrasound-assisted extraction conditions of Ginkgo biloba leaves polysaccharide (GBLP). The optimum extraction conditions for the ultrasound-assisted extraction of GBLP were obtained as liquid to material ratio of 30 mL/g, ultrasonic power of 340 W, and extraction time of 50 min. Under these conditions, the yield of GBLP was 5.37 %. Two chemically modified polysaccharides, CM-GBLP and Ac-GBLP, were obtained by carboxymethylation and acetylation of GBLP. The physicochemical properties of these three polysaccharides were comparatively studied and their in vitro antioxidant activities were evaluated comprehensively. The results showed that the solubility of the chemically modified polysaccharides was significantly enhanced and the in vitro antioxidant activity was somewhat improved. This suggests that carboxymethylation and acetylation are effective methods to enhance polysaccharide properties, but the results exhibited some uncontrollability. At the same time, GBLP has also shown high potential for research and application.

Preparation, characterization, structural analysis and antioxidant activities of phosphorylated polysaccharide from Sanchi (Panax notoginseng) flower

In this study, phosphorylation effects on the monosaccharide composition, structural attributes, morphology and radical-scavenging activities of Sanchi (Panax notoginseng) flower polysaccharides were investigated. Sanchi flower phosphorylated polysaccharides mainly comprised of Man, Rha, GluA, GalA, Glu, Gal and Xyl, but lacked GluN, Rib, Arab and Fuc in their compositions. FTIR analysis of phosphorylated polysaccharides showed an emergence of new absorption peak around spectral region of 1254 cm-1. NMR and FTIR analyses were indicative of the successful phosphorylation of the Sanchi flower polysaccharides. The introduction of phosphate groups into polysaccharides led to the induction of pore-like structures in polysaccharides configuration. Phosphorylation of polysaccharides led to concentration-dependent increasing tendencies in radical-scavenging activities. These findings demonstrated the positive impact of phosphorylation on Sanchi flower polysaccharides, which could potentially be used as a therapeutic agent.

An important polysaccharide from fermentum

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Extraction, structure and modification of polysaccharides from fermentum were summarized.

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Structure-activity relationship and application of polysaccharides from fermentum were reviewed.

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It provided a strong basis for the development and application of polysaccharides from fermentum.

Fermentum is a common unicellular fungus with many biological activities attributed to β-polysaccharides. Different in vivo and in vivo experimental studies have long proven that fermentum β-polysaccharides have antioxidant, anti-tumor, and fungal toxin adsorption properties. However, there are many uncertainties regarding the relationship between the structure and biological activity of fermentum β-polysaccharides, and a systematic summary of fermentum β-polysaccharides is still lacking. Herein, we reviewed the research progress about the extraction, structure and modification, structure–activity relationship, activity and application of fermentum β-polysaccharides, compared the extraction methods of fermentum β-polysaccharide, and paid special attention to the structure–activity relationship and application of fermentum β-polysaccharide, which provided a strong basis for the development and application of fermentum β-polysaccharide.

Feruloyl oligosaccharides, isolated from bacterial fermented wheat bran, exhibit antioxidant effects in IPEC-J2 cells and zebrafish model

Feruloyl oligosaccharides (FOs) were produced by solid-state fermentation of wheat bran using Bacillus subtilis, Bacillus licheniformis, and Saccharomyces cerevisiae, and its antioxidant activity was investigated using IPEC-J2 cells and zebrafish embryo model. Preliminary structure analysis revealed that FOs has an average molecular weight of 11.81 kDa and consists of mannose, ribose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, xylose, arabinose, and fucose. The obtained FOs possess superior reducing power and DPPH and hydroxyl free radical scavenging activities. In IPEC-J2 cells, antioxidant enzymes activities and GSH level were significantly increased, while MDA level was reduced by FOs. Further studies showed that FOs achieved the aforementioned effects by activating Nrf2 signaling pathway. In zebrafish embryo, FOs effectively suppressed ROS production, lipid peroxidation, and cell death by increasing SOD and GSH-Px activities. Our findings suggested that FOs from solid-state fermented wheat bran with mixed bacteria can be used as an antioxidant food additive or drugs.

Preparation, characterization and immunoregulatory activity of derivatives of polysaccharide from Atractylodes lancea (Thunb.) DC

A polysaccharide (ALP-1) extracted from Atractylodes lancea (Thunb.) DC. was carboxymethylated (C-ALP-1), phosphorylated (P-ALP-1) and acetylated (A-ALP-1) to improve its physicochemical properties and bioactivities. The solubility of all derivatives was increased, and the solubility of A-ALP-1 increased to 137.5 mg/mL, which was much higher than the solubility of ALP-1 (15.0 mg/mL). The results of HPSEC-MALLS-RID showed that the molecular weight of polysaccharides was slightly increased after the modification, and the root mean square radius of rotation (Rz) and morphology of polysaccharides in solution were also changed. The scanning electron microscopy (SEM) and X-ray diffraction (XRD) results confirmed that the surface morphology of ALP-1 changed dramatically and the crystallinity decreased after structural modification. From thermal analysis results, the T₅₀ of ALP-1, C-ALP-1, P-ALP-1 and A-ALP-1 were 281.34, 292.14, 333.75 and 298.70 °C, which showed that derivatives had stronger thermal stability than ALP-1. The immunomodulatory activity studies displayed that P-ALP-1 showed the best ability to stimulate RAW264.7 macrophages to release NO, and A-ALP-1 showed the best capacity to stimulate TNF-α and IL-6 releasing. These results indicated that chemical modification could enhance the solubility, the thermal stability and immunomodulatory activity of polysaccharides, which is beneficial for the development and utilization of natural polysaccharides.

Characterization of β-Glucan-Peanut Protein Isolate/Soy Protein Isolate Conjugates and Their Application on Low-Fat Sausage

Polysaccharide-protein conjugates can improve the functional properties and expand the application field. The emulsifying, thermal properties of WSG-PPI conjugates and WSG-SPI conjugates were improved, compared to WSG, PPI and SPI. The Maillard reaction was confirmed by Fourier transform infrared spectroscopy (FT-IR). Circular dichroism (CD) exhibited that the structure of the conjugates was more expanded. Cryo-SEM and AFM demonstrated that the WSG, WSG-PPI and WSG-SPI conjugates had a morphology of a chain. When the conjugates were added as fat substitutes to low-fat sausage, the cooking yield, hardness and chewiness increased. The objective of this research was to study the emulsifying property, thermal property and structural changes of β-glucan-peanut protein isolate (WSG-PPI) conjugates and β-glucan-soy protein isolate (WSG-SPI) conjugates prepared through wet-heated Maillard reaction, and their effect on the texture of low-fat sausage.

Preparation, structure and activity of polysaccharide phosphate esters

Polysaccharides have anti-virus, anti-cancer, anti-oxidation, immune regulation, hypoglycemia and other biological activities. Because of their safety, fewer side effects and other advantages, polysaccharides are considered as ideal raw materials in food and drugs. The biological activity of polysaccharides can be improved by structural modification (such as sulfation, carboxymethylation, phosphorylation, etc.), and even new biological activity can be generated. In this review, the recent advances in the phosphorylation of polysaccharides were reviewed from the perspectives of modification methods, structures, biological activities and structure-activity relationships.

Antioxidant activity of sulfated Porphyra yezoensis polysaccharides and their regulating effect on calcium oxalate crystal growth

The nucleation, growth and aggregation of calcium oxalate (CaOx) crystals and the oxidative damage of renal tubular epithelial cells are the key factors to induce kidney stones. In this study, degraded Porphyra yezoensis polysaccharide (PYP0) with 14.14% sulfate group (-OSO₃^-) content was modified via the sulfur trioxide-pyridine method to obtain three kinds of sulfated P. yezoensis polysaccharides (PYPs), namely, PYPS1, PYPS2, and PYPS3, with -OSO₃^- group contents of 17.11%, 20.28%, and 27.14% respectively. Fourier transform infrared spectroscopy, ¹H NMR, and ¹³C NMR analyses showed that the -OSO₃^- groups replaced the hydroxyl groups at the C2, C4, and C6 positions on (1 → 3)-linked β-D-galactose, the basic structural skeleton unit of PYP0. The antioxidant activity of the PYPSs increased after sulfation, and their scavenging capacity for OH and DPPH free radicals was enhanced with the increase in their -OSO₃^- group content. Calcium oxalate (CaOx) crystal growth experiments showed that sulfated PYPs promoted the conversion of the thermodynamically stable and sharp CaOx monohydrate (COM) crystals into the thermodynamically unstable and round CaOx dihydrate crystals. With the increase in the -OSO₃^- group content of the polysaccharides, the concentration of soluble Ca²⁺ ions in the supernatant increased and the amount of CaOx precipitate decreased. PYPs were nontoxic to human kidney proximal tubular epithelial cells (HK-2) and could protect HK-2 from oxidative damage caused by nano-COM and reduce the level of reactive oxygen species in cells. PYPS3, which had the highest degree of sulfation, had the best protective capability. The results of this work showed that sulfation improved the biological activity of PYPs. This study could provide inspiration for the development of new drugs for the prevention and treatment of kidney stones.

Phosphorylation of polysaccharides: A review on the synthesis and bioactivities

Polysaccharides are macromolecules obtained from a wide range of sources and are known to have diverse biological activities. The biological activities of polysaccharides depend on their structure and physicochemical properties, including water solubility, monosaccharide composition, degree of branching, molecular structure, and molecular weight. Phosphorylation is a commonly used chemical modification method that improves the physicochemical properties of native polysaccharides, thus enhancing their biological activity, or even imparting novel biological activity. Therefore, phosphorylated polysaccharides have attracted increasing attention owing to their antioxidant, antitumor, antiviral, immunomodulatory, and hepatoprotective effects. In this review, we have discussed recent advances in the phosphorylation of polysaccharides, and the methods used for phosphorylation, structural characterization, and determination of biological activities, to provide a theoretical basis for the use of polysaccharides. The structure-activity relationship of phosphorylated polysaccharides and their use in the food and pharmaceutical industries needs to be further studied.

A comprehensive review on α-D-Glucans: Structural and functional diversity, derivatization and bioapplications

Glucans are the most abundant natural polysaccharides across the living kingdom with tremendous biological activities. Now a days, α-D-glucans are gaining importance as a prebiotics, nutraceuticals, immunostimulants, antiproliferative agents and biodegradable polymers in pharmaceutical and cosmetic sectors. A wide variety of bioresources including bacteria, fungi, lichens, algae, plants and animals produce α-D-glucans either as an exopolysaccharide (EPS) or a cell wall component or an energy storage polymer. The α-D-glucans exhibit great structural and functional diversity as the type of linkage and percentage of branching dictate the functional properties of glucans. Among the different linkages, bioactivities are greatly confined to the α-D-(1 → 3) linkages whereas starch and other polymers consisting of α-D-(1 → 4) (1 → 6) linkages are specific for food and pharmaceutical applications. However, the bioactivities of the α-D-(1 → 3) glucans in native form is limited mainly due to their hydrophobic nature. Hence several derivatization techniques have been developed to improve the bioavailability as well as bioactive features such as antiviral, antimicrobial, anti-inflammatory, antioxidant, immunomodulatory and antitumor properties. Though, several reports have presented about α-D-glucans, still there is an ambiguity in terms of their structure among different natural sources and moreover no comprehensive information was available on their derivatization techniques and application potential. Therefore, the present review summarizes distinct description on diverse sources, type of linkages, derivatization techniques as well as the application potential of the native and modified α-D-glucans.

Preparation and Characterization of Fish Skin Collagen Material Modified with β-Glucan as Potential Wound Dressing

Collagen possesses unique properties, e.g., biocompatibility, biodegradability, and non-toxicity. However, collagen material degrades too quickly and has low mechanical properties. One of the methods of polymers' modification is mixing them to obtain blends. In this study, the influence of β-glucan for collagen material was analyzed. The interaction between the functional groups of the polymer was analyzed by ATR-FTIR (attenuated total reflection-fourier transform infrared) spectroscopy. The influence of β-glucan on mechanical properties was evaluated. The surface properties of materials were assessed using contact angle measurements and the topography of materials was evaluated by AFM (atomic force microscope). The structure of materials was analyzed according to SEM (scanning electron microscopy) pictures. Moreover, the DPPH-free radicals' scavenging ability and biocompatibility against erythrocytes and HaCaT cells were evaluated. Collagen and β-glucan were bound together by a hydrogen bond. β-glucan addition increased the roughness of the surface of the film and resulted in a more rigid character of the materials. A small addition of β-glucan to collagen provided a more hydrophilic character. All the materials could swell in in vitro conditions and showed antioxidant activity. Materials do not cause erythrocyte hemolysis. Finely, our cytotoxicity studies indicated that β-glucan can be safely added at small (10% or less) quantity to collagen matrix, they sufficiently support cell growth, and the degradation products of such matrices may actually provide some beneficial effects to the surrounding cells/tissues.

Preparation, activity, and antioxidant mechanism of rice bran polysaccharide

Preparation, activity, and mechanism of rice bran polysaccharide were investigated and discussed.

Structural characterization of Lanzhou lily (Lilium davidii var. unicolor) polysaccharides and determination of their associated antioxidant activity

BACKGROUD

The Lanzhou lily (Lilium davidii var. unicolor) is the only Lilium species that is used for both culinary and medicinal purposes in China. Its bulbs contain various bioactive substances, such as polysaccharides, saponins and colchicine. Lanzhou lily polysaccharides are known to have anti-immunity, anti-tumor and anti-oxidation functions.

RESULTS

The present study used a Box-Behnken design to optimize the ultrasound-assisted extraction of Lanzhou lily polysaccharides. Compared to other enzymes, trypsin significantly increased the polysaccharide yields, whereas the protein content of polysaccharides extracted with trypsin was the lowest. Monosaccharide mainly includes glucose (> 50%) and mannose (> 10%). 1,1-Diphenyl-2-picrylhydrazyl radical scavenging activity, chelating activity, total antioxidant capacity and hydroxyl radical scavenging activity of Lanzhou lily polysaccharides extracted with trypsin were stronger than those extracted without enzymes (control). Structural characteristics of Lanzhou lily polysaccharides extracted with trypsin and extracted without enzymes were characterized by scanning electron microscopy and nuclear magnetic resonance spectroscopy. When water extracted polysaccharide and trypsin extracted polysaccharide concentrations were 200 μg mL^-1 , Raw264.7 proliferation rates were 101.69% and 159.41%, respectively.

CONCLUSION

The Lanzhou lily polysaccharide was identified as α-(1 → 6)-d-glucan. Consequently, the effects of both potential antioxidant and proliferative activity of trypsin are significant. © 2020 Society of Chemical Industry.

The influence of traditional and new processing technologies on the structure and function of food polysaccharide

Food processing is the method of transforming raw materials into food or food into other forms through physical or chemical technology and is an important means to extend the shelf life of food. The influence of processing technology on the structure and functional characteristics of polysaccharide was analyzed for the three aspects of dehydration processing technology, hot processing technology and new processing technology to provide reference for prolonging the shelf life of food and protecting its nutritional value.

The antioxidant activities in vivo of bitter gourd polysaccharide

The antioxidant activities of polysaccharide from bitter gourd were studied. It was found that bitter gourd polysaccharide could significantly increase SOD and CAT contents in serum, liver and brain of mice, and reduce MDA levels in serum, liver and brain to a certain extent in vivo. So, bitter gourd polysaccharide should be a potential antioxidant.