Structural, rheological properties and antioxidant activities of polysaccharides from mulberry fruits (Murus alba L.) based on different extraction techniques with superfine grinding pretreatment

Systematic preparation of animal-derived glycosaminoglycans: Research progress and industrial significance

Impurities and isomerized polysaccharides affect the analytical accuracy of glycosaminoglycans (GAGs) structure and bioactivity, hindering their application in food and medicine. Preparing homogeneous GAGs components is essential for exploring structure-potency relationships and facilitating industrial production. This review primarily summarizes research on animal-derived GAGs preparation over the past five years, standardizing the preparation process into four operational units: pre-extraction treatment, extraction of crude polysaccharides, refinement of crude polysaccharides, and separation of GAGs components. Analyzed for scientific research and industrial production, the principles and application conditions of traditional means and novel techniques to preparing GAGs are comprehensively emphasized, exploring the effects of different treatments on biological activity and structure. Current challenges and development trends are illuminated. This review aims to lay a foundation for the in-depth study of GAGs structure, bioactivity, and function, providing theoretical references for the comprehensive utilization of animal raw materials and the development of animal polysaccharide deep-processing industries.

Structural characterization and anti-weightless bone loss activity of an anionic polysaccharide from Dictyophora indusiata

This study explores the extraction and purification of polysaccharides from Dictyophora indusiata (D. indusiata) with its antioxidant and anti-weightlessness bone loss properties. An anionic polysaccharide (SADIP) with a molecular weight of 13.42 kDa was isolated and purified from D. indusiata. SADIP consists of a glucose-based sugar chain backbone. Its backbone consists of glycosidic linkages of →4)-α-D-Glcp-(1 → and →4)-β-D-Glcp-(1→, with sulfate groups attached at the O-6 position of →4)-β-D-Glcp-(1 → residues. Side chains were α-D-Glcp-(1 → 6)-α-D-Glcp-(1 → linked at C-6 position of →4,6)-α-D-Glcp-(1 → through O-6 bonds. In vitro, SADIP scavenged up to 99.32 ± 0.24 % of 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) radicals and 76.72 ± 0.34 % of hydroxyl radicals. In vivo, SADIP reduced malondialdehyde (MDA) levels induced by weightlessness and increased low levels of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) caused by weightlessness. Additionally, three-point mechanical bending tests and Micro-CT analysis demonstrated that SADIP has ability to alleviate bone loss induced by weightlessness. This study provides a theoretical foundation for the rational developmation of D. indusiata resources.

Chemical structure and prebiotic activity of a Dictyophora indusiata polysaccharide fraction

This study aimed to investigate the chemical structure and prebiotic activity of a Dictyophora indusiata polysaccharide fraction DIP0p. Our results indicated that DIP0p belongs to a heteropolysaccharide composed of glucose, galactose, mannose and xylose, accounting for 53.25 %, 24.18 %, 19.19 % and 3.37 %, respectively. Methylation and NMR results suggested that the main glycosidic bonds of DIP0p is →3)-Glcp-(1 → with →4)-Glcp-(1→, →3,4)-Glcp-(1→, →3,4)-Galp-(1 → and →6)-Manp-(1 → branches. In addition, DIP0p increased the abundance of benificial bacteria during the in vitro fecal fermentation, including Phascolarctobacterium, Parabacteroides and Bifidobacterium. It is remarkable that DIP0p improved the level of acetic acid, propionic acid, and butyric acid of the fermentation system, which were 1.31, 1.52, and 2.64 folds higher than the Controls, respectively. In summary, this study comprehensively analyzed the structure and probiotic activity of DIP0p, which providing a theoretical basis for the development of the functional foods.

Effect of Planting Systems on the Physicochemical Properties and Bioactivities of Strawberry Polysaccharides

Suitable planting systems are critical for the physicochemical and bioactivities of strawberry (Fragaria × ananassa Duch.) polysaccharides (SPs). In this study, SPs were prepared through hot water extraction, and the differences in physicochemical characteristics and bioactivities between SPs derived from elevated matrix soilless planting strawberries (EP-SP) and those from and conventional soil planting strawberries (GP-SP) were investigated. A higher extraction yield was observed for EP-SP (5.88%) than for GP-SP (4.67%), and slightly higher values were measured for the average molecular weight (632.10 kDa vs. 611.88 kDa) and total sugar content (39.38% vs. 34.92%) in EP-SP. In contrast, a higher protein content (2.12% vs. 1.65%) and a more ordered molecular arrangement were exhibited by GP-SP. Monosaccharide composition analysis revealed that EP-SP contained higher levels of rhamnose (12.33%) and glucose (49.29%), whereas GP-SP was richer in galactose (11.06%) and galacturonic acid (19.12%). Thermal analysis indicated only minor differences in decomposition temperatures (approximately 225-226 °C) and thermal stability between the samples. However, GP-SP showed a higher enthalpy change (ΔHg = 18.74 J/g) compared to EP-SP (13.93 J/g). Biological activity assays revealed that GP-SP generally exerted stronger non-enzymatic glycation inhibition at both early and final stages (IC50: 7.47 mg/mL vs. 7.82 mg/mL and 11.18 mg/mL vs. 11.87 mg/mL, respectively), whereas EP-SP was more effective against intermediate α-dicarbonyl compounds (maximum inhibition of 75.32%). Additionally, GP-SP exerted superior α-glucosidase inhibition (IC50 = 2.4583 mg/mL), in line with kinetic and fluorescence quenching analyses showing a higher enzyme-substrate complex binding affinity (Kis = 1.6682 mg/mL; Ka = 5.1352 × 105 M-1). Rheological measurements demonstrated that EP-SP solutions exhibited a pronounced increase in apparent viscosity at higher concentrations (reaching 3477.30 mPa·s at 0.1 s-1 and 70 mg/mL) and a stronger shear-thinning behavior, while GP-SP showed a comparatively lower viscosity and lower network order. These findings suggest that different planting systems significantly affect both the molecular structures and functionalities of SPs, with GP-SP demonstrating enhanced hypoglycemic and anti-glycation properties. It is therefore recommended that suitable planting systems be selected to optimize the functionality of plant-derived polysaccharides for potential applications in the food and pharmaceutical industries.

A salt/salt aqueous two-phase system based on pH-switchable deep eutectic solvent for the extraction and separation of mulberry polysaccharides

With the aim of expanding the potential application scope of mulberries, eleven pH-switchable deep eutectic solvents were screened for the ultrasonic-assisted extraction of mulberry polysaccharides, and a salt/salt aqueous two-phase system was constructed for the efficient separation of mulberry polysaccharides by regulating the system pH. DES-9 (tetraethylammonium chloride: octanoic acid molar ratio = 1: 2) with a critical response pH value of approximately 6.1 was concluded to be the best extraction solvent for extracting mulberry polysaccharides. A maximum polysaccharide extraction yield of 270.71 mg/g was obtained under the optimal conditions. The maximum polysaccharide extraction efficiency was 78.09 % for the pH-driven tetraethylammonium chloride/K2HPO4 aqueous two-phase system. An acidic β-pyran mulberry polysaccharide with a low-molecular weight of 9.26 kDa and a confirmed monosaccharide composition were obtained. This efficient and environmentally friendly polysaccharide separation method offers a new approach for the efficient extraction and utilization of other plant polysaccharides.

Physicochemical characteristics of dietary fiber polysaccharides extracted from Murraya koenigii leaves and their functional role on gut homeostasis

Dietary fiber (DF) is an indigestible carbohydrate in plant foods that supports various physiological functions. This study aimed to extract the soluble and insoluble dietary fiber (DF) from the curry leaves and investigate their physicochemical properties as well as their functional role in the homeostasis of the gut microbiome. The study observed that insoluble-DF (IDF) yielded higher amounts than soluble-DF (SDF) across alkali, acid, and water extraction methods. Acid-extracted SDF showed the highest polysaccharide content (91.58 ± 1.53 %). Among IDFs, alkali-extracted IDF showed the highest polysaccharide content (81.93 ± 1.94 %). Glucose, arabinose, and xylose were identified as major monosaccharides. IDF had a larger particle size (463.5 ± 14.2 μm) compared to SDF (1.23 ± 15.55 μm), which influenced its physicochemical properties. IDF displayed better oil-holding capacity, while SDF showed superior water-holding capacity, potentially impacting glucose diffusion and cholesterol micelle formation. Furthermore, SDF and IDF promoted the growth of beneficial gut bacteria and increased production of short-chain fatty acids, which play critical roles in physiological regulation. Acid-extracted SDF restored gut homeostasis by increasing species richness and diversity, predominantly increasing beneficial bacteria and reducing pathogenic bacteria in LPS-induced dysbiotic mice. This study reveals the impact of extraction methods on the physicochemical and functional properties of curry leaves-DF, underscoring its promise as a functional food for gut health.

Immunomodulatory properties of polysaccharide extract samples from Cyanobacterium sp. Rippka B-1200

Cyanobacteria are most abundant in aquatic systems and can grow in freshwater, saline or brackish water, and cold/hot springs. Cyanobacteria have attracted considerable research attention in the last decade as a potential source of numerous biological products in large quantities, such as biofuels, pigments, polyunsaturated fatty acids, nutraceuticals, enzymes, and polysaccharides. Unlike most plant and fungal polysaccharides, the chemical composition, immunomodulatory activity, and molecular mechanisms of action of Cyanobacterium sp. Rippka B-1200 polysaccharides have been studied much less. The complexity of their primary structure due to the high variability of monosaccharides, their diverse bonds, the presence of substituents and high viscosity made detailed structural studies of cyanobacterial polysaccharides rare, which determines the need for analysis of cyanobacteria biomass components to identify active metabolites with promising biological activity. The aim of this study was to investigate the immunomodulatory properties of polysaccharides from Cyanobacterium sp. Rippka B-1200. Pharmacological and nutraceutical value of Cyanobacterium sp. Rippka B-1200 has been set, defining our study's scientific novelty. As a result, the molecular weight of immunoactive polysaccharide (6.0-8.0 kDa) was determined. The analysis shows that endopolysaccharide samples at a concentration of 300 mg/kg showed no significant immunomodulatory effect (1.60 ± 0.15 mg/g), and the thymus mass index of animals in the experimental group was comparable to that of the control group in which animals were immunosuppressed with cyclophosphamide (1.15 ± 0.24 mg/g). When exopolysaccharide samples were used at a concentration of 600 mg/kg, the thymus mass index of animals in the experimental group (3.60 ± 0.32 mg/g) was statistically comparable to that of the control group (without polysaccharide) in which immunosuppression was not induced (thymus index was 3.70 ± 0.25 mg/g). It was found that endopolysaccharide samples at a concentration of 600 mg/kg also exhibited high immunomodulatory activity. When Cyanobacterium sp. Rippka B-1200 endopolysaccharide samples were used, no internal organ changes were observed in experimental animals after immunosuppression. The empirical results presented in the study may find application in the development of both pharmaceutical and cosmetic products.

Preparation of soybean isolate protein/xanthan gum/agar-Lycium ruthenicum anthocyanins intelligent indicator films and its application in mutton preservation

The preparation of intelligent indicator films containing anthocyanins and their utilization for real-time monitoring of meat freshness represents a prominent research topic of food packaging. In this study, anthocyanins (ALR) were extracted from Lycium ruthenicum (LR) using solvent extraction. Subsequently, these anthocyanins were incorporated into films composed of soybean isolate protein (SPI), xanthan gum (XG) and agar, resulting in SPI/XG/Agar-ALR pH-responsive intelligent indicator films. The physical properties, structural characterization and application in mutton preservation were evaluated to identify the intelligent indicator films with the optimal addition ratio of ALR. The results indicated that the SPI/XG/Agar-5 % films exhibited exceptional performance in terms of thickness, mechanical properties, water vapor transmission rate, oxygen transmission rate and light transmission rate. Scanning electron microscope observations revealed that the SPI/XG/Agar-5 % films possessed a smooth and flat surface, while fourier transform infrared spectroscopy analysis confirmed their excellent compatibility. The DPPH radical scavenging rate of the SPI/XG/Agar-5 % film reached 80.75 ± 0.63 %. When applied to the preservation of mutton, the SPI/XG/Agar-5 % film significantly extended the shelf life and effectively monitored the freshness of the meat. This study not only broadens the application scope of Lycium ruthenicum anthocyanins but also provides a foundation for the development of smart packaging materials.

Research progress on extraction techniques, structure-activity relationship, and biological functional mechanism of berry polysaccharides: A review

In recent years, polysaccharides extracted from berries have received great attention due to their various bioactivities. However, the preparation and application of berry polysaccharides have been greatly limited due to the lack of efficient extraction techniques, unclear structure-activity relationships, and ambiguous functional mechanisms. This review discusses the technological progress in solvent extraction, assisted extraction, critical extraction, and combination extraction. The structure-activity relationship and functional mechanism (antioxidation, hypoglycemic, immunoregulation etc.) of berry polysaccharides are reviewed. After systematic exploration, we believe that industrial production is more suitable for using efficient and low-cost extraction methods, such as ultrasonic assisted extraction and microwave assisted extraction. And some of the bioactivities (antioxidant activity, hypoglycemic activity, etc.) of berry polysaccharides are closely related to their structure (molecular weight, monosaccharide composition, branching structure, etc.). Besides, berry polysaccharides exhibit bioactivities by regulating enzyme activity, cellular metabolism, gene expression, and other pathways to exert their effects on the body. These findings indicate the potential of berry polysaccharides as functional foods and drugs. This paper will contribute to the preparation, bioactivity research, and application of berry polysaccharides.

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.

Effects of Different Drying Methods on the Structural Characteristics and Multiple Bioactivities of Rosa roxburghii Tratt Fruit Polysaccharides

Drying conditions significantly impact the compositions and microstructures of polysaccharides, leading to various effects on their chemical characteristics and bioactivities. The objective of this study was to investigate how different industrial drying techniques, i.e., hot air drying, infrared drying, microwave vacuum drying, and freeze drying, affect the structural properties and biological activities of polysaccharides extracted from Rosa roxburghii Tratt fruit (RRTP). Results revealed that these drying methods significantly altered the extraction yield, molecular weights, monosaccharide ratios, contents of uronic acid and total sugars, gelling properties, particle sizes, thermal stability, and microstructures of RRTPs. However, the monosaccharide composition and functional groups of polysaccharides remained consistent across the different drying techniques. Biological activity assays demonstrated that RRTPs, particularly those processed through microwave vacuum drying (MVD-RRTP), exhibited excellent anti-linoleic acid oxidation, robust anti-glycosylation effects, and significant α-glucosidase inhibition in vitro. The outcomes of this research demonstrate that microwave vacuum drying serves as an effective pre-extraction drying method for RRTPs, enhancing their biological activities. This technique is particularly advantageous for preparing RRTPs intended for use in functional foods and pharmaceuticals, optimizing their health-promoting properties for industrial applications.

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.

Natural polysaccharides and their derivatives targeting the tumor microenvironment: A review

Polysaccharides have gained attention as valuable supplements and natural medicinal resources, particularly for their anti-tumor properties. Their low toxicity and potent anti-tumor effects make them promising candidates for cancer prevention and treatment. The tumor microenvironment is crucial in tumor development and offers potential avenues for novel cancer therapies. Research indicates that polysaccharides can positively influence the tumor microenvironment. However, the structural complexity of most anti-tumor polysaccharides, often heteropolysaccharides, poses challenges for structural analysis. To enhance their pharmacological activity, researchers have modified the structure and properties of natural polysaccharides based on structure-activity relationships, and they have discovered that many polysaccharides exhibit significantly enhanced anti-tumor activity after chemical modification. This article reviews recent strategies for targeting the tumor microenvironment with polysaccharides and briefly discusses the structure-activity relationships of anti-tumor polysaccharides. It also summarises the main chemical modification methods of polysaccharides and discusses the impact of chemical modifications on the anti-tumor activity of polysaccharides. The review aims to lay a theoretical foundation for the development of anti-tumor polysaccharides and their derivatives.

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.

Effects of physical method and enzymatic hydrolysis on the properties of soybean fiber-rich stabilizer for oil in water emulsions

BACKGROUND

Okara is a by-product from the soybean industry and an abundant resource of insoluble soybean fiber (ISF). ISF with various properties could be obtained by different extraction methods. It is an attractive option to utilize okara by taking advantage of ISF as an emulsifier or stabilizer.

RESULTS

Compared with the untreated ISF (ISFUT ), superfine grinding reduced the particle size and viscosity of ISF (ISFSG ). Steam explosion increased the water solubility from 17.5% to 51.7% but decreased the water holding capacity and swelling capacity of ISF (ISFSE ) from 15.0 and 14.0 g/g to 4.2 and 3.3 g/g, respectively. Emulsions prepared by ISFUT and ISFSG before or after enzymatic hydrolysis presented large oil droplets and were unstable. Although emulsions prepared by ISFSE after enzymatic hydrolysis (ISFSE-E ) showed flocculation, the volume-weighted average diameter (19.7 μm) were the smallest while the viscosity and viscoelastic modulus were the highest, and exhibited excellent physical stability during storage.

CONCLUSION

ISF obtained by physical and hydrolysis treatment displayed diverging physicochemical properties while ISF prepared by steam explosion-enzymatic hydrolysis presented the best potential to stabilize emulsions. The present study could provide novel information about the utilization of okara by the application of ISF as an emulsifier or stabilizer. © 2023 Society of Chemical Industry.

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

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

Extraction of Ampelopsis japonica polysaccharides using p-toluenesulfonic acid assisted n-butanol three-phase partitioning: Physicochemical, rheological characterization and antioxidant activity

Polysaccharides as the biopolymers are showing various structural and modulatory functions. Effective separation of carbohydrate structures is essential to understanding their function. In this study, we choose an efficient organic acid in combination with recyclable organic solvent three-phase partitioning technology for the simultaneous extraction of polysaccharides from Ampelopsis japonica (AJPs) to ensure the integrity of linear and branched polysaccharide. The monosaccharide composition, glycosidic linkage information, structural and physicochemical analyses and associations with antioxidant activities were extensively analyzed. Synergistic extraction was compared with the conventional hot water extraction method and the results showed that AJPs-HNP exhibited better elastic properties and excellent antioxidant activity. Correlation analysis confirmed that the antioxidant activity of AJPs was significantly correlated with relative molecular weight, uronic acid content and terminal glycoside linkage molar ratios. The collaborative processing has significantly improved the utilization potential of AJPs and provides a sound theoretical foundation for the effective extraction and separation of polysaccharides. Overall, this work provides systematic and comprehensive scientific information on the physicochemical, rheological and antioxidant properties of AJPs, revealing their potential as natural antioxidants in the functional food and pharmaceutical industries.

Separation of polysaccharides from Lycium barbarum L. by high-speed countercurrent chromatography with aqueous two-phase system

The traditional method for isolation and purification of polysaccharides is time-consuming. It often involves toxic solvents that destroy the function and structure of the polysaccharides, thus limiting in-depth research on the essential active ingredient of Lycium barbarum L. Therefore, in this study, high-speed countercurrent chromatography (HSCCC) and aqueous two-phase system (ATPS) were combined for the separation of crude polysaccharides of Lycium barbarum L. (LBPs). Under the optimized HSCCC conditions of PEG1000-K2HPO4-KH2PO4-H2O (12:10:10:68, w/w), 1.0 g of LBPs-ILs was successfully divided into three fractions (126.0 mg of LBPs-ILs-1, 109.9 mg of LBPs-ILs-2, and 65.4 mg of LBPs-ILs-3). Moreover, ATPS was confirmed as an efficient alternative method of pigment removal for LBPs purification, with significantly better decolorization (97.1 %) than the traditional H2O2 method (88.5 %). Then, the different partitioning behavior of LBPs-ILs in the two-phase system of HSCCC was preliminarily explored, which may be related to the difference in monosaccharide composition of polysaccharides. LBPs-ILs-1 exhibited better hypoglycemic activities than LBPs-ILs-2 and LBPs-ILs-3 in vitro. Therefore, HSCCC, combined with aqueous two-phase system, was an efficient separation and purification method with great potential for separating and purifying active polysaccharides in biological samples.

Preparation and characterization of soluble dietary fiber from tiger nut residues, showing enhanced antioxidant activity and metal-ion-binding properties

To improve the utilization of soluble dietary fiber (SDF) from tiger nut residues, the response surface methodology was used to optimize the conditions of superfine grinding to produce SDF with antioxidant and metal-ion-binding properties. The yield was increased (30.56%) and the average particle diameter of SDF was decreased (D50: 32.80 μm) under the optimal conditions (a proportion of grinding medium of 100%, a feeding mass of 0.90 kg, a grinding time of 20 min, and a moisture content of 8.00%). In addition, superfine grinding substantially modified the surface morphology and increased the SDF content and the proportion of monosaccharides by decreasing the molecular weight. Moreover, superfine grinding remarkably enhanced the in vitro antioxidant activities (ABTS+, DPPḤ, and ·OH) of the SDF, which also exhibited favorable metal-ion-binding properties (Ca2+, Zn2+, and Co2+). These results suggest that superfine grinding can be used as a technique to modify dietary fiber to manufacture functional SDF.

Research on the Impact of Deep Eutectic Solvent and Hot-Water Extraction Methods on the Structure of Polygonatum sibiricum Polysaccharides

Deep eutectic solvent (DES) and hot-water extraction (HWE) methods were utilized to extract polysaccharides from Polygonatum sibiricum, referred to as DPsP and WPsP, respectively. The extracted polysaccharides were purified using the Superdex-200 dextran gel purification system, resulting in three components for each type of polysaccharide. The structures of these components were characterized. The molecular weight analysis revealed that DPsP components had slightly larger molecular weights compared with WPsP, with DPsP-A showing a slightly higher dispersity index and broader molecular weight distribution. The main monosaccharide components of both DPsP and WPsP were mannose and glucose, while DPsP exhibited a slightly greater variety of sugar components compared with WPsP. FTIR analysis demonstrated characteristic polysaccharide absorption peaks in all six PSP components, with a predominance of acidic pyranose sugars. NMR analysis revealed the presence of pyranose sugars, including rhamnose and sugar aldehyde acids, in both DPsP-B and WPsP-A. DPsP-B primarily exhibited β-type glycosidic linkages, while WPsP-A predominantly displayed α-type glycosidic linkages, with a smaller fraction being β-type. These findings indicated differences in monosaccharide composition and structure between PSPs extracted using different methods. Overall, this study provided experimental evidence for future research on the structure-function relationship of PSPs.

Characterization of soluble dietary fiber from citrus peels (Citrus unshiu), and its antioxidant capacity and beneficial regulating effect on gut microbiota

This study aimed to evaluate the physicochemical, structural and functional properties of soluble dietary fiber extracted from citrus peels (Citrus unshiu) by ultrasound-assisted alkaline extraction. Unpurified soluble dietary fiber (CSDF) was compared with purified soluble dietary fiber (PSDF) in terms of composition, molecular weight, physicochemical properties, antioxidant activity, and intestinal regulatory capacity. Results showed that the molecular weight of soluble dietary fiber was >15 kDa, which showed good shear thinning characteristics and belonged to non-Newtonian fluid. The soluble dietary fiber showed good thermal stability under 200 °C. The contents of total sugar, arabinose and sulfate in PSDF were higher than those in CSDF. At the same concentration, PSDF showed stronger free radical scavenging ability. In fermentation model experiments, PSDF promoted the production of propionic acid and increased the abundance of Bacteroides. These findings suggested that soluble dietary fiber extracted by the ultrasound-assisted alkaline extraction has good antioxidant capacity and promotes intestinal health. It has broad development space in the field of functional food ingredients.

Effects of Abelmoschus manihot gum content, heating temperature and salt ions on the texture and rheology properties of konjac gum/Abelmoschus manihot gum composite gel

To improve the gelling property of konjac gum (KGM) and enhance the application value of Abelmoschus manihot (L.) medic gum (AMG), a novel type of gel was prepared using KGM and AMG in this study. The effects of AMG content, heating temperature and salt ions on the characteristics of KGM/AMG composite gels were studied by Fourier transform infrared spectroscopy (FTIR), zeta potential, texture analysis and dynamic rheological behavior analysis. The results indicated that the AMG content, heating temperature and salt ions could affect the gel strength of KGM/AMG composite gels. Hardness, springiness, resilience, G', G* and η* of KGM/AMG composite gels increased when AMG content increased from 0 to 2.0 %, but they decreased when AMG increased from 2.0 % to 3.5 %. High-temperature treatment significantly enhanced the texture and rheological properties of KGM/AMG composite gels. The addition of salt ions reduced the zeta potential absolute value and weakened the texture and rheological properties of KGM/AMG composite gels. Furthermore, the KGM/AMG composite gels could be classified as non-covalent gels. The non-covalent linkages included hydrogen bonding and electrostatic interactions. These findings would help understand the properties and formation mechanism of KGM/AMG composite gels and help improve the application value of KGM and AMG.

Chemical Evaluation of Liquidambar styraciflua L. Fruits Extracts and Their Potential as Anticancer Drugs

Liquidambar styraciflua L. is an aromatic species, popularly used in traditional Chinese medicine to treat diarrhea, dysentery, coughs, and skin sores. The present study was designed to investigate the chemical composition and biological potential of extracts obtained from the fruits of this plant. For the chemical evaluation, it was used mainly liquid and gas chromatography, plus NMR, and colorimetric methods. The aqueous extract (EA) originated two other fractions: an aqueous (P-EA) and an ethanolic (S-EA). The three extracts were composed of proteins, phenolic compounds, and carbohydrates in different proportions. The analyses showed that the polysaccharide extract (P-EA) contained pectic polysaccharides, such as acetylated and methyl esterified homogalacturonans together with arabinogalactan, while the fraction S-EA presented phenolic acids and terpenes such as gallic acid, protocathecuic acid, liquidambaric acid, combretastatin, and atractyloside A. EA, P-EA, and S-EA showed antioxidant activity, with IC50 values of 4.64 µg/mL, 16.45 µg/mL, and 3.67 µg/mL, respectively. The cytotoxicity followed the sequence S-EA > EA > P-EA, demonstrating that the toxic compounds were separated from the non-toxic ones by ethanol precipitation. While the fraction S-EA is very toxic to any cell line, the fraction P-EA is a promising candidate for studies against cancer due to its high toxicity to tumoral cells and low toxicity to normal cells.

Isolation of a New Polysaccharide from Dandelion Leaves and Evaluation of Its Antioxidant, Antibacterial, and Anticancer Activities

Dandelion, in China, has a long history as a medicinal and edible plant, and possesses high nutritional and medical value. The present study aimed to isolate a new polysaccharide (DLP-3) from dandelion leaves and to evaluate its antioxidant, antibacterial, and anticancer activities. The structure of DLP-3 was analyzed using HPLC, FT-IR, SEM, GC-MS, and NMR spectroscopy. DLP-3 mainly consisted of Man, Rha, GlcA, Glc, Gal, and Ara with molar ratios of 2.32, 0.87, 1.21, 3.84, 1.00, and 1.05, respectively, with a molecular weight of 43.2 kDa. The main linkages of DLP-3 contained (1→4)-α-d-Glc, (1→4,6)-α-d-Glc, (1→6)-α-d-Gal, (1→2)-α-d-Man, (1→4)-α-d-Man, β-l-Ara-(1→, and α-l-Rha-(1→. DLP-3 exhibited a smooth surface, purely flake-like structure, and a triple helix conformation. Moreover, DLP-3 presented obvious antioxidant and antibacterial activities in a concentration-dependent manner. DLP-3 showed significant anticancer activities by inhibiting tumor cell proliferation. These findings provide a theoretical basis for the application of DLP-3 as a natural functional active substance in functional foods.

Biological characteristics, bioactive compounds, and antioxidant activities of off-season mulberry fruit

To understand the yield and quality of off-season mulberry fruits, which are cultivated in open fields from autumn, the biological characteristics, bioactive compounds, and antioxidant activities of them were analyzed. Compared with mulberry fruits in normal season, the fruit length, fruit diameter, single fruit weight, fruit yield per meter strip, and the fruits yield per 667 m² are significantly lower. The moisture content and juice yield of off-season mulberry fruits are lower than the mulberry fruits in normal season; the pH and soluble solids are higher. The contents of mass fraction of crude protein, total sugar, reducing sugar, total acids, total anthocyanins, and total flavonoids decreased significantly in all batches of off-season mulberry fruits compared with those of normal season. Of off-season mulberry fruits, the contents of glucose, fructose and sucrose, expression, anthocyanin biosynthesis genes, and antioxidant capacity are significantly lower than those in normal season.

Microwave-Assisted Deep Eutectic Solvent Extraction, Structural Characteristics, and Biological Functions of Polysaccharides from Sweet Tea (Lithocarpus litseifolius) Leaves

The leaf of sweet tea (Lithocarpus litseifolius) is widely used as an edible and medicinal plant in China, which is rich in bioactive polysaccharides. In order to explore and promote the application of sweet tea polysaccharides in the functional food industry, the microwave-assisted deep eutectic solvent extraction (MDAE) of polysaccharides from sweet tea leaves was optimized, and the structural properties and biological functions of sweet tea polysaccharides prepared by MDAE (P-DM) were investigated and compared with that of hot water extraction (P-W). The maximum yield (4.16% ± 0.09%, w/w) of P-DM was obtained under the optimal extraction conditions (extraction time of 11.0 min, extraction power of 576.0 W, water content in deep eutectic solvent of 21.0%, and liquid–solid ratio of 29.0 mL/g). Additionally, P-DM and P-W possessed similar constituent monosaccharides and glycosidic bonds, and the homogalacturonan (HG) and arabinogalactan (AG) might exist in both P-DM and P-W. Notably, the lower molecular weight, higher content of total uronic acids, and higher content of conjugated polyphenols were observed in P-DW compared to P-W, which might contribute to its much stronger in vitro antioxidant, anti-diabetic, antiglycation, and prebiotic effects. Besides, both P-DW and P-W exhibited remarkable in vitro immunostimulatory effects. The findings from the present study indicate that the MDAE has good potential to be used for efficient extraction of bioactive polysaccharides from sweet tea leaves and P-DM can be developed as functional food ingredients in the food industry.

Comparative Characterization and Immunomodulatory Activities of Polysaccharides Extracted from the Radix of Platycodon grandiflorum with Different Extraction Methods

Platycodon grandiflorum is an edible and medicinal plant, and polysaccharides are one of its important components. To further improve the utilization rate of P. grandiflorum, we investigated the effects of four different extraction methods, including hot water, ultrasonic-assisted, acid-assisted, and alkali-assisted extractions, on the polysaccharides, which were named PG-H, PG-U, PG-C, and PG-A. The findings indicated that the extraction method had a significant impact on the yield, characteristics, and immunoregulatory activity. We observed that the yields decreased in the following order: PG-H, PG-U, PG-C, and PG-A. Galacturonic acid, glucose, galactose, and arabinose were the most prevalent monosaccharides in the four PGs. However, their proportions varied. In addition, the difference between the content of glucose and galacturonic acid was more significant. PG-U had the highest glucose content, whereas PG-C had the lowest. Galacturonic acid content was highest in PG-A, while the lowest in PG-U. The molecular weight decreased in the order of PG-U, PG-H, PG-C, and PG-A; the particle size was in the order of PG-U, PG-A, PG-H, and PG-C. Moreover, the extraction method had a great impact on immunoregulatory activity. The ability to stimulate the immune function of macrophages was as follows: PG-A > PG-C > PG-U > PG-H. The results indicated that PGs, with lower molecular weights and higher GalA content, exhibited better immune-stimulating activity. And more important the AAE method was a good way to extract polysaccharides from Platycodon grandiflorum for use as a functional product and immunological adjuvant.

A Comparison Study on Polysaccharides Extracted from Atractylodes chinensis (DC.) Koidz. Using Different Methods: Structural Characterization and Anti-SGC-7901 Effect of Combination with Apatinib

For hundreds of years, Atractylodes chinensis (DC.) Koidz. (AK) has been widely used as a treatment for spleen and stomach diseases in China. The AK polysaccharides (AKPs) have been thought to be the important bioactive components. In this stud, the impacts of different extraction methods were analyzed. The differences between AKPs extracted by hot water extraction (HWE), AKPs extracted by ultrasonic extraction (UAE), and AKPs extracted by enzyme extraction (EAE) were compared in terms of yield, total carbohydrate content, molecular weight distribution, monosaccharide composition, and synergistic activity of the AKPs with apatinib were determined. The results indicated that the yield of the polysaccharide obtained from HWE was higher than that of UAE and EAE. However, activity assays indicated that UAE-AKPs and HWE-AKPs enhanced apoptosis of human gastric cancer cells (SGC-7901) treated with apatinib and UAE-AKPs showed the strongest synergistic activities. This is also in agreement with the fact that UAE-AKPs have a smaller molecular weight, β-configuration, and higher galactose content. These findings suggested that UAE is an efficient and environmentally friendly method for producing new polysaccharides from Atractylodes chinensis (DC.) Koidz. for the development of natural synergist and for the treatment of gastric cancer.

Impact of thermally induced wall breakage on the structural properties of water-soluble polysaccharides in chickpeas

The present work aimed to elucidate the influence of wall breakage induced by thermal processing on the molecular, structural, and antioxidant activities of water-soluble polysaccharides in chickpeas. Different extents of cell wall disruption were observed by fluorescence microscopy in chickpea cotyledons. Moreover, a decreasing fluorescence intensity of cell wall fragments was observed in the flour residues upon heat fluidization, autoclaving, and microwave heating, and the polysaccharide extraction rates were increased by 31.47%, 25.52%, and 9.79%, respectively. Furthermore, WPUCP, WPHCP, WPMCP, and WPACP (water-soluble polysaccharides from unprocessed, heat fluidized, microwaved, and autoclaved chickpeas, respectively) were RG-I (rhamnogalacturonan-I)-enriched pectic polysaccharides composed of galactose, arabinose, galacturonic acid, and rhamnose. After chickpea thermal processing, the degrees of branching decreased to 2.87, 3.79, and 2.53 in WPHCP, WPMCP, and WPACP, respectively, and the molecular weights were reduced by 46.46%, 24.83%, and 59.91%, respectively. Structural analysis showed that the semicrystalline regions of WPHCP, WPMCP, and WPACP were slightly damaged without changing the functional groups, but their thermal stability decreased. Interestingly, WPACP formed an ordered conformation (microporous network structure) through the formation of hydrogen bonds. Moreover, the antioxidant activities of WPHCP, WPMCP, and WPACP were enhanced, and the strongest radical scavenging activity was observed for WPHCP.

Structural Elucidation, Modification, and Structure-Activity Relationship of Polysaccharides in Chinese Herbs: A Review

Chinese herbal polysaccharides (CHPs) are natural polymers composed of monosaccharides, which are widely found in Chinese herbs and work as one of the important active ingredients. Its biological activity is attributed to its complex chemical structure with diverse spatial conformations. However, the structural elucidation is the foundation but a bottleneck problem because the majority of CHPs are heteropolysaccharides with more complex structures. Similarly, the studies on the relationship between structure and function of CHPs are even more scarce. Therefore, this review summarizes the structure-activity relationship of CHPs. Meanwhile, we reviewed the structural elucidation strategies and some new progress especially in the advanced structural analysis methods. The characteristics and applicable scopes of various methods are compared to provide reference for selecting the most efficient method and developing new hyphenated techniques. Additionally, the principle structural modification methods of CHPs and their effects on activity are summarized. The shortcomings, potential breakthroughs, and developing directions of the study of CHPs are discussed. We hope to provide a reference for further research and promote the application of CHPs.

Phytochemicals, Pharmacological Effects and Molecular Mechanisms of Mulberry

There are numerous varieties of mulberry, and each has high medicinal value and is regarded as a promising source of traditional medicines and functional foods. Nevertheless, the nutrients and uses of mulberry differ from species (Morus alba L., Morus nigra L. and Morus rubra L.). Phenolic compounds are prominent among the biologically active ingredients in mulberry, especially flavonoids, anthocyanins and phenolic acids. Epidemiologic studies suggest that mulberry contains a rich, effective chemical composition and a wide range of biological activity, such as antioxidant, anti-inflammatory, anti-tumor and so on. However, compared with other berries, there has been a lack of systematic research on mulberry, and this hinders its further expansion as a functional fruit. The main purpose of this review is to provide the latest data regarding the effective chemical constituents and pharmacological effects of mulberry to support its further therapeutic potential and health functions.

Research on Extraction, Structure Characterization and Immunostimulatory Activity of Cell Wall Polysaccharides from Sparassis latifolia

The cell wall polysaccharides were extracted from Sparassis latifolia fruit bodies by acid-alkali and superfine-grinding assisted methods, and the chemical characterization and in vitro immunity activities of these polysaccharide fractions were studied and compared. Results showed that superfine-grinding assisted extraction exhibited the highest yield of polysaccharides (SP, 20.80%) and low β-glucan content (19.35%) compared with alkaline extracts. The results revealed that the 20% ethanol precipitated fraction (20E) from SP was mainly composed of β-(1→3)-glucan and α-(1→4)-glucan. With the increase of ethanol precipitation, the fractions (30E, 40E, 50E) were identified as α-(1→4)-glucan with different molecular weights and conformations. Cell wall polysaccharides extracted through NaOH (NSP) and KOH (KSP) extraction had similar yields with 8.90% and 8.83%, respectively. Structural analysis indicated that the purified fraction from KSP (KSP-30E) was a β-(1→3)-glucan backbone branched with β-(1→6)-Glcp, while the purified fraction from NSP (NSP-30E) mainly contained β-(1→3)-glucan with a small number of α-linked-Glcp. The two fractions both exhibited rigid chain conformation in aqueous solutions. All polysaccharide fractions exerted the activity of activating Dectin-1 receptor in vitro, and the KSP-30E mainly identified as β-(1→3)-glucan with the terminal group via 1→6-linkage attached at every third residue exhibited a stronger enhancing effect than other fractions. Results suggested that KOH extraction could be efficient for the preparation of bioactive β-(1→3, 1→6)-glucan as a food ingredient.

Isolation, Chemical Characterization and Antioxidant Activity of Pectic Polysaccharides of Fireweed (Epilobium angustifolium L.)

The aim of this study was to isolate pectins with antioxidant activity from the leaves of Epilobium angustifolium L. Two pectins, EA-4.0 and EA-0.8, with galacturonic acid contents of 88 and 91% were isolated from the leaves of E. angustifolium L. by the treatment of plant raw materials with aqueous hydrochloric acid at pH 4.0 and 0.8, respectively. EA-4.0 and EA-0.8 were found to scavenge the DPPH radical in a concentration-dependent manner at 17–133 μg/mL, whereas commercial apple pectin scavenged at 0.5–2 mg/mL. The antioxidant activity of EA-4.0 was the highest and exceeded the activity of EA-0.8 and a commercial apple pectin by 2 and 39 times (IC₅₀—0.050, 0.109 and 1.961 mg/mL), respectively. Pectins EA-4.0 and EA-0.8 were found to possess superoxide radical scavenging activity, with IC₅₀s equal to 0.27 and 0.97 mg/mL, respectively. Correlation analysis of the composition and activity of 32 polysaccharide fractions obtained by enzyme hydrolysis and anionic exchange chromatography revealed that the antioxidant capacity of fireweed pectins is mainly due to phenolics and is partially associated with xylogalacturonan chains. The data obtained demonstrate that pectic polysaccharides appeared to be bioactive components of fireweed leaves with high antioxidant activity, which depend on pH at their extraction.

Characterization, Antioxidant and Antitumor Activities of Oligosaccharides Isolated from Evodia lepta (Spreng) Merr. by Different Extraction Methods

Evodia lepta (E. lepta) is a traditional Chinese herbal medicine with various biological activities. One of the active components of this widely used medicinal plant is believed to be an oligosaccharide. The extraction yields, structural characteristics, antioxidant, and antitumor activities of four oligosaccharide extracts obtained by hot water extraction (HEO), ultrasound-assisted extraction (UEO), enzyme-assisted (EEO), and microwave-assisted extraction (MEO) were investigated. Matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS), X-ray diffraction (XRD), and Scanning electron microscopy (SEM) results indicated that the extraction methods had a difference on the molecular mass distribution, structure, and morphology of the EOs. In addition, HEO and MEO showed strong antioxidant activities, which might be related to their uronic acid and protein contents. More interestingly, MEO was more active toward MDA-MB-231 cells compared to other cells, and cell growth inhibition was proposed to occur through apoptosis. Overall, microwave-assisted extraction is a promising technique for the extraction of high quality EO.

Pharmacological Activities for Morus alba L., Focusing on the Immunostimulatory Property from the Fruit Aqueous Extract

Depending on the extraction method, numerous compounds that have specific pharmacological effects can be obtained from M. alba L. There is a growing scientific interest in health problems related to aging. Efforts to develop safe immune-enhancing pharmaceuticals are increasing. This review aims to summarize and critically discuss the immunity enhancement effects and pharmaceutical efficacy of M. alba L. extracts. The scientific database search was conducted using Google Scholar, Web of Science, and PubMed until May 2021. Additional articles were identified and obtained from references in the retrieved articles. Ethanol or methanol extraction of various parts of M. alba L. identified a large amount of phenols and flavonoids, which are effective for immunosuppression, antioxidants, and cardiovascular diseases, and are antibacterial, and anticancer. Water extraction of M. alba L. enhanced the innate immune response based on immune cell activation. A polysaccharide and an alkaloid related to increased macrophage activity were isolated from M. alba L. fruit extracts. M. alba L. fruit water extracts primarily induced the production of pro-inflammatory substances, in model organisms, via TLR4 in immune cells. Water extracts have been shown to be effective in pathogen defense and tumor suppression by enhancing macrophage activity. Based on our literature review on the bioactivity of M. alba L. fruit extracts, particularly in relation to their immunity enhancement activity, we anticipate that M. alba-derived pharmaceuticals will have excellent potential in future medical research.