Physicochemical Properties, Antioxidant and Antidiabetic Activities of Polysaccharides from Quinoa (Chenopodium quinoa Willd.) Seeds

Effects of aging on the fine structure, chain conformation, and morphology of Chenpi polysaccharides

The aging process endows Chenpi (Pericarpium Citri Reticulatae) with unique value and efficacy. This study investigated the dynamic changes in the fine structure, chain conformation, and morphology of water-soluble polysaccharides from Chenpi over time. In the initial storage period of Chenpi (1 year), Chenpi polysaccharides (CP) exhibited a triple-helical structure, with chains entangled and aggregated into rough spherical conformations. Galacturonic acid (GalA, 47.78 mol%) was the predominant monosaccharide. As aging progressed, the homogalacturonan (HG) regions gradually degraded, leading to decreases in molecular sizes (particle size, Mw, Mn, and Rg), a reduction in the degree of esterification, and a weakening of the semicrystalline structure. Consequently, arabinose (Ara) emerged as the main monosaccharide (41.38 mol%). Neutral sugars continuously enriched the rhamnogalacturonan (RG-I) side chains, forming highly branched single molecules that curled into spherical shapes. By 15 years, CP were fully degraded, adopting a compact molecular conformation with the triple-helix structure disappearing and sizes uniformly below 20 nm. However, AFM results indicated aggregation phenomena in 15-year CP. Additionally, CP viscosity decreased while thermal stability improved, reflecting the natural structural transformation of CP. This study provides scientific evidence supporting the application of Chenpi in the food and pharmaceutical industries.

Structure-activity relationship of synthesized glucans from Ganoderma lucidum with in vitro hypoglycemic activity

The synthetic polysaccharides, which have precise structure, can be used to design new drugs by comparing structure-activity relationships (SAR). Improved protein stability may be due to the interaction between the polysaccharides and protein, which includes covalent and noncovalent interactions. It is critical to investigate the SAR of polysaccharides with a precise structure from the perspective of protein stability. Glucans-insulin interaction may be a useful stratagy to solve this problem. This study reports the SAR of the synthesized glucan GLSWA-1 and its substructures 2-4 on insulin secretion and discusses its mechanism. The results showed that although GLSWA-1 and its substructures 2-4 bind insulin to varying degrees, compound 2 improves insulin secretion in a dose-dependent manner. Further research found that compound 2 maintains the thermal stability of insulin better than GLSWA-1 through stronger hydrogen bonding, and molecular dynamics simulations demonstrated that compound 2 can form a "groove-binding model" with insulin. This study considerably improves the research on the SAR of glucan based on insulin thermostability and indicates that compound 2, its linear structure, appropriate chain flexibility ((1 → 6)-glucoside bonds), low molecular weight, and smaller steric hindrance is a potential hypoglycemic agent.

Quinoa Polysaccharides: Extraction, Purification, Structure, Functional Properties, and Applications in Food Science and Health

Quinoa polysaccharides have attracted significant research interest in recent years due to their diverse biological activities, including antiviral, anti-inflammatory, antioxidant, and immunoregulatory properties. These attributes align with the growing global demand for natural, functional food ingredients, positioning quinoa polysaccharides as a valuable resource in food science and technology. This review presents an overview of the various bioactivities of quinoa polysaccharides, critically evaluates the methods used for their extraction and purification, describes their structural characteristics, and discusses their practical applications across multiple areas within the food industry, including food additives, meat products, health foods, and innovative food packaging. This study examines the relationship between the preparation methods and the structural characteristics of quinoa polysaccharides, as well as their versatile applications in the food industry, such as improving product quality and shelf life, enhancing nutritional value and antioxidant activity, and providing health benefits in functional foods. This review also emphasizes the need for further research on the emulsification and gelation properties of quinoa polysaccharides and highlights their significant market potential, driven by their diverse functional properties. From our perspective, quinoa polysaccharides, with their wide range of functional and health benefits, hold a promising future in the food and health industries, driven by technological advancements and consumer demands.

A review of in vitro antioxidant and antidiabetic polysaccharides: Extraction methods, physicochemical and structure-activity relationships

Nowadays, various plant polysaccharides have been successfully extracted which exhibited strong biological activities and might be useful for diabetes management. However, the effect of extraction methods, physicochemical and the structural-activity relationships of polysaccharides to exhibit antioxidants and antidiabetics were inadequate to explain their mechanism in action. The uses of advance extraction methods might be preferred to obtain higher antioxidants and antidiabetic activities of polysaccharides compared to conventional methods, but the determination of optimal extraction conditions might be crucial to preserve their structure and biological functions. Other than that, the physicochemical and structural properties of polysaccharides were closely related to their biological activities such as antioxidant and antidiabetic activities. Therefore, this review addressed the research gap of the influence of extraction methods, physicochemical and structural relationships of polysaccharides to biological activities, pointing out the challenges and limitations as well as future prospects to the current findings.

Nutrition, health benefits, and processing of sand rice (Agriophyllum squarrosum): Comparisons with quinoa and buckwheat

The dual pressures of climate change and population growth have made the development of new grains a necessity. Agriophyllum squarrosum (sand rice) has high adaptability to harsh environments and does not occupy agricultural land. It is widely cultivated and consumed in Central Asia. Sand rice, together with quinoa and buckwheat, belongs to the same pseudocereals group with rich nutritional value and gluten-free properties; however, its nutritional composition and health benefits differ from those of quinoa and buckwheat. Sand rice seeds are a rich source of nutrients and bioactive compounds, including proteins, amino acids, unsaturated fatty acids, and crude fiber, which are similar to those in buckwheat and quinoa; however, their starch content is relatively low. Sand rice seeds also possess phenolic acids and flavonoids, which exhibit antioxidant, anticancer, anti-diabetes, and anti-inflammatory properties. Furthermore, sand rice extracts are considered suitable for treating some chronic diseases. Overall, sand rice is considered a good plant-based food that can be used to develop various functional foods and beverages or mixed with other grains in different recipes. However, advancements in the processing technology of sand rice-based foods are required to fully exploit the potential of sand rice in the food industry to improve human health. This review analyzes the current understanding of the nutritional content of sand rice by comparing it with that of quinoa and buckwheat. Furthermore, its potential medicinal activity and feasibility as a functional ingredient to improve food quality is discussed.

Ultrasound-Assisted Enzyme Extraction, Physicochemical Properties and Antioxidant Activity of Polysaccharides from Cordyceps militaris Solid Medium

Cordyceps militaris solid medium polysaccharides (CMMPs) were extracted using an ultrasound-assisted enzyme method, and the process conditions were optimized via response surface methodology (RSM). The CMMPs were separated into four components named CMMP-1, CMMP-2, CMMP-3 and CMMP-4 using ethanol fractional precipitation, and their monosaccharide composition and structural properties were analyzed by molecular weight analysis, Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), Congo red test, ultraviolet-visible spectroscopy (UV-vis), atomic force microscopy (AFM), and thermogravimetric analysis (TGA). RSM could predict the yield of the CMMP (R2 = 0.9928), and the polysaccharide yield was 15.43% under the selected conditions of 3.1% cellulase enzyme addition, a liquid-solid ratio of 42:1, an extraction temperature of 61 °C, and an extraction time of 60 min. Glucose and galactose were the main constituents of the four fractional precipitated polysaccharides. Furthermore, four components exhibited antioxidant activity, and CMMP-1 demonstrated stronger antioxidant activity in vitro. This study demonstrates the possibility of developing a natural antioxidant food from Cordyceps militaris solid medium.

Simulated Gastrointestinal Digestion and Fecal Fermentation Characteristics of Exopolysaccharides Synthesized by Schleiferilactobacillus harbinensis Z171

Exopolysaccharides (EPSs) produced by Lactobacillus have important physiological activities and are commonly used as novel prebiotics. A strain of Lactobacillus with high EPS yield was identified as Schleiferilactobacillus harbinensis (S. harbinensis Z171), which was isolated from Chinese sauerkraut. The objective of this study was to investigate the in vitro simulated digestion and fecal fermentation behavior of the purified exopolysaccharide fraction F-EPS1A from S. harbinensis Z171 and its influence on the human intestinal flora composition. The in vitro digestion results showed that the primary structural characteristics of F-EPS1A, such as morphology, molecular weight, and monosaccharide composition remained stable after saliva and gastrointestinal digestion. Compared with the blank group, the fermentation of F-SPS1A by fecal microbiota decreased the diversity of the bacterial communities, significantly promoted the relative abundance of Bifidobacterium and Faecalibacterium, and decreased the relative abundance of Lachnospiraceae_Clostridium, Fusobacterium, and Oscillospira. Reverse transcription polymerase chain reaction (RT-PCR) analysis also showed that the population of Bifidobacterium markedly increased. Furthermore, the total short-chain fatty acid levels increased significantly, especially for butyric acid. Gas chromatography-mass spectrometry (GC-MS) results showed that F-EPS1A could be fermented by the human gut microbiota to synthesize organic acids and derivative metabolites that are beneficial to gut health. Therefore, these findings suggest that F-EPS1A could be exploited as a potential prebiotic.

Advances in Eucommia ulmoides polysaccharides: extraction, purification, structure, bioactivities and applications

Eucommia ulmoides (EU) is a precious tree species native to China originating during the ice age. This species has important economic value and comprehensive development potential, particularly in medicinal applications. The medicinal parts of EU are its bark (Eucommiae cortex) and leaves (Eucommiae folium) which have been successively used as a traditional Chinese medicine to treat diseases since the first century BC. During the last 2 decades, as natural polysaccharides have become of increasing interest in pharmacology, biomedicine, cosmetic and food applications, more and more scholars have begun to study polysaccharides derived from EU as well. EU polysaccharides have been found to have a variety of biological functions both in vivo and in vitro, including immunomodulatory, antioxidant, anti-inflammatory, anticomplementary, antifatigue, and hepatoprotective activities. This review aims to summarize these recent advances in extraction, purification, structural characteristics, pharmacological activities and applications in different fields of EU bark and leaf polysaccharides. It was found that both Eucommiae folium polysaccharides and Eucommiae cortex polysaccharides were suitable for medicinal use. Eucommiae folium may potentially be used to substitute for Eucommiae cortex in terms of immunomodulation and antioxidant activities. This study serves as a valuable reference for improving the comprehensive utilization of EU polysaccharides and further promoting the application of EU polysaccharides.

Harnessing the Potential of Quinoa: Nutritional Profiling, Bioactive Components, and Implications for Health Promotion

Quinoa, a globally cultivated "golden grain" belonging to Chenopodium in the Amaranthaceae family, is recognized for being gluten-free, with a balanced amino acid profile and multiple bioactive components, including peptides, polysaccharides, polyphenols, and saponins. The bioactive compounds extracted from quinoa offer multifaceted health benefits, including antioxidative, anti-inflammatory, antimicrobial, cardiovascular disease (CVD) improvement, gut microbiota regulation, and anti-cancer effects. This review aims to intricately outline quinoa's nutritional value, functional components, and physiological benefits. Importantly, we comprehensively provide conclusions on the effects and mechanisms of these quinoa-derived bioactive components on multiple cancer types, revealing the potential of quinoa seeds as promising and effective anti-cancer agents. Furthermore, the health-promoting role of quinoa in modulating gut microbiota, maintaining gut homeostasis, and protecting intestinal integrity was specifically emphasized. Finally, we provided a forward-looking description of the opportunities and challenges for the future exploration of quinoa. However, in-depth studies of molecular targets and clinical trials are warranted to fully understand the bioavailability and therapeutic application of quinoa-derived compounds, especially in cancer treatment and gut microbiota regulation. This review sheds light on the prospect of developing dietary quinoa into functional foods or drugs to prevent and manage human diseases.

Bioactive properties and gut microbiota modulation by date seed polysaccharides extracted using ultrasound-assisted deep eutectic solvent

Polysaccharides are abundant macromolecules. The study extracted date seed polysaccharides (UPS) using ultrasound-assisted deep eutectic solvent extraction to valorize date seeds. UPS were subjected to comprehensive characterization and evaluation of their bioactivity, prebiotic properties, and their potential to modulate the gut microbiome. Characterization revealed UPS's heteropolysaccharide composition with galactose, mannose, fructose, glucose, and galacturonic acid respectively in 66.1, 13.3, 9.9, 5.4, and 5.1%. UPS showed a concentration-dependent increase of radical scavenging and antioxidant activities, evidenced by FRAP, TAC, and RP assays. They also displayed antimicrobial efficacy against E. coli O157:H7, S. typhimurium, S. aureus, and L. monocytogenes. Rheological analysis showed UPS's elastic-dominant nature with thixotropic tendencies. UPS inhibited α-glycosidase, α-amylase, and ACE up to 86%, and reduced Caco-2 and MCF-7 cell viability by 70% and 46%, respectively. UPS favored beneficial gut microbiota growth, releasing significant SCFAs during fecal fermentation.

Effect of Moringa oleifera leaf polysaccharide on the composition of intestinal microbiota in mice with dextran sulfate sodium-induced ulcerative colitis

Moringa oleifera (M. oleifera) is a natural plant that has excellent nutritional and medicinal potential. M. oleifera leaves (MOL) contain several bioactive compounds. The aim of this study was to evaluate the potential effect of MOL polysaccharide (MOLP) on intestinal flora in dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) mice. DSS-induced colitis was deemed to be a well-characterized experimental colitis model for investigating the protective effect of drugs on UC. In this study, we stimulated the experimental mice with DSS 4% for 7 days and prepared the high dose of MOLP (MOLP-H) in order to evaluate its effect on intestinal flora in DSS-induced UC mice, comparing three experimental groups, including the control, DSS model, and DSS + MOLP-H (100 mg/kg/day). At the end of the experiment, feces were collected, and the changes in intestinal flora in DSS-induced mice were analyzed based on 16S rDNA high throughput sequencing technology. The results showed that the Shannon, Simpson, and observed species indices of abundance decreased in the DSS group compared with the control group. However, the indices mentioned above were increased in the MOLP-H group. According to beta diversity analysis, the DSS group showed low bacterial diversity and the distance between the control and MOLP-H groups, respectively. In addition, compared with the control group, the relative abundance of Firmicutes in the DSS group decreased and the abundance of Helicobacter increased, while MOLP-H treatment improves intestinal health by enhancing the number of beneficial organisms, including Firmicutes, while reducing the number of pathogenic organisms, such as Helicobacter. In conclusion, these findings suggest that MOLP-H may be a viable prebiotic with health-promoting properties.

Exploratory review on the evidence of Andean crops with hypoglycemic effect and their bioactive components

Diabetes is a chronic disease that affects several people around the world. Some domesticated crops in South America have been reported to be a promising source of bioactive compounds with possible hypoglycemic effects. In this review we aimed to explore and synthesize the existing evidence in the scientific literature on the hypoglycemic effect of Andean crops and their bioactive components. We included different types of primary studies from three databases (Scopus, Pubmed and Web of Science) during June 2023, without restrictions, by means of controlled and uncontrolled language, according to the PICO strategy. We found 30 studies conducted between 2005 and 2022 that reported a hypoglycemic effect, through enzymatic inhibition in in vitro studies and significant glucose reduction in preclinical studies and clinical trials. This effect was attributed to different bioactive components that were identified with independent mechanisms related to glucose reduction and enzymatic inhibition. The most commonly used cultures were Smallanthus sonchifolius (9/30), Lupinus mutabilis (5/30) and Solanum tuberosum (4/30). The hypoglycemic effect was assigned to bioactive components such as polyphenols, flavonoids, phenolic acid subclasses, fructans, alkaloids, hydrolysates, anthocyanins and dietary fiber. Despite encouraging results from different types of studies, further research on their mechanisms of action, their efficacy compared to conventional treatments and their long-term safety is required for these to be considered safe and effective treatments.

Comparison of soluble dietary fibers from various quinoa microgreens: Structural characteristics and bioactive properties

Quinoa (Chenopodium quinoa Willd.) microgreens are widely consumed as healthy vegetables around the world. Although soluble dietary fibers exist as the major bioactive macromolecules in quinoa microgreens, their structural characteristics and bioactive properties are still unclear. Therefore, the structural characteristics and bioactive properties of soluble dietary fibers from various quinoa microgreens (QMSDFs) were investigated in this study. The yields of QMSDFs ranged from 38.82 to 52.31 mg/g. Indeed, all QMSDFs were predominantly consisted of complex pectic-polysaccharides, e.g., homogalacturonan (HG) and rhamnogalacturonan I (RG I) pectic domains, with the molecular weights ranged from 2.405 × 104 to 5.538 × 104 Da. In addition, the proportions between RG I and HG pectic domains in all QMSDFs were estimated in the range of 1: 2.34-1: 4.73 (ratio of galacturonic acid/rhamnose). Furthermore, all QMSDFs exhibited marked in vitro antioxidant, antiglycation, prebiotic, and immunoregulatory effects, which may be partially correlated to their low molecular weights and low esterification degrees. These findings are helpful for revealing the structural and biological properties of QMSDFs, which can offer some new insights into further development of quinoa microgreens and related QMSDFs as value-added healthy products.

Response surface methodology based development of an optimized polyherbal formulation and evaluation of its anti-diabetic and anti-obesity potential in high-fat diet-induced obese mice

Background and aim

The seeds of Nelumbo nucifera, Chenopodium quinoa and Salvia hispanica are known as super foods due to their various therapeutic properties. The present study aimed to develop an optimized polyherbal formulation from edible seeds aqueous extract and to evaluate its anti-diabetic and lipase inhibitory effect on diet-induced obese diabetic mice.

Experimental procedure

Response surface methodology based various formulations were evaluated for their potent anti-diabetic, lipase-inhibitory and antioxidant activities. Acute toxicity of the best optimized formulation was conducted. The mice were fed a high fat diet for 10 weeks resulting in hyperglycemia and obesity. Oral tolerance tests (sucrose, starch and lipid) of the formulation were performed. The mice were supplemented with different doses (125, 250 and 500 mg/kg) of the formulation for 6 weeks. The body weight and blood glucose level were monitored on a weekly basis. Finally, histological alterations and lipid profiles were analysed.

Results and conclusion

The formulation containing equal concentration (1.5 mg/ml) of each seed extract showed maximum bioactivities. The formulation was found to be safe during toxicity assay. The tolerance tests supported the anti-diabetic and anti-obesity effect. Higher dose (500 mg/kg) of the formulation significantly (p < 0.01) lowered elevated fasting blood glucose, lipid indices and ameliorated the histological alterations in liver, kidney and pancreas caused by high fat diet. We demonstrated for the first time that the developed aqueous extract optimized formulation possess anti-diabetic and anti-obesity potential and thus could be used as adjuvant therapy for holistic management of type 2 diabetes mellitus.

Immunomodulatory Activity and Its Mechanisms of Two Polysaccharides from Poria cocos

Polyporaceae is an important fungal family that has been a source of natural products with a range of pharmaceutical activities in China. In our previous study, two polysaccharides, PCWPW and PCWPS, with significant antioxidant and antidepressant activity were obtained from Poria cocos. In this study, we evaluated their potential molecular mechanisms in the immunomodulation of macrophages. PCWPW and PCWPS were characterized by GC-MS analysis to contain 1,3-linked Glcp. ELISA assays results demonstrated that the secretion of TNF-α was significantly enhanced by PCWPW/PCWPS. RNA-seq data demonstrated that PCWPS treatment modulated the expression of immune-related genes in macrophages, which was further confirmed by RT-qPCR assays. The activation of TNF-α secretion was found to be mannose receptor (MR) dependent and suppressed by MR inhibitor pretreatment. Moreover, the amount of TNF-α cytokine secretion in PCWPW/PCWPS-induced RAW264.7 cells was decreased when pretreated with NF-κB or MAPK signaling pathway inhibitors. Collectively, our results suggested that PCWPW and PCWPS possessed immunomodulatory activity that regulates TNF-α expression through the NF-κB/MAPK signaling pathway by binding to mannose receptors. Therefore, PCWPW and PCWPS isolated from Poria cocos have potential as drug candidates for immune-related disease treatment.

Phenolic Constituents from Black Quinoa Alleviate Insulin Resistance in HepG2 Cells via Regulating IRS1/PI3K/Akt/GLUTs Signaling Pathways

Quinoa is a nutrient-rich pseudocereal with a lower glycemic index and glycemic load. However, its therapeutic potency and underlying mechanism against insulin resistance (IR) have not been fully elucidated. In this work, network pharmacology was applied to screen IR targets and their related pathways. The efficacy and mechanism of black quinoa polyphenols (BQP) on IR improvement were evaluated and uncovered based on the IR model in vitro combined with molecular docking. Ten phenolic constituents of BQP were detected, and the network pharmacology results show that PI3K/Akt pathways are the main pathways in BQP against IR. The in vitro assay proved that BQP increases the glucose consumption and glycogen synthesis via upregulating insulin receptor substrate 1 (IRS1)/PI3K/Akt/glucose transporters (GLUTs) signaling pathways to alleviate IR. Rutin, resveratrol, and catechin show lower binding energy docking with IRS1, PI3K, Akt, and GLUT4 proteins, indicating better interactions. It might be an effective constituent against IR. Hence, BQP could become a potential functional food source for blood glucose management among insulin-resistant people.

Nutrient composition, functional activity and industrial applications of quinoa (Chenopodium quinoa Willd.)

Quinoa is one of the gluten-free crops that has attracted considerable interest. Quinoa contains functional ingredients such as bioactive peptides, polysaccharides, saponins, polyphenols, flavonoids and other compounds. It is very important to determine efficient methods to identify such functional ingredients, and to explain their possible health benefits in humans. In this review, the chemical structure and biological activity mechanisms of quinoa nutrient composition have been elaborated. In addition, the development of quinoa-based functional foods and feed is emerging, providing a reference for the development of functional products with quinoa as an ingredient that are beneficial to health. The active ingredients in quinoa have different health effects including antioxidant, antidiabetic, antihypertensive, anti-inflammatory, and anti-obesity activities. Further exploration is also needed to improve the application of quinoa within the functional food industry, and in the areas of feed, medicine and cosmetics.

Polysaccharides and lipoproteins as reactants for the synthesis of pharmaceutically important scaffolds: A review

The growing number of diseases in the past decade has once again highlighted the need for extensive research on the development of novel drugs. There has been a major expansion in the number of people suffering from malignant diseases and types of life-threatening microbial infections. The high mortality rates caused by such infections, their associated toxicity, and a growing number of microbes with acquired resistance necessitate the need to further explore and develop the synthesis of pharmaceutically important scaffolds. Chemical entities derived from biological macromolecules like carbohydrates and lipids have been explored and observed to be effective agents in the treatment of microbial infections and diseases. These biological macromolecules offer a variety of chemical properties that have been exploited for the synthesis of pharmaceutically relevant scaffolds. All biological macromolecules are long chains of similar atomic groups which are connected by covalent bonds. By altering the attached groups, the physical and chemical properties can be altered and molded as per the clinical applications and needs, this ring them potential candidates for drug synthesis. The present review establishes the role and significance of biological macromolecules by articulating various reactions and pathways reported in the literature.

Structural properties and anti-inflammatory activity of purified polysaccharides from Hen-of-the-woods mushrooms (Grifola frondosa)

Grifola frondosa is an edible medicinal mushroom that has been proven to have a variety of health benefits. The main active ingredients of this mushroom are polysaccharides. In this study, ultrasonic-assisted extraction was used to obtain crude Grifola frondosa polysaccharides (GFPs). Then, purified GFP was obtained after purification. The optimum extraction conditions were an extraction time of 71 min, an extraction temperature of 90°C in a solid-to-liquid ratio of 1:37 g/mL, and an ultrasonic power of 500 W. GFP was purified using DEAE-52 and Sephadex G-100. The structural characterization of GFP was performed using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), ion chromatography (IC), and ultraviolet (UV) visible photometry. The morphology of GFP was analyzed by scanning electron microscopy (SEM), thermogravimetric differential scanning calorimetry (TG-DSC), and Congo red testing. In addition, the administration of GFP in oxazolone (OXZ)-induced ulcerative colitis (UC) in mice was found to prevent weight loss. Different doses of GFP (80, 160, and 320 mg/kg body weight) were used, and sulfapyridine (SASP) was used as a positive control (370 mg/kg body weight) for the treatment of OXZ-induced UC. After treatment, the mice were killed, and blood and colon tissue samples were collected. GFP was found to prevent decreases in colon length and the levels of leukocytes, platelets, and neutrophils in UC mice. Moreover, GFP also decreased the expression of pro-inflammatory cytokines [tumor necrosis factor (TNF)-α and interleukin (IL)-1 β], increased IL-10, and reduced colon injury in UC mice. The results showed that Under these conditions, the predicted polysaccharide yield was 21.72%, and the actual extraction rate was 21.13%. The polysaccharide composition (molar ratio) was composed of fucose (0.025), glucosamine hydrochloride (0.004), galactose (0.063), glucose (0.869), and mannose (0.038). GFP was also found to have a typical absorption peak, and the GFP extracted using the ultrasound-assisted extraction protocol was mainly β-glucan. These results indicate that ultrasound-assisted extraction of GFP could reduce OXZ-induced intestinal inflammation as a promising candidate for the treatment of UC, with the potential for development as a food supplement to improve intestinal diseases.

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.

Physicochemical characteristics and biological activities of soluble dietary fibers isolated from the leaves of different quinoa cultivars

Quinoa leaf is consumed as a promising value-added vegetable in the diet. Although quinoa leaf is rich in soluble dietary fibers, the knowledge regarding their chemical structures and biological activities is still limited, which astricts their application in the functional food industry. Thus, to improve the precise use and application of soluble dietary fibers (SDFs) isolated from quinoa leaves in the food industry, the physicochemical structures and bioactivities of SDFs isolated from different quinoa leaves were systematically investigated. Results indicated that quinoa leaves were rich in SDFs, ranging from 3.30 % to 4.55 % (w/w). Quinoa SDFs were mainly composed of acidic polysaccharides, such as homogalacturonan and rhamnogalacturonan I, which had the molecular weights in the range of 4.228 × 10⁴ -7.059 × 10⁴ Da. Besides, quinoa SDFs exerted potential in vitro antioxidant activities, lipid and bile acid-adsorption capacities, immunoregulatory activities, and prebiotic effects, which might be partially associated with their molecular mass, content of uronic acid, and content of bound polyphenol. Collectively, these findings are beneficial to better understanding the chemical structures and bioactivities of SDFs extracted from different quinoa leaves, which can also provide a scientific basis for developing quinoa SDFs into functional foods in the food industry.

Protective Effect of Flavonoids from Mulberry Leaf on AAPH-Induced Oxidative Damage in Sheep Erythrocytes

To evaluate the antioxidant activity of flavonoids extracted from Chinese herb mulberry leaves (ML), flavonoids from mulberry leaves (FML) were extracted and purified by using ultrasonic-assisted enzymatic extraction and D101 macroporous resin. Using LC-MS/MS-Liquid Chromatography with tandem mass spectrometry analysis, hesperidin, rutoside, hyperoside, cyanidin-3-o-glucoside, myricitrin, cyanidin, and quercetin were identified, and NMR and UV were consistent with the verification of IR flavonoid characteristics. The antioxidant activity of FML has also been evaluated as well as the protective effect on 2,2 0-azobis (2-amidinopropane) dihydrochloride (AAPH)-induced oxidative stress. The results showed that FML exhibited powerful antioxidant activity. Moreover, FML showed dose-dependent protection against AAPH-induced sheep erythrocytes’ oxidative hemolysis. In the enzymatic antioxidant system, pretreatment with high FML maintained the balance of SOD, CAT, and GSH-Px; in the non-enzymatic antioxidant system, the content of MDA can be effectively reduced after FML treatment. This study provides a research basis for the development of natural products from mulberry leaves.

Enrichment of Agar Gel with Antioxidant Pectin from Fireweed: Mechanical and Rheological Properties, Simulated Digestibility, and Oral Processing

The aims of the study were to evaluate the influence of pectin isolated from fireweed (FP) on the mechanical and rheological properties of agar (A) gel, to investigate the release of phenolic compounds (PCs) and pectin from A-FP gels at simulated digestion in vitro, and to evaluate the oral processing and sensory properties of A-FP gels. The hardness of A-FP gels decreased gradually with the increase in the concentration of FP added (0.1, 0.4, and 1.6%). The hardness of A-FP1.6 gel was 41% lower than A gel. Rheological tests found A gel was a strong physical gel (storage modulus (G′) >>loss modulus (G″)), and the addition of FP up to 1.6% did not significantly change its G’. The G″ value decreased in A-FP gels compared to A gel. The release of galacturonic acid (GalA) was 3.4 ± 0.5, 0.5 ± 0.2, 2.4 ± 1.0, and 2.2 ± 0.7 mg/mL after digestion of A-FP1.6 gel in the oral in vivo phase (OP) and subsequent incubation in simulated gastric (SGF), intestinal (SIF), and colonic (SCF) fluids in vitro. The incubation medium after OP, SGF, and SIF digestion of A-FP1.6 contained 24−64 μg GAE/mL of PCs, while SCF contained 144 μg GAE/mL, supposing a predominant release of antioxidant activity from the gel in the colon. Chewing to readiness for swallowing A-FP gel required less time and fewer chews with less activity of the masseter and temporalis muscles. A-FP1.6 gel had a lower likeness score for taste and consistency and a similar score for appearance and aroma when compared with A gel. Thus, A-FP gels were weakened compared to A gel and required less time and muscle activity for oral processing. A-FP gel had antioxidant activity due to the PCs associated with pectin, while A gel had no antioxidant activity.

Polysaccharides of Salsola passerina: Extraction, Structural Characterization and Antioxidant Activity

The above-ground part of the Salsola passerine was found to contain ~13% (w/w) of polysaccharides extractable with water and aqueous solutions of ammonium oxalate and sodium carbonate. The fractions extracted with aqueous sodium carbonate solutions had the highest yield. The polysaccharides of majority fractions are characterized by similar monosaccharide composition; namely, galacturonic acid and arabinose residues are the principal components of their carbohydrate chains. The present study focused on the determination of antioxidant activity of the extracted polysaccharide fractions and elucidation of the structure of polysaccharides using nuclear magnetic resonance (NMR) spectroscopy. Homogalacturonan (HG), consisting of 1,4-linked residues of α-D-galactopyranosyluronic acid (GalpA), rhamnogalacturonan-I (RG-I), which contains a diglycosyl repeating unit with a strictly alternating sequence of 1,4-linked D-GalpA and 1,2-linked L-rhamnopyranose (Rhap) residues in the backbone, and arabinan, were identified as the structural units of the obtained polysaccharides. HMBC spectra showed that arabinan consisted of alternating regions formed by 3,5-substituted and 1,5-linked arabinofuranose residues, but there was no alternation of these residues in the arabinan structure. Polysaccharide fractions scavenged the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical at 0.2-1.8 mg/mL. The correlation analysis showed that the DPPH scavenging activity of polysaccharide fractions was associated with the content of phenolic compounds (PCs).

Extraction, Physicochemical Properties, Anti-Aging, and Antioxidant Activities of Polysaccharides from Industrial Hemp Residues

A large amount of hemp polysaccharides remain in industrial hemp residues (IHR) after cannabidiol extraction, resulting in the waste of resources. Therefore, the systematic study of hemp polysaccharides is beneficial to the development of IHR in the future. In this study, the extraction of industrial hemp residues polysaccharide (IHRPs) was optimized by single-factor experiment and orthogonal experimental design. The optimum heating extraction conditions were extraction temperature 98 °C, solid–liquid ratio 1:10, extraction time 1 h, number of successive extractions 2, and pH at 4. The extraction ratio and the polysaccharide content were 20.12 ± 0.55% and 12.35 ± 0.26% at the conditions, respectively. Besides, the best alcohol precipitation conditions were pumping with 2 L/h, stirring continuously, and ice-water bath for 4 h. The crude IHRPs was further purified by column chromatography and the polysaccharide/protein contents of purified IHRPs were 34.44% and 1.61%. IHRPs was mainly made up of ten monosaccharides and some non-sugar components including organic acids, flavonoids, steroids, and glycoside. The FT-IR demonstrated the polysaccharide skeleton of IHRPs. Moreover, the DPPH and ABTS scavenging rate of IHRPs were 76.00% and 99.05% at the concentrations of 1 mg/mL. IHRPs could promote the epidermal cells proliferation and healing of cell scratches. Meanwhile, IHRPs could promoted the expression of anti-aging-related genes. Overall, IHRPs could be a desirable natural source of antioxidants and anti-aging products in many aspects.

Physicochemical Characteristics and Antidiabetic Properties of the Polysaccharides from Pseudostellaria heterophylla

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

Crude Polysaccharide Extracted From Moringa oleifera Leaves Prevents Obesity in Association With Modulating Gut Microbiota in High-Fat Diet-Fed Mice

Moringa oleifera is a commonly used plant with high nutritional and medicinal values. M. oleifera leaves are considered a new food resource in China. However, the biological activities of M. oleifera polysaccharides (MOP) in regulating gut microbiota and alleviating obesity remain obscure. In the present study, we prepared the MOP and evaluated its effects on obesity and gut microbiota in high-fat diet (HFD)-induced C57BL/6J mice. The experimental mice were supplemented with a normal chow diet (NCD group), a high-fat diet (HFD group), and HFD along with MOP at a different dose of 100, 200, and 400 mg/kg/d, respectively. Physiological, histological, biochemical parameters, genes related to lipid metabolism, and gut microbiota composition were compared among five experimental groups. The results showed that MOP supplementation effectively prevented weight gain and lipid accumulation induced by HFD, ameliorated blood lipid levels and insulin resistance, alleviated the secretion of pro-inflammatory cytokines, and regulated the expression of genes related to lipid metabolism and bile acid metabolism. In addition, MOP positively reshaped the gut microbiota composition, significantly increasing the abundance of Bacteroides, norank_f_Ruminococcaceae, and Oscillibacter, while decreasing the relative abundance of Blautia, Alistipes, and Tyzzerella, which are closely associated with obesity. These results demonstrated that MOP supplementation has a protective effect against HFD-induced obesity in mice, which was associated with reshaping the gut microbiota. To the best of our knowledge, this is the first report on the potential of MOP to prevent obesity and modulating gut microbiota, which suggests that MOP can be used as a potential prebiotic.

Study on the interaction of Hericium erinaceus mycelium polysaccharides and its degradation products with food additive silica nanoparticles

Gastric mucosal injury is a common gastrointestinal disorder. Hericium erinaceus polysaccharide, the major active ingredient in Hericium erinaceus, can reduce gastric mucosal damage to some extent. In this study, two different products HMP-Vc and HMP-Ce were obtained by Vitamin C and cellulase degradation of Hericium erinaceus mycelium polysaccharide (HMP). The gastroprotective activity of polysaccharides and its interaction products with food additives silica nanoparticles (nSiO2) were studied in GES-1 cells. It was found that gastroprotective activity of HMP was significantly higher than that of degradation products, and the addition of nSiO2 could enhance this activity of HMP. The greatest difference between the degradation products and HMP was the reduction of the triple helix structure, which might be the reason of the gastroprotective activity was less than that of HMP. Moreover, nSiO2 might interact with HMP through hydrogen bonding to enhance its activity.

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.

Effects of simulated digestion in vitro on the structure and macrophages activation of fucoidan from Sargassum fusiforme

Molecular size and spatial structure affect the bioactivities of polysaccharides. SFF is a fucoidan extracted from Sargassum fusiforme. The possible changes of SFF affected by gastrointestinal tract and subsequently changes of its physicochemical property or its bioactivity have yet to be systematically investigated. Our results showed that DSFF, the gastrointestinal digestion product of SFF, has increased reducing sugar content, increased proportion of low molecular weight components, and a more clustered island-like morphology. Both SFF and DSFF activate RAW 264.7 macrophages evidenced by the increasing level of NO, intracellular ROS, and macrophages cytokines. Further investigation showed that DSFF induced M1 phenotype polarization in RAW 264.7 cells. DSFF also showed stronger macrophage activation and phenotype polarization than SFF. Our present work showed that SFF could be digested by simulated gastrointestinal environment in vitro and the digested product DSFF showed higher efficiency in macrophages activation and phenotype polarization.

Physicochemical properties, structural characterization and biological activities of polysaccharides from quinoa (Chenopodium quinoa Willd.) seeds

In this paper, membrane separation technology was employed to separate polysaccharide fractions from the water extract of quinoa seeds. The chemical composition, structure characteristic and morphology were analyzed by chemical methods and instrumental analysis including HPLC-DAD, UV, FT-IR, Congo red test, SEM, AFM, XRD, TGA and NMR. Results indicated that three polysaccharide fractions named as QPs-I, QPs-II and QPs-III were successfully separated using microfiltration and ultrafiltration membrane with MWCO of 300 and 10 kDa in sequence. The Mw and polysaccharide content of three fractions were QPs-I (4609 Da, 33.75%), QPs-II (15,932 Da, 45.31%) and QPs-III (960,895 Da, 34.65%), respectively. The polysaccharide in three fractions was heteropolysaccharide that mainly consisted of glucose, galactose and arabinose, with their combined monosaccharide percentage being 91.17% in QPs-I, 87.81% in QPs-II, and 91.72% in QPs-III, respectively. All three polysaccharide fractions contained triple-helix structure. Biological experiment showed that antioxidant and antidiabetic activities in dose-dependent manners and also revealed immunoregulatory activity on RAW264.7 cells. These results indicated that QPs has the potential to be used in a natural agent in antioxidant, antidiabetic and immunoregulation functional food.

Potential prebiotic properties of exopolysaccharides produced by a novel Lactobacillus strain, Lactobacillus pentosus YY-112

Exopolysaccharides (EPSs) derived from Lactobacilli have important physiological effects and are commonly used as new prebiotics. We identified and studied a new Lactobacillus strain, YY-112, isolated from waxberry (Myrica rubra). This strain, identified as Lactobacillus pentosus, tolerates acids, bile salts, and artificial digestive fluids. The EPS derived from this strain weighed 5.9 × 10⁴ Da and contained glucose, mannose, glucosamine, galactose, and rhamnose at 62.69 : 85.85 : 2.46 : 2.92 : 1.00 molar ratios. We found that the EPS from this strain increased the ratio of Bacteroidetes to Firmicutes and decreased the relative abundance of Proteobacteria, especially Escherichia-Shigella, when added to a simulated gastrointestinal system in vitro. After analysing the short-chain fatty acids, we found that this EPS promoted the production of acetic acid, propionic acid, and butyric acid, and reduced the ratio of acetic acid to propionic acid. We conclude that Lactobacillus pentosus YY-112 is a potential probiotic strain with EPS that is beneficial for the intestinal microbiota and short-chain fatty acid production.