A pectic polysaccharide from water decoction of Xinjiang Lycium barbarum fruit protects against intestinal endoplasmic reticulum stress

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.

Mulberry Leaf Polysaccharides Attenuate Oxidative Stress Injury in Peripheral Blood Leukocytes by Regulating Endoplasmic Reticulum Stress

The present study assessed the protective effects and underlying mechanisms of mulberry leaf polysaccharides (MLPs) against hydrogen peroxide (H2O2)-induced oxidative stress injury in the peripheral blood leukocytes (PBLs) of Megalobrama amblycephala. Five treatment groups were established in vitro: the NC group (PBLs incubated in an RPMI-1640 complete medium for 4 h), the HP group (PBLs incubated in an RPMI-1640 complete medium for 3 h, and then stimulated with 100 μM of H2O2 for 1 h), and the 50/100/200-MLP pre-treatment groups (PBLs were pre-treated with MLPs (50, 100, and 200 μg/mL) for 3 h, and then stimulated with 100 μM of H2O2 for 1 h). The results showed that MLP pre-treatment dose-dependently enhanced PBLs' antioxidant capacities. The 200 μg/mL MLP pre-treatment effectively protected the antioxidant system of PBLs from H2O2-induced oxidative damage by reducing the malondialdehyde content and lactic dehydrogenase cytotoxicity, and increasing catalase and superoxide dismutase activities (p < 0.05). The over-production of reactive oxygen species, depletion of nicotinamide adenine dinucleotide phosphate, and collapse of the mitochondrial membrane potential were significantly inhibited in the 200-MLP pre-treatment group (p < 0.05). The expressions of endoplasmic reticulum stress-related genes (forkhead box O1α (foxO1α), binding immunoglobulin protein (bip), activating transcription factor 6 (atf6), and C/EBP-homologous protein (chop)), Ca2+ transport-related genes (voltage-dependent anion-selective channel 1 (vdac1), mitofusin 2 (mfn2), and mitochondrial Ca2+ uniporter (mcu)), and interleukin 6 (il-6) and bcl2-associated x (bax) were significantly lower in the 200-MLP pre-treatment group than in the HP group (p < 0.05), which rebounded to normal levels in the NC group (p > 0.05). These results indicated that MLP pre-treatment attenuated H2O2-induced PBL oxidative damage in the M. amblycephala by inhibiting endoplasmic reticulum stress and maintaining mitochondrial function. These findings also support the possibility that MLPs can be exploited as a natural dietary supplement for M. amblycephala, as they protect against oxidative damage.

Natural polysaccharides protect against diet-induced obesity by improving lipid metabolism and regulating the immune system

Unhealthy dietary patterns-induced obesity and obesity-related complications pose a great threat to human health all over the world. Accumulating evidence suggests that the pathophysiology of obesity and obesity-associated metabolic disorders is closely associated with dysregulation of lipid and energy metabolism, and metabolic inflammation. In this review, three potential anti-obesity mechanisms of natural polysaccharides are introduced. Firstly, natural polysaccharides protect against diet-induced obesity directly by improving lipid and cholesterol metabolism. Since the immunity also affects lipid and energy metabolism, natural polysaccharides improve lipid and energy metabolism by regulating host immunity. Moreover, diet-induced mitochondrial dysfunction, prolonged endoplasmic reticulum stress, defective autophagy and microbial dysbiosis can disrupt lipid and/or energy metabolism in a direct and/or inflammation-induced manner. Therefore, natural polysaccharides also improve lipid and energy metabolism and suppress inflammation by alleviating mitochondrial dysfunction and endoplasmic reticulum stress, promoting autophagy and regulating gut microbiota composition. Specifically, this review comprehensively summarizes underlying anti-obesity mechanisms of natural polysaccharides and provides a theoretical basis for the development of functional foods. For the first time, this review elucidates anti-obesity mechanisms of natural polysaccharides from the perspectives of their hypolipidemic, energy-regulating and immune-regulating mechanisms.

Current progress in the hypoglycemic mechanisms of natural polysaccharides

Unhealthy dietary pattern-induced type 2 diabetes mellitus poses a great threat to human health all over the world. Accumulating evidence has revealed that the pathophysiology of type 2 diabetes mellitus is closely associated with the dysregulation of glucose metabolism and energy metabolism, serious oxidative stress, prolonged endoplasmic reticulum stress, metabolic inflammation and intestinal microbial dysbiosis. Most important of all, insulin resistance and insulin deficiency are two key factors inducing type 2 diabetes mellitus. Nowadays, natural polysaccharides have gained increasing attention owing to their numerous health-promoting functions, such as hypoglycemic, energy-regulating, antioxidant, anti-inflammatory and prebiotic activities. Therefore, natural polysaccharides have been used to alleviate diet-induced type 2 diabetes mellitus. Specifically, this review comprehensively summarizes the underlying hypoglycemic mechanisms of natural polysaccharides and provides a theoretical basis for the development of functional foods. For the first time, this review elucidates hypoglycemic mechanisms of natural polysaccharides from the perspectives of their regulatory effects on glucose metabolism, insulin resistance and mitochondrial dysfunction.

The Role of Seaweed Polysaccharides in Gastrointestinal Health: Protective Effect against Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a prominent global public health issue. Anti-inflammatory medications, immunosuppressants, and biological therapies are currently used as treatments. However, they are often unsuccessful and have negative consequences on human health. Thus, there is a tremendous demand for using natural substances, such as seaweed polysaccharides, to treat IBD's main pathologic treatment targets. The cell walls of marine algae are rich in sulfated polysaccharides, including carrageenan in red algae, ulvan in green algae, and fucoidan in brown algae. These are effective candidates for drug development and functional nutrition products. Algal polysaccharides treat IBD through therapeutic targets, including inflammatory cytokines, adhesion molecules, intestinal epithelial cells, and intestinal microflora. This study aimed to systematically review the potential therapeutic effects of algal polysaccharides on IBD while providing the theoretical basis for a nutritional preventive mechanism for IBD and the restoration of intestinal health. The results suggest that algal polysaccharides have significant potential in complementary IBD therapy and further research is needed for fully understanding their mechanisms of action and potential clinical applications.

Pectic polysaccharides derived from Hainan Rauwolfia ameliorate NLR family pyrin domain-containing 3-mediated colonic epithelial cell pyroptosis in ulcerative colitis

Pectic polysaccharides (PPs) could exert functions on ulcerative colitis (UC), which is classified as a nonspecific inflammatory disorder. This study investigated the molecular mechanism of PPs derived from Rauwolfia in UC. First, the dextran sodium sulfate (DSS)-induced mouse colitis models and lipopolysaccharide (LPS)-treated colonic epithelial cell (YAMC) models were established and treated with PP. Subsequently, the effects of PPs on mucosal damages in DSS mice were detected, and the levels of inflammatory cytokines, pyroptosis-related factors, oxidative stress-related markers, and the tight junction-related proteins in the tissues or cells were examined, and the results suggested that PPs ameliorated colonic mucosal damages and cell pyroptosis in DSS mice, and limited colonic epithelial cell pyroptosis in in vitro UC models. Subsequently, the binding relations of retinol-binding protein 4 (RBP4) to miR-124-3p and NLR pyrin domain-containing 3 (NLRP3) were analyzed. miR-124-3p targeted RBP4 and reduced the binding of RBP4 to NLRP3, thus inhibiting NLRP3-mediated pyroptosis. Finally, functional rescue experiments revealed that miR-124-3p suppression or RBP4 overexpression promoted colonic epithelial cell pyroptosis. Collectively, Rauwolfia-derived PPs limited miR-124-3p and targeted RBP4 and reduced the binding potency of RBP4 to NLRP3 to inhibit NLRP3-mediated pyroptosis, resulting in the alleviation of colonic epithelial cell pyroptosis and mucosal damages in UC.

Recent progress of Lycium barbarum polysaccharides on intestinal microbiota, microbial metabolites and health: a review

Intestinal microbiota is symbiotically associated with host health, learning about the characteristics of microbiota and the factors that modulate it could assist in developing strategies to promote human health and prevent diseases. Polysaccharides from Lycium barbarum (LBPs) are found beneficial for enhancing the activity of gut microbiota, as a potential prebiotic, which not only participates in improving body immunity, obesity, hyperlipidemia and systemic inflammation induced by oxidative stress, but also plays a magnificent role in regulating intestinal microenvironment and improving host health and target intestinal effects via its biological activities, as well as gut microbiota and metabolites. To highlight the internal relationship between intestinal microbiota and LBPs, this review focuses on the latest advances in LBPs on the intestinal microbiota, metabolites, immune regulation, intestinal barrier protection, microbiota-gut-brain axis and host health. Moreover, the preparation, structure, bioactivity and modification of LBPs were also discussed. This review may offer new perspective on LBPs improving health of gut and host via intestinal microbiota, and provide useful guidelines for the application of LBPs in the food industry.

Structural features and antioxidant activities of polysaccharides from different parts of Codonopsis pilosula var. modesta (Nannf.) L. T. Shen

In this study, three acidic polysaccharides from different plant parts of Codonopsis pilosula var. Modesta (Nannf.) L. T. Shen were obtained by ion exchange chromatography and gel filtration chromatography, and the yields of these three polysaccharides were different. According to the preliminary experimental results, the antioxidant activities of the polysaccharides from rhizomes and fibrous roots (CLFP-1) were poor, and was thus not studied further. Due to this the structural features of polysaccharides from roots (CLRP-1) and aerial parts (CLSP-1) were the object for this study and were structurally characterized, and their antioxidant activities were evaluated. As revealed by the results, the molecular weight of CLRP-1and CLSP-1 were 15.9 kDa and 26.4 kDa, respectively. The monosaccharide composition of CLRP-1 was Ara, Rha, Fuc, Xyl, Man, Gal, GlcA, GalA in a ratio of 3.8: 8.4: 1.0: 0.8: 2.4: 7.4: 7.5: 2.0: 66.7, and Ara, Rha, Gal, GalA in a ratio of 5.8: 8.9: 8.0: 77.0 in for CLSP-1. The results of structural elucidation indicated that both CLRP-1 and CLSP-1 were pectic polysaccharides, mainly composed of 1, 4-linked galacturonic acid with long homogalacturonan regions. Arabinogalactan type I and arabinogalactan type II were presented as side chains. The antioxidant assay in IPEC-J2 cells showed that both CLRP-1 and CLSP-1 promoted cell viability and antioxidant activity, which significantly increase the level of total antioxidant capacity and the activity of superoxide dismutase, catalase, and decrease the content of malondialdehyde. Moreover, CLRP-1 and CLSP-1 also showed powerful antioxidant abilities in Caenorhabditis elegans and might regulate the nuclear localization of DAF-16 transcription factor, induced antioxidant enzymes activities, and further reduced reactive oxygen species and malondialdehyde contents to increase the antioxidant ability of Caenorhabditis elegans. Thus, these finding suggest that CLRP-1 and CLSP-1 could be used as potential antioxidants.

Polysaccharide-Based Edible Gels as Functional Ingredients: Characterization, Applicability, and Human Health Benefits

Nowadays, edible materials such as polysaccharides have gained attention due to their valuable attributes, especially gelling property. Polysaccharide-based edible gels (PEGs) can be classified as (i) hydrogels, (ii) oleogels and bigels, (iii) and aerogels, cryogels and xerogels, respectively. PEGs have different characteristics and benefits depending on the functional groups of polysaccharide chains (e.g., carboxylic, sulphonic, amino, methoxyl) and on the preparation method. However, PEGs are found in the incipient phase of research and most studies are related to their preparation, characterization, sustainable raw materials, and applicability. Furthermore, all these aspects are treated separately for each class of PEG, without offering an overview of those already obtained PEGs. The novelty of this manuscript is to offer an overview of the classification, definition, formulation, and characterization of PEGs. Furthermore, the applicability of PEGs in the food sector (e.g., food packaging, improving food profile agent, delivery systems) and in the medical/pharmaceutical sector is also critically discussed. Ultimately, the correlation between PEG consumption and polysaccharides properties for human health (e.g., intestinal microecology, "bridge effect" in obesity, gut microbiota) are critically discussed for the first time. Bigels may be valuable for use as ink for 3D food printing in personalized diets for human health treatment. PEGs have a significant role in developing smart materials as both ingredients and coatings and methods, and techniques for exploring PEGs are essential. PEGs as carriers of bioactive compounds have a demonstrated effect on obesity. All the physical, chemical, and biological interactions among PEGs and other organic and inorganic structures should be investigated.

Lycium Genus Polysaccharide: An Overview of its Extraction, Structures, Pharmacological Activities and Biological Applications

Polysaccharide is considered to be the main active ingredient of the genus Lycium L., which is taken from the dried fruit of the famous Chinese herbal medicine and precious tonic known as wolfberry. Traditional uses include nourishing the liver and kidney and improving eyesight, with widespread use in the clinical practice of traditional Chinese medicine. Many studies have focused on the isolation and identification of the genus Lycium L. polysaccharide and its biological activities. However, the variety of raw materials and the mechanisms of polysaccharides differ. After extraction, the structure and biological activity of the obtained polysaccharides also differ. To date, approximately 58 kinds of polysaccharides have been isolated and purified from the Lycium genus, including water-soluble polysaccharides; homogeneous polysaccharides; pectin polysaccharides; acidic heteropolysaccharides; and arabinogalactans, which are composed of arabinose, glucosamine, galactose, glucose, xylose, mannose, fructose, ribose, galacturonic acid, and glucuronic acid. Pharmacological studies have shown that LBPs exhibit a variety of important biological activities, such as protection of nerves; promotion of reproduction; and anti-inflammatory, hepatoprotective, hypoglycemic, and eyesight-improving activities. The aim this paper is to summarize previous and current references to the isolation process, structural characteristics, and biological activities of the genus Lycium L. polysaccharide. This review will provide a useful reference for further research and application of the genus Lycium L. polysaccharide in the field of functional food and medicine.

Effect of Bergamot and Laoxianghuang Polysaccharides on Gut Microbiota Derived from Patients with Hyperlipidemia: An Integrative Analysis of Microbiome and Metabolome during In Vitro Fermentation

The aim of this study was to investigate the effects of bergamot polysaccharide (BP) and Laoxianghuang polysaccharides (LPs, fermented bergamot) on the microbiome and metabolome during the in vitro fermentation of gut microbiota from patients with hyperlipidemia. Results indicated that both BP and LPs were able to increase the production of acetic acid, propionic acid, and butyric acid. However, only LPs could decrease the content of isobutyric acid and isovaleric acid, which are detrimental to gut health. A 16S rRNA analysis showed that both BP and LPs could reduce the proportion of Fusobacterium, whereas they increased the Bacteroides content in hyperlipidemia. Untargeted UPLC-MS/MS metabolomic profiling found six bio-markers that were significantly changed after BP and LPs intervention, and four of the down-regulated metabolites were long-chain fatty acids associated with vascular diseases. These findings provide new evidence that BP and LPs have the potential to regulate imbalances in the gut microbiota in patients with hyperlipidemia and ameliorate its metabolic abnormalities.

Structure and immunological activity of an arabinan-rich acidic polysaccharide from Atractylodes lancea (Thunb.) DC

An arabinan-rich acidic polysaccharide, named ALP4-2 ([α]20 D = +197.8 (c 1.0 mg/mL, H₂O); and M_w = 5.59 × 10³ g/mol), was obtained from Atractylodes lancea (Thunb.) DC. ALP4-2 is mainly comprised of Ara along with a small amount of GalA, Gal, Rha, Glc and Xyl. The structure was decorated by glycosidic linkages of α-Araf-(1→, →3)-α-Araf-(1→, →5)-α-Araf-(1→, →3,5)-α-Araf-(1→, →2,4)-α-Rhap-(1→, α-GalAp-(1→, →4)-α-GalAp-6-OMe-(1→, →4)-α-GalAp-6-OMe and β-Galp-(1→ with a ratio of 6:1:7:5:5:1:7:1:4. The structure, configuration and microstructure of ALP4-2 was proposed by comprehensive considerations of results from SEC-MALLS-RID, SEC-HRMS, GC-MS, and 1D/2D NMR spectroscopy. Except for a high methyl ester in full pectin regions, an abundant arabinan moiety is observed in ALP4-2 with highly complex and branched characteristics. The immunoactivity displayed that ALP4-2 can significantly promote phagocytosis of macrophage without cytotoxicity, and stimulate nitric oxide and cytokines (TNF-α, IL-6 and IL-10) release on RAW 264.7.

The potential roles of natural plant polysaccharides in inflammatory bowel disease: A review

Inflammatory bowel disease (IBD) is a long-term chronic disease, about 20% of IBD patients deteriorate to colorectal cancer. Currently, there is no radical cure for IBD. Natural plant polysaccharides (NPP) have low toxic and side effects, which have immune and prebiotic activities and possesses positive effect on alleviating IBD. In this review, we will focus on the alleviating effect of NPP on IBD in vitro and in vivo from three aspects: regulating intestinal flora imbalance, repairing intestinal barrier injury and improving immunity. The relationship between the chemical structure of natural plant polysaccharides and the therapeutic effect of IBD are highlighted. Finally, the synergistic role of NPP as a carrier of drugs or active molecules to reduce side effects and enhance targeting function are discussed, especially pectic polysaccharides. Broadly, this review provides a valuable reference for NPP to be developed as functional food or health products to alleviate IBD.

Asymmetric barrier membranes based on polysaccharide micro-nanocomposite hydrogel: Synthesis, characterization, and their antibacterial and osteogenic activities

Guided tissue regeneration (GTR) strategies enable periodontal tissue regeneration, generally by providing barrier membranes. However, currently available membranes have limited osteoconductive and antibacterial potential. To address these challenges, we fabricated a new asymmetric barrier membrane. Agarose hydrogel functions as the main body of the barrier membrane. Hollow carbonated hydroxyapatite (CHA) prepared by hydrothermal method, was sedimented in agarose to exhibit an asymmetrical structure. And ε-poly-lysine (ε-PLL) was chosen as an antimicrobial agent to equip the membrane with long-lasting antibacterial activity. With the increased dose of CHA addition, the barrier membrane shows better biocompatibility, and higher mechanical properties. We demonstrated the osteoconductivity and antibacterial properties of the membrane in vitro and in vivo. In summary, our findings suggest that the barrier membrane has good osteoconductive and antibacterial properties, indicating its potential for periodontal tissue engineering.

Pharmacokinetics and Excretion Study of Lycium barbarum Polysaccharides in Rats by FITC-Fluorescence Labeling

A high-performance gel permeation chromatography fluorescence detection (HPGPC-FD) method combined with fluorescein isothiocyanate (FITC) labeling was established for the microanalysis of L. barbarum polysaccharides (LBP). The calibration curves linear over the range of 0.2–20 µg/mL in rat plasma, and 0.25–500 μg/mL in urine and feces samples with correlation coefficients greater than 0.99. The inter-day and intra-day precisions (RSD, %) of the method were under 15% with the relative recovery ranging from 84.6% to 104.0% and the RSD ranging from 0.47% to 7.28%. The concentration–time curve of LBP-FITC in plasma following intragastric administration at 100, 50 and 25 mg/kg well fitted to a nonlinear model. LBP-FITC slowly eliminated from plasma according to the long half-lives (t_1/2 = 31.39, 38.09, and 45.76 h, respectively) and mean retention times (MRT_0–t = 18.38, 19.15 and 20.07 h, respectively; AUC_0–∞ = 230.49, 236.18 and 242.57 h, respectively) after administration of LBP-FITC at doses of 100, 50, and 25 mg/kg, respectively. After intragastric administration at 50 mg/kg for 72 h, the concentration of LBP-FITC in urine and feces was 0.09 ± 0.04% and 92.18 ± 3.61% respectively; the excretion rate of urine was the highest in 0–4 h period and decreased continuously in 4–24 h period. The excretion rate of feces was the highest in 4–10 h, 48.28 ± 9.349% in feces within 4–10 h, and decreased rapidly in 10–24 h. The present study showed that LBP was absorbed as its prototype and most proportion of LBP was excreted from feces, indicating a long time remaining in intestine.

Multi-Pharmaceutical Activities of Chinese Herbal Polysaccharides in the Treatment of Pulmonary Fibrosis: Concept and Future Prospects

Pulmonary fibrosis is a fatal chronic progressive respiratory disease, characterized by continuous scarring of the lung parenchyma, leading to respiratory failure and death. The incidence of PF has increased over time. There are drugs, yet, there are some limitations. Hence, it is of importance to find new therapies and new drugs to replace the treatment of pulmonary fibrosis. In recent years, there have been a great number of research reports on the treatment of traditional Chinese medicine polysaccharides in various system fields. Among them, the treatment of PF has also gained extensive attention. This review summarized the source of polysaccharides, the drug activity of traditional Chinese medicine, and the protective effects on targets of Pulmonary fibrosis. We hope it can inspire researchers to design and develop polysaccharides, serving as a reference for potential clinical therapeutic drugs.

A homogeneous polysaccharide from Lycium barbarum: Structural characterizations, anti-obesity effects and impacts on gut microbiota

Lycium barbarum polysaccharides (LBPs) are known for their beneficial effects on diabetes, NAFLD and related chronic metabolic diseases induced by high-fat diet (HFD). However, the relevant researches are mainly about the whole crude polysaccharides, the specific active ingredient of LBPs and its bioactivity have been rarely explored. Herein, a homogeneous polysaccharide (LBP-W) was isolated and purified from crude LBPs. Structure characterizations indicated that LBP-W contained a main chain consisting of a repeated unit of →6)-β-Galp(1 → residues with branches composed of α-Araf, β-Galp and α-Rhap residues at position C-3. The objective of this study was to evaluate the anti-obesogenic effect of LBP-W and figure out the underlying mechanisms. In vivo efficacy trial illustrated that LBP-W supplements can alleviate HFD-induced mice obesity significantly. Gut microbiota analysis showed that LBP-W not only improved community diversity of intestinal flora, but also regulated their specific genera. Moreover, LBP-W can increase the content of short-chain fatty acids (SCFAs), a metabolite of the intestinal flora. In summary, all these results demonstrated that the homogeneous polysaccharide purified from L. barbarum could be used as a prebiotic agent to improve obesity by modulating the composition of intestinal flora and the metabolism of SCFAs.

ε‑Polylysine-stabilized agarose/polydopamine hydrogel dressings with robust photothermal property for wound healing

Polydopamine (PDA) is emerging as an attractive photothermal agent due to its good photothermal performance and excellent biocompatibility. However, without chemical modification, PDA is normally unstable and usually leached out from the constructed biomaterials, realistically limiting its application space. Here, we constructed a new hydrogel dressing with robust and stable photothermal performance by introduction of ε-Polylysine (ε-PL) into agarose/PDA matrix to efficiently lock PDA. By optimizing PDA/ε-PL rational dose in agarose network structure, a hybrid agarose/PDA/ε-PL hydrogel (ADPH) with stable photothermal functionality and desirable physicochemical properties could be achieved. ADPH possessed satisfactory microbicidal efficacy in vivo, which enabled the bacteria-infected skin wound to be cured quickly by successful suppressing inflammation, accelerating collagen deposition and promoting angiogenesis in a bacterial-infected wound model. Collectively, this study illustrates a simple, convenient but powerful strategy to design functionally stable ADPH dressing for treating dermal wounds, which could open vistas in clinical wound management.

Pectic polysaccharides from edible halophytes: Insight on extraction processes, structural characterizations and immunomodulatory potentials

The preparation, chemical properties and bio-activities of polysaccharides derived from halophytes have gained an increasing interest in the past few years. Phytochemical and pharmacological reports have shown that carbohydrates are important biologically active compounds of halophytes with numerous biological potentials. It is believed that the mechanisms involved in these bio-activities are due to the modulation of immune system. The main objective of this summary is to appraise available literature of a comparative study on the extraction, structural characterizations and biological potentials, particularly immunomodulatory effects, of carbohydrates isolated from halophytes (10 families). This review also attempts to discuss on bioactivities of polysaccharides related with their structure-activity relationship. Data indicated that the highest polysaccharides yield of around 35% was obtained under microwave irradiation. Structurally, results revealed that the most of extracted carbohydrates are pectic polysaccharides which mainly composed of arabinose (from 0.9 to 72%), accompanied by other monosaccharides (galactose, glucose, rhamnose, mannose and xylose), significant amounts of uronic acids (from 18.9 to 90.1%) and some proportions of fucose (from 0.2 to 8.3%). The molecular mass of these pectic polysaccharides was varied from 10 to 2650 kDa. Hence, the evaluation of these polysaccharides offers a great opportunity to discover novel therapeutic agents that presented especially beneficial immunomodulatory properties. Moreover, reports indicated that uronic acids, molecular weights, as well as the presence of sulfate and unmethylated acidic groups may play a significant role in biological activities of carbohydrates from halophyte species.

The Effect of Different Extraction Conditions on the Physical Properties, Conformation and Branching of Pectins Extracted from Cucumis melo Inodorus

The extraction of pectin involves the physico-chemical hydrolysis and solubilisation of pectic polymers from plant tissues under the influence of several processing parameters. In this study, an experimental design approach was used to examine the effects of extraction pH, time and temperature on the pectins extracted from Cucumis melo Inodorus. Knowledge of physical properties (intrinsic viscosity and molar mass), dilute solution conformation (persistence length and mass per unit length), together with chemical composition, was then used to propose a new method, which can estimate the length and number of branches on the pectin RG-I region. The results show that physical properties, conformation and the length and number of branches are sensitive to extraction conditions. The fitting of regression equations relating length and number of branches on the pectin RG-I region to extraction conditions can, therefore, lead to tailor-made pectins with specific properties for specific applications.

Construction of functional curdlan hydrogels with bio-inspired polydopamine for synergistic periodontal antibacterial therapeutics

Curdlan, a bacteria-derived polysaccharide resource, possesses substantial potential for periodontal antimicrobial delivery. Here, the facile engineering of a functionalized curdlan/polydopamine (PDA) composite hydrogels was reported. The physiochemical evaluations of composite hydrogels proved their tunable properties associated with concentration of PDA including pore size, rheological property and swelling behavior. We have systematically assessed biocompatibility in vitro and found these hydrogels toxicity-free. Moreover, photothermal performance upon near infrared light (NIR) exposure was conducted and eventually indicated the best matches for antibacterial application. The acetate chlorhexidine (CHX) was chosen as a model antimicrobial and the release profiles demonstrated the entrapped CHX could be triggered and nicely controlled by NIR. The optimized bacteriostatic rate reached 99.9 %. Overall, we aimed to provide new curdlan-based hydrogels for periodontal antibacterial treatment by combining photothermal effect and antimicrobial simultaneously.