Galacturonic Acid Research Articles

Towards a sustainable circular bioprocess: Pectic oligosaccharides (POS) enzymatic production using passion fruit peels

A bioprocess was designed using passion fruit peels for the enzymatic production of POS. For this purpose, three commercial pectinase complexes were tested, and one was selected based on the analysis of viscosity change and galacturonic acid release during the reaction. Operating conditions were further determined at laboratory and bench scale, including time and enzyme dosage. Subsequently, the bioprocess was validated at pilot scale in a 40 L reactor, obtaining a highly concentrated syrup with 73.3 g POS per 100 g total solids, and 22.6 g total POS per 100 g passion fruit peel processed. Thus, the technical feasibility of a bioprocess leading to the production of a potential prebiotic syrup was proven, contributing to the SDG 12-3, “reduce food losses along production and supply chains”. These findings highlight for the first time the utilization of passion fruit peels in creating a prebiotic POS syrup through an enzymatic process involving commercial complexes. The straightforward nature of the bioprocess, comprising just four unitary operations, combined with the utilization of agricultural waste and commercial enzymes, presents compelling advantages. Particularly appealing to food processors aiming to enhance the circularity and sustainability of their operations while reducing reliance on external prebiotic ingredients.

Widely targeted metabolomics analysis reveals the effect of soybean hull polysaccharides on nonvolatile components of plant-based yogurt and its metabolic pattern

Soybean hull polysaccharides (SHPS) enhance the physicochemical properties of plant-based yogurt. However, their effects on the nutritional profile and biochemical mechanisms remain unclear. This study aimed to assess the impact of SHPS addition on the nonvolatile components of plant-based yogurt and its underlying mechanisms through widely targeted metabolomics analysis. The results demonstrated that the addition of SHPS (0.2 %–1.0 % w/v) enhanced the levels of free amino acids, sugars, and organic acids, with the addition of 0.6 % w/v being particularly effective in improving yogurt quality. Widely targeted metabolomics analysis revealed 278 differential metabolites between yogurt supplemented with 0.6 % SHPS (SPY) and the control sample. SHPS increased the content of various metabolites, including amino acids and derivatives, saccharides, organic acids, and flavonoids, among others. Key metabolic pathways affected by SHPS included pantothenate and CoA biosynthesis; valine, leucine, and isoleucine biosynthesis; and benzoate degradation. As the primary component of SHPS, galacturonic acid affected the metabolic products in yogurt by participating in the pentose and glucuronate interconversions and ascorbate and aldarate metabolism pathways. These findings elucidate the role of SHPS in modulating the nutritional composition of plant-based yogurt, offering valuable insights into its functional mechanisms in food processing.

Functional and physicochemical characterization of marine exopolysaccharide derived from the novel bacterium Algoriphagus sp. K5R and its application towards biomineralization of gold and silver

AbstractThe widespread use of synthetic polymers in various industries has raised worldwide concerns regarding their ecological impact and effects on human health. As a result, biopolymers have emerged as a promising alternative. Among them, exopolysaccharides (EPSs) produced by microbes from terrestrial niches have been extensively studied. However, recent reports have indicated that microbes from marine environments can also produce unique EPSs that could serve as sustainable substitutes to meet the escalating demand for biopolymers. The present study, for the first time, reports EPS production from novel marine bacterium Algoriphagus sp. K5R for sustainable application development. Interestingly, physicochemical analyses suggest that EPS K5R is a high molecular weight (1190.63 kDa) heteropolysaccharide composed of galacturonic acid, glucose and mannose. To evaluate EPS production, growth and fermentation kinetics were performed, which revealed that it was a primary metabolite having a maximum production of 4.79 ± 0.57 g L−1 with 2% (w/v) glucose. Moreover, EPS K5R exhibits exceptional functional properties, namely high water‐holding capacity (720% ± 80.29%) and oil‐holding capacity (493.33% ± 49.74% for coconut oil and 533.32% ± 17.47% for olive oil), and non‐Newtonian pseudo‐plastic behavior which render it a promising candidate for application in the cosmetics and food industries. In fact, its anti‐oxidant capabilities make it an ideal biological reducing agent for metal nanoparticle synthesis. Overall, this study highlights the potential of marine EPSs for a diverse array of industrial applications. © 2024 Society of Chemical Industry.

Utilization of Germinated Seeds as Functional Food Ingredients: Optimization of Nutrient Composition and Antioxidant Activity Evolution Based on the Germination Characteristics of Chinese Chestnut (Castanea mollissima).

The current study investigated the impact of germination duration on the functional components (vitamin C, γ-aminobutyric acid (GABA), polyphenols, flavonoids) and antioxidant activity of germs and cotyledons of the germinated Chinese chestnut (Castanea mollissima). We utilized seeds of the "Zaofeng" Chinese chestnut to germinate, and sowed the seeds in wet sand at 22 °C and 85% relative humidity. The germination rate, length, diameter, and fresh weight of the sprouts were investigated at 0, 2, 4, 6, 8, and 10 days after sowing, and the kinetic changes of amylose, amylopectin, sugar components, soluble protein, vitamin C, GABA, total phenols, flavonoids, and the DPPH and ABTS free radical scavenging activity in the germs and cotyledons were monitored, respectively. The findings revealed that the germination rate and germ biomass increased continuously during germination. The germination rate reached 90% on the 8th day after sowing. Germination reduced amylose in cotyledons from 42.3% to 34.2%, amylopectin from 42.9% to 25.8%, total sugar from 12.6% to 11.4%, and vitamin C from 1.45 mg/g to 0.77 mg/g. Meanwhile, soluble protein in the embryos rose from 0.31% to 0.60%, vitamin C from 21.1 to 29.4 mg/g, GABA from 0.49 to 1.68 mg/g, total flavonoids from 53.6 to 129.7 mg/g, and ABTS antioxidant activity from 1.52 to 3.27 μmol TE/g. The average contents of D-fructose, inositol, vitamin C, GABA, polyphenols, and flavonoids and the DPPH and ABTS antioxidant activity in germs were as high as 22.5, 6, 35, 7.5, 10, 20, and 10 and 20-fold those of cotyledons, respectively. Especially, the average content of glucose in germ was as high as 80-fold that of cotyledon. D-xylulose, D-galacturonic acid, and D-ribose were only found in germs, but not in cotyledons. Considering the germ biomass and functional components content, germs of Chinese chestnuts germinated at 22 °C for 8 days are considered the most suitable raw material for functional food products. In conclusion, controlled germination not only enhances the physicochemical and functional properties of Chinese chestnut germs but also reduces the caloric content and improves the nutritional composition of the cotyledons appropriately. Moreover, the comprehensive evaluation of compositional changes and functionality in the embryo and cotyledon of Chinese chestnuts will provide a solid foundation for subsequent functional food processing utilizing germinated Chinese chestnuts.

Polysaccharide fraction from Triplostegia glandulifera Wall and its renoprotective effect in streptozotocin-induced diabetic mice by attenuating oxidative stress

Triplostegia glandulifera Wall (T. glandulifera) is an ethnomedicine commonly used by ethnic minorities in Yunnan, China, to treat kidney disease. However, there are few reports on the renoprotective effects of this substance, and the active ingredients remain unclear. In this study, we extracted the polysaccharide fractions TGB and TGC using the water extraction-alcohol precipitation method and determined their molecular weight (Mw) and monosaccharide composition. The study investigated the protective effects of TGB and TGC fractions against diabetic nephropathy (DN) using an in vitro high glucose-induced HRMCs model and an in vivo STZ-induced diabetic mouse model. HPLC analysis revealed that TGB contained D-galacturonic acid, D-glucose, D-galactose, and D-arabinose, and had a lower Mw than TGC. In vitro, TGB showed concentration-dependent antioxidant activity and effectively reduced abnormal proliferation and while attenuating oxidative stress in HRMCs. In mice with diabetes, TGB corrected the dysregulation of glucose-lipid metabolism and alleviated oxidative stress in the kidneys. Additionally, it improved renal function and reduced renal tissue damage. The study suggests that the low Mw polysaccharides (TGB) have better activity against DN through the antioxidative stress mechanism.Graphical

A Multimodal System for Lipid A Structural Analysis from a Single Colony.

Structural elucidation of Gram-negative bacterial lipid A traditionally requires chemical extraction followed by tandem MS data in the negative ion mode. Previously, we reported FLAT and FLATn as methods to rapidly determine the structure of lipid A without chromatographic techniques. In this work, we extend the capability and effectiveness of these techniques to elucidate the chemical structure in a de novo manner by including the use of positive ion mode (FLAT+ and FLATn+) spectral approaches. Advantages of positive mode analysis of lipid A include the generation of more interpretable and informative fragmentation patterns that include the identification of diagnostic fragments, including selective dissociation of a glycosidic bond between two glucosamine units and the selective dissociation at the secondary acyl chain in 2'-N, allowing for the determination of the composition of fatty acids. As a proof of principle, we present here two previously uncharacterized structures of lipid A from Roseomonas mucosa (R. mucosa) and Moraxella canis (M. canis). In R. mucosa, we determined the lipid A structure with a nonconventional backbone of-β-1,6 linked 2,3-dideoxy-2,3-diamno-d-glucopyranose further modified with galacturonic acid in the place of typical 1-phosphate, and in M. canis, we assigned a single discrete structure using the specific fragmentation patterns of terminal phosphate groups present in lipid A. Therefore, FLATn+, in combination with FLAT and FLATn, provides a multimodal structural platform for rapid structure characterization of unusual and complex lipid A structures from a single colony.

Effect of solid-state co-fermentation on the structural characteristics and bioactivities of polysaccharides in the medicinal residues of GastrodiaGanoderma

To investigate the effect of solid-state co-fermentation on the structural characteristics and bioactivities of polysaccharides in the medicinal residues of Gastrodia Ganoderma (RGG), two kinds of polysaccharides were isolated and purified from unfermented RGG and fermented RGG, named RP and FRP, respectively. The results showed that molecular weight of FRP decreased than RP and its monosaccharide composition changed significantly. RP was mainly composed of Glucose (66.46%) and Galactose (22.83%) while the main monosaccharide components of FRP was galacturonic acid (65.67%). Fermentation caused the surface morphology of FRP to become fragmented and loose, and increased its in vitro antioxidant activity. Both RP and FRP could repair cell damage, reduce the secretion of reactive oxygen species, and protect RAW 264.7 cells from LPS-induced inflammation. Molecular docking results indicated that monosaccharide structures in FRP had stronger binding energy for inflammatory markers. This study may provide theoretical reference for the high-value utilization of Chinese herbal residues.

Synergistic pectin deconstruction is a prerequisite for mutualistic interactions between honeybee gut bacteria

The honeybee gut microbiome is crucial for degrading diverse pollen glycans. Yet it is unclear how this process shapes the interactions among bacteria. Here, we demonstrate a conditional mutualistic interaction between strains of two honeybee gut bacteria Bifidobacterium asteroides and Gilliamella apicola. When co-occurring in vitro and in vivo, Bifidobacterium provides complementary demethylation service to promote Gilliamella growth on methylated homogalacturonan, an enriched polysaccharide of pectin. In exchange, Gilliamella shares digestive products with Bifidobacterium, through which a positive interaction is established. This positive interaction vanishes when Bifidobacterium is not required on a non-methylated diet. Results from biochemical and gene expression analyses combined with model simulation further suggest that the ratio change of the two major homogalacturonan breakdown products, galacturonic acid (GalA) and di-GalA, determines the bacterial interaction. This study unravels how glycan metabolism may shape the interactions between honeybee gut bacteria.

Portulaca oleracea L. polysaccharide ameliorates ulcerative colitis by regulating the immune system and gut microbiota

This study aims to clarify the characteristics of the water-soluble polysaccharide from Portulaca oleracea L. (POL-P) and further explore its potential mechanism on ulcerative colitis (UC). POL-P was prepared and identified by gel permeation chromatography (GPC), high-performance liquid chromatography (HPLC), and scanning electron microscopy (SEM). The protective effect of POL-P was evaluated in a mouse model of UC induced by dextran sulfate sodium (DSS). Under the premise of confirming the efficacy of POL-P, we performed an integrated approach of transmission electron microscopy (TEM), fluorescence-activated cell sorting (FACS), enzyme-linked immunosorbent assay (ELISA), and 16S rRNA high-throughput sequencing to explore the effects of POL-P on the intestinal immunity and intestinal flora structure of UC mice and to further analyzed the related mechanism of POL-P in alleviating UC. ResultsThe molecular weight of POL-P was 40 kDa. POL-P contained mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, and arabinose, with a molar ratio of 1.2:13.2:33.5:1.2:3.3:32.2:15.4. The in vivo efficacy results showed that 0.8 g/kg POL-P significantly ameliorated colonic pathological damage and alleviated colon inflammation by improving the blood status and regulating the levels of IL-6, IL-17, TNF-α, and IL-10. Additionally, POL-P decreased specific immune responses, which was attributed to inhibiting the function of dendritic cells and balancing T-lymphocyte subsets. Furthermore, POL-P suppressed pathogens and ameliorated DSS-induced microbiota dysbiosis. ConclusionPOL-P functions as a novel polymer compound to alleviate UC by regulating immune and gut microbiota.

Extraction of water-soluble polysaccharides from lupin beans and their function of protein dispersion and stabilization under acidic conditions

In the current environment whereby new sources of proteins are extracted from plant material, it is also important to study the potential use of the resulting side streams. Although a number of studies have been conducted on various polysaccharides extracted from plant raw material, a polysaccharide fraction extracted from lupin bean is yet to be explored, in spite of the emerging interest in this crop as a source of food ingredients. In this work lupin soluble polysaccharide (LuPS) was obtained with a recovery as high as 46 % by extraction at pH 8, 120 °C, for 90 min. This fraction, named LuPS-8, was composed of a mostly linear pectic polysaccharide with a weight average molecular mass of 6608 kg/mol, and containing 71.0 % galactose, with minor amounts of arabinose (16.0 %), glucuronic acid 4.6 %, and galacturonic acid 4.1 %. When added to an acid milk dispersion, LuPS-8 improved its dispersibility, providing storage stability against sedimentation over a wider pH range than a HM-pectin reference, between 3.6–4.4. This research demonstrated the potential for upcycling of a side stream of lupin protein production, by the creation of value-added novel functional polysaccharide.

Differential effects of enzymatically modified Ougan (Citrus Suavissima Hort. ex Tanaka) peel pectins extracted with different methods on inhibiting the proliferation of Hela cells

Previous studies have shown that modified citrus pectin (MCP) is an anti-tumor material of food grade. In this study, two enzymatically modified Ougan (Citrus Suavissima Hort. ex Tanaka) peel pectins (EMP1 and EMP2, the ones extracted by alkali and enzymatic methods) were used to investigate their differential effects on viability and physiology of Hela cells. The results showed that EMP1 and EMP2 had 88.00 % and 81.01 % galacturonic acid, 21.31 % and 20.25 % esterification degree, 10,417 g/mol and 6416 g/mol molecular weight (Mw), 82.86 % and 50.62 % RG-I, and 8.91 % and 15.70 % HG, respectively. EMP2 had higher intensities of absorption peaks than EMP1. They were irregularly shaped, with more holes on EMP1 but more wrinkles on EMP2. Both could inhibit the growth, proliferation, migration, and invasion of HeLa cells in a concentration-dependent manner, with better efficiency in EMP2. Meanwhile, EMP2 was more efficient than EMP1 in blocking the cell cycle in S phase, resulting in apoptosis. In conclusion, the variations caused by extraction resulted in differences in anti-tumor activity of MCP and EMP2 with lower Mw and higher HG exhibited better anti-tumor effects. This study would provide an experimental basis and reference for the research and development of anti-tumor supplements from citrus pectin.

Physicochemical, structural and functional properties of pomelo peel pectin extracted by combination of pulsed electric field and cellulase hydrolysis

In this study, pectin extracted from pomelo peel was investigated using three different combination methods of pulsed electric field (PEF) and cellulase. Three action sequences were performed, including PEF treatment followed by enzymatic hydrolysis, enzymatic hydrolysis followed by PEF treatment, and enzymatic hydrolysis simultaneously treated by PEF. The three corresponding pectins were namely PEP, EPP and SP. The physiochemical, molecular structural and functional properties of the three pectins were determined. The results showed that PEP had excellent physiochemical properties, with the highest yield (12.08 %), total sugar (80.17 %) and total phenol content (38.20 %). The monosaccharide composition and FT-IR analysis indicated that the three pectins were similar. The molecular weights of PEP, EPP and SP were 51.13, 88.51 and 40.00 kDa, respectively. PEP showed the best gel properties, emulsification stability and antioxidant capacity among the three products, due to its high galacturonic acid and total phenol content, appropriate protein and low molecular weight. The mechanism of PEF-assisted cellulase hydrolysis of pomelo peel was also revealed by SEM analysis. These results suggested that PEF pretreatment was the best method, which not only improved the efficiency of enzymatic extraction, but also reduced resource waste and increased financial benefits.

Extraction of basil seed gum: Optimization and functional properties

Basil seed gum (BSG), a natural vegetable gum, was extracted by ethanol precipitation method using basil seeds as raw material. Based on the single factor experiments, Box-Behnken response surface test was performed to optimize the extraction conditions, and the physicochemical and functional properties of the extracted basil seed gum, as well as its microstructure, were analyzed in detail. The results showed that the optimal extraction conditions of basil seed gum were as follows: liquid-to-feed ratio of 62:1, temperature of 50 °C, extraction time of 29.50 min, and pH = 8.1, with yield of 11.28 %. BSG was mainly composed of total sugars (93.09 %), uronic acid (18.83 %), proteins (2.77 %), and ash (4.35 %), and its monosaccharides included D-(+)-anhydrous glucose (58.26 %), D-galactose (21.40 %), D-mannose (11.96 %), D-(+)-galacturonic acid (7.82 %), D-arabinose (0.28 %), D-(+)-xylose (0.28 %), and L-rhamnose (0.002 %). Comparative analysis of the functional properties of basil seed gum and three commercial vegetable gums (linseed gum, caraway seed gum, guar gum) showed that basil seed gum had excellent water retention properties, and its water absorption and water holding properties were much better than those of three commercial gums. Rheological characterization showed that BSG was a pseudoplastic fluid with high zero-shear viscosity. In addition, the basil seed gum powder showed an irregular flaky fibrous structure under microscope and was a semi-crystalline polymer. In view of the high aqueous absorption and retention properties of basil seed gum, it has promising applications in food, cosmetic and medical devices.

Water/oil interfacial behaviors of soy hull polysaccharide revealed by molecular dynamics simulation and particle tracking microrheology

The soy hull polysaccharide (SHP) exhibits excellent interfacial activity and holds potential as an emulsifier for emulsions. To reveal the behavior of SHP at the water/oil (W/O) interface in situ, molecular dynamics (MD) simulations and particle tracking microrheology were used in this study. The results of MD reveal that SHP molecular spontaneously move toward the interface and rhamnogalacturonan-I initiates this movement, while its galacturonic acids on it act as anchors to immobilize the SHP molecules at the W/O interface. Microrheology results suggest that SHP forms microgels at the W/O interface, with the lattices of the microgels continually undergoing dynamic changes. At low concentrations of SHP and short interfacial formation time, the network of the microgels is weak and dominated by viscous properties. However, when SHP reaches 0.75 % and the interfacial formation time is about 60 min, the microgels show perfect elasticity, which is beneficial for stabilizing emulsions.

Structural characterization and anti-inflammatory effects of polysaccharides from fruit calyx of Physalis alkekengi L. var. franchetii (Mast.) Makino

Physalis alkekengi L. (PM) is a traditional Chinese medicine with valuable nutritional and medicinal potential. Polysaccharides were considered as the important active component of calyx of P. alkekengi (PMC). In this study, four polysaccharides (PMCPs) were successfully isolated and purified by extraction, deproteination, dialysis and column chromatography. The structure characterization showed that PMCPs were mainly composed of mannose, glucosamine, ribose, rhamnose, glucose, sorbose, glucuronic acid and galacturonic acid with the molecular weights of 16.27, 71.53, 77.17 and 299.45 kDa. The FT-IR and NMR analysis suggested the presence of α and β configurations of PMCPs. PMCPs have the triple helix conformation which was determined by Congo red analysis. Moreover, the potential in vitro anti-inflammatory activity of PMCPs was investigated in lipopolysaccharide-treated RAW264.7 cells. The results indicated that PMCPs could significantly inhibit NO production at the experimental concentrations. S-PMCP-3 was found to decrease the production of pro-inflammatory cytokines including PGE2, TNF-α, IL-1β and IL-6. The findings indicated that PMCPs may be a promising natural source for addressing inflammatory damage.

Characterization of a pectin in fig fruit: Structure and anti-inflammatory activity

Fig fruit is widely accepted in warm and tropical regions due to the sweet taste and health benefits. The polysaccharides in fig fruit are responsible for the health benefits. However, information regarding polysaccharide structure remains limited. In this study, the water-soluble polysaccharides (FFP) were extracted from fig fruit with a yield of 15.3 mg/g. Anion exchange chromatography and gel permeation chromatography were used for purification. A leading polysaccharide was purified and characterized as below. The monosaccharide composition of FFP included arabinose (Ara), galactose (Gal), galacturonic acid (GalA) and rhamnose (Rha). The glycosidic linkages were revealed to be L-Ara-(1→, →5)-L-Ara-(1→, →2,4)-L-Rha-(1→, →2)-L-Rha-(1→, →4)-D-Gal-(1→ and D-Gal-(1 → . Nuclear magnetic resonnance (NMR) spectra revealed that FFP had →4)-α-D-GalpA-(1 → 2)-α-L-Rhap-(1→ as backbone. The side chains included Galp-β-D-(1 → 4)-Galp-β-D-(1 → 4)-Galp-β-D-(1 → 4)-Galp-β-D-(1→ and α-L-Araf-(1 → 5)-α-L-Araf-(1 → . They were linked to C-4 of Rhap. FFP inhibited the production of NO, IL-6 and IL-1β levels induced by LPS. IL-6 and IL-1β levels were returned to normal. These information are helpful to understand this functional fruit.

Chemical characterization and pharmacological properties of polysaccharides from Allium roseum leaves: In vitro and in vivo assays

Allium roseum is amongst the most important wild medicinal plants. It is known for its diverse biological properties, including antioxidant, antibacterial and antidiabetic activities. In this work, the polysaccharides (PARLs) were ultrasonically extracted from Allium roesum leaves then purified and analyzed by several techniques. Chemical composition and GC–MS analysis showed that the obtained polysaccharides were composed mainly of glucose (40.20 %), mannose (25.30 %), fructose (10.60 %) and galacturonic acid (15.11 %). Moreover, PARLs exhibited a potent antioxidant effect with higher capacities up to 69.61 % and 71.72 % for DPPH and ABTS free radicals, respectively. Furthermore, PARLs significantly modulated inflammatory response by reducing TNF-α, IL-6, and IL-8 pro-inflammatory mediators and promoting the anti-inflammatory IL-10 mediator in LPS stimulated THP-1 derived macrophages. The in-vivo tests proved that the extract was able to decrease carrageenan-induced rat paw swelling by around 68.15 % after 4 h of treatment. PARLs, significantly reduced the growth of U87 (glioblastoma) and IGROV-1 cancer cells with IC50 values of about 4.27 and 7.89 mg/mL respectively. This research clearly shows that Allium roseum polysaccharides can be used as natural antioxidants with anti-inflammatory and anticancer properties.

Immunomodulatory, Antioxidant, and Potential Anticancer Activity of the Polysaccharides of the Fungus Fomitiporia chilensis.

Fomitiporia species have aroused the interest of numerous investigations that reveal their biological activity and medicinal potential. The present investigation shows the antioxidant, anticancer, and immunomodulatory activity of acidic polysaccharides obtained from the fungus Fomitiporia chilensis. The acidic polysaccharides were obtained for acidic precipitation with 2% O-N-cetylpyridinium bromide. Chemical analysis was performed using FT-IR and GC-MS methods. The antioxidant capacity of acidic polysaccharides from F. chilensis was evaluated by scavenging free radicals with an ABTS assay. Macrophage proliferation and cytokine production assays were used to determine the immunomodulatory capacity of the polysaccharides. Anti-tumor and cytotoxicity activity was evaluated with an MTT assay in the U-937, HTC-116, and HGF-1 cell lines. The effect of polysaccharides on the cell cycle of the HCT-116 cell line was determined for flow cytometry. Fourier Transform-infrared characterization revealed characteristic absorption peaks for polysaccharides, whereas the GC-MS analysis detected three peaks corresponding to D-galactose, galacturonic acid, and D-glucose. The secreted TNF-α concentration was increased when the cell was treated with 2 mg mL-1 polysaccharides, whereas the IL-6 concentration was increased with all of the evaluated polysaccharide concentrations. A cell cycle analysis of HTC-116 treated with polysaccharides evidenced that the acidic polysaccharides from F. chilensis induce an increase in the G0/G1 cell cycle phase, increasing the apoptotic cell percentage. Results from a proteomic analysis suggest that some of the molecular mechanisms involved in their antioxidant and cellular detoxifying effects and justify their traditional use in heart diseases. Proteomic data are available through ProteomeXchange under identifier PXD048361. The study on acidic polysaccharides from F. chilensis has unveiled their diverse biological activities, including antioxidant, anticancer, and immunomodulatory effects. These findings underscore the promising therapeutic applications of acidic polysaccharides from F. chilensis, warranting further pharmaceutical and medicinal research exploration.

Ultrasonic-assisted extraction, analysis and properties of purple mangosteen scarfskin polysaccharide and its acetylated derivative

Purple mangosteen scarfskin polysaccharide has many important physiological functions, but its preparation method, structure, and function need further exploration. A polysaccharide was obtained from mangosteen scarfskin by ultrasonic-assisted extraction and purified. On this basis, its structure and physicochemical properties were investigated. The Congo red experiment was used to determine whether it has a triple helix conformation. The structure of purple mangosteen scarfskin polysaccharide was further analyzed by infrared spectroscopy and nuclear magnetic analysis. The antioxidant activities of the above three polysaccharides were studied by related experiments. It was found that the monosaccharide composition of purple mangosteen scarfskin polysaccharide mainly contained a large amount of arabinose, a small amount of rhamnoose and a very small amount of galacturonic acid, and its core main chain was composed of 1,4-α-arabinose. It did not have this spatial configuration. After the acetylation of purple mangosteen scarfskin polysaccharide, the acetylated derivative with a degree of substitution of 0.33 was obtained. It was found that they had certain scavenging and inhibiting effects on hydroxyl radicals and lipid peroxidation, and their activities were related to the concentration of polysaccharides. Meanwhile, the antioxidant activity of the polysaccharide was significantly enhanced after the modified treatment of acetylation, which indicated that chemical modification could effectively improve some activities of polysaccharide. The above studies provided some reference value for the further research and development of purple mangosteen scarfskin polysaccharide.

Polysaccharides, the active component of Dendrobiumofficinale flower, ameliorates chronic pharyngitis in rats via TLR4/NF-κb pathway regulation

Ethnopharmacological relevanceChronic pharyngitis persistently afflicts a large population and accounts for approximately one-third of otolaryngology patients. Currently, the treatment of CP remains controversial because of the poor outcomes. Dendrobium officinale is a well-used “Yin-nourishing” traditional Chinese medicinal and edible herb used for thousands of years in China. The flowers of D. officinale are often used in folk of China to make tea for voice protection on and throat clearing. Aim of the studyThis study was to evaluate beneficial effects of polysaccharides from D. officinale flower (DOFP) on CP and its potential mechanisms. MethodsChemical characterization of DOFP, including polysaccharide content and monosaccharide composition, structural characterization using Fourier transform infrared spectroscopy were performed. A CP model was established in rats by administering a mixture of Chinese Baijiu and chili pepper liquid, combined with low-concentration ammonia spraying. The general states, amount of oral secretion, and apparent state of the pharynx of CP rats were observed during the period of DOFP administration. Furthermore, hemorheological parameters were measured using an automatic hematology analyzer. The levels of tumor necrosis factor-α (TNF-α), interleukin 1β (1L-1β), lipopolysaccharide (LPS), and D-lactate (D-LA) in the serum were measured by enzyme-linked immunosorbent assay. Morphological changes in the pharynx and colon were observed by hematoxylin-eosin staining. The expression of nuclear factor-κB p65 (NF-κB p65), p-NF-κB p65, cyclooxygenase-2 (COX-2), interleukin 1β（IL-1β）and mucin 5AC (MUC5AC) in the pharynx,Claudin-1, Occludin, and interleukin 6 (IL-6) in the colon was detected by immunohistochemistry and Western Blot. The mRNA expression of TLR4, COX-2, and IL-1β in the pharynx were determined using reverse transcription quantitative real-time PCR. ResultsIn this study, DOFP with a total polysaccharide content of 71.44% and a composition of D-mannose, galacturonic acid, glucose, galactose, and arabinose in a molar ratio of 3.95:2.19:1.00:0.74:1.30, was isolated from the flowers of D. officinale. DOFP improved the general state and exhibited significant effects on reducing oral secretion, alleviating pharyngeal injury, suppressing inflammatory cell infiltration in the pharynx, decreasing the serum levels of TNF-α and IL-1β, and reducing the number of white blood cells and lymphocytes in the model rats. Moreover, the expressions of TLR4, p-NF-κB p65, COX-2, IL-1β and MUC5AC in the pharynx of model rats were obviously inhibited. In addition, the levels of LPS, D-LA in the serum and the protein expression of IL-6 in the colon were downregulated when the protein expression of Occludin and Claudin-1 in the colon were upregulated. ConclusionsDOFP exerts significant ameliorating effects on CP and it likely acts by inhibiting LPS/TLR4-associated inflammatory mediator activation and reducing excessive secretion of mucus by repairing the intestinal barrier in CP rats.