Characterization of a novel polysaccharide from the leaves of Moringa oleifera and its immunostimulatory activity

Identification of an arabinogalactan with special structure from Moringa Oleifera Lam. leaf and exploration of its immunomodulatory activity

Arabinogalactan exhibits many biological activities, which is the candidate for functional food ingredients. However, there is limited research on the arabinogalactan from Moringa Oleifera leaf, and its structure needs to be more accurately characterized. This study investigated structural characteristics and immunomodulatory activity of a high-purity polysaccharide from Moringa oleifera leaf (i.e. MOLP-PE) to further explore arabinogalactan from Moringa Oleifera Lam. leaf and its potential application area. The results showed that MOLP-PE was a unique type II arabinogalactan: the main chain consisted of → 3, 4)-α-D-Galp-(1→, →3)-β-D-Galp-(1→ and →2, 4)-β-D-Rhap-(1→, with branches at the C-4 position of →3, 4)-α-D-Galp-(1→ and →2, 4)-β-D-Rhap-(1→, consisting of →5)-α-L-Araf-(1→, →3)-α-L-Araf-(1→, →6)-β-D-Galp-(1→ and →4)-β-D-GalpA-(1→. Compared with arabinogalactan from larch, galactan and arabinan, MOLP-PE exhibited stronger ability in stimulating proliferation, phagocytosis and cytokines release of macrophages and bound with Toll-like receptor 4 closer via more binding sites, which might be due to its higher contents of 1,3-linked-Galp and 1,5-linked-Araf. These findings elucidated that MOLP-PE, as type II arabinogalactan with a unique structure, could be exploited as an immunomodulatory food ingredient.

Immunomodulatory, antioxidant, and growth-promoting activities of dietary fermented Moringa oleifera in Nile tilapia (Oreochromus niloticus) with in-vivo protection against Aeromonas hydrophila

BACKGROUND

Moringa oleifera, a well-known medicinal plant, has been used in aquafeed as a dietary supplement. Based on previous studies, insufficient research is available on the dietary supplementation of Nile tilapia with M. oleifera leaf and seed mixtures, specifically the fermented form. Therefore, this study aimed to investigate the efficacy of fermented (FMO) versus non-fermented M. oleifera (MO) leaf and seed mixtures on immunological parameters, antioxidant activity, growth performance, and resistance to A. hydrophila infection after a 30-day feeding trial on Nile tilapia.

METHODS

A total of 180 fingerlings were randomly divided into four groups in addition to the control group (36 fish each, in triplicate). Fish in the tested groups were fed on basal diet supplemented with MO5%, MO10%, FMO5%, and FMO10%, while those in control were fed on basal diet only. After the feeding trial, fish were challenged with A. hydrophila. The immunomodulatory activity of M. oleifera was evaluated in terms of phagocytic and lysozyme activities, immune-related cytokines and IgM gene expression. Antioxidants, and growth-promoting activities were also assessed.

RESULTS

The results revealed that fish supplemented FMO markedly in FMO10% group followed by FMO5%, exhibited significant (P < 0.05) improvement in the tested immunological, hepatic antioxidants, and growth performance parameters. Furthermore, the highest survival rate post-challenge with mild clinical symptoms, and the lowest A. hydrophila bacterial count were reported in these groups. Meanwhile, MO10%-supplementation exhibited the opposite trend.

CONCLUSIONS

The study' conclusion suggests that fermented M. oleifera leaf and seed mixture is a promising growth-promoting and immunostimulatory feed-additive candidate for Nile tilapia and could reduce the losses caused by A. hydrophila infection.

The properties and mechanism of action of plant immunomodulators in regulation of immune response - A narrative review focusing on Curcuma longa L., Panax ginseng C. A. Meyer and Moringa oleifera Lam

Herbal treatments have been utilized for millennia to cure a variety of ailments. There are over 20, 000 herbal remedies available to treat cancer and other disease in humans. In Ayurveda, traditional plants having revitalizing and nourishing characteristics are known as "Rasayanas." They have anti-inflammatory, anticancer, anti-microbicidal, antiviral, and immunomodulatory effects on the immune system. Immunomodulation is a mechanism through which the body stimulates, suppresses, or boosts the immune system to maintain homeostasis. Plant-derived immunomodulators are typically phytocompounds, including carbohydrates, phenolics, lipids, alkaloids, terpenoids, organosulfur, and nitrogen-containing chemicals. Immunomodulation activity of phytocompounds from traditional plants is primarily mediated through macrophage activation, phagocytosis stimulation, peritoneal macrophage stimulation, lymphoid cell stimulation, and suppression or enhancement of specific and non-specific cellular immune systems via numerous signalling pathways. Despite extensive research, the precise mechanism of immunomodulation of most traditional plants has not yet been fully elucidated, justifying the need for further experimentation. Therefore, this review describes the immunomodulatory agents from traditional plants such as Curcuma longa L., Panax ginseng C.A. Meyer, and Moringa oleifera Lam, further highlighting the common molecular targets and immunomodulatory mechanism involved in eradicating diseases.

Physicochemical characterization, antioxidative and immunoregulatory activity of polysaccharides from the flower of Hylocereus undatus (Haw.) Britton et Rose

The flower of Hylocereus undatus (Haw.) Britton et Rose is widely recognized as a kind of medicine-food homologous resource due to its high nutritional value. However, there is a lack of in-depth studies on the purification, structure, antioxidative and immunoregulatory activities of polysaccharides from H. undatus flowers (FHRP). The objective of this study was to investigate the primary structure, antioxidative and immunoregulatory activities of the polysaccharides extracted from Hylocereus undatus flower using water extraction and chromatogram purification. Three polysaccharide fractions named FHRP-1, FHRP-2 and FHRP-3 were obtained. The results showed that FHRP-1, FHRP-2 and FHRP-3 (200-800 μg/mL) treatment for 24 h significantly increased the activities of superoxide dismutase (SOD) and catalase (CAT), and reduced the malondialdehyde (MDA) production in RAW 246.7 cells under H2O2-induced oxidative stress. Additionally, all three fractions exhibited immunoregulatory activities by enhancing the pinocytosis of RAW 264.7 cells and promoting the production of nitric oxide (NO), interleukin 6 (IL-6), and tumor necrosis factor α (TNF-α). Among three polysaccharide fractions, FHRP-3 exhibited the most promising antioxidative and immunoregulatory properties, which was attributed to its higher content of uronic acid, moderate molecular weight, and triple-helix conformation. These findings provide preliminary insights into the primary structural information and biological activities of FHRP.

Moringa induces its beneficial effect via hormesis

Moringa oleifera, a traditional Indian herb, is widely known for its capacity to induce antioxidant, anti-inflammatory and other chemoprotective effects in a broad range of biomedical models. These perspectives have led to an extensive number of studies using various moringa extracts to evaluate its capacity to protect biological systems from oxidative stress and to explore whether it could be used to slow the onset of numerous age-related conditions and diseases. Moringa extracts have also been applied to prevent damage to plants from oxidative and saline stresses, following hormetic dose–response patterns. The present paper provides the first integrated and mechanistically based assessment showing that moringa extracts commonly induce hormetic dose responses and that many, perhaps most, of the beneficial effects of moringa are due to its capacity to act as an hormetic agent.

Structural characterization of polysaccharide fractions in areca (Areca catechu L.) inflorescence and study of its immunological enhancement activity in vitro and in vivo

To obtain the structure-function relationship of the polysaccharides derived from areca (Areca catechu L.) inflorescences in the aspect of its immunomodulatory ability, the plant-based polysaccharide was isolated and purified on column chromatography. The purity, primary structure and immune activity of four polysaccharide fractions (AFP, AFP1, AFP2 and AFP2a) were characterized comprehensively. The main chain of AFP2a was confirmed to be composed of → 3,6)-β-D-Galp-(1→, with branch chains linked to the O-3 position on the main chain. The immunomodulatory activity of the polysaccharides was evaluated using the RAW264.7 cells and immunosuppression mice model. It was observed that AFP2a enabled greater NO release (49.72 μmol/L) than other fractions, significantly promoted the phagocytic activity of macrophages, and improved splenocyte proliferation and T lymphocyte phenotype in mice. The present results may shine a light on a new research direction in immunoenhancers and provide a theoretical foundation for the development and application of areca inflorescence.

Innovative Materials with Possible Applications in the Wound Dressings Field: Alginate-Based Films with Moringa oleifera Extract

For a long time, biopolymers have proven their effectiveness in the development of materials with various applications, lately those intended for the biomedical and pharmaceutical industries, due to their high biocompatibility and non-toxic, non-allergenic, and non-immunogenic nature. The ability to incorporate various active substances in this matrix has yielded materials with characteristics that are far superior to those of classic, conventional ones. The beneficial effects of consuming Moringa oleifera have promoted the use of this plant, from Ayurvedic to classical medicine. The addition of such compounds in the materials intended for the treatment of surface wounds may represent the future of the development of innovative dressings. This study followed the development of materials based on sodium alginate and moringa powder or essential oil for use as dressings, pads, or sheets. Thus, three materials with the addition of 10-30% moringa powder and three materials with the addition of 10-30% essential oil were obtained. The data were compared with those of the control sample, with sodium alginate and plasticizer. The microtopography indicated that the materials have a homogeneous matrix that allows them to incorporate and maintain natural compounds with prolonged release. For example, the sample with 30% moringa essential oil kept its initial shape and did not disintegrate, although the swelling ratio value reached 4800% after 20 min. After testing the mechanical properties, the same sample had the best tensile strength (TS = 0.248 MPa) and elongation (31.41%), which is important for the flexibility of the dressing. The same sample exhibited a very high antioxidant capacity (60.78% inhibition). The materials obtained with moringa powder added presented good values of physical and mechanical properties, which supports their use as wound dressings for short-term application and the release of embedded compounds. According to the obtained results, all the biopolymeric materials with moringa added can be used as dressings for different wound types.

Moringa oleifera leaf polysaccharides exert anti-lung cancer effects upon targeting TLR4 to reverse the tumor-associated macrophage phenotype and promote T-cell infiltration

Tumor-associated macrophages (TAMs) participate in tumorigenesis, growth, invasion as well as metastasis by facilitating an immunosuppressive tumor microenvironment. Reversing the pro-tumoral M2 phenotype of TAMs has become a hot spot in advancing cancer immunotherapy. In the current study, the content of Moringa oleifera leaf polysaccharides (MOLP) was determined and characterized, along with the anti-cancer mechanism of MOLP studied in a Lewis lung cancer (LLC) tumor-bearing mouse model and bone marrow-derived macrophages. The monosaccharide composition and gel permeation chromatography analyses show that MOLP are mainly composed of galactose, glucose, and arabinose, with approximately 17.35 kDa average molecular weight (Mw). In vivo studies demonstrate that MOLP convert TAMs from the immunosuppressive M2 phenotype to the antitumor M1 phenotype, thus inducing CXCL9 and CXCL10 expression and increasing T-cell infiltration in the tumor. Furthermore, macrophage depletion and T cell suppression demonstrated that the tumor suppressive effect of MOLP was reliant on reprogramming macrophage polarization and T cell infiltration. In vitro studies revealed that MOLP could induce the phenotypic switch from M2 macrophages to M1 by targeting TLR4. The current study highlights that MOLP are promising anticancer plant-derived polysaccharides with potential in modulating the immune microenvironment and have a bright application prospect in the immunotherapy of lung cancer.

The effect of structure and preparation method on the bioactivity of polysaccharides from plants and fungi

Polysaccharides are not only the main components in the cell walls of plants and fungi, but also a structure that supports and protects cells. In the process of obtaining polysaccharides from raw materials containing cell walls, the polysaccharides on the cell walls are the products and also a factor that affects the extraction rate. Polysaccharides derived from plants and fungi have mild characteristics and exhibit various biological activities. The biological activity of polysaccharides is related to their chemical structure. This review summarizes the effects of the physicochemical properties and structure of polysaccharides, from cell walls in raw materials, that have an impact on their biological activities, including molecular weight, monosaccharide composition, chain structure, and uronic acid content. Also, the structure of certain natural polysaccharides limits their biological activity. Chemical modification and degradation of these structures can enhance the pharmacological properties of natural polysaccharides to a certain extent. At the same time, the processing method affects the structure and yield of polysaccharides on the cell wall and in the cell. The extraction and purification methods are summarized, and the effects of preparation methods on the structure and physiological effects of polysaccharides from plants and fungi are discussed.

Moringa oleifera leaf polysaccharide alleviates experimental colitis by inhibiting inflammation and maintaining intestinal barrier

The characteristic of ulcerative colitis (UC) is extensive colonic mucosal inflammation. Moringa oleifera (M. oleifera) is a medicine food homology plant, and the polysaccharide from M. oleifera leaves (MOLP) exhibits antioxidant and anti-inflammatory activity. The aim of this study to investigate the potential effect of MOLP on UC in a mouse model as well as the underlying mechanism. Dextran sulfate sodium (DSS) 4% in drinking water was given for 7 days to mice with UC, at the same time, MOLP (25, 50, and 100 mg/kg/day) was intragastric administered once daily during the experiment. Structural analysis revealed that MOLP had an average molecular weight (Mw) of 182,989 kDa and consisted of fucose, arabinose, rhamnose, galactose, glucose, xylose, mannose, galactose uronic acid, glucuronic acid, glucose uronic acid and mannose uronic acid, with a percentage ratio of 1.64, 18.81, 12.04, 25.90, 17.57, 12.01, 3.51, 5.28, 0.55, 1.27, and 1.43%, respectively. In addition, the features of MOLP were identified by Fourier-transform infrared (FT-IR) and spectra, X-ray diffraction (XRD). The results showed that MOLP exhibited protective efficacy against UC by alleviating colonic pathological alterations, decreasing goblet cells, crypt destruction, and infiltration of inflammatory cells caused by DSS. Furthermore, MOLP notably repressed the loss of zonula occludens-1 (ZO-1) and occludin proteins in mucosal layer, as well as up-regulating the mRNA expression of interleukin-10 (IL-10) and peroxisome proliferator-activated receptor-γ (PPAR-γ), whereas down-regulating the activation of Toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), nuclear factor-kappa B (NF-κB) signaling pathway and the production of pro-inflammatory cytokines. Therefore, these results will help understand the protective action procedure of MOLP against UC, thereby providing significance for the development of MOLP.

Ultrasonic-Cellulase Synergistic Extraction of Crude Polysaccharides from Moringa oleifera Leaves and Alleviation of Insulin Resistance in HepG2 Cells

Moringa oleifera leaves (MOL) are a new food resource, rich in functional factors. MOL polysaccharides are important active macromolecules within MOL. However, there are problems, such as low extraction rates and lack of evidence for functional activity. Therefore, in this experiment, single-factor experiments were carried out using MOL powder as the raw material, and the Plackett-Burman test was used to screen the significantly influential test factors. The extraction process of MOL polysaccharide was optimized by response surface methodology. The insulin resistance alleviating activity of MOLP polysaccharides was initially explored. The results showed that the extraction of Moringa oleifera leaves crude polysaccharides (MOLP) by ultrasonic assisted cellulase enzymatic digestion was (17.03 ± 1.03)%, and the obtained MOLP was a crude polysaccharide with an average molecular weight (Mw) of 279.48 kDa, consisting of fucose, rhamnose, arabinose, galactose, glucose, xylose, mannose, galacturonic acid, and glucuronic acid. MOLP had an IC50 value of 8.02 mg/mL for α-glucosidase and scavenging activity against free radicals such as ABTS, DPPH, hydroxyl radicals, and superoxide anion with an IC50 value of 0.21 mg/mL 0.31 mg/mL 0.97 mg/mL 0.49 mg/mL. At the same time, MOLP significantly enhanced the glucose consumption, glycogen synthesis, CAT, SOD, GSH-Px activity, and reduced the MDA and ROS content in high glucose-induced insulin-resistant HepG2 (IR-HepG2) cells. This experiment improved the extraction rate of MOLP and demonstrated that MOLP has antioxidant activity and α-glucosidase inhibitory activity, which can alleviate the insulin resistance of high glucose-induced HepG2 cells. It provides partial data support for the possible hypoglycemic effect of MOLP by alleviating oxidative stress, and also provides new ideas for the in-depth study of basic research and industrial application of MOLP.

Comprehensive analysis of microbiome, metabolome and transcriptome revealed the mechanisms of Moringa oleifera polysaccharide on preventing ulcerative colitis

This study aimed to investigate the protective effect of Moringa oleifera polysaccharide (MOP) on ulcerative colitis (UC) and explore its mechanism through the combined analysis of microbiome, metabolome and transcriptome. A UC model in mice was established using dextran sulphate sodium. After a 21-day experiment, results showed that MOP could inhibit the weight loss and disease activity index in UC mice. The intervention of MOP decreased the expression of inflammatory cytokines and promoted the secretion of tight junctions. MOP could promote the growth of probiotics such as Lachnospiraceae_NK4A136, Intestinimonas and Bifidobacterium in UC mice. The results of metabolomic and transcriptomic analysis indicated that MOP could regulated the metabolism of polyunsaturated fatty acid and PPAR, TLR and TNF signalling pathways might play important roles in the process. Altogether, MOP could be used as a functional food to prevent UC.

Recent developments in Moringa oleifera Lam. polysaccharides: A review of the relationship between extraction methods, structural characteristics and functional activities

Moringa oleifera Lam. (M. oleifera Lam) is a perennial tropical deciduous tree that belongs to the Moringaceae family. Polysaccharides are one of the major bioactive compounds in M. oleifera Lam and show immunomodulatory, anticancer, antioxidant, intestinal health protection and antidiabetic activities. At present, the structure and functional activities of M. oleifera Lam polysaccharides (MOPs) have been widespread, but the research data are relatively scattered. Moreover, the relationship between the structure and biological activities of MOPs has not been summarized. In this review, the current research on the extraction, purification, structural characteristics and biological activities of polysaccharides from different sources of M. oleifera Lam were summarized, and the structural characteristics of purified polysaccharides were focused on this review. Meanwhile, the biological activities of MOPs were introduced, and some molecular mechanisms were listed. In addition, the relationship between the structure and biological activities of MOPs was discussed. Furthermore, new perspectives and some future research of M. oleifera Lam polysaccharides were proposed in this review.

Structural characterization and immunoregulatory activity of a novel acidic polysaccharide from Scapharca subcrenata

A novel acidic polysaccharide named SSPA50-1 was isolated from Scapharca subcrenata using a simulated gastric fluid extraction method. SSPA50-1 is a heteropolysaccharide with an average molecular weight of 44.7 kDa that is composed of galacturonic acid, glucose, galactose, mannose, ribose, rhamnose, fucose, xylose and arabinose at a molar ratio of 1.00:5.40:9.04:3.10:1.59:4.01:2.10:2.21:2.28. The structural characterization based on the methylation and 1D/2D NMR analyses indicated that SSPA50-1 is composed of →3)-β-L-Rhap-(1→, →3)-β-L-2-O-Me-Fucp-(1→, →2)-α-D-Xylp-(1→, →5)-α-L-Araf-(1→, →3)-β-D-Galp-(1→, →6)-α-D-Glcp-(1→, →3,4)-β-D-Manp-(1→, →3,4)-β-D-Galp-(1→, β-D-Ribf-(1→, α-D-Glcp-(1→, and α-D-GalAp6Me-(1→. Furthermore, SSPA50-1 possessed potent immunoregulatory activity by enhancing the phagocytosis and NO, iNOS, TNF-α and IL-6 secretion capacity of RAW264.7 cells. Otherwise, SSPA50-1 significantly promoted the proliferation of splenic lymphocytes and RAW264.7 macrophages. These results indicated that SSPA50-1 could be developed as a potential ingredient for immunostimulatory agents.

The hypoglycemic and hypolipemic potentials of Moringa oleifera leaf polysaccharide and polysaccharide-flavonoid complex

In this study, Moringa oleifera leaf (MOL) flavonoids (MOLF) with strong α-glucosidase inhibitory activity and MOL polysaccharides (MOLP) with strong cholic acid-binding capacity were efficiently prepared by two-stage extraction method and mixed in a certain proportion for development of MOL highly-processed products with hypoglycemic and hypolipemic potentials. Quercetin-3-O-glucoside (6.86%) and kaempferol-3-O-glucoside (4.02%) were identified as the main components of MOLF. MOLP constructed by galactose, arabinose, rhamnose and galacturonic acid possessed the strongest effects on delaying glucose diffusion and dialysis, delaying starch digestion, binding bile acids and inhibiting cholesterol micelle solubility, being the best MOL highly-processed products for regulating carbohydrate and lipid digestion and absorption. MOLF and MOLP had synergistic effect on delaying glucose diffusion and dialysis, delaying starch digestion and binding bile acids, while MOLF impaired the inhibitory effect of MOLP on cholesterol micelle solubility. Compared with MOL primary-processed products including MOL powder and de-phenolic MOL powder, MOL highly-processed products including MOLP and MOLF-MOLP complex possessed stronger hypoglycemic/hypolipemic potentials.

Moringa (Moringa oleifera Lam.) polysaccharides: Extraction, characterization, bioactivities, and industrial application

Owing to numerous biological activities of different parts of Moringa oleifera Lam., various studies have been carried out to isolate and explore the activities of its various bioactive compounds including polysaccharides. Polysaccharides of M. oleifera have been reported to possess a variety of biofunctionalities including antihyperlipidemic, anti-diabetic, immunomodulatory, antihypertensive and gastrointestinal protection. In addition to bioactive polysaccharides, the gum exudated by stem of this plant is of commercial importance with wide range of applications in pharmaceutical industries. Various extraction and purification methods as well as combination of methods have been used to isolate and purify moringa polysaccharides. Studies suggest that extraction methods influence the structure of polysaccharides and thus their biological activity. This review summarizes all the available literature to provide updated information related to extraction, purification, modification, structural characterization, bioactivities and potential applications of moringa polysaccharides. This review will provide novel insights for future research and applications of moringa polysaccharides.

Isolation and identification of an arabinogalactan extracted from pistachio external hull: Assessment of immunostimulatory activity

This work studies the extraction and purification of a novel arabinogalactan from pistachio external hull. It was extracted with a simple method from pistachio hull which is considered as unexploited waste. Based on the results of sugar analysis by GC-FID, glycosidic linkage by GC-MS, NMR spectroscopy, and molecular weight by Size Exclusion Chromatography, pistachio hull water soluble polysaccharides (PHWSP) were identified as a type II arabinogalactan (AG), with characteristic terminally linked α-Araf, (α1 → 5)-Araf, (α1 → 3,5)-Araf, terminally linked β-Galp, (β1 → 6)-Galp, and (β1 → 3,6)-Galp. DEPT-135, HSQC, HMBC and COSY NMR data suggested the presence of (β1 → 3)-Galp mainly branched at O-6 with (β1 → 6)-Galp chains, α-Araf chains, and terminally linked α-Araf. These AG from pistachio external hulls showed in vitro stimulatory activity for B cells, suggesting their possible use as an immunological stimulant in nutraceutical and biomedical applications.

Recent Advances in Drumstick (Moringa oleifera) Leaves Bioactive Compounds: Composition, Health Benefits, Bioaccessibility, and Dietary Applications

Based on the availability of many nutrients, Moringa oleifera tree leaves have been widely employed as nutrients and nutraceuticals in recent years. The leaves contain a small amount of anti-nutritional factors and are abundant in innumerable bioactive compounds. Recently, in several in vivo and in vitro investigations, moringa leaves’ bioactive components and functionality are highlighted. Moringa leaves provide several health advantages, including anti-diabetic, antibacterial, anti-cancer, and anti-inflammatory properties. The high content of phytochemicals, carotenoids, and glucosinolates is responsible for the majority of these activities as reported in the literature. Furthermore, there is growing interest in using moringa as a value-added ingredient in the development of functional foods. Despite substantial study into identifying and measuring these beneficial components from moringa leaves, bioaccessibility and bioavailability studies are lacking. This review emphasizes recent scientific evidence on the dietary and bioactive profiles of moringa leaves, bioavailability, health benefits, and applications in various food products. This study highlights new scientific data on the moringa leaves containing nutrient and bioactive profiles, bioavailability, health benefits, and uses in various food items. Moringa has been extensively used as a health-promoting food additive because of its potent protection against various diseases and the widespread presence of environmental toxins. More research is needed for utilization as well as to study medicinal effects and bioaccesibility of these leaves for development of various drugs and functional foods.

Moringa oleifera polysaccharide regulates colonic microbiota and immune repertoire in C57BL/6 mice

This study investigated the effects of Moringa oleifera polysaccharide (MOP) on serum immune indices, immune organ indices, colonic microflora and immune repertoire of mice. Forty male SPF C57BL/6 mice were randomly divided into four groups and subjected to gavage of 0, 20, 40 and 60 mg/kg MOP for 28 days. Mice were sacrificed on the last day of the experiment and their thymus, spleen, blood and colon contents were collected for further detection. Our findings suggested that MOP could significantly increase the thymus index (P < 0.01) and spleen index (P < 0.05), and significantly decrease the levels of interleukin-6 and tumour necrosis factor-α in mice (P < 0.05). And MOP could regulate the proportion of colonic microflora of mice, significantly increase the abundance of Muribaculaceae and significantly decrease the abundance values of Proteobacteria, Helicobacter, Stenotrophomonas, etc (P < 0.05). In addition, MOP could regulate the usage frequencies of TRBV15 (P = 0.06) and TRBV9 (P = 0.10) on the TCRα chain and 9 V-J pairs were found to have remarkable usage frequency changes. These results implied that MOP exerted positive effects on the immune performance and intestinal health of mice.

Structural characteristics, anti-proliferative and immunomodulatory activities of a purified polysaccharide from Lactarius volemus Fr

Lactarius volemus Fr. is an edible mushroom widely consumed in China. Polysaccharide is an important nutritional component of L. volemus. This research aimed to isolate the polysaccharide from L. volemus and study its structure and bioactivities. A purified polysaccharide was identified and named as LVF-I whose primary structure was proposed considering the comprehensive results of monosaccharide composition, periodate oxidation-smith degradation, methylation analysis, FT-IR and 1D/2D NMR spectroscopy. Then the immunomodulation of LVF-I and its inhibition effect on H1299 and MCF-7 cells were investigated. Results showed that LVF-I (12,894 Da) contained fucose, mannose, glucose and galactose. It had a backbone consisting of →4)-α-D-Glcp-(1→, →6)-β-D-Manp-(1→, →6)-α-D-Galp-(1 → and →4)-β-D-Manp-(1→. And its side chains were branched at C2 of →4)-β-D-Manp-(1 → by →6)-α-D-Galp-(1→, α-D-Glcp-(1→, α-D-Galp-(1 → and α-L-Fucp-(1→. LVF-I (250-1000 μg/mL) could inhibit the proliferation of H1299 and MCF-7 cells, while enhance the proliferative response of splenocyte and the phagocytic ability of RAW264.7. Furthermore, LVF-I (250-1000 μg/mL) significantly induced the secretion of nitric oxide, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) by up-regulating their mRNA expression in macrophages. These results suggested that LVF-I had the potential to be developed as antitumor or immunomodulatory agents by inhibiting the proliferation of tumor cells and stimulating macrophages-mediated immune responses.

In vitro digestibility and prebiotic activities of a bioactive polysaccharide from Moringa oleifera leaves

In this study, the digestion and fermentation properties of a bioactive polysaccharide (MOP-2) purified from Moringa oleifera leaves and its impact on the human colonic microbiota were determined using simulated saliva-gastrointestinal digestion and human fecal fermentation models in vitro. The results showed that the simulated saliva and gastric juices had no effect on the average molecular weight (MW) of MOP-2. The MW of MOP-2 slightly decreased from 155.29 to 145.02 kDa during intestinal digestion, and the reducing sugar content increased from 0.159 to 0.234 mg/ml, indicating that MOP-2 was partially degraded during intestinal digestion. During fermentation, MOP-2 was largely used by human fecal inoculums. Notably, MOP-2 could significantly regulate the structure of the microbial community by improving the relative abundances of some beneficial gut microbiota, such as Phascolarctobacterium, Coprococcus, Roseburia, and Bacteroides. Additionally, after fermentation for 48 hr, MOP-2 could significantly improve the production of short-chain fatty acids, especially n-butyric acid, acetic acid, propionic acid, and n-valeric acid. These results suggested that MOP-2 could potentially be a gut microbiota manipulator aimed at promoting gut health. PRACTICAL APPLICATIONS: Gut microbial community is an important part of the human intestinal environment. The health of gut microbiota is closely associated with host heath. This work reported that a polysaccharide (MOP-2) purified from Moringa oleifera leaves could modulate the microbial structure by improving the relative abundances of some beneficial gut microbiota, which provided useful information for the application of MOP-2 as a prebiotic additive in food industry.

Therapeutic potential of Moringa oleifera seed polysaccharide embedded silver nanoparticles in wound healing

Wound healing is a complicated process that influences patient's life quality. Plant-based polysaccharide has recently gained interest in its use in wound dressing materials because of its biological compatibility, natural abundance, and ideal physiochemical properties. The present study reveals the potential of polysaccharide isolated from Moringa oleifera seed (MOS-PS) and its nanocomposite with silver (MOS-PS-AgNPs) as alternative materials for wound dressing. First, MOS-PS was isolated and structurally characterized by TLC, HPLC, FTIR, NMR, and GPC analyses. A green and simple method was used to synthesize AgNPs using MOS-PS as a stabilizing and reducing agent. The size, morphology, and structure of the MOS-PS-AgNPs were characterized by UV-Vis spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and zeta potential analysis. The results showed that the MOS-PS-AgNPs were spherically shaped, having no cytotoxicity toward mouse fibroblasts cells and promoting their in-vitro migration. Moreover, the MOS-PS-AgNPs displayed strong anti-microbial activity against wound infectious pathogenic bacteria. Finally, the MOS-PS-AgNPs were used for dressing animal wounds and its preliminary mechanism was studied by RT-PCR and histological analysis. The results showed that the MOS-PS-AgNPs can promote wound contraction and internal tissue growth well. Overall, our results indicated that the MOS-PS-AgNPs might be an excellent candidate for use as an optimal wound dressing material.

Moringa oleifera polysaccharides regulates caecal microbiota and small intestinal metabolic profile in C57BL/6 mice

This study investigated the effects of Moringa oleifera polysaccharides (MOP) on the serum indexes, small intestinal morphology, small intestinal metabolic profile, and caecal microbiota of mice. A new type of polysaccharides with 104,031 Da molecular weight and triple helix structure was isolated from M. oleifera leaves for in vivo experiment. Forty male SPF C57BL/6 mice aged 4 weeks were average divided into four groups randomly according to the MOP gavaged daily (0, 20, 40 and 60 mg/kg body weight MOP). After a 7-day preliminary trial period and a 28-day official trial period, the mice were slaughtered. Results showed that MOP reduced glucose, total cholesterol, and malondialdehyde. It also improved superoxide dismutase and catalase in serum (P < 0.05). For small intestinal morphology, MOP improved the villi length and crypt depth in both ileum and jejunum (P < 0.05); the ratio of villi length to crypt depth in jejunum increased (P < 0.05). MOP could cause the increase of beneficial bacteria and the decrease of harmful bacteria in caecum, further affecting the function of microbiota. In addition, MOP regulated 114 metabolites enriched in the pathway related to the synthesis and metabolism of micromolecules. In sum, MOP exerted positive effects on the serum indexes and intestinal health of mice.

Preparation, Characterization, and Immuno-Enhancing Activity of Polysaccharides from Glycyrrhiza uralensis

Glycyrrhiza uralensis is a Chinese herbal medicine with various bioactivities. Three fractions (GUPS-I, GUPS-II and GUPS-III) of G. uralensis polysaccharides (GUPS) were obtained with molecular weights of 1.06, 29.1, and 14.9 kDa, respectively. The monosaccharide compositions of GUPS-II and GUPS-III were similar, while that of GUPS-I was distinctively different. The results of scanning electron microscopy, FT-IR, and NMR suggested that GUPS-II and GUPS-III were flaky with a smooth surface and contained α- and β-glycosidic linkages, while GUPS-I was granulated and contained only α-glycosidic linkages. Moreover, GUPS-II and GUPS-III exhibited better bioactivities on the maturation and cytokine production of dendritic cells (DCs) in vitro than that of GUPS-I. An in vivo experiment showed that only GUPS-II significantly enhanced the maturation of DCs. These results indicate that GUPS-II has the potential to be used in combination with cancer immunotherapy to enhance the therapeutic effect.

Bioactive Exopolysaccharides Reveal Camellia oleifera Infected by the Fungus Exobasidium gracile Could Have a Functional Use

Camellia oleifera is an important Chinese commercial crop. Camellia oleifera can display abnormal leaves due to infection by the parasitic fungus Exobasidium gracile. Exobasidium gracile was isolated from infected leaves and used in fermentation, and exopolysaccharides EP0-1 and EP0.5-1 were purified from the fermentation broth. EP0-1 was an alkaline polysaccharide consisting mainly of the linkages α-d-Manp(1→, →2)-α-d-Manp(1→ and →6)-α-d-Manp(1→, →3)-α-d-Glcp(1→ and→4)-α-d-Glcp(1→, terminal β-d-Galf, (1→5)-β-d-Galf, and terminal β-D-GlcN(1→. EP0.5-1 was an acidic galactofuranose-containing polysaccharide. It contained the linkages of α-d-Manp(1→, →2)-α-d-Manp(1→, →6)-α-d-Manp(1→,→2, 6)-α-d-Manp(1→, →4)-α-d-Glcp(1→, and →4)-α-d-GlcUA(1→. Galactofuranose linkages were composed of terminal β-d-Galf, (1→6)-β-d-Galf and (1→2)-β-d-Galf. Exobasidium gracile exopolysaccharides displayed significant immunoregulatory activity by activating macrophages. This research indicates that infected leaves from Camellia oleifera including the exopolysaccharides produced by the parasitic fungus Exobasidium gracile by are worth further investigation as a functional product.