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Hydrolyzed guar gum has gained attention as an anti-obesity agent; however, few studies have focused on its role in amelioration of hepatic-associated metabolic processes. Here, the anti-obesity effect of low molecular weight hydrolyzed guar gum (GMLP, 1-10 kDa) on high-fat diet (HFD)-fed C57BL/6 J mice was investigated via transcriptome and metabolome in liver. GMLP reduced body weight gain and hepatic lipid accumulation dose-dependently, regulated blood lipid levels, and improved liver damage in HFD-fed mice. Integrated transcriptome and metabolome indicated that GMLP mainly altered lipid metabolism pathways (glycerophospholipid metabolism, glycerolipid metabolism, and fatty acid degradation), reduced disease biomarkers of ethyl glucuronide and neopterin, and increased levels of choline, flavin adenine dinucleotide, and pantetheine metabolites. Real-time quantitative PCR showed that GMLP downregulated key genes involved in de novo lipogenesis and triacylglycerol synthesis, while promoting fatty acid oxidation and choline synthesis. This study provides a theoretical basis for GMLP treatment in future clinical applications.

Mitophagy can selectively remove damaged mitochondria, which is critical in regulating mitochondrial homeostasis in diseases, such as cancer. Herein, we found that Aloe gel glucomannan (AGP) significantly inhibited the proliferation of colon cancer cells. RNA-seq analysis revealed that AGP upregulated autophagy, lysosome and mitochondrial fission signal pathways in colon cancer cell line CT26. Notably, AGP induced the accumulation of impaired and reactive oxygen species (ROS)-generating mitochondria, which triggered excessive mitophagy. Interestingly, the mitophagy activator enhanced AGP-induced mitophagy and cytotoxicity, whereas the mitophagy inhibitor reversed the influence of AGP. Furthermore, activation of PINK1/Parkin mitophagy pathway and transcription factor EB (TFEB) signaling was dependent on ROS overproduction. Taken together, these results indicated that AGP induced cytotoxic mitophagy through ROS-related PINK1/Parkin pathway and TFEB activation in CT26 cells. The research would provide theoretical basis for the development of AGP as a promising anticancer agent.

Macrophage activation is involved in the outcome of many diseases and is recognized as one of the best targets for disease intervention. Glucomannans had shown promising immunomodulatory potential. Herein, the activation performance of macrophages by glucomannans from different sources was thoroughly investigated. Glucomannans triggered the immune activation of macrophages, which was mainly manifested in increasing the secretion of immune effector molecules, enhancing the endocytosis and phagocytosis of macrophages, and selectively facilitating the expression of M1 phenotype. The participation of NF-κB and MAPK signaling pathways further validated the immune activation of macrophages by glucomannans. Correlation analysis indicated acetyl might be a feasible target for glucomannans to induce immune activation and the molecular weight (Mw) of glucomannans was also inseparable from the performance of immune activation. In conclusion, glucomannans showed a moderate immune activation effect on macrophages, and their difference in immune activation was closely related to the acetyl content and Mw.

In this work, effects of ascorbic acid (AH

The homeostasis between mitochondrial function and autophagy is crucial to the physiological activity of cancer cells, and its mechanism is conducive to the development of anti-tumor drugs. Here, we aimed to explore the effect and mechanism of Dendrobium officinale polysaccharide (DOP) on colon cancer cell line CT26. Our data showed that DOP significantly inhibited the proliferation of CT26 cells and elevated autophagy level. Moreover, DOP disrupted mitochondrial function through increasing reactive oxygen species (ROS) and reducing mitochondrial membrane potential (MMP), thereby impairing ATP biosynthesis, which activated AMPK/mTOR autophagy signaling. Intriguingly, the further experiments demonstrated that DOP-induced cytotoxicity, excessive autophagy and mitochondrial dysfunction were reversed after CT26 cells pretreated with antioxidant (N-acetyl-l-cysteine). Herein, these findings implied that DOP-induced mitochondrial dysfunction and cytotoxic autophagy repressed the propagation of CT26 cells via ROS-ATP-AMPK signaling, providing a new opinion for the study of antineoplastic drugs.

The fine structure in terms of backbone and branch chain features of a bioactive polysaccharide from Ganoderma atrum (PSG-1) was re-elucidated systematically using high performance anion-exchange chromatography (HPAEC), methylation and GLC-MS analysis, and 1D & 2D NMR spectroscopy. Monosaccharide composition analysis revealed that PSG-1-F0.2 fraction mainly consisted of glucose (73.8%) and glucuronic acid (15.3%), with small amount of mannose (5.7%) and galactose (5.2%). Based on methylation, multistep partial acid hydrolysis and NMR study, were proposed to substitute at the O-6 position of β-(1→3)-glucan. The small amount of mannose and galactose residues were considered to be from the other fraction in PSG which was very difficult to be separated from PSG-1-F0.2. This revised structure as an acidic β-(1→3, 1→6)-glucan is considered to be more accurate than the previous proposal of PSG-1.

β-Glucans are widely found in plants and microorganisms, which has a variety of functional activities. During production and application, interactions with other components have a great influence on the structure and functional properties of β-glucan. In this paper, interactions (including non-covalent interaction and free-radical reaction) between natural product derived β-glucan and ascorbic acid, polyphenols, bile acids/salts, metal ion or other compounds were summarized. Besides, the mechanism and influence factors of interactions between β-glucan and small-molecule compounds, and their effects on the functional properties of β-glucan were detailed. This review aims to develop an understanding and practical suggestions on interactions between β-glucan and small-molecule compounds, which is expected to provide a useful reference for processing and application.

Previous studies have suggested that water-soluble polysaccharides from fermented carrot pulp (WSP-p) have stronger anti-diabetic effects than those from un-fermented carrot pulp (WSP-n). This study aimed to improve understanding of these functional differences by comparing their molecular structures. Weight-average molecular weights of WSP-p fractions were lower than those of the corresponding WSP-n fractions. While both WSPs had similar functional groups, more fragmented particles were observed on the surface of large particles of WSP-n than WSP-p. Monosaccharide composition and methylation analysis confirmed that both WSP-p and WSP-n were pectic polysaccharides, containing rhamnogalacturonan-I-type polysaccharides with 1,4-linked α-d-galacturonic acid residues and homogalacturonan regions with 1,4-GalpA linkages. 1H and 13C NMR showed that they had similar linkage patterns. These findings suggested that probiotic fermentation of WSP mainly cleaved the linkages between repeating units, and resulted in less polydisperse molecular size distributions.

Arabinoxylan (BIF-60) was isolated from barley water-insoluble fiber (BIF) by ethanol precipitation at 60 % (v/v). BIF-60 was composed of xylose (48.5 %) and arabinose (30.3 %). Its average molecular weight was 1360 kDa. Methylation and 1D/2D NMR analysis showed that BIF-60 possessed β-(l→4)-xylan as backbone, comprised of un-substituted (1,4-linked β-Xylp, 56.9 %), mono-substituted (1,2,4-linked and 1,3,4-linked β-Xylp, 22.1 %) and di-substituted (1,2,3,4-lin4ked β-Xylp, 18.4 %) xylose units, as well as other residues (T-Araf-(1→, T-Xylp-(1→, →5)-Araf-(1→, →2)-Araf-(1→, →3)-Araf-(1→ and →4)-Glcp-(1→). BIF-60 exhibited shear-thinning behaviour, low gel stability and weak gelling ability at high concentrations. This work provides a theoretical and experimental basis for molecular structure and properties of the alkali-extracted arabinoxylan from barley kernel, which could guide further functional research and application of barley-derived arabinoxylan.

Konjac glucomannan (KGM) with a molecular weight (MW) of 823.4 kDa was partially degraded by endo-1,4-β-mannanase. Two hydrolyzed KGM fractions (KGM-M-1: 147.2 kDa and KGM-M-2: 21.5 kDa) were characterized and applied to the animal tests in comparison with the native KGM. After oral feeding to the mice, KGM-M-1 and KGM-M-2 significantly increased the levels of short chain fatty acids (SCFAs) in the colonic contents and the native KGM increased the SCFAs in the cecum. The more significant effect of the native KGM in the cecum may be attributable to its high viscosity, slowing down the movement of intestinal microflora through the cecum, while the lower MW KGM-M-1 and KGM-M-2 could move more easily through the colon to be fermented by colonic bacteria. This new finding may be useful for future research and development of low-MW KGM polysaccharides through enzyme hydrolysis for the desired gut health benefits.

Cordyceps sinensis is thought to have anti-cancer effects, but its mechanisms remain elusive. In this study, we aimed to investigate the anti-cancer effect of Cordyceps sinensis polysaccharide (CSP) on human colon cancer cell line (HCT116) and its mechanism. Results indicated that CSP significantly inhibited the proliferation of HCT116 cells, increased autophagy and apoptosis, while blocked autophagy flux and lysosome formation. Further experiments showed that CSP decreased the expression of PI3K and phosphorylation level of AKT and mTOR, increased the expression of AMPKa and phosphorylation level of ULK1. In addition, repression of CSP-induced autophagy by bafilomycin (autophagy inhibitor) enhanced apoptosis and cell death of HCT116 cells. Hence, our findings suggested that CSP inhibited the proliferation of HCT116 cells by inducing apoptosis and autophagy flux blockage, which might be achieved through PI3K-AKT-mTOR and AMPK-mTOR-ULK1 signaling. CSP may be a potential therapeutic agent for colon cancer.

The present study aimed to investigate the protective effect of cultured Cordyceps sinensis polysaccharides (CSP) on cyclophosphamide (Cy)-induced intestinal mucosal immunosuppression and microbial dysbiosis in mice. Results showed that CSP stimulated cytokines secretion (IL-12, IFN-γ, IL-4, IL-13, IL-6, IL-17, IL-10, TGF-β3, TNF-α, IL-2, IL-21) and transcription factors production (T-bet, GATA-3, RORγt, Foxp3). TLRs (TLR-2, TLR-4, TLR-6) and NF-κB pathway key proteins (p-IκB-α, NF-κB p65) were also upregulated after CSP administration. Moreover, CSP recovered SCFAs levels which decreased by Cy treatment. Furthermore, 16S rRNA sequencing of fecal samples was performed. α-diversity and β-diversity analysis revealed CSP improved microbial community diversity and modulated the overall structure of gut microbiota. Taxonomic composition analysis found that CSP increased the abundance of probiotics (Lactobacillus, Bifidobacterium, Bacteroides) and decreased pathogenic bacteria (Clostridium, Flexispira). These findings suggested the potential of CSP as a prebiotics to reduce side effects of Cy on intestinal mucosal immunity and gut microbiota.

The influence of Lactobacillus plantarum-fermentation on the structure and anti-diabetic effects of Momordica charantia polysaccharides were evaluated. High-fat diet and streptozotocin-induced type 2 diabetic rats were administrated with polysaccharides from fermented and non-fermented Momordica charantia (FP and NFP) for 4 weeks. Fermentation affected the physicochemical characterization, monosaccharide composition, molecular weight, and viscosity of Momordica charantia polysaccharides. Treatment with FP significantly ameliorated hyperglycemia, hyperinsulinemia, hyperlipidemia, and oxidative stress in diabetic rats compared with NFP. Moreover, the diversity and abundance of gut microbiota (Lactococcus laudensis and Prevotella loescheii) in diabetic rats were notably increased by treatment with FP in comparison to NFP. Meanwhile, FP-treated diabetic rats exhibited more colonic short-chain fatty acids (SCFAs) and lower pH values than that in NFP-treated rats. Overall, Lactobacillus plantarum-fermentation could enhance the anti-diabetes effects of Momordica charantia polysaccharides in rats by modifying the structure of polysaccharides to optimize gut microbiota and heighten the production of SCFAs.

In this study, polysaccharides extracted from Cyclocarya paliurus leaves were modified to obtain its three acetylated derivatives, Ac-CP1, Ac-CP2, and Ac-CP3. The physicochemical characteristics and antioxidant activities of acetylated derivatives were investigated. The results of chemical and FT-IR spectrum analysis showed differences between acetylated derivatives and native C. paliurus polysaccharide, which revealed that the acetylation were successful. Relative to unmodified polysaccharide, the protein contents of acetylated derivatives decreased, while carbohydrate values increased. The molecular weight (Mw) of acetylated derivatives were approximately 1.05-1.09×10(6)Da and were mainly composed of Ara, Gal, Glc, Man, GalA. Ac-CP1 with relatively low degree of substitution (0.13±0.01) exhibited excellent antioxidant activity in DPPH radical assay (95.21±0.89%), and also had strong chelating activity on β-carotene-linoleic acid assay (34.64±2.07%) at 0.5mg/ml. In addition, scanning electron microscope (SEM) observations suggested that acetylation could change the morphology and structure of polysaccharides from C. paliurus leaves.

Polysaccharide from seeds of Plantago asiatica L. is rich in calcium, which is important for keeping viscous and weak gelling properties of the polysaccharide. However, few studies reported effect of calcium on solution and conformational characteristics of the polysaccharide. In this study, polysaccharide was prepared from seeds of P. asiatica L. and named as PLCP. PLCP was treated with EDTA to remove calcium ion to get PLCP-E. PLCP and PLCP-E were characterized by Ubbelohde capillary viscometer, light scattering and HPSEC with refractive index, light scattering and viscometric detectors. The results showed that PLCP had much higher intrinsic viscosity, hydrodynamic radius ( R h ), radius of gyration ( R g ) and molecular weight than that of PLCP-E when measured in the same solvent. PLCP and PLCP-E were in random coil conformation in aqueous solutions according to light scattering and HPSEC measurements. HPSEC data showed PLCP-E had lower intrinsic viscosity than that of PLCP with the same molecular weight. Persistence length of L p was 2.5 nm for PLCP and 2.3 nm for PLCP-E, respectively. In conclusion, PLCP exhibited higher intrinsic viscosity and molecular weight, and stiffer conformation than that of PLCP-E, which could explain the reason of higher viscosity of PLCP.

In recent decades, microbial synthesis of polysaccharides with special functional properties has attracted increasing attention. This work reported a novel exopolysaccharide (EPS)-producing strain, Klebsiella sp. PHRC1.001 isolated from activated sludge. Physicochemical, rheological, emulsifying and toxicological properties of the obtained EPS were characterized. The EPS was mainly composed of d-glucose and l-arabinose, and was found to exist in aqueous solution in a nano-particulated form (∼50nm in diameter) with a strong tendency of aggregation. Rheological analysis showed that the EPS aqueous solution was a typical pseudoplastic fluid at higher concentration and could form weak gel upon alkaline treatment followed by neutralization. The EPS exhibited excellent emulsifying properties in stabilizing oil-in-water emulsions presumably by a Pickering mechanism owing to its nanoparticle structure. Acute toxicity test showed that 1.8g EPS per kg of body weight caused no toxic effect on mice. PHRC1.001 EPS has the potential to be a novel industrial polysaccharide.

In vitro fermentation of polysaccharide from Cyclocarya paliurus leaves by human fecal inoculums was investigated by determining the changes in contents of neutral and reducing sugar and pH value, consumption of monosaccharide and production of short-chain fatty acids (SCFAs). During fermentation, the content of neutral sugar and reducing sugar decreased as fermentation time increased except that the content of reducing sugar increased within the fermentation time 0.5h. The pH value significantly dropped from 7.2 to 6.04. Remarkably, the greatest yields and the fastest consumption of galacturonic acid were found and the yield of glucose and arabinose were relatively high. The dominant SCFAs, which were acetic acid, propionic acid and n-butyric acid, significantly increased. These results showed that polysaccharide was partly fermented, glycosidic bonds with galacturonic acid being more susceptible to be attacked by gut bacteria and galacturonic acid might be deemed as the main producer of acetic acid.

A newly identified polysaccharide (PSG-1) has been purified from Ganoderma atrum. The study was to investigate the protective effect of PSG-1 on diabetes-induced endothelial dysfunction in rat aorta. Rats were fed a high fat diet for 8 weeks and then injected with a low dose of streptozotocin to induce type 2 diabetes. The diabetic rats were orally treated with PSG-1 for 4 weeks. It was found that administration of PSG-1 significantly reduced levels of fasting blood glucose, improved endothelium-dependent aortic relaxation, increased levels of phosphoinositide 3-kinase (PI3K), phospho-Akt (p-Akt), endothelial nitric oxide synthase (eNOS) and nitric oxide in the aorta from diabetic rats, compared to un-treated diabetics. These results suggested that the protective effects of PSG-1 against endothelial dysfunction may be related to activation of the PI3K/Akt/eNOS pathway.

In this study, ultrafiltration membrane process was employed to separate polysaccharides from Cyclocarya paliurus (Batal.) Iljinskaja (C. paliurus) to simulate industrial production. Meanwhile, the molecular weight distribution of C. paliurus polysaccharides was investigated by gel permeation chromatography. Four fractions were obtained and named as CPPS-A, CPPS-B, CPPS-C and CPPS-D, respectively. CPPS-A and CPPS-B contained approximately 69.5% and 12.7% of polysaccharides, whose molecular weight were in the range of 100-300 kDa and 120 kDa, respectively. CPPS-C was comprised of two polysaccharides with average molecular weight of 40 kDa and 15 kDa. Results showed that ultrafiltration resulted in the removal of parts of small molecule weight polysaccharides, the increase of proportion of high molecule weight ones and the obvious improvement of quality of products. Compared with ethanol precipitation and gel permeation chromatography techniques, ultrafiltration showed many advantages, and also provided theoretical support for industrial manufacturing of C. paliurus polysaccharides in separation.

The contents of 18 kinds of mineral elements in Cyclocarya paliurus polysaccharide samples were determined by ICP-AES. The limits of detection (LOD) of the method for 18 elements were in the range of 0.01-3.80 mg/kg. The average recoveries obtained by the standard addition method were found between 94.34% and 105.69% (RSD, 1.01-4.23%). The results showed that C. paliurus polysaccharides were abundant in major and trace elements which are healthy for human body. The contents of Ca, Al, Mg, K, Fe, Mn and P were very high, ranging from 274.5±10.3 to 5980.0±102.7 mg/kg, while the contents of Zn, Na, Se, Cr, Pb, Cu and As ranged from 0.9±0.1 to 37.1±4.2 mg/kg. Finally, the levels of Ni, Cd, V and Co were not detected in the samples. ICP-AES is a simple, precise and efficient method for the determination of many mineral elements in polysaccharide samples simultaneously.

A water-soluble polysaccharide from Artocarpus heterophyllus Lam. (jackfruit) pulp (JFP-Ps) was purified and its physicochemical properties were investigated. The in vitro antioxidant activities of JFP-Ps was evaluated by measuring DPPH and OH radicals scavenging activities, as well as reducing power. The results showed that JFP-Ps contained 79.12% of total sugar, 5.83% of protein, 15.65% of uronic acid, and 15 kinds of amino acids with high levels of Asp, Glu, Val, Leu and Lys. JFP-Ps was mainly composed of Rha, Ara, Gal, Glc, Xyl and GalA, with an average molecular weight of 1668kDa. FT-IR results showed the bands at the range of 1200-850cm-1 suggested the presence of carbohydrates in JFP-Ps. The results of antioxidant activities showed that JFP-Ps exhibited strong DPPH and OH radical scavenging activities, with a relatively lower reducing power, suggesting that JFP-Ps can be exploited as effective natural antioxidant applications in medical and food industries.

PLP-3 (Plantago asiatica L. polysaccharide 3) was isolated and purified from the seeds of Plantago asiatica L. Its structure characters were elucidated by monosaccharide composition analysis, partial acid hydrolysis and methylation analysis, combined with FT-IR, GC/MS, 1D and 2D NMR spectroscopy. PLP-3 was found to be arabinoxylan, containing glucuronic acid. It was consisted of β-1,4-linked Xylp backbone with short side chains attached to its O-2 (1,2,4-linked Xylp, 17.87%) or O-3 (1,3,4-linked Xylp, 24.24%) positions. The main terminal residues were T-linked Araf (8.13%), T-linked Xylp (15.58%) and T-linked GlcAp (13.22%). Small amounts of other residues were also found in PLP-3, such as 1,2,5-linked Araf, 1,2-linked Rhap, T-linked Glcp and T-linked Galp. A possible molecular structure was proposed.

The structure of a novel bioactive polysaccharide fraction from Ganoderma atrum (PSG-1) was characterised by methylation analysis and 1D/2D nuclear magnetic resonance (NMR) spectroscopy. Sugar analysis revealed that PSG-1 was composed of glucose (Glc), mannose (Man), galactose (Gal) and galacturonic acid (GalA) in molar ratio of 4.91:1:1.28:0.71. Methylation and GC–MS analysis indicated that the main linkage type was 1,3-linked-Glcp (21.08%), followed by T-Glcp (18.68%), 1,3,6-Glcp (12.97%), 1,4-Galp (12.70%), 1,6-Glcp (12.33%), 1,2-Manp (8.06%), 1,4-GalpA (6.15%), 1,4-Manp (4.55%) and 1,4,6-Glcp (3.24%). Combined the methylation analysis results with 1D (1H, 13C) and 2D (DQF-COSY, TOCSY, HSQC and HMBC) NMR spectroscopy, a preliminary structure of PSG-1 was proposed as follows: Download : Download full-size image

In this paper, polysaccharides were extracted from the seeds of Plantago asiatica L. with hot water and separated into three fractions PLP-1 (18.9%), PLP-2 (52.6%) and PLP-3 (28.5%) by Sephacryl™ S-400 HR column chomatography. The main fraction PLP-2's structure was elucidated using oxalic acid hydrolysis, partial acid hydrolysis, methylation, GC, GC–MS, 1D and 2D NMR. PLP-2 was composed of Rha, Ara, Xyl, Man, Glc and Gal, in a molar ratio of 0.05:1.00:1.90:0.05:0.06:0.10. Its uronic acid was GlcA. PLP-2 was highly branched heteroxylan which consisted of a β-1,4-linked Xyl p backbone with side chains attached to O -2 or O -3. The side chains consisted of β-T-linked Xyl p , α-T-linked Ara f , α-T-linked GlcA p , β-Xyl p -(1 → 3)-α-Ara f and α-Ara f -(1 → 3)-β-Xyl p , etc. Based on these results, the structure of PLP-2 was proposed.

The structure of a bioactive hydrophilic polysaccharide fraction from Cordyceps sinensis (CBHP) was studied using methylation analysis and 2D NMR spectroscopy. Monosaccharide composition analysis revealed that it consists mainly of glucose (95.19%) with trace amounts of mannose (0.91%) and galactose (0.61%). The results of methylation analysis indicated that α-1,4 linked Glcp is the main linkage type (65.7%), followed by t-Glcp (20.7%), 1,2,3,6-Glcp (4.1%), 1,2,4,6-Glcp (3.0%), 1,3,6-Glcp (2.0%), 1,4,6-Glcp (1.6%), and 1,2-Manp (1.9%) and 1,3-Galp (1.0%). Based on 1D and 2D NMR analysis, a preliminary structure is proposed: The backbone is composed of Glcp joined by 1 → 4 linkages and 1 → 3 linkages; the branching points are located at O-2 or O-6 of Glcp with α- terminal-d-Glcp as side chain. The trace amounts of 1,2-Manp and 1, 3-Galp linkages are probably located randomly in the side chains. A schematic structure is proposed as following: Full-size image

An advanced oxidation process, ultrasound/H2O2 oxidation was used for the decolorization of Cyclocarya paliurus (Batal.) Iljinskaja polysaccharides (CPP). The effects of main operating parameters including initial concentration of CPP solution, dosages of H2O2, temperature, pH and ultrasonic irradiation on the decolorization efficiency of CPP were investigated and the optimum operational conditions of the process were also evaluated. Furthermore, HPLC, Fourier transformed infrared (FT-IR) and NMR spectra methods were applied to analyze the components and structure changes of CPP. Results showed that ultrasound/H2O2 oxidation process represented good decolorizing ability on CPP. The optimum operational conditions were determined as follows: concentrations of the polysaccharide solution, 0.5 mg/ml; H2O2, 0.623 mM; temperature, 40 °C; pH, 9.0. Under these conditions, the decolorization efficiency was reached to 84.1%. The results of HPLC, FT-IR and NMR analysis indicated that ultrasound/H2O2 oxidation process did not result in any significant change in the structure of CPP.

Response surface methodology (RSM), based on a Box–Behnken design (BBD), was used to optimize the extraction conditions of crude polysaccharides from Herba Moslae . Three independent variables, extraction temperature, extraction time and water to solid ratio were investigated. Based on the RSM analysis, the optimal extraction conditions were determined to be at a temperature 86.9 °C, time 4.1 h and water to solid ratio 17.7:1 (mL/g). The crude polysaccharides produced under these optimal conditions contained 37.84% neutral carbohydrates, 6.14% proteins, 5.18% uronic acids, 8.1% moisture and 4.6% ash. The result of monosaccharide composition by gas chromatography (GC) showed that the crude polysaccharides consisted of eight kinds of monosaccharides: rhamnose, ribose, fucose, arabinose, xylose, mannose, glucose and galactose, with the molecular ratio of 3.72:2.45:0.92:6.00:2.76:5.09:13.53:9.58. Results of pinocytic activity and nitric oxide assays of mouse peritoneal macrophage suggested that the crude polysaccharides had potential immunomodulatory properties.

In this paper, improvement in the method for purifying glycoprotein from green tea ( Camellia sinensis ) was described; some properties and chemical compositions of tea glycoprotein (TGP) were determined by HPGPC, FT-IR, GC–MS technologies. Compared to existing methods, a more compatible method for purifying TGP was proposed. This method was faster, simpler, more effective and easier to be extended to the industrial production than the method that used in our previous work. The molecular weight of TGP was 126,513 Da using HPGPC. GC–MS analysis of TGP showed that TGP was composed of seven kinds of monosaccharides, namely ribose, rhamnose, arabinose, xylose, mannose, glucose, galactose in molar ratios of 1.71:5.88:13.70:1.99:1.00:1.84:33.75. Eighteen amino acids were identified in TGP by amino acid analysis. The FT-IR spectrum of the TGP revealed also typical characteristics of polysaccharides, protein and uronic acid.

In this study, three chemically carboxymethyl polysaccharides (CM-CPs) were derived from Cyclocarya paliurus polysaccharides. The physicochemical properties and antioxidant activity in vitro of carboxymethyl derivatives were determined. The results of degree of substitution and FT-IR analysis showed the carboxymethylation of polysaccharides were successful. Compared with unmodified polysaccharides, the contents of carbohydrate and protein were decreased while CM-CP3 with highest DS value had more uronic acid. The carboxymethyl derivatives was mainly composed of Ara, Gal, Glc, Man, GalA, with a molecular weight (Mw) of 1.03-1.08 × 10(6)Da. Compared with the native polysaccharide, the CM-CP3 with highest DS and Mw exhibited the highest antioxidant activity in β-carotene-linoleic acid assay. However, the superoxide radical and hydroxyl radical scavenging activity were decreased by CM-CPs. These results demonstrated appropriate carboxymethylation modification could enhance the potential of C. paliurus polysaccharide as oxidation inhibitor.

Main objective of this study was to investigate the detailed structural information about O-acetylated sugar residues in Dendronan(®). A water solution (2%, w/w) of Dendronan(®) was treated with endo-β-mannanase to produce oligosaccharides rich in O-acetylated sugar residues. The oligosaccharides were partly recovered by ethanol precipitation (70%, w/w). The recovered sample (designated Hydrolyzed Dendrobium officinale Polysaccharide, HDOP) had a yield of 24.7% based on the dry weight of Dendronan(®) and was highly O-acetylated. A D2O solution of HDOP (6%, w/w) generated strong signals in (1)H, (13)C, 2D (1)H-(1)H COSY, 2D (1)H-(1)H TOCSY, 2D (1)H-(1)H NOESY, 2D (1)H-(13)C HMQC, and 2D (1)H-(13)C HMBC NMR spectra. Results of NMR analyses showed that the majority of O-acetylated mannoses were mono-substituted with acetyl groups at O-2 or O-3 position. There were small amounts of mannose residues with di-O-acetyl substitution at both O-2 and O-3 positions. Minor levels of mannoses with 6-O-acetyl, 2,6-di-O-acetyl, and 3,6-di-O-acetyl substitutions were also identified. Much information about sugar residue sequence was extracted from 2D (1)H-(13)C HMBC and 2D (1)H-(1)H NOESY spectra. (1)J(C-H) coupling constants of major sugar residues were obtained. Evidences for the existence of branches or O-acetylated glucoses in HDOP were not found. The major structure of Dendronan(®) is shown as follows: [Formula: see text] M: β-D-mannopyranose; G: β-D-glucopyranose; a: O-acetyl group.

A water-soluble pectic polysaccharide (MP-A40) was isolated and purified from Mosla chinensis Maxim. cv. Jiangxiangru for the first time, with a molecular weight of 32,600Da. MP-A40 was comprised of 68.63% galacturonic acid and 13.05% neutral sugar. In addition, arabinose, galactose, rhamnose, mannose and glucose composed the neutral sugar in a relative ratio of 4.94, 3.07, 2.13, 1.62 and 1.29% of the dry weight of MP-A40, respectively. Structural characterization of MP-A40 was investigated by methylation analysis and 1D/2D NMR spectroscopy. From the results, the structure of MP-A40 was revealed as follows: 1,4-linked α-d-GalpA and 1,4-linked α-d-GalpA6Me interspersed with rare t-Araf (0.60%), t-Rhap (1.67%) and t-GalpA (10.15%). Esterification assay showed that about 32% of the carboxylic groups in GalA residues existed as methyl ester. In addition, MP-A40 could inhibit the growth of human leukemic cell line K562 and stimulate nitric oxide production from RAW 264.7 macrophages both in dose-dependent manners.

The saliva, gastric and intestinal digestion of polysaccharide from Plantago asiatica L. seeds was investigated in vitro. It was found that salivary amylase had no effect on the polysaccharide; however, the polysaccharide was influenced in later gastrointestinal digestion. A steady decrease in molecular weight (M(w)) of the polysaccharide from 1903.1±93.0 to 4.7±0.2 kDa was observed as digestion time increased. Meanwhile, the reducing ends were increased from 0.157±0.009 to 0.622±0.026 mM, indicating the decrease of M(w) may due to the breakdown of glycosidic bonds. In addition, there was no monosaccharide released throughout the whole digestion period, suggesting that the gastrointestinal digestion did not result in a production of free monosaccharide. These results may provide some information on the digestion of polysaccharide from P. asiatica L. in vitro, and may contribute to the methods of studying the digestion of other carbohydrates.

Recently, renewed interest has grown in the use of ultrasonic-assisted extraction as an alternative approach to the traditional extraction methods. In this study, this novel extraction method was used to isolate polysaccharides from Cyclocarya paliurus (Batal.) Iljinskaja, and response surface methodology (RSM) was employed to optimize the extraction conditions. The optimal conditions for the extraction of polysaccharides were determined to be the ratio of liquid to solid of 8, extraction time of 59 min and extraction temperature of 58 °C. Under these optimal conditions, the yield of polysaccharides obtained was 4.91 ± 0.11%, which was well matched with the value predicted by the model. In vitro antioxidant assays showed that the polysaccharides exhibited strong DPPH radicals (92.09% at 0.25 mg/ml) and self-oxidation of 1,2,3-phentriol (37.22% at 1 mg/ml) scavenging activities, moderate hydroxyl radicals (43.18% at 1 mg/ml) scavenging activity and lipid peroxidation inhibitory effect (31.66% at 1 mg/ml). In addition, the polysaccharides showed moderate antimicrobial activity.