Study on a novel spherical polysaccharide from Fructus Mori with good antioxidant activity.

A novel polysaccharide (MFP1P) was isolated from Fructus Mori, followed by purification via DEAE-52 cellulose and 27 % ethanol fraction. The MFP1P had the molecular weight of 56.78 kDa and the total sugar content of 93.32±0.54 %. And the MFP1P is mainly composed of glucose, galactose, galacturonic acid and mannose with molar ratio of 66.62 %, 13.94 %, 18.24 % and 1.20 %, respectively. MFP1P was mainly composed of →3)-α-D-Gal (1→, ß-D-Man-(1→ and →6)-α-D-Glc (1→ glycosidic bond and showed a spherical chain conformation with uniform distribution in solution. The MFP1P exhibited great antioxidant activity with oxygen-free radical absorption capacity (ORAC) values of 291.63±6.81 µmol TE/g and MDA IC50 of 0.289±0.022 mg/mL.

Microwave-assisted extraction of arabinan-rich pectic polysaccharides from melon peels: Optimization, purification, bioactivity, and techno-functionality.

The effects of water to solids ratio (WSR, 10-30 mL/g), power (180-540 W), and irradiation time (IT, 5-15 min) in microwave-assisted extraction (MAE) were optimized to extract polysaccharides from melon peels (PMP). The maximum extraction yield (32.81 %) was obtained under 20.94 mL/g WSR, 414.4 W power, and 12.75 min IT. The main monosaccharide composition of purified PMP with an average molecular weight of 5.71 × 104 kDa were d-galacturonic acid, arabinose, glucose, and galactose. An ascending dose-dependent antiradical and antioxidant behavior for PMP (0-5.0 mg/mL) was found. The initial foaming capacity (38.6-110.3 %) and foaming stability (5.2-65.2 %) were significantly increased as a function of PMP concentration (1.0-5.0 %), while they reduced by increasing the mixing time (p < 0.05). The highest emulsifying activity index (44.1 m2/g) and emulsifying stability (69.3 %) at 5.0 % PMPs were determined. PMP gels with FTIR-identified functional groups can be formulated in new gluten-free functional products.

Ultrafiltration isolation, structures and anti-tumor potentials of two arabinose- and galactose-rich pectins from leaves of Aralia elata.

Two novel arabinose- and galactose-rich pectic polysaccharides, AELP-B5 (Mw, 4.25 × 104 g/mol) and B6 (Mw, 1.56 × 104 g/mol), were rapidly obtained from the leaves of Aralia elata (Miq.) Seem. with anion resin and sequenced ultrafiltration membrane columns. The structural backbone and branched chains of AELP-B5 and B6 were preliminarily elucidated by mild acid hydrolysis with HILIC-ESI--MS/MS. The planar structures and spatial configurations were further identified using UPLC-QDa and GC-MS for compositions, Smith degradation and methylation analysis, FT-IR, NMR (1H/13C, DEPT, HSQC, HMBC, COSY, NOESY and TOCSY) and SEC-MALLS-RID. (1) AELP-B5 possessed →4GalA1→ as smooth regions (HG) and a repeating disaccharide moiety of →4GalA1→2Rha1→ as hairy regions (RG-I) with a 1:5 molar ratio, whereas AELP-B6 had a distinguishing 1:1 molar ratio between the HG and RG-I; (2) complex side chains were constituted of T-α-Araf, 1,3-α-Araf, 1,5-α-Araf, T-ß-Galp, 1,3-ß-Galp, 1,4-ß-Galp, 1,6-ß-Galp, 1,3,4-ß-Galp and 1,3,4,6-ß-Galp connected at C-4 of the rhamnosyl units in RG-I of AELP-B5 and B6; and (3) both possessed highly branched and compact coil conformations. The CCK-8 assay illustrated that AELP-B6 possessed higher cytotoxicity against HepG2 and HT-29 than that of AELP-B5. Surface plasmon resonance showed the binding affinity of AELP-B6 to galectin-3 (6.488 × 10-5 M) was about 10 times stronger than that of AELP-B5 (4.588 × 10-4 M). The above findings provide a molecular structure and bioactivity basis for future potential applications of AELP in the food and medical industries.

Composition, physicochemical properties, and anti-fatigue activity of water-soluble okra (Abelmoschus esculentus) stem pectins.

Okra, Abelmoschus esculentus (L.) Moench, an annual herbaceous plant, is widely distributed in tropical and subtropical regions. Water-soluble pectic hydrocolloids from okra stems (HOS) were extracted and purified using polydivinylbenzene HP-20 resins. The sugar composition of the purified HOS with an weight-average molecular weight of 178.4 ± 2.1 kDa and a polydispersity index of 1.02 ± 0.02 contained galacturonic acid (34%), galactose (31%), rhamnose (21%), arabinose (4.2%), glucuronic acid (2.5%), xylose (1.2%), and other monosaccharides (6.1%) by weight. Its favorable rheological behaviors were evident on relatively higher concentrations (20, 25, and 30 mg/mL) and moderately lower pH levels (3 and 5) of HOS. The anti-fatigue experiments in vivo demonstrated that a high dose of HOS (450 mg/kg feed) prolonged the exhaustive swimming time of mice, significantly induced an increase in blood glucose and glycogen, and decreased lactic acid and serum urea nitrogen levels. HOS digestion in vivo was fairly conducive to the improvement of energy storage capacity and renal function for physically induced fatigue, compared with the conventional herbal supplement Panax quinquefolium. Accordingly, HOS exhibits potential for reutilization of okra stem waste.

Optimization, characterization, rheological study and immune activities of polysaccharide from Sagittaria sagittifolia L.

To improve the extraction efficiency of polysaccharides from Sagittaria sagittifolia L. (SPU) by ultrasonic assisted extraction (UAE), the optimal extraction conditions were optimized as follows: extraction temperature of 85℃, extraction time of 15 min and ratio of liquid to raw material 43 mL/g, under these conditions, the yield of SPU increased by about 168 % compared with hot water extraction (HWE). After separation and purification by DEAE-52 cellulose column and Sephadex G-50 column, the pure polysaccharide fraction (SPU70-W1) was obtained, and its structure, rheology and immune activity were analyzed. The results indicated that SPU70-W1 (7.70 kDa) contained mannose, glucose and galactose in the molar ratio of 2.06:93.58:4.36 with typical pseudoplasticity fluids behavior and possessed the backbone of →2,6)-α-D-Glcp-(1→, →3,6)-α-D-Glcp-(1→, α-D-Glcp-(1→ and 6)-α-D-Glcp-(1→. In addition, SPU70-W1 exhibited remarkable immunomodulatory activity. Thus, SPU70-W1 could contribute to the food, medicine, cosmetics as a functional additive.

Isolations, characterizations and bioactivities of polysaccharides from the seeds of three species Glycyrrhiza.

In this paper, polysaccharides from the seeds of three species of genus Glycyrrhiza were extracted to investigate the physicochemical properties, structural characteristics and antioxidant activities. The polysaccharides were composed of xylose, mannose, galactose, and glucose with different molar ratio. Fourier transform infrared spectroscopy showed the presence of key functional groups of polysaccharides whereas scanning electron microscopy analysis revealed the characteristic morphology of different polysaccharides, and thermogravimetric analysis exhibited good thermal stability of all samples. The antioxidant activities of polysaccharides were evaluated in vitro. All the three polysaccharides demonstrated strong reducing power, as well as scavenging activity against DPPH, ABTS, and hydroxyl free radicals. Antioxidant assays indicated that all the polysaccharides have obvious antioxidant activities and possess a potential development and application value in food, cosmetics as well as pharmaceutical industries.

Physicochemical Characterization, Antioxidant and Immunostimulatory Activities of Sulfated Polysaccharides Extracted from Ascophyllum nodosum.

Polysaccharides from Ascophyllum nodosum (AnPS) were extracted and purified via an optimized protocol. The optimal extraction conditions were as follows: extraction time of 4.3 h, extraction temperature of 84 °C and ratio (v/w, mL/g) of extraction solvent (water) to raw material of 27. The resulting yield was 9.15 ± 0.23% of crude AnPS. Two fractions, named AnP1-1 and AnP2-1 with molecular weights of 165.92 KDa and 370.68 KDa, were separated from the crude AnPS by chromatography in DEAE Sepharose Fast Flow and Sephacryl S-300, respectively. AnP1-1 was composed of mannose, ribose, glucuronic acid, glucose and fucose, and AnP2-1 was composed of mannose, glucuronic acid, galactose and fucose. AnPS, AnP1-1 and AnP2-1 exhibited high scavenging activities against ABTS radical and superoxide radical, and showed protective effect on H2O2-induced oxidative injury in RAW264.7 cells. Furthermore, the immunostimulatory activities of AnP1-1 and AnP2-1 were evaluated by Caco-2 cells, the results showed both AnP1-1 and AnP2-1 could significantly promote the production of immune reactive molecules such as interleukin (IL)-8, IL-1ß, interferon (IFN)-γ, and tumor necrosis factor (TNF)-α. Therefore, the results suggest that AnPS and its two fractions may be explored as a potential functional food supplement.

Centrifugal partition chromatography in a biorefinery context: Separation of monosaccharides from hydrolysed sugar beet pulp.

A critical step in the bioprocessing of sustainable biomass feedstocks, such as sugar beet pulp (SBP), is the isolation of the component sugars from the hydrolysed polysaccharides. This facilitates their subsequent conversion into higher value chemicals and pharmaceutical intermediates. Separation methodologies such as centrifugal partition chromatography (CPC) offer an alternative to traditional resin-based chromatographic techniques for multicomponent sugar separations. Highly polar two-phase systems containing ethanol and aqueous ammonium sulphate are examined here for the separation of monosaccharides present in hydrolysed SBP pectin: l-rhamnose, l-arabinose, d-galactose and d-galacturonic acid. Dimethyl sulfoxide (DMSO) was selected as an effective phase system modifier improving monosaccharide separation. The best phase system identified was ethanol:DMSO:aqueous ammonium sulphate (300gL(-1)) (0.8:0.1:1.8, v:v:v) which enabled separation of the SBP monosaccharides by CPC (200mL column) in ascending mode (upper phase as mobile phase) with a mobile phase flow rate of 8mLmin(-1). A mixture containing all four monosaccharides (1.08g total sugars) in the proportions found in hydrolysed SBP was separated into three main fractions; a pure l-rhamnose fraction (>90%), a mixed l-arabinose/d-galactose fraction and a pure d-galacturonic acid fraction (>90%). The separation took less than 2h demonstrating that CPC is a promising technique for the separation of these sugars with potential for application within an integrated, whole crop biorefinery.

Studies on Unprocessed and Acid-Treated Arabinogalactan from Larch as an Inhibitor of Glycan Binding of a Plant Toxin and Biomedically Relevant Human Lectins.

The increasing evidence for the physiological significance of glycan-protein (lectin) interactions prompts considerations for respective bioactivity of plant polysaccharides. Arabinogalactan from larch, a polysaccharide with a ß1,3-linked galactose core and branches at the 6'-hydroxyl, was thus tested, together with two processed forms treated either with oxalic or trifluoroacetic acid. Hydrolysis by acid reduced the arabinose contents without backbone degradation. The three preparations were tested as an inhibitor of lectin binding in solid-phase and cell-based assays, using the toxin from Viscum album and a panel of seven human lectins (six galectins and a C-type lectin). Increasing potency correlating with the molecular contents of galactose was seen for the plant toxin. In general, relatively weak or no inhibitory capacity was detected for the three preparations, when binding of the human galectins and avian orthologues used as controls was measured. Acid-treated polysaccharides also weakly interfered with binding of the galactose-specific C-type lectin of human macrophages. Larch arabinogalactan, tested as a model, will thus most likely not impair (ga)lectin functionality physiologically.

Structural characterization and stimulating effect on osteoblast differentiation of a purified heteropolysaccharide isolated from Hedysarum polybotrys.

Radix Hedysari polysaccharides (HPS) is the principal active fraction of Radix Hedysari (RH). The information about HPS3d, the main fraction of HPS3, and its effect on bone is still unknown. In the present study, the purified HPS3d was obtained by anion-exchange column. It consisted of 94.38% polysaccharide, 3.40% protein and 13.30% uronic acid. The molecular weight was measured to be 84.6kDa. The backbone consisted of galactopyranose and galacturonopyranose, and the side chains were composed of glucopyranose, rhamnopyranose and arabinofuranose. The FT-IR and elemental analysis showed that HPS3d was the sulfated polysaccharide. HPS3d upregulated alkaline phosphatase (ALP) activity and the expression of other osteogenic marker genes in osteoblast. In addition, HPS3d increased the expression and transcriptional activity of Runt-related transcription factor 2 (Runx-2) and Osterix, the two master genes of osteoblast differentiation. These findings suggest that HPS3d stimulates osteoblast differentiation by activation of Runx-2 and Osterix.

Comparison of physicochemical properties and immunomodulatory activity of polysaccharides from fresh and dried litchi pulp.

Drying is commonly used for preservation and processing of litchi. However, its polysaccharide structure may be altered by the drying process, resulting in biological activity changes. Polysaccharides from fresh and dried litchi pulp (denoted as LPF and LPD, respectively) were isolated, investigated by GC-MS, GPC and UV/IR spectrum analysis and their antitumor and immunomodulatory activities were evaluated in vitro. LPD, the molecular weight of which was lower than that of LPF, contained more protein, uronic acid, arabinose, galactose and xylose. Compared with LPF, LPD exhibited a higher inhibitory effect on the proliferation of HepG2, Hela and A549 cells from 50-750 µg/mL. LPD was also a better stimulator of spleen lymphocyte proliferation, NK cells cytotoxicity and macrophage phagocytosis from 50-400 µg/mL. In summary, drying could change the physicochemical properties and enhance the bioactivity of polysaccharides from litchi pulp. This finding is supported by the fact that dried litchi pulps are used in Traditional Chinese Medicine.

[Applicability of a natural swelling matrix as the propellant of osmotic pump tablets].

The purpose of this study is to investigate the applicability of a natural swelling matrix derived from boat-fruited sterculia seed (SMS) as the propellant of osmotic pump tablets. The sugar components, static swelling, water uptake and viscosity of SMS were determined and compared with that of polythylene oxide (WSR-N10 and WSR-303). Both ribavirin and glipizide were used as water-soluble and water-insoluble model drugs. Then, the monolayer osmotic pump tablets of ribavirin and the bilayer osmotic pump tablets of glipizide were prepared using SMS as the osmotically active substance and propellant. SMS was mainly composed of rhamnose, arabinose, xylose and galactose and exhibited relatively high swelling ability. The area of the disintegrated matrix tablet was 20.1 times as that at initial after swelling for 600 s. SMS swelled rapidly and was fully swelled (0.5%) in aqueous solution with relative low viscosity (3.66 +/- 0.03) mPa x s at 25 degrees C. The monolayer osmotic pump tablets of ribavirin and the bilayer osmotic pump tablets of glipizide using SMS as propellant exhibited typical drug release features of osmotic pumps. In conclusion, the swelling matrix derived from boat-fruited sterculia seed, with low viscosity and high swelling, is a potential propellant in the application of osmotic pump tablets.

Human milk and related oligosaccharides as prebiotics.

Human milk oligosaccharides (HMO) are believed to have a range of biological activities beyond providing nutrition to the infant. Principal among these is that they may act as prebiotics. Prebiotics are dietary ingredients, usually oligosaccharides that provide a health benefit to the host mediated by the modulation of the human gut microbiota. While it is clear that such oligosaccharides may have potential applications in infants and adults alike, this potential is limited by the difficulties in manufacturing HMO. Consequently functional alternatives such as galacto-oligosaccharides (GOS) are under investigation. GOS are produced enzymatically from lactose for commercial use in food applications--including addition to infant formulae--as similar to breast milk oligosaccharides, they encourage a gut bacteria population that promotes health and reduces the incidence of intestinal infections. New methods for separation and concentration of complex, breast milk-like oligosaccharides from bovine milk industrial streams that contain only low amounts of these valuable oligosaccharides are providing the opportunity to investigate other viable sources of specific oligosaccharides for use as prebiotics in supplements or food products.

Pectic polysaccharide from immature onion stick (Allium cepa): structural and immunological investigation.

The structure of a water-soluble pectic polysaccharide (PS) isolated from immature onion stick (Allium cepa) was investigated using acid hydrolysis, methylation analysis, periodate oxidation study, and NMR studies ((1)H, (13)C, DQF-COSY, TOCSY, NOESY, ROESY, HSQC, and HMBC). The results of the above experiments indicated that the PS contained d-galactose, 6-O-Me-D-galactose, 3-O-acetyl-D-methyl galacturonate and D-methyl galacturonate in a molar ratio of nearly 1:1:1:1 and possesses a backbone of [→4)-α-D-GalpA6Me-(1→4)-α-D-GalpA6Me-(1→] in which one methyl galacturonate was substituted at O-3 position by an acetyl group and the neighboring methyl galacturonate being substituted at O-2 with a side chain, α-D-Galp-(1→4)-6-O-Me-ß-D-Galp-(1→. The probable structure of repeating unit of the pectic polysaccharide was established as: [formula in text] The pectic polysaccharide showed in vitro splenocyte, thymocyte as well as macrophage activations.

Structural characterisation of the polysaccharides from endemic Mongolian desert plants and their effect on the intestinal absorption of ovalbumin.

Using successive extractions with water and 0.7% aqueous ammonium oxalate, pectic polysaccharides were isolated from the following plants growing in the arid climate of Mongolia (Gobi): saxaul Haloxylon ammodendron Maxim., rhubarb Rheum nanum Sievers, Nitraria sibirica Pall., Peganum harmala L. and almond Amygdalus mongolica Maxim. The data obtained exhibited the primary synthesis of the cell wall pectic polysaccharides but not the middle lamellae water-soluble pectins in plants growing in the dry climatic zone. Both α-(1→4)-D-galacturonan and α-(1→4)-D-galacturonan, which was substituted with methyl groups, were found to be backbone of pectins. The L-arabinofuranose residues were identified as the main components of ramified regions. The pectins from almond differed from other pectins due to a high arabinose content. The data from NMR spectroscopy and methylation analyses demonstrated that pectic polysaccharides from almond included terminal, (1→5)-, (1→3)-linked and 3,5-substituted L-arabinofuranose residues and a small terminal D-galactopyranose and 2,5- and 2,3,5-substituted L-arabinofuranose residue content. The pectic polysaccharides were found to decrease the absorption of ovalbumin (OVA) in the blood from the gut lumen. The serum OVA level was lower in mice fed with OVA mixed with the pectins compared with the control group, which was administered OVA alone.

The antimutagenic effect of mistletoe lectin (Viscum album L. var. coloratum agglutinin).

A galactose- and N-acetyl-D-galactosamine-specific lectin (Viscum album L. var. coloratum agglutinin, VCA), which is known for its anticancer activity, was isolated from mistletoe. In this study, we investigated the antimutagenic potentials of VCA by using the pre-incubation method of the Ames test (Salmonella typhimurium TA98 and TA100) in the presence or absence of S9 mixture. Viscum album L. var. coloratum agglutinin was assessed for its antimutagenic properties against the mutagens 2-aminoanthracene (2AA) and furylfuramide (AF-2) for strain TA98, and sodium azide (NaN(3) ) and 2-aminoanthracene (2AA) for strain TA100. The concentrations used for this test compound were 100, 200 and 400 µg per plate. Viscum album L. var. coloratum agglutinin showed moderate, but not negligible, protective effects regarding the antimutagenic properties against the direct-acting mutagens NaN(3) and AF-2. Furthermore, VCA was more effective in preventing the mutagenicity of the indirect-acting mutagen 2-AA (in the presence of S9) when tested with both TA98 and TA100. In conclusion, this report has shown broad ranging antimutagenic effects of VCA to numerous mutagens in TA98 and TA100 Salmonella typhimurium strains. Although the data presented here cannot be applied in vivo, they can support other antimutagenic and anticarcinogenic findings for VCA.

[Pectin substances of the callus culture of Silene vulgaris (M.) G].

Pectin-protein fraction SVC was isolated from the callus culture of the bladder campion (Silene vulgaris). The main components in it were residues of D-galacturonic acid, galactose, arabinose, rhamnose, and protein. Using ion-exchange chromatography, ultrafiltration, and acid and enzymatic hydrolysis, it was shown that SVC contained a mixture of molecules of linear pectin, branched pectin polysaccharide, and pectin-protein polymer. A fragment of the linear chain of galacturonan amounted to more than half of the entire carbohydrate silenan chain. The branched area of the macromolecule is represented by rhamnogalacturonan I. The pectin-protein polymer consisted mainly of protein and weakly branched pectin fragments with molecular mass of more than 300 kDa.

[Analysis of monosaccharides in Radix Rehmanniae by GC].

OBJECTIVE: To isolate and purify the polysaccharides from Radix Rehmanniae and analysis the monosaccharides composition. METHOD: The polysaccharides were extracted with hot water and precipitated by alcohol. Proteins in the precipitates were removed by TCA method. The products were further purified with column chromatography on Superdex 200 and Sephadex G100. The SRP I and SRP II were identified as homogeneous polysaccharide by HPLC, respectively, and then analyzed by GC after being hydrolysised. RESULT: Two homogeneous polysaccharides (SRP I and SRP II) were obtained from Radix Rehmanniae. CONCLUSION: SRP I contained rhamnose, arabinose, glucose and galactose in the percentage of 6.11%, 66.46%, 3.93% and 21.50%. SRP I was composed of rhamnose, fucose, mannose, galactose and fructose in the percentage of 21.82%, 24.47%, 10.48%, 29.94% and 13.29%.

Structural characterization of dietary fiber of green chalcumra (Benincasa hispida) fruit by NMR spectroscopic analysis.

A water-soluble dietary fiber was isolated from the hot aqueous extract of Chalcumra (Benincasa hispida) fruit. The polysaccharide was found to contain D-galactose and D-methyl galacturonate in a molar ratio of 2:1. On the basis of acid hydrolysis, methylation analysis, periodate oxidation, and NMR spectroscopic studies (1H, 13C, TOCSY, DQF-COSY, NOESY, ROESY, HMQC, and HMBC), the repeating unit of the polysaccharide was established as -->4)-beta-D-Galp-(1-->4)-beta-D-Galp-(1-->2)-alpha-D-GalpA6Me-( 1-->.

[Chemical studies on SC3, a polysaccharide from Salvia chinensis].

AIM: To study the chemical structure of SC3, an acidic polysaccharide from Salvia chinesis. METHODS: Based on chemical (including sugar composition analysis, methylation analysis, uronic acid reduction and partial acid hydrolysis) and spectral analysis (IR, NMR, ESI-MS), the structural characterization of SC3 was investigated. RESULTS: SC3 was composed Rha, Ara, Gal and GalA, with its mean molecular weight of 7.7 x 10(4). By means of methylation analysis, partial acid hydrolysis, NMR and ESI-MS spectrum, the linkages and sequence information of SC3 were obtained. CONCLUSION: SC3 is an complicated acidic polysaccharide, obtained for the first time from the plant.