Purification, characterization and immunostimulatory effects of polysaccharides from Anemarrhena asphodeloides rhizomes.

The crude polysaccharide was extracted from A. asphodeloides rhizomes and further purified to produce two fractions F1 (50.0%) and F2 (19.6%). The chemical constitutions of the polysaccharides were neutral sugars (51.4%-89.7%), uronic acids (1.0%-30.2%) and sulfate esters (3.4%-8.1%), with various ratios of monosaccharides including rhamnose (1.4%-6.1%), arabinose (7.1%-21.2%), xylose (0.2%-4.8%), mannose (39.9%-79.0%), glucose (6.0%-11.1%) and galactose (2.6%-22.0%). The molecular properties of the polysaccharides were investigated by the HPSEC-UV-MALLS-RI system, revealing the Mw 130.0 × 103-576.5 × 103 g/moL, Rg 87.6-382.6 nm and SVg 0.3-54.3 cm3/g. The polysaccharides stimulated RAW264.7 cells to produce considerable amounts of NO and up-regulate the expression of TNF-α, IL-1 and COX-2 genes. Polysaccharides exhibited the growth inhibitory effects on cancer cells lines of AGS, MKN-28 and MKN-45, in which F2 fraction exhibited prominent bioactivities. The AGS cells treated with F2 experienced condensed cytoplasm, shrinkage of nucleus and chromatin marginalization with the highest number of cells at early-stage apoptosis reaching 54.6%. The inhibitory effect of F2 polysaccharide on AGS cells was through MAPKs and STAT3 signaling pathways. The backbone of the F2 was mainly linked by (1 â†’ 4)-linked mannopyranosyl and (1 â†’ 3)-linked galactopyranosyl. Taken together, the polysaccharide from A. asphodeloides rhizomes could be utilized as medicinal, pharmacological and functional food ingredients.

Studies on chemical composition, rheological and antioxidant properties of pectin isolated from Riang (Parkia timoriana (DC.) Merr.) pod.

Although synthetic antioxidant food additives are widely used in a variety of food products, some of them are suspected of having a noxious effect on human health. As a consequence, much research attention has been focused on developing natural antioxidant compounds from plants. Riang (Parkia timoriana (DC.) Merr.) is known as a traditional medicinal plant in which its various parts have been reported to exhibit antioxidant and numerous biological activities. In this study, pectins from Riang pod husk and pod powder were extracted, and their physico-chemical, rheological, and antioxidant properties were characterized. The extracted pectins showed high uronic acid content (> 65%) and high molecular weight (200-250 kDa) and the yields were approximately 15 and 36%w/w (dry basis), for Riang husk pectin (RHP) and Riang pod powder pectin (RPP), respectively. Furthermore, both pectins were classified as a high methoxyl with their DE of ~66%. Rheological measurements revealed a pseudoplastic behavior above 2% w/v. RHP contained higher content of total phenolics, flavonoids and tannin, compared with RPP. Antioxidant activities of RHP were consequently higher than RPP in all studied assays. The highest antioxidant activities of RHP and RPP, obtained from ABTS assay, were 0.95 and 0.24 mmol Trolox equivalents/g, respectively.

Effects of polysaccharides from abalone viscera (Haliotis discus hannai Ino) on MGC 803 cells proliferation.

The polysaccharides (AVP) was obtained from abalone (Haliotis discus hannai Ino) viscera, using the alkaline protease to enzymolysis, sevage method and repeated freezing and thawing method to remove protein and hydrogen peroxide method to depigment. The total sugar content was 46.27±1.5% and uronic acid, sulfate radical, hexosamine and protein contents were 17.44±0.22%, 16.98±0.15%, 0.65±0.02% and 1.64±0.13% in AVP respectively. The main monosaccharide compositions of AVP were d-galactose, d-xylose, d-mannose, d-glucose and d-glucuronic acid. MTT assay showed AVP had a significant anti-tumor activity to gastric carcinoma cells, especially to MGC 803, while it had no influence upon proliferation of normal stomach cells GES 1. The results of Morphological changes, cell migration ability and AO/EB staining indicated that MGC803 cells underwent apoptosis in a dose-dependent manner induced by AVP. Moreover, the western blotting results showed that the expressions of survivin, Bcl-2 and VEGF were decreased, while the expression of Bax and p53 were increased in a dose-dependent manner of AVP. The results suggested that AVP might be a potential anti-tumor agent securely and naturally.

Unexpected features of exponentially growing Tobacco Bright Yellow-2 cell suspension culture in relation to excreted extracellular polysaccharides and cell wall composition.

This article presents a new insight about TBY-2 cells; from extracellular polysaccharides secretion to cell wall composition during cell suspension culture. In the medium of cells taken 2 days after dilution (end of lag phase), a two unit pH decrease from 5.38 to 3.45 was observed and linked to a high uronic acid (UA) amount secretion (47.8%) while, in 4 and 7 day-old spent media, pH increased and UA amounts decreased 35.6 and 42.3% UA, respectively. To attain deeper knowledge of the putative link between extracellular polysaccharide excretion and cell wall composition, we determined cell wall UA and neutral sugar composition of cells from D2 to D12 cultures. While cell walls from D2 and D3 cells contained a large amount of uronic acid (twice as much as the other analysed cell walls), similar amounts of neutral sugar were detected in cells from lag to end of exponential phase cells suggesting an enriched pectin network in young cultures. Indeed, monosaccharide composition analysis leads to an estimated percentage of pectins of 56% for D3 cell wall against 45% D7 cell walls indicating that the cells at the mid-exponential growth phase re-organized their cell wall linked to a decrease in secreted UA that finally led to a stabilization of the spent medium pH to 5.4. In conclusion, TBY-2 cell suspension from lag to stationary phase showed cell wall remodeling that could be of interest in drug interaction and internalization study.

Purification, structural characterization and anticancer activity of the novel polysaccharides from Rhynchosia minima root.

Three novel acidic polysaccharides termed PRM1, PRM3 and PRM5 were purified from Rhynchosia minima root using DEAE-52 cellulose and sephadex G-150 column chromatography. Their structures were characterized by ultraviolet (UV) and Fourier transform infrared (FTIR) spectrometry, gel permeation chromatography (GPC), gas chromatography-mass spectrometry (GC-MS), and differential scanning colorimeter (DSC) analysis. The uronic acid contents of PRM1, PRM3 and PRM5 were 30.7%, 12.7% and 47.7%, respectively. PRM1 (143.2 kDa), PRM3 (105.3 kDa) and PRM5 (162.1 kDa) were heteropolysaccharides because they were composed of arabinose, mannose, glucose and galactose. Their enthalpy values were 201.0, 111.0 and 206.8 J/g, respectively. PRM3 and PRM1 exhibited strong in vitro anticancer activity against lung cancer A549 and liver cancer HepG2 cells in a dose-dependent manner. These findings suggested that PRM1 and PRM3 could be potentially developed as natural anticancer agents.

Characterization and immunomodulatory activities of polysaccharides from Spirogyra neglecta (Hassall) Kützing.

Sulfated polysaccharides (SP) isolated from freshwater green algae, Spirogyra neglecta (Hassall) Kützing, and fractionated SPs were examined to investigate their molecular characteristics and immunomodulatory activity. The crude and fractionated SPs (F1, F2, and F3) consisted mostly of carbohydrates (68.5-85.3%), uronic acids (3.2-4.9%), and sulfates (2.2-12.2%) with various amounts of proteins (2.6-17.1%). D-galactose (23.5-27.3%), D-glucose (11.5-24.8%), L-fucose (19.0-26.7%), and L-rhamnose (16.4-18.3%) were the major monosaccharide units of these SPs with different levels of L-arabinose (3.0-9.4%), D-xylose (4.6-9.8%), and D-mannose (0.4-2.3%). The SPs contained two sub-fractions with molecular weights (Mw) ranging from 164 × 10(3) to 1460 × 10(3) g/mol. The crude and fractionated SPs strongly stimulated murine macrophages, producing considerable amounts of nitric oxide and various cytokines via up-regulation of their mRNA expression by activation of nuclear factor-kappa B and mitogen-activated protein kinases pathways. The main backbone of the most immunoenhancing SP was (1→3)-L-Fucopyranoside, (1→4,6)-D-Glucopyranoside, and (1→4)-D-Galactopyranoside.

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.

A comparison between high hydrostatic pressure extraction and heat extraction of ginsenosides from ginseng (Panax ginseng CA Meyer).

BACKGROUND: To determine biomaterial components, the components must first be transferred into solution; thus extraction is the first step in biomaterial analysis. High hydrostatic pressure technology was used for ginsenoside extraction from ginseng roots. In the extraction of fresh and red ginseng, high hydrostatic pressure extraction (HHPE) was found to be more effective than heat extraction (HE). RESULTS: In fresh ginseng extraction under HHPE, total ginsenosides (1602.2 µg mL⁻¹) and ginsenoside metabolite (132.6 µg mL⁻¹) levels were slightly higher than those under HE (1259.0 and 78.7 µg mL⁻¹), respectively. In red ginseng, similar results indicated total ginsenoside and ginsenoside metabolite amounts according to the extraction methods. Most volatile compounds by HHPE were higher than by HE treatment. HHPE of red ginseng was conducted under four pressures: 0.1 MPa (1 atm), 30, 50, and 80 MPa. Total sugar, uronic acid, and polyphenol amounts increased until 30 MPa of pressure and then showed decreasing tendencies. Total ginsenoside and ginsenoside metabolite contents linearly increased with increasing pressure, and a maximum was reached at 80 MPa for the metabolites. CONCLUSION: HHPE used for red ginseng processing contributes to enhanced extraction efficiencies of functional materials such as ginsenosides through cell structure modification.

The tumor necrosis factor-inducing potency of lipopolysaccharide and uronic acid polymers is increased when they are covalently linked to particles.

Lipopolysaccharide (LPS) and polymers of the uronic acid family stimulate monocytes to produce tumor necrosis factor (TNF). The TNF-inducing potency of these polysaccharides may depend on their supramolecular configuration. In this study detoxified LPS and uronic acid polymers have been covalently linked to particles which have been added to monocytes under serum-free conditions. Reducing the size of mannuronan from 350,000 to 5,500 Da (M-blocks) led to a 10- to 100-fold reduction in TNF-inducing potency. However, covalently linking the M-blocks to monodisperse suspensions of magnetic particles increased the TNF-inducing potency by up to 60,000-fold. Also, the TNF-inducing potency of glucuronic acid polymers was increased when they were linked to particles, but no potentiation was observed with guluronic acid blocks covalently attached to particles. Furthermore, O chains of LPS (detoxified LPS) became potent TNF inducers when they were presented to monocytes on a particle surface. No activation of the LPS-responsive SW480 adenocarcinoma cells was found with detoxified LPS or M-block particles, suggesting a preference for cells expressing CD14 and/or other membrane molecules. The potentiating effects were not restricted to polymers attached to aminated magnetic particles. Of particular interest, we found that short blocks of mannuronan induced TNF production also when covalently linked to biodegradable, bovine serum albumin particles.

[Components of proteoglycan aggregates in human hyaline cartilage]. / Izuchenie komponentov proteoglikanovykh agregatov gialinovogo khriashcha cheloveka.

The components of proteoglycan aggregates--proteoglycan subunits and link proteins from articular cartilage extracts of newborns--were isolated and purified. The content of extracted uronic acids and protein per 1 g of wet weight was 4.77 +/- 0.52 and 3.19 +/- 0.14 mg, respectively. The components of proteoglycan aggregates were isolated and purified by caesium chloride density gradient ultracentrifugation under association and dissociation conditions, as well as by gel filtration on Sephacryl S-200. The uronic acids/protein ratio for proteoglycan subunits was equal to 59.13 +/- 10.19, their relative electrophoretic mobility was 0.54 +/- 0.01 (the mobility of the chondroitin sulfate was taken for unity). The IR spectra of proteoglycan subunits were characterized. Three link proteins with Mr 48 000, 44 000 and 41 500 were isolated from proteoglycan aggregates and characterized. The protein with Mr 48 000 was predominant.

Metabolism of acid mucopolysaccharides in hepatoma and in normal liver.

The metabolism of acid mucopolysaccharides in Novikoff hepatoma and in hepatoma BW7756 was studied using the precursors -35S-sulfate, -H-glucosamine and -14C-galactosamine. There is an active formation of sulfated mucopolysaccharides at the mitochondria and cell membrane level. Hepatoma cells synthesize heparin to a lower rate than liver cells. In ascitic as well as in solid tumors there is a considerable accumulation of hyaluronic acid which does not seem to be elicited by the tumor cells but by the surrounding tissues. The possible implication of the low heparin production in the cell membrane characteristics is discussed.