Structural analysis of water-soluble polysaccharides in the fruiting body of Dictyophora indusiata and their in vivo antioxidant activities

The water-soluble Dictyophora indusiata polysaccharides (DIP) were extracted from the fruiting body of D. indusiata. The structural features of purified DIPs I and II were investigated. The results indicated that DIP I was composed of glucose (Glc) and mannose (Man) with molecular weight of 2100 kDa, while DIP II comprised of xylose (Xyl), galactose (Gal), glucose (Glc) and Man with molecular weight of 18.16 kDa. The glycosidic linkage of DIP I was composed of →1)-Glc-(6→: →1)-Man-(3,6→ with the ratio of 5.6:1.0, while DIP II was composed of →1)-Glc-(6→: →1)-Man-(3,6→: →1)-Xyl-(5→: →1)-Gal-(3→: →1)-Gal-(6→: with the ratio of 4.9: 15.5: 7.8: 1.0: 5.7. DIP significantly (P < 0.05) decreased the malondialdehyde (MDA), lipofuscin levels and increased the superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activities of mice. The strong in vivo antioxidant activity indicated DIP had great potential as functional food.     

In vitro antioxidant and antitumor activities of polysaccharides extracted from Asparagus officinalis

Ultrasonic circulating extraction technology was applied for the polysaccharide extraction from Asparagus officinalis. The crude polysaccharides were deproteinized by Sevag method and three main polysaccharide fractions, AOP-4, AOP-6 and AOP-8 were obtained by fractional precipitation with gradient concentrations of ethanol (40%, 60% and 80%). The in vitro antitumor and antioxidant activities of the polysaccharide fractions were evaluated by MTT assay and free radical-scavenging assay, respectively. Deproteinized AOPs showed higher antioxidant and antitumor activities than crude AOP. AOP-4 with molecular weight 5.75 × 10⁴ Da showed significant function of scavenging hydroxyl radical. Three AOP fractions had significant antitumor activity against HeLa and BEL-7404 cells in a dose dependent manner. Furthermore, the inhibit activity of AOP-4 against HeLa cells was higher than those of other AOPs and the inhibition rate reached 83.96% at the concentration of 10 mg/mL. These results indicated that the AOP might be useful for developing natural safe antitumor drugs or health food.     

Antioxidant and immunological activities of water-soluble polysaccharides from Aconitum kusnezoffii Reichb

Aconitum kusnezoffii Reichb., one of the earliest recorded toxic species of genus Aconitum, has been used as traditional Chinese medicine and medicinal diet over the last 2500 years to treat heart failure congestion, neuralgia, rheumatism and gout, etc. In the present paper, four water-soluble polysaccharide fractions isolated from the tubers of A. kusnezoffii Reichb. were studied the antioxidant and immunological activities for the first time. In vitro antioxidant assays indicated that fraction WKCP-A had noticeable scavenging activities on DPPH radical, hydroxyl radical, superoxide anion, H₂O₂ and self-oxidation of 1,2,3-phentriol, ferrous ion-chelating ability and reducing power. Moreover, the in vivo immunological assay exhibited that fractions WKCP-A and WKHP could more significantly enhance splenic lymphocyte proliferation and macrophage phagocytosis than other fractions. Therefore, the water-soluble polysaccharides from A. kusnezoffii Reichb., especially WKCP-A, have the potential to be explored as novel natural antioxidants and immunostimulating agents for using in functional foods or medicine.     

Extraction, preliminary structural characterization, and antioxidant activities of polysaccharides from Salvia miltiorrhiza Bunge

Four polysaccharides were extracted from Salvia miltiorrhiza Bunge using hot water, ultrasonic, alkali, and enzyme methods. Preliminary structural characterization was conducted by physicochemical property, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) analyses. Antioxidant activities against 2,2-diphenyl-1-picryl-hydrazyl (DPPH), hydroxyl, and superoxide radicals were also evaluated. The physicochemical property analysis indicated the identicalness of the polysaccharide indices obtained by the hot water and ultrasonic methods. The indices obtained by the alkali and enzyme methods were significantly different. The FTIR spectra revealed the general characteristic absorption peaks of the four polysaccharides. The SEM images demonstrated significant differences in the surface features of the different polysaccharides. The antioxidant activity assay revealed the significant antioxidant activities of three polysaccharides. Overall, the polysaccharides from S. miltiorrhiza Bunge may have potential applications in the medical and food industries.     

Characterization and antioxidant activity of Ginkgo biloba exocarp polysaccharides

Ginkgo biloba exocarp polysaccharide (GBEP) was obtained by hot water extraction, the crude polysaccharide was deproteinized by Sevag method and fractionized by a DEAE Sepharose fast flow anion-exchange column. Five fragments were obtained, including neutral polysaccharide (GBEP-N) and four acidic polysaccharides (GBEP-A1, GBEP-A2, GBEP-A3 and GBEP-A4). GBEP-N and GBEP-A3 were further purified by Superdex 200 gel column chromatography. The resulted two fractions GBEP-NN, and GBEP-AA were characterized by FT-IR, and HPGFC (high pressure gel filtration chromatography). Monosaccharide composition was determined by RP-HPLC method of precolumn derivatization with 1-phenyl-3-5-pyrazolone. GBEP-NN was mainly composed of rhamnose, arabinose, mannose, glucose and galactose, while GBEP-AA was mainly made up of mannose, rhamnose, glucuronic acid, galacturonic acid, galactosamine, glucose, galactose, xylose, arabinose, and fucose. The crude GBEP exhibited certain antioxidant activity. At the concentration of 5 mg/mL, the hydroxyl radical scavenging effect of GBEP was 90.52%, greater than 77.37% for the positive control ascorbic acid.     

Carboxymethylation of polysaccharides from Auricularia auricula and their antioxidant activities in vitro

The chemical carboxymethylated polysaccharide (CMAAP), which is derived from the poorly water-soluble, crude polysaccharide from Auricularia auricula (AAP), was prepared. The degree of substitution of CMAAP was 0.857, and its solubility in water reached 0.6 mg/mL, much higher than that of AAP (0.1 mg/mL). One fraction, CMAAP22, was purified. Chemical analysis indicated that CMAAP22 was composed of mannose and glucose in a ratio of 1.06:1 with a molecular weight of 3.4 × 10⁶ Da. IR spectra and ¹³C NMR spectra indicated that the C2, C4 and C6 positions were partially substituted by -CH₂COOH. AFM revealed that CMAAP22 was spherical particle structure with a diameter of 80-300 nm. Moreover, the antioxidant activity of CMAAP22 was improved, nearly twice as much as that of the AAP, especially in the scavenging of DPPH and ABTS+.     

Antitumor activity of sulfated extracellular polysaccharides of Ganoderma lucidum from the submerged fermentation broth

Water-soluble extracellular polysaccharides are known to possess weak or no in vitro antitumor activity. In this experiment, a mixture of extracellular Ganoderma lucidum polysaccharides (GLP) from the submerged fermentation broth was sulfated and studied on their antitumor activity. The sulfated GLP performed significant inhibition on the proliferation of assayed carcinoma cells in a dose-dependent manner, and present a degree of substitution-dependent suppressing to HepG2 cells. Meanwhile, the sulfated GLP presented remarkable but not dose-dependent inhibition on Heps hepatona in mice. With same degree of substitution, the sulfation protocol with aminosulfonic acid-pyridine yielded GLP sulfates with higher activity on HepG2 cells. In comparison, the native GLP showed no or little antitumor activity on the assayed cell lines but remarkable inhibition on suppressing the proliferation of rat Heps. The highest in vivo inhibition rate of 55.5% provided by sulfated GLP was observed on suppressing the proliferation of rat Heps.     

Isolation and antioxidant activities of polysaccharides extracted from the shoots of Phyllostachys edulis (Carr.)

Polysaccharides extracted from Phyllostachys edulis (Carr.) are a group of hetero polysaccharides, and their antioxidant activities were investigated employing various established in vitro systems. Available data obtained with in vitro models suggested that among the three samples, B1 (extraction with water) showed significant inhibitory effects on superoxide radical and hydroxyl radical; its reducing power was also the strongest among the three samples. These results clearly establish the possibility that polysaccharides extracted from P. edulis could be effectively employed as ingredient in health or functional food, to alleviate oxidative stress. However, comprehensive studies need to be conducted in experimental animal models.     

Immunomodulation and antitumor activities of different-molecular-weight polysaccharides from Porphyridium cruentum

The extracellular polysaccharides (EPSs) isolated from Porphyridium cruentum were degraded by hermetical-microwave and H₂O₂ under ultrasonic waves. Six products were obtained with molecular weights of 6.53, 256, 606, 802.6, 903.3 and 1002 kDa. The antitumor and immunomodulatory activities of different-molecular-weight (MW) polysaccharides were evaluated by the S180-tumor-bearing mouse model in vivo and peritoneal macrophage activation in vitro. The degraded EPSs all showed clear immunomodulation to different extents. The MW of the EPSs had a notable effect on their activity. The 6.53-kDa fragment had the strongest immunoenhancing activity. Different doses of EPS all inhibited the growth of the implanted S180 tumor. The tumor inhibition index at high, middle and low doses was 53.3%, 47.5% and 40.5%, respectively. In addition, three different concentrations of EPS significantly increased lymphocyte proliferation, which indicated the unique mechanism of the antitumor effect of EPS.     

Antioxidant activity of a water-soluble polysaccharide purified from Pteridium aquilinum

A water-soluble crude polysaccharide, obtained from fern Pteridium aquilinum, was fractionated by DEAE-Sepharose Fast-Flow column chromatography, and purified by Sephacryl S-400 HR column chromatography. The average molecular weight (M_w) of the purified polysaccharide (PLP) is 458,000 Da. The monosaccharide components of PLP were characterized by gas chromatography (GC), and the majority of the monosaccharide components was glucose (relative mass 58.1%) with low levels of galactose, mannose, rhamnose, and arabinose (relative mass 18.7%, 6.8%, 10.2%, and 6.1%, respectively). The Fourier-transform infrared spectra (FTIR) of PLP revealed typical characteristics of polysaccharides. On the basis of the ferric-reducing antioxidant power assay (FRAP), DPPH radical-scavenging, the superoxide radical assay, and self-oxidation of 1,2,3-phentriol assay, the antioxidant activities of PLP were investigated. The purified polysaccharide was demonstrated to have strong reductive power (FRAP value: 827.6 μmol/L), moderate scavenging activities against DPPH radicals (83.1%) and superoxide radicals (60.5%), and moderate inhibiting power for self-oxidation of 1,2,3-phentriol (52.4%).     

Antioxidant activities of polysaccharides from Lentinus edodes and their significance for disease prevention

The crude polysaccharide (LEP) was extracted by hot water from the fruiting bodies of Lentinus edodes, and further purified by DEAE-cellulose and Sepharose CL-6B chromatography, giving three polysaccharide fractions coded as LEPA1, LEPB1 and LEPC1. In this study, their chemical and physical characteristics of polysaccharide fractions and antioxidant capacities, including scavenging activity against hydroxyl radicals, superoxide radicals and Fe²⁺-chelating ability, were valuated. The results showed that LEPC1 exhibited significantly antioxidant activity at a concentration-dependent manner. Therefore these results indicated that the water-extractable polysaccharide fraction was a potent antioxidant and could be developed to be new health medicine for fighting against various human diseases.     

Immunopontentiating and antitumor activities of the purified polysaccharides from Phellodendron chinese SCHNEID

The polysaccharide fractions were isolated and purified from Phellodendron chinese SCHNEID, and antitumor activities were examined at dosages of 2, 5 and 10 mg/100 g. F-7 and F-8 showed the highest tumor inhibitory activities (inhibition ratio 96.4 and 98.2% in 2 mg/100 g), and in dose of 5 mg/100 g, the inhibitory ratios were 95.3 and 97.5%, respectively. Furthermore, 10 mg/100 g of intraperitoneal (i.p.) injection gave 97.3 and 98.7% of inhibition. In oral administration, the inhibitory activities were not markedly observed, indicating that the polysaccharides are directly acting to immune system. Also the polysaccharides increased the number of circulating blood leukocytes and total peritoneal exudate cells. Although implantation of tumor cells greatly decreased the productivity of antibody (antibody-mediated) and T lymphocyte reactivity (delayed-type) as 6.3 from 9.3 and 5.9 from 7.7, represented by the increase of footpad thickness, respectively. The polysaccharides elevated the reactivity of T lymphocyte in tumor-bearing mice, which were rapidly recovered by discontinuance of sample treatments. Especially, F-2, F-5, F-7 and F-8 remarkably recovered the decreased sensitivity. When the effects on thymidylate synthase (TS) and thymidine kinase (TK) activities were determined, TS activities in the F-2 and F-7-treated mice were markedly suppressed to 73.7% and 79.5% of that in the control (p < 0.01), while there was little difference in TK activity with a slight decrease in F-2 only. However, in i.p. injection, TS activities in the F-2, F-5, F-7 and F-8-treated mice were markedly suppressed to 83% to 85% of that in the control (p < 0.01). Furthermore, there were also significant differences in TK activities in F-2, F-5, F-7 and F-8-treated mice (p < 0.05). These results clearly indicated that the i.p. injection is much effective to suppress tumor growth than oral administration.     

South African Lippia herbal infusions: Total phenolic content,antioxidant and antibacterial activities

Lippia javanica and Lippia scaberrima are used as herbal remedies and are commercially traded as health teas in southern Africa under the brands “Mosukujane” and “Musukudu”, respectively. This study evaluates the relationship between the presence of phenolic compounds and the antioxidant activities of infusions prepared from four Lippia species (L. javanica, L. scaberrima, L. rehmannii and L. wilmsii) indigenous to South Africa. The antioxidant activities of the infusions, determined by the 2,2-diphenylpycrylhydrazyl (DPPH) method, were also compared to those of popular black, green and herbal tea brands. Of the four indigenous species, infusions of L. javanica and L. wilmsii exhibited the highest antioxidant activities (EC₅₀: 358 and 525 µg/ml, respectively) and contained the most phenolic compounds (14.8 and 14.5 mg/ml of dry weight gallic acid equivalent, respectively). Antibacterial activities of methanolic extracts of the four Lippia species were determined against four human pathogens (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa). The extract of L. javanica was the most active against all the pathogens tested. Those Lippia species (L. javanica and L. wilmsii) previously reported to produce higher levels of the pharmacologically active phenylethanoid glycosides verbascoside and isoverbascoside, portrayed stronger antioxidant and antibacterial activities. This study gives credence to the use of infusions of these Lippia species for their general health benefits.     

Purification, antioxidant and moisture-preserving activities of polysaccharides from papaya

Polysaccharides extracted from papaya are a group of heteropolysaccharides, and their antioxidant activities and moisture-preserving activities were investigated employing various established in vitro systems. Available data obtained with in vitro models suggested that among the three samples, the second fraction (named after P2) showed significant inhibitory effects on superoxide, hydroxyl and DPPH radical; its reducing power was also the strongest. Data also reveal that P2 has strong in vitro moisture absorption and retention capacities as compared to hyaluronic acid and glycerol. These results clearly establish the possibility that polysaccharides extracted from papaya could be effectively employed as a type of natural moisturizer. However, comprehensive studies need to be conducted in experimental animal models.     

Identification of polysaccharides from pericarp tissues of litchi (Litchi chinensis Sonn.) fruit in relation to their antioxidant activities

A large number of polysaccharides are present in the pericarp tissues of harvested litchi fruits. A DEAE Sepharose fast-flow anion-exchange column and a Sephadex G-50 gel-permeation column were used to isolate and purify the major polysaccharides from litchi fruit pericarp tissues. Antioxidant activities of these major polysaccharide components were also evaluated. An aqueous extract of the polysaccharides from litchi fruit pericarp tissues was chromatographed on a DEAE anion-exchange column to yield two fractions. The largest amount of the polysaccharide fraction was subjected to further purification by gel filtration on Sephadex G-50. The purified product was a neutral polysaccharide, with a molecular weight of 14 kDa, comprised mainly of 65.6% mannose, 33.0% galactose and 1.4% arabinose. Analysis by Smith degradation indicated that there were 8.7% of (1-->2)-glycosidic linkages, 83.3% of (1-->3)-glycosidic linkages and 8.0% of (1-->6)-glycosidic linkages in the polysaccharide. Furthermore, different polysaccharide fractions extracted and purified from litchi fruit pericarp tissues exhibited strong antioxidant activities. Among these fractions, the purified polysaccharide had the highest antioxidant activity and should be explored as a novel potential antioxidant.     

Sulfated polysaccharides from Laminaria angustata: Structural features and in vitro antiviral activities

Sulfated polysaccharides potently inhibit the infectivity of herpes simplex virus (HSV) in cultured cells. In this study, we have analyzed sulfated xylogalactofucan and alginic acid containing fractions generated from Laminaria angustata, a marine alga. The xylogalactofucan that has apparent molecular mass of 56 ± 5 kDa and unusually low sulfate content contains, inter alia, 1,3-, 1,4- and 1,2-linked fucopyranosyl residues. The algin (molecular mass: 32 ± 5 kDa) contains gulo- (55.5%) and mannuronic (44.5%) acid residues. Introduction of sulfate groups enhanced the macromolecules capability to inhibit the infection of cells by HSV-1. The 50% inhibitory concentration (IC₅₀) values of these macromolecules against HSV-1 were in the range of 0.2-25 μg ml⁻¹ and they lacked cytotoxicity at concentrations up to 1000 μg ml⁻¹. The sulfate content appeared to be an important hallmark of anti-HSV-1 activity. Our results suggest the feasibility of inhibiting HSV attachment to cells by direct interaction of polysaccharides with viral particles.     

油茶果壳化学成分研究

为了解油茶(Camellia oleifera Abel.)果壳中的化学成分,从其95%乙醇提取物中分离得到10个化合物。经波谱数据分析分别鉴定为:3α-菠菜甾醇(1)、麦角甾-4,6,8(14),22-四烯-3-酮(2)、(R)-de-O-metillasiodiplodin(3)、4′,5,7-三羟基二氢黄酮(4)、大黄素(5)、6-乙基-5-羟基-2,7-二甲氧基-1,4-萘醌(6)、ω-羟基大黄素(7)、macrophorin A(8)、negunfurol(9)、1-(3′,5′-二甲氧基)苯基-2-(4″-羟基)苯基乙烷(10)。化合物1~9为首次从油茶中分离得到,化合物2、3、5~9为首次从山茶属植物中分离得到。     

Antibacterial and antioxidant activities of four kaempferol methyl ethers isolated from Dodonaea viscosa Jacq. var. angustifolia leaf extracts

Fractionation of dichloromethane and acetone fractions obtained by serial extraction from the leaf powder of Dodonaea viscosa Jacq. var. angustifolia (Sapindaceae) resulted in the isolation of four kaempferol methyl ethers. The compounds were identified by spectral data (¹H NMR, ¹³C NMR and MS) as: 3, 5, 7-trihydroxy-4'-methoxyflavone (1); 5, 7, 4'-trihydroxy-3, 6-dimethoxyflavone (2); 5, 7-dihydroxy-3, 6, 4'-trimethoxyflavone (santin) (3); and 5-hydroxy -3, 7, 4'-trimethoxyflavone (4) together with 3,4',5,7-tetrahydroxy flavone (kaempferol) (5). Antioxidant potential of the compounds was evaluated using a DPPH spectrophotometric assay, while antibacterial activity was determined using a serial dilution microplate technique. The isolates demonstrated varying degrees of antioxidant and antibacterial activities. Of all the compounds investigated, compounds 1 and 5 demonstrated some antioxidant activity (EC₅₀ = 75.49 ± 1.76 µM and 35.06 ± 0.85 respectively) but lower than l-ascorbic acid (EC₅₀ = 13.55 ± 0.28 µM) used as a standard antioxidant agent. The minimum inhibitory concentration (MIC) of isolated compounds against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa varied from 16 µg/ml to more than 250 µg/ml. Some structure activity relationships could be established for these compounds.     

Effect of acetylation on antioxidant and cytoprotective activity of polysaccharides isolated from pumpkin (Cucurbita pepo, lady godiva)

Acetylation of pumpkin (Cucurbita pepo, lady godiva variety) polysaccharide using acetic anhydride with pyridines as catalyst under different conditions was conducted to obtain different degrees of acetylation on a laboratory scale. Furthermore, antioxidant activities and cytoprotective effects of pumpkin polysaccharide and its acetylated derivatives were investigated employing various established in vitro systems. Results showed that addition of pyridine as catalyst could increase the degree of substitution, whereas volume of acetic anhydride had little effect. The acetylated polysaccharides in DPPH scavenging radical activity assay, superoxide anion radical activity assay and reducing power assay exhibited higher antioxidant activity than that of unmodified polysaccharide. H₂O₂-induced oxidative damages on rat thymic lymphocyte were also prevented by pumpkin polysaccharide and its acetylated derivatives and the derivatives presented higher protective effects. On the whole, acetylated polysaccharide showed relevant antioxidant activity both in vitro and in a cell system.     

Chromones from the tubers of Eranthis cilicica and their antioxidant activity

Chemical studies on the constituents of Eranthis cilicica led to isolation of ten chromone derivatives, two of which were previously known. Comprehensive spectroscopic analysis, including extensive 1D and 2D NMR data, and the results of enzymatic hydrolysis allowed the chemical structures of the compounds to be assigned as 8,11-dihydro-5-hydroxy-2,9-dihydroxymethyl-4H-pyrano[2,3-g][1]benzoxepin-4-one, 5,7-dihydroxy-8-[(2E)-4-hydroxy-3-methylbut-2-enyl]-2-methyl-4H-1-benzopyran-4-one, 5,7-dihydroxy-2-hydroxymethyl-8-[(2E)-4-hydroxy-3-methylbut-2-enyl]-4H-1-benzopyran-4-one, 7-[(β-d-glucopyranosyl)oxy]-5-hydroxy-8-[(2E)-4-hydroxy-3-methylbut-2-enyl]-2-methyl-4H-1-benzopyran-4-one, 7-[(β-d-glucopyranosyl)oxy]-5-hydroxy-2-hydroxymethyl-8-[(2E)-4-hydroxy-3-methylbut-2-enyl]-4H-1-benzopyran-4-one, 9-[(O-β-d-glucopyranosyl-(1→6)-β-d-glucopyranosyl)oxy]methyl-8,11-dihydro-5,9-dihydroxy-2-methyl-4H-pyrano[2,3-g][1]benzoxepin-4-one, 8,11-dihydro-5,9-dihydroxy-9-hydroxymethyl-2-methyl-4H-pyrano[2,3-g][1]benzoxepin-4-one, and 7-[(O-β-d-glucopyranosyl-(1→6)-β-d-glucopyranosyl)oxy]methyl-4-hydroxy-5H-furo[3,2-g][1]benzopyran-5-one, respectively. The isolated compounds were evaluated for their antioxidant activity.