Chromatographic immunoassays for Helicobacter pylori detection – are they reliable in Mali, West Africa?

Introduction: Gastrointestinal diseases are major reasons for morbidity in Mali. As Helicobacter pylori is known to play a major role in gastritis and gastric ulcer we wanted to find a simple method for detection. Methods: Twenty-nine volunteers with confirmed gastric ulcer by gastroscopy and 59 randomly selected volunteers were diagnosed by using the rapid serological test Clearview®H. Pylori . The ImmunoCard STAT!® HpSA®test was applied on stool from 65 volunteers seeking help for gastrointestinal related ailments. Results: A Helicobacter pylori prevalence of 21% was found among the individuals with confirmed gastric ulcer, 44% among the randomly selected volunteers and 14% in individuals with gastrointestinal related ailments. Conclusion: According to what is already known about the aetiology of gastric ailments and the prevalence of Helicobacter pylori in neighboring countries, the infection rates in our study appear strikingly low. This might indicate that Clearview® H. Pylori and ImmunoCard STAT!® HpSA® have low sensitivities in the populations studied. Strain variability of H. Pylori may be an explanation. The tests need to be properly evaluated in Mali before they can be relied upon as diagnostic tools.Pan African Medical Journal 2013; 14: 7

Polysaccharides from the South African medicinal plant Artemisia afra: Structure and activity studies

Artemisia afra (Jacq. Ex. Willd), is an indigenous plant in South Africa and other parts of the African continent, where it is used as traditional medicine mostly for respiratory conditions. The objective of this study was to investigate the structural features of the polysaccharides from the leaves of this plant, as well as the biological activities of the polysaccharide fractions against the complement assay. Leaves of Artemisia afra were extracted sequentially with organic solvents (dichloromethane and methanol), 50% aqueous ethanol, and water at 50 and 100 °C respectively. The polysaccharide extracts were fractionated by ion exchange chromatography and the resulting fractions were tested for biological activity against the complement fixation assay. Active fractions were further fractionated using gel filtration. Monosaccharide compositions and linkage analyses were determined for the relevant fractions. Polysaccharides were shown to be of the pectin type, and largely contain arabinogalactan, rhamnogalacturonan and homogalacturonan structural features. The presence of arabinogalactan type II features as suggested by methylation analysis was further confirmed by the ready precipitation of the relevant polysaccharides with the Yariv reagent. An unusual feature of some of these polysaccharides was the presence of relatively high levels of xylose as one of its monosaccharide constituents. Purified polysaccharide fractions were shown to possess higher biological activity than the selected standard in the complement assay. Digestion of these polysaccharides with an endo-polygalacturonase enzyme resulted in polymers with lower molecular weights as expected, but still with biological activity which exceeded that of the standard. Thus on the basis of these studies it may be suggested that immunomodulating properties probably contribute significantly to the health-promoting effects of this medicinal plant

Structural elucidation of novel pro-inflammatory polysaccharides from Daphne mezereum L.

Daphne mezereum L., an important medicinal plant in Scandinavian folk medicine, was used to treat ailments such as diarrhea, swelling and stomach pain. A range of natural compounds have been isolated, but little attention has been given to the polysaccharides in this plant. Previous work in our group have shown that a polysaccharide enriched fraction from the bark of D. mezereum exhibited pro-inflammatory effects. To pursue this further, the aim of the present work was to isolate and characterize these polysaccharides. From the ethanol-precipitate of a water extract, one neutral (DMP-NF) and one acidic (DMP-AF) fraction was isolated by anion-exchange chromatography. GC, GC–MS and 1D- and 2D-NMR were used to characterize the polysaccharide structures. DMP-NF appeared to be a mixture of arabinan, arabinogalactan and hemicelluloses such as xyloglucan, mannan and xylan. DMP-AF contained a pectic polysaccharide mainly consisting of an unusually long homogalacturonan backbone. Enzymatic treatment by pectinase of DMP-AF yielded DMP-ED, which contained a rhamnogalacturonan-I backbone with arabinan, galactan and arabinogalactan side chains. Both DMP-NF and DMP-ED induced IFN-γ and TNF-α secretion in peripheral blood mononuclear cells (PBMCs), DMP-ED being the most potent fraction. DMP-AF was less active, which might be due to a less sterically available rhamnogalacturonan-I domain.</p

Phytochemical characterization and anti-inflammatory activity of a water extract of Gentiana purpurea roots

Ethnopharmacological relevance Gentiana purpurea was one of the most important medicinal plants in Norway during the 18th and 19th centuries, and the roots were used against different types of gastrointestinal and airway diseases. Aim of the study To explore the content of bioactive compounds in a water extract from the roots, a preparation commonly used in traditional medicine in Norway, to assess the anti-inflammatory potential, and furthermore to quantify the major bitter compounds in both roots and leaves. Materials and methods G. purpurea roots were boiled in water, the water extract applied on a Diaion HP20 column and further fractionated with Sephadex LH20, reverse phase C18 and normal phase silica gel to obtain the low molecular compounds. 1D NMR, 2D NMR, and ESI-MS were used for structure elucidation. HPLC-DAD analysis was used for quantification. The inhibition of TNF-α secretion in ConA stimulated peripheral blood mononuclear cells (PBMCs) was investigated. Results Eleven compounds were isolated and identified from the hot water extract of G. purpurea roots. Gentiopicrin, amarogentin, erythrocentaurin and gentiogenal showed dose-dependent inhibition of TNF-α secretion. Gentiopicrin is the major secondary metabolite in the roots, while sweroside dominates in the leaves. Conclusions The present work gives a comprehensive overview of the major low-molecular weight compounds in the water extracts of G. purpurea, including metabolites produced during the decoction process, and show new anti-inflammatory activities for the native bitter compounds as well as the metabolites produced during preparation of the crude drug

Pectic polysaccharides from Aconitum carmichaelii leaves protects against DSS-induced ulcerative colitis in mice through modulations of metabolism and microbiota composition

The industrial processing of Aconitum carmichaelii roots for use in Traditional Chinese Medicine generates a high amount of waste material, especially leaves. An acidic polysaccharide fraction isolated from these unutilized leaves, AL-I, was in our previous work shown to contain pectic polysaccharides. This study aimed to investigate the protective effect of AL-I on ulcerative colitis for the possible application of A. carmichaelii leaves in the treatment of intestinal inflammatory diseases. AL-I was found to alleviate symptoms and colonic pathological injury in colitis mice, and ameliorate the levels of inflammatory indices in serum and colon. The production of short- and branched-chain fatty acids was also restored by AL-I. The observed protective effect could be due to the inhibition of NOD1 and TLR4 activation, the promotion of gene transcription of tight-junction proteins, and the modulation of gut microbiota composition like Bacteroides, Dubosiella, Alistipes and Prevotella,. A regulation of serum metabolomic profiles being relevant to the bacterial change, such as D-mannose 6-phosphate, D-erythrose 4-phosphate and uric acid, was also observed

Structural characterization of bioactive heteropolysaccharides from the medicinal fungus Inonotus obliquus (Chaga).

The aim of this paper was to perform a comprehensive characterization of polysaccharides isolated from the interior (IOI) and exterior (IOE) parts of the fungus Inonotus obliquus. Pre-extraction with DCM and MeOH, followed by water and alkali extraction and ethanol precipitation gave two water extracts and two alkali extracts. Neutral and acidic polysaccharide fractions were obtained after anion-exchange chromatography of the water extracts. The neutral polysaccharides (60–73 kDa) were heterogeneous and branched and consisted of a (1 → 3)-linked β-Glc backbone with (1 → 6)-linked kinks in the chain at approximately every fifth residue, with branches of (1 → 6)-linked β-Glc in addition to substantial amounts of (1 → 6)-linked α-Gal with 3-O-methylation at about every third Gal residue. The acidic polysaccharide fractions (10–31 kDa) showed similar structural motifs as the neutral fractions differing mainly by the presence of (1 → 4)-linked α-GalA and α-GlcA. β-Xyl, α-Man and α-Rha were also present in varying amounts in all fractions. No major structural differences between the IOI and IOE fractions were observed. An alkaline polysaccharide fraction (>450 kDa) was obtained from the IOI alkali extract, and consisted mainly of (1 → 3)- and (1 → 6)-linked β-Glc and (1 → 4)-linked β-Xyl. Several of the fractions showed in vitro immunomodulatory effect by increasing NO production in the murine macrophage and dendritic cell lines J774.A1 and D2SC/1. Most fractions managed to increase NO production only at the highest concentration tested (100 μg/ml), while the neutral fraction IOE-WN activated potent NO production at 10 μg/ml and was considered the most promising immunomodulating fraction in this study

Complement Fixing Polysaccharides from Terminalia macroptera Root Bark, Stem Bark and Leaves

The root bark, stem bark and leaves of Terminalia macroptera were sequentially extracted with ethanol, 50% ethanol-water, and 50 °C and 100 °C water using an accelerated solvent extractor. Ten bioactive purified polysaccharide fractions were obtained from those crude extracts after anion exchange chromatography and gel filtration. The polysaccharides and their native extracts were characterized with respect to molecular weight, chemical compositions and effects in the complement assay. The chemical compositions showed that the polysaccharides are of pectic nature. The results indicated that there was no great difference of the complement fixation activities in the crude extracts from the different plant parts when extracting with the accelerated solvent extraction system. The purified polysaccharide fractions 100WTSBH-I-I and 100WTRBH-I-I isolated from the 100 °C water extracts of stem and root bark respectively, showed the highest complement fixation activities. These two fractions have rhamnogalacturonan type I backbone, but only 100WTSBH-I-I contains side chains of both arabinogalactan type I and II. Based on the yield and activities of the fractions studied those from the root bark gave highest results, followed by those from leaves and stem bark. But in total, all plant materials are good sources for fractions containing bioactive polysaccharides

Fungal polysaccharides from Inonotus obliquus are agonists for Toll-like receptors and induce macrophage anti-cancer activity

Abstract Fungal polysaccharides can exert immunomodulating activity by triggering pattern recognition receptors (PRRs) on innate immune cells such as macrophages. Here, we evaluate six polysaccharides isolated from the medicinal fungus Inonotus obliquus for their ability to activate mouse and human macrophages. We identify two water-soluble polysaccharides, AcF1 and AcF3, being able to trigger several critical antitumor functions of macrophages. AcF1 and AcF3 activate macrophages to secrete nitric oxide and the pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). Combined with interferon-γ, the fungal polysaccharides trigger high production of IL-12p70, a central cytokine for antitumor immunity, and induce macrophage-mediated inhibition of cancer cell growth in vitro and in vivo. AcF1 and AcF3 are strong agonists of the PRRs Toll-like receptor 2 (TLR2) and TLR4, and weak agonists of Dectin-1. In comparison, two prototypical particulate β-glucans, one isolated from I. obliquus and one from Saccharomyces cerevisiae (zymosan), are agonists for Dectin-1 but not TLR2 or TLR4, and are unable to trigger anti-cancer functions of macrophages. We conclude that the water-soluble polysaccharides AcF1 and AcF3 from I. obliquus have a strong potential for cancer immunotherapy by triggering multiple PRRs and by inducing potent anti-cancer activity of macrophages

Purification and Partial Structural Characterization of a Complement Fixating Polysaccharide from Rhizomes of Ligusticum chuanxiong

Rhizome of Ligusticum chuanxiong is an effective medical plant, which has been extensively applied for centuries in migraine and cardiovascular diseases treatment in China. Polysaccharides from this plant have been shown to have interesting bioactivities, but previous studies have only been performed on the neutral polysaccharides. In this study, LCP-I-I, a pectic polysaccharide fraction, was obtained from the 100 °C water extracts of L. chuangxiong rhizomes and purified by diethylaminethyl (DEAE) sepharose anion exchange chromatography and gel filtration. Monosaccharide analysis and linkage determination in addition to Fourier transform infrared (FT-IR) spectrometer and Nuclear magnetic resonance (NMR) spectrum, indicated that LCP-I-I is a typical pectic polysaccharide, with homo-galacturonan and rhamnogalacturonan type I regions and arabinogalactan type I and type II (AG-I/AG-II) side chains. LCP-I-I exhibited potent complement fixation activity, ICH50 of 26.3 ± 2.2 µg/mL, and thus has potential as a natural immunomodulator