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The polysaccharide (VSP) from the gum exudate of quaruba (Vochysia lehmannii) had two components of almost identical Mw centred at 24,800, as shown by HSPEC-MALLS. The presence of aggregates was shown since carboxy-reduction gave VSP-RED, which contained low molecular weight components with Mw 19,000>5800 and polydispersity ratios dn/dc 0.160 and 0.149, respectively. VSP formed low viscosity aqueous solutions and acid hydrolysis gave Man (30%), Ara (16%), Gal (10%), and Glc (14%). The latter arose partly from GlcA (30%). Methylation analysis revealed mainly neutral units of 2-O- (60%) and 2,3-di-O-substituted Manp (5%), and those of nonreducing ends (8%), 2-O- (3%),and 4-O-substituted Arap and/or 5-O-substituted Araf units (6%). VSP-RED contained Glc (45%), Man (35%), and Ara (13%) and methylation analysis indicated mainly 4-O-substituted Glcp (31%) and 2-O- (51%) and 2,3-di-O-substituted Manp units (5%). A predominant alternating structure for VSP was shown by its 13C NMR spectrum, which contained 10 main signals and a small one of C-6 of GlcpA. This was confirmed by formation, on partial hydrolysis of VSP, of a tetrasaccharide, which was characterised by NMR spectroscopy and ESI-MS as β-GlcpA-(1→2)-α-Manp-(1→4)-β-GlcpA-(1→2)-Man, which arose from the main chain, thus confirming VSP to be a glycoglucuronomannan. [Copyright &y& Elsevier]

A heteropolysaccharide was isolated by cold aqueous extraction from edible mushroom Pleurotus eryngii (“King Oyster”) basidiocarps and its biological properties were evaluated. Structural assignments were carried out using mono- and bidimensional NMR spectroscopy, monosaccharide composition, and methylation analyses. A mannogalactan having a main chain of (1 → 6)-linked α- d -galactopyranosyl and 3- O -methyl-α- d -galactopyranosyl residues, both partially substituted at OH-2 by β- d -Man p (MG- Pe ) single-unit was found. Biological effects of mannogalactan from P. eryngii (MG- Pe ) were tested against murine melanoma cells. MG- Pe was non-cytotoxic, but reduced in vitro melanoma cells invasion. Also, 50 mg/kg MG- Pe administration to melanoma-bearing C57BL/6 mice up to 10 days decreased in 60% the tumor volume compared to control. Additionally, no changes were observed when biochemical profile, complete blood cells count (CBC), organs, and body weight were analyzed. Mg- Pe was shown to be a promising anti-melanoma molecule capable of switching melanoma cells to a non-invasive phenotype with no toxicity to melanoma-bearing mice. [ABSTRACT FROM AUTHOR]

The formation of foams on lakes is a complex phenomenon whose origin is often hardly identifiable. Recently (2007, 2008, and 2010) foam episodes started to occur in Lake Maggiore, northern Italy. The present work aimed to verify the hypothesis of an endogenous-natural origin of these foams, driven by trophic or climatic changes. To this purpose, a long-term (2000-2013) analysis of phytoplankton biovolumes, meteorological, and hydrological data has been performed together with the chemical characterization of foams. Foams resulted of endogenous origin and likely related to phytoplankton biomass degradation. Data analysis highlighted atypical warm temperature and residual lake stratification in winter in two of the three years of foam events, coupled with exceptional Bacyllariophyceae blooms in spring. Tabellaria flocculosa mostly contributed in terms of biomass in 2007 and 2008, but not in 2010; thus overall algal biomass seemed a better predictor of the risk of foam formation. Foam events occurred from July to December, driven by atypically windy conditions, and congruently with the time needed to degrade biomass into surface-active compounds. A co-occurrence of different factors resulted essential to generate foams, and climate changes likely contribute to enhance their occurrence in Lake Maggiore. [ABSTRACT FROM AUTHOR]

Abstract: Pulp from peaches contained polygalacturonic acid and arabinogalactan as main polysaccharides, which were isolated and characterised. The polygalacturonic acid (AE-CWI) contained 95% GalA and its 13C NMR spectrum showed signals at δ 98.9, 78.0, 71.4, 69.1, 68.4, and 175.1 from C-1, C-4, C-5, C-3, C-2, and C-6 respectively, from (1→4)-linked α-GalpA units. Methylation-MS analysis of carboxy-reduced material (AE-CWI-CR) gave 90% of 2,3,6-Me3-galactitol acetate. The arabinogalactan (AE-AG) was composed mainly of Ara (41%) and Gal (50%) and was characterised (methylation analysis and 13C NMR) as a type II-arabinogalactan. It induced peritoneal macrophage activation in mice, ∼70% of cells treated with this fraction (1–50μg/mL) having morphology of activated cells. However, NO production in macrophages treated with AE-AG was not affected. This suggests a new biological activity for peach polysaccharides. [Copyright &y& Elsevier]

Abstract: For many years mushrooms have been consumed and appreciated by their nutritional value, and medicinal properties. The traditional mushroom cultivation takes too long and the macrofungi biotechnology has not been explored in its full potential yet. The goal of this work was to observe if different carbon sources could improve the yield and diversify fungi nutrient composition in submerged culture. Pleurotus pulmonarius mycelia and exopolysacharide productions were evaluated using glucose, galactose, xylose and arabinose. The mycelia yield varied depending on the culture medium, and galactose showed to be the best carbon source to produce EPS. Samples that showed the highest protein contents were grown with xylose (19.44%) and arabinose (26.05%). Furthermore, the biomass cultivated with these carbohydrates and with galactose showed five essential amino acids. All cultured biomass showed low lipid contents (∼1%), being composed mainly of unsaturated fatty acids. All EPS fractions showed as main structures glucans and mannogalactans. [Copyright &y& Elsevier]

Abstract: The pathogenic fungus Exophiala jeanselmei (Ej4) was grown in submerged MM medium, glucose being consumed after six days with maximum biomass and EPS production. Cells were extracted with CHCl3–MeOH (2:1, v/v) yielding a product containing 10% lipid, with high levels of unsaturated C18:1 (43.6%) and C18:2 (21.0%), 2D-TLC showed the presence of PE (17.7%), PS (11.6%), PC (35.8%), PI (1.2%) and lyso-phospholipids, LPE (10.7%), LPC (2.0%), PA (10.4%), cardiolipin (10.5%) and glucosyl-ceramide. Analysis of EPS-1 (120kDa) showed a galactomanan, containing a main chain of Manp-(1→2) (24.2%), substituted by side chains containing terminal Galf (16.8%) and Manp (3.5%) and acetyl groups attached at O-6 of terminal Galf. An immune response against antigens was obtained using Balb/C mice. Anti-EPS-1 antibodies recognized purified fraction containing cellular walls very titer and higher than 1:20,000 for EPS. The studied biomolecules showed biotechnological potential and point to important perspectives in diagnosis of fungi and immunomodulatory products. [Copyright &y& Elsevier]

Abstract: The peach tree (Prunus persica), after mechanical injury or infection by microorganisms, produces a copious gum exudate on its trunk and branches. After aqueous extraction, peach gum (cv. ‘chimarrita’) yielded a soluble aqueous extract (AE) and a particle-rich hydrogel fraction (RG). After freeze-drying, AE was solubilized in water and added to excess ethanol to give a polysaccharide (POLY) precipitate. RG, AE, and POLY were composed of Ara, Xyl, Man, Gal, and uronic acids in 46:14:2:32:6, 54:12:1:27:6, and 47:13:1:33:6 molar ratios respectively, with traces of Rha. The 13C NMR spectra of all fractions were similar, with C-1 signals of α-l-Araf (δ 109.6–107.4) and main ones from β-d-Galp units (δ 103.7, 103.2), suggesting the presence of arabinogalactan-type polysaccharides. Rheological analyses were carried out with AE and POLY. Solutions of both fractions at 4% (w/v) had a non-Newtonian shear-thinning behavior, however that of AE showed higher apparent viscosity than that of POLY. The presence of salts decreased the apparent viscosity of AE dispersion. Dynamic oscillatory analyses showed that 4% (w/v) AE and POLY had a gel-like structure, being AE hydrogel a stronger gel when compared with POLY. This suggests that other compounds, in addition to polysaccharide, are involved in the gel network in aqueous dispersions of AE. Weaker gels were formed with 2% (w/v) AE in water and 4% (w/v) AE in various salt solutions. These results showed that the peach gum had an interesting rheological behavior and that it could have a future application. [Copyright &y& Elsevier]

Abstract: Extracellular polysaccharide is a virulence factor of the most cariogenic bacteria, Streptococcus mutans. We describe a procedure for chemical analysis of this polysaccharide of S. mutans, using a well-known glucan synthesized by purified enzymes of cariogenic streptococci. Soluble and insoluble glucan from glucosyltransferase D and B respectively, were prepared and analyzed by nuclear magnetic resonance spectroscopy and methylation. Soluble α-glucan contained 60% of (1→6)-linkages and 17% of branching while insoluble α-glucan was composed of 57% of (1→3)- and 28% of (1→6)-linkages with 8% branching. The described procedure could be important focusing future studies on in vivo biofilm. [Copyright &y& Elsevier]

Bacteria from the genus Herbaspirillum are endophytes responsible for nitrogen fixation in gramineous plants of economic importance such as maize, sugarcane, sorghum, rice, and wheat. Some species are known to produce plant growth substances. In contrast, Herbaspirillum rubrisubalbicans strains are known to be mild plant pathogens. The molecular communication between the plant and the microbes might involve lipopolysaccharides present in the outer membrane of these gram-negative bacteria. Phenol-water extraction was used to obtain lipopolysaccharides from 7 strains of Herbaspirillum seropedicae (SmR1, Z67, Z78, ZA95, and M2) and H. rubrisubalbicans (M1 and M4). The electrophoretic profiles and chemical composition of the lipopolysaccharides obtained in the phenol and aqueous extracts were shown herein. Les bactéries du genre Herbaspirillum sont des endophytes responsables de la fixation d’azote chez les graminées d’importance économique telles le maïs, la canne à sucre, le sorgho, le riz et le blé. Quelques espèces sont connues pour produire des substances favorisant la croissance végétale. Au contraire, les souches de Herbaspirillum rubrisubalbicans sont des pathogènes végétaux bénins. La communication moléculaire entre les végétaux et les microbes peut impliquer des lipopolysaccharides présents sur le membrane externe de ces bactéries négatives à gram. Une extraction phénol-eau a été utilisée pour obtenir les lipopolysaccharides de 7 souches de Herbaspirillum seropedicae (SmR1, Z67, Z78, ZA95 et M2) et de H. rubrisubalbicans (M1 et M4). Les profils en électrophorèse et la composition chimique des LPS obtenus des extraits phénoliques et aqueux sont présentés ici. [ABSTRACT FROM AUTHOR]

Abstract: Cold aqueous extraction of basidiocarps (fruiting bodies) of the edible mushroom Lentinus edodes (shiitake) gave rise to a heteropolysaccharide, whose chemical structure, antinociceptive and anti-inflammatory properties were determined. Its chemical structure was based on monosaccharide composition, methylation analysis, and NMR spectroscopy (1H, 13C, HSQC, HSQC-TOCSY, HSQC-NOESY, and coupled HMQC). It was found to be a fucomannogalactan with a main chain of (1→6)-linked α-d-galactopyranosyl units, partially substituted at O-2 by single-unit β-d-Manp or α-l-Fucp side chains. The polysaccharide produced a marked and dose-related effect when assessed against acetic acid-induced visceral nociception. Prevention of peritoneal capillary permeability and leukocyte infiltration caused by the acetic acid was similar in potency and effectiveness. [Copyright &y& Elsevier]

Abstract: A polysaccharide (M w 2.39×104 g/mol) was extracted with cold water from the basidiomycete Pleurotus pulmonarius, and its antinociceptive and anti-inflammatory properties were evaluated. It was a mannogalactan (MG), whose structure was characterized using mono- and two-dimensional NMR spectroscopy, methylation analysis, and a controlled Smith degradation. It had a main chain of (1→6)-linked α-d-galactopyranosyl and 3-O-methyl-α-d-galactopyranosyl units, both of which are partially substituted at O-2 by β-d-mannopyranosyl non-reducing ends. The MG was tested for its effects on the acetic acid-induced writhing reaction in mice, a typical model for inflammatory pain, causing a marked and dose-dependent inhibition of the nociceptive response, with ID50 of 16.2 (14.7–17.7)mg/kg and inhibition of 93±3% at a dose of 30mg/kg. An inflammatory response was not inhibited. [Copyright &y& Elsevier]

Abstract: The gum exudate of S. romanzoffiana contained a heteropolysaccharide (SRP), which was isolated in 80% yield, contained Fuc, Ara, Xyl, Gal, Glc and uronic acid in a molar ratio of 23:25:41:1:3:8, and had . It was homogeneous with M w 1.4×105 and M w/M n∼1.0 and formed high viscosity, aqueous solutions. Carboxy-reduction provided neutral material (SRP-CR), having glucose and its 4-O-methyl derivative in a molar ratio of ∼3:1. Methylation analysis of SRP showed a highly branched structure with non-reducing end-units of Araf (16%), Fucp (10%) and Xylp (12%), 3-O- (5%), 2-O- (17%), 3,4- (7%) and 2,4-di-O-substituted Araf (10%), and 2,3,4-tri-O-susbtituted Xylp units (21%). The 13C-NMR spectrum of SRP was complex and contained at least 8 C-1 signals. The 13C-NMR spectrum and methylation analysis of Smith-degraded polysaccharide (SRP-SM) were consistent with a (1→4)-linked β-Xylp main chain. Partial hydrolysis of SRP gave rise to α-GlcpA-(1→2)-β-[Xylp-(1→4)]0-1-αβ-Xylp and 4-Me-α-GlcpA-(1→2)-αβ-Xylp. Milder hydrolysis conditions gave rise a mixture of oligosaccharides that were fractionated by charcoal–Celite column chromatography. The 10% aq. EtOH fraction (OL-10) gave a main GC spot with R Gal 1.2 and minor ones with R Gal 1.07 and 0.78, and was characterized as a mixture of β-Xylp-(1→2)-αβ-Xyl, Fucp-(1→4)-αβ-Xylp, and Fucp-(1→3)-αβ-Ara. Small amounts of fucobiose were also present. [Copyright &y& Elsevier]

Abstract: The three main polysaccharides from the lichenized fungus Umbilicaria mammulata were isolated and characterized. Their structures were determined using GC-MS of derived alditol acetates, GC-MS-methylation analysis and 13C NMR spectroscopy. Two of them were (1→3)-and (1→6)-linked β-glucans, namely laminaran and pustulan, respectively. The other was a galactofuranomannan, which was analyzed as well as a galactose-free polysaccharide formed on partial hydrolysis. The former consisted of a main chain of (1→6)-linked α-mannopyranosyl residues, part of them being substituted at O-2, O-4, and O-2,4 by complex, branched side chains containing α-mannopyranosyl and β-galactofuranosyl units. This heteropolysaccharide is related to those of other Umbilicariaceae, and its chemical characterization presents a useful tool for the systematics of lichenized fungi. [Copyright &y& Elsevier]

Abstract: A galactoglucomannan (GGM), isolated from the lichen Cladonia ibitipocae, consisted of a (1→6)-linked main chain of α-mannopyranose units, substituted by α- and β-d-galacto (α- and β-d-Galp)-, β-d-gluco (β-d-Glcp) - and α-d-mannopyranosyl (α-d-Manp) groups, and was sulfated giving a sulfated polysaccharide (GGM-SO4) with 42.2% sulfate corresponding to a degree of substitution of 1.29. NMR studies indicated that after sulfation, the OH-6 groups of galactopyranosyl and mannopyranosyl units were preferentially substituted. GGM-SO4 was investigated in terms of its in vitro anticoagulant and in vivo antithrombotic properties. Those of the former were evaluated by its activated partial thromboplastin (APTT) and thrombin time (TT), using pooled normal human plasma, and compared with that of 140USPunitsmg−1 for a porcine intestinal mucosa heparin. Anticoagulant activity was detected in GGM-SO4, but not in GGM. The in vivo antithrombotic properties of GGM-SO4 were evaluated using a stasis thrombosis model in Wistar rats, intravenous administration of 2mgkg−1 body weight totally inhibiting thrombus formation. It caused dose-dependent increases in tail transection bleeding time. The results obtained showed that this sulfated polysaccharides is a promising anticoagulant and antithrombotic agent. [Copyright &y& Elsevier]

A galactomannan was isolated from the cyanolichen Leptogium azureum via successive alkaline extraction and precipitation with Fehling solution. The structure of the polysaccharide was investigated using NMR spectroscopy, methylation analysis, Smith degradation, and HPSEC-MALLS. As galactomannans from other lichens species, the polymer obtained presents a (1→6)-linked main chain of α-mannopyranose, substituted preferentially at O-2 by α-Manp or β-Galp non-reducing ends. As observed in previous investigations, the C-1 region of the 13C-NMR of these heteropolysaccharides are typical of some lichens species, and can be used as fingerprints in chemotaxonomy. However, in despite of the general structure in common, the substitution level of this structure and their content of mannose is higher than of the others galactomannans obtained of lichenized fungi contained the green alga of the genus Trebouxia. [Copyright &y& Elsevier]

Abstract: The gum exudate polysaccharide from the trunk of nectarine (PPNEC) was compared with that of peach, being composed of Ara, Xyl, Man, Gal, and uronic acids in 37:13:2:42:6 molar ratio and had M w 3.93×106 gmol−1, compared with 5.61×106 gmol−1 for peach gum polysaccharide. Methylation analysis of PPNEC indicated a highly branched structure with relatively high amounts of di- (16%) and tri-O-substituted (9%) Galp units and nonreducing end-units of Araf (26%) and Xylp (17%). Combination with 13C NMR data, showed the presence of α-l-Araf (nonreducing end, 3-O-, 5-O-, and 2,5-di-O-subst.), β-l-Arap (4-O- and 2,4-di-O-subst.), β-d-Galp (3-O-, 2,3-di-O-, 3,6-di-O-, and 3,4,6-tri-O-subst.), and α- and/or β-d-Xylp nonreducing end-units. A signal appeared from 4-O-Me-α-d-GlcpA units. PPNEC had structures similar to those of polysaccharide from peach tree gum, although in different proportions and with a lower M w. [Copyright &y& Elsevier]