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Polysaccharides from P. eryngii mushroom were selectively extracted using low-cost technologies (water at different conditions of temperature and pressure). Mannogalactan was the main polysaccharide in cold-water extracted fraction (CWEF), while a linear (1→6)-ß-d-glucan was the main polymer in hot-water extracted fraction (HWEF). Autoclave-extracted fraction (AEF) contained a mixture of at least four different α- and ß-glucans. The report of linear (1→6)-ß-glucan and linear (1→3)-ß-glucan is a new finding for P. eryngii fruiting bodies. The immunostimulatory properties of the fractions on THP-1 macrophages were studied. All fractions at 50, 250 and 500 µg/mL were not cytotoxic and produced different stimulus on NO, IL-1ß and IL-10 secretion by the cells. Thus, our results showed that it is possible to concentrate different P. eryngii polysaccharides in selected fractions using a simple and low-cost procedure. Since biological effects depends on the polysaccharide structure, this technique allows the obtainment of fractions with distinct immunomodulatory activities.

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World fisheries and aquaculture production totaled 167 million tons in 2014. This high fish production generates a lot of waste that could be used as raw material for extraction of substances of pharmacological interest. In this work, we extract and characterize glycosaminoglycans (GAGs) present in the viscera of Nile tilapia (Oreochromis niloticus) and Pacu (Piaractus mesopotamicus), which are among the most vastly produced fishes in inland aquaculture in Brazil. Moreover, the anticoagulant activity of the GAGs fractions was evaluated. GAGs were obtained from total defatted viscera, after proteolysis, precipitation with ethanol, anion exchange chromatography and treatment with chondroitinase. Chondroitin sulfate (CS), dermatan sulfate (DS) and heparan sulfate (HS) were identified by agarose gel electrophoresis and NMR analyses. CS, DS and HS were identified in equivalent fractions obtained from both fishes, and all GAGs fractions showed anticoagulant activity.

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Croton cajucara Benth. is a medicinal plant popularly used in the Brazilian Amazonia, where it is known as sacaca, being consumed as tea, decoction or infusion of the leaves and stem bark. From a decoction of the leaves, a comprehensive phytochemical analysis was developed by liquid chromatography-mass spectrometry. Many compounds were identified for the first time in C. cajucara, such as O-glycosides of kaempferol and quercetin, flavonoid-C-glycosides, tannins and cinnamic acid derivatives. These compounds were fractionated by polarity and assayed for their anti-inflammatory activity, using a model of mice edema, induced by an intraplantar injection of carrageenan. All fractions exhibited anti-inflammatory properties.

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The polysaccharide compositions of primary and secondary cell walls of members of the family Arecaceae in the commelinid clade of monocotyledonous plants have previously been found to be distinguishable from other commelinid families, and to be more similar to those of non-commelinids. However, few studies have been conducted. We aimed to extract and characterize the main cell-wall polysaccharides in the fruit pulp of tucumã (Astrocaryum aculeatum), a member of Arecaceae family. Hemicellulosic polysaccharides extracted by alkali from the fruit pulp were present in greater proportions (6.4% yield) than water-extracted ones (3.0% yield). Thus, the former was analyzed using monosaccharide composition, methylation, molecular weight determination and 13C-NMR data. The tucumã alkaline extract presented a highly ramified acidic galactoarabinoxylan (53.7%), a linear (1 â†’ 5)-linked α-L-arabinan (27.8%), a low branched glucuronoxylan (14.1%) and small portions of a xyloglucan (4.4%). The major polysaccharide found in A. aculeatum (acidic galactoarabinoxylan) is similar to those found in other commelinid plants such as grasses and cereals.

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Electroactive hydrogels were prepared using commercial citric pectin, either raw (PC) or purified through dialysis (dPC), and chemically synthesized polypyrrole (PPy). 1H NMR analyses showed that PC is a low methoxyl pectin (degree of methoxylation, DM=46%) and dPC is a high methoxyl pectin (DM=77%). The pyrrole polymerization was monitored through UV-vis spectroscopy and both samples were observed to be good stabilizers for PPy in aqueous medium. The dispersions were used to prepare the hydrogels h-PC-PPy and h-dPC-PPy. The hydrogel h-dPC-PPy has a higher swelling index (SI≈25%) at pH 1.2 than the hydrogel h-PC-PPy (SI≈7%). Contrastingly, at pH 6.8 both hydrogels lost their mechanical integrity. Raman spectroscopy revealed that PPy is more oxidized in h-PC-PPy. Nevertheless, both hydrogels are electroactive and therefore can be considered for applications in which the control of the degree of swelling is desired.

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Croton cajucara Benth. is a tree from the Amazon Forest, where it is known as sacaca. Its leaves and barks are used in medicinal preparations to treat different diseases, including gastric ulcers. The crude polysaccharide fraction (CCP), obtained from the hot aqueous extract of C. cajucara leaves, was able to promote gastroprotection on an ethanol induced gastric ulcer model. Therefore, a bioguided fractionation was performed to isolate the active polysaccharide fraction. After freezing-thawing, ultrafiltration and dialyses at 100, 50, and 25kDa cut-off membranes, fraction 25R was obtained. It contained glucose, galactose, rhamnose, arabinose, galacturonic acid and mannose in a 7:5:5:3:1:1 molar ratio approximately, and had a Mw of 42,840g/mol. Methylation analysis and NMR spectroscopy indicated that 25R is a very complex polysaccharide fraction containing type I rhamnogalacturonan, arabinan, type I arabinogalactan, type II arabinogalactan, rhamnan, starch and mannan. It was able to reduce ethanol-induced gastric ulcers in rats, through preservation of mucus and GSH levels.

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The chemical features of xylan largely determine its physical and biological properties and its use in the industry. In this work, we describe the occurrence, purification and partial characterization of a xylan in edible açaí berries (Euterpe oleraceae), using a fairly simple and inexpensive method of purification from alkaline açaí extract. A mainly linear (1→4)-ß-d-xylan was found as the majority (70%) of alkali extract and 4.2% of the dry matter açaí pulp. This represents the biggest source of xylan found so far in a fruit pulp and could be suitable for applications in the industry and biomedical field.

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Low molecular weight heparin, which is generally obtained by chemical and enzymatic depolymerization of unfractionated heparin, has high bioavailability and can be subcutaneously injected. The aim of the present investigation was to fractionate bovine heparin using a physical method (ultrafiltration through a 10kDa cut-off membrane), avoiding structural modifications that can be caused by chemical or enzymatic treatments. Two fractions with different molecular weights were obtained: the first had an intermediate molecular weight (B-IMWH; Mn=9587Da) and the other had a high molecular weight (B-HMWH; 22,396Da). B-IMWH and B-HMWH have anticoagulant activity of 103 and 154IU/mg respectively, which could be inhibited by protamine. Both fractions inhibited α-thrombin and factor Xa in vitro and showed antithrombotic effect in vivo. Moreover, ex vivo aPTT assay demonstrated that B-IMWH is absorbed by subcutaneous route. The results showed that ultrafiltration can be used to obtain two bovine heparin fractions, which differ on their molecular weights, structural components, anticoagulant potency, and administration routes.

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Açaí berries (Euterpe oleracea) are greatly consumed in Brazil and exported to other countries as a nutritional supplement, due to health benefits attributed to its consumption. However, the complete chemical structure of bioactive polysaccharides was not fully elucidated yet. In this work, we characterize pectic polysaccharides from açaí berries through monosaccharide composition, HPSEC, methylation and 13C and 1H/13C HSQC-DEPT-NMR analyses. A highly methoxylated homogalacturonan with a DM of 88% and Mw of 22kDa together with small amounts of a mannoglucan were found. Moreover, a type II arabinogalactan (Mw=45kDa) containing a backbone with high portions of 6-O-linked and 3,6-O-linked Galp chains rather than 3-O-linked Galp was also isolated and structurally characterized. The type II arabinogalactan was found as a side chain of a type I rhamnogalacturonan. These findings contribute to correlate the fine chemical structure with the previously reported action of açaí polysaccharides on innate immune response. Moreover, from the taxonomic point of view, the results bring new information about polysaccharide composition of primary cell walls of palms (Arecaceae), that despite being commelinid monocots, have a distinct cell wall composition.

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The plant Arctium lappa L. is popularly used to relieve symptoms of inflammatory disorders. A crude polysaccharide fraction (SAA) resulting of aqueous extraction of A. lappa leaves showed a dose dependent anti-edematogenic activity on carrageenan-induced paw edema, which persisted for up to 48h. Sequential fractionation by ultrafiltration at 50kDa and 30kDa cut-off membranes yielded three fractions, namely RF50, RF30, and EF30. All these maintained the anti-edematogenic effect, but RF30 showed a more potent action, inhibiting 57% of the paw edema at a dose of 4.9mg/kg. The polysaccharide RF30 contained galacturonic acid, galactose, arabinose, rhamnose, glucose, and mannose in a 7:4:2:1:2:1 ratio and had a Mw of 91,000g/mol. Methylation analysis and NMR spectroscopy indicated that RF30 is mainly constituted by a type I rhamnogalacturonan branched by side chains of types I and II arabinogalactans, and arabinan.

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