106 resultados para Extrato de jerivá
Resumo:
Sulfated polysaccharides (PS) are biomolecules with a great biotechnological potential. There are few data about PS from high plants. In addition, pharmacological activities of PS from plants have not been carrying out. The aim of this work was extract PS from the angiosperm Halodule wrightii and study their anticoagulant and antioxidant activities. Histological analysis showed the presence of the PS manly in the roots. A polysaccharide-rich extract was obtained from H. wrightii by proteolysis followed by methanol and TCA precipitation. Chemical, infra-red analysis and agarose gel electrophoresis in 1.3 diaminopropane acetate buffer confirmed the presence of sulfated polysaccharides made by glucose, galactose, xylose and sulfate residues in the proportion 1: 0,9: 1: 1. In addition polyacrilamide electrophoresis have shown that extract is mainly compose by 11kDa sulfated polysaccharides. Pharmacological analysis have shown total antioxidant capacity (CAT) that resulted in 15,21 μg for equivalent of ascorbic acid, scavenging activity of the DPPH radical with 41,36 % of scavenging, activity of reducing power with the maximum of 0,290 nm (50 % of vitamin C activity) and scavenging activity superoxide radical (O2-) with a maximum of 32,23 %. Chelating activity of metal less than 4% and scavenging activity of the radical hydroxyl (OH-) less than 2%. Time of activated partial tromboplastin (aPTT) doubling the time of coagulation from 20μg of and protrombin time (PT) was not present. The data indicate that PS from Halodule wrightii could be considered for future applications in medicine, food production or cosmetic industry
Resumo:
Sulfated polysaccharides (PS) are biomolecules with a great biotechnological potential. There are few data about PS from high plants. In addition, pharmacological activities of PS from plants have not been carrying out. The aim of this work was extract PS from the angiosperm Halodule wrightii and study their anticoagulant and antioxidant activities. Histological analysis showed the presence of the PS manly in the roots. A polysaccharide-rich extract was obtained from H. wrightii by proteolysis followed by methanol and TCA precipitation. Chemical, infra-red analysis and agarose gel electrophoresis in 1.3 diaminopropane acetate buffer confirmed the presence of sulfated polysaccharides made by glucose, galactose, xylose and sulfate residues in the proportion 1: 0,9: 1: 1. In addition polyacrilamide electrophoresis have shown that extract is mainly compose by 11kDa sulfated polysaccharides. Pharmacological analysis have shown total antioxidant capacity (CAT) that resulted in 15,21 μg for equivalent of ascorbic acid, scavenging activity of the DPPH radical with 41,36 % of scavenging, activity of reducing power with the maximum of 0,290 nm (50 % of vitamin C activity) and scavenging activity superoxide radical (O2-) with a maximum of 32,23 %. Chelating activity of metal less than 4% and scavenging activity of the radical hydroxyl (OH-) less than 2%. Time of activated partial tromboplastin (aPTT) doubling the time of coagulation from 20μg of and protrombin time (PT) was not present. The data indicate that PS from Halodule wrightii could be considered for future applications in medicine, food production or cosmetic industry
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The incidence of toxic cyanobacterial blooms is one of the important consequences of eutrophication in aquatic ecosystems. It is a very common phenomenon in reservoirs and shrimp ponds in the State of Rio Grande do Norte (RN), Brazil. Cyanobacterias produce toxins which can affect aquatic organisms and men trough the food chain. Aiming to contribute to the studies of cyanobacterias in RN, we propose: a) to evaluate the toxicity of isolated cyanobacterias in important fresh-water environments; and b) to verify the effects of both natural and cultured blooms occurred in reservoirs for human supply and in the cladoceran Ceriodaphnia silvestrii. This study was carried out using samples of natural blooms occurred between March and October of 2004 in Gargalheiras Dam (08º L e 39º W), in July of 2004 in Armando Ribeiro Gonçalves Dam (06o S e 37o W) and in commercial shrimp ponds (Litopenaeus vannamei) located in fresh-water environments. The samples were collected with plankton net (20µm.) for identification, isolation and obtaining of phytoplanktonic biomass for liophilization and later toxicity bioassays. The toxicity of cultured samples and natural blooms was investigated through bioassays in Swiss mice. Quantification of cyanobacteria in samples was conducted following the Ütermol method, with 300mL samples fixed with lugol. The toxicity test with Ceriodaphnia silvestrii followed ABNT, 2001 recommendations, and were accomplished with natural hepatotoxic bloom s samples and cultured samples of both non-toxic and neurotoxic C. raciborskii. In this test, five newborns, aged between 6 and 24 hours, were exposed to different concentrations (0 a 800 mg.L-1) of crude cyanobacterial extracts during 24 and 48 hours. Three replicates were used per treatment. The pH, temperature and dissolved oxygen at the beginning and after 24 and 48hours from the test were measured. We estimated the CL50 through the Trimmed Spearman-Karber method. The blooms were constituted by Microcystis panniformis, M. aeruginosa, Anabaena circinalis, Cylindrospermopsis raciborskii and Planktothrix agardhii, producers of mycrocistin-LR confirmed with HPLC analysis. Samples of hepatotoxic blooms registered toxinogenic potential for C. silvestrii, with CL50-24h value of 47.48 mg.L-1 and CL5048h of 38.15 mg.L-1 for GARG samples in march/2005; CL50-24h of 113,13 mg.L-1 and CL5048h of 88,24 mg.L-1 for ARG July/2004; CL50-24h of 300.39 mg.L-1 and CL50-48h of 149.89 mg.L-1 for GARG October/2005. For cultured samples, values of CL50-24h and CL50-48h for C. raciborskii toxic strains were 228.05 and 120.28 mg.L-1, respectively. There was no mortality of C. silvestrii during the tests with non-toxic C. raciborskii strain. The toxicity test with C. silvestrii presented good sensitivity degree to cyanotoxins. The toxicity of natural hepatotoxic blooms samples (microcystins) and cultured neurotoxic saxitoxins producer samples analyzed in this study give us strong indications of that toxin s influence on the zooplanktonic community structure in tropical aquatic environments. Eleven cyanobacteria strains were isolated, representing 6 species: Anabaenopsis sp., Cylindrospermopsis raciborskii, Chroococcus sp., Microcystis panniformis, Geitlerinema unigranulatum e Planktothrix agardhii. None presented toxicity in Swiss mice. The strains were catalogued and deposited in the Laboratório de Ecologia e Toxicologia de Organismos Aquáticos (LETMA), in UFRN, and will be utilized in ecotoxicológical and ecophysiological studies, aiming to clarify the causes and control of cyanobacterial blooms in aquatic environments in RN. This state s reservoirs must receive broader attention from the authorities, considering the constant blooms occurring in waters used for human consumption
Resumo:
Four different sponge species were screened using Ouchterlony agarose gel and immunodiffusion tests to identify cross-reactivity with the polyclonal antibody IgG anti-deglicosilated CvL, a lectin from Cliona varians. Crude extract from the sponge Cinachyrella apion showed cross-reactivity and also a strong haemmaglutinating activity towards human erythrocytes of all ABO groups. Thus, it was submitted to acetone fractionation, IgG anti-deglicosilated CvL Sepharose affinity chromatography, and Fast Protein Liquid Chromatography (FPLC-AKTA) gel filtration on a Superose 6 10 300 column to purify a novel lectin. C. apion lectin (CaL) agglutinated all types of human erythrocytes with preference for papainized type A and O erythrocytes. The haemagglutinating activity is independent of Ca2+, Mg2+ and Mn2+ ions, and it was strongly inhibited by the disaccharide D-lactose, up to a minimum concentration of 6.25 mM. CaL molecular mass determined by FPLC-AKTA gel filtration on a Superose 12 10 300 column and SDS gel electrophoresis was approximately 124 kDa, consisting of eight subunits of 15.5 kDa, assembled by hydrophobic interactions. The lectin was relatively heat- and pH-stable. Leishmania chagasi romastigotes were agglutinated by CaL, indicating that lactose receptors could be presented in this parasite stage. These findings are indicative of the physiological defense roles of CaL and its possible use in the antibiosis of pathogenic protozoa
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This work studies the involved enzymatic way in the metabolism of glycosaminoglycans sulfateds in the mollusc Pomacea sp. Had been identified endoglycosidases and exoglycosidases in the enzymatic extract of the mollusc Pomacea sp by means of hydrolysis activity in condroitim sulphate of whale cartilage and of the p-Nitrofenil-β-glucuronide, respectively. The enzymatic extracts qere obtained of Pomacea sp. being used of 0.1 sodium acetate buffer, pH 5.0 and later centrifugated the 8,000 x g and the presents proteins in the sobrenadante were submitted to the fractionament with two crescents ammonium sulphate concentrations, the visualized activity biggest in the F2 fraction (50-80%). The β-glucuronidase (F3) was isolated in gel chromatography filtration Biogel 1.5m, the purification degree was ratified in Chromatography Liquid of high efficiency (HPLC). The enzyme was purificated 6.362,5 times with 35,6% yield. The β -glucuronidase isolated in this work showed a molecular mass of 100 kDa, determined for eletroforese in poliacrilamida gel . The determination of the ideal kinetic parameters for the catalysis of the p-nitrofenil- β -glucuronide for β-glucuronidase, showed excellent activity in pH 5,0 and temperature 65ºC for 6 hours and apparent Km of 72 x 10-2 mM. It is necessary for the total degradation of 3mM of p-N-β-glucoronide, the amount of 1,2μg of ss-glucuronidase. The BaCl2 increased the activity of ss-glucuronidase, and the activity was inhibited completely by the composites SDS and NaH2PO4
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A 140,0 kDa lectin was purified and characterized from the mushroom Clavaria cristata. The purification procedures from the crude extract of the mushroom comprised gel filtration chromatography on Sephacryl s200 and ion exchange on Resource Q column. The purified lectin agglutinated all types of human erythrocytes with preference for trypsinized type O erythrocytes. The haemagglutinating activity is dependent of Ca 2+ ions and was strongly inhibited by the glycoprotein bovine submaxillary mucin (BSM) up to the concentration of 0, 125 mg/mL. The C. cristata lectin (CcL) was stable in the pH range of 2,5-11,5 and termostable up to 80 °C. CcL molecular mass determined by gel filtration on a Superose 6 10 300 column was approximately 140,3 kDa. SDS polyacrilamide gel electrophoresis revealed a single band with a molecular mass of approximately 14,5 kDa, when the lectin was heated at 100 ⁰C in the presence or absence of β-mercaptoethanol. CcL induced activation of murine peritoneal macrophages in vitro resulting in the release of nitric oxide (NO), reaching the maximum production at 24 h. In experimental paw oedema model in mice, CcL showed proinflammatory activity being able to induce oedema formation. Cell viability of HepG2, MDA 435 e 3T3 cell lines was examined after 72 h of incubation with CcL in different concentrations (0,5-50 μg/mL). CcL inhibited HepG2 cells growth with an IC50 value of 50 μg/mL. In the present work, the observed immunomodulatory and antiproliferative effects indicate CcL as a possible immunomodulator compound, interfering in the macrophages immune response, taking possible anti-parasitic, anti-tumoral effects or diagnostic and/or therapeutic
Resumo:
The present study examines the chemical composition and their effects on free radicals, inflammation, angiogenesis, coagulation, VEGF effects and cellular proliferation of a polysaccharides from alga Sargassum vulgare. The sulfated polysaccharide was extracted from brown seaweed by proteolysis with enzymes maxataze. The presence of proteins and sugars were observed in crude polysaccharides. Fractionation of this crude extract was made with growing concentration of acetone (0.3-1.5 v) and produced four groups of polysaccharides. Anionic polysaccharides from brown seaweed Sargassum vulgare, SV1and PSV1 were fractionated (SV1) and purified (PSV1), and displayed with high total sugars and sulfate content and very low level of protein. This fucan SV1 contains low levels of protein and high carbohydrate and sulfate content. This polysaccharides prolonged activated partial thromboplastin time (aPTT) at 50 μg (>240 s). SV1 was found to have no effect on prothrombin time (PT), corresponding to the extrinsic pathway of coagulation. SV1 exhibits high antithrombotic action in vivo, with a concentration ten times higher than heparin. Polysaccharides from S. vulgare promoted direct inhibition enzymatic activity of thrombin and stimulated enzymatic activity of FXa. SV1 showed optimal inhibitory activity of thrombin (50.2±0.28%) at a concentration of 25 μg/mL. Its antioxidant action on scavenging radicals by DPPH was (22%), indicating the polymer has no cytotoxic action (hemolytic) on ABO and Rh blood types in different erythrocyte groups and displays strong anti-inflammatory action on all concentrations tested in the carrageenan-induced paw edema model, demonstrated by reduced edema and cellular infiltration. Angiogenesis is a dynamic process of proliferation and differentiation. It requires endothelial proliferation, migration, and tube formation. In this context, endothelial cells are a preferred target for several studies and therapies. The antiangiogenic efficacy of polysaccharides was examined in vivo in the chick chorioallantoic membrane (CAM) model by using fertilized eggs. Decreases in the density of the capillaries were assessed and scored. The results showed that SV1 and PSV1 have an inhibitory effect on angiogenesis. These results were also confirmed by inhibition tubulogenesis in rabbit aorta endothelial cell (RAEC) in matrigel. These compounds were assessed in Apoptosis assay (Annexin V - FITC / PI) and cell viability by MTT assay of RAEC. These polysaccharides do not affect the viability and do not have apoptotic or necrotic action. RAEC cell when incubated with SV1 and PSV1showed inhibition of VEGF secretion, observed when compounds were incubated at 25, 50 and 100 μg/μL. The VEGF secretion with the RAEC cell line for 24 h, was more effective for PSV1 at 50 μg/μL(71.4%) than SV1 100 μg/μL (75.9%). SV1 and PSV1 had an antiproliferative action (47%) against tumor cell line HeLa. Our results indicate that these sulfated polysaccharides have antiangiogenic and antitumoral actions
Resumo:
In the present study, extracts rich-sulfated polysaccharides were obtained from three different species of Dictyotales (a class of brown macroalgae): Canistrocarpus cervicornis, Dictyota mertensii and Dictyopteris delicatula and their anticoagulant and antioxidant activities were evaluated. All extracts showed anticoagulant activity on aPTT assay, but not on PT assay. Extracts also exhibited total antioxidant activity, superoxide radical scavenging capacity and ferric chelating property. The extract from C. cervicornis showed the best results and was choose to have their sulfated polysaccharides fractioned and subsequently analysed. Thus, six fractions (CC-0.3, CC-0.5, CC-0.7, CC-1.0, CC-1.2 and CC-2.0) were obtained by proteolysis followed by sequential acetone precipitation. Agarose gel eletrophoresis stained with blue toluidine, confirmed the presence of sulfated polysaccharides in all fractions. Chemical analyses showed that all fractions presented heterofucans mainly constitued by fucose, galactose, glucuronic acid and sulfate. Any fraction changed the PT. However, all fractions were able to double the aPTT on a dose-dependent manner. CC- 0.3, CC-0.5, CC-0.7 and CC-1.0 needed only 0.100 mg/mL to double the aPTT, result only 1.25 times higher than the Clexane® (0.080 mg/mL), a commercial low molecular heparin. The heterofucans presented appreciable total antioxidant capacity, low capacity on scavenging hydroxyl radical and good efficiency on scavenging superoxide radicals (except CC-1.0). CC-1.2 showed 43.1 % on superoxide radical scavenging. This result was higher than that showed by the same concentration of gallic acid (41.8 %), a known antioxidant. Furthermore, the heterofucans showed excelent activity on ferrous chelating activity (except CC-0.3). CC-0.5, CC-0.7 and CC-1.0 showed the highest activities with 47.0 % of ferrous chelating activity, a result 2.0 times lesser than that exhibited by the same concentration of EDTA. These results clearly indicated the beneficial effects of heterofucans extracted from C. cervicornis as potential anticoagulant and antioxidant agents. However additional steps of purification, structural studies, besides in vivo experiments are needed for these fucans may be used as therapeutic agents
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The species of the genus Marsdenia, Apocynaceae, are widely used in folk medicine of several countries. In Brazil is found several species belonging to this genus. The in vitro antioxidant, anticoagulant and antiproliferative activities were evaluated to aqueous extracts of stalk, leaf and root of Marsdenia megalantha. In the total antioxidant capacity assay (expressed as ascorbic acid equivalents) the stalk extract showed 76.0 mg/g, while leaf and root extracts 141.3 mg/g and 57.0 mg/g, respectively. The stalk and leaf extracts showed chelating activity around 40% at 1.5 mg/mL, while root extract, at the same concentration showed, 17%. Only the leaf extract showed a significant ability in superoxide scavenging (80% at 0.8 mg/mL). Any extract was able in scavenge hydroxyl, as well anticoagulant activity. The antiproliferative activity of the extracts was evaluated against HeLa tumor cell line. The extracts inhibited in a dose-dependent manner the cell growth. However, the leaf extract showed 80% of inhibition at 1.0 mg/mL, while stalk and root extracts inhibited 63% and 30%, respectively. To assess the mechanism of cell death caused by the leaf extract in HeLa, was performed flow cytometry and western blot. The results show that leaf extract induces cell death by apoptosis through an activation caspase-independent pathway. These data indicate that stalk and leaf extracts obtained have potential to be used as antioxidants and anticancer drugs
Resumo:
The acquisition of oligosaccharides from chitosan has been the subject of several studies in the pharmaceutical, biochemical, food and medical due to functional properties of these compounds. This study aimed to boost its production of chitooligosaccharides (COS) through the optimization of production and characterization of chitosanolytic enzymes secreted by microorganisms Paenibacillus chitinolyticus and Paenibacillus ehimensis, and evaluating the antioxidant potential of the products obtained. In the process of optimizing the production of chitosanase were employed strategies Fractional Factorial Experimental Design and Central Composite Rotatable Design. The results identified the chitosan, peptone and yeast extract as the components that influenced the production of chitosanase by these microorganisms. With the optimization of the culture media was possible to obtain an increase of approximately 8.1 times (from 0.043 to 0.35 U.mL U.mL-1) and 7.6 times (from 0.08 U.mL-1 to 0.61 U.mL-1) in the enzymatic activity of chitosanase produced by P. chitinolyticus and P. ehimensis respectively. Enzyme complexes showed high stability in temperature ranges between 30º and 55º C and pH between 5.0 and 9.0. Has seen the share of organic solvents, divalent ions and other chemical agents on the activity of these enzymes, demonstrating high stability of these crude complexes and dependence of Mn2+. The COS generated showed the ability of DPPH radical scavenging activity, reaching a maximum rate of scavenging of 61% and 39% when they were produced with enzymes of P. ehimensis and P. chitinolyticus respectively. The use of these enzymes in raw form might facilitate its use for industrial applications
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Compounds derived from fungi has been the subject of many studies in order to broaden the knowledge of their bioactive potential. Polysaccharides from Caripia montagnei have been described to possess anti-inflammatory and antioxidant properties. In this study, glucans extracted from Caripia montagnei mushroom were chemically characterized and their effects evaluated at different doses and intervals of treatment. It was also described their action on colonic injury in the model of colitis induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS), and its action on cells of the human colon carcinoma (HT-29). Compounds extracted of C. montagnei contain high level of carbohydrates (96%), low content of phenolic compounds (1.5%) and low contamination with proteins (2.5%). The (FT-IR) and (NMR) analysis showed that polysaccharides from this species of mushroom are composed of α- and β-glucans. The colonic damage was evaluated by macroscopic, histological, biochemical and immunologic analyses. The results showed a reduction of colonic lesions in all groups treated with the glucans of Caripia montagnei (GCM). GCM significantly reduced the levels of IL-6 (50 and 75 mg/kg, p < 0.05), a major inflammatory cytokine. Biochemical analyses showed that such glucans acted on reducing levels of alkaline phosphatase (75 mg/kg, p < 0.01), nitric oxide (p < 0.001), and myeloperoxidase (p < 0.001). These results were confirmed microscopically by the reduction of cellular infiltration. The increase of catalase activity suggest a protective effect of GCM on colonic tissue, confirming their anti-inflammatory potential. GCM displayed cytostatic activity against HT-29 cells, causing accumulation of cells in G1 phase, blocking the cycle cell progression. Those glucans also showed ability to modulate the adhesion of HT-29 cells to Matrigel® and reduced the oxidative stress. The antiproliferative activity against HT-29 cells displayed by GCM (p <0.001) can be attributed to its cytostatic activity and induction of apoptosis by GCM
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Chitinases are enzymes involved in degradation of chitin and are present in a range of organisms, including those that do not contain chitin, such as bacteria, viruses, plants and animals, and play important physiological and ecological roles. Chitin is hydrolyzed by a chitinolytic system classified as: endo-chitinases, exo-chitinases and N-acetyl-b-D-glucosaminidases. In this study a Litochitinase1 extracted from the cephalotorax of the shrimp Litopenaeus Schmitt was purified 987.32 times using ionexchange chromatography DEAE-Biogel and molecular exclusion Sephacryl S-200. These enzyme presented a molecular mass of about 28.5 kDa. The results, after kinetic assay with the Litochitinase1 using as substrate p-nitrophenyl-N-acetyl-b-Dglucosaminideo, showed apparent Km of 0.51 mM, optimal activity at pH ranging from 5.0 to 6.0, optimum temperature at 55°C and stability when pre-incubated at temperatures of 25, 37, 45, 50 and 55°C. The enzyme showed a range of stability at pH 4.0 to 5.5. HgCl2 inhibited Litochitinase1 while MgCl2 enhances its activity. Antimicrobial tests showed that Litochitinase1 present activity against gram-negative bacterium Escherichia coli in the 800 μg/mL concentration. The larvicidal activity against Aedes aegypti was investigated using crude extracts, F-III (50-80%) and Litochitinase1 at 24 and 48 hours. The results showed larvicidal activity in all these samples with EC50 values of 6.59 mg/mL for crude extract, 5.36 mg/mL for F-III and 0.71 mg/mL for Litochitinase1 at 24 hours and 3.22 and 0.49 mg/mL for the F-III and Litochitinase1 at 48 hours, respectively. Other experiments confirmed the presence of chitin in the midgut of Aedes aegypti larvae, which may be suffering the action of Litochitinase1 killing the larvae, but also the absence of contaminating proteins as serine proteinase inhibitors and lectins in the crude extract, F-III and Litochitinase1, indicating that the death of the larvae is by action of the Litochitinase1. We also observed that the enzymes extracted from intestinal homogenate of the larvae no have activity on Litochitinase1. These results indicate that the enzyme can be used as an alternative to control of infections caused by Escherichia coli and reducing the infestation of the mosquito vector of dengue.
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This study examines the physical and chemical composition and the pharmacological effects of brown seaweed FRF 0.8 Lobophora variegata. Fractionation of the crude extract was done with the concentration of 0.8 volumes of acetone, obtaining the FRF 0.8. The physicochemical characterization showed that it was a fucana sulfated. Anti-inflammatory activity was assessed by paw edema model by the high rates of inhibition of the edema and the best results were in the fourth hour after induction (100 ± 1.4% at the dose of 75 mg / kg) and by the strong inhibitory activity of the enzyme myeloperoxidase (91.45% at the dose of 25 mg / kg). The hepataproteção was demonstrated by measurements of enzymatic and metabolic parameters indicative of liver damage, such as bilirubin (reduction in 68.81%, 70.68% and 68.21% for bilirubin total, direct and indirect, respectively at a dose of 75 mg / kg), ALT, AST and γ-GT (decrease of 76.93%, 44.58% and 50% respectively at a dose of 75 mg / kg) by analysis of histological slides of liver tissue, confirming that hepatoprotective effect the polymers of carbohydrates, showing a reduction in tissue damage caused by CCl4 and the inhibition of the enzyme complex of cytochrome P 450 (increasing sleep time in 54.6% and reducing the latency time in 71.43%). The effectiveness of the FRF 0.8 angiogenesis was examined in chorioallantoic membrane (CAM) of fertilized eggs, with the density of capillaries evaluated and scored, showing an effect proangigênico at all concentrations tested FRF (10 mg- 1000 mg). The FRF showed antioxidant activity on free radicals (by inhibiting Superoxide Radical in 55.62 ± 2.10%, Lipid Peroxidation in 100.15 ± 0.01%, Hydroxyl Radical in 41.84 ± 0.001% and 71.47 Peroxide in ± 2.69% at concentration of 0.62 mg / mL). The anticoagulant activity was observed with prolongation of activated partial thromboplastin time (aPTT) at 50 mg (> 240 s), showing that its action occurs in the intrinsic pathway of the coagulation cascade. Thus, our results indicate that these sulfated polysaccharides are an important pharmacological target
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Lectin obtained from the marine sponge Tedania ignis was purified and characterized by extraction of soluble proteins (crude extract) in 50mM Borax, pH 7.5. The purification procedure was carried out by crude extract precipitation with ammonium sulfate 30% (FI). The precipitated was resuspended in the same buffer and fractionated with acetone 1.0 volume (F1.0). A lectin was purified from this specific fraction by using an affinity chromatography Sepharose 6B. This lectin preferentially agglutinated human erythrocytes from B type previously treated with papain enzyme. The hemagglutinating activity lectin was dependent of divalent Mn2+ cation and was inhibited by the carbohydrates galactose, xylose and fructose. SDS-PAGE analysis indicated a molecular mass of the lectin around 45 kDa. This protein showed stability until 40°C for 1 h. Further, it showed activity between pH 2.5 and 11.5, with an enhanced activity at pH 7.5. Leishmania chagasi promastigotes stained with Coomassie brilliant blue R-250 were agglutinated by F1,0 and in the presence of galactose this interaction was abolished. These results show that this lectin could be implicated in defense procedures and it will can be used as biological tools in studies with this protozoon
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