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We report a rapid purification method using one-step chromatography of SVSP Rhombeobin (LMR-47) from Lachesis muta rhombeata venom and its procoagulant activities and effects on platelet aggregation. The venom was fractionated by a single chromatographic step in RP-HPLC on a C8 Discovery BIO Wide Pore, showing high degree of molecular homogeneity with molecular mass of 47035.49 Da. Rhombeobin showed amidolytic activity upon BApNA, with a broad optimum pH (7-10) and was stable in solution up to 60°C. The amidolytic activity was inhibited by serine proteinase inhibitors and reducing agents, but not chelating agents. Rhombeobin showed high coagulant activity on mice plasma and bovine fibrinogen. The deduced amino acid sequence of Rhombeobin showed homology with other SVSPs, especially with LM-TL (L. m. muta) and Gyroxin (C. d. terrificus). Rhombeobin acts, in vitro, as a strong procoagulant enzyme on mice citrated plasma, shortening the APTT and PT tests in adosedependent manner. The protein showed, "ex vivo", a strong defibrinogenating effect with 1 μg/animal. Lower doses activated the intrinsic and extrinsic coagulation pathways and impaired the platelet aggregation induced by ADP. Thus, this is the first report of a venom component that produces a venom-induced consumptive coagulopathy (VICC). [ABSTRACT FROM AUTHOR]

Casearia sylvestris Sw., also known as "guaçatonga," is a medicinal plant with broad use in South America. Among the popular applications attributed to this plant are anti-inflammatory, anticancer, antimicrobial, and antiulcer activities. Despite the broad popular use of this plant as a phytopharmaceutical agent, there are few studies about the antimicrobial potential of guaçatonga. In this work, we have studied the antimicrobial potential of an ethanol extract obtained from C. sylvestris leaves against three yeasts, two filamentous fungus, six Gram-negative bacteria, and two Gram-positive bacteria. Through two chromatographic steps using a Sephadex LH-20 column and RP-HPLC, we isolated and characterized two derived compounds of gallic acid: isobutyl gallate-3,5-dimethyl ether (IGDE) and methyl gallate-3,5-dimethyl ether (MGDE). Both compounds showed antimicrobial activity. IGDE was much more efficient than MGDE in inhibiting yeasts (Candida albicans, Candida tropicalis, and Candida guilliermondii) and Gram-positive bacteria (Enterococcus faecalis and Staphylococcus aureus). This fact is probably associated with the higher hydrophobicity degree of IDGE compared with MGDE. [ABSTRACT FROM AUTHOR]

A lectin with a high affinity for glucose/mannose was isolated from Annona muricata seeds (Annonaceae) by gel filtration chromatography on Sephacryl S-200, ion exchange chromatography on a DEAE SP-5 PW column, and molecular exclusion on a Protein Pak Glass 300 SW column. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (PAGE) yielded two protein bands of approximately 14 kDa and 22 kDa. However, only one band was seen in native PAGE. The Mr of the lectin estimated by fast-performance liquid chromatography-gel filtration on Superdex 75 was 22 kDa. The lectin was a glycoprotein with 8% carbohydrate (neutral sugar) and required divalent metal cations (Ca2+, Mg2+, and Mn2+) for full activity. Amino acid analysis revealed a large content of Glx, Gly, Phe, and Lys. The lectin agglutinated dog, chicken, horse, goose, and human erythrocytes and inhibited the growth of the fungi Fusarium oxysporum, Fusarium solani, and Colletotrichum musae. [ABSTRACT FROM AUTHOR]