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Skin secretions of frogs have a high chemical complexity. They have diverse types of biomolecules, such as proteins, peptides, biogenic amines, and alkaloids. These compounds protect amphibians' skin against growth of bacteria, fungi, and protozoa and participate in defense system against attack from predators. Therewith, this work performed biochemical and biological profile of macroglands parotoid secretion from cane toad. For poison analysis, we performed molecular exclusion and reverse phase chromatography, electrophoresis, and mass spectrometry. Antimicrobial, antiplasmodial, leishmanicidal, cytotoxicity, genotoxicity, and inflammatory activity of crude and/or fractions of R. marina secretion were also evaluated. Fractionation prior to filtration from poison showed separation of low mass content (steroids and alkaloids) and high molecular mass (protein). Material below 10 kDa two steroids, marinobufagin and desacetylcinobufagin, was detected. Crude extract and fractions were active against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Plasmodium falciparum, Leishmania guyanensis, and Leishmania braziliensis. Crude extract was also active against cancer cells although it was not cytotoxic for normal cells. This extract did not show significant DNA damage but it showed an important inflammatory effect in vivo. The information obtained in this work contributes to the understanding of the constituents of R. marina secretion as well as the bioactive potential of these molecules. [ABSTRACT FROM AUTHOR]

Combretum leprosum Mart., a member of the Combretaceae family, is a traditionally used Brazilian medicinal plant, although no evidence in the literature substantiates its antioxidant action and the safety of its use. We evaluated the antioxidant properties of the ethanolic extract (EE) from flowers of C. leprosum and its isolated products 5,3′-dihydroxy-3,7,4′-trimethoxyflavone (FCL2) and 5,3′,4′-trihydroxy-3,7-dimethoxyflavone (FCL5) in Saccharomyces cerevisiae strains proficient and deficient in antioxidant defenses. Their mutagenic activity was also assayed in S. cerevisiae, whereas cytotoxic and genotoxic properties were evaluated by MTT and Comet Assays, respectively, in V79 cells. We show that the EE, FCL2, and FCL5 have a significant protective effect against H2O2. FCL2 showed a better antioxidant action, which can be related to the activation of the 3′-OH in the presence of a methoxyl group at 4′ position in the B-ring of the molecule, while flavonoids did not induce mutagenesis in yeast, and the EE was mutagenic at high concentrations. The toxicity of these compounds in V79 cells increases from FCL2 = FCL5 < EE; although not cytotoxic, FCL5 induced an increase in DNA damage. The antioxidant effect, along with the lower toxicity and the absence of genotoxicity, suggests that FCL2 could be suitable for pharmacological use. [ABSTRACT FROM AUTHOR]