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The increase in the incidence of fungal infections associated with the limited therapeutic arsenal available and the increasing rate of resistance of pathogenic fungi reinforce the need for research of new antifungal agents. Thus, this study aims to evaluate the antifungal activity of the peptide LyeTx I mnΔK, a shortened analogue of the natural peptide LyeTx I derived from spider venom, against Candida species. LyeTx I mnΔK showed potent activity against Candida spp. with minimum inhibitory concentration (MIC) and minimum fungicide concentration (MFC) between 4 and 32 µM. The peptide also completely inhibited the yeast-to-hypha transition (at 2 µM) and broke mature biofilms (67% reduction at 32 µM) of C. albicans. In addition, LyeTx I mnΔK did not induce resistance in C. albicans during 21 days of exposure. Therefore, the LyeTx I mnΔK is a promising prototype for the development of new antifungal agents. [ABSTRACT FROM AUTHOR]

Dengue virus (DENV) is the most prevalent mosquito-borne viral pathogen and made the disease a major health concern worldwide. However, specific antiviral drugs against this arbovirose or vaccines are not yet available for treatment or prevention. Thus, here we aimed to study the antiviral activity of hydroethanolic extract, fraction ethyl acetate and subfractions of the leaves of Bauhinia holophylla (Fabaceae:Cercideae), a native plant of the Brazilian Cerrado, against DENV-2 by methylthiazolyldiphenyl-tetrazolium bromide (MTT) method in mammalian cells culture. As results, the hydroethanolic extract showed the most potent effect, with an inhibitory concentration (IC50) of 3.2 μg mL−1 and selectivity index (SI) of 27.6, approximately 16-times higher anti-DENV-2 activity than of the ribavirin (IC50 52.8 μg mL−1). Our results showed in this study appointed that B. holophylla has a promising anti-dengue activity, which was associated mainly with the presence of flavonoids. [ABSTRACT FROM AUTHOR]

The chemical composition and the phytotoxicity potential of the essential oil from leaves of Unonopsis guatterioides (A.DC.) R.E.Fr. (Annonaceae) was investigated. Gas chromatography/mass spectrometry analyses revealed 16 constituents representing 99.50% of the total essential oil, composed mainly of sesquiterpenes. α-copaene, bicyclogermacrene and trans-caryophyllene were the major components (15.7% each), followed by α-humullene, allo-aromadendrene and (+)-spathulenol (9.0, 8.4 and 7.3%, respectively). The essential oil inhibited seed germination and growth in both monocotyledon (Allium cepa) and dicotyledon (Lactuca sativa) models, pointing to a promising application of this oil obtained from the leaves of U. guatterioides as a new bioherbicide. [ABSTRACT FROM AUTHOR]

Ethanol extract and fractions obtained from fresh and dry aerial parts ofLippia albawere examined in order to determine their phytochemical composition, antioxidant capacity and antibacterial activities. The ethanol extracts and fractions exhibited an antioxidant effect by the DPPH assay, especially samples of fresh plant. HPLC analysis of the ethyl acetate fractions identified the presence of phenolic acids and flavonoids. The ethanol extract and fractions showed activity against reference and multidrug-resistant strains ofStaphylococcus aureusandEnterococcus faecalis(MIC range 2000–250 μg/mL). The hexane and dichloromethane fractions of fresh plant showed better activity against reference strains ofEscherichia coli(MIC of 250 and 125 μg/mL, respectively), but all extracts and fractions were less active against multidrug-resistant strains of all the Gram-negative species evaluated. The results showed that the extract and fractions ofL albaaerial parts showed antibacterial activity, even against multidrug-resistant Gram-positive bacteria, and antioxidant effect (DPPH assay). [ABSTRACT FROM PUBLISHER]