ABSTRACT
The emergence of fungal resistance to commercial drugs has been a major problem for the WHO. In this context, research with natural products is promising in the discovery of new active substances. Thus, this work evaluated the antifungal effect of a medicinal plant (i.e., Mesosphaerum suaveolens) against strains of the genus Candida, tested the combined effect with the drug fluconazole, and, finally, determined the phenolic constituents present in the species. Initially, aqueous extracts of leaves (AELMs) and aerial parts (AEAPMs) of the species were prepared. For microbiological assays, the minimum fungicidal concentration was determined by broth microdilution, and the combined effect of fluconazole extracts were verified by sub-inhibitory microdilution concentrations (CFM/8) followed by spectrophotometric readings which were used to determine the IC50. HPLC detected the presence of flavonoids and phenolic acids, detecting eight compounds present in the samples of which caffeic acid and quercetin were major components. The AELMs modulated fluconazole activity since it decreased fluconazole's IC50 from 7.8 µg/mL to an IC50 of 4.7 µg/mL (CA LM 77) and from 28.8 µg/mL to 18.26 µg/mL (CA INCQS 40006) for the C. albicans strains. The AEAPMs were able to potentiate the effect of fluconazole more effectively than the AELMs. Such an effect was significant for the 16 µg/mL concentration for CA LM 77 and 32 µg/mL for CA INCQS 40006. The AEAPMs as well as the AELMs presented clinically relevant activities for C. tropicalis strains. For the C. tropicalis LM 23 strain, the AEPMs obtained an IC50 of 25 µg/mL and the AELMs an IC50 of 359.9 µg/mL.
ABSTRACT
This experiment was carried out to tudy the bioacaricidal efficacy of ethanolic extract from the leaves of Hyptis suaveolens (L) Poit (Lamiaceae) against engorged females of Rhipicephalus (Boophilus) microplus. 100 engorged females of R. (B.) microplus were manually collected from a naturally infested herd. The females were subjected to the immersion test at three concentrations of the ethanolic extract: 0,1; 1,0 and 10µg/mL, with two replications in each reatment. It was ound efficacy of 10% in all concentrations. The data found in this study show that the ethanolic extract from the leaves of H. Suaveolens do not have bioacaricidal activity at the used concentrations.
Subject(s)
Hyptis/cytology , Hyptis/chemistry , Lamiaceae/cytology , Lamiaceae/chemistry , Rhipicephalus , PhytotherapyABSTRACT
This experiment was carried out to tudy the bioacaricidal efficacy of ethanolic extract from the leaves of Hyptis suaveolens (L) Poit (Lamiaceae) against engorged females of Rhipicephalus (Boophilus) microplus. 100 engorged females of R. (B.) microplus were manually collected from a naturally infested herd. The females were subjected to the immersion test at three concentrations of the ethanolic extract: 0,1; 1,0 and 10µg/mL, with two replications in each reatment. It was ound efficacy of 10% in all concentrations. The data found in this study show that the ethanolic extract from the leaves of H. Suaveolens do not have bioacaricidal activity at the used concentrations.(AU)