Avaliação fitoquímica, antimicrobiana, antioxidante e citotóxica de extratos das algas Hypnea pseudomusciformis, Padina gymnospora e Jania adhaerens

Abstract

The marine environment is distinguished by the diversity of valuable compounds, obtained mainly from the secondary metabolism of marine algae. These secondary metabolites come mainly from defense mechanisms and adaptations to environmental conditions. Leishmaniasis and diseases caused by bacteria and fungi are a worldwide concern due to the constant documented cases of resistance to antimicrobial agents used in their fight. Therefore, the objective of this work was to carry out a phytochemical investigation and to evaluate the antileishmanial, antibacterial, antifungic, antioxidant and citotoxic activity of the hydroalcoholic and hexanic fractions of the following algae: Hypnea pseudomusciformis, Padina gymnospora and Jania adhaerens. The phytochemical study was carried out through qualitative tests and by high performance liquid chromatography (HPLC). The antibacterial

activity was determined by the agar diffusion method. The colorimetric method of resazurin (7-hydroxy- 3H-phenoxazin-3-one-10-oxide) was adopted for antileishmania activity. For antifungal activity, the broth

microdilution method was adopted. The antioxidant activity was determined by the DPPH (1,1-diphenyl- 2-picrylhydrazyl) method. Methodology using Folin-ciocalteau reagent was used for the quantification of

phenols and the cytotoxicity assay was determined by the colorimetric method MTT [3 (- (4,5-dimethyl- 2-thiazole) -2,5-diphenyl-2- H-tetrazolium bromide)]. Among tested algae, the hydroalcoholic fraction of

the red alga Hypnea pseudomusciformis showed the lowest inhibitory concentration for Candida krusei (MIC: 9.76 μg / mL), but no activity for Candida tropicalis, Aspergillus fumigatus and Trycophyton interdigitale was observed. The hydroalcoholic fraction of Jania adhaerens tested against Candida krusei showed a MIC value: 39.06 μg / mL. For the agar diffusion test no fraction of tested algae showed any activity at the concentration tested (10mg/mL) for Staphylococcus epidermidis and Escherichia coli. In the antileishmanial assay was obtained (IC50: 396.8 μg/mL) for the hexane fraction of Hypnea pseudomusciformis. The antioxidant assay revealed that the hydroalcoholic fraction of Hypnea pseudomusciformis presented the highest antioxidant potential (CE50: 256.31 μg/mL) among the tested algae. The quantification of phenols revealed 18.48 and 12.13 of mg GAE/g, for the hydroalcoholic fraction of Padina gymnospora and for the hexanic fraction of Hypnea pseudomusciformis respectively. The cytotoxicity test revealed that no fraction was cytotoxic against the tested cancer cell lines. In this study it was shown that red algae Hypnea pseudomusciformis and Jania adhaerens demonstrated a good performance in the antifungal assay and moderate antioxidant and antileishmanial activity which may encourage deeper studies of these algae species to search for therapeutic components for Candida krusei and L. amazonensis.