Antimicrobial activity of Marcetia DC species (Melastomataceae) and analysis of its flavonoids by reverse phase-high performance liquid chromatography coupled-diode array detector.
BACKGROUND
Marcetia genera currently comprises 29 species, with approximately 90% inhabiting Bahia (Brazil), and most are endemic to the highlands of the Chapada Diamantina (Bahia). Among the species, only M. taxifolia (A.St.-Hil.) DC. populates Brazil (state of Roraima to Paraná) and also Venezuela, Colombia, and Guyana.


OBJECTIVE
This work evaluated the antimicrobial activity of hexane, ethyl acetate, and methanol extracts of three species of Marcetia (Marcetia canescens Naud., M. macrophylla Wurdack, and M. taxifolia A.StHil) against several microorganism. In addition, the flavonoids were analyzed in extracts by HPLC-DAD.


METHODS
The tests were made using Gram-positive (three strains of Staphylococcus aureus) and Gram-negative (two strains of Escherichia coli, a strain of Pseudomonas aeruginosa and another of Salmonella choleraesius) bacteria resistant and nonresistant to antibiotics and yeasts (two strains of Candida albicans and one of C. parapsilosis) by the disk diffusion method. Solid-phase extraction (SPE) was performed on the above extracts to isolate flavonoids, which were subsequently analyzed by high performance liquid chromatography coupled diode array detector (HPLC-DAD).


RESULTS
Results showed that extracts inhibited the Gram-positive bacteria and yeast. The hexane extracts possessed the lowest activity, while the ethyl acetate and methanolic extracts were more active.


CONCLUSIONS
Marcetia taxifolia was more effective (active against 10 microorganisms studied), and only its methanol extract inhibited Gram-negative bacteria (P. aeruginosa and S. choleraesius). SPE and HPLC-DAD analysis showed that M. canescens and M. macrophylla contain glycosylated flavonoids, while the majority of extracts from M. taxifolia were aglycone flavonoids.
Laboratory of Phytochemistry, Department of Health, State University of Feira de Santana, Feira de Santana, Bahia, Brazil.
Tonny Cley Campos
TC
Leite
Amanda Reges
AR
de Sena
Tânia Regina
TR
Dos Santos Silva
Andrea Karla Almeida
AK
Dos Santos
Ana Paula Trovatti
AP
Uetanabaro
Alexsandro
A
Branco