Caracterização físico-química de Aloe vera e atividade antimicrobiana do extrato etanólico liofilizado

Abstract

The use of antibiotics has gradually increased over the years, causing society to seek alternative methods of antimicrobials such as medicinal plants, especially efficient methods that ensure improvement in health. The present work aimed to analyze the physical-chemical characteristics and verify the existence of antimicrobial activity of the lyophilized ethanol extract of Aloe vera. In the physical-chemical evaluation of the plant, pH, total ash, water by desiccation (humidity) and solubility were determined. The physical-chemical characteristics obtained for the study plant were pH of 4.35±0.7; 1.42%±0.15 total ash; 91.62%±1.72 humidity; and solubility in distilled water and ethyl alcohol. The methodology used to verify the antimicrobial capacity of the plant extract was by diffusion in agar and microdilution in broth to determine the minimum inhibition concentration (MIC) of the lyophilized extract of Aloe vera. For the antimicrobial capacity of the extract, the results obtained for diffusion in agar showed that the sensitive microorganisms were Kocuria rhizophila, Staphylococcus aureus and Staphylococcus epidermidis at the concentration of 20 mg.mL-1 and 50 mg.mL-1. In plate microdilution, most microorganisms were sensitive to the extract presenting MIC ≤ 12.5 mg.mL-1 (Bacillus cereus, Bacillus subtilis, Escherichia coli, Kocuria rhizophila, Salmonella typhi, Staphylococcus aureus and Staphylococcus epidermidis). Thus, it was possible to conclude that the results obtained were satisfactory when compared to other related studies and future studies should be directed towards isolating antimicrobial compounds from Aloe vera extract.