Evaluación de la actividad antimicrobiana In Vitro de diferentes extractos del Líquen Parmelina Tiliacea

Abstract

This research aimed to evaluate the in vitro Antimicrobial activity of different Parmelina tiliacea lichen extracts and determine the presence of lectins performing a Lichen haemagglutinating activity. During the period June-August 2015, it was worked with four lichen extracts: alcohol, acetone, ethyl acetate and water, all obtained by reflux, heat and evaporated to dryness. The antimicrobial activity was performed using methods such as: micro-drop and disc diffusion using dissolved extracts in Dimethyl Sulfoxide (DMSO) and dilutions of these, against microorganisms American Type Culture Collection (ATCC) of: Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumoniae and Candida albicans, this activity was compared with antimicrobial standards like: ceftriaxone (30 µg), erythromycin (15µg), ketoconazole (25µg), and negative controls like: DMSO, sterile water. For haemagglutinating activity, it was used the aqueous extract and their dilutions using a suspension of erythrocytes in 5% of blood groups (O⁺, A⁺, B⁺, AB⁺). The antimicrobial effect was measured by aura inhibitors, while the presence of lectins was assessed according to the intensity of agglutination that erythrocytes suffered. It is concluded that all extracts have in vitro antimicrobial action for the least one ATCC strain, except for the Escherichia coli bacterium, which was not inhibited by any extract. The type of microorganism and the nature of the extract are factors which established antimicrobial potential and the ethyl acetate extract of Parmelia tiliacea lichen showed the highest activity against Staphylococcus aureus, also it was determined that there are lectins being part of Lichen composition, despite the lack of its presence in high concentrations. It is recommended to study their effect as a treatment for cancer as well as to perform a thoroughly research of their amino acid composition.