Análisis de la composición química y determinación de la actividad antimicrobiana del extracto Fúngico de una especie del género Cordyceps

Abstract

The main objective of this research study was to analyze the chemical composition and determine the antimicrobial activity of the fungal extract of the genus Cordyceps species. For this reason, the fungal species of the genus Cordyceps were cultivated from the OMAERE Ethno-Botanical Park in the city of Puyo, Pastaza province. The main components were the mycelia obtained by cultivation in the Laboratory of Molecular Biology and Genetics of the Escuela Superior Politécnica de Chimborazo. A Cordyceps extract was elaborated with the maceration technique of dried and pulverized mycelia in an alcoholic medium compound. The extract was evaluated by the method of diffusion in discs at different concentrations: 2000, 1000, and 500 μg/mL respectively. Antibiograms were performed on Mueller Hinton Agar on two bacteria Escherichia coli and Staphylococcus aureus with 0.5 McFarland standard, incubated at 35°C for 18 to 24 hours for the observation of biological activity. This antimicrobial activity was compared with positive control of Chloramphenicol (30 mcg) broadspectrum antibiotic for Gram-positive and Gram-negative bacteria. The highest antimicrobial effect concentrations in the alcoholic extract generated a higher inhibition for Escherichia coli with an inhibition diameter of 9 mm (2500 μg/mL). Positive results of antimicrobial activity were present for both bacterial strains, however, these inhibition halos do not represent the average of commercial antibiotics. The analysis of the chemical composition of the alcoholic extract was determined by phytochemical screening, the biological groups found were: alkaloids, triterpenes, lipids, proteins, and cardiotonic glycosides. It is concluded that there is the presence of functional groups of interest and possible antimicrobial biological activity in the extracts of the fungal species of the genus Cordyceps. It is recommended to identify, quantify, and separate the secondary metabolites present by applying new or complementary techniques.