Actividad bactericida in vitro de Chenopodium quinoa Willd. y Artemisia dracunculus L. sobre bacterias patógenas

Introduction: Indiscriminate use of antibiotics for the treatment of bacterial infections has led to the emergence of resistant bacterial strains, which has motivated the search for alternatives for their control, such as the use of plant extracts that have shown potential as bactericides, e.g. Chenopodium quinoa Willd. and Artemisia dracunculus L, which are commercially cultivated in Colombia and neighboring countries. Objectives: To define the antibacterial activity of extracts from C. quinoa (quinoa) seeds and A. dracunculus (Russian tarragon) leaves. Methods: Extraction from C. quinoa seeds and A. dracunculus leaves was carried out by maceration at room temperature. The solvents used were methanol, hexane, and ethyl acetate. The three extracts obtained were tested against Staphylococcus aureus ATCC® 6538™ and Escherichia coli ATCC® 25922™ by well diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) methods. Results: The methanolic extract of A. dracunculus at a concentration of 0.02 g/ml, generated average inhibition haloes of 30.67 mm for E. coli and 32 mm for S. aureus . At the same concentration, the methanolic extract of C. quinoa generated average inhibition haloes of 28.33 mm for S. aureus and 30 mm for E. coli . The strains of both bacteria showed high sensitivity (0.01 g / ml) to the A. dracunculus extract. For the C. quinoa extract, the strains of S. aureus (0.05 g / ml) and E. coli (0.1 g / ml) showed low sensitivity. Conclusions: The MIC and MBC of the methanolic extracts of both plants were the same, which classifies their activity as bactericidal against the strains of the microorganisms evaluated. The extract of A. dracunculus shows greater potential since the microorganisms displayed high sensitivity to it. Key words: antibacterial; microbial sensitivity tests; plant extracts; Chenopodium quinoa Willd; Artemisia dracunculus L.