Antimicrobial Activity of Essential Oils Obtained from Aromatic Plants of Argentina

Abstract

The aim of this work was to evaluate the antibacterial and antifungal activity of essential oils obtained from medicinal plants of the Argentine Republic. The antimicrobial activity of the essential oils of 14 plants collected from different zones was analyzed. The microorganisms used were Staphylococcus aureus, Staphylococcus epidermidis, Bacillus cereus, Micrococcus luteus, Enterococcus faecalis, Escherichia coli, Klebsiella sp., Proteus mirabilis, Pseudomonas aeruginosa, and the yeast Candida albicans. The disk diffusion method was performed to test antimicrobial activity. B. cereus and S. aureus were inhibited by most of the essential oils. Aloysia triphylla, Psila spartoides, and Anemia tomentosa were the most effective compounds against B. cereus, while A. triphylla and Baccharis flabellata were effective against S. aureus. None of the oils inhibited P. aeruginosa. B. flabellata and Pectis odorata were active only against Gram-positive bacteria. A. triphylla and P. spartoides inhibited all tested microorganism, and the remaining essential oils showed variable activity. The minimum inhibitory concentration (MIC) of A. triphylla and P. spartoides essential oils were determined using the disk diffusion method. The lowest MICs were against S. aureus (1=16), B. cereus (1=16), S. epidermidis (1=8), and C. albicans (1=32) for A. triphylla. The lowest MICs were against S. aureus (1=32), B. cereus (1=32), P. mirabilis (1=32), and C. albicans (1=64) with P. spartoides. The results showed that B. cereus and S. aureus were the most sensitive microorganisms, and P. aeruginosa was the most resistant microorganism. This study may contribute to improve ethnobotanical knowledge and would help to discover substances with potential therapeutical uses, as food preservants or as food-borne pathogen inhibitors.

Cytotoxic Activity of Argentinean Essential Oils onArtemia salina.

“…S. aureus is responsible for human diseases and is a food-contaminating microorganism, as is B. cereus, a spore-forming bacilli. It is also important to note that in previous studies A. triphylla showed a remarkable antifungal activity against Candida albicans (Hammer et al, 1998;Demo et al, 2005). As a consequence, this nontoxic essential oil could be considered as a potential antifungal agent against mucous and cutaneous candidiasis.…”

“…A. polystachia was active against Staphylococcus aureus, Bacillus cereus, and Proteus mirabilis (Primo et al, 2001;Gonzalez et al, 2004;Demo et al, 2005). It is important to note that A. polystachya was nontoxic at the maximum tolerated concentration (MTC; 3530 mg=mL).…”

“…The most toxic essential oils were Psila spartoides (LC 50 14 mg=mL) and Hyptis mutabilis (LC 50 30 mg=mL). It is also important to note that Lantana xenica (LC 50 995 mg=mL), Ophryosporus charrrua (LC 50 972 mg=mL), and Anemia tomentosa (LC 50 968 mg=mL) toxic values were very near the nontoxicity limit value, taking into consideration that the oils of the three vegetables showed antimicrobial activity in previous studies Demo et al, 2005).…”

“…It is important to note that A. polystachya was nontoxic at the maximum tolerated concentration (MTC; 3530 mg=mL). The essential oils of A. triphylla were active against Gram-positive bacteria, such as S. aureus, S. epidermidis, B. cereus, Micrococcus luteus, Enterococcus faecalis, and Gram-negative bacteria, such as Escherichia coli, Klebsiella pneumoniae, and P. mirabilis (Demo et al, 2005). S. aureus is responsible for human diseases and is a food-contaminating microorganism, as is B. cereus, a spore-forming bacilli.…”

Evaluación <i>in vitro</i> de la capacidad antimicrobiana del aceite esencial de eneldo -<i>Anethum graveolens</i>- como inhibidor del crecimiento de <i>Staphylococcus aureus</i>, coliformes y hongos presentes en la carne de trucha

“…Se sugiere que la actividad individual de estos componentes está directamente relacionada con el efecto inhibitorio que presenta este estudio. En egfecto, la actividad antibacteriana del aceite esencial posiblemente se deriva de sus componentes principales, como el carvacrol, componente que permeabiliza la membrana celular, además de ser capaz de desintegrar la membrana externa de las bacterias Gramnegativas (Demo et al 2005). En general, los aceites esenciales son un poco más activos frente a las bacterias Grampositivas que ante las bacterias Gramnegativas (Gandhi y Chikindas 2007); sin embargo, no todas las investigaciones sobre los aceites esenciales han llegado a la conclusión de que los microorganismos Gram-positivos son más susceptibles.…”