HomeOptimavol. 1 no. 1 (2013)


Rvin John T. Servillon | Mary Claire C. Dingal | Marvielyn C. Lusica | Maria Kristina A. Yamson | Mark John B. Balonebro | Florence B. Alzate



The emergence of and increasing mortality from drug resistant bacteria is alarming. The study evaluated the antibacterial property of ripe evergreen avocado (Persea. Americana) peel crude extract. The extract was preliminarily screened for its phytochemical components and revealed the presence of Cardenolides, Bufadienolides, 2-deoxy sugars, unsaturated steroid/triterpenoid, unsaturated lactone, and flavonoids. These phytochemicals are known bioactive components as antimicrobials. Antimicrobial activity of the extract against the reference strains of Staphylococcus aureus (ATCC 25923), Pseudomonas aeruginosa (ATCC 27653), Methicillin-Resistant Staphylococcus aureus (MRSA, ATCC 43300) and other five clinical isolates was carried out using the disc diffusion technique. The results showed that the ripe avocado peel extract possesses antimicrobial activity against all test organisms. The Minimum Inhibitory Concentration (MIC) revealed that S. aureus and MRSA showed the least MIC of 4.375μg/mL, while the reference strains of P. aeruginosa had the highest MIC of 8.75μg/mL. The spectra of antimicrobial activities displayed by the extracts could be attributed to the presence of the identified phytochemicals and signifies the potential of P. amerciana as an antimicrobial agent source. Comparative assays and linear regression computations were done to determine the equipotential concentration of the crude peel extracts’ activity against S. aureus and MRSA using vancomycin as positive control. Results showed that vancomycin concentrations of 196.05μg/ml and 225μg/ml equipotentially inhibited S. aureus and MRSA, respectively, whereas the avocado peel crude extract showed equipotential microbial growth inhibition at 1,120μg/ml (w/v) concentration. The Avocado evergreen variety crude peel extract proved to be an effective antibacterial agent comparable to the commercial antibiotic used as positive control.