ABSTRACT

The need to explore natural supply of novel antimicrobial agent has increased in the past three decades. An observed shift from synthetic antimicrobial agent to natural products of plant origin may be due in part to the growing resistance of microorganism to the few existing synthetic antimicrobial agents.  Avocado seeds are cultivated and used as food in most tropical and subtropical countries. Its high nutritional value and biological activities, as antioxidant, antimicrobial and analgesic properties have been thoroughly investigated.

This study evaluated the antimicrobial activity, phytochemical analysis, and time kill assay of the ethylacetate extract of Persea americana seed. Antimicrobial activity of the seed extract was evaluated against clinical isolates (Escherichia coli, Staphylococcus aureus, Klebsiella aerogenes, Pseudomonas aeruginosa, Pseudomonas florescens, Enterobacter spp, Proteus vulgaris and Candida albicans) using agar-well diffusion and agar dilution methods.

 Phytochemical analysis was carried out with standard methods. Result obtained showed an oily dark-brown coloured extract with a yield of 4.026 %. The extract showed activity against most test microorganisms with inhibition zone diameter range of 12mm to 20.50mm. Phytochemical studies revealed the presence of alkaloids, saponins, phenols, cardiac glycosides, reducing sugar as well as carbohydrate. The time kill kinetics revealed the bacteriostatic and bactericidal activity against various test organisms. This study has shown that ethyl acetate extract of Persea americana seed possessed antimicrobial activity. Thus, our study has established a scientific basis for the traditional use of Persea americana seed recipein the treatment of infections.