Comparison of Antimicrobial Activity and Phytochemical Screening of Seeds and Testas of Dacryodes edulis and Garcinia kola

Abstract

The aim of this study was to evaluate the seeds and testas of Dacryodes eludis and Garcinia kola for antimicrobial activity against bacterial and fungal isolates in addition to their screening for phytochemicals and quantification. Phytochemical screening with aqueous and ethanolic extracts, crude quantification of phytochemicals and antimicrobial sensitivity assay were all carried using standard techniques. Resulting replicate readings were subjected to statistical analysis to test for significance. The results of the phytochemical screening indicates the presence alkaloids, glycosides, saponins, tannins, flavonoids, reducing compounds and polyphenols but not phlobatannins, anthraquinones and hydroxymethyl anthraquinones in the aqueous and ethanolic extracts of the seeds and testas of Dacryodes eludis. However, in addition, phlobatannins was found in the testa and seeds of G. kola. Following quantification of the phytochemicals, the most abundant were polyphenol and tannins in the testa and seeds of D. eludis and G. kola, respectively. Analysis of variance showed significance (p < 0.05). The extracts showed varying levels of inhibition against the bacterial and fungal isolates. Consistently, the methanolic extract of G. kola seed gave the highest zones of inhibition against the bacterial isolates while its ethanolic extract also showed consistent antifungal activity. This is an urgent need for further studies aimed at further exploiting these phytochemicals.