Phytochemical analysis and antimicrobial activity of the fruit and petiole extracts of Alocasia longiloba against Escherichia coli and Staphylococcus aureus

Abstract

Medicinal plants and their secondary metabolites have been reported to have antimicrobial activities against several microorganism. Despite A. longiloba ethnomedicinal benefits, its antimicrobial activity is not yet reported. Hence, this study aimed to investigate the phytochemical and antimicrobial activity of ethanolic fruit and petiole extracts of A. longiloba against E. coli and S. aureus. Our results show, the ethanolic fruit and petiole extracts of A. longiloba possess various group of important phytochemical compounds among them are phenolic, flavonoids, alkaloids, glycoside, saponins, terpenoids and tannins. For in vito antimicrobial tests, both extracts of A. longiloba exhibited promising antimicrobial activity against E. coli and S. aureus. All three different concentrations (5, 25 and 50 mg/mL) of fruit extract exhibited more than 90% and 80% in S. aureus and E. coli reduction in cfu/mL respectively. Whilst, the petiole extract shows more than 80% reduction effect in cfu/mL in both bacteria. In conclusion, the fruit extract exhibited the best antimicrobial activity against both bacteria with a significant reduction in cfu/mL and the antibacterial activity might attribute to the phytochemicals present in the crude extracts. These results indicate A. longiloba is a potential bactericidal agent.