The Antioxidant and Antibacterial Activity of Moringa oleifera Extracts against some Foodborne Pathogens

Abstract

The aim of this study is to determine the antioxidant and antibacterial activity of Moringa oleifera extracts.
Maceration and Soxhlet apparatus were used to prepare aqueous and methanolic extracts respectively,
while petroleum ether was used to extract seed oil. Many tests were conducted include, phytochemical
detection, evaluation of antioxidant activity utilizing 2,2- diphenyl-1-picrylhydrazyl (DPPH) assay, total
phenolic content. The extracts of Moringa oleifera were investigated against some foodborne pathogens
include Staphylococcus aureus, Bacillus cereus, Escherichia coli and Klebsiella pneumonia. The results of
phytochemical test showed the presence of alkaloids, phenols, flavonoids, tannins, saponins and glycosides
in aqueous and methanolic leaves extracts. The antioxidant activity showed that the aqueous and methanolic
leaves extract was more effective than the seed’s husk extract. The radical scavenging capacity (EC50) of
methanolic and aqueous leaves extract were found to be (1.6 and 1.9 mg/ml) respectively, while the EC50
of methanolic and aqueous seed’s husk were (5.1 and 10 mg/ml) respectively. The antibacterial activity of
Moringa oleifera extracts showed the best effect was seen in the aqueous and methanolic leaves extract
on Staph. aureus in 200 mg/ml with inhibition zone 14.83 and 22.6 mm respectively. The results of the
minimum inhibitory concentration (MIC) showed that the methanolic leaves extract was 16 mg/ml for both
Staph. aureus and E. coli, and 32 mg/ml for B. cereus and K. pneumonia, while the MIC of aqueous leaves
extract was 64 mg/ml for all bacterial isolates.