Antibacterial, antioxidant, cytotoxicity, and phytochemical screening of Moringa oleifera leaves

Abstract

Bacterial resistance to antibiotics remains a significant clinical challenge, contributing to persistently high rates of morbidity and mortality. Achieving treatment success is increasingly difficult, necessitating the evaluation of new antibiotics and complementary approaches, including source control and alternative therapies. This study aimed to investigate the antibacterial, antioxidant, cytotoxic, and phytochemical properties of Moringa oleifera leaf extract using high-performance liquid chromatography (HPLC), and to evaluate the pharmacokinetic properties of its major compound. The extract demonstrated strong antibacterial activity against standard strains and foodborne bacterial species. It also showed significant antioxidant potential, supported by the presence of high concentrations of phenolic and flavonoid compounds. HPLC analysis identified multiple bioactive compounds, with quercetin as the predominant component. The cytotoxicity study confirmed the safety of the extract at low and moderate concentrations, and ADMET analysis indicated favorable pharmacokinetic characteristics of quercetin. In conclusion, Moringa oleifera exhibits promising potential for medical and food industry applications due to its significant antibacterial and antioxidant activities, combined with a strong safety profile and rich phytochemical content.

Keywords: Moringa oleifera; ADMET analysis; Antibacterial; Antioxidant; Cytotoxicity; Phytochemical compositions; Quercetin.

Fig. 1

Antibacterial activity of methanolic Moringa oleifera leaves extract. C= chloramphenicol, E = erythromycin, G = gentamicin, N = neomycin, A = amoxicillin/clavulanic acid, M = Moringa oleifera extract.

Fig. 2

Transmission electron microscopy (TEM) pictures, (A) untreated K. pneumonia and (A-1) treated, (B) untreated E. coli and (B-1) treated, (C) untreated S. aureus (C-1) treated with Moringa oleifera extract (magnification power = 40000× in case of K. pneumonia and E. coli and 60000× in case of S. aureus).

Fig. 3

Assessment of antioxidant activity in Moringa oleifera extract and ascorbic acid using (A) 2,2-diphenyl-1-picrylhydrazyl (DPPH) and (B) 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS) methods.

Fig. 4

Cytotoxicity of Moringa oleifera leaf extract against HBF4 cell, (A) morphological observation of HBF4 treated with different concentrations of Moringa oleifera leaf extract under an inverted microscope. (B) cytotoxicity results of gradient concentrations of Moringa oleifera leaves extract on HBF4 cells using MTT assay.

Fig. 5

HPLC chromatogram of the methanolic extract of Moringa oleifera leaves extract.

Fig. 6

Radar graphic for the physiochemical characteristics of quercetin predicated by ADMET.