Phytochemical profiling, antioxidant and anti-inflammatory potential of methanolic extracts of Moringa oleifera (L.) Lam. and Moringa stenopetala (Bak.) Cufod. leaves grown in Arba Minch, Ethiopia

Abstract

The genus Moringa contains 14 species, including the widely cultivated Moringa oleifera and Moringa stenopetala. They have outstanding nutritional and medicinal advantages. This study aimed to analyze and compare the anti-inflammatory potential, antioxidant capacity, and phytochemical profile of the two species' methanolic leaf extracts. The ultra-high-performance liquid chromatography-high resolution mass spectrometry method was utilized for phytochemical profiling. Total flavonoid content and phenolic content were determined using the colorimetric procedures of aluminum chloride and Folin–Ciocalteu assays, respectively. In vitro, antioxidant activity was measured using 2,2′-casino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and 2,2-diphenyl-1-picrylhydrazyl assays. Protein denaturation and protease activity inhibition assays were employed to determine the anti-inflammatory effects. M. oleifera and M. stenopetala showed similar chemical profiles, with 29 compounds tentatively identified, including glucosinolates, hydroxycinnamic acids, and flavonoid glycosides. M. stenopetala had significantly higher (p < 0.05) total phenolic content (74.23 ± 2.65 mg GAE per g) than that of M. oleifera (66.33 ± 0.40 mg GAE per g), and M. stenopetala also had a greater total flavonoid content (11.27 ± 0.48 mg CE per g) compared to M. oleifera leaf extract (9.19 ± 0.06 mg CE per g) (p < 0.05). M. stenopetala had better antioxidant activity than M. oleifera. Both species of Moringa suppressed egg albumin denaturation and protease activity. M. stenopetala inhibits protein denaturation and protease activity more effectively than M. oleifera. In conclusion, this study showed that both plant species have antioxidant and anti-inflammatory properties, with M. stenopetela exhibiting greater activity than M. oleifera.