A comprehensive evaluation of Neolamarckia cadamba leaves: Nutritional, elemental, and polyphenolic profiles with antioxidant properties

Medicinal plants are increasingly valued as natural sources of bioactive compounds with therapeutic potential. Neolamarckia cadamba ( N. cadamba ) leaves are traditionally used in ethnomedicine; however, comprehensive studies integrating their nutritional composition, phytochemical profile, and antioxidant potential are limited. This study aimed to address this gap by systematically evaluating the proximate composition, elemental and anion content, polyphenolic compounds, and in vitro antioxidant activity of N. cadamba leaves. Proximate analysis revealed notable protein content (14.70 ± 0.36%), while elemental analysis showed high levels of calcium (1214.0 ± 2.36 mg/100 g), potassium (610.57 ± 0.45 mg/100 g), and magnesium (257.97 ± 0.56 mg/100 g). Anion analysis indicated significant sulfate (137.46 ± 4.74 mg/100 g) and phosphate (126.71 ± 5.60 mg/100 g) content. Among different solvent extracts, the direct ethanolic extract exhibited the highest total phenols (74.08 ± 6.96 mg GAE/g), tannins (60.40 ± 2.22 mg TAE/g), and flavonoids (28.22 ± 1.59 mg QE/g). LC-MS analysis identified several polyphenols, including catechin, vanillin, rutin, and quercetin, with particularly high levels of catechin (1830.0 ± 0.99 mg/100 g) and vanillin (581.0 ± 1.05 mg/100 g). The direct ethanolic extract also demonstrated the strongest antioxidant activity, with the highest total antioxidant capacity (116.24 ± 7.97 mg AAE/g) and lowest IC₅₀ values for DPPH (5.43 ± 0.44 µg/mL) and ferric reducing activity (35.43 ± 0.59 µg/mL). These findings establish N. cadamba leaves as a promising source of nutrients and natural antioxidants, supporting their potential application in functional foods, nutraceuticals, and pharmacological formulations.