Evaluation of mineral content and antioxidant activity of Detarium senegalense leaves extracts

Abstract

This study aimed to evaluate mineral composition and antioxidant activity of Detarium senegalense leaves extracts. Toxic and edible chemotypes of the plant were used. Two free radical scavenging methods using 2,2-diphenyl-1-picryl hydrazyl (DPPH) and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) were employed to evaluate antioxidant activity. Mineral element contents were determined by X-ray fluorescence spectrometry. Ethanolic macerations of leaves were performed and dry extracts obtained, solubilized in water, were fractionated successively using dichloromethane and ethyl acetate. An antioxidant activity was attributed to extracts concentrations between 0.625 and 500 μg/mL. Mean inhibitory concentrations (IC50) ranged from 16.263±0.481 μg/mL to 260.942±36.293 μg/mL for DPPH and 2.707±0.064 μg/mL to 38.238±0.815 μg/mL with ABTS. Analysis of mineral composition revealed presence of various elements such as calcium, phosphorus, potassium, sulfur, chlorine, iron, manganese, copper, zinc and strontium at concentrations ranging from 0.028±0.001 to 24.351±0.157 mg/g. Results showed that Detarium senegalense edible chemotype leaves presented the most important antioxidant activities (ABTS and DPPH). For macroelements, phosphorus, potassium and sulfur were found to be greater in edible chemotype leaves (1.841 ± 0.107, 20.443 ± 0.193 and 4.495 ± 0.089 mg/g) compared to those of toxic chemotype (1.667 ± 0.115, 14.799 ± 0.177 and 3.522 ± 0.089 mg/g respectively). Several microelements (manganese, copper, zinc and strontium) had slightly higher concentrations in toxic chemotype leaves. Therefore, leaves extracts from toxic and edible chemotypes of Detarium senegalense present interesting antioxidant properties. These leaves also constitute a good source of minerals, whose main elements are potassium, calcium, sulfur and phosphorus. The present work reveals that these leaves could be introduced in food formulations and manufacture of inexpensive phytomedicines, notably for low income populations.