Antioxidant Characterization and Kinetic and Thermodynamic Analysis of Hexane Extracts from Coccoloba uvifera Leaf, Byrsonima crassifolia Bark, and Bursera copallifera Resin

Abstract

The research focused on the thermal decomposition characteristics and the kinetic and thermodynamic parameters of hexane extracts from Coccoloba uvifera leaf (CU), Byrsonima crassifolia bark (BYR), and Bursera copallifera resin (BUR). Additionally, it explored the relationship between these thermal properties and radical-scavenging activity (RSA). The preexponential factor (A), activation energy (Ea), enthalpy (ΔH), entropy (ΔS), and Gibbs free energy (ΔG) were obtained via the Coats–Redfern method. The CU extract showed higher RSA than the BYR and BUR extracts. In thermal analysis, the BYR and BUR extracts had two mass-loss events, whereas the CU extract had three. BUR had the lowest Ea, A, ΔH, and ΔS values, coinciding with its low RSA. Meanwhile, in CU, these parameters had the highest values. The thermal decomposition of the extracts was an endothermic process. Variations in the thermal profile were associated with composition and RSA.