Microencapsulation-mediated modulation of phytochemical stability and antioxidant performance in Annona muricata L. leaf extracts under controlled drying and extraction conditions

Abstract

Annona muricata L. (soursop) is a pharmacologically important tropical plant known for its rich profile of bioactive compounds and therapeutic potential. The leaves of A. muricata have gained significant attention for their medicinal value in functional foods, plant-based formulations, and phytopharmaceutical applications, mainly because of their high concentration of secondary metabolites, particularly acetogenins. The present study aimed to optimize the extraction and microencapsulation of A. muricata leaf extract to improve the stability of its bioactive constituents. Among the drying methods evaluated, shade drying was the most effective. It preserved an optimal moisture content of 67.92 plus-minus 0.065 percent while maintaining phytochemical integrity and minimizing thermal degradation. Extraction using 100 percent methanol (T2) gave the highest total extract yield, total phenolic content (1.10 plus-minus 0.007nmg GAE/g), and acetogenin concentration. This extract also showed the best antioxidant activity, with the lowest IC sub(50) value of 116 Mu g/mL in the DPPH radical scavenging assay. Microencapsulation using sodium alginate, inulin, and gum arabic produced stable emulsions with particle sizes ranging from 250 plus-minus 0.005 nm to 6943.47 plus-minus 0.003 nm. The highest emulsion stability index (99.33 plus-minus 0.1 percent at 24 h) was recorded for formulations combining gum arabic and sodium alginate with distilled water extract. Overall, microencapsulation is an effective strategy to control release kinetics, improve therapeutic efficacy, and reduce risks associated with rapid degradation or uncontrolled release of bioactive compounds. These findings indicate that the selected drying, solvent extraction, and microencapsulation approaches support the potential of A. muricata leaves as a resource for scalable nutraceutical and functional food applications.