Characterization of bioactivity and development of chitosan-based nanostructured systems containing Momordica charantia L. extracts

Abstract

Momordica charantia L. contains bioactive compounds associated with antioxidant, enzymatic, and cytotoxic activities, attracting interest in the development of nanostructured systems for the delivery of plant extracts. This study aimed to evaluate the biological potential of hydroethanolic extracts from the leaves and fruits of M. charantia and to develop chitosan and sodium tripolyphosphate (CS/TPP)-based nanostructured systems, investigating their physicochemical characteristics and in vitro cytotoxic activity. Initially, the extracts were evaluated for their phenolic and flavonoid contents, antioxidant activity, total antioxidant capacity, α-amylase activity, and preliminary toxicity using Artemia salina. Subsequently, the extracts were incorporated into CS/TPP systems, which were characterized in terms of particle size, encapsulation efficiency, and Raman spectroscopic profile. The cytotoxicity of the formulations was evaluated using the MTT assay in HeLa and RAW 264.7 cells at different concentrations, with determination of IC₅₀ values. The extracts exhibited antioxidant and enzymatic activities, as well as concentration-dependent preliminary toxicity. The nanostructured formulations showed encapsulation efficiencies of 84.53% for the fruit extract and 81.00% for the leaf extract, with particles in the nanometric range and preservation of the main spectroscopic characteristics of the extracts after the encapsulation process. In the cytotoxicity assessment, the formulations exhibited concentration-dependent effects. In HeLa cells, formulations containing fruit and leaf extracts showed IC₅₀ values of 44.90 mg/mL and 54.30 mg/mL, respectively. In RAW 264.7 cells, the IC₅₀ values were 59.06 mg/mL and 23.96 mg/mL, respectively. Chitosan nanocapsules without extract also exhibited cytotoxicity, indicating that the polymeric matrix may contribute to the observed cellular response. The results demonstrated that M. charantia extracts exhibited bioactivity and that their incorporation into CS/TPP systems is feasible, with preservation of extract characteristics and in vitro cytotoxic activity. These findings support the potential of the developed systems for future investigations, particularly regarding cellular selectivity, mechanisms of action, stability, and preclinical evaluation.