In vitro antimicrobial and cytotoxic evaluation of a PEG/soy lecithin nanosuspension as acetogenin carrier systems

Acetogenins (ACGs) are bioactive compounds with antifungal, antibacterial, and cytotoxic activities; however, their poor water solubility limits their pharmaceutical applications. A polyethylene glycol/soy lecithin/ACGs nanosuspension (PEGSL-ACGs-NSps) was developed to evaluate antifungal (Candida spp.), antibacterial (bacterial pathogens), and cytotoxic activities (tumor or healthy cell lines) using microdilution and MTT assays. MIC and IC₅₀ values were determined to compare the efficacy of PEGSL-ACGs-NSps and free ACGs. PEGSL-ACGs-NSps showed complete growth inhibition of C. glabrata and C. tropicalis within 5 h at 2.5-3.2 mg/mL, whereas free ACGs required 24-48 h. IC₅₀ values indicated higher antifungal potency for NSps (1.64-1.81 mg/mL) compared to free ACGs (1.94-2.27 mg/mL). Against E. coli and B. cenocepacia, both PEGSL-ACGs-NSps and free ACGs achieved complete inhibition at 3.2 mg/mL, with IC₅₀ values ranging from 0.18 to 1.01 mg/mL. In cytotoxicity assays, ACGs free and PEGSL-ACGs-NSps exhibited high activity against tumor cell lines, with IC₅₀ values ranging from 7.01 to 25.30 μg/mL and inhibition values of 81.97-100%. In contrast, NSps IC₅₀ (31.50 μg/mL) was higher in the HaCaT cells than free ACGs (6.05 μg/mL). Overall, PEGSL-ACGs-NSps improved the in vitro biological performance of acetogenins, suggesting their potential as nanosuspension-based delivery systems.