Adansonia Digitata Leaf Extract Nanoemulsions for Chlorophyll-Based Photodynamic Therapy: A Novel Green Approach for Combating Cancer and Microbial Infection

Abstract

Abstract Purpose Photodynamic therapy (PDT) is an approach for cancer treatment and microbial infections that depends on the light excitation of a photosensitizer with a high yield of reactive oxygen species. Consistent with sustainable development goals, Adansonia digitata leaf extract (ADLE) loaded in nanoemulsions from natural components (ADLE-NE) was investigated as a promising natural photosensitizer. Methods The generation of singlet oxygen by ADLE was monitored via a 1,3-diphenylisobenzofuran assay. The in vitro cytotoxicity of ADLE and ADLE-NE was evaluated in normal HEK293 cells and cancerous A549 cells. The antimicrobial PDT of ADLE-NE was tested on methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa . Confocal Laser Scanning microscope (CLSM) and double fluorescent staining were performed to visualize bacterial uptake and the effect of aPDT. Results The absorption of 1,3-diphenylisobenzofuran decreased by 97.8% after 40 s of irradiation. The prepared ADLE-NE had a particle size of 289.37 ± 16.46 nm, a PDI of 0.37 ± 0.02 and a zeta potential of − 35.28 ± 2.51 mV. ADLE-NE exhibited significant phototoxicity to cancer cells, with significant early apoptosis. The PDT of 10 µg/ml ADLE or ADLE-NE on cancer cells showed 68.31 ± 14.53% and 48.71 ± 7.53% viability, respectively. The antimicrobial PDT of 10 µg/ml ADLE-NE on MRSA and Pseudomonas aeruginosa showed viabilities of 1.41 ± 0.84% and 32.61 ± 7.53%, respectively. CLSM revealed significant uptake from ADLE-NE with visible live/dead cells following aPDT. Conclusion These results suggest that ADLE is a promising photosensitizer for the photodynamic therapy of cancer and microbial infections, especially after loading in nanoemulsions.