Anti-Colon Cancer and Antibiofilm Activities of Green Synthesized ZnO Nanoparticles Using Natural Polysaccharide Almond Gum ( Prunus dulcis )

Two of the main challenges in medicine are the fight against antibiotic resistance and cancer, and nowadays, nanomaterials are being postulated as potential alternatives to traditional treatments. Particularly, metal oxide nanoparticles could be an attractive option to replace conventional drugs, which generally present undesirable side effects. Besides, the green synthesis of the NPs provides several advantages, including less contamination. Hence, the present study described a sustainable and simple synthesis of zinc oxide NPs using almond gum Prunus dulcis (Alg-ZnONPs) as the capping agent. The Alg-ZnONPs showed significantly efficient antibacterial and antibiofilm activities against Staphylococcus aureus and Proteus vulgaris . The MIC values of Alg-ZnONPs were 3.25 µg/ml against S. aureus and 2.12 µg/ml against P. vulgaris, which confirm their significant antibacterial activity. Furthermore, the antibiofilm activity against both bacteria was evaluated, disclosing the inhibition of the biofilm growth at 100 μg/ml. Additionally, in vitro anti-colon cancer activity of the Alg-ZnONPs was assessed on a human colon cancer cell line (HT-29), resulting in a significant reduction of the cell proliferation in 24 h, with an IC 50 of 30.69 µg/ml. The present work validates a straightforward and green synthesis of ZnONPs and unravels their potential for developing new antibiofilm agents and anti-colon cancer therapeutics.