Designing Alginate/Chitosan Nanoparticles Containing<i>Echinacea angustifolia</i>: A Novel Candidate for Combating Multidrug‐Resistant<i>Staphylococcus aureus</i>

Abstract

Nanoparticles (NPs) may help treat multidrug-resistant Staphylococcus aureus (MDR). This study prepared and evaluated chitosan/alginate-encapsulated Echinacea angustifolia extract against MDR strains. Evaluating synthesized NPs with SEM, DLS, and FT-IR. Congo red agar and colorimetric plate techniques examined isolate biofilm formation. NP antibacterial power was assessed using well diffusion. Real-time PCR assessed biofilm-forming genes. MTT assessed the synthesized NPs' toxicity. According to DLS measurements, spherical E. angustifolia NPs had a diameter of 335.3±1.43 nm. The PDI was 0.681, and the entrapment effectiveness (EE%) of the E. angustifolia extract reached 83.45 %. Synthesized NPs were most antimicrobial. S. aureus resistant to several treatments was 80 percent of 100 clinical samples. Biofilm production was linked to MDR in all strains. The ALG/CS-encapsulated extract had a 4 to 32-fold lower MIC than the free extract, which had no bactericidal action. They also significantly decreased the expression of genes involved in biofilm formation. E. angustifolia-encapsulated ALG/CS decreased IcaD, IcaA, and IcaC gene expression in all MDR strains (***p<0.001). Free extract, free NPs, and E. angustifolia-NPs had 57.5 %, 85.5 %, and 90.0 % cell viability at 256 μg/ml. These discoveries could assist generate stable plant extracts by releasing natural-derived substances under controlled conditions.