Harnessing Desert Flora: Biogenic Silver Nanoparticles from Desert Plants Combat Bacterial Infections and Biofilm Formation

In this study, we harnessed the properties of desert plants to synthesize silver nanoparticles to explore potential antimicrobial solutions. Chrozophora plicata and Heliotropium curassavicum extracts were used as green reducing agents to transform silver ions into nanoparticles. Our findings revealed novel properties of C. plicata, which have not been reported before. Surface plasmon resonance peak at 453.6 and 431 nm for C. plicata and H. curassavicum, respectively, via ultraviolet (UV) spectral analysis evidenced the successful fabrication of silver nanoparticles with particle sizes ranging from 4.3–8 and 3.1–6.97 nm respectively, which was validated by field emission scanning electron microscopy (FE-SEM). X-ray diffraction analysis revealed that the crystal structure of these nanoparticles had a face-centered cubic geometry. Fourier transform infrared spectrometry of the plant extract showed strong signals corresponding to carbohydrates, proteins, and phenolics. Antibacterial assays of the silver nanoparticles from C. plicata displayed zones of inhibition at 5 and 4 mm against Staphylococcus aureus and Escherichia coli, respectively. Meanwhile, the silver nanoparticles from H. curassavicum exhibited zones of inhibition against both pathogens at 10 and 7 mm, respectively. The test samples were substantial inhibitors of S. aureus and E. coli biofilm formation since these displayed IC₅₀ values in the range of 8.88–10.57 mg/mL, which is as potent as the reference ciprofloxacin. Consequently, the silver nanoparticles derived from these desert plants can be potential drug candidates for treating respiratory and digestive tract infections alone or in combination with existing antibiotics.