Silver-cored <i>Ziziphus spina-christi</i> extract-loaded antimicrobial nanosuspension: overcoming multidrug resistance supplementary materials

<b>Aims: </b>To synthesize a silver-cored nanosuspension utilizing <i>Ziziphus spina-christi </i>fresh-leaf extract and evaluate their antimicrobial activity against multidrug-resistant pathogenic microbes. <b>Materials and Methods: </b>The prepared nanosuspension was analyzed by spectro-analytical techniques and tested for antimicrobial activity and resistance to biofilm formation. The leaf extract and nanosuspension were tested separately and together as a mixture. <b>Results: </b>Constituent nanoparticles were average-sized (<b>∼</b>34 nm) and were active against both Gram-positive and Gram-negative microbes and yeast. <i>Candida albicans </i>showed a 24.50 <b>± </b>1.50 mm inhibition zone, followed by <i>Escherichia coli </i>and <i>Staphylococcus aureus</i>. Increased bioactivity with the highest multifold increments, 150%, for erythromycin against all tested microbes was observed. Carbenicillin and trimethoprim showed 166%- and 300%-fold increments for antimicrobial activity against <i>Pseudomonas aeruginosa</i>, respectively. <b>Conclusion: </b>The nanosuspension exhibited strong potential as an antimicrobial agent and overcame multidrug resistance.<b>Plain language summary: </b><i>Ziziphus spina-christi </i>leaf extract-coated silver nanoparticles were synthesized using an environment-friendly method, and the preparation was effective against <i>Escherichia coli</i>, <i>Staphylococcus aureus </i>and <i>Candida albicans</i>. The prepared formulation showed increased antimicrobial activity at a 150–300% increase compared with leaf extract-only activity. The prepared suspension was also active against <i>Pseudomonas aeruginosa</i>, the multidrug-resistant microbe, and has the potential to treat drug-resistant microbial infections.