Evaluation of the Inhibitory Activity of Tannin Extracts from the Leaves and Flowers of Capparis spinosa L. Against Multidrug-Resistant Staphylococcus aureus

The results of the present study revealed the successful isolation and identification of Staphylococcus aureus bacteria from various clinical infections, obtaining 11 isolates out of 25 samples. The isolates exhibited very high resistance to aztreonam (100%), piperacillin (90.9%), and ceftriaxone (90.9%), while demonstrating complete susceptibility (100%) to both imipenem and meropenem. Furthermore, the results of the phenotypic detection of virulence factors showed the ability of some Staph. aureus isolates to produce beta-lactamase enzyme at a rate of 36.4% and hemolysin at 63.63%, in addition to the ability of all isolates to form a dense slime layer associated with biofilm formation. The floral tannin extracts of Capparis spinosa showed superior antibacterial inhibitory activity compared to leaf extracts, with the maximum inhibition zone diameter reaching 23 mm at 100% concentration. This result indicates that C. spinosa flowers may represent a promising natural source of compounds with antibacterial activity against Staph. aureus, particularly antibiotic-resistant isolates.