relation: http://eprints.science-line.com/id/eprint/1532/ title: Antimicrobial Activity of Ziziphus spina-christi against Staphylococcus aureus, Escherichia coli and Shigella flexneri creator: Mohammed Musa, Hamasat creator: Okoth Odari, Eddy creator: Benjamin Ochieng, John subject: SF Animal culture description: Antibiotic resistance remains a global concern, with up to 1.91 million deaths projected to occur due to resistant Gram-negative and Gram-positive bacteria by 2050. The study hence aimed to assess the antimicrobial activity of Ziziphus spina-christi leaf extracts in relation to specific bacterial strains and elucidate the molecular mechanisms to validate the in vitro findings. Ziziphus spina-christi leaf extracts were tested against Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Shigella flexneri (S. flexneri). The leaf powder was subjected to both aqueous and methanol-dichloromethane extraction. Phytochemical products were determined by Liquid Chromatography-Mass Spectrometry and Gas Chromatography-Mass Spectrometry for water extract and methanol dichloromethane extract, respectively. The agar well diffusion method, broth microdilution, and minimum bactericidal concentration against three bacterial species, S. aureus, E. coli, and S. flexneri, were used to assess the antibacterial activity of extracts. The results have shown that both plant extract has a significant level of antibacterial activity at higher concentrations (400 mg/ml) against the gram-positive bacteria. In addition, the methanol-dichloromethane extract exhibited the highest antibacterial activity against Gram-negative bacteria (S. flexneri, and E. coli), conversely, the water extract demonstrated a lower activity against S. flexneri and E. coli, with inhibition zones of 15 ± 0 mm for both bacteria. At a lower concentration (100 mg/ml), the methanol-dichloromethane extract produced inhibition zones of 19.6 ± 0.5 mm against S. aureus, closely followed by S. flexneri and E. coli. The water extract exhibited high antibacterial activity against Gram-positive bacteria. However, exhibited reduced antibacterial activity against S. flexneri and E. coli, indicating a concentration-dependent antibacterial effect. Extraction methods were significantly different, with products generated from non-aqueous extraction demonstrating a higher potency against both Gram-negative and Gram-positive bacteria than the aqueous extract. Docking results demonstrated that water extract had a high binding activity against penicillin-binding proteins. Moreover, it serves as a potent beta-lactamase inhibitor as it binds to their active site, rendering them inactive and inhibiting the hydrolysis of Beta lactam antibiotics. In conclusion, the methanol-dichloromethane and water Ziziphus spina-christi leaves could be considered a promising source of antimicrobial ingredients. publisher: Scienceline Publication date: 2025-03-30 type: Article type: PeerReviewed format: text language: en identifier: http://eprints.science-line.com/id/eprint/1532/1/WVJ15%281%29%20143-161%2C%202025%20%281%29.pdf identifier: (2025) Antimicrobial Activity of Ziziphus spina-christi against Staphylococcus aureus, Escherichia coli and Shigella flexneri. World’s Veterinary Journal. pp. 141-161. ISSN 2322-4568 relation: https://wvj.science-line.com/attachments/article/85/WVJ15(1)%20143-161,%202025.pdf relation: 10.54203/scil.2025.wvj17