Soon Wei To, Mohd Helmi Sani, Nik Ahmad Nizam Nik Malek, Hendra Susanto, Agustina Tri Endharti, Happy Kurnia Permatasari, Taining Zhang
The rise of antimicrobial resistance (AMR) necessitates novel natural therapeutics. Combining plant extracts offers a promising strategy to enhance antibacterial efficacy via synergistic, multi-target interactions. Bauhinia kockiana, a medicinal vine traditionally used for various treatments, exhibits promising antimicrobial properties, yet the synergistic potential of its multi-organ extracts remains unexplored. This study evaluated the phytochemical profiles and antibacterial activities of aqueous extracts against Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa. Liquid chromatography-mass spectrometry (LC–MS) and Fourier-transform infrared spectroscopy (FTIR) identified 10 organ-specific bioactive phytocompounds and characterized their functional groups. The flower extracts demonstrated the highest total phenolic and flavonoid contents, correlating with superior antibacterial activity. Disc diffusion assays revealed concentration-dependent effects, with flower extracts outperforming streptomycin against MRSA. Minimum inhibitory concentrations (MICs) ranged from 0.125 – 0.5% w/v, with flower extracts showing bactericidal effects against MRSA and P. aeruginosa. Checkerboard assays and well diffusion assays confirmed synergistic flower-stem interactions across multiple pathogens. This combination significantly inhibited S. aureus biofilm formation (> 50% at sub-MIC, complete at 2MIC) and induced morphological deformation. Time–kill kinetics confirmed concentration-dependent bactericidal effects, and mechanistic studies indicated membrane disruption as a primary mode of action, evidenced by enhanced cytoplasmic and protein leakage. These findings highlight the therapeutic potential of B. kockiana multi-organ extracts for combinatorial strategies to combat AMR sustainably. © The Author(s) 2026.
Department of Biosciences, Faculty of Science, Universiti Teknologi Malaysia, Johor Darul Takzim, Skudai, 81310, Malaysia; Centre for Sustainable Nanomaterials (CSNano), Institute Ibnu Sina for Scientific and Industrial Research, Universiti Teknologi Malaysia, Johor Darul Takzim, Skudai, 81310, Malaysia; Department of Biology, Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, Veteran Street, East Java, Malang, 65145, Indonesia; Biomedical Central Laboratory, Faculty of Medicine, Universitas Brawijaya, Veteran Street, East Java, Malang, 65145, Indonesia
