Isolation, Characterization, and Antimicrobial Activities of Compounds Isolated from the Plant Ipomoea pes-caprae

Introduction: Ipomoea pes-caprae is a halophyte long used in traditional medicine for skin infections, inflammation, and other ailments. However, no previous study has combined bioassay- guided isolation, in vitro antimicrobial screening, and in silico docking of its secondary metabolites. This work fills that gap by identifying and characterizing the key antimicrobial compounds of I. pes-caprae. Methods: Methanolic whole-plant extracts were fractionated sequentially with chloroform, ethyl acetate, acetone, and n-butanol. Phytoconstituents were profiled by GC-MS, and bioactive leads were isolated via column chromatography and characterized by NMR. Antimicrobial efficacy was evaluated by disc diffusion and broth microdilution assays (determining MIC, MBC, MFC) against Escherichia coli (ATCC 8739), Staphylococcus aureus (ATCC 29737), Salmonella typhi (NCTC 786), Pseudomonas aeruginosa (ATCC 9027), Bacillus subtilis (ATCC 6633), Candida albicans (ATCC 10231), and Aspergillus niger (ATCC 16404). Molecular docking using Auto- Dock Vina assessed interactions of D-Limonene and Camphane with bacterial target 1EI1 and fungal targets 5FSA/1UKC. Results: GC-MS detected 68 compounds; D-Limonene and Camphane were the most potent isolates. D-Limonene showed MICs of 2 µg/mL (all bacteria) and 0.5 µg/mL (both fungi), with corresponding MBCs of 64 µg/mL and MFCs of 32 µg/mL. Camphane had MICs of 8 µg/mL (bacteria) and 2 µg/mL (fungi), with MBCs/MFCs of 64 µg/mL. Docking scores for D-Limonene (– 8.5 kcal/mol vs. 1EI1; –9.6 kcal/mol vs. 5FSA) and Camphane (–7.9; –9.6 kcal/mol) aligned with their in vitro potency. Discussion: D-Limonene and Camphane exhibit broad-spectrum antimicrobial activity, corroborated by strong hydrophobic and π-alkyl interactions in docking. Their efficacy compares favorably to standard drugs (ciprofloxacin, ketoconazole), validating I. pes-caprae as a source of lead scaffolds. Other isolates showed moderate activity, suggesting potential synergistic effects. Conclusion: This study delivers the first integrated isolation–screening–docking investigation of I. pes-caprae, identifying D-Limonene and Camphane as promising antimicrobial leads. Future work should focus on in vivo validation, toxicity profiling, and structural optimization toward novel drug candidates. conclusion: The study demonstrates the antimicrobial potential of D-Limonene and Camphane from I. pes-caprae. These compounds represent promising candidates for the development of new antimicrobial agents, warranting further investigation.