Comparative Study of Antimicrobial Efficacy and Phytochemical Profiles of Ethanol and n-Hexane Extracts from the Roots of Ixora coccinea Linn

The root extracts of Ixora coccinea were evaluated for their phytochemical composition, antibacterial activity, and minimum inhibitory concentration (MIC) against Escherichia coli, Staphylococcus aureus, and Bacillus subtilis. Quantitative phytochemical analysis was conducted to determine the levels of terpenoids, flavonoids, alkaloids, tannins, and saponins. Thin Layer Chromatography (TLC) was used to confirm the presence of bioactive components in the extracts under different solvent systems, followed by antibacterial susceptibility tests using the disc diffusion method. The MIC was determined through serial dilution to identify the lowest concentration that inhibited bacterial growth. Quantitative phytochemical analysis showed that the ethanol extract contained 14.80% flavonoids, 6.00% alkaloids, 1.20% saponins, 1.80% terpenoids, and 0.03% tannins. In contrast, the n-hexane extract had higher terpenoid content (3.40%) but lower flavonoids (5.20%) and alkaloids (2.10%). Thin Layer Chromatography (TLC) analysis under varying solvent systems showed different Rf values, with the ethanol extract displaying more diverse spots, indicating a richer variety of bioactive compounds. Antibacterial susceptibility tests revealed that the ethanol extract produced larger inhibition zones (10 ± 0.4–28 ± 1.0 mm) than the n-hexane extract (6 ± 0.2–26 ± 0.8 mm). MIC results indicated that ethanol extract inhibited E. coli and S. aureus at 50 mg/L and B. subtilis at 25 mg/L, while the n-hexane extract required 100 mg/L for effective inhibition. In conclusion, the findings indicate that the plant possesses significant antibacterial potential, warranting further research to isolate and characterize the specific phytoconstituents responsible for the observed antimicrobial activities.