Phytochemical screening by HR-LCMS and In-vitro Antidiarrhoeal activity of Gardenia arborea Roxb.

Objectives: This study aimed to investigate the phytochemical constituents and assess the in-vitro antidiarrhoeal activity of Gardenia arborea Roxb. leaves, specifically exploring the ethanolic extracts against common diarrhoea-causing pathogens, Escherichia coli and Staphylococcus aureus. Methods: Phytochemical profiling was conducted using high-resolution liquid chromatography-mass spectrometry (HR-LCMS), and the compounds were identified against the Metlin database. The antidiarrhoeal activity was evaluated through antibacterial assays, measuring zones of inhibition in millimetres, to determine the effectiveness of the extracts against the pathogens at various concentrations. Results: The HR-LCMS analysis identified several key compounds, including Isofraxidin, Arborinine, and Ustiloxin D, within the extracts. In vitro antidiarrhoeal tests demonstrated significant antibacterial activity. The ethanolic extract (GDET) at 500 µg/ml inhibited E. coli by 21.8±0.5 mm and S. aureus by 23.6±0.5 mm. The chloroform extract (GDCH) showed even greater efficacy, inhibiting E. coli by 24.2±0.6 mm and S. aureus by 25.7±0.7 mm, compared to the standard antibiotic ciprofloxacin, which inhibited E. coli by 25.8±0.3 mm and S. aureus by 26.4±0.6 mm at the same concentration. Conclusion: The findings confirm the potent antidiarrhoeal and antibacterial properties of Gardenia arborea Roxb., supporting its traditional use and potential development into a natural therapeutic agent for treating diarrhoea. The distinct phytochemical profile and the dose-dependent antibacterial activity emphasize the plant's utility in pharmacological applications.