Tecoma stans: Alkaloid Profile and Antimicrobial Activity

Area of Science:

• Pharmacology
• Natural Products Chemistry
• Microbiology

Background:

• Tecoma stans (L.) Kunth, a Bignoniaceae family plant, is recognized for its medicinal potential.
• Understanding the antimicrobial activity of T. stans leaf extract and its active compounds is crucial for drug discovery.

Purpose of the Study:

• To evaluate the antibacterial and antifungal activities of Tecoma stans methanolic leaf extract (TSME).
• To identify and characterize the phytoconstituents responsible for the observed antimicrobial effects.
• To elucidate the potential mechanism of action through molecular docking studies.

Main Methods:

• Antimicrobial activity was assessed using the agar diffusion method.
• Alkaloids were isolated via silica gel column chromatography and identified using nuclear magnetic resonance (NMR) spectroscopy.
• Molecular docking was performed against MurD ligase, penicillin-binding protein, and dihydropteroate synthase.

Main Results:

• TSME demonstrated significant broad-spectrum antibacterial activity, with minimum inhibitory concentrations (MICs) comparable to ampicillin and gentamicin.
• Promising antifungal activity was observed against Aspergillus flavus and Candida albicans, with MICs lower than amphotericin.
• Four alkaloids, tecostanine, 4-OH tecomanine, 5-hydroxyskytanthine, and tecomanine, were isolated and identified.
• Molecular docking indicated that the isolated alkaloids effectively bind to the MurD ligase enzyme, suggesting a mechanism of action.

Conclusions:

• Tecoma stans methanolic leaf extract possesses significant antimicrobial potential.
• The identified alkaloids, particularly their interaction with MurD ligase, offer a promising basis for developing new antimicrobial agents.
• T. stans alkaloids could serve as a scaffold for novel, powerful antimicrobial drug development.