Phytochemical Profiling and Anti‐VanA Activity of Pulegone Extracted from Ziziphora tenuior Flower Against Vancomycin‐Resistant Enterococci: an In Silico Approach

Abstract

Ziziphora tenuior is a herb known for its potent pharmaceutical activities. However, the specific compounds of the flowers of this herb have not been fully studied yet. This study used GC‐MS to conduct a chemical analysis of the methanol and dichloromethane extracts of Z. tenuior flowers. Additionally, it sought to assess the potential antibacterial activity of the extracts against vancomycin‐resistant enterococci (VRE) bacteria by predicting the interactions between one of the most prevalent compounds in the extracts and the D‐alanyl‐D‐lactate ligase (VanA) protein, which is responsible for enterococci resistant to vancomycin. The results revealed a total of 15 compounds in the methanolic extract and 12 compounds in the dichloromethane extract. Among these, 5‐methyl‐2‐(1‐methylethylidene)‐cyclohexanone, also known as pulegone, constituting 52.6 % of the methanolic extract and 34.6 % of the dichloromethane extract, was the most abundant compound in the extracts. Furthermore, the in‐silico analysis demonstrated that pulegone exhibited significant interactions with VanA, as indicated by docking energy values of −7 kcal/mol and the formation of one hydrogen bond. The study suggests that pulegone shows promise as an antibacterial agent against VRE by potentially interacting with VanA protein and serving as a key inhibitor in fighting vancomycin resistance.