Physicochemical properties, chemical composition, and against Klebsiella pneumoniae mechanism of Scrophularia ningpoensis honey

Scrophularia ningpoensis honey (SNH) is a type of honey derived from a traditional Chinese medicinal plant, with considerable potential value. Klebsiella pneumoniae , one of the most threatening pathogens worldwide, is also among the leading causative agents of wound infections, postoperative complications, and trauma-related skin and soft tissue infections. However, research on SNH remains limited, particularly regarding its compound composition and its ability to combat K. pneumoniae . In this study, the physicochemical properties of SNH were comprehensively characterised, revealing its high quality. SNH also demonstrated superior antibacterial activity compared to seven other types of honey. Furthermore, pathways such as valine, leucine, and isoleucine biosynthesis, as well as pantothenate and CoA biosynthesis, have been found to contribute to the antibacterial activity of SNH. To identify the active constituents, SNH was sequentially extracted with solvents of varying polarities and analyzed by UPLC-MS/MS, resulting in the identification of 157 metabolites. Among them, chlorogenic acid and chrysin were identified as potential key compounds responsible for the antibacterial effects against K. pneumoniae . This study systematically elucidated, for the first time, the physicochemical characteristics and chemical composition of SNH and demonstrated its strong antibacterial properties, providing an experimental basis for its further development and application.