Evidence on the inhibitory effect of Brassica plants against Acinetobacter baumannii lipases: phytochemical analysis, in vitro, and molecular docking studies

• DOI: 10.1186/s12906-024-04460-y
• Publication Date: 2024-04-19T10:01:45Z
• Authors: Manal M. Sabry; Ali M. El-Halawany; Walaa G. Fahmy; Basma M. Eltanany; Laura Pont; Fernando Benavente; Ahmed S. Attia; Farag F. Sherbiny; Rana M. Ibrahim
• Keywords: Acinetobacter baumannii; In Vitro Evaluation; Veterinary medicine; Phytochemicals; Docking (animal); Brassica; Phytochemical; Gram-Positive Bacteria; Microbiology; Biochemistry; Agricultural and Biological Sciences; Other systems of medicine; 03 medical and health sciences; In vitro; Tandem Mass Spectrometry; Gram-Negative Bacteria; Health Sciences; Genetics; Biology; Pharmacology; 0303 health sciences; Mass spectrometry; Bacteria; Research; Botany; Life Sciences; Lipase; Anti-Bacterial Agents; Therapeutic Potential of Berberine Alkaloids; Molecular Docking Simulation; Antimicrobial Properties of Essential Oils in Foods; Lipase inhibition; Computational Theory and Mathematics; FOS: Biological sciences; Computer Science; Physical Sciences; Pseudomonas aeruginosa; Medicine; Docking study; RZ201-999; Food Science; Computational Methods in Drug Discovery

Abstract Background Infections caused by Acinetobacter baumannii are becoming a rising public health problem due to its high degree of acquired and intrinsic resistance mechanisms. Bacterial lipases penetrate and damage host tissues, resulting in multiple infections. Because there are very few effective inhibitors of bacterial lipases, new alternatives for treating A. baumannii infections are urgently needed. In recent years, Brassica vegetables have received a lot of attention since their phytochemical compounds have been directly linked to diverse antimicrobial actions by inhibiting the growth of various Gram-positive and Gram-negative bacteria, yeast, and fungi. Despite their longstanding antibacterial history, there is currently a lack of scientific evidence to support their role in the management of infections caused by the nosocomial bacterium, A. baumannii. This study aimed to address this gap in knowledge by examining the antibacterial and lipase inhibitory effects of six commonly consumed Brassica greens, Chinese cabbage (CC), curly and Tuscan kale (CK and TK), red and green Pak choi (RP and GP), and Brussels sprouts (BR), against A. baumannii in relation to their chemical profiles.

Methods The secondary metabolites of the six extracts were identified using LC-QTOF-MS/MS analysis, and they were subsequently correlated with the lipase inhibitory activity using multivariate data analysis and molecular docking.

Results In total, 99 metabolites from various chemical classes were identified in the extracts. Hierarchical cluster analysis (HCA) and principal component analysis (PCA) revealed the chemical similarities and variabilities among the specimens, with glucosinolates and phenolic compounds being the major metabolites. RP and GP showed the highest antibacterial activity against A. baumannii, followed by CK. Additionally, four species showed a significant effect on the bacterial growth curves and demonstrated relevant inhibition of A. baumannii lipolytic activity. CK showed the greatest inhibition (26%), followed by RP (21%), GP (21%), and TK (15%). Orthogonal partial least squares-discriminant analysis (OPLS-DA) pinpointed 9 metabolites positively correlated with the observed bioactivities. Further, the biomarkers displayed good binding affinities towards lipase active sites ranging from −70.61 to −30.91 kcal/mol, compared to orlistat.

Conclusion This study emphasizes the significance of Brassica vegetables as a novel natural source of potential inhibitors of lipase from A. baumannii.