Influence of Vermicompost Tea on Metabolic Profile of Diplotaxis muralis: An NMR Spectroscopic Analysis

Recently, we reported the efficacy of organic nutrient solutions in supporting the hydroponic cultivation of Diplotaxis muralis. The aim of this study was to elucidate the influence of standard and enhanced vermitea formulations, compared to the conventional Hoagland solution, on phytochemical and metabolomic changes in D. muralis. Using NMR-based metabolomics and multivariate analysis, we observed significant metabolite variation among treatments. Both vermitea formulations increased the levels of acetate, alanine, and 2-oxoglutarate, and boosted the biosynthesis of key secondary metabolites, including methoxy flavonoids and glucosinolates. The standard vermitea treatment further resulted in a higher accumulation of leucine and citrate, while the Hoagland solution induced higher glucose concentrations. Enhanced vermitea improved copper and zinc uptake, positively correlating with methoxy flavonoid production. In contrast, the higher phosphorus and potassium content of the Hoagland solution correlated with increased glucose levels in D. muralis. Metabolite profiling coupled with multivariate analysis identified the enhanced vermitea as the best alternative to chemical nutrient solution for improving the nutritional and phytochemical quality of D. muralis leaves.