The influence of Aspalathus linearis (Rooibos) and dihydrochalcones on adrenal steroidogenesis: Quantification of steroid intermediates and end products in H295R cells

► A single UPLC-MS/MS method was developed to quantify 21 steroid metabolites. ► Rooibos, aspalathin and nothofagin reduced basal H295R steroid production (P < 0.01). ► Rooibos reduced total steroid output (P < 0.001) in forskolin stimulated H295R cells. ► Rooibos decreased forskolin-stimulated glucocorticoid metabolites (P < 0.001). ► Human CYP11B1 catalyses the conversion of A4 to 11βOH-A4.