Quantification of vitamin D3 and its hydroxylated metabolites in waxy leaf nightshade (Solanum glaucophyllum Desf.), tomato (Solanum lycopersicum L.) and bell pepper (Capsicum annuum L.)

Changes in vitamin D3 and its metabolites were investigated following UVB- and heat-treatment in the leaves of Solanum glaucophyllum Desf., Solanum lycopersicum L. and Capsicum annuum L. The analytical method used was a sensitive and selective liquid chromatography electrospray ionisation tandem mass spectrometry (LC–ESI-MS/MS) method including Diels–Alder derivatisation. Vitamin D3 and 25-hydroxy vitamin D3 were found in the leaves of all plants after UVB-treatment. S. glaucophyllum had the highest content, 200 ng vitamin D3/g dry weight and 31 ng 25-hydroxy vitamin D3/g dry weight, and was the only plant that also contained 1,25 dihydroxy vitamin D3 in both free (32 ng/g dry weight) and glycosylated form (17 ng/g dry weight).