Simple high-performance liquid chromatography method for a-tocopherol measurement in Rosmarinus officinalis leaves q New data on a-tocopherol content

Abstract

A simple HPLC method for vitamin E (a-tocopherol) measurement in the leaves of Rosmarinus officinalis has been developed and validated. It has enabled new data for a-tocopherol content to be established. The leaves, recently harvested, were dried in a microwave oven and crushed; then, a-tocopherol was directly extracted from portions of ground material with acetone, by probe sonication. After centrifugation the acetonic extract was analysed by HPLC with ergocalciferol (vitamin D ) added as internal standard and a gradient elution with a Nucleosil C column at 358C.Validation parameters of 2 18 the method can be considered adequate. For standards: linearity is r50.999, recovery is 10062%, intra-assay precision has RSD563% and inter-assay precision has RSD566%. For samples: linearity is r50.99, recovery: 9367%, intra-assay precision has RSD564% and inter-assay precision has RSD567%.