A Quantitative Morphological Analysis of Some Hypericum Species

Abstract

Hypericum perforatum L. (Hypericaceae) is a medicinal plant of considerable interest for the therapeutic potentialities of its biologically active compounds. Due to the presence of hybrids and frequent adulterants from other species of Hypericum, the identification of the drug obtained of this species is difficult. Therefore, a quantitative morphological analysis of the leaf epidermises of H. hircinum L. and H. perfoliatum L. compared with H. perforatum L., carried out by means of scanning electron microscopy and image analysis, was performed to identify phytognostic markers useful for the characterization of these different Hypericum species. Size and shape parameters of the leaf surface cells have permitted a comparative study of the cogeneric species examined, providing a key factor in their recognition and/or selection. Unlike the methods employed so far, the results obtained by means of this innovative kind of analysis supply a valid criterion, not only for the morphological differentiation of the Italian Hypericum species studied, but also for an accurate and reproducible quality control of the commercial samples, often made up of drugs obtained from different species, subspecies and varieties.