Comparative study of Passiflora taxa leaves: I. A morpho-anatomic profile

Determining the authenticity and quality of plant raw materials used in the formulation of herbal medicines, teas and cosmetics is essential to ensure their safety and efficacy for clinical use. Some Passiflora species are officially recognized in the pharmaceutical compendia of various countries and have therapeutic uses, particularly as sedatives and anxiolytics. However, the large number of Passiflora species, coupled with the fact that most species are popularly known as passion fruit, increases the misidentification problem. The purpose of this study is to make a pharmacognostic comparison between various Passiflora species to establish a morpho-anatomical profile that could contribute to the quality control of herbal drug products that contain passion fruit. This was conducted by collecting samples of leaves from twelve Passiflora taxa (ten species and two forms of P. edulis): P. actinia, P. alata, P. amethystina, P. capsularis, P. cincinnata, P. edulis f. flavicarpa, P. edulis f. edulis, P. incarnata, P. morifolia, P. urnifolia, P. coccinea and P. setacea, from different locations and their morpho-anatomical features were analyzed using optical microscopy and scanning electron microscopy. Microscopic analysis allowed to indicate a set of characters that can help to differentiate species. These include midrib and petiole shape, midrib and petiole vascular pattern, medium vein shape, presence of trichomes, presence of blade epidermal papillae and sclerenchymatic cells adjoining the vascular bundles. These characters could be used to assist in the determination of herbal drug quality and authenticity derived from a species of Passiflora