Phytochemical and morpho-anatomical study of the vegetative organs of Psychotria fractistipula L.B.Sm., R.M. Klein & Delprete (Rubiaceae)

Abstract

Psychotria fractistipula L.B.Sm, R.M. Klein & Delprete (Rubiaceae) is found in the existing Atlantic Forest in the South of Brazil, in the Paraná and Santa Catarina States. The members of Rubiaceae are characterized chemically by the presence of alkaloids, some pharmacological properties of which include antifungal, antibacterial, analgesic, antioxidant, antimutagenic, and antiviral activities. In this study, we report the results of anatomical, morphological, and histochemical analyses of the leaves and stems of the Rubiaceae family member, P. fractistipula. The anatomical analysis involved of light microscopy and scanning electron microscopy. Morpho-anatomical and histochemical characterization were made using standard methodology. The isolated compounds were identified by Nuclear Magnetic Resonance spectroscopic analysis. The following structures are highlighted as the distinctive features of the species: presence of petiolate leaves and a petiole base, leaf blade with smooth cuticle on both surfaces, paracytic stomata, and, dorsiventral mesophyll and presence of trichomes on the leaves and stems. Phytosteroids, identified as β-sitosterol and campesterol, were observed in the hexane fraction of the stem. Future studies should focus on the isolation of other fractions of interest and their characterization through specific biological and cytotoxicity assays.

Notes on the Newly Identified Asperula cankiriense B. Şahin & Sağıroğlu (Rubiaceae) from Turkey Based on a Light and Scanning Electron Microscopic Study

“…The observation of multilayered collenchyma cells in the transverse section of the A. cankiriense leaf suppors a previous study by Metcalfe & Chalk (1950). Oliveira et al (2020) reported that the stem was oval in shape and the presence of multi-row collenchyma in the cortex layer under the epidermis as in A. cankiriense in their morpho-anatomical study on the vegetative organs of Psychotria fractistipula L.B.Sm., R.M. Klein & Delprete belonging to the Rubiaceae family.…”

“…Klein & Delprete belonging to the Rubiaceae family. The vascular cylinder at A. cankiriense stem has xylem and external phloem, following the stem shape, but Oliveira et al (2020) reported the presence of a second phloem in addition to the internal xylem and external phloem in the P. fractistipula stem. The stems of A. cankiriense and Rubia tinctorum L. show similar features, with the cortex being composed of multilayered parenchyma cells under the epidermis and the vascular tissue being in collateral vascular bundles (Arı & Kahraman, 2020).…”