Anatomical characters and chemical profile of leaves of three species in Lauraceae family

Abstract

The Lauraceae family is widely distributed in tropical and subtropical climates, has more than 2500 species and in the taxonomic point of view, it is one of the most difficult families to identify species. The aim of this study was to analyze the leaf anatomy of three species of Lauraceae (Ocotea indecora (Schott) Mez, Nectandra barbellata Coe-Teix. and Endlicheria paniculata (Spreng.) J.F.Macbr.) and identify the chemical profile of essential oil extracted from the leaves by hydrodistillation method. The leaves of the three species were obtained in Parque Estadual Intervales, Atlantic Forest, Sao Paulo state, Brazil. Samples of leaves were fixed, dehydrated, embedded in synthetic resin and sectioned for mounting histological slides for anatomical description of leaf tissues. The essential oil extracted by hydrodistillation method from dried leaves was analyzed by gas chromatography to establish its chemical profile. The leaves are hypostomatic, the epidermis in E. paniculata and N. barbellata present regular cells walls and irregular cells walls in O. indecora in both sides of epidermis. The three species present a dorsiventral mesophyll. Histochemical analyses presented lipid substances in secretory cavity and cuticle; starch, phenolic compounds and mucilage were observed in parenchyma cells of midrib and mesophyll. Ultra structural analyses demonstrated that trichomes in the species E. paniculata and O. indecora are shown only on the abaxial leaf face and species N. barbellata presented trichomes on both sides of the epidermis (abaxial and adaxial). Ocotea indecora essential oil revealed as main compound the bicyclogermacrene and N. barbellata the 8-cadinene. The species showed different morphological characters and different compounds of the essential oil, being these data useful for the differentiation of the species. (C) 2018 Sociedade Brasileira de Farmacognosia. Published by Elsevier Editora Ltda. This is an open access article under the CC BY-NC-ND license.