ABSTRACT
Abstract Myrciaria glomerata O. Berg., Myrtaceae, popularly known as "cabeludinha", has high content of ascorbic acid and anti-inflammatory property and is used in folk medicine. The objectives of this study were the morphological, anatomical and histochemical characterization of the leaves. Leaf studies were made with optical, scanning electron and confocal microscopy. The collection of botanical material was held at the Tijuca Forest, Rio de Janeiro, RJ. Histochemical tests aimed the identification of lipids, starch grains, phenolic compounds and crystals. The leaves are simple, opposite, lanceolate, pinnate, hairy, with involute margins, hypostomatic and dorsiventral. The stomata are anomocytic. The epidermis presents simple trichomes. Epidermal cells show uneven thickening of their periclinal outer walls, mainly on the adaxial side of the leaf. Secretory cavities of essential oils are subepidermal and exceed, in height, the palisade parenchyma, formed by one cell layer. Four to five cellular layers, rich in phenolic compounds and lipids form the spongy parenchyma. The bundles are collateral and there are many crystals of calcium oxalate spread throughout the mesophyll. In the midrib and petiole the bundles are bicollateral. Analysis by scanning electron revealed epicuticular wax rod-shaped and as grains. In confocal microscopy, the adaxial epidermis, the fibers and the secretory epithelium of the cavities show autofluorescence. The data obtained are important in quality control exams of samples of this species.
ABSTRACT
Foi feito o estudo anatômico da folha de Eugenia florida DC., espécie arbórea da família Myrtaceae, coletada no Campus da Fundação Oswaldo Cruz, Rio de Janeiro, RJ. A espécie apresenta importantes propriedades farmacológicas, incluindo-se atividade antiviral. O presente estudo teve como objetivo fornecer dados, revelados através da microscopia óptica e da microscopia eletrônica de varredura, que possam contribuir para o conhecimento da espécie e, conseqüentemente, para a segurança em sua identificação. Anatomicamente, a folha é hipostomática, com organização dorsiventral do mesofilo. Apresenta tricomas simples apenas sobre a nervura mediana da face adaxial. As células epidérmicas apresentam contorno sinuoso em vista frontal e cutícula estriada. O parênquima paliçádico destaca-se pela grande quantidade de cristais prismáticos de oxalato de cálcio. Em posição subepidérmica ocorrem cavidades secretoras de óleos essenciais, pouco numerosas, nas duas faces da lâmina foliar. As células epidérmicas situadas sobre as estruturas secretoras constituem característica de valor diagnóstico e são reconhecíveis pela célula de topo, que é reniforme, circundada pelas adjacentes, que apresentam disposição radiada. A comparação entre folhas de sol e de sombra revela que, nas primeiras, as estruturas secretoras são completamente diferenciadas, ao contrário das folhas de sombra, além de apresentarem maior concentração de compostos ergásticos.
A study of the foliar anatomy of Eugenia florida DC., a tree of Myrtaceae family collected at Fundação Oswaldo Cruz, Rio de Janeiro, RJ, was accomplished. This species presents important pharmacological properties, including antiviral activity. The aim of this research was to furnish data, revealed by optical microscopy and scanning electronically microscopy, in order to contribute to the knowledge of the species and to its safe identification. Anatomically, the leaf is hipostomatic, with dorsiventral mesophyll. Simple unicellular hairs are present only on the adaxial side of the leaf in the midvein region. Anticlinal walls of epidermal cells are undulate and the cuticle is striate. Palisade parenchyma presents a large amount of prismatic oxalate crystals. In subepidermical position there are secretory cavities bearing ethereal oils. These structures occur in a low frequency and are scattered along the both sides of the foliar blade. The epidermal cells that overlap the secretory cavities form an important characteristic anatomical feature. They are recognizable by the top cell, which presents a kidney shape surrounded by cells in a radiate way. The comparison between sun and shade leaves shows a complete development of the secretory cavities and a higher concentration of ergastic compounds in the first ones.
ABSTRACT
O presente trabalho apresenta a anatomia foliar de Eugenia brasiliensis Lam., cujo óleo essencial possui propriedades anti-reumática, diurética, anti-inflamatória, além de ser ativo contra o Tripanosoma cruzi. O estudo foi feito, comparando-se folhas coletadas em áreas de restinga e de floresta, registrando-se as diferenças estruturais resultantes da influência dos fatores ambientais. Anatomicamente, a folha de E. brasiliensis é hipostomática, glabra, dorsiventral, com tendência à isobilateralidade. A epiderme apresenta notável espessamento da cutícula e seus estratos. Em posição subepidérmica, ocorrem numerosas cavidades secretoras de óleos essenciais, nas duas faces da lâmina foliar. No parênquima lacunoso situam-se drusas de oxalato de cálcio. As folhas provenientes da restinga apresentam, em relação àquelas coletadas na floresta, maior quantidade de estruturas secretoras de óleos essenciais, maior concentração de substâncias ergásticas, maior espessamento da cutícula e da lâmina foliar, maior quantidade de estômatos, mesofilo mais compacto, fibras esclerenquimáticas e elementos xilemáticos com maior grau de lignificação e maior densidade da rede vascular. Os dados obtidos são indicativos que a escolha do local de coleta de E. brasiliensis é relevante, tendo em vista que, na área da restinga, observa-se maior produção de óleos essenciais e demais substâncias associadas aos seus efeitos terapêuticos.
The present paper presents the foliar anatomy of Eugenia brasiliensis Lam. The essential oils produced by this species present anti-reumathic, diuretic and anti-inflammatory properties and show activity against Tripanosoma cruzi. This study was carried out by comparison between leaves developed in restinga and forest areas, in order to register the main differences in the structure of this organ related to environmental conditions. Anatomically, the leaf of E. brasiliensis is hipostomatic, glabrous, with dorsiventral mesophyll, whit tendency towards the isobilateral type. Thickness of the cuticle and cutinized wall is noteworthy. In sub-epidermical position, there are many secretory cavities that produce essential oils, in both sides of the foliar blade. In the spongy parenchyma there are calcium oxalate druses crystals. E. brasiliensis leaves developed in restinga area present, in relation to that proceeding from forest, a larger amount of secretory structures, a higher ergastic substances concentration, thicker cuticle and foliar blade, more abundant stomata, a more compact mesophyll, sclerenchyma fibers and xilem elements with a deeper lignification and a greater development of the vascular system. The data obtained in this research suggest that the choice of the area where E. brasiliensis should be collected is important, because in restinga area it presents a greater production of essential oils and other substances associated with therapeutic effects.