Characterization saprobic fungi on leaf litter of two species of trees in the Atlantic Forest, Brazil

Abstract We investigated the composition and structure of fungal communities associated with leaf litter generated by Clusia nemorosa and Vismia guianensis that belong to phylogenetically-related botanical families and exist together in a remnant of the Atlantic Forest in Bahia, Brazil. Samplings were conducted during wet (June 2011) and dry (January 2013) seasons in Serra da Jibóia. The fungi were isolated using particle filtration and the 1,832 isolates represented 92 taxa. The wet season yielded the largest number of isolates (1,141) and taxa (76) compared with the dry season (641 isolates and 37 taxa). The richness and diversity of fungal species associated with C. nemorosa (64 taxa, Simpson=0.95)were higher compared with those of V.guianensis (59 taxa, Simpson =0.90). Analysis of similarity (ANOSIM) revealed significant variations in the composition and community structure of fungi isolated from the two plants as a function of seasons. In contrast, nonmetric multidimensional scaling (NMDS) analysis show that the seasonality was an important influence on the distribution of fungal species. However, the populations of the saprobic fungal communities were dynamic, and several factors may influence such communities in the Atlantic Forest.

Estudo farmacobotânico das folhas de Garcinia brasiliensis Mart. (Clusiaceae) / Pharmacobotanical studies of Garcinia brasiliensis Mart. (Clusiaceae) leaves

A espécie Garcinia brasiliensis Mart. (Clusiaceae), nativa da região Amazônica e cultivada em todo o território brasileiro, vem sendo bastante estudada devido seu potencial farmacológico, porém são escassos estudos que tratam da caracterização farmacobotânica desta espécie. Considerando as propriedades terapêuticas para tornar-se um medicamento fitoterápico, o presente trabalho teve como objetivos estudar a anatomia e histoquímica da folha e do pecíolo e elaborar dados macroscópicos e microscópicos que forneçam características marcantes para sua identificação além de dar subsídios para a análise farmacognóstica no controle de qualidade da droga vegetal. O material vegetal foi fixado e submetido às técnicas usuais de microscopia de luz e a testes histoquímicos. As folhas de G. brasiliensis são opostas, simples, descolores, forma elíptica com nervação peninérvia. As células epidérmicas, em vista frontal, apresentam contorno sinuoso e estômatos paracíticos somente na face abaxial. O mesofilo é dorsiventral, a nervura central apresenta contorno biconvexo e feixe vascular em forma de semi-arco fechado envolto por bainha esclerenquimática. Inclusões inorgânicas de cristais na forma de drusas e orgânicas representadas por compostos fenólicos e grãos de amidos estão dispersos ao longo de toda lâmina foliar e pecíolo. Observa-se com frequência a presença de canais secretores preenchidos por um conteúdo lipídico dispersos pelo parênquima fundamental e próximos aos feixes vasculares. Estes dados fornecem subsídios para o controle de qualidade da matéria-prima utilizada para a produção de fitoterápicos.

The Garcinia brasiliensis Mart. (Clusiaceae) species, native of the Amazon region and cultivated throughout the Brazilian territory, has been widely studied due to its pharmacological potential, but there are few studies dealing with the pharmacobotanic characterization of this species. Considering the therapeutic properties in order to become an herbal medicine, the present paper had the purpose of studying the anatomical and histochemical characterization of the leaf and petiole, as well as producing macroscopic and microscopic data that provide important characteristics for its identification, in addition to providing subsidies for the pharmacognostical analysis in order to offer elements for the quality assurance of the drug. The botanical material was prepared through the usual optical and histochemical microtechniques. The leaves of G. brasiliensis are simple, opposed, colorless, and they show an elliptical shape. As seen from the front, the epidermal cells have a sinuous contour, and paracytic stomata occur on the low surface. The leaves are hipostomatic and dorsiventral with heterogeneous mesophile. The mesophile is dorsiventral, the central midrib shows a biconvex contour and vascular system in a semi-closed arch shape surrounded by a sclerenchymatic sheath. Inorganic inclusions of crystals in the shape of druses, and organic inclusions represented by phenolic compounds and starch grains are found throughout the leaf blade and petiole. It is common to find secretory canals filled with a lipid content dispersed throughout the parenchyma and near the vascular bundles. These data support the quality assurance of the elements used to produce herbal medicines.

Antibacterial and cytotoxic activity of Brazilian plant extracts - Clusiaceae

Twelve extracts obtained from nine plants belonging to six different genera of Clusiaceae were analyzed against Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus and Enterococcus faecalis) bacteria using the microdilution broth assay. Tovomita aff. longifolia, T. brasiliensis, Clusia columnaris, Garcinia madruno, Haploclathra paniculata, and Caraipa grandifolia extracts showed significant results against the bacteria. The organic extract obtained from the leaves of T. aff. longifolia showed minimal inhibitory concentration (MIC) = 70 µg/ml and minimal bactericidal concentration (MBC) = 90 µg/ml against E. faecalis and the organic extract made with the stem of C. columnaris showed MIC = 180 µg/ml and MBC = 270 µg/ml against P. aeruginosa. None of the antibacterial extracts showed lethal activity against brine shrimp nauplii. On the other hand, both aqueous and organic extracts obtained from the aerial organs of Vismia guianensis that were cytotoxic to brine shrimp nauplii did not show a significant antibacterial activity in the assay.