Heleno Dias Ferreira

Antifungal activity of volatile constituents of Eugenia dysenterica leaf oil

The essential oil from the hydrodistillation of Eugenia dysenterica leaves consisted mainly of beta-caryophyllene and alpha-humulene as the major sesquiterpene, while limonene and alpha-thujene were the major monoterpene hydrocarbons. The main oxygenated mono and sesquiterpene constituents were alpha-terpineol and beta-caryophyllene oxide, respectively. The oil was investigated against eight strains of Candida albicans, 35 strains of Cryptococcus neoformans var. neoformans, and two C. neoformans var. gattii isolated from HIV-infected individuals with candidosis or cryptococcal meningitis using the agar dilution method. Based on the minimal inhibitory concentration (MIC) values, the most significant results were obtained against Cryptococcus strains. It was observed that 22 strains were inhibited at a concentration of 250 microg/ml, whereas four exhibited potent inhibition with MIC values below 125 microg/ml against 10(6) UFC/ml organisms. We found MICs > or = 3.12 microg/ml for 91.6, 50 and 30% of all Cryptococcus strains in relation of amphotericin B, fluconazole and itraconazole, respectively.

Tannin composition of barbatimão species

A comparative study of tannin composition of three species known as barbatimão (Stryphnodendron adstringens, Stryphnodendron polyphyllum and Dimorphandra mollis) was developed by TLC, hydrolysis followed by PC, and colorimetry. Principal component analysis of the data obtained showed strong differentiation between the genus Dimorphandra and Stryphnodendron. Additionally, barks from the two Stryphnodendron sp. also presented considerable differences in the tannin structure.

Chemical variability in the essential oil of Hyptis suaveolens

The essential oils of Hyptis suaveolens plants collected from 11 localities of the Brazilian Cerrado region were investigated by GC-MS. Sabinene, limonene, biclyclogermacrene, beta-phellandrene and 1,8-cineole were the principal constituents. The results were submitted to principal component and chemometric cluster analysis which allowed three groups of essential oils to be distinguished with respect to the content of p-mentha-2,4(8)-diene, limonene/beta-phellandrene/gamma-terpinene and germacrene D/bicyclogermacrene. In patterns of geographic variation in essential oil composition indicated that the sesquiterpenes are mainly produced in the samples grown at lower latitudes.

Molluscicidal activity against Biomphalaria glabrata of Brazilian Cerrado medicinal plants

Alcoholic extracts of six Brazilian Cerrado medicinal plants were evaluated for their molluscicidal activity against Biomphalaria glabrata, intermediate host of schistosomiasis. Stryphnodendron polyphyllum bark extract, rich in condensed tannins, was the most promising as molluscicide.

Essential oil chemotypes in Hyptis suaveolens from Brazilian Cerrado

The composition of nine samples of essential oil of individual plants in fruiting stage of Hyptis suaveolens from Brazilian Cerrado was investigated by GC–MS. Spathulenol, 1,8-cineole and (E)-caryophyllene were the principal constituents. The results were submitted to Principal Component and Chemometric Cluster Analysis which allowed three groups of essential oils to be distinguished with respect to the content of 1,8-cineole/sabinene, β-bourbonene and α -bulnesene. Latitude seems to be the most important environmental factor influencing the oil contents. Pattern of geographic-variation in essential oil composition indicated that sesquiterpenes are mainly produced in the samples grown at lower latitudes and altitudes.  2002 Elsevier Science Ltd. All rights reserved.

Seasonal variation in the content of tannins in barks of barbatimão species

A composicao de taninos em cascas de especies de barbatimao, Stryphnodendron adstringens (Mart.) Cov. and S. polyphyllum (Mart.), foi analisada mensalmente durante um ano. Os resultados foram correlacionados com as condicoes climaticas do periodo de coleta (precipitacao, umidade e temperatura media) atraves de metodos quimiometricos. Analise de componentes principais dos dados mostrou uma tendencia de maior producao de taninos na estacao quente e chuvosa, sugerindo que os fatores ambientais podem afetar os teores de taninos nestas especies.

Estudo farmacognóstico das folhas de Pimenta pseudocaryophyllus (Gomes) L.R. Landrum - Myrtaceae

The goal of this research was to obtain quality control parameters for the identification of the plant drug of Pimenta pseudocaryophyllus (Gomes) L. R. Landrum that occurs in Brazilian savannah. So, two samples were collected, one in Minas Gerais state - Brazil, and the other one in Brasilia city - DF - Brazil, and the vouchers were deposited in the UFG Herbarium code number UFG-27159 and Ezechias Paulo Heringer Herbarium code number 21745-0, respectively. Part of the botanical material in both samples was prepared for microscopic analysis. The other one was air-dried, crushed to powder and used for phytochemical screening. The study has shown that P. pseudocaryophyllus leaves are hypostomatic, there are abundant unicellular trichomes in abaxial surface, there are secretory cavities with oily content and epidermal cells have thick wall. Tannins, phenolic compounds and flavonoids were detected in the phytochemical screening. The tannins had been quantified by different methods involving colorimetric and protein precipitation reactions, getting different results. This fact calls the attention for the necessity of specifying the method used together with the minimum tannins limit established. The results configure as important parameters for the quality control of the plant material and denote that the species in study take an important potential as herbal medicine that it deserves to be investigated in pharmacologic and toxicologic studies.

Chemical composition and antifungal activity of the essential oil of Hyptis ovalifolia Benth. (Lamiaceae)

The leaves of Hyptis ovalifolia Benth. (Lamiaceae) were subjected to hydrodistillation and the resulting volatiles were investigated by GC/MS. The main constituent representing 60% of the essential oil was isolated by column chromatography and identified by spectroscopic methods as (R)-6-[(Z)-1-heptenyl]-5,6-dihydro-2H-pyran-2-one (1). This compound showed strong in vitro activity against four dermatophyte fungi Microsporum canis, Microsporum gypseum, Tricophyton mentagrophytes, and Tricophyton rubrum (a total of 60 strains) with a minimal inhibitory concentration observed in the range of 125-7.8 mg µL-1.

Ocorrência e caracterização de galhas entomógenas em uma área de floresta estacional semidecídua em Goiânia, Goiás, Brasil

In an area of seasonal semideciduous forest situated on Campus Samambaia of the Universidade Federal de Goias in Goiânia, Goias 34 types of insect galls were collected during the period 2005-2007. The galls occurred in 20 species of plants from 12 families, with Leguminosae (9), Styracaceae (6) and Ulmaceae (4) having the greatest number of gall morphotypes. Leaf and stem galls were the most widespread. Concerning gall morphology, the following were collected: globoid, discoidal, ellipsoidal, cylindrical and conical. The colour varied from green to yellow, brown and red. The galls were isolated or grouped and glabrous or pilose. The principal inducers were Cecidomyiidae (Diptera) and the parasitoids found were of the families Eulophidae, Torymidae, Pteromalidae, Encyrtidae (Hymenoptera). This is the first report of galls in four species of host plants for the Neotropical region.

Flavonoides e atividade antioxidante em Palicourea rigida Kunth, Rubiaceae

The antioxidant activity, evaluated by DPPH (1,1-difenil-2-picrilidrazila) method, and the determination of the total phenolic compounds of the crude methanolic extract and fractions of the Palicourea rigida Kunth, Rubiaceae, leaves were quantified in this work. Despite weak activity exhibited by crude extract (500 ppm), the fraction ethyl acetate showed moderate activity (192 ppm), and the largest value for the phenolic compounds among all the assayed fractions. Then, the ethyl acetate fraction was submitted to the chromatography procedures which led to the isolation of the flavonoid quercetin 3-O-D-glicoside, quercetin 3-O-sophoroside and isorhamnetin 3-glicoside, which had the structures elucidated by spectroscopy analysis, including RMN (1D and 2D) and comparison with literature data.