Ernane Ronie Martins

Atividade antimicrobiana de extratos hidroalcoolicos das folhas de alecrim- pimenta, aroeira, barbatimão, erva baleeira e do farelo da casca de pequi

This study evaluated the phytochemical profile of standardized hydroalcoholic extracts (EAPs) obtained from leafs of rosemary (Lippia sidoides), peppertree (Myracrodruon urundeuva), barbatimao (Stryphnodendron adstringens), erva baleeira (Cordia verbenacea) and from the meal of pequi fruit peel (Caryocar brasiliense) and the activity of different levels of these EAPs against Staphylococcus aureus and Escherichia coli. After collection and identification of the species, plant leaves and pequi peel were separated to prepare the EAPs. The EAPs underwent phytochemical screening. The antimicrobial activity of the EAPs at different dilutions (200, 300, 400 and 500mg mL-1) was tested using the disk diffusion method. The phytochemical screening detected components with antimicrobial potential in the EAPs tested. The disk diffusion test showed that peppertree (≥200mg mL-1), barbatimao (≥300mg mL-1) and erva-baleeira (≥400mg mL-1) extracts inhibited S. aureus growth, but not E. coli development. The EAPs did not affect E. coli development, but the leaves from peppertree, barbatimao and erva-baleeira exhibited potential to inhibit S. aureus growth. The leaves and bark of the studied plants may consist in a sustainable, affordable and feasible alternative to treat microbial infections.

A quantitative assessment of genetic erosion in ipecac (Psychotria ipecacuanha)

In this study, we present a methodology by which the threat of genetic erosion to a wild plant species growing in a given geographic region can be assessed in a quantitative manner. Evaluation of threat is carried out by scoring a checklist based on information about the ecosystem and the target species. This approach was used to assess the threat of genetic erosion faced by ipecac (Psychotria ipecacuanha), an endangered medicinal plant that is native to the Atlantic Rain Forest of southeastern Brazil. An analysis of the spatial distribution of 20 risk factors over 14 forest fragments indicated that the threat of genetic erosion is not uniformly distributed over the region. The most endangered clusters of ipecac are facing presently a threat almost three times larger than that faced by the least endangered.We were able to identify the short distance of a forest fragment to the major population centres and thepoor conservation status of the species as the factors that present the major contribution to threat. The distance of a forest fragment to new development projects, the extent of the use of a wild habitat within a forest fragment, and the susceptibility of target species to grazing animals were considered the least important factors of risk. The results obtained by using this approach allowed us to formulate an itemized description of which category of forest fragments we should direct forthcoming expeditions with the aim of collecting germplasm of wild ipecac.

Effects of Anacardium humile leaf extracts on the development of gastrointestinal nematode larvae of sheep

The rapid development of nematode resistance to anthelmintics has limited the success of small ruminant gastrointestinal helminthiasis control in several countries, stimulating the search for alternatives. The aim of this work was to evaluate the in vitro anthelmintic activity of Anacardium humile (Anacardiaceae) on gastrointestinal nematodes of sheep. Aqueous and ethanolic extracts of A. humile leaves were evaluated by the larval development inhibition assay at concentrations of: 187.5, 150, 100, 50, and 30 mg ml(-1); and 100, 80, 60, 40, and 20 mg ml(-1), respectively. Phytochemical analysis demonstrated the presence of tannins, flavenoids, and alkaloids in the leaves. The LD(50) was 10.14 mg ml(-1) for the aqueous extract and 23.24 mg ml(-1) for the ethanolic extract, providing evidence for the potential of this plant in the endoparasite control.

Chemical study and larvicidal activity against Aedes aegypti of essential oil of Piper aduncum L. (Piperaceae)

Piper aduncum L. is used in folk medicine to treat respiratory and inflammatory diseases. The aim of this study was to analyze the essential oil from leaves of P. aduncum collected in the Brazilian Cerrado, North of Minas Gerais, as well as to evaluate the larvicidal activity of this oil and of its major constituent. The essential oil was analyzed by gas chromatography coupled to flame ionization detector and gas chromatography coupled to mass spectrometry that allowed characterizing 23 compounds (monoterpenes: 90.4%; sesquiterpenes: 7.0%). The major component was 1,8-cineole (53.9%). This oil showed to be very different from those obtained from the same species. Larvae of A. aegypti were exposed to different concentrations of the essential oil and 1,8-cineole. The mortality rate of 100% was obtained after 24 h of treatment with the oil at concentrations of 500 and 1,000 ppm. After 48 h of treatment, the mortality rate was 80% and 50% for concentrations of 250 and 100 ppm, respectively. The LC₅₀ obtained after 24h was estimated in 289.9 ppm and after 48 h was 134.1 ppm. The major compound 1,8-cineole showed no larvicidal activity.

Comprimento da estaca no desenvolvimento de mudas de alecrim-pimenta

This research aimed to evaluate the effect of shoot cutting length on the development of pepper-rosmarin seedlings (Lippia sidoides Cham.). The cuttings were obtained from stock plants of the medicinal vegetable garden of Instituto de Ciencias Agrarias/UFMG, Montes Claros, Minas Gerais, Brazil. The experiment was conducted in greenhouse conditions with intermittent mist. The experimental design was totally randomized with four treatments consisted of different size intervals (5 to 8cm, 8.1 to 11cm, 11.1 to 14cm and 14.1 to 17cm), with five replications each. The amount of shooting and root, the shooting and root dry weight (g), the the longest root length (cm), the visual rooting evaluation and the rooting percentage were analysed. The results indicated that cutting length affects the development of pepper-rosmarin seedlings, especially shooting and root dry weight. The cuttings with 14.1 until 17cm presented the highest percentage of rooting and the largest average of the other variables, being the most recommended to be used in the propagation of pepper-rosmarin.

Effect of harvesting time on phytomass production and essential oil yield in 'alecrim-pimenta' (Lippia sidoides Cham.)

O objetivo do estudo foi avaliar a massa fresca, massa seca e rendimento de oleo essencial de Lippia sidoides cultivada no Norte de Minas. O delineamento foi em blocos ao acaso, com quatro tratamentos e cinco repeticoes. Os tratamentos foram constituidos por intervalos de colheita: 120, 180, 240, 300 e 360 dias apos o transplantio. Em cada colheita, foram determinados a altura das plantas, o diâmetro da base do caule, o rendimento de materia fresca de folhas, caule, parte aerea e o rendimento de materia seca da parte aerea, alem do teor e rendimento de oleo essencial por planta. O teor maximo de oleo essencial foi detectado aos 180 dias, enquanto que a producao maxima de materia seca ocorreu aos 329 dias. A producao de oleo essencial por planta foi 2,34±1,15 g. A produtividade de oleo essencial foi de 124,8 kg ha-1, sendo recomendada a colheita aos 180 dias.

Toxicidade aguda dos extratos hidroalcoólicos das folhas de alecrim-pimenta, aroeira e barbatimão e do farelo da casca de pequi administrados por via intraperitoneal

This study aimed to conductpre-clinical toxicology testing to investigate the toxicity of Lippia sidoides Cham., Myracrodruon urundeuva Fr. All., Stryphnodendron adstringens (Mart.) Coville and Caryocar brasiliense Camb., by determining the 50% (LDL50) lethal dose. In the investigation of the LD50, groups of Swiss mice of the same sex were used (n=150; 30 animals per plant and all inoculated intraperitoneally with serial dilutions of the aqueous fraction obtained from the leaves of plants. After inoculation, the animals were observed along a period of 14 days in order to observe the dead, sick and survivors rate. In mice inoculated intraperitoneally, the acute pre-clinical toxicology testing demonstrated toxicity equal to 0,31mg mL-1 LD50 mL-1 for all plants. The exception was for Stryphnodendron adstringens, which presented toxicity equal to a 0,25mg mL-1DL50 mL-1 and values expressed in terms of dilution. Research should be conducted to obtain data on toxicity of the plants in other ways to ensure the use in human and animal health. Therefore, the studied plants should be used with caution. They present a relatively mild toxic potential, but it may be harmful to users if they are not properly utilized.

Growth study and essential oil analysis of Piper aduncum from two sites of Cerrado biome of Minas Gerais State, Brazil

Piper aduncum L., Piperaceae, stands out due to its biological activities, however, it is still found in the wild and little is known about its agronomic point of view. The aim of this study was to evaluate the growth and to analyze the chemical composition of essential oils from leaves of P. aduncum collected in two different sites of Cerrado as well as in cultivated plants. The cultivation was installed out in a greenhouse using cuttings of adult specimens. Essential oils were obtained from fresh leaves. Plants from the two studied locations showed erect growth habit and behavior of linear growth. The essential oils composition of P. aduncum from Bocaiuva did not differ between wild and cultivated plants, as the major substance identified as 1,8-cineole. The plants from Montes Claros site showed a distinct concentration for the two samples, being the major substance characterized as transocimene (13.4%) for wild and 1,8-cineole (31.3%) for cultivated plants. Samples from both locations showed a similar essential oil composition in cultivars. Our results showed that P. aduncum cultivation is feasible and the variation in chemical composition of the two sites may indicate an environmental influence, since chemical and isoenzyme analysis did not show great differences.

Molecular phylogeography of Carapichea ipecacuanha, an amphitropical shrub that occurs in the understory of both semideciduous and evergreen forests.

The medicinal shrub Carapichea ipecacuanha (ipecac) is an amphitropic species with three disjunct areas of distribution. In the Brazilian Atlantic and Amazonian ranges, the species was associated mostly with the understory of seasonal semideciduous forests, whereas in the Central American–Colombian range, the species occurred in the understory of moist evergreen forests. We examined the phylogeographic structure of ipecac using chloroplast trnT‐trnL and nuclear internal transcribed spacer (ITS) sequences from 120 and 46 specimens, respectively. To complement existing data on root alkaloid profiles, we used high‐performance liquid chromatography to assess the levels of emetine and cephaeline in 33 specimens from the two Brazilian ranges. The three ranges shared neither nuclear nor chloroplast haplotypes. The phylogeographic structures showed an uneven distribution of genetic diversity, sharp breaks and high levels of genetic differentiation among ranges. Our results suggest that the extant populations are descendents of at least four distinct ancestral lineages. The Atlantic ipecacs showed higher levels of genetic diversity than ipecacs from the other two ranges; it is likely that they derive from two ancestral lineages, with long‐term persistence in that region. The Amazonian ipecacs were monomorphic with respect to the ITS and cpDNA sequences, which supports the view that there was a recent expansion from a single parental source after a strong genetic bottleneck. The existence of a fourth distinct lineage is apparent from the high levels of genetic and chemical differentiation that we identified in the Central American–Columbian ipecacs.

Reproductive studies on ipecac (Cephaelis ipecacuanha (Brot.) A. Rich; Rubiaceae): meiotic behavior and pollen viability

Reproductive studies were carried out on Brazilian accessions of ipecac, Cephaelis ipecacuanha. Meiotic behavior was studied using the squashing technique. Irregular chromosome segregation in meiosis I and II, many sets of chromosomes in telophase II, micronuclei, incorrect cytoplasm division, incomplete cytokinesis and anomalous post-meiotic products, mainly polyads, were observed. The mean meiotic index was lower than 72%. Pollen viability was analyzed using Alexander solution, and the percentages ranged between brevistylous and longistylous floral morphs (85.3 to 93.1%), and among different localities (82.5 to 92.6%) analyzed. The size of pollen ranged between viable and sterile, and empty and shrunken sterile. In its natural habitat, this species is known to propagate by vegetative multiplication, but sexual reproduction seems to be as important as the vegetative propagation to this species.