Artigos Publicados
Acrocomia emensis (Arecaceae) genetic structure and diversity using SSR molecular markers (2016)
Abstract:
Acrocomia emensis, popularly known as the creeping tucum, belongs to the family Arecaceae, and is an oilseed specie of the Brazilian Savannah. The expansion of agricultural activity has rapidly destroyed its natural habitat, leading to a decrease in its population size. Genetic studies can be used to investigate the genetic variability, and may assist with the charting future conservation strategies. In this study the genetic diversity and structure of 150 individuals sampled in three locations in Minas Gerais were analysed, based on the transferability of six microsatellite markers, previously developed for A. aculeata. The results indicate that the populations studied have low levels of genetic variability (Ho = 0.148) and high, positive and significant inbreeding coefficient, indicating an excess of homozygotes. The average heterozygosity within the population (Hs = 0.700) accounted for 95.03% of the total genetic diversity, indicating that there is greater variability within population than between them, consistent with low genetic differentiation between population (GST = 0.046). Bayesian analysis identified three distinct groups; however, populations shared large numbers of alleles, which can be explained by the reduced distance between populations. These results reveal the need to implement genetic conservation programs for the maintenance of this species and to prioritize population from Bonito and Brasília, which showed the lowest values of genetic diversity.
Genet. Mol. Res. 15 (1).
DOI: 10.4238/gmr.15017785
Corresponding author: menezes.elytania@gmail.com
Genetic markers for detection of Escherichia coli K-12 harboring ampicillin-resistance plasmid from an industrial wastewater treatment effluent pond (2016)
Abstract:
Biotechnology industries that use recombinant DNA technology are potential sources for release of genetically modified organisms to the environment. Antibiotic-resistance marker genes are commonly used for recombinant bacteria selection. One example is the marker gene coding for β-lactamase (bla) in plasmids found in Escherichia coli K-12. The aim of this study was to provide an approach to develop a molecular method for genetic marker detection in E. coli K-12 harboring bla genes from an industrial wastewater treatment effluent pond (IWTEP). For the detection of bla and Achromobacter lyticus protease I (api) genes in samples from IWTEP, we employed multiplex polymerase chain reaction (PCR) using E. coli K-12 genetic marker detection primers, previously described in the literature, and primers designed in our laboratory. The microbiological screening method resulted in 22 bacterial colony-forming units isolated from three different IWTEP harvesting points. The multiplex PCR amplicons showed that five isolates were positive for the bla gene marker and negative for the E. coli K-12 and api genes. The 16S rRNA regions of positive microorganisms carrying the bla gene were genotyped by the MicroSeq®500 system. The bacteria found were Escherichia spp (3/5), Chromobacterium spp (1/5), and Aeromonas spp (1/5). None of the 22 isolated microorganisms presented the molecular pattern of E. coli K-12 harboring the bla gene. The presence of microorganisms positive for the bla gene and negative for E. coli K-12 harboring bla genes at IWTEP suggests that the ampicillin resistance found in the isolated bacteria could be from microorganisms other than the E. coli K-12 strain harboring plasmid.
Genet. Mol. Res. 15 (2).
DOI: 10.4238/gmr.15028528
Corresponding author: ericsson_aerc@yahoo.com.br
Spatial genetic structure of Cavanillesia arborea K. Schum. (Malvaceae) in seasonally dry Tropical forest: Implications for conservation (2015)
Abstract
Worldwide, Seasonally Dry Tropical Forests (SDTF) are among the least known and most degraded vegetation types. Cavanillesia arborea (Malvaceae) is an endemic dry forest tree that is bat-pollinated and the seeds are wind-dispersed. The present study sought to characterize the spatial genetic structure (SGS) in natural populations of C. arborea growing in SDTF fragments in Minas Gerais State, Brazil, using ISSR molecular markers. Seven ISSR primers generated 81 polymorphic loci in 175 individuals. In three populations (FU, MO and PC), we found random distributions of genotypes, while two populations (JAN and MV) showed SGS in their first distances classes (171 m and 17 m, respectively), with significant kinship (Sp) values (0.0189 and 0.0005 respectively; P < 0.05). Sp values for these populations indicate that the effects of kinship can be minimized by collecting seeds from distance classes beyond the species' first distance class. The continuous anthropogenic impacts on remnant tree populations, low species densities, and the observed genetic structure, all indicate the need to preserve large areas of dry forest vegetation for conservation purposes.
Biochemical Systematics and Ecology, v.58, p. 114–119. DOI:10.1016/j.bse.2014.11.004
Corresponding author: afraniofariasdemelo@gmail.com
Anatomy, Histochemistry, and Antifungal Activity of Anacardium humile (Anacardiaceae) Leaf (2015)
Abstract
Leaves of Anacardium humile are used in Brazilian traditional medicine for the treatment of intestinal disturbances and skin lesions. This study aimed to define leaf diagnostic structural characters, to propose a new method of phytochemical analysis of secretions, prospect flavonoids and alkaloids, and to evaluate their inhibitory activity on Candida albicans. Common anatomical, phytochemical, and microbiological methods were used. Leaves of Anacardium occidentale were used as a reference for the structural analyses. The main structural characters were closed vascular system, absence of ducts at the medulla, bilateral mesophyll, absence of bundle sheath extension, and secretory idioblasts at the xylem. The ducts present schizogenous origin, and secreting activity is restricted to the initial phases of leaf blade expansion. The proposed new phytochemical method is practical and inexpensive and has potential for wide application. The abundance of tannins and flavonoids is related to medicinal use. A single peak in high-performance liquid chromatography indicated the presence of a pure substance not previously reported. The extract had a strong inhibitory effect on C. albicans. The obtained results confirm the potential of A. humile for the prospection of new bioactive compounds.
Microscopy and Microanalysis, v. 21, n. 06, pp 1549-1561
DOI: 10.1017/S1431927615015457
Corresponding author: omercadante@hotmail.com
Antioxidant activity, total flavonoids and volatile constituents of Magonia Pubescens A.St.-Hil (2015)
Abstract
Magonia pubescens A.St.-Hil (Sapindaceae) (‘tingui’) is a typical medicinal plant of the Cerrado biome. This plant is used as a larvicide and employed in poison fishing. However, little is known of its secondary metabolites. In this study, it is described for the first time as the volatile constituents of M. pubescens, collected via headspace. Qualitative phytochemical analyses were performed. In addition, the antioxidant activity of the ethanol extracts of flowers and leaves were evaluated, and the total flavonoids were quantified. The ethanol extracts of flowers (12.67 ± 0.05 rutin equivalent (EQ) g-1) and leaves (11.81 ± 0.05 rutin EQ g-1). The leaf extracts exhibited higher IC50 values (18.14 ± 0.02 rutin EQ g-1) than did the flower extracts (31.19 ± 0.05 rutin EQ g-1). Twenty volatile compounds were identified in M. pubescens flowers through gas chromatography coupled with mass spectrometry (GC-MS), being identified as benzilic acid (17.9%) and styrene (13.9%) as the major compounds. The antioxidant activity of M. pubescens could be related to the presence of flavonoids and tannins, but further studies need to be conducted to fully understand that correlation. The identified volatiles have the potential to be used in the cosmetics industry due to their socio-economic relevance, and the may also contribute to the understanding of the reproductive success of this species.
Journal of Medicinal Plant Research. Vol.9(43), pp. 1089-1097.
DOI: 10.5897/JMPR2015.5983
Corresponding author: vanroyo31@gmail.com
Atividade Antinociceptiva e Antimicrobiana da Casca do Caule de Psidium Cattleyanum Sabine (2015)
Abstract
Psidium cattleyanum Sabine, conhecida como “araçá”, é espécie nativa do Bioma Cerrado brasileiro comumente utilizado, segundo levantamento etnobotânico, como planta medicinal para tratar várias doenças tais como: patologias hepáticas, gástricas, lesões teciduais incluindo processos dolorosos. O objetivo deste trabalho foi realizar a triagem fitoquímica com propósito exploratório, investigar a atividade analgésica e antimicrobiana do extrato hidroalcoólico da casca do caule de Psidium cattleyanum Sabine (ECPCS) para apoiar o uso dessa espécie como planta medicinal. Para isso, foram obtidos extratos e frações com solventes orgânicos de polaridade crescente (hexano, diclorometano, acetato de etila e isobutanol) avaliando-se o perfil fitoquímico para determinar as principais classes de metabólitos secundários presentes na espécie. Investigou-se a atividade analgésica pelo teste de contorções abdominais em camundongos induzidas pelo ácido acético (0,6%). A Concentração Inibitória Mínina (CIM) e Concentração Bactericida Mínima (CBM) foram avaliadas através da técnica de microdiluição em caldo contra micro-organismos da microbiota oral. A triagem fitoquímica identificou a presença de taninos, saponinas, flavonoides e terpenos e/ou esteroides. O ECPCS exibiu atividade analgésica periférica nas doses de 200 e 400 mg/kg. O EAC (extrato acetato de casca) o EDC (extrato diclorometânico de casca) desempenharam melhor ação inibitória sobre o crescimento bacteriano de Estafilococos oralis com CIM 100 e 150 respectivamente. O ECPCS desempenhou ação inibitória sobre o crescimento bacteriano. Os resultados dos estudos experimentais comprovaram a presença de compostos secundários tais como, taninos e flavonoides, o que, provavelmente, pode ser associado à atividade analgésica e ao efeito inibitório sobre os micro-organismos testados com o ECPCS, o que justifica o uso medicinal planta.
Rev. bras. plantas med. vol.17, n.4, pp.1125-1133.
DOI: 10.1590/1983-084X/14_146.
Corresponding author: menezes.elytania@gmail.com
Antibacterial activity of tannins from Psidium guineense Sw. (Myrtaceae). (2014)
Abstract
The aim of this study was to quantify and evaluate the antibacterial activity of tannins extracted from leaves of Psidium guineense, obtained using two different isolation methods, against Staphylococcus aureus and Pseudomonas aeruginosa. The first extraction method was used to isolate condensed tannins (Method A) and the second to isolate mixtures rich in esters of gallic acid and glucose (Method B). Both extraction methods yielded high concentrations of tannins, with 312 and 257 mg/g of dry material obtained using Methods A and B, respectively. These compounds formed halos of growth inhibition in S. aureus and P. aeruginosa cultures. Tannins isolated by method B gave rise to larger inhibition halos than those isolated by method A. Analysis of the antibacterial activity of tannins isolated by method B revealed a minimum inhibitory and bactericidal concentration of 256 μg/ml for S. aureus and 512 μg/ml for P. aeruginosa. These results demonstrate that P. guineense is a promising source of pharmacologically active tannin molecules, and further studies are therefore necessary to determine the toxicity of the plant and ensure its safe use for animal and human health.
Journal of Medicinal Plant Research, v. 8, p. 1095-1100
DOI: 10.5897/JMPR2014.5500
Corresponding author: peracio.bueno@gmail.com
Genetic diversity and structure of the tree Enterolobium contortisiliquum (Fabaceae) associated with remnants of a seasonally dry tropical forest. (2014)
Abstract
Fragmentation of tropical forests is one of the major threats to biodiversity and viable natural populations. Brazilian seasonally dry tropical forests (SDTF) are endangered because of human occupation, conversion of lands to agriculture and high deforestation rates in these fertile soils. Enterolobium contortisiliquum has been removed from SDTF natural areas due to the advance of cattle grazing and agriculture in Brazilian SDTFs. To aid conservation efforts of this species we used molecular markers to study the genetic diversity and population structure of E. contortisiliquum in Brazilian SDTF remnants. A total of 263 individuals in 13 forest patches were analyzed with 103 ISSR fragments. In spite of being found scattered among the SDTF patches, E. contortisiliquum populations exhibited high genetic diversity (mean Shannon's index of diversity = 0.384; mean genetic diversity = 0.280) and genetic divergence between populations was detected (ΦST = 0.155, p < 0.0001). UPGMA dendrogram, principal coordinate analysis and Bayesian analysis showed that E. contortisiliquum populations were clustered into three groups that were not related to geographic distance (r = 0.119, p = 0.197). However, these populations are spatially structured into groups distributed in the West, Central and East of the study area. This genetic structure may be related with landscape and both the Espinhaço Range and São Francisco River may act as a partial geographic barrier limiting the gene flow. Because the highest rates of genetic diversity were found outside of conservation units, we propose the creation of protected areas in different geographic regions that include E. contortisiliquum populations from different genetic clusters.
Flora (Jena), v. 50819, p. 1-7
DOI: 0.1016/j.flora.2014.10.005
Corresponding author: pattyabreu13@gmail.com
Structure, histochemistry and phytochemical profile of the bark of the sobol and aerial stem of Tontelea micrantha (Celastraceae - Hippocrateoideae). (2014)
Abstract
The bark of the underground stem of Tontelea micrantha (Mart. ex. Schult.) A. C. Sm., a native Brazilian Cerrado species, is used in folk medicine for treating kidney ailments. The structures of the underground and the aerial stems were examined and their barks were analyzed for the presence of secondary metabolites. Bark fragments were processed according to conventional techniques in plant anatomy and their chemical compositions examined using histochemical and phytochemical tests, thin layer chromatography, and high-efficiency liquid chromatography. The underground stem is a sobol with unusual cambial activity. Laticifers that secrete terpenoids were present in the cortex and phloem of both organs and can contribute to the identification of the species in field. Druses were present in both barks, but mono-crystals were only observed in the sobol. Tannins, flavonoids, alkaloids, and terpenoids occurred in both types of bark, but carotenoids were only detected in the sobol. The similarities between these two organs indicate that the aerial stem bark has potential medicinal use and represents a plausible alternative to harvesting the sobol, which could contribute to the preservation of natural populations of this species.
Anais da Academia Brasileira de Ciências, v. 86, p. 1167-1179
DOI: 10.1590/0001-3765201420130105
Corresponding author: omercadante@hotmail.com
Genetic diversity in populations of Acrocomia aculeata (Arecaceae) in the northern region of Minas Gerais, Brazil. (2012)
Abstract
Macaúba (Acrocomia aculeata) is a palm of economic importance, widely distributed in natural forests from Mexico to Uruguay. We analyzed the genetic diversity of populations of macaúba (A. aculeata) in the northern region of the State of Minas Gerais, Brazil. Young leaves from 10 macaúba individuals encompassing 49 genotypes of macaúba were collected from Montes Claros, Itacambira, Brasília de Minas, Mirabela, and Grão Mogol. After extraction and amplification of samples, the amplified fragments were separated by electrophoresis. We found high levels of genetic diversity within the populations. Genetic diversity indices were high, except in the Itacambira and Mirabela populations. Results show that Mirabela and Itacambira populations can require conservation strategies because they present lower values of genetic diversity.
Genetics and Molecular Research, v. 11, p. 531-538
DOI: 10.4238/2012.March.8.1
Corresponding author: dario.oliveira@unimontes.br