RESUMEN
Aspilia grazielae (J. U. Santos) is an endemic plant species in Morro do Urucum in the Pantanal wetland (Brazil). A. grazielae is used for the restoration of areas impacted by iron mining activities. This study evaluates the diversity (composition, value and abundance) of endophytic fungal communities, considering parts of the plant and soil condition. The leaves and roots of A. grazielae were collected from native vegetation areas (NVA) and recovery areas (RCA) in Morro do Urucum. Illumina sequencing technology was used to investigate variation in endophytic fungal biodiversity. The operational taxonomic units detected in NVA ranged from 183 to 263 (leaf) and 115 to 285 (root), while RCA samples ranged from 200 to 282 (leaf) and 156 to 348 (root). Ascomycota phylum was the most common species among all plant samples. The most significant classes identified were Lecanoromycetes and Dothideomycetes that differed significantly (p ≤ 0.05) according to their plant hosts and soil stress. The relative abundance of Pestalotiopsis (Sordariomycetes class) and Stereocaulon (Lecanoromycetes class) genera was influenced by the iron mining activities according to the leaf samples analysed. However, the abundance and wealth of endophytic fungal communities in A. grazielae from RCA were evidence that could explain their high resilience to environmental disturbances and the source-sink dynamics of fungal propagules.
RESUMEN
Aromatic amines (AA) are one of the most commonly used classes of compounds in industry and the most common pollutants found in both soil and water. 3,4-Dichloaniline (3,4-DCA) is a persistent residue of the phenylurea herbicide in the environment. In this study, we used a colorimetric method as a new approach to screen 12 filamentous fungal strains of the genera Aspergillus, Chaetomium, Cladosporium, and Mucor to assess their capacity to perform AA N-acetylation since it is considered a potential tool in environmental bioremediation. Subsequently, the selected strains were biotransformed with different AA substrates to evaluate the product yield. The strains Aspergillus niveus 43, Aspergillus terreus 31, and Cladosporium cladosporioides showed higher efficiencies in the biotransformation of 3,4-DCA at 500 µM into its N-acetylated product. These fungal strains also showed great potential to reduce the phytotoxicity of 3,4-DCA in experiments using Lactuca sativa seeds. Furthermore, N-acetylation was shown to be effective in reducing the cytotoxic and genotoxic effects of 3,4-DCA and other AA in the immortalized human keratinocyte (HaCaT) cell line. The isolated products after biotransformation showed that fungi of the genera Aspergillus and Cladosporium appeared to have N-acetylation as the first and main AA detoxification mechanism. Finally, A. terreus 31 showed the highest 3,4-DCA bioremediation potential, and future research can be carried out on the application of this strain to form microbial consortia with great potential for the elimination of toxic AA from the environment.
Asunto(s)
Herbicidas , Contaminantes del Suelo , Acetilación , Aminas/química , Compuestos de Anilina , Biodegradación Ambiental , Daño del ADN , Hongos/metabolismo , Herbicidas/metabolismo , Humanos , Suelo/química , Contaminantes del Suelo/metabolismo , Contaminantes del Suelo/toxicidad , AguaRESUMEN
Apparent calcium (Ca) retention and digestibility coefficients are affected by limestone particle size in the diet of laying hens. This study aimed to determine the apparent retention and digestibility coefficients of Ca in limestone of different particle sizes in laying hens. The study comprised 288 Lohmann Brown laying hens (50 weeks of age; 1,964 ± 98 g) distributed in a completely randomized experimental design with a 3 × 2 factorial arrangement [three Ca concentrations (10, 20, and 30 g kg-1) × two limestone particle sizes (480 and 1,978 µm)] with eight repetitions per treatment and six birds per experimental unit. The experiment included five days for adaptation and five days for total excreta collection. All birds were slaughtered at the end of the ten days to collect the ileal contents. The total or ileal Ca content was plotted against the Ca of diets concentration using linear regression analysis. The regression line slope represented the apparent retention (CaR) and digestibility coefficients of Ca (CaD) in limestone. There was interaction between Ca concentration in the diet and limestone granulometry on CaD (p = 0.001) and CaR (p < 0.001). The CaD and CaR of fine- and coarse-grained limestone increased linearly with increasing Ca concentrations in the diet. The apparent digestibility coefficients estimated for laying hens fed with fine-grained and coarse-grained limestone were 0.72 and 0.35, respectively. The apparent retention coefficients estimated for laying hens fed fine-grained and coarse-grained limestone were 0.96 and 0.47, respectively.
Asunto(s)
Animales , Aves/metabolismo , Carbonato de Calcio , Dieta , DigestiónRESUMEN
Erythrina fusca is a dominant species in the Brazilian Pantanal. We hypothesized that E. fusca possess allelopathic potential and we evaluated effects of extracts on germination and development of Lactuca sativa, a bioindicator species. We tested the effect of leaves, bark, roots, and seeds extracts of E. fusca on germination and speed index, using high, moderate and low concentration (0.2, 1 and 5 mg mL-1). To evaluate effects on development, we subjected seedlings of L. sativa to the same treatments and measured root and aerial part length. High concentration of extracts reduced L. sativa germination; leaves extract caused the maximum reduction on germination of L. sativa, similar to 2,4-Dichlorophenoxyacetic acid (2,4-D); this extract has flavonoids and saponins as main compounds, classes that also occur in the bark and roots extracts in lower concentrations; bark and roots (5 mg mL-1), leaves and roots (1 mg mL-1) decreased these traits as well, but in lower magnitude. A significant reduction in root length was induced by highest concentration of all extracts (5 mg mL-1); the results suggest that erythrinic alkaloids should interfere in the root length once the seeds accumulate almost exclusively this class of compounds. Our results showed that all parts of E. fusca had adverse effects on germination or development of L. sativa, showing that different class of compounds secondary metabolites is involved in this activity. Possibly, this phytotoxicity influences monodominance of E. fusca in Pantanal, but studies are essential to evaluate effects of it on other native species.
Asunto(s)
Alelopatía , Erythrina/química , Germinación/efectos de los fármacos , Lactuca/efectos de los fármacos , Extractos Vegetales/toxicidad , Brasil , Lactuca/crecimiento & desarrolloRESUMEN
Cardanol is a constituent of Cashew Nut Shell Liquid that presents larvicidal activity against Aedes aegypti. The isolation of cardanol is somewhat troublesome, however, in this work we describe an efficient and inexpensive method to obtain it as a pure material. The compound was used as starting material to make chemical transformation leading to saturated cardanol, epoxides and, halohydrins. These derivatives were tested for toxicity against Aedes aegypti larvae. The results showed that iodohydrins are very promising compounds for making commercial products to combat the vector mosquito larvae presenting a LC50 of 0.0023 ppm after 72 h of exposure.
Asunto(s)
Aedes/efectos de los fármacos , Insecticidas/farmacología , Fenoles/farmacología , Animales , Insecticidas/síntesis química , Insecticidas/toxicidad , Larva/efectos de los fármacos , Dosificación Letal Mediana , Fenoles/química , Fenoles/aislamiento & purificación , Fenoles/toxicidad , Factores de TiempoRESUMEN
ABSTRACT Cardanol is a constituent of Cashew Nut Shell Liquid that presents larvicidal activity against Aedes aegypti. The isolation of cardanol is somewhat troublesome, however, in this work we describe an efficient and inexpensive method to obtain it as a pure material. The compound was used as starting material to make chemical transformation leading to saturated cardanol, epoxides and, halohydrins. These derivatives were tested for toxicity against Aedes aegypti larvae. The results showed that iodohydrins are very promising compounds for making commercial products to combat the vector mosquito larvae presenting a LC50 of 0.0023 ppm after 72 h of exposure.
Asunto(s)
Animales , Fenoles/farmacología , Aedes/efectos de los fármacos , Insecticidas/farmacología , Fenoles/aislamiento & purificación , Fenoles/toxicidad , Fenoles/química , Factores de Tiempo , Insecticidas/síntesis química , Insecticidas/toxicidad , Larva/efectos de los fármacos , Dosificación Letal MedianaRESUMEN
A sustainable alternative to improve yield and the nutritive value of forage is the use of plant growth-promoting bacteria (PGPB) that release nutrients, synthesize plant hormones and protect against phytopathogens (among other mechanisms). Azospirillum genus is considered an important PGPB, due to the beneficial effects observed when inoculated in several plants. The aim of this study was to evaluate the diversity of new Azospirillum isolates and select bacteria according to the plant growth promotion ability in three forage species from the Brazilian Pantanal floodplain: Axonopus purpusii, Hymenachne amplexicaulis and Mesosetum chaseae. The identification of bacterial isolates was performed using specific primers for Azospirillum in PCR reactions and partial sequencing of the 16S rRNA and nifH genes. The isolates were evaluated in vitro considering biological nitrogen fixation (BNF) and indole-3-acetic acid (IAA) production. Based on the results of BNF and IAA, selected isolates and two reference strains were tested by inoculation. At 31 days after planting the plant height, shoot dry matter, shoot protein content and root volume were evaluated. All isolates were able to fix nitrogen and produce IAA, with values ranging from 25.86 to 51.26 mg N mL-1 and 107-1038 µmol L-1, respectively. The inoculation of H. amplexicaulis and A. purpusii increased root volume and shoot dry matter. There were positive effects of Azospirillum inoculation on Mesosetum chaseae regarding plant height, shoot dry matter and root volume. Isolates MAY1, MAY3 and MAY12 were considered promising for subsequent inoculation studies in field conditions.
Asunto(s)
Azospirillum/clasificación , Azospirillum/aislamiento & purificación , Poaceae/microbiología , Azospirillum/genética , Azospirillum/crecimiento & desarrollo , ADN de Hongos/análisis , Ácidos Indolacéticos/metabolismo , Fijación del Nitrógeno , Filogenia , Proteínas de Plantas/análisis , Raíces de Plantas/metabolismo , Raíces de Plantas/microbiología , Poaceae/crecimiento & desarrollo , Análisis de Secuencia de ADNRESUMEN
Herein, we report the synthesis of 12 new naphthoquinone derivatives, 6 substituted 1,4-naphthoquinones and 6 heterocycle-fused naphthoquinones, as well as evaluation of their trypanocidal and leishmanicidal activities. Compounds 11a and 13a were active against the amastigote stage of T. cruzi and showed low cytotoxic effects. With respect to leishmanicidal assays, all compounds were inactive against the promastigote stages of L. chagasi and L. braziliensis.
Asunto(s)
Antiprotozoarios/química , Leishmania/efectos de los fármacos , Naftoquinonas/química , Tripanocidas/química , Animales , Antiprotozoarios/farmacología , Línea Celular , Humanos , Espectroscopía de Resonancia Magnética , Naftoquinonas/farmacología , Espectrometría de Masa por Ionización de Electrospray , Tripanocidas/farmacologíaRESUMEN
The discovery and development of essential drugs for Chagas disease is a major concern worldwide. New substituted 1,4-naphthoquinones were synthesized and tested against the infective bloodstream form of Trypanosoma cruzi, the etiological agent of Chagas disease. These products exhibited substantial activity against T. cruzi, especially 2-((8E,11Z)-heptadeca-8,11-dienyl)-3-hydroxynaphthalene-1,4-dione (9) with IC(50) of 7.8 µM.
Asunto(s)
Antiprotozoarios/farmacología , Naftoquinonas/síntesis química , Naftoquinonas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Antiprotozoarios/síntesis química , Antiprotozoarios/química , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Estructura Molecular , Naftoquinonas/química , Pruebas de Sensibilidad ParasitariaRESUMEN
Cytotoxic activity of eight plant extracts, native from the Mid-West of Brazil comprising Cerrado, Pantanal and semideciduous forest, was evaluated for MDA-MB-435, SF-295, and HCT-8 cancer cell strains. A single 100 µg.mL-1 dose of each extract was employed with 72 h of incubation for all tests. Doxorubicin (1 µg.mL-1) was used as the positive control and the MTT method was used to detect the activity. Cytotoxicity of distinct polarities was observed in thirty extracts (46 percent), from different parts of the following species: Tabebuia heptaphylla (Vell.) Toledo, Bignoniaceae, Tapirira guianensis Aubl., Anacardiaceae, Myracrodruon urundeuva Allemão, Anacardiaceae, Schinus terebinthifolius Raddi, Anacardiaceae, Gomphrena elegans Mart., Amaranthaceae, Attalea phalerata Mart. ex Spreng., Arecaceae, Eugenia uniflora L., Myrtaceae, and Annona dioica A. St.-Hil., Annonaceae. Extracts of at least two tested cell strains were considered to be highly active since their inhibition rate was over 75 percent.
RESUMEN
The present study aimed to evaluate the ability for biotransformation of the Diels-Alder adduct tricyclo[6.2.1.0(2,7)]undeca-4,9-dien-3,6-dione (1) and two synthetic derivatives by the saprobe fungus Mucor ramosissimus Samutsevitsch. Products from oxidation, isomerization and, regioselective and enantioselective reduction were achieved.
Neste trabalho avaliou-se a capacidade de biotransformação do aduto de Diels-Alder triciclo[6.2.1.0(2-7)]undeca-4,9-dien-3,6-diona (1) e dois derivados sintéticos pelo fungo sapróbio Mucor ramosissimus Samutsevitsch. Produtos de oxidação, isomerização e redução regiosseletiva e enantiosseletiva foram obtidos.
RESUMEN
The present study aimed to evaluate the ability for biotransformation of the Diels-Alder adduct tricyclo[6.2.1.0(2,7)]undeca-4,9-dien-3,6-dione (1) and two synthetic derivatives by the saprobe fungus Mucor ramosissimus Samutsevitsch. Products from oxidation, isomerization and, regioselective and enantioselective reduction were achieved.
RESUMEN
This work deals with the preparation of stilbene-based resveratrol analogs by employing the Perkin reaction, aiming at synthesizing potential antitumor lead compounds and evaluating their pharmacological activities. The proliferation inhibitor test against tumor cell lines identified analogs 9 and 11 as the most active among all synthesized derivatives, presenting IC(50) in micromolar range for certain cell lines. For study on the embryonic development, compounds 8 and 9 at the lowest tested concentration (41.7 microM) that inhibited sea urchin egg development, but only after third cleavage were used. Both the compounds inhibited 100% of normal development since first cleavage. These data partially corroborated the results obtained with MTT assay using tumor cell lines. None of the tested compounds revealed hemolytic action in assay with mouse erythrocytes.
Asunto(s)
Antineoplásicos/síntesis química , Estilbenos/síntesis química , Animales , Antineoplásicos/farmacología , Antineoplásicos/toxicidad , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Desarrollo Embrionario/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Hemólisis/efectos de los fármacos , Humanos , Concentración 50 Inhibidora , Ratones , Óvulo , Resveratrol , Erizos de Mar , Estilbenos/farmacologíaRESUMEN
One of the ephemeral food sources that insects may use is the exudated gums from plants. In May 2005, in an area of Cerrado from Campo Grande, Mato Grosso do Sul, Brazil, insects visiting an exudation structure of an individual of Terminalia argentea Mart & Zucc (Combretaceae) were observed. Nineteen species were identified, mainly Trigona branneri (Cockerel) and Mesembrinella bicolor (Fabricius). All visitors had been observed collecting or ingesting the gum. Visitation time and behavior of the most abundant species were reported. Samples of exudates showed a low concentration of proteins and reducing sugars and high concentration of complex carbohydrate, allowing infer that visitors of T. argentea seek the gum a food resource of high molecular weight that contributes to the storage of energy reserves.
Uma das fontes efêmeras de alimento que os insetos podem utilizar são as gomas exsudadas por plantas. No mês de maio de 2005, em uma área de cerrado no município de Campo Grande, Mato Grosso do Sul, foram observados insetos visitando as estruturas de exsudação em um indivíduo de Terminalia agentea Mart & Zucc (Combretaceae). Foram registradas 19 espécies, principalmente Trigona branneri (Cockerell) e Mesembrinella bicolor (Fabricius). Todos os visitantes foram observados coletando ou ingerindo a goma exsudada. Observações sobre o horário de visitação e comportamento das espécies mais abundantes são relatadas. As amostras de exsudatos apresentaram baixa concentração de proteínas e açucares redutores e alta concentração de carboidratos complexos, permitindo inferir que os visitantes de T. argentea buscam na goma um recurso alimentar de alta massa molecular que contribui para o armazenamento de reservas energéticas.
Asunto(s)
Animales , Abejas , Combretaceae , Dípteros , Conducta Alimentaria , Pradera , PlantasRESUMEN
Esters of 2-hydroxy-4-methoxy-6-n-pentylbenzoic acid (2-8) (methyl, ethyl, butyl, pentyl, isopropyl, sec-butyl and benzyl), olivetol (9), methyl, ethyl, butyl perlatolates (10-12), 2,4-dihydroxy-6-n-pentylbenzoic acid (15), and methyl and ethyl esters of (15) were prepared through structural modifications of perlatolic acid (1) with the aim to detect new antifungal and antibacterial substances and also to evaluate the toxicity by the brine shrimp lethality assay against Artemia salina. The antifungal assays were carried out against the fungus Cladosporium sphaerospermum through the bioautography method, and methyl 2,4-dihydroxy-6-n-pentylbenzoate (13) showed the highest antifungal activity (2.5 yg). Olivetol (9) and 2,4-dihydroxy-6-n-pentylbenzoic acid (15) are also potent inhibitors of the growth of the fungus (5.0 microg). Except for methyl (10), the ethyl (11) and butyl (12) perlatolates were less active than perlatolic acid (1). The activities presented by methyl (2) and ethyl (3) 2-hydroxy-4-methoxy-6-n-pentylbenzoates and methyl (13) and ethyl (14) 2,4-dihydroxy-6-n-pentylbenzo-ates suggest that compounds with a free hydroxy group in the aromatic ring (C-4) have a more pronounced effect against C. sphaerospermum. Antibacterial activities were tested by the disc diffusion method using pathogenic strains of S. aureus and E. coli. The compounds were weakly active with inhibition zones between 9-15 mm. The 2-hydroxy-4-methoxy-6-n-pentylbenzoic esters 2-8 and alkyl perlatolates 10-12 were selective against E. coli. Perlatolic acid (1) and methyl 2-hydroxy-4-methoxy-6-n-pentylbenzoate (2) were the most active with LD50 values of 24.1 microM and 27.2 microM, respectively. The other compounds were not toxic to Artemia salina larvae.
Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Benzoatos/farmacología , Benzoatos/química , Cladosporium/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/efectos de los fármacosRESUMEN
Part of our research program concentrates on the discovery of new bioactive compounds prepared either by total synthesis or molecular transformation of compounds with bioactivity profiles. In this work we have focused our interest on chemical transformations of the Diels-Alder adduct tricyclo[6.2.1.0(2,7)]undeca-4,9-dien-3,6-dione in order to obtain cage-like compounds and derivatives, followed by an evaluation of their biological activity.
Asunto(s)
Proliferación Celular/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Hemólisis/efectos de los fármacos , Compuestos Policíclicos/síntesis química , Compuestos Policíclicos/farmacología , Animales , Humanos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Ratones , Conformación Molecular , Estructura Molecular , Compuestos Policíclicos/química , Estereoisomerismo , Células Tumorales CultivadasRESUMEN
In recent years, interest in the ability of non-pathogenic microorganisms to induce resistance in plants has grown, particularly with respect to their use as environmentally safe controllers of plant disease. In this study, we investigated the capacity of Mucor ramosissimus Samutsevitsch to release pectinases able to degrade cell walls of Palicourea marcgravii St. Hil., a tropical forest native Rubiaceae on which the spores of this saprobic fungus have been found. The fungus was grown in liquid culture medium containing pectin as the sole carbon source and filtrates were analyzed for pectinase activity. An endopolygalacturonase was partially purified by ion exchange chromatography, gel filtration, and preparative isoelectrofocusing, and characterized. This enzyme was more active upon pectic substrates with a low degree of methyl esterification. The products of hydrolysis of different pectic substrates (including pectin from P. marcgravii) by the action of this endopolygalacturonase elicited to different extents the phytoalexin production in soybean cotyledons. Also, the enzyme itself and the products of its action on the pectic fraction of P. marcgravii elicited the production of defensive compounds in the leaves of the plant. These results suggest that, besides the role in recycling organic matter, saprobes may also play an important role in the induction of defensive mechanisms in wild plants by enhancing their non-specific resistance against pathogens. Furthermore, they set the stage for future studies on the role of saprobic fungi in inducing resistance of host plants to pathogens.
Asunto(s)
Mucor/enzimología , Proteínas de Plantas/metabolismo , Poligalacturonasa/metabolismo , Rubiaceae/microbiología , Productos Biológicos/metabolismo , Productos Biológicos/farmacología , Pared Celular/metabolismo , Cladosporium/efectos de los fármacos , Cotiledón/efectos de los fármacos , Cotiledón/metabolismo , Medios de Cultivo , Esterificación , Hidrólisis , Mucor/crecimiento & desarrollo , Pectinas/metabolismo , Hojas de la Planta/metabolismo , Proteínas de Plantas/aislamiento & purificación , Poligalacturonasa/aislamiento & purificación , Sesquiterpenos , Glycine max/efectos de los fármacos , Glycine max/metabolismo , Especificidad por Sustrato , Terpenos/metabolismo , FitoalexinasRESUMEN
With the aim of obtaining new compounds with potential antifungal activity, lecanoric acid, a chemical constituent of the lichen Parmotrema tinctorum and its derivatives prepared from structural modification were tested against the fungus Cladosporium sphaerospermum, by employing the bioautographic method. Activity of the derivatives ranged from 10- to 1-ìg concentrations. Results demonstrated this series of compounds to have potent fungitoxic activity.
RESUMEN
Políssacaridases produzidas por fungos patogênicos desempenham um papel importante durante o processo de invasao das plantas hospedeiras. Vários estudos têm demonstrado que oligogalacturonídeos produzidos pela açao de endopoligalacturonases (EPGs) de fungos sobre a fraçao péctíca de paredes celulares de plantas, podem eliciar a síntese de fitoalexinas, além de estimular outros processos de defesa. No entanto, pouco é conhecido acerca da funçao das EPGs produzidas por fungos nao patogênicos, cujos esporos sao abundantes sobre a superfície das folhas, bem como do papel ecológico desempenhado por estes organismos na induçao de respostas de defesa em plantas. Os objetivos do presente trabalho foram (l) verificar a capacidade do fungo sapróbio Mucor ramosissimus em sintetizar pectinases, (2) investigar a açao desta enzimas sobre a fraçao péctica da parede celular de folhas de Palicourea marcgravii, uma rubiácea nativa de florestas tropicais, sobre cujas folhas foram detectados esporos de fungos sapróbios e (3) monitorar a capacidade dos produtos de hidrólise, oriundos da interaçao entre a enzima e o substrato péctico, de induzir a síntese de compostos de defesa em folhas de P. marcgravií e em cotilédones de soja. Observamos que o fungo é capaz de sintetizar pectinases somente quando cultivado em meios de cultura contendo pectina como fonte de carbono. As condiçoes ótimas de ensaio da enzima foram pH S,0 e 3OºC; a mesma foi capaz de reduzir em 50 por cento a viscosidade do substrato após lO min. de incubaçao, demonstrando que a hidrolase em estudo é uma endoenzima. A EPG de M. ramosissimus é uma glicoproteína com ponto jsoelétrico em torno de 9,0. Agiu sobre vários substratos pécticos com afinidade diferenciada sem aparente correlaçao com o grau de metílesterifíçao dos mesmos. Os produtos de hidrólise obtidos das incubaçoes da EPG de M. ramosissimus com esse substratos induziram, em diferentes intensidades, a síntese de fjtoalexinas em cotilédones de soja. Os hidrolisatos da fraçao péctica de P. marcgravii, bem como a própria enzima do fungo, foram potentes eliciadores da síntese de fjtoalexinas em cotilédones de soja e de compostos de defesa em folhas da espécie vegetal em estudo. Estes resultados sugerem que além do já conhecido papel desempenhado pelos fungos sapróbios na reciclagem da matéria orgânica, estes organismos podem ser importantes na induçao de mecanismos de defesa nao específicos em plantas...(au)