Isolamento e atividade antibacteriana de fungos endofíticos de Piper glabratum Kunth / Isolation and antibacterial activity of Piper glabratum Kunth endophytic fungi

Devido a capacidade dos endófitos em colonizar diferentes espécies de plantas, inclusive as medicinais, produzindo substâncias de interesse biotecnológico como antibióticos, o objetivo deste trabalho foi isolar fungos endofíticos de folhas de Piper glabratum Kunth e avaliar a atividade antibacteriana contra bactérias patogênicas humanas. O isolamento dos fungos endofíticos foi realizado utilizando-se a desinfestação superficial com hipoclorito de sódio 3%. Para avaliação da atividade antibacteriana, foi obtido extrato de 20 fungos endofíticos isolados que foram testados o extrato diretamente na fase aquosa, a fração obtida com acetato de etila e com clorofórmio P.A. Foi utilizado o teste de difusão em discos contra as bactérias patogênicas humanas Escherichia coli, Staphylococcus aureus, Salmonella enterica e Shigella flexneri. Em placas de Petri com meio Muller Hinton (MH) contendo as bactérias foram inseridos quatro discos de papel estéreis inoculados com 10 µL de cada extrato metabólito. Avaliou-se a atividade antimicrobiana pela formação de halos de inibição. Foi possível isolar 98 de P. glabratum, com frequência de isolamento de 98%. Dentre os 20 fungos avaliados quanto a atividade antimicrobiana, catorze isolados apresentaram atividade antibacteriana para pelo menos uma das quatro bactérias patogênicas testadas, destacando-se potencial de inibição para a bactéria S. aureus a partir dos testes realizados diretamente com o extrato bruto e com acetato de etila.

Endophytes are able to colonize different species of plants, including medicinal plants, producing substances of biotechnological interest such as antibiotics. Therefore, the aim of this study was to isolate endophytic fungi from Piper glabratum Kunth leaves and evaluate the antibacterial activity against human pathogenic bacteria. The isolation of endophytic fungi was performed using the surface disinfection method with 3% sodium hypochlorite. In order to evaluate the antibacterial activity, extracts from 20 endophytic fungi were tested, with the extract directly into the aqueous phase and the fraction obtained with ethyl acetate and chloroform P.A. The method of disk diffusion was used against human pathogenic bacteria Escherichia coli, Staphylococcus aureus, Shigella flexneri and Salmonella enterica. In Petri dishes with medium Muller Hinton (MH) containing bacteria, four sterile paper disks inoculated with 10 µL of each metabolite extract were inserted. The antimicrobial activity was evaluated due to the formation of the inhibition halo. It was possible to isolated 98 endophytic fungi from P. glabratum with isolation frequency of 98%. The results of the test showed that extracts from 20 endophytic fungi have inhibited the activity against fourteen isolates and antibacterial activity for at least one of the four tested pathogenic bacteria, emphasizing the potential for inhibition of S. aureus from the tests performed directly with the crude extract and ethyl acetate.

La previsión episódica en la etapa pre-escolar: equivalencia entre medidas y su relación con los procesos de orientación futura y la teoría de la mente / Episodic foresight in preschool age: equivalence between measures and the relation with future oriented processes and the theory of mind

Este trabajo examina la equivalencia entre diferentes medidas de previsión episódica y su relación con los procesos orientados a futuro, y la teoría de la mente en la edad pre-escolar. Los procesos orientados a futuro y la previsión episódica (PE), han sido señalados como componentes importantes para ciertos logros evolutivos como la planificación, la auto-regulación y adaptación social. También se ha postulado que pensamiento futuro episódico y teoría de la mente están relacionados, en virtud de su sustrato neural compartido. El primer estudio tuvo por objetivo analizar la coherencia de desarrollo entre las medidas de PE, y de estas con la postergación de la gratificación auto-impuesta controlando según la aptitud general de razonamiento, y participaron 15 niños de 3 y 4 años. El segundo, tuvo por objetivo explorar la relación entre PE, los procesos orientados a futuro, la teoría de la mente controlando según lenguaje, participando 78 niños de 4 años. Los resultados muestran que las diferentes medidas para evaluar la PE son equivalentes. También se encontró un alto grado de coherencia comportamental entre las medidas evaluadas. Sin embargo, los datos no aportan evidencia evolutiva que permitan incluir a la PE dentro de los constructos más amplios estudiados.

This paper explores the equivalence between episodic foresight measures and its relationship with future oriented processes and the theory of mind in preschoolers. Future oriented processes and episodic foresight have been indicated as a grounding basis of important developmental achievements such as planning, self-regulation and social adaptation. Also, it was postulated that the theory of mind and episodic foresight are related due to a shared common neural substrate. The objective of the first study, in which 15 children aged 3 and 4 participated, was to explore the developmental coherence between episodic foresight measures and the self-imposed delay of gratification controlled by the reasoning ability. In Study 2, 78 children were tested in episodic foresight, future oriented processes and theory of mind controlled by the language ability. Results show that the different measures of episodic foresight are highly equivalent. Also, in both studies a high behavioral coherence between all the measures analyzed was found. Nevertheless, data do not support the inclusion of episodic foresight in the broader constructs studied.

Prospecção fitoquímica e avaliação da citotoxicidade e genotoxicidade de Helenium cf. amarum (Raf.) H. Rock / Phytochemical screening and evaluation of the cytotoxicity and genotoxicity of Helenium cf. amarum (Raf.) H. Rock / Tamizaje fitoquímico y evaluación de la citotoxicidad y genotoxicidad del Helenium cf. amarum (Raf.) H. Rock

Introduction: Helenium cf. amarum (Raf.) H. Rock is a plant of the family Asteraceae. Its common name is yellow camomile. It is used as tranquilizer, stimulant and digestive, and for the treatment of nausea, fever and skin disorders. Objectives: carry out a phytochemical screening and evaluate the cytotoxic and genotoxic effect of a crude hydroalcoholic extract of Helenium amarum using the Allium cepa test. Methods: seeds of Allium cepa were subjected to germination at four concentrations (0.6, 1.0, 2.0 and 3.0 mg/ml) of H. amarum crude leaf extract. After being dried in an oven for 5 days, they were pulverized and macerated in 70 % ethanol at room temperature for 72 hours. The extract was then filtered and the liquid phase subjected to a rotary evaporator. Two sorts of treatment were applied: 1) continuous treatment: the seeds were germinated directly in the extract at different concentrations. 2) intermittent treatment: the seeds were first germinated in Milli-Q water until they grew 2 cm long rootlets, and were then exposed to different extract concentrations. Results: the germination rate was affected by extract concentration, and was lower than that of the negative control in all treatments. The mitotic index for all concentrations was lower than that of controls for both treatments. In batch processing, the aneugenic effects index at the assayed concentrations was lower than that of controls, whereas the clastogenic index was 1 % for the control and treatments 1 and 3 mg/ml, lower than 1 % for treatments 0.6 and 2 mg/ml, and 20 % for the positive control. Phytochemical screening showed positive results for tannins and steroids. Conclusions: Helenium amarum has toxic and cytotoxic effects and allelopathic action, but not genotoxic effects at the assayed concentrations.

Alcoholic fermentation by the wild yeasts under thermal, osmotic and ethanol stress

This study aimed to explore the variability in the metabolism of nine wild yeasts isolated from the sugarcane juice from a distillery in the Brazilian State of Mato Grosso. Cell viability under the stress conditions was evaluated. The yeasts were inoculated in the test tubes containing sugarcane juice adjusted from 12 to 21º Brix, ethanol from 6 to 12% in volume and temperature at 30, 35 and 40ºC. The viability was established by the growth in Petri dishes and visually by the CO2 production in the test tubes. None of the evaluated yeasts showed simultaneous resistance to the three stress conditions. The potential of yeast BB.09 could be emphasized due to its ability to ferment up to12% ethanol at 30°C.

Prospecção fitoquímica do arilo de sementes de maracujá amarelo e influência em germinação de sementes / Phytochemical screening of the arils of yellow passion fruits seeds and influence on the seed germination

O maracujazeiro amarelo é propagado por sementes que apresentam problemas na sua germinação devido à presença do arilo que pode conter substâncias inibidoras. O trabalho foi realizado com o objetivo de identificar as classes de metabolitos especiais contidas no arilo das sementes de maracujá amarelo. Para isso, após a extração do arilo das sementes de maracujá amarelo, foram obtidos os extratos de diclorometano e metanol. As classes foram identificadas por meio de prospecção fitoquímica aliada à análise de espectros de infravermelho e ressonância magnética nuclear de hidrogênio (RMN 1H) de frações dos extratos obtidas com fracionamento em coluna de gel de sílica. Para avaliação da sensibilidade das sementes a essas substâncias, foram instalados testes de germinação com sementes de alface. No extrato de arilo obtido com diclorometano, identificaram-se esteróides e triterpenóides, verificou-se inibição da germinação das sementes. No extrato metanólico, identificaram-se açúcares redutores e verificou-se redução da germinação das sementes.

The passion fruit is propagated by seeds that have problems in their germination due to the presence of aryl which may contain inhibitory substances. The aim of this research was to identify the metabolites classes contained on the aril of yellow passion fruit. For this, after arils extraction, dichlorometane and methanol extracts were obtained. The Classes of metabolites were identified by phytochemical screening coupled with infrared spectroscopy and nuclear magnetic resonance (1H NMR) and extract fractions were obtained by fractionation on a column of silica gel. To evaluate the sensitivity of seeds to these substances, germination tests with lettuce seeds were installed. In aril extract obtained with dichloromethane, steroids and triterpenoids were identified and inhibition of seeds germination observed. In the methanol extract, reducing sugars were found and it was verified reduction of seeds germination.

Associação de bioensaios e caracterização molecular para seleção de novos isolados de Bacillus thuringiensis efetivos contra Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) / Association of bioassays and molecular characterization to select new Bacillus thuringiensis isolates effective against Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae)

A lagarta de Spodoptera frugiperda (J. E. Smith) é uma das principais pragas do milho e para seu controle o Bacillus thuringiensis se destaca por sua atividade entomopatogênica. Este trabalho objetivou a caracterização molecular de isolados de B. thuringiensis quanto à presença do gene cry1 e a avaliação da sua eficiência no controle de lagartas de S. frugiperda. Nas análises da PCR, foi utilizado o Gral-cry1 para confirmação da presença do gene cry1 nos 115 isolados. Uma suspensão de 3 x 10(8) esporos/ml banhou a dieta utilizada para alimentação de 30 lagartas por isolado, com três repetições. A identificação do tipo de genes cry1 dos diferentes isolados foi realizada para cinco sub-classes de genes e análises de regressão linear foram realizadas para verificar possíveis associações entre a presença de um gene cry individual e altos níveis de toxicidade. Ttodos os DNAs amplificados com os iniciadores Gral-cry1 apresentaram produto de amplificação com tamanho esperado. Quanto aos níveis de eficiência inseticida contra a lagarta-do-cartucho, 41 isolados apresentaram 100 por cento de mortalidade e 16 apresentaram índice entre 75 por cento e 90 por cento. O gene cry1Ab esteve presente em 80 isolados, cryB em 69 isolados, cry1Ac em todos os isolados, cryV e cry1E em 93 e 27 isolados, respectivamente. Os valores referentes ao efeito individual de cada gene na mortalidade de larvas foram significativos a 1 por cento de probabilidade, para os genes cry1Ac e cry1E.

The fall armyworm, Spodoptera frugiperda (J. E. Smith), is one of the main corn pests and Bacillus thuringiensis is important in its control because of its entomopathogenic property. The objective of this study was the molecular characterization of B. thuringiensis isolates for cry1 locus presence and the assessment of the efficiency of these isolates in controlling S. frugiperda caterpillars. Gral-cry1 was used in the PCR analyses to confirm the presence of the cry1 locus in 15 isolates. A 3 x 10(8) spore/ml suspension bathed the diet used to feed 30 caterpillars per isolate, with three replications. The cry1 locus type genes of the different isolates were identified for five gene subclasses; linear regression analyses were carried out to ascertain possible associations between the presence of an individual cry1 locus gene and high levels of toxicity. All the DNAs amplified with Gral-cry1 presented an amplification product with the expected size. Regarding the levels of insecticide efficiency against the cob worm, 41 isolates presented 100 percent mortality and 16 presented an index between 70 percent and 90 percent. The cry1Ab gene was present in 80 isolates, cryb in 69 isolates, cry1Ac in all the isolates and cryv and cry1E in 93 and 27 isolates, respectively. The values regarding the individual effect of each gene on caterpillar mortality were significant at 1 percent probability for the cry1Ac and cry1E genes.

Caracterização farmacognóstica de folhas de Davilla elliptica St.-Hil. (Dilleniaceae) / Pharmacognostic characterization of the leaves of Davilla elliptica St.-Hil. (Dilleniaceae)

Davilla elliptica St.-Hil. é empregada popularmente no tratamento de hemorróidas, diarréias e ferimentos. O propósito deste trabalho foi realizar o estudo farmacognóstico de folhas de D. elliptica de dois locais do Estado de Goiás. Cortes paradérmicos e transversais foram submetidos a técnicas usuais de microscopia óptica. As folhas de D. elliptica são hipoestomáticas, sendo os estômatos predominantemente paracíticos. Na epiderme observam-se tricomas unicelulares em ambas faces. O mesofilo é isobilateral e apresenta idioblastos cristalíferos. O sistema vascular na nervura principal é constituído por três feixes vasculares, formando uma estrutura circular. No pecíolo o sistema vascular apresenta uma estrutura circular formada, provavelmente, pela união de vários feixes vasculares. O material pulverizado foi submetido a testes de prospecção fitoquímica, de pureza e quantitativo. Foi constatada a presença de taninos, cumarinas, resinas, flavonóides, saponinas, esteróides e triterpenóides. Os teores de cinzas totais foram de 10,32 por cento e 12,26 por cento; os de cinzas insolúveis em ácido, 7,46 por cento e 9,68 por cento; e os de umidade, 9,92 por cento e 9,50 por cento. Os teores de flavonóides totais foram de 1,20 por cento e 1,48 por cento, e os de taninos 9,89 por cento e 13,96 por cento. Devido ao número reduzido de amostras, não é possível afirmar, através deste estudo, que o perfil farmacognóstico de D. elliptica seja influenciado por fatores abióticos.

Davilla elliptica St.-Hil. is popularly used in the treatment of hemorrhoid, diarrhea and wounds. The aim of this work was to characterize pharmacognosticaly two leaves samples of D. elliptica. Paradermal and transversal sections had been submitted the usual techniques of optical microscopy. The leaves of D. elliptica are hypostomatics, and the stomata predominantly paracytic. In both epidermis were observed unicellular non-glandular trichomes. The mesophyll is isolateral and shows idioblasts with crystals in raphide. The vascular system in the midrib is constituted by three vascular bundles, forming a circular structure. The petiole shows a circular structure probably formed by union of many vascular bundles localized in the central region. The powdered plant material was submitted to tests of phytochemical prospection, of purity and quantitative. There had been evidenced the presence of tannins, coumarins, resins, flavonoids, saponins and steroids. The content of total ashes was of 10,32 percent and 12,26 percent, insoluble in acid of 7,46 percent and 9,68 percent; the humidity of 9,92 percent and 9,50 percent. The flavonoids contents was of 1,20 percent and 1,48 percent; the tannins contents was of 9,89 percent and 13,96 percent. Because of the reduced number of samples, it was not possible to affirm through this study that the pharmacognostic profile de D. elliptica is influenced by abiotics factors.