Activity of secondary bacterial metabolites in the control of citrus canker.

This study investigated the protective effects of secondary bacterial metabolites, produced by Pseudomonas sp. (bacterium strain LN), on citrus canker disease caused by Xanthomonas axonopodis pv. citri (Xac 306). The LN bacteria strain was cultured in liquid medium and the supernatant free-cells was treated with methanol (AMF) and ethyl acetate (AEF), respectively, and then the extract was concentrated, filtrated, lyophilized and fractionated by vacuum liquid chromatography (VLC). After VLC, eight fractions were obtained. All fractions? activity against Xac 306 by agar well diffusion assay and minimum inhibitory concentration but in different concentrations were tested. Cytotoxicity effects were observed in all fractions in 50 ?g?mL?1 concentration. The comet assay demonstrated that the fractions EAF, VLC2 and VLC3 presented no genotoxic effects at tested concentrations. In plants only VLC3 showed significant results (p < 0.05), reducing the incidence of citrus canker lesions

Secondary metabolites of Pseudomonas aeruginosa lv strain decrease asian soybean rust severity in experimentally infected plants.

Asian Soybean Rust (ASR), a disease caused by Phakopsora pachyrhizi, causing yield losses up to 90%. The control is based on the fungicides which may generate resistant fungi. The activation of the plant defense system, should help on ASR control. In this study, secondary metabolites of Pseudomonas aeruginosa LV strain were applied on spore germination and the expression of defense genes in infected soybean plants. The F4A fraction and the pure metabolites were used. In vitro, 10 µg mL−1 of F4A reduced spore germination by 54%, while 100 µg mL−1 completely inhibited. Overexpression of phenylalanine ammonia lyase (PAL), O-methyltransferase (OMT) and pathogenesis related protein-2 (PR-2; glucanases) defense-related genes were detected 24 and 72 h after soybean sprouts were sprayed with an organocopper antimicrobial compound (OAC). Under greenhouse conditions, the best control was observed in plants treated with 60 µg mL−1 of PCA, which reduced ASR severity and lesion frequency by 75% and 43%, respectively. Plants sprayed with 2 and 20 µg mL−1 of F4A also decreased severity (41%) and lesion frequency (32%). The significant reduction in spore germination ASR in plant suggested that the strain of these metabolites are effective against P. pachyrhizi, and they can be used for ASR control

The Effect of Phenazine-1-Carboxylic Acid on Mycelial Growth of Botrytis cinerea Produced by Pseudomonas aeruginosa LV Strain

One of the most important postharvest plant pathogens that affect strawberries, grapes and tomatoes is Botrytis cinerea, known as gray mold. The fungus remains in latent form until spore germination conditions are good, making infection control difficult, causing great losses in the whole production chain. This study aimed to purify and identify phenazine-1-carboxylic acid (PCA) produced by the Pseudomonas aeruginosa LV strain and to determine its antifungal activity against B. cinerea. The compounds produced were extracted with dichloromethane and passed through a chromatographic process. The purity level of PCA was determined by reversed-phase high-performance liquid chromatography semi-preparative. The structure of PCA was confirmed by nuclear magnetic resonance and electrospray ionization mass spectrometry. Antifungal activity was determined by the dry paper disk and minimum inhibitory concentration (MIC) methods and identified by scanning electron microscopy and confocal microscopy. The results showed that PCA inhibited mycelial growth, where MIC was 25 μg mL-1. Microscopic analysis revealed a reduction in exopolysaccharide (EPS) formation, showing distorted and damaged hyphae of B. cinerea. The results suggested that PCA has a high potential in the control of B. cinerea and inhibition of EPS (important virulence factor). This natural compound is a potential alternative to postharvest control of gray mold disease

Configuração e organização de imagens de serviços: um estudo exploratório Configuration and organization of the images of services: an exploratory study

O artigo aborda o desenvolvimento de uma pesquisa exploratória sobre a configuração de imagens no ambiente de serviços. Como ambiente de pesquisa, foi utilizado o Setor de Fisioterapia de um Plano de Saúde, no qual foi possível identificar três tipos de paciente com características específicas (pós-operatórios, neurológicos e crônicos). Com base na Teoria do Núcleo Central, foram identificadas as imagens dos serviços de fisioterapia para cada tipo de paciente, relacionando-as a determinados atributos. Tais atributos foram relacionados a um conjunto de elementos que constituem as imagens, o qual é composto por elementos funcionais, simbólicos, cognitivos e emocionais. Finalmente, no intuito de verificar e analisar o desempenho dos serviços prestados, sob a perspectiva de seus usuários, foi aplicada uma Escala de Diferencial Semântico e uma questão relativa ao grau de satisfação geral, o que pode consolidar ou redirecionar o processo de tomada de decisões.<br>The paper covers the development of an exploratory research about the image configuration in the service environment. To make this project, it was used the Sector of Physiotherapy of a Health Plan, in which it was possible to identify three kinds of patients with specific characteristics (pos-operator, neurological and chronic). With base on the Central Nucleus Theory, it was identified the images of the physiotherapy services for each kind of patient, relating them to determinate attribute. These attributes were related to some elements that make the images. These elements are: functional, symbolic, cognitive and emotional. Finally, with the objective to check and analyze the performance of the service done, under a perspective of the users, it was applied a Scale of Semantic Differential and a question about the overall satisfaction, what can help the manager in the process of making decisions