Abstract Alternaria alternata causes leaf spot and black rot diseases in leaves and grapes of grapevines, respectively, and leads to huge economic losses in table grapes production. As natural antifungal agents, essential oils (EOs), which are generally recognized as safe substances, shows strong antifungal activity against fungal phytopathogens. The aim of this study was to determine the chemical composition of Eucalyptus staigeriana EO and its in vitro and in vivo effects against A. alternata. The major compounds of E. staigeriana EO were citral (34.32%, of which 21.83% geranial and 12.49% neral), limonene (20.60%) and 1,8-cineole (12.33%). E. staigeriana EO exhibited the highest inhibitory activity on mycelial growth and conidial germination at 1 µL mL-1. Moreover, the EO was able to reduce the incidence and severity of leaf spot disease in leaves and black rot disease in table grapes caused by A. alternata. These results represent a possible alternative to reduce the use of synthetic molecules for the control of diseases in postharvest of table grapes and in vineyard.

OBJECTIVES: To determine the prevalence of class A extended spectrum β-lactamases (ESBL)-producing Escherichia coli and Klebsiella spp., and to investigate clonality among ESBL-producing isolates of nosocomial and community infections. METHODS: The study involved 354 nosocomial infections samples and 992 community infections samples, obtained between 2003 and 2006 at Caxias do Sul, RS. The detection of ESBL was performed by the disk-diffusion test. Presence of blaCTX-M, blaSHV and blaTEM β-lactamase genes was evaluated by PCR, and genomic typing was determined by pulsed-field gel electrophoresis analysis. RESULTS: Higher frequency of ESBL-producing isolates were detected among nosocomial samples of E. coli (6.7%) and Klebsiella (43.7%), than those obtained from community infections (0.4% and 2.6%). blaTEM and blaCTX were the most prevalent ESBL gene families in both E. coli and Klebsiella isolates. Different pulsotypes were obtained among ESBL-producing E. coli and 11 clones for Klebsiella spp., which occurred over the years and in different hospital wards. Among ESBL-producing K. pneumoniae, 74.3% transferred ESBL genes by conjugation and exhibited concomitant decreased aminoglycosides susceptibility. CONCLUSION: ESBL-producing E. coli, and especially K. pneumoniae are essentially a nosocomial problem, and their dissemination to the community is relatively limited. The great genetic variability observed among ESBL-producing bacteria indicates polyclonal spread and high transference of ESBL genes between bacteria in the hospital environment. This information is of paramount importance for nosocomial infection control.

This work is focused on the chemical distribution of volatile and semi-volatile compounds of 18 native populations of Maytenus ilicifolia collected all over Brazil. The extracts of bulk samples (30 plants) of each population were obtained by supercritical CO2 extraction technique, and analyzed by GC/MS. The quantification of compounds (phytol, squalene, vitamin E, limonene, stigmasterol, friedelan-3-ol, friedelin, fridelan-3-one, palmitic acid and geranyl acetate) showed significant variations within the different populations, which could be related tom microclimate characteristics.

A extração empregando dióxido de carbono a altas pressões em erva-mate (Ilex paraguariensis St. Hil.), tem sido justificada pelo crescente interesse desta matriz vegetal ou de parte de seus constituintes na formulação de novos produtos, tais como cosméticos e medicamentos, entre outros. Neste contexto, o objetivo do presente trabalho é avaliar a distribuição química de compostos semi-voláteis em 20 populações de erva-mate coletadas em toda área de distribuição desta espécie no Brasil. 30 plantas foram selecionadas para produzir a amostra de cada população. Os extratos de cada amostra foram obtidos por extração com dióxido de carbono a alta pressão e, posteriormente, foram analisados por CG/EM. A quantificação de alguns compostos semi-voláteis presentes nos extratos (cafeína, teobromina, fitol, esqualeno, vitamina E, eicosano, pentatriacontano e stigmasterol), apresentaram variações significativas entre as concentrações dos diferentes compostos analisados nas diferentes populações, os quais não estão relacionados com origem geográfica ou com características de macroclima. Os resultados apontam para a importância dos fatores genéticos e/ou fatores de microclima sobre a composição química desta espécie.

The use of compressed carbon towards extracting semi-volatile compounds present in maté leaves (Ilex paraguariensis St. Hil.) is due to the growing interest in mate constituents to develop new products in the cosmetic, pharmaceutical and food industries. The objective of this work was to assess the chemical distribution of semi-volatile compounds in 20 native populations of maté collected all over Brazil. The extracts of bulk samples (30 plants) of each population were obtained by the high-pressure carbon dioxide extraction technique, and analyzed by GC/MSD. The quantification of compounds (caffeine, theobromine, phytol, squalene, vitamin E, eicosane, pentatriacontane, and stigmasterol) showed significant variations within the different populations and compounds analyzed, which are not related to geographical origin or macroclimate characteristics. The results pointed out to the importance of genetic and local environmental factors on the chemical composition of this species.

As infecções nosocomiais constituem um importante problema em hospitais, sendo que as unidades de terapia intensiva (UTI) apresentam a maior incidência deste tipo de infecções. Os estafilococos, especialmente S. epidermidis e S. aureus, estão entre os microrganismos mais importantes associados às infecções nosocomiais. S. epidermidis é uma espécie colonizante da pele, sendo frequentemente inoculado durante procedimentos invasivos ou veiculado pela equipe de saúde, e essa situação é agravada pela emergência de cepas multirresistentes endêmicas no ambiente hospitalar. No presente trabalho foi avaliada a resistência a antibióticos e presença de distintos fatores de patogenicidade em 98 isolados clínicos de S. epidermidis obtidos de vários materiais em unidades de terapia intensiva e 20 colonizantes de pele de voluntários saudáveis. Os resultados obtidos mostraram elevada freqüência de isolados clínicos multirresistentes a antibióticos (76,5%), enquanto esta não foi detectada em isolados de voluntários saudáveis. A frequência de isolados multiresistentes foi 67,7% na UTI neonatal, 66,6% na UTI pediátrica, e 60,8% na UTI adulto, a menor freqüência de isolados multirresistentes na UTI adulto é indicativo de maior incidência de cepas comunitárias nesse local. As diferenças significativas na freqüência de isolados com atividades hemolítica, proteolítica e formação de biofilme, encontradas entre isolados clínicos e controles, indica a maior incidência de cepas com potencial patogênico no ambiente hospitalar. Não foi observada correlação entre multirresistência e fatores de patogenicidade, exceto uma baixa correlação positiva com a atividade hemolítica.

Nosocomial infections constitute an important problem in hospitals, intensive care units (ICU) having the highest incidence of this type of infection. Staphylococci, especially Staphylococcus epidermidis and Staphylococcus aureus, are among the most important microorganisms associated with nosocomial infections. S. epidermidis is a common skin resident, and can be introduced into the clinical environment by patients and hospital staff. The situation in hospitals is aggravated by the emergence of multiresistant strains. We evaluated 98 hospital S. epidermidis isolates collected at neonatal, pediatric and adult ICUs and 20 S. epidermidis control skin resident isolates from healthy volunteers, for resistance to ten antibiotics and chemotherapeutic agents, and other pathogenicity factors. A high frequency (76.5%) of multiresistance was detected in clinical isolates, whereas community isolates were resistant to penicillin and ampicillin only. The frequency of multiresistant strains was 67.7% in the neonatal ICU, 66.6% in the pediatric ICU and 60.8% in the adult ICU, the lower frequency of multiresistant isolates in the adult ICU indicates a higher incidence of community strains in this unit. There were significantly higher frequencies of hemolytic, proteolytic and biofilm-forming isolates in the clinical isolates than the community isolates, indicating a higher incidence of strains with pathogenic potential in the hospital environment. Except for slight correlation with hemolytic activity there was no correlation between antibiotic multiresistance and pathogenicity factors.

Proteínas de grão de 58 genótipos de arroz brasileiro e nove japoneses foram separadas por meio de eletroforese (SDS-PAGE). A observação densitométrica dos perfis eletroforéticos permitiu avaliar as concentrações relativas de 16 frações protéicas que foram usadas como variáveis para a estimativa de funções discriminantes de Fisher. Diferenças significantes foram encontradas entre as frações protéicas dos grupos brasileiros e japoneses, assim como entre os genótipos melhorados e não melhorados. O polimorfismo protéico detectável eletroforetica-mente nos grãos de arroz pode indicar a origem geográfica e o nível de melhoramento dos cultivares.

Grain proteins from 58 Brazilian and nine Japanese upland rice cultivars (Oryza sativa L.) were electrophoretically separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Densitometric scanning of the electrophoretic profiles permitted the estimation of the relative concentration of 16 protein fractions, which were used as variables for the calculation of Fisher's canonical discriminating functions. Significant differences between mean values of protein fractions were useful in distinguishing Brazilian and Japanese cultivars, as well as improved and non-improved Brazilian rice cultivars in scattered plots. Electrophoretically detectable protein polymorphism in rice grain can indicate geographic origin as well as breeding improvement level of a cultivar. Improved cultivars were those released by plant breeding institutes.