Biodegradation of the fungicide metalaxyl by zygomycetes

Publicado em "Biological resource centres : closing the gap between science and society : abstracts book...". ISBN 978-972-97916-5-9A large number of fungicides, such as metalaxyl [methyl N-(methoxyacetyl)-N-(2,6- xylyl)-DL-alaninate], are used against Oomycete species that cause downy mildew in agricultural crops, including grapes. However, these compounds are potentially harmful for terrestrial and aquatic environments, and to human health due to carcinogenic and mutagenic properties. There is an increase in interest in using filamentous fungi, such as members of the Zygomycetes which degrade xenobiotic compounds using nonspecific extracellular enzymes for the bioremediation of pesticides in polluted soils. In this study, several Zygomycetes including Gongronella, Absidia, Circinella and Rhizopus species, were used to screen degradation of metalaxyl using solid and liquid cultures. In order to identify and characterise these taxa a polyphasic approach including morphology characterization, molecular fingerprint M13-PCR and Matrix Assisted Laser Desorption Ionization Time of Flight Intact Cell Mass Spectrometry (MALDI-TOF ICMS) was used. After selective enrichment on solid medium containing a fungicide gradient concentration of 0-100 mg.L-1, Absidia glauca (CBS 101.08) and Rhizopus orizae (CCMI 900) showed a capacity to tolerate high metalaxyl concentrations. These resistant strains were selected to perform liquid assays using Yeast Nitrogen liquid cultures supplemented with sucrose (5 g.L-1) and metalaxyl (100 mg.L-1). Biomass concentration was determined by dry weight. The A. glauca and R. orizae strains showed specific growth rates of 0.774 h-1 and 0.999 h-1, respectively. Sucrose was completely consumed within 5 d with a sucrose consumption rate of 0.93 and 0.84 g.L-1.day-1 for A. glauca and R. orizae, respectively. The non-degraded metalaxyl in liquid cultures was determined by UVHPLC and evaluated periodically for 21 d. The metalaxyl degradation rate for A. glauca and R. orizae was 2.22 mg.L-1 .day-1 and 2.29 mg.L-1day-1, respectively. Results suggest that A. glauca (CBS 101.08) and R. orizae (CCMI 900) can be used in soil bioremediation experimentation for metalaxyl degradation. These strains are now under study to determine the presence of extracellular enzymes involved in the process

Efeito do gengibre no poder anaeróbico de membros inferiores de ginastas da seleção brasileira

Introduction: Aerobic gymnastics is a sport that has consistently grown over the previous decades, and its practice demands its athletes to perform complex and high-intensity movements. Objective: The study was to analyze whether ginger supplementation had an ergogenic effect on the anaerobic power of limbs (PAMI) in aerobic gymnastic athletes. Methods: A randomized double-blind placebo-controlled trial was conducted with nine athletes (23.11 + 4.14 years, 1.63 + 0.09 m, 60.51 + 7.38 kg) from the Brazilian National Team of Aerobic Gymnastics. After ingesting 400 mg of Zingiber officinale or placebo for seven days, the subjects underwent an anaerobic power test (RAST). Peak Velocity and Peak power (m/s and W), average and minimum power (W), and fatigue index (W/s and %) data were obtained from the RAST. Results: After verifying the no normality of the sample, the Mann-Whitney was applied, but no significant differences were found in the peak velocity of the ginger supplementation (6.28 ± 0.41 m/s; 445.28 ± 117.15 W) compared to placebo (6.22 ± 0.45 m/s; 425.95 ± 130.39 W). Conclusions: It is concluded that ingesting 400 mg of Z. officinale does not have an ergogenic effect on the anaerobic power of the lower limbs of aerobic gymnastic athletes.Introdução: a ginástica aeróbica é um esporte que tem crescido consistentemente nas últimas décadas, e sua prática exige que seus atletas realizem movimentos complexos e de alta intensidade. Objetivo: analisar se a suplementação com gengibre tem efeito ergogênico no poder anaeróbico dos membros (PAMI) em atletas de ginástica aeróbica. Métodos: foi realizado um estudo randomizado, duplo-cego, controlado por placebo, com nove atletas (23,11 + 4,14 anos, 1,63 + 0,09 m, 60,51 + 7,38 kg) da Seleção Brasileira de Ginástica Aeróbica. Após a ingestão de 400 mg de Zingiber officinale ou placebo por sete dias, os indivíduos foram submetidos a um teste de potência anaeróbica (RAST). Os dados de Velocidade de pico e Potência de pico (m/s e W), potência média e mínima (W) e índice de fadiga (W/s e %) foram obtidos no RAST. Resultados: Após verificar a não normalidade da amostra, foi aplicado o Mann-Whitney, mas não foram encontradas diferenças significativas na velocidade de pico da suplementação de gengibre (6,28 ± 0,41 m / s; 445,28 ± 117,15 W) em comparação ao placebo (6,22 ± 0,45 m / s; 425,95 ± 130,39 W). Conclusões: conclui-se que a ingestão de 400 mg de Z. officinale não exerce efeito ergogênico no poder anaeróbico dos membros inferiores de atletas de ginástica aeróbica

Simulation of aboveground biomass production under different rainfall scenarios and soil types in the Caatinga Biome, Brazil

Drought years have a negative impact on the livestock production systems of the Brazilian semiarid region because of the strong reduction of forage production on the rangelands. Although drought is recurrent in the Brazilian semiarid, up to the present moment, there are notools that could help farmers to mitigate the effects of these extreme climate conditions. In this sense, simulation of biochemical cycles using mathematical models could be a helpful tool to understand these processes. The Century model has been largely used to estimate the impact of different environmental variables, management practices, and climate scenarios in the vegetation. The study aims to evaluate the Century model to simulate the dynamics of aboveground biomass production and soil carbon in the Caatinga ecosystem under three different rainfall scenarios: 1) Precipitation 50% below the long-term average; 2) Long-term average rainfall; 3) 50% above the long-term average rainfall. Moreover, two types of soil (sandy and clay) were evaluated in the simulations. Dry years led to 42 and 20% reductions in aboveground biomass production in the shrubby and herbaceous layers, respectively, but there were no significant differences between soil types. Further adjustments in the model are required to simulate herbaceous biomass in the Caatinga ecosystem. At the end of the adaptation phase, we expect that the Century model will generate useful information to fill the lack of knowledge about variability of forage production in the Caatinga, helping in the adaptation to possible climate changes

Routine screening of harmful microorganisms in beach sands: implications to public health

Beaches worldwide provide recreational opportunities to hundreds of millions of people and serve as important components of coastal economies. Beach water is often monitored for microbiological quality to detect the presence of indicators of human sewage contamination so as to prevent public health outbreaks associated with water contact. However, growing evidence suggests that beach sand can harbor microbes harmful to human health, often in concentrations greater than the beach water. Currently, there are no standards for monitoring, sampling, analyzing, or managing beach sand quality. In addition to indicator microbes, growing evidence has identified pathogenic bacteria, viruses, and fungi in a variety of beach sands worldwide. The public health threat associated with these populations through direct and indirect contact is unknown because so little research has been conducted relating to health outcomes associated with sand quality. In this manuscript, we present the consensus findings of a workshop of experts convened in Lisbon, Portugal to discuss the current state of knowledge on beach sand microbiological quality and to develop suggestions for standardizing the evaluation of sand at coastal beaches. The expert group at the "Microareias 2012" workshop recommends that 1) beach sand should be screened for a variety of pathogens harmful to human health, and sand monitoring should then be initiated alongside regular water monitoring; 2) sampling and analysis protocols should be standardized to allow proper comparisons among beach locations; and 3) further studies are needed to estimate human health risk with exposure to contaminated beach sand. Much of the manuscript is focused on research specific to Portugal, but similar results have been found elsewhere, and the findings have worldwide implications

Routine screening of harmful microorganisms in beach sands: implications to public health

Beaches worldwide provide recreational opportunities to hundreds of millions of people and serve as important components of coastal economies. Beach water is often monitored for microbiological quality to detect the presence of indicators of human sewage contamination so as to prevent public health outbreaks associated with water contact. However, growing evidence suggests that beach sand can harbor microbes harmful to human health, often in concentrations greater than the beach water. Currently, there are no standards for monitoring, sampling, analyzing, or managing beach sand quality. In addition to indicator microbes, growing evidence has identified pathogenic bacteria, viruses, and fungi in a variety of beach sands worldwide. The public health threat associated with these populations through direct and indirect contact is unknown because so little research has been conducted relating to health outcomes associated with sand quality. In this manuscript, we present the consensus findings of a workshop of experts convened in Lisbon, Portugal to discuss the current state of knowledge on beach sand microbiological quality and to develop suggestions for standardizing the evaluation of sand at coastal beaches. The expert group at the "Microareias 2012" workshop recommends that 1) beach sand should be screened for a variety of pathogens harmful to human health, and sand monitoring should then be initiated alongside regular water monitoring; 2) sampling and analysis protocols should be standardized to allow proper comparisons among beach locations; and 3) further studies are needed to estimate human health risk with exposure to contaminated beach sand. Much of the manuscript is focused on research specific to Portugal, but similar results have been found elsewhere, and the findings have worldwide implications