Heavy metals influence the population size, diversity, and metabolic activity of bacteria. In turn, bacteria can develop heavy metal resistance mechanisms, and this can be used in bioremediation of contaminated areas. The purpose of the present study was to understand how heavy metals concentration influence on diversity and distribution of heavy metal-resistant bacteria in Araça Bay, São Sebastião, on the São Paulo coast of Brazil. The hypothesis is that activities that contribute for heavy metal disposal and the increase of metals concentrations in environment can influence in density, diversity, and distribution of heavy metal-resistant bacteria. Only 12 % of the isolated bacteria were sensitive to all of the metals tested. We observed that the highest percentage of resistant strains were in areas closest to the São Sebastião channel, where port activity occurs and have bigger heavy metals concentrations. Bacterial isolated were most resistant to Cr, followed by Zn, Cd, and Cu. Few strains resisted to Cd levels greater than 200 mg L(-1). In respect to Cr, 36 % of the strains were able to grow in the presence of as much as 3200 mg L(-1). Few strains were able to grow at concentrations of Zn and Cu as high as 1600 mg L(-1), and none grew at the highest concentration of 3200 mg L(-1). Bacillus sp. was most frequently isolated and may be the dominant genus in heavy metal-polluted areas. Staphylococcus sp., Planococcus maritimus, and Vibrio aginolyticus were also isolated, suggesting their potential in bioremediation of contaminated sites.
Bacterial resistance is a rising problem all over the world. Many studies have showed that beach sands can contain higher concentration of microorganisms and represent a risk to public health. This paper aims to evaluate the densities and resistance to antimicrobials of Escherichia coli strains, isolated from seawater and samples. The hypothesis is that microorganisms show higher densities in contaminated beach sands and more antimicrobial resistance than the water column. Density, distribution, and antimicrobial resistance of bacteria E. coli were evaluate in seawater and sands from two recreational beaches with different levels of pollution. At the beach with higher degree of pollution (Gonzaguinha), water samples presented the highest densities of E. coli; however, higher frequency of resistant strains was observe in wet sand (71.9 %). Resistance to a larger number of antimicrobial groups was observe in water (betalactamics, aminoglycosides, macrolides, rifampicins, and tetracyclines) and sand (betagalactamics and aminoglycosids). In water samples, highest frequencies of resistance were obtain against ampicilin (22.5 %), streptomycin (15.0 %), and rifampicin (15.0 %), while in sand, the highest frequencies were observe in relation to ampicilin (36.25 %) and streptomycin (23.52 %). At the less polluted beach, Ilha Porchat, highest densities of E. coli and higher frequency of resistance were obtain in wet and dry sand (53.7 and 53.8 %, respectively) compared to water (50 %). Antimicrobial resistance in strains isolated from water and sand only occurred against betalactamics (ampicilin and amoxicilin plus clavulanic acid). The frequency and variability of bacterial resistance to antimicrobials in marine recreational waters and sands were related to the degree of fecal contamination in this environment. These results show that water and sands from beaches with a high index of fecal contamination of human origin may be potential sources of contamination by pathogens and contribute to the dissemination of bacterial resistance.
This article is made publicly available in the institutional repository of Wageningen University and Research, under the terms of article 25fa of the Dutch Copyright Act, also known as the Amendment Taverne. This has been done with explicit consent by the author.Article 25fa states that the author of a short scientific work funded either wholly or partially by Dutch public funds is entitled to make that work publicly available for no consideration following a reasonable period of time after the work was first published, provided that clear reference is made to the source of the first publication of the work.This publication is distributed under The Association of Universities in the Netherlands (VSNU) 'Article 25fa implementation' project. In this project research outputs of researchers employed by Dutch Universities that comply with the legal requirements of Article 25fa of the Dutch Copyright Act are distributed online and free of cost or other barriers in institutional repositories. Research outputs are distributed six months after their first online publication in the original published version and with proper attribution to the source of the original publication.
RESUMOO Brasil apresenta diversidade representativa de aves marinhas residentes e migratórias. Muitas dessas aves são encontradas debilitadas nas praias e são levadas para centros de reabilitação para tratamento e posterior soltura. Algumas dessas aves marinhas, devido ao aumento da poluição costeira e próprio estresse do manejo e do cativeiro, podem ser acometidas por doenças bacterianas e fungicas. Dessa maneira, o presente trabalho tem como objetivo caracterizar as principais espécies de fungos e bactérias presentes no trato respiratório de aves marinhas encontradas debilitadas na região costeira da Baixada Santista. Através das analises microbiológicas foram encontrados seis gêneros principais de bactérias: Staphylococcus sp, Streptococcus sp, Salmonella sp, Enterococcus sp e Clostridium sp e quatro de fungos: Candida sp, Aspergillus sp, Penicillium sp, Trichophyton sp. Grande parte desses microrganismos faz parte da microbiota desses animais, mas quando existe uma queda na resistência devido ao estresse causado pela migração, falta de alimento, ou mesmo durante o manejo, podem se tornar doenças graves que se não tratadas podem levar a morte das aves. Por isso, é necessário um diagnóstico prévio, para um tratamento eficaz, fazendo que o sucesso na reintrodução ou realocação seja maior contribuindo assim para conservação das espécies. PALAVRAS-CHAVE:Aves Marinhas; Reabilitação; Fungos; Bactérias; Manejo. FUNGAL AND BACTERIAL GROUPS ISOLATED FROM DEBILITATED SEABIRD´S RESPIRATORY TRACT IN BAIXADA SANTISTA´S COASTAL REGION ABSTRACTIn the Brazilian´s 8000 km of coastline, there is a considerably variety of resident and migratory seabirds. Many of these birds are found weakened on the beaches and are taken to rehabilitation centers for treatment and subsequent release. Some seabirds become vulnerable to bacterial and fungal diseases because the increasing of coastal pollution or because of the management and the captivity stress. Thus, this study aims to describe the main groups of fungi and bacteria in the respiratory tract of seabirds found in coastal region of Baixada Santista -São Paulo (Brasil). Microbiological analyses found six main types of bacteria: Staphylococcus sp., Streptococcus sp, Salmonella sp, Enterococcus sp e Clostridium sp; and four main types of fungi: Candida sp, Aspergillus sp., Penicillium sp., Trichophyton sp.. Most of these microorganisms are part of seabirds' microbiota. When there is a drop in resistance due the stress caused by migration, lack of food, or even during the management the illness can develop, become serious leading the bird´s death. Therefore, it´s necessary a preliminary diagnosis to help in a effective treatment. With the effective treatment there are more chances for a successful in the reintroduction of these seabirds, contributing to species conservation.
Copyrights @ Gunther Brucha, et al.
O Brasil é um dos países que mais utiliza herbicidas no mundo. Seu uso indiscriminado gera efeitos adversos ao meio ambiente e a saúde. O ácido 2,4-Diclorofenoxiacético está entre os 3 princípios ativos de pesticida mais utilizados no Brasil e é empregado em diversas lavouras. Pode ser encontrado em solos superficiais e profundos, sedimentos de rios, lagos, mares, águas fluviais e subterrâneas. O processo aeróbio de biodegradação deste herbicida é conhecido e bem relatado na literatura científica, entretanto pouco se sabe sobre o processo anaeróbio de degradação deste composto. Este trabalho se propõe a aprofundar os estudos relacionados a degradação anaeróbia do 2,4-D. Dessa maneira, o presente estudo teve como objetivo a analisar a degradação do 2,4-D em diferentes condições de oxirredução. Para isso, foram realizados ensaios de enriquecimento das comunidades microbianas anaeróbias metanogênicas, sulfatorredutoras e desnitrificantes, na presença de 2,4-D, utilizando como inóculo o sedimento coletado no reservatório de Itaipú. Os resultados dos ensaios apontam que houve variação de remoção do 2,4-D entre os diferentes meios de oxirredução, sendo 9,26%, para a condição desnitrificantes, 63,33%, para a condição sulfetgênica e 100% no meio para a condição metanogênica. Portanto, o meio metanogênico foi o que apresentou melhores condições para a remediação do herbicida 2,4-D nas condições estudadas. Os resultados apresentados podem contribuir para análise mais completa do comportamento deste composto no meio ambiente, ajudando no desenvolvimento de processos de biorremediação mais eficientes.
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