DEFAR - Departamento de Farmácia

URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/530

Navegar

Filtros

2006 - 200912020 - 20221

Configurações

Assunto: search.filters.subject.Sulfate-reducing bacteria

Resultados da Pesquisa

Agora exibindo 1 - 2 de 2
  • Nenhuma Miniatura Disponível
    Item
    Biological factors influencing As mobilization from an ancient mining region : in vitro studies.
    (2022) Santos, Alcylane Caldeira; Lopes, L. R.; Teixeira, Mônica Cristina
    Ouro Preto city is located in the Iron Quadrangle, where Arsenic-bearing minerals are easily found; therefore, human exposure to As is a concern. The aim of this study was to assess the influence of organic matter (OM) and microbiota on As mobility. Soil samples were collected from deactivated gold mines to achieve this goal. Soil aliquots (5 g) were exposed to different extractant mixtures: CaCl2, 2.5 mmol −1 (A); CaCl2 + 5 g of proteic biomass - PB (B); CaCl2 + bacterial inoculum (C); CaCl2 + 5 g of PB + inoculum (D); and organic acid solution - OAS (0.1 mol−1) (E). Solubility tests were conducted at room temperature for 120 days (A–D) or 48 h (E). PB increased As mobility up to 600 times compared to that of the control group (A). As mobility in the presence of bacteria was slightly lower thus highlighting the effects of microbiota and OM on As mobilization. Principal component analyses indicated Ca, Fe, Mn, P, Mg, Sr, As, and Cd were the main contributing factors. In the presence of OM, Zn, Cu, Pb, Cd, As, and Cr were leached. The positive effect of OM and indigenous microorganisms on As mobility was confirmed, reinforcing the need to adopt preventive measures to avoid potential environmental damage due to ineffective management of urban and industrial waste deposition in such As-contaminated urban areas.
  • Nenhuma Miniatura Disponível
    Item
    Specific growth rate of sulfate reducing bacteria in the presence of manganese and cadmium.
    (2006) Medírcio, Silvia Nicolato; Leão, Versiane Albis; Teixeira, Mônica Cristina
    The development of technologies based on the use of sulfate-reducing bacteria (SRB) to treat sulfate contaminated wastewaters has produced a cost-effective route to precipitate metals. In this work the effects of cadmium and manganese in the SRB growth rates were assessed. It was observed that duplication time is 50 h in the presence of cadmium and 6 h in the presence of manganese, thus showing that the SRB growth rate was more affected by the presence of cadmium. A low sulfate reduction (maximum 25%) occurred which was sufficient for metal precipitation. The results are discussed considering their implications for metal precipitation in acid mining drainage.