Data/hora: 10/06/2024 01:05:41

Provedor de dados: | 69
País: | Chile
Título: | Biodegradation of two commercial herbicides (Gramoxone and Matancha) by the bacteria Pseudomonas putida
Autores: | Kopytko,Maria; Chalela,Graciela; Zauscher,Fernando.
Data: | 2002-08-01
Ano: | 2002
Resumo: | The purpose of this project was to evaluate the biodegradation of two commercial herbicides (Gramoxone and Matancha) by the bacteria Pseudomonas putida. Gramoxone’s active ingredient is Paraquat (1,1’-dimethyl-4,4’-bipyridylium) and Matancha’s is 2,4-D (2,4-dichlorophenoxiacetic acid). To carry out the biodegradation experiments, a factorial design 2³ was executed, where the independent variables were: herbicide concentration, nutrient concentration and the use or no use of activated charcoal (AC) in the same experiment with bacteria. Duplicate experiments were performed for a period of three days using 500 ml bioreactors. The best results obtained when no AC was used were: 47,29% degradation for Gramoxone (by UV/VIS) and 68.72% for Matancha (by HPLC). The treatments carried out with the use of AC for either of the two herbicides gave more than 95% degradation at 72 h. In fact, under these conditions most of the experiments showed at least a 90% removal at 24 h. It is clear that the dual combination of adsorption by AC and biological activity by the bacteria was very effective, in particular when at least 10% nutrients were added. The statistical study of the results showed that AC is a highly significant variable, and that there are significant interactions between the three variables used in the experimental design. The application of these experiments to wastewater (COD = 584.11) confirmed that it is possible to remove more than 90% of either of these herbicides in a 24 h period.
Tipo: | Journal article
Idioma: | Inglês
Identificador: | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582002000200013
Editor: | Pontificia Universidad Católica de Valparaíso
Formato: | text/html
Fonte: | Electronic Journal of Biotechnology  v.5 n.2 2002