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- Acevedo, F., et al.
(författare)
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A practical culture technique for enhanced production of manganese peroxidase by Anthracophyllum discolor Sp4
- 2011
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Ingår i: Brazilian archives of biology and technology. - 1516-8913 .- 1678-4324. ; 54:6, s. 1175-1186
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Tidskriftsartikel (refereegranskat)abstract
- In this study, different growth conditions of Anthracophyllum discolor Sp4 including the effect of agitation, additions of lignocellulosic support, inducer and surfactant were evaluated on the MnP production in Kirk medium using a culture system made up of the tubes containing the glass bead. The highest MnP production (1,354 U/L on day 13) was obtained when the medium was supplemented with wheat grain and 0.25 mM MnSO 4 as inducer, under static conditions at 30°C. Two isoenzymes were purified (35 and 38 kDa respectively). MnP presented a maximal activity in the pH range between 4.5 and 5.5, a relatively high temperature tolerance (50°C) and a high catalytic activity for 2,6-dimethoxyphenol and hydrogen peroxide.
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2. |
- Tortella, G.R., et al.
(författare)
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Chlorpyrifos degradation in a biomixture of biobed at different maturity stages
- 2012
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 88:2, s. 224-228
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Tidskriftsartikel (refereegranskat)abstract
- The biomixture is a principal element controlling the degradation efficacy of the biobed. The maturity of the biomixture used in the biobed affects its overall performance of the biobed, but this is not well studied yet. The aim of this research was to evaluate the effect of using a typical composition of Swedish biomixture at different maturity stages on the degradation of chlorpyrifos. Tests were made using biomixture at three maturity stages: 0d (BC0), 15d (BC15) and 30d (BC30); chlorpyrifos was added to the biobeds at final concentration of 200, 320 and 480mgkg -1. Chlorpyrifos degradation in the biomixture was monitored over time. Formation of TCP (3,5,6-trichloro-2-pyrinidol) was also quantified, and hydrolytic and phenoloxidase activities measured. The biomixture efficiently degraded chlorpyrifos (degradation efficiency >50%) in all the evaluated maturity stages. However, chlorpyrifos degradation decreased with increasing concentrations of the pesticide. TCP formation occurred in all biomixtures, but a major accumulation was observed in BC30. Significant differences were found in both phenoloxidase and hydrolytic activities in the three maturity stages of biomixture evaluated. Also, these two biological activities were affected by the increase in pesticide concentration. In conclusion, our results demonstrated that chlorpyrifos can be degraded efficiently in all the evaluated maturity stages. © 2012 Elsevier Ltd.
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3. |
- Urrutia, C., et al.
(författare)
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Influence of the rhizosphere in a biopurification system on the dissipation of a pesticide mixture
- 2015
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Ingår i: Journal of Soil Science and Plant Nutrition. - : Sociedad Chilena de la Ciencia del Suelo. - 0718-9508 .- 0718-9516. ; 15:4, s. 914-927
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Tidskriftsartikel (refereegranskat)abstract
- In a biopurification system such as a biobed, the rhizosphere of the grass layer may be a significant factor for promoting pesticide dissipation in the biomixture. The rhizosphere effect of a Lolium perenne, Festuca arundinacea and Trifolium repens mixture on the dissipation of a pesticide combination that was composed of atrazine, chlorpyrifos and isoproturon was studied. The assay was performed using glass pots divided into two separate compartments (root surface and root-free), each filled with an organic biomixture (oat husk, top soil and peat) and contaminated with the pesticide mixture at 5 mg kg-1. Non-planted and noncontaminated pots were also used as controls. The results indicated that there were high atrazine, chlorpyrifos and isoproturon dissipation in the planted pots compared with the unplanted pots. An inverse correlation was found throughout the assay between phenoloxidase activity and residual pesticide (r=0.684 to 0.952). Indeed, fungal biomass was positively correlated with phenoloxidase activity on day 1 (r =0.825) and day 30 (r =0.855). Besides, exudation of oxalic and malic acid in contaminated pots was higher than in the control without pesticides, associated with oxidation of the pesticide mixture in the biomixture of a bioded system. Therefore, the grass layer enhances pesticide removal in biobeds
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