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1.
An Acad Bras Cienc ; 90(2): 1327-1336, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29768570

RESUMEN

One of the most prominent fields of environmental chemistry is the study and the removal of micro-pollutants from aqueous matrices. Analytical techniques for their identification and quantification are becoming more sensitive and comprehensive and, as a result, an increasing number of drugs have been detected in environmental samples. However, the literature shows that conventional treatments for drinking water and wastewater are not sufficient for remove these compounds. This study aims to check whether the process of hydrothermal carbonization (CHT) is effective in removing the synthetic sex hormones: ethinyl estradiol, gestodene and cyproterone acetate from aqueous samples. The system used in CHT basically consists of a pressurized reactor made of stainless steel and solutions of compounds of interest, both individual and mixed, with a concentration of 1.0 µg.L-1 and a pH range of 2.0 to 3.0. The maximum surface temperature in the reactor was about 180 °C, the internal pressure was 20 bar with 90 minutes for the reaction. Four experiments were conducted, one for each hormone and one with the three hormones together. In individual tests removal of the compounds was found to be 99.8% for ethinyl estradiol, 99.3% for gestodene and 100% for cyproterone acetate. For a mixture of the hormones treated under the same conditions, the mean values of CHT-removal of Ethinylestradiol, Gestodene and Cyproterone Acetate were 99.60%, 96.80% and 68.90%, respectively. The impact of the matrix effect may have affected the efficiency of the hormone removal process by CHT.


Asunto(s)
Carbono , Acetato de Ciproterona/química , Restauración y Remediación Ambiental/métodos , Etinilestradiol/química , Calor , Norpregnenos/química , Cromatografía Liquida
2.
Prep Biochem Biotechnol ; 48(6): 541-548, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29939831

RESUMEN

Bioremediation is a strategy to mitigate environmental impacts of hazardous pollutants from anthropogenic sources. Natural byproducts, including agroindustrial wastes (AW) can be used to induce enzyme biosynthesis, leading up to enhancement of pollutants degradation process. Therefore, this study aimed to evaluate the use of cupuaçu, Theobroma grandiflorum AW as Pycnoporus sanguineus Laccase (Lac) inducer in order to promote 17-α-ethinylestradiol (EE2) bioremediation. The macro and micro-nutrients levels of cupuaçu AWs were evaluated in order to establish further correlations with enzymatic biosynthesis induction. The fungus was cultivated for 7 days in temperature of 28 ± 2 °C and agitation of 150 rpm. For bioremediation, Lac enzymatic extract was added to EE2 solution (10 µg mL-1) and the percentage of removal was evaluated by HPLC after 1-24 hr of reaction. At optimized conditions, the enzyme extract production was remarkably enhanced by adding only 1% (w/v) of cupuaçu AW. Lac activity reached 1642 U mL-1 on the 6th day of culture, which was higher than positive control (511 U mL-1). 86% of EE2 removal was reached after 4 hr, and after 8 hr of reaction, 96.5% was removed. Analysis by direct infusion in MS-ESI-TOF exhibited intermediary compounds formed by radical hydroxilation.


Asunto(s)
Biodegradación Ambiental , Cacao/metabolismo , Contaminantes Ambientales/metabolismo , Etinilestradiol/metabolismo , Lacasa/biosíntesis , Pycnoporus/enzimología , Medios de Cultivo/química , Inducción Enzimática , Proteínas Fúngicas/análisis , Electroforesis en Gel de Poliacrilamida Nativa , Azúcares/análisis , Temperatura
3.
Braz J Microbiol ; 40(4): 790-4, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24031426

RESUMEN

Enzyme application in biotechnological and environmental processes has had increasing interest due to its efficiency, selectivity and mainly for being environmentally healthful, but these applications require a great volume of enzymes. In this work the effect of different concentrations of ethanol and 2,5-xylidine on growth and production of laccase by Pycnoporus sanguineus was investigated. In a medium containing 200 mg.L(-1) of 2,5-xylidine or 50 g.L(-1) of ethanol, the maximum activity of laccase was 2019 U.L(-1) and 1035 U.L(-1), respectively. No direct correlation between biomass and activity of laccase was observed for any of the inducers used during the tests. Ethanol concentrations, larger than or equal to 20 g.L(-1), inhibited the radial growth of P. sanguineus. This study showed that ethanol, which has less toxicity and cost than the majority of the studied inducers, presents promising perspectives for laccase production by P. sanguineus.

4.
Braz. j. microbiol ; 40(4): 790-794, Oct.-Dec. 2009. graf
Artículo en Inglés | LILACS | ID: lil-528161

RESUMEN

Enzyme application in biotechnological and environmental processes has had increasing interest due to its efficiency, selectivity and mainly for being environmentally healthful, but these applications require a great volume of enzymes. In this work the effect of different concentrations of ethanol and 2,5 - xylidine on growth and production of laccase by Pycnoporus sanguineus was investigated. In a medium containing 200 mg.L-1 of 2,5 - xylidine or 50 g.L-1 of ethanol, the maximum activity of laccase was 2019 U.L-1 and 1035 U.L-1, respectively. No direct correlation between biomass and activity of laccase was observed for any of the inducers used during the tests. Ethanol concentrations, larger than or equal to 20 g.L-1, inhibited the radial growth of P. sanguineus. This study showed that ethanol, which has less toxicity and cost than the majority of the studied inducers, presents promising perspectives for laccase production by P. sanguineus.


Asunto(s)
Biomasa , Enzimas Reparadoras del ADN/análisis , Etanol/análisis , Hongos/enzimología , Hongos/genética , Técnicas In Vitro , Lacasa/análisis , Activación Enzimática , Métodos , Fenómenos Biológicos , Métodos
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