Qualitative and quantitative determination of a humic model compound in microbial cultures by cyclic voltammetry
Por:
Cadena A., Texier A.-C., González I., Cervantes F.J., Gómez J.
Publicada:
1 ene 2007
Resumen:
The humic model compound, anthraquinone-2,6-disulfonate (AQDS), was characterized and measured in microbial cultures by cyclic voltammetry (CV). Under the experimental conditions, the formal reduction potential (E0') of the couple AQDS/AHQDS- was found to be of -0.520 V vs. SCE (standard calomel electrode) at pH value of 7.0. Control experiments showed that there were no interferences of the culture medium or the microbial consortium on the quantitative determination of the quinone. The linear equation E0' = -0.294 - 0.032 pH was found, showing that the pH used (7.0-7.8) did not affect significantly the AQDS determination by CV and AHQDS- was the predominant hydroquinone formed. A calibration curve was obtained by plotting current response versus AQDS concentration with a linear correlation (r = 0.999) from 0.2 to 10 mM of AQDS. This technique was applied in a denitrifying culture to establish kinetic profiles for AHQDS-formation coupled to acetate and p-cresol oxidation. CV results showed that organic matter oxidation by the denitrifying sludge was stoichiometrically associated to AQDS reduction into AHQDS-. CV was shown to be a useful tool for monitoring oxidation/reduction processes of quinones occurring in complex microbial media. © Selper Ltd., 2007.
Filiaciones:
Cadena A.:
Departamento de Biotecnología, Universidad Autónoma Matropolitana-Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, C. P. 09340, Mexico
Texier A.-C.:
Departamento de Biotecnología, Universidad Autónoma Matropolitana-Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, C. P. 09340, Mexico
González I.:
Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, C. P. 09340, Mexico
Cervantes F.J.:
Departamento de Ciencias del Agua y dei Medio Ambiente, Instituto Tecnológico de Sonora, Av. 5 de Febrero 818 sur 85000, Cd. Obregón, Sonora, Mexico
División de Ciencias Ambientales, Instituto Potosino de Investigación Cientifica y Tecnológica, Camino a la Presa San Jose 2055, C. P. 78216, San Luis Potosí, Mexico
Gómez J.:
Departamento de Biotecnología, Universidad Autónoma Matropolitana-Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, C. P. 09340, Mexico
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