Biotransformation of 4-nitrophenol by co-immobilized Geobacter sulfurreducens and anthraquinone-2-sulfonate in barium alginate beads. (April 2019)

• Record Type: Journal Article
• Authors: Rodriguez, Sujei Y.; Cantú, Maria E.; Garcia-Reyes, Bernardo; Garza-Gonzalez, Maria T.; Meza-Escalante, Edna R.; Serrano, Denisse; Alvarez, Luis H.
• Is Part Of: Chemosphere. Volume 221(2019)
• Page Start: 219
• Page End: 225
• Publication Date: 2019-04
• Subjects: Barium alginate beads -- G. sulfurreducens -- 4-nitrophenol -- Biotransformation -- Redox mediator; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2019.01.041
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Geobacter sulfurreducens and anthraquinone-2-sulfonate (AQS) were used suspended and immobilized in barium alginate during the biotransformation of 4-nitrophenol (4-NP). The assays were conducted at different concentrations of 4-NP (50–400 mg/L) and AQS, either in suspended (0–400 μM) or immobilized form (0 or 760 μM), and under different pH values (5–9). G. sulfurreducens showed low capacity to reduce 4-NP in absence of AQS, especially at the highest concentrations of the contaminant. AQS improved the reduction rates from 0.0086 h −1, without AQS, to 0.149 h −1 at 400 μM AQS, which represent an increment of 17.3-fold. The co-immobilization of AQS and G. sulfurreducens in barium alginate beads (AQSi −Gi ) increased the reduction rates up to 4.8- and 7.2-fold, compared to incubations with G. sulfurreducens in suspended and immobilized form, but in absence of AQS. AQSi −Gi provides to G. sulfurreducens a barrier against the possibly inhibiting effects of 4-NP. Highlights: 4-nitrophenol was reduced by Geobacter sulfurreducens at higher concentrations. AQS and Geobacter sulfurreducens were successfully immobilized in alginate beads. Co-immobilization of AQS and cells enhanced the reduction rate of 4-nitrophenol. Alginate bead provides to cells a barrier against the toxics effects of 4-nitrophenol.