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Updated: Dec 11, 2025

Medium Preparation for the Cultivation of Microorganisms under Strictly Anaerobic/Anoxic Conditions
Published on: August 15, 2019
Evaluation of dissolved and immobilized redox mediators on dark fermentation: Driving to hydrogen or solventogenic
Marina M Atilano-Camino1, Cindy D Luévano-Montaño1, Alcione García-González1
1Universidad Autónoma de Nuevo León (UANL), Facultad de Ciencias Químicas, Av. Universidad S/N, Cd. Universitaria, C.P. 66455 San Nicolás de los Garza, Nuevo León, Mexico.
Abstract:
In this work, lawsone (LQ) and anthraquinone 2-sulphonate (AQS) (dissolved and covalently immobilized on activated carbon) were evaluated as redox mediators during the dark fermentation of glucose by a pretreated anaerobic sludge. Findings revealed that the use of dissolved LQ increased H2 production (10%), and dissolved AQS improved H2 production rate (11.4%). Furthermore, the total production of liquid byproducts (acetate, butyrate, ethanol, and butanol) was enhanced using dissolved (17%) and immobilized (36%) redox mediators. The established redox standard potentials of LQ and AQS suggested a possible interaction through electron transfer in cytochromes complexes for hydrogen production and the Bcd/EtfAB complex for volatile fatty acid formation.
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