Digital Book
Microbial Electrochemical Cell Technology with Lab Notes
Chapter 2 - Electroactive Biofilms
Author: Prof. Dr. Tunc Catal
Publication Date: 10.01.2026
Publisher: EUCHEMBIOJ Publishing Platform
DOI:
10.62063/2026-mfc-c2
Type:
Applied Handbook
Field:
Biotechnology, Bioelectrochemistry
ABSTRACT
The structure, role, and ecological importance of electroactive biofilms—the foundation of microbial electrochemical technologies—are examined in this chapter. Electroactive microorganisms create intricate biofilm structures that can transfer electrons to conductive surfaces via soluble redox mediators, nanowires, or direct contact. Environmental factors, microbial community dynamics, and electrode surface characteristics all have a significant impact on the formation of biofilms and the efficiency of electron transfer. The chapter describes the various electron transport mechanisms of important exoelectrogenic genera, such as Geobacter and Shewanella, which are aided by cytochromes, mediators, or conductive pili. There is also discussion of the meth ods used to identify and characterize these microorganisms, including electrochemical and microscopy techniques as well as molecular analyses. A foundation for optimizing biofilm-driven applications in energy generation, bioremediation, and the synthesis of value-added compounds is provided by an understanding of these mechanisms.
Keywords
Electroactive biofilms; Exoelectrogenic microorganisms; Biofilm architecture; Redox-active mediators; Anodic biofilm dynamics
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