Pure Cultures and Mixed Microbial Communities

Both mixed and pure cultures can be used for the establishment of biological anodes or cathodes. From a practical point of view, mixed-culture electrodes seem to be more robust and resilient. Several groups have observed a higher power output when comparing mixed and pure culture systems [56]. This could be explained by either synergistic effects or the presence of a more productive exoelectrotroph in the mixed culture biofilms [56, 117]. However, several other scenarios could have occurred, such as pH effects and underdeveloped biofilms of the pure cultures [56]. 

Pure cultures are ideal for studying fundamental aspects or for the catalysis of species-specific reactions. Thrash and Coates gave an overview of pure cultures used in BBSs and suggested that these kinds of studies will help us understand the means by which we can stimulate microbial communities to use electric current [81]. Furthermore, a completely new apphcation would be the use of pure isolates 

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