Plant biomass-degrading consortia are sources of enzymes useful for biofuel production. The image is a representation of the development (by sequential batch cultures) and characterization (e.g. by DNA-omic approaches) of these type of consortia. Here, the microbial inoculum (e.g. forest soil) and the substrate (e.g. wheat straw) drive the development of the resulting microbial communities. The nutritional fluxes (e.g. production and consumption of sugars) are represented, as are interactions (synergism and/or competition) that exist within these microbial systems.