Exploring instability mechanisms for mesophilic anaerobic digestion of food waste under overload stress by metagenomic approach

To further clarify instability mechanisms, it induced overload to the reactors with step-type disturbances of OLR and combined the dynamic changes of genes, process parameters and kinetics parameters. The results showed that the degradation kinetics of acetate and propionate and the genes encoding several metabolic enzymes significantly declined in advance. The accumulation of acetate might be owing to continuous decline of kacetate which was attributed to the inhibition of cdhC gene expression and upregulation of metF gene in the metabolism pathways of acetate oxidation. The accumulation of propionate was owing to continuous decline of kpropionate which was attributed to the inhibition of related gene (prpE gene, ACADM gene, paaF gene, PCCA gene, MCEE gene and sucD gene) expression in the metabolism pathways of propionate oxidation.