Effect of bioaugmentation with Paenibacillus spp. and thin slurry recirculation on microbial hydrolysis of maize silage and bedding straw in a plug-flow reactor

Abstract In this work, the effect of bioaugmentation on hydrolysis and acidogenesis efficiency bedding straw mixed with maize silage is examined. A plug-flow bioreactor was operated for 70 weeks as a reference feedstock subsequently an increasing content 30% 66% (w/w). Bioaugmentation two Paenibacillus species conducted at each process condition to investigate impact recalcitrant lignocellulosic feedstock. stable acidogenic digestion substrates achieved, during which acetic butyric acid were accumulated main byproducts. Specific rates between 258 264 gO 2 kg −1 VS determined pure straw, while specific rate decreased 195 when mixture applied. spp. increased by up 41–63% no increase observed straw. Acid production, however, enhanced 21 42% following all substrate mixtures. positive physiological state cultures, recorded frequency-dispersed polarizability, seen after bioaugmentation, remained retention times continuous fermentation mode. Recirculation thin sludge further prolonged effects bioaugmentation. The results work provide basis optimize amount bioaugmented microorganisms biogenic material respect sustainable performance costs.