This study explored the hydrolysis and fermentation of paper with hydrogen (H-2) and volatile fatty acid (VFA) recovery using a natural microbial consortium added to lysimeters. Serial dilutions of rumen fluid in natura were performed to obtain a fermentative nonmethanogen consortium, which was used as inoculum in lysimeters under two different incubation temperatures, Ll at 35 degrees C and L2 at 55 degrees C. H-2 was detected in both lysimeters: 791.5 mL (L1) and 70.4 mL (L2). In L1, the production of 16,856 mg L-1 acetic acid was likely due to the occurrence of homoacetogenesis. Under thermophilic conditions, L2, a low volume of H2 was detected, and the highlight was the production of ethanol and methanol at 2289 and 5614 mg L-1, respectively. According to the Shannon index, there was great diversity of microorganism populations in the rumen fluid in natura (6.34) compared with the purified rumen fluid (2.73), L1 (2.67) and L2 (3.21). The most abundant genus in the rumen fluid in natura was Prevotella (37.5 %); in the purified consortium (68.7 %) and L1 (63.8), Dysgonomonas; and in L2 (88.7 %), Thermicanus. In conclusion, the temperature influenced the microbial community structure, the metabolic route and, consequently, the main byproducts produced by the fermentative activity at 35 degrees C and 55 degrees C. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.