The hydrolysis of lignocellulose is assumed to be the rate-limiting step in the anaerobic fermentation process. A\r\nfungal hydrolytic enzyme mixture was used to assess the enzymatic impact on different feedstocks for biogas production. The\r\noptimal conditions for enzymatic hydrolysis of rye grain silage, maize silage, grass silage, feed residues and solid cattle manure\r\nwere determined in lab-scale experiments. Finally, the effects of enhanced hydrolysis on anaerobic digestion were\r\ninvestigated in batch digestion tests. Enzyme treatment of substrate showed Michaelis-Menten-like behavior and reached\r\nmaximum values after 3 hours for reduced sugars as a product of hydrolysis. Methane production potential was determined\r\nfor specific feedstock mixtures without enzyme, with inactivated enzyme and with active enzyme (with and without buffer).\r\nThe results obtained show a clear increase in methane production after enzyme application for solid cattle manure (165 LN\r\nCH4�·kgODM\r\n-1 to 340 LN CH4�·kgODM\r\n-1 ), grass silage (307 LN CH4�·kgODM\r\n-1 to 388 LN CH4�·kgODM\r\n-1; enzyme plus buffer), feed\r\nresidue (303 LN CH4�·kgODM\r\n-1 to 467 LN CH4�·kgODM\r\n-1), maize silage (370 LN CH4�·kgODM\r\n-1 to 480 LN CH4�·kgODM\r\n- 1) and a lower\r\nincrease for rye grain silage (355 LN CH4�·kgODM\r\n-1 to 413 LN CH4�·kgODM\r\n-1). The ratios of heating values from methane yields to\r\nheating values from the dry materials ranged between 0.3 and 0.7 for the untreated feedstock and increased to levels between\r\n0.6 and 0.9 after the different forms of enzyme application.
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