Physiological and Technico-Engineering Aspects of Lignocellulose Solid-State Fermentation with Filamentous Fungi

Abstract

The applicability of various solid-state fermentation (SSF) techniques, exemplified by the conversion of cellolignin- and starch- containing biomass is presented. Possible biopulping and protein biosynthesis in the SSF process with multizone air inlet, recirculation and conditioning has been shown. Some advances in process optimization based on the physiology of fungi have been reviewed. The established resistance of basidiomycetes to increased CO2 concentration allowed to regulate biological heat formation by air recirculation and gaseous composition (O2, CO2) correction. The respiration intensity of cells and biological heat elimination depended upon the O2 and CO2 concentration in the aerating gas. The increased CO2 concentration decreased the growth of bacterial pollution during SSF of basidiomycetes. The increased O2 concentration promoted biological delignification. The technological parameters were improved in fed-batch culture. However, the feasibility of these processes on the industrial scale is rather debatable. SSF pro and contra have been discussed.