Maize is grown in large quantities for nutritional purpose; its agricultural by-product is the corn stover, which is usually unused. Because of its high abundance and high cellulose content, it is a promising substrate for biogas production. However, this cellulose-rich biomass is not used in anaerobic fermentors today, due to its insolubility. It forms a solid crust at the top of the liquid ph...

Errors are usually made in the quantification of biogas from lab scale anaerobic digestion experiments. This paper deals with the application of a manometric transducer associated with a pressure feedback control system to the estimation of the biogas produced from an anaerobic fermentation of primary sludge. The estimation procedure is reliable and convenient for on-line monitoring of gas prod...

Paper mill effluent (PME) was used as an organic feedstock for production of biohydrogen via dark fermentation using heat-shock pretreated anaerobic sludge under mesophilic conditions. The influence of substrate concentration (5, 10 and 15 g-COD/L) and the initial pH (5 and 7) on the efficiency of dark hydrogen fermentation from PME were investigated. The highest hydrogen yield of 55.4 mL/g-COD...

Fermentation or anoxic metabolism allows unicellular organisms to colonize environments that become anoxic. Free-living unicellular algae capable of a photoautotrophic lifestyle can also use a range of metabolic circuitry associated with different branches of fermentation metabolism. While algae that perform mixed-acid fermentation are widespread, the use of anaerobic respiration is more typica...

We investigated metabolic engineering of fermentation pathways in Escherichia coli for production of optically pure D- or L-lactate. Several pta mutant strains were examined, and a pta mutant of E. coli RR1 which was deficient in the phosphotransacetylase of the Pta-AckA pathway was found to metabolize glucose to D-lactate and to produce a small amount of succinate by-product under anaerobic co...

We investigated metabolic engineering of fermentation pathways in Escherichia coli for production of optically pure Dor L-lactate. Several pta mutant strains were examined, and a pta mutant of E. coli RR1 which was deficient in the phosphotransacetylase of the Pta-AckA pathway was found to metabolize glucose to D-lactate and to produce a small amount of succinate by-product under anaerobic cond...

Most yeast species can ferment sugars to ethanol, but only a few can grow in the complete absence of oxygen. Oxygen availability might, therefore, be a key parameter in spoilage of food caused by fermentative yeasts. In this study, the oxygen requirement and regulation of alcoholic fermentation were studied in batch cultures of the spoilage yeast Zygosaccharomyces bailii at a constant pH, pH 3....

During six months of experimentation, a plug-flow system without recirculation was employed to study the volatile fatty acids (VFA) production by means of anaerobic fermentation of urban organic wastes. Results showed an important VFA production at mesophilic range of temperature (37°C). Particulary, VFA concentration in the outlet sludge went from 11.8 g/L at 2 days of retention time up to 23....