Production of Bacterial Proteins from Cellulosic Materials

An aerobic mesophilic Pseudomonas sp. isolated from activated sludge degraded different cellulosic materials to varying‐degrees. The degradability was mostly influenced by the lignin content and the crystalline nature of the substrate. Filter paper and cotton fibres, containing little lignin, were degraded maximally. Lignin‐rich Pinus and Larix needles were digested to a lesser extent. There was a difference between natural substrates and substrates that had undergone industrial treatment. At maximal protein production, the isolate converted 11–40% (w/w) of cellulosic substrates into proteins. Alkali treatment of the substrates had only little effect. Cellulose contained in pig‐waste was also degraded by the isolate. At first there was a period of protein production, but after long incubation, the efficiency of conversion of cellulose to protein decreased.