[Effect of methanosarcina on the growth of primary anaerobes]

The effect of Methanosarcina vacuolata on the mixed celluloytic population and on pure cultures of anaerobic bacteria was studied. In the pasteurized enrichment culture decomposing cellulose but producing no methane, the biomass of primary anaerobes increased at a higher rate when Methanosarcina was introduced; the rate of cellulose hydrolysis did not change. Methanosarcina stimulated also the growth of Escherichia intermedia and Ruminococcus albus on a medium containing glucose and cellobiose. The growth of combined cultures with the production of methane was possible only on a medium with a low content of carbohydrates since an increase in the concentration of glucose inhibited the growth of Methanosarcina.