Abstract: Methanosarcina alcaliphilum which is alkalophilic methanogen having the optimum growth pH range of from about 8.1 to about 8.7. This strain exhibits excellent properties such as alkalophilicity and resistance to low temperature. This strain makes it possible to carry out methane fermentation methods at an alkaline pH and at a low temperature conditions. This strain is applied to methane fermentation in treating solid waste and waste water. Moreover, the bacterial concentration thereof in a reactor can be increased within a very short time and, therefore, the size of such a reactor can be made compact.

Abstract: Methanohalococcus alcaliphilum having an optimum growth sodium chloride concentration ranging from about 2.5 to about 3 mole are herein disclosed. The bacteria are halophilic or halophilic and alkalophilic and can be used as the microorganisms which play a central role in the methods of methane fermentation to enhance the efficiency of such a method since the use of the microorganism makes it possible to carry out the method at an alkaline pH, in the presence of salts in a high concentration and at a low temperature.

Abstract: The present invention relates to a method for preparing magnetic powder comprising homogeneous and fine particles using an alkali-producing enzyme. The object of the present invention is to provide a method suitable for preparing magnetic powder comprising relatively small particles, for instance, fine particles having a particle size ranging from 50 to 500 nm. The present invention relates to a method for preparing at least one member selected from the group consisting of iron oxides, iron hydroxides and iron oxyhydroxides which comprises the step of alkalizing a solution containing iron ions utilizing an alkali-producing enzyme and a substrate of the enzyme.According to the present invention, there can be produced magnetite (Fe.sub.3 O.sub.4) and maghemite (gamma-Fe.sub.2 O.sub.3) useful as magnetic powder as well as goethite (alpha-FeO(OH)), hematite (alpha-Fe.sub.2 O.sub.3) and lepidocrocite (gamma-FeO(OH)) useful as the starting materials thereof.