THE ANAEROBIC OXIDATION OF HYDRAZINE - A NOVEL REACTION IN MICROBIAL NITROGEN-METABOLISM

Hydrazine is rarely found as an intermediate in microbial nitrogen con versions. In this study the conversion of hydrazine by the anaerobic a mmonium oxidation (Anammox) culture, in which hydrazine has been propo sed as an intermediate, was investigated. This study demonstrated the biological nature of hydrazine conversion by the Anammox culture. In b atch cultures with hydrazine it was observed that 3 mol N2H4 was dispr oportionated to 4 mol NH4+ and 1 mol Na-2. Hydrazine with nitrite as a n electron acceptor showed a conversion of 3 mol N2H4 and 4 mol NO2- t o 5 mol N-2, with a specific activity of 5.5 nmol min(-1) (mg volatile suspended solids)(-1). Addition of hydrazine to a biofilm reactor for 80 days showed that it was not possible to grow Anammox with hydrazin e. (C) 1998 Federation of European Microbiological Societies. Publishe d by Elsevier Science B.V.