Zum biochemischen Harnstoffabbau in wäßriger Lösung — Übersicht

Abstract

Zum bioeheinischen Hariistoffabbau in wahiger Losung-Ubersieht Sumiiznry: Urea from natural and anthropogenic soiirc.es is one of the niost interesting nitrogen ronipoiinds in an aqiiat,ic cmvironmrnt . Rcsults of esperimcntd invcst.igat.ionx are prescntcd for the successive biochemical uiea transformat.ion into riitmtrs via nmmoniuru and nitrite species. Kinrtic models based on :I, cornbindtion of MICHAELIS-MENTEN and MONOD equat~ions have been tlerircd which dcscribe reasonably well the course of the enzymat,ic reactions and t'he concent'ration-time profiles of different N oxydation states. Main factors affecting t,he rates of nitrogen met;tbolization are the init,ial concentrat,ion of ureolytic bacteria, the physica.1 stat,c of the nit,rifging microorganisms, and the concentration of toxic orgiinics added to the system under study.

Seasonal variation in sediment urea turnover in a shallow estuary

“…Bacterial decomposition of organic material can also lead to urea production (Satoh 1980, Pedersen et al 1993a, and urea is a well-known product of general purine catabolism (Vogels & Van der Drift 1976, Mobley & Hausinger 1989. Human pollution is a potential urea source in coastal marine environments (Paasche & Kristiansen 1982, Gunkel & Jessen 1986, Gunkel et al 1990). Urea is turned over rapidly to yield NH, and CO2 and is therefore of potential importance in the production of NH4+.…”