Crystallization and Characterization of Polyamine Oxidase from Aspergillus terreus

A thin-layer flow cell system for the determination of l-ascorbic acid by an ascorbate electrode was constructed and several components of this system were investigated. The most preferable conditions for optimum operation of the system were as follows: injection volume 150 μ1, delay coil length 60 cm, flow rate 1 ml/min, temperature 20°C, cell spacer thickness 0.2 mm. The linear response region was 0.2-3.0 mm and 0.02-0.5 mm (original l-ascorbic acid concentration) in the cases of pure oxygen and atmospheric oxygen bubbling, respectively. The relative standard variation at 1.5 mm l-ascorbic acid was 3.1 % for 20 successive assays. The measuring time was 2–3 min for each of these assays.