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A new method for disinfection of microorganism by electrochemically regenerated periodate was developed. The oxidation of iodate of periodate was observed at 1.25 V versus a silver/silver chloride electrode in a cyclic voltammogram of potassium iodate and it was found that the survival rate was 0% at 1.25V.

A strain of Alcaligenes faecalis T1, which was isolated from activated sludge, excreted an extracellular poly(3- hydroxybutyrate) depolymerase as it grew in a medium containing poly(3-hydroxybutyrate) as the sole carbon source. The molecular weight of the enzyme, purified from the culture medium to electrophoretic homogeneity, was 48000 as determined by Sephadex G-100 filtration, and 50000 by polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate. The pH optimum for the enzyme reaction was 7.5. The purified enzyme depolymerized poly(3-hydroxybutyrate) purified from Zoogloea rwnigera I-16-M. but did not attack the bacterial native poly(3- hydroxybutyrate)-containing granules. Km values were 13.3 μg/ml (= 0.78 μM, based on an estimated average molecular weight of 17000) for poly(3-hydroxybutyrate) and 5.4mM for the trimeric ester of n(-)-3-hydroxybutyric acid. Analysis of hydrolytic products of poly(3-hydroxybutyrate), several oligomeric esters of n(-)- 3 -hydroxybutyric acid, and the methyl ester of the trimeric ester indicated that the enzyme hydrolyzed these substrates from the free hydroxyl terminus, releasing n(-)-3-hydroxybutyrate dimer units one at a time. [ABSTRACT FROM AUTHOR]