好アルカリBacillus sp.産出アルカリプロテアーゼによるX線フィルムのゼラチン膜の分解

概要

論文の詳細を見る
X-ray films contain a large amount of silver as photo sensitive materials. Silver is recovered from used X-ray films by combustion and reused for sensitive materials and other uses. However, a new process is desired bacause of the nasty smell of the combustion.We found that an alkaline protease from Bacillus sp. B21-2 was useful for the recovery of silver from used X-ray films, so the effects of pH, temperature, and enzyme activity on the enzymatic reaction were investigated to obtain appropriate conditions for the decomposition of the felatin layers. The enzymatic reaction was most active at pH 10.5,and was stimulated by increasing enzyme activity or temperature up to 50℃. Under the conditions of 100U/ml, 40℃, and pH 10.5,gelatin layes were decomposed within 10 min. This is much shorter than the conventional enzymatic method or commercial alkaline proteases. Furthermore the results of repeated treatments suggested that a continuous process of recycling silver from used X-ray films feasible.
社団法人日本生物工学会の論文
1987-11-25