麹式培養によるクエン酸醗酵において生産される糖化アミラーゼの回収について

概要

論文の詳細を見る
Fermentation citric acid has been produced in Japan mainly by koji process with sweet potato-pulp and rice-bran as main and subsidiary raw materials, resp. (Terui, 1950). In this process, finished koji contains considerable activity of amylase, especially of saccharifying amylase.With a hope to obtain saccharifying enzyme preparation without lowering the yield of citric acid, some experiments have been carried out.The first extraction with water can be done either directly or after the koji is mixed with milk of lime for partial neutralization. After stepwise extraction with water to obtain ca. 2.5l of combined extract per Kg of wet koji (water content : 70%), lime is added to precipitate calcium citrate. After standing for a while, the mixture is centrifuged. More than 95 per cent of citric acid in the koji extract can be recovered in the precipitate and ca. 75 per cent of saccharifying activity in the supernatant, from which one can obtain saccharifying enzyme preparation by e.g. alcohol precipitation after concentration at 40°C.As the enzyme preparation contains transglucosidase considerably, the attainable degree of saccharification in a 40g/100ml of liquefied corn starch solution is nothigher than 90% Some properties of the preparation are presented in relation to its future use.
社団法人日本生物工学会の論文
1966-03-25