著者

Takashi KIMURA Masahiro YOSHIDA Kayoko OISHI Masafumi OGATA Teruo NAKAKUKI

出版者

Japan Society for Bioscience, Biotechnology, and Agrochemistry

雑誌

Agricultural and Biological Chemistry (ISSN:00021369)

巻号頁・発行日

vol.53, no.7, pp.1843-1848, 1989 (Released:2006-04-05)

参考文献数

17

被引用文献数

2 9

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A dual enzyme system of exo-maltotetraohydrolase [EC 3.2.1.60] and pullulanase [EC 3.2.1.41] was studied for the continuous production of maltotetraose. Porous chitosan beads were selected from among many carriers as the best carrier to immobilize both enzymes. The properties of the immobilized enzymes were examined and compared with those of the native enzymes. For exo-maltotetraohydrolase, the optimum pH of the immobilized enzyme shifted slightly to the acidic side and the pH stability was improved on the alkaline side. The optimum temperature of the immobilized enzyme increased by about 15°C and thermostability was improved by about 10°C. As for pullulanase, very little difference in thermostability was observed. The effects of operating conditions on the continuous production of maltotetraose using exo-maltotetraohydrolase immobilized on the porous chitosan beads were examined. Porous chitosan beads were recognized to be superior to Diaion HP-50. The continuous production of maltotetraose was accomplished using the dual immobilized enzyme system. The dual enzyme system proved to be effective to increase the maltotetraose content in the product. A stable operation was successfully continued for more than 60 days.