• Journal of Microbiology and Biotechnology
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• 제17권6호
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• pp.960-967
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• 2007

The co-immobilization of Aspergillus niger glucose oxidase (GOD) with bovine liver catalase (CAT) onto florisil (magnesium silicate-based porous carrier) was investigated to improve the catalytic efficiency of GOD against $H_2O2$ inactivation. The effect of the amount of bound CAT on the GOD activity was also studied for 12 different initial combinations of GOD and CAT, using simultaneous and sequential coupling. The sequentially co-immobilized GOD-CAT showed a higher efficiency than the simultaneously co-immobilized GOD-CAT in terms of the GOD activity and economic costs. The highest activity was shown by the sequentially co-immobilized GOD-CAT when the initial amounts of GOD and CAT were 10 mg and 5 mg per gram of carrier. The optimum pH, buffer concentration, and temperature for GOD activity for the same co-immobilized GOD-CAT sample were then determined as pH 6.5, 50 mM, and $30^{\circ}C$, respectively. When compared with the individually immobilized GOD, the catalytic activity of the co-immobilized GOD-CAT was 70% higher, plus the reusability was more than two-fold. The storage stability of the co-immobilized GOD-CAT was also found to be higher than that of the free form at both $5^{\circ}C\;and\;25^{\circ}C$. The increased GOD activity and reusability resulting from the co-immobilization process may have been due to CAT protecting GOD from inactivation by $H_2O2$ and supplying additional $O_2$ to the reaction system.

• Korean Chemical Engineering Research
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• 제61권4호
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• pp.576-583
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• 2023

본 연구에서는 전극의 전기 전도도 증대와 젖산 산화반응의 부산물인 과산화수소 생성 완화가 젖산 산화효소 전극 성능에 미치는 영향을 조사하였다. 유연성 있는 탄소종이 표면을 단일벽 탄소나노튜브로 개질하여 전극의 전기 전도도를 향상시켰다. 카탈라아제를 도입하여 젖산 산화반응에서 발생하는 과산화수소를 제거하였다. 젖산 산화효소와 카탈라아제가 동시에 고정화된 탄소종이 전극은 젖산 산화효소만 고정화된 탄소종이 전극보다 1.7배 많은 전류를 생성하였다. 단일벽 탄소나노튜브로 개질된 탄소종이 표면에 젖산 산화효소와 카탈라아제가 동시에 고정화된 전극은 171 µA의 전류를 생산하였는데, 이는 탄소종이 표면에 젖산 산화효소만 고정화된 전극이 생산하는 전류보다 2배 높은 값이다. 최적화된 전극은 젖산 농도가 20 mM까지 선형반응을 보여 센서용 전극으로 사용 가능함을 확인하였다.