CAJ | 학술논문

以磁性石墨烯为载体制备了磁性石墨烯固定化漆酶，考察了固定化漆酶的酶学特性及其对双酚A（BPA）的降解效能。结果表明，氧化石墨烯的比表面积高达726.34 m2·g-1，与游离漆酶相比，经过石墨烯固定化后漆酶对酸的适应能力、耐热性和贮存稳定性均有所提高，pH值2.0~4.0范围内固定化漆酶活性较为稳定；加入变性剂尿素（1 mol·L-1）后，固定化漆酶的相对活性为87%，游离漆酶相对活性仅为63.02%，固定化导致抗变性剂能力增强。固定化漆酶和游离漆酶活性分别在45和40℃时达到最大值。与游离漆酶相比，固定化漆酶最佳反应温度升高了5℃，且在50℃时，固定化漆酶的相对活性依然保持在95.11%；25℃，pH值4.0条件下保存10 d，固定化漆酶活性为最初活性的82.57%；固定化漆酶具有良好的重复利用性，重复利用10次后，漆酶活性仍为最初活性的82.01%。固定化酶的米氏常数Km为5.38×10-4 mol·L-1，较游离酶的大，说明固定化酶与底物的亲和力比游离酶小。磁性石墨烯固定化漆酶具有良好的吸附能力，可吸附-催化氧化水中的 BPA，且石墨烯良好的吸附作用促进了催化反应，水中BPA质量浓度为15 mg·L-1时，经过18 h反应，BPA的去除率能达到82.14%左右。本研究的结果为石墨烯新型材料固定化漆酶及其应用提供了参考。
이자성석묵희위재체제비료자성석묵희고정화칠매，고찰료고정화칠매적매학특성급기대쌍분A（BPA）적강해효능。결과표명，양화석묵희적비표면적고체726.34 m2·g-1，여유리칠매상비，경과석묵희고정화후칠매대산적괄응능력、내열성화저존은정성균유소제고，pH치2.0~4.0범위내고정화칠매활성교위은정；가입변성제뇨소（1 mol·L-1）후，고정화칠매적상대활성위87%，유리칠매상대활성부위63.02%，고정화도치항변성제능력증강。고정화칠매화유리칠매활성분별재45화40℃시체도최대치。여유리칠매상비，고정화칠매최가반응온도승고료5℃，차재50℃시，고정화칠매적상대활성의연보지재95.11%；25℃，pH치4.0조건하보존10 d，고정화칠매활성위최초활성적82.57%；고정화칠매구유량호적중복이용성，중복이용10차후，칠매활성잉위최초활성적82.01%。고정화매적미씨상수Km위5.38×10-4 mol·L-1，교유리매적대，설명고정화매여저물적친화력비유리매소。자성석묵희고정화칠매구유량호적흡부능력，가흡부-최화양화수중적 BPA，차석묵희량호적흡부작용촉진료최화반응，수중BPA질량농도위15 mg·L-1시，경과18 h반응，BPA적거제솔능체도82.14%좌우。본연구적결과위석묵희신형재료고정화칠매급기응용제공료삼고。
Laccase was immobilized on Magnetic Fe3O4/graphenehybrids by the chemical coupling method. The BET of Magnetic Fe3O4/graphene hybrids was 726.34 m2·g-1;The enzymatic properties of the immobilized laccase and its catalytic capacity for BPA degradation were studied. In comparison to free laccase, the immobilized enzyme had better acid adaptability, and thermal and storage stability. Higher activity was observed for immobilized laccase at a pH value range of 2-4;over 95%of the initial activity of immoblized laccase was still observed at 50 ℃. After adding denaturant (1 mol·L-1), the activity of immoblized laccase was still 87%,much larger than that of free laccase(63%). The immoblized laccase possessed excellent reuse ablility, after reused 10 times, the activity of immoblized laccase was still 82.01%. After 10 days, 82.57%of the initial activity of immoblized laccase was retained. The immobilized laccase exhibited good catalytic capacity for removing BPA from aqueous solutions. When the amount of BPA was 15 mg·L-1, the removal efficiency of BPA in water (the concentration of immobilized laccase catalyst was 10 mg·L-1) reached 82%after 18 hours. The results indicated that the excellent absorb ability of graphene had good effect on the remove rate of BPA in water.