Porcine pancreas lipase (PPL) was immobilized on magnetic multiwalled carbon nanotubes successfully for the synthesis of substituted 2H‐chromenes. The catalytic activity of immobilized PPL was much higher than that of free PPL. Effects of reaction medium, temperature, and enzyme dosage were also investigated. Under optimum reaction conditions (acetylacetone (1 mmol), salicylaldehyde (1 equivalent), methanol (10 equivalent), and immobilized PPL (protein content: 30 mg; 65 °C; DMF 5 mL; 5 H), the immobilized PPL showed an excellent catalytic performance on the synthesis of substituted 2H‐chromenes. Moreover, the immobilized PPL exhibited satisfactory thermostability, operational simplicity, and reusability in this reaction.

中文翻译：

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固定在磁性多壁碳纳米管上的脂肪酶催化合成取代的2H-色烯

猪胰腺脂肪酶（PPL）已成功固定在磁性多壁碳纳米管上，用于合成取代的2 H-色烯。固定化PPL的催化活性远高于游离PPL。还研究了反应介质，温度和酶用量的影响。在最佳反应条件下（乙酰丙酮（1 mmol），水杨醛（1当量），甲醇（10当量）和固定化的PPL（蛋白质含量：30 mg; 65°C; DMF 5 mL; 5 H），固定化的PPL显示出取代的2 H-色烯的合成具有出色的催化性能，而且固定化的PPL在此反应中表现出令人满意的热稳定性，操作简便性和可重复使用性。