LAQV-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal.
Biotechnology Division, Research and Development Center, PETROBRAS, Av. Horácio Macedo, 950. Ilha do Fundão, Rio de Janeiro 21941-915, Brazil.
Int J Mol Sci. 2020 Apr 22;21(8):2918. doi: 10.3390/ijms21082918.
The unprecedently high CO levels in the atmosphere evoke the urgent need for development of technologies for mitigation of its emissions. Among the alternatives, the biocatalytic route has been claimed as one of the most promising. In the present work, the carbonic anhydrase from bovine erythrocytes (BCA) was employed as a model enzyme for structural studies in an aqueous phase at alkaline pH, which is typical of large-scale absorption processes under operation. Circular dichroism (CD) analysis revealed a high enzymatic stability at pH 10 with a prominent decrease of the melting temperature above this value. The CO absorption capacity of the aqueous solutions were assessed by online monitoring of pressure decay in a stainless-steel cell, which indicated a better performance at pH 10 with a kinetic rate increase of up to 43%, as compared to non-biocatalytic conditions. Even low enzyme concentrations (0.2 mg g) proved to be sufficient to improve the overall CO capture process performance. The enzyme-enhanced approach of CO capture presents a high potential and should be further studied.
大气中前所未有的高 CO 水平迫切需要开发减排技术。在各种替代方案中，生物催化途径已被认为是最有前途的途径之一。在本工作中，牛红细胞碳酸酐酶（BCA）被用作在碱性 pH 值的水相中的结构研究的模型酶，这是在操作过程中大规模吸收过程的典型条件。圆二色性（CD）分析表明，在 pH 值为 10 时酶具有很高的稳定性，超过该值时，酶的熔点明显下降。通过在不锈钢池中在线监测压力衰减来评估水溶液的 CO 吸收能力，结果表明在 pH 值为 10 时具有更好的性能，动力学速率增加高达 43%，与非生物催化条件相比。即使低浓度的酶（0.2 mg g）也足以提高整个 CO 捕获过程的性能。酶增强的 CO 捕获方法具有很高的潜力，应该进一步研究。
