The aim of this work was to develop and study the performance of a packed bed immobilized enzyme reactor for the effective removal of urea in high polyphenol wines. Purified acid urease from Lactobacillus fermentum was immobilized on Eupergit® C 250 L yielding a biocatalyst with enzyme loading and specific activity per g of dry support of 109.7 ± 2.4 mg and 677 ± 39 IU, respectively. Incubation of the developed biocatalyst at 20 °C in rosé and red wines resulted in a two-phase deactivation mechanism, with a residual asymptotic activity after about 170 h of 67% and 24%, respectively. The developed biocatalyst was used in a packed bed reactor with recycling to efficiently remove urea from rosé and red wines. A model for the bioreactor allowed to estimate the apparent pseudo-first order kinetic constant for urea hydrolysis, which for three repeated bioconversion cycles varied in the range 2.8–4.1 cm³ g⁻¹ min⁻¹ for the rosé wine and 1.1–2.7 cm³ g⁻¹ min⁻¹ for the red wine. Results of repeated bioconversion cycles allowed to conclude that enzyme deactivation by phenols is the main reason for the low urease activity observed in high polyphenol wines. This suggested the use of immobilization as a means to overcome the present limitations in the use of the free enzyme.

这项工作的目的是开发和研究填充床固定化酶反应器用于有效去除高多酚葡萄酒中尿素的性能。发酵乳杆菌纯化的酸性脲酶将其固定在C 250 L上，得到一种生物催化剂，每克干支持物的酶负载和比活性分别为109.7±2.4 mg和677±39 IU。在20°C的桃红葡萄酒和红酒中培养发达的生物催化剂会导致两相失活机制，约170小时后的残留渐进活性分别为67％和24％。研发的生物催化剂可用于填充床反应器中，并进行回收利用，以有效地从桃红和红酒中去除尿素。生物反应器的模型可以估算尿素水解的表观拟一级动力学常数，这三个重复的生物转化循环在桃红葡萄酒中在2.8–4.1 cm ³ g ^-1 min ^-1和1.1–2.7 cm的范围内变化³克红酒^-1分钟^-1。重复生物转化循环的结果可以得出这样的结论：酚引起的酶失活是高多酚葡萄酒中观察到的脲酶活性低的主要原因。这表明使用固定化作为克服使用游离酶的当前限制的手段。