Laboratory of Biocatalysis and Synthetic Biotechnology, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, People's Republic of China.
Appl Biochem Biotechnol. 2013 Aug;170(8):1974-81. doi: 10.1007/s12010-013-0355-3. Epub 2013 Jun 26.
Production of l-menthol by bioprocesses attracts increasing attention nowadays. Herein, we attempted to develop a bioresolution process for production of l-menthol through enantioselective hydrolysis of dl-menthyl benzoate using a newly isolated bacterium from soil samples. Among 129 active soil isolates screened rapidly by thin-layer chromatography, an outstanding bacterial strain numbered ECU2040, which was subsequently identified as Acinetobacter species, was finally selected as our target enzyme producer due to its highest activity and the best enantioselectivity toward l-substrate as confirmed by chiral gas chromatography. The catalytic performance of the cell-free extract from Acinetobacter sp. ECU2040 was preliminarily examined, indicating that its optimal pH and temperature for the reaction were 7.5 and 37 °C, respectively. Under the optimal conditions, the enzymatic reaction was performed on a 1-L scale, affording l-menthol in 48 % yield and 71 % ee.
如今，生物工艺生产 L-薄荷醇引起了越来越多的关注。在此，我们试图通过对 dl-薄荷基苯甲酸酯进行对映选择性水解来开发一种生物转化生产 L-薄荷醇的方法，使用的酶来自于从土壤样本中分离出的新细菌。在通过薄层层析快速筛选的 129 个活性土壤分离物中，编号为 ECU2040 的出色细菌菌株最终被选为我们的目标酶产生菌，因为它的活性最高，并且通过手性气相色谱法确定其对 L-底物的对映选择性最好。初步研究了从不动杆菌 ECU2040 中提取的无细胞提取物的催化性能，表明其反应的最佳 pH 值和温度分别为 7.5 和 37°C。在最佳条件下，在 1L 规模上进行酶反应，得到 48%产率和 71%ee 的 L-薄荷醇。
