CAS Key Laboratory of Chemistry of Northwestern Plant Resources, Key Laboratory for Natural Medicines of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences (CAS), Lanzhou 730000, P R China; University of Chinese Academy of Sciences, Beijing 100049, P R China.
CAS Key Laboratory of Chemistry of Northwestern Plant Resources, Key Laboratory for Natural Medicines of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences (CAS), Lanzhou 730000, P R China.
J Chromatogr A. 2020 Mar 29;1615:460711. doi: 10.1016/j.chroma.2019.460711. Epub 2019 Nov 15.
With the increasing demand for lipase inhibitors and new drugs used in the clinical treatment of obesity, it is of great significance to screen lipase inhibitors from traditional Chinese medicines (TCMs) via capillary electrophoresis. In this work, FeO@TiO nanoparticles was fabricated by solvothermal method and employed as an improved magnetic support to immobilize lipase through electrostatic interaction. By the method of transmission electron microscopy, fourier transform infrared spectroscopy and X-ray diffraction, the magnetic nanoparticles were characterized. The immobilized enzyme possessed advantages of a wider range for pH and temperature endurance, better storage stability and reusability. The kinetics performances of the immobilized lipase were studied. When p-Nitrophenyl palmitate (pNPP) was used as enzyme substrate, the Michaelis-Menten constant was calculated to be 2.51 mM and its inhibition constant for Orlistat was ascertained to be 13.41 μM. Ultimately, the established method was applied to lipase inhibitors screening from 6 Tibetan medicines with lipase inhibitory activity and Oxytropis falcate Bunge was screened out for its supreme lipase inhibitory activity. 11 compounds in the Oxytropis falcate Bunge were further screened, five compounds exhibited similar inhibitory activity to Orlistat, and one compound (kaempferol) presented better inhibitory activity than Orlistat, which is the most commonly used drugs to treat obesity in clinic. This work not only developed a method for new anti-obesity drugs discovery, but also provided inspiration for exploring new medicinal value of the TCMs.
随着人们对脂肪酶抑制剂和用于肥胖临床治疗的新药的需求不断增加，通过毛细管电泳从中药中筛选脂肪酶抑制剂具有重要意义。在这项工作中，通过溶剂热法制备了 FeO@TiO 纳米粒子，并将其用作改进的磁性载体，通过静电相互作用固定脂肪酶。通过透射电子显微镜、傅里叶变换红外光谱和 X 射线衍射对磁性纳米粒子进行了表征。固定化酶具有较宽的 pH 和温度耐受性、更好的储存稳定性和可重复使用性等优点。研究了固定化脂肪酶的动力学性能。当以对硝基苯棕榈酸酯（pNPP）为酶底时，计算出米氏常数为 2.51 mM，其对奥利司他的抑制常数为 13.41 μM。最终，该方法被用于从 6 种具有脂肪酶抑制活性的藏药中筛选脂肪酶抑制剂，并筛选出了具有最高脂肪酶抑制活性的麻花艽。进一步筛选了麻花艽中的 11 种化合物，其中 5 种化合物表现出与奥利司他相似的抑制活性，1 种化合物（山奈酚）的抑制活性优于奥利司他，后者是临床上最常用的治疗肥胖症的药物。这项工作不仅开发了一种用于发现新型减肥药的方法，而且为探索中药的新药用价值提供了启示。
