香豆素类化合物对胃蛋白酶活性的影响研究

目的：基于香豆素类化合物与胃蛋白酶相互作用的研究，探讨香豆素类化合物对胃蛋白酶活性的影响，可能与胃部疾病治疗存在潜在的关系。方法：采用紫外-可见光谱法及福林酚法，以牛血红蛋白为底物，分别用香豆素、4-羟基香豆素、7-羟基香豆素、7-羟基-4-甲基香豆素作为干扰剂与胃蛋白酶混合，测定胃蛋白酶在540 nm处的吸光度值，计算胃蛋白酶表观酶活；在香豆素类化合物-胃蛋白酶体系中添加抗坏血酸，研究抗坏血酸对各体系中胃蛋白酶活性的影响；同时采用紫外-可见光谱法对香豆素类化合物与牛血红蛋白的相互作用光谱特征进行测定。结果：随着香豆素类化合物浓度增加，胃蛋白酶表观酶活呈降低趋势，但趋势略有不同。4-羟基香豆素、7-羟基香豆素、7-羟基-4-甲基香豆素、香豆素对胃蛋白酶的抑制率分别为10.15%～35.92%、7.27%～12.14%、10.58%～29.29%、13.88%～47.13%。添加抗坏血酸的4-羟基香豆素、7-羟基香豆素和7-羟基-4-甲基香豆素体系与未添加抗坏血酸的香豆素类化合物-胃蛋白酶体系相比，胃蛋白酶表观酶活进一步降低，而添加抗坏血酸的香豆素-胃蛋白酶体系与未添加抗坏血酸的香豆素-...

Investigation of Effects of Coumarin Compounds on Pepsin Activity

Objective: Based on the study of the interaction between coumarin compounds and pepsin, to investigate the effect of coumarin compounds on pepsin activity, which may have potential relationship with the treatment of stomach diseases. Methods: Using UV visible spectroscopy and Folin phenol method, bovine hemoglobin was used as substrate, coumarin, 4-hydroxy-coumarin, 7-hydroxy-coumarin and 7-hydroxy-4- methyl-coumarin were used as interference agents to mix with pepsin. The absorbance values of pepsin at 540 nm were determined, and the apparent enzyme activity of pepsin was calculated. The effects of ascorbic acid on pepsin activity in coumarin compounds-pepsin systems were studied by adding ascorbic acid. The interaction between coumarin compounds and bovine hemoglobin was determined by UV-VIS spectroscopy. Results: With the increase of coumarin compounds concentration, the apparent enzyme activity of pepsin decreased, but the trend was slightly different. The inhibition rates of 4-hydroxy-coumarin, 7-hydroxy-coumarin, 7-hydroxy-4- methyl-coumarin and coumarin on pepsin were 10.15%-35.92%, 7.27%-12.14%, 10.58%-29.29% and 13.88%- 47.13%, respectively. Compared with the coumarin compounds-pepsin systems without ascorbic acid, the 4-hydroxy-coumarin, 7-hydroxy-coumarin, 7-hydroxy-4-methyl-coumarin systems added with ascorbic acid further decreased the apparent enzyme activity of pepsin, while the coumarin-pepsin system with ascorbic acid increased the apparent enzyme activity of pepsin compared to the coumarin-pepsin system without ascorbic acid. Conclusion: Four kinds of coumarin compounds can inhibit pepsin activity. Ascorbic acid inhibits pepsin in 4-hydroxy-coumarin, 7-hydroxy-coumarin, 7-hydroxy-4-methyl-coumarin and pepsin systems, while promoting pepsin activity in coumarin-pepsin system. Four coumarin compounds also interact with bovine hemoglobin, which indirectly affects pepsin activity.