Fermentation Unit, Institut Pasteur de Tunis, 1002 Tunis Belvédère, Tunisia.
Biotechnol Appl Biochem. 2010 Dec;57(4):139-49. doi: 10.1042/BA20100272.
Yarrowia lipolytica lipase has been assumed to be a good candidate for the treatment of fat malabsorption in patients with pancreatic insufficiency. Nevertheless, no systematic studies on its stability under physiological conditions pertaining to the human GI (gastrointestinal) tract have been published. Stability of various Y. lipolytica lipase powder formulations at various physiological pH values as well as the effect of digestive proteases and bile salts on enzyme activity were investigated. Results were compared with those obtained from another competing fungal lipase sourced from Candida rugosa. Among the studied formulations, Y. lipolytica lipase stabilized with gum arabic and skimmed milk powder was the most promising powder formulation. Under acidic conditions (pH 3-5), this formulation showed higher stability than those observed with the other Y. lipolytica lipase formulations and C. rugosa lipase. In addition, in the presence of gum arabic and skimmed milk powder as additives, Y. lipolytica lipase exhibited markedly higher resistance to pepsin, trypsin and chymotrypsin actions. Resistance to proteolytic degradation by digestive proteases was also by far higher than that observed with C. rugosa lipase. Similar behaviour was, however, observed when these two fungal lipases were incubated with increased concentrations of bile salts. Residual lipase activity of both fungal lipases showed a slight decrease in NaTDC (sodium taurodeoxycholate) concentration above 4 mM. Consequently, Y. lipolytica lipase formulated with gum arabic and milk powder seemed to have great potential for use as a therapeutic tool for patients with pancreatic insufficiency.
假丝酵母脂肪酶被认为是治疗胰腺功能不全患者脂肪吸收不良的候选药物。然而，目前尚未有关于其在涉及人类胃肠道的生理条件下稳定性的系统研究。本研究考察了不同生理 pH 值下各种假丝酵母脂肪酶粉末制剂的稳定性，以及消化蛋白酶和胆汁盐对酶活性的影响，并将结果与来源于 Candida rugosa 的另一种竞争真菌脂肪酶进行了比较。在所研究的制剂中，用阿拉伯胶和脱脂奶粉稳定的假丝酵母脂肪酶是最有前途的粉末制剂。在酸性条件（pH3-5）下，该制剂比其他假丝酵母脂肪酶制剂和 C. rugosa 脂肪酶表现出更高的稳定性。此外，在添加阿拉伯胶和脱脂奶粉作为添加剂的情况下，假丝酵母脂肪酶对胃蛋白酶、胰蛋白酶和糜蛋白酶的作用表现出明显更高的抗性。对消化蛋白酶的蛋白水解降解的抗性也远高于 C. rugosa 脂肪酶。然而，当这两种真菌脂肪酶与浓度增加的胆汁盐孵育时，也观察到了类似的行为。在 NaTDC（牛磺脱氧胆酸钠）浓度高于 4mM 时，两种真菌脂肪酶的残留脂肪酶活性都略有下降。因此，用阿拉伯胶和奶粉配制的假丝酵母脂肪酶似乎有很大的潜力作为胰腺功能不全患者的治疗工具。
