Lipázy

Lipázy (lipases) are a family of serine hydrolase enzymes that catalyze the hydrolysis of triglycerides into free fatty acids and monoacylglycerols. They function at lipid–water interfaces and are essential for dietary fat digestion and lipid metabolism. In humans, digestive lipases include pancreatic lipase, the principal enzyme in the small intestine, and gastric lipase in the stomach. Pancreatic lipase requires colipase for full activity in the presence of bile salts and micelles. Other lipases operate in specific tissues, such as lipoprotein lipase on the vascular endothelium, hydrolyzing triglycerides in circulating lipoproteins, and hormone-sensitive lipase in adipose tissue, which mobilizes stored fats in response to hormonal signals. The catalytic mechanism typically involves a serine-based catalytic triad (serine, histidine, aspartate) and interfacial activation.

Clinical relevance: Serum lipase is a diagnostic marker for acute pancreatitis; it rises within hours of onset and remains elevated longer than amylase. Measurements aid in diagnosing pancreatic disorders and monitoring disease. Lipase activity is also decreased in exocrine pancreatic insufficiency and certain diseases; conversely, lipase inhibitors such as orlistat are used in obesity management by inhibiting intestinal fat digestion.

Industrial use: Lipases are widely used in biocatalysis, including fat and ester hydrolysis, synthesis of chiral compounds, and biodiesel production; they are employed in detergents and can be immobilized for repeated use.