Lipolytic activity of bacterial lipase survives better than that of porcine lipase in human gastric and duodenal content

Abstract

Background/Aims: Treatment of pancreatic steatorrhea with porcine lipase is unsatisfactory because it is rapidly denatured by acidic intraluminal conditions. The aim of this study was to determine if bacterial lipase is resistant to acid denaturation and is active in the presence of bile acids by comparing its stability with that of porcine lipase in gastric and duodenal juice obtained from six patients undergoing a cholecystokinin octapeptide pancreatic function test. Methods: After inactivating native lipolytic activity, both juices were altered to simulate fasting and postprandial conditions in normal patients and patients with pancreatic insufficiency. Gastric juice was adjusted to pH 2, 3, 4, or 6, duodenal juice to pH 4 or 6, and bile acid concentrations to 4 or 12 mmol/L. Nutrients were added to one half of the samples. Initial bacterial or porcine lipolytic concentrations were 25 or 250 U/mL. After a 1-hour incubation at 37 ‡C, lipolytic activity was remeasured. Results: In gastric juice, more bacterial lipolytic activity survived than porcine lipolytic activity at both concentrations in the absence of nutrients and at a concentration of 25 U/mL with nutrients (P <0.05). In duodenal juice, more bacterial lipolytic activity survived than porcine activity at pH 4 under all test conditions (P < 0.05). Conclusions: Bacterial lipolytic activity should survive better within the gastrointestinal lumen than porcine lipolytic activity and be more effective to treat steatorrhea.