In Vitro Sensitivity of Probiotics to Human Pancreatic Juice

BACKGROUNDThe resistance of gut flora with probiotic activity to pancreatic juice is usually tested with artificial pancreatic fluid. Previous studies evaluated the sensitivity of diverse probiotics to human gastric and biliary secretion; none tested the resistance of probiotics to human pancreatic juice. As most bacteria sensitive to artificial pancreatic fluid in vitro have a high rate of isolation from feces, the resistance to human pancreatic juice could be higher. AIMThe aim of this study was to compare the sensitivity of different strains of probiotics to artificial and human pancreatic juice. MATERIALS AND METHODSThe viability of 8 strains of Lactobacillus and 4 strains of Bifidobacterium was tested with standard artificial and human pancreatic juice withdrawn from 16 patients during endoscopic retrograde cholangiopancreatography procedure. The mortality rate (%) of various bacteria was measured after 5, 30, and 60 minutes contact time. The results were normalized for mortality rate induced by hypotonic condition and time exposure to 37°C. RESULTSWhen incubated with artificial and human pancreatic juice, the mortality rate of all strains of Lactobacillus at 5, 30, and 60 minutes was 10.1 versus 7.6, 20.5 versus 19.7, and 28.6 versus 29.8, respectively; whereas the mortality rate of all strains of Bifidobacterium was 8.0 versus 9.2, 33.3 versus 28.9, and 42.2 versus 44.4, respectively. CONCLUSIONSAll the tested strains were sensitive to artificial and human pancreatic juice depending on time contact. Bifidobacterium strains seem to be more sensitive than Lactobacillus strains in particular at higher time contact. There is no significant difference between sensitivity to simulated and human pancreatic juice. For this reason, probiotics activity may be tested with artificial pancreatic fluid using a standardized, easier, and less costly procedure.