Fatty acid and positional selectivities of gastric lipase from premature human infants: in vitro studies.
Gastric lipase activity in aspirates from premature human infants was tested for fatty acid and positional selectivity using racemic diacid triacylglycerols (TG) as substrates. The resulting free fatty acids and monoacylglycerols (MG) were recovered and analyzed. Octanoic acid (8:0) and decanoic acid (10:0) were hydrolyzed with a preference of 61.5:1 and 2.4:1 compared to palmitic acid (16:0) from rac-16:0-8:0-8:0 and rac-16:0-10:0-10:0, respectively. The ratio of lauric acid (12:0) to oleic acid (18:1) hydrolyzed from rac-18:1-12:0-12:0 was 13:1. Myristic acid (14:0), 18:1 and linoleic acid (18:2) were released at similar rates. These data and the composition of the MG suggest that, in vitro, the lipase is selective for shorter chain fatty acids and for fatty acids on the primary positions of the TG backbone.
Jensen
R G
RG
Department of Nutritional Sciences, University of Connecticut, Storrs 06269-4017.
deJong
F A
FA
Lambert-Davis
L G
LG
Hamosh
M
M
D002210:Caprylates / Q000378:metabolism; D003652:Decanoic Acids / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism*; D005750:Gastric Juice / Q000201:enzymology*; D006801:Humans; D006868:Hydrolysis; D007231:Infant, Newborn; D007234:Infant, Premature / Q000378:metabolism*; D007850:Lauric Acids / Q000378:metabolism; D019787:Linoleic Acid; D008041:Linoleic Acids / Q000378:metabolism; D008049:Lipase / Q000378:metabolism*; D019814:Myristic Acid; D009227:Myristic Acids / Q000378:metabolism; D019301:Oleic Acid; D009829:Oleic Acids / Q000378:metabolism; D019308:Palmitic Acid; D010169:Palmitic Acids / Q000378:metabolism; D013379:Substrate Specificity; D014280:Triglycerides / Q000378:metabolism
D002210:Caprylates; D003652:Decanoic Acids; D005227:Fatty Acids; D007850:Lauric Acids; D008041:Linoleic Acids; D009227:Myristic Acids; D009829:Oleic Acids; D010169:Palmitic Acids; D014280:Triglycerides; D019814:Myristic Acid; C030358:lauric acid; D019301:Oleic Acid; D019308:Palmitic Acid; C031071:decanoic acid; D019787:Linoleic Acid; D008049:Lipase; C031492:octanoic acid