Application of porcine lipase secreted by pichia pastoris to improve fat digestion and growth performance of postweaning piglets

The aim of the study was to use Pichia pastoris to express a recombinant porcine lipase gene (pLip). The expression-secretion cassette was constructed using the P. pastoris GAPDH (glyceraldehyde-3-phosphate-dehydrogenase) promoter and an 89-residue prepro-α-factor secretion signal fused to the AOX1 terminator (the pGAPZαA vector). A total of 1,408 bp of pancreatic lipase cDNA was produced, which was located from the position of 4-nt upstream of ATG to 1408-nt inside the intact coding region of the pLip sequence. In an animal trial, three concentrations of recombinant lipase activity (0, 5,000 and 10,000 U/kg) were blended with the basal diet and fed to weaned piglets for six weeks. During the experimental period, the growth performance (bodyweight, feed intake, and feed efficiency) of the test groups was superior to that of the control group (p < 0.05). Furthermore, the group fed the diet blended with 10,000 U/kg of recombinant lipase showed significant (p < 0.05) increases in blood triglyceride (TG) concentration on the seventh day postweaning. These results suggested that the porcine lipase protein yielded by transformed yeast cells may improve fat digestibility and enhance the growth performance in postweaning piglets.