Hydrolysis of intralipid by pancreatic lipase and phospholipase A2-gel filtration studies

Lipids ◽  
1985 ◽  
Vol 20 (11) ◽  
pp. 765-772 ◽  
Author(s):  
Renée Grataroli ◽  
Monique Charbonnier ◽  
Gilles Nalbone ◽  
Denis Lairon ◽  
Christiane Chabert ◽  
...  
Keyword(s):  
Phospholipase A2 ◽  
Pancreatic Lipase ◽  
Gel Filtration ◽  
Hydrolysis Of

Inhibition of human pancreatic lipase-colipase activity by mixed bile salt-phospholipid micelles

1981 ◽  
Vol 241 (4) ◽  
pp. G328-G336 ◽  
Author(s):  
J. S. Patton ◽  
M. C. Carey
Keyword(s):  
Bile Salt ◽  
Aqueous Phase ◽  
Pancreatic Lipase ◽  
Mixed Micelles ◽  
Gel Filtration ◽  
Gum Arabic ◽  
Time Range ◽  
Salt Solutions ◽  
Phospholipid Micelles ◽  
Hydrolysis Of

Mixed dihydroxy bile salt-phosphatidylcholine (PC) micelles can inhibit the hydrolysis of gum arabic-stabilized long-chain triglyceride emulsions by 10(-8) to 10(-9) M concentrations of human pancreatic lipase and colipase. Trypsin treatment of this colipase preparation did not reverse the inhibition, suggesting that procolipase, as a possible contaminant, was not the inhibitory factor. Human biliary phospholipid-cholesterol liposomes, isolated by gel filtration and redissolved in bile salt solutions, inhibited lipolysis to the same degree as solutions of bile salt containing purified PC. The degree of inhibition depended principally on the species of bile salt present (e.g., taurochenodeoxycholate greater than taurodeoxycholate greater than tauroursodeoxycholate greater than taurocholate). In the absence of bile salt, PC (0.4 mM) liposomes alone were not inhibitory over the physiological time range studied. Bile salt solutions of phosphatidylethanolamine or sphingomyelin also inhibited lipase activity, whereas those containing oleyl alcohol, oleyl aldehyde, oleic acid, and lyso-PC did not. PC molecules were found to partition between the triglyceride emulsion interface and the bulk aqueous phase. Full reversal of inhibition occurred in the presence of phospholipase A2, which hydrolyzed the phospholipids to lysolecithin and fatty acids. Mixed bile salt-phospholipid micelles caused marked decrease in the binding of lipase and colipase to the triglyceride substrate and displaced the proteins into the aqueous phase. The results taken together suggest that colipase binds to certain bile salt-PC associations independent of whether the aggregates are located at the surface of a triglyceride particle as a monolayer or in the bulk aqueous phase as mixed micelles.

scholarly journals Isolation, Purification and Analysis of Pancreatic Lipase from ‘Gallus gallus domesticus’

2020 ◽  
Vol 5 (7) ◽  
pp. 590-594
Author(s):  
Sandhya. B ◽  
Nagamani. T.S
Keyword(s):  
Pancreatic Lipase ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Gallus Gallus ◽  
Gallus Domesticus ◽  
Biodiesel Production ◽  
Gallus Gallus Domesticus ◽  
Pharmaceutical Industries ◽  
Ph Range ◽  
Hydrolysis Of

This article discusses the isolation of pancreatic lipase enzyme from the pancreas of Gallus gallus domesticus. Whereas lipase catalyses the hydrolysis and the synthesis of esters formed from glycerol and long-chain fatty acids. Lipases occur widely in nature, it involves applications like organic syntheses, hydrolysis of fats, oils, modification of fats, flavor enhancement in food processing, detergent industries, pharmaceutical industries, chemical analyses, and biodiesel production. Pancreatic lipase was purified to the homogeneity by 70% saturated Ammonium sulphate further, it was dialysate using the dialysis membrane and then gel filtration chromatography was carried out by Sephadex G-75 and DEAE cellulose. The molecular weight of purified lipase sample was determined by SDSPAGE, it was found to be 98KDa. The lipase was active in the pH range of 5-10 with an optimum pH of 6.0. The optimum temperature for the hydrolysis of olive oil was 37ºC in the range of 25ºC - 50ºC.

Mechanism of Inhibitory Action on Platelet Activation of a Phospholipase A2 Isolated from Lachesis muta (Bushmaster) Snake Venom

1997 ◽  
Vol 78 (05) ◽  
pp. 1372-1380 ◽  
Author(s):  
André L Fuly ◽  
Olga L T Machado ◽  
Elias W Alves ◽  
Célia R Carlinis
Keyword(s):  
Platelet Aggregation ◽  
Enzymatic Activity ◽  
Phospholipase A2 ◽  
Inhibitory Activity ◽  
Thermal Inactivation ◽  
Anticoagulant Activity ◽  
Gel Filtration ◽  
Apparent Molecular Weight ◽  
Crude Venom ◽  
Lachesis Muta

SummaryCrude venom from Lachesis muta exhibited procoagulant, proteolytic and phospholipase A2 activities. A phospholipase A2, denoted LM-PLA2 was purified from L. muta venom to homogeneity, through a combination of chromatographic steps involving gel-filtration on Sephacryl S-200 HR and reverse phase chromatography on a C2/C18 column. LM-PLA2 presented a single polypeptide chain with an isoelectric point at pH 4.7 and apparent molecular weight of 17 kDa. Partial aminoacid sequence indicated a high degree of homology for LM-PLA2 with other PLA2 from different sources.LM-PLA2 displayed a potent enzymatic activity as measured by indirect hemolysis of red blood cells but it was neither lethal when injected i.p. into mice nor did it present anticoagulant activity. Furthermore, LM-PLA2 displayed a moderate inhibitory activity on the aggregation of rabbit platelets induced by low levels of ADP, thrombin and arachidonate. In contrast, platelet aggregation induced by high doses of collagen was strongly inhibited by LM-PLA2 as well as ATP-release. Treatment of the protein with p-bromophenacyl bromide or 2-mercapto-ethanol, as well as thermal inactivation studies, suggested that the platelet inhibitory effect of LM-PLA2 is dependent on its enzymatic activity. Thus, the platelet inhibitory activity of LM-PLA2 was shown to be dependent on the hydrolysis of plasma phospholipids and/or lipoproteins, most probably those rich in phosphatidylcholine. Surprisingly, lyso-phosphatidylcholine released by LM-PLA2 from plasma was shown to preferentially inhibited collagen-induced platelet aggregation, in contrast to other PLA2s, whose plasma hydrolytic products indistinctly affect platelet’s response to several agonists.

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