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PubMed1988

Development of lipase activity in yolk membrane and pancreas of young turkeys.

Two experiments were conducted to determine the development of lipase activity in the yolk membrane (YM) of poults during the embryonic period and in the pancreas during the first 16 days after hatching. A corn-soybean meal diet, formulated to contain 6% supplemental fat was used in both Experiments 1 and 2; two dietary levels (0 or .06%) of sodium taurodeoxycholate (NaTDC) were tested in Experiment 2. Samples of YM and pancreas were collected starting at Day 7 (Experiment 1) and at Day 18 (Experiment 2) of incubation and continued until Day 4 and Day 16 after hatching for YM and pancreas, respectively. Lipase activity was measured titrametrically and tributyrin was used as the reaction substrate. Total lipase activity (TLA) per YM increased from 31 mueq/min at Day 9 of incubation to a maximum of 214 mueq/min at Day 21 and then decreased through Day 4 after hatching. Specific lipase activity as lipase activity per milligram of pancreas dry weight (DW) increased from 3.1 mueq/mgDW/min at Day 27 of incubation to 15.6 mueq/mgDW/min at Day 1 after hatching. This increase continued linearly (P less than .001) to 26.2 mueq/mgDW/min by Day 16 after hatching. The TLA per pancreas averaged 400 mueq/min at Day 1 and increased to 13,000 (Experiment 1) and 8,400 (Experiment 2) mueq/min by Day 16 after hatching. Inclusion of NaTDC in the diet had no effect on pancreatic lipase activity.

Animals↗
PubMed1999

The realm of microbial lipases in biotechnology.

In this review, a comprehensive and illustrious survey is made of the applied aspects of microbial lipases in modern biotechnological practices. Lipases are the most versatile biocatalyst and bring about a range of bioconversion reactions such as hydrolysis, interesterification, esterification, alcoholysis, acidolysis and aminolysis. After a brief description of the microbial sources of lipases, the pivotal role of lipases in the processes and products of the food and flavourings industry is illustrated. An illustration is presented of biomedical applications. The panorama of lipases in the manufacture of fine chemicals is depicted with special emphasis on pharmaceuticals, pesticides, cosmetics, biosensors and detergents. Widening applications such as those in waste management and improved tanning techniques are other novel aspects of lipase utilization that are discussed in this review.

Bacteria↗
PubMed1976

Partial purification and characterization of a triglyceride lipase from pig adipose tissue.

A triglyceride lipase was extracted from defatted pig adipose tissue powder with dilute ammonia and purified about 230-fold by a combination of ammonium sulfate fractionation, heparin-Sepharose 4B, DEAE-cellulose, and Sephadex G-150 column chromatographies and isoelectrofocusing electrophoresis. The enzyme was distinguishable in physical and kinetic properties from the two previously defined lipases in adipose tissue, lipoprotein lipase, and hormone-sensitive lipase. The purified enzyme was fully active in the absence of serum lipoprotein and was not stimulated by adenosine 3':5'-monophosphate-dependent protein kinase. In marked contrast to the already defined lipases, the enzyme was strongly inhibited by serum albumin. The enzyme had a molecular weigt of about 43,000, a pI of 5.2, and pH optimum of 7.0. The enzyme hydrolyzed triolein to oleic acid and glycerol, and did not exhibit esterase activity. The apparent Km for triolein was 0.05 mM. Physiological roles of this new species of lipase remained to be explored.

Adipose Tissue↗
PubMed1999

Metabolic and genetic determinants of HDL metabolism and hepatic lipase activity in normolipidemic females.

The metabolic and genetic determinants of HDL cholesterol (HDL-C) levels and HDL turnover were studied in 36 normolipidemic female subjects on a whole-food low-fat metabolic diet. Lipid, lipoprotein, and apolipoprotein levels, lipoprotein size, and apolipoprotein turnover parameters were determined, as were genetic variation at one site in the hepatic lipase promoter and six sites in the apolipoprotein AI/CIII/AIV gene cluster. Menopause had no significant effect on HDL-C or turnover. Stepwise multiple regression analysis revealed that HDL-C was most strongly correlated with HDL size, apolipoprotein A-II (apoA-II), and apolipoprotein A-I (apoA-I) levels, which together could account for 90% of the variation in HDL-C. HDL size was inversely correlated with triglycerides, body mass index, and hepatic lipase activity, which together accounted for 82% of the variation in HDL size. The hepatic lipase promoter genotype had a strong effect on hepatic lipase activity and could account for 38% of the variation in hepatic lipase activity. The apoA-I transport rate (AI-TR) was the major determinant of apoA-I levels, but AI-TR was not associated with six common genetic polymorphism in the apoAI/CIII/AIV gene cluster.A simplified model of HDL metabolism is proposed, in which A-I and apoA-II levels combined with triglycerides, and hepatic lipase activity could account for 80% of the variation in HDL-C.

Adult↗
PubMed2000

Screening for lipase activity in the oil palm.

The oil palm mesocarp contains an endogenous lipase which is strongly activated at low temperature. Lipase activity is thus very conveniently assayed by prior exposure of the fruits to low temperature. More than 100 oil palm samples from the germplasm collection of the Palm Oil Research Institute of Malaysia (now known as the Malaysian Palm Oil Board) were screened for non-esterified fatty acid activity using both the low-temperature activation assay and a radioactivity assay. The results showed good correlation between assay procedures. The different samples had a very wide range of lipase activity. Elaeis oleifera samples had significantly lower lipase activity compared with E. guineensis (var. tenera) samples. Even within E. guineensis (var. tenera), there was a wide range of activity. The results confirmed that lipase activity is genotype-dependent. Selection for lipase genotypes is thus possible and this will have obvious commercial value.

Fatty Acids, Nonesterified↗
PubMed2001

[Studies on lipase production from Candida rugosa].

We studied some factors affecting the lipase production from candida rugosa, they mainly included medium compositions and culture condition. The result showed that the optimal medium compositions for lipase production are 0.1% glucose 4.0% olive oil (carbon source), 0.3% NH4NO3(nitrogen source), 1.2% K2HPO4 and 0.4% MgSO4.7H2O. And the optimal culture condition is initial pH6.5, temperature 30 degrees C, agitation 180 r/min and time 60 h. As a result, and the lipase activity could reach 19.5 u/mL. Meanwhile we found that the surfactant could be helpful to the lipase production, and the optimal surfactant concentration was 0.03% GPE. The lipase activity was improved by more than 170% after we optimized the medium compositions and culture condition. While in a 5L fermentator, the lipase activity of fermentation broth could reach 33.5 u/mL within 48 hours.

Candida↗
PubMed2002

Retinal pigment epithelial acid lipase activity and lipoprotein receptors: effects of dietary omega-3 fatty acids.

PURPOSE: To show that fish oil-derived omega-3 polyunsaturated fatty acids, delivered to the retinal pigment epithelium (RPE) by circulating low-density lipoproteins (LDL), enhance already considerable RPE lysosomal acid lipase activity, providing for more efficient hydrolysis of intralysosomal RPE lipids, an effect that may help prevent development of age-related macular degeneration (ARMD). METHODS: Colorimetric biochemical and histochemical techniques were used to demonstrate RPE acid lipase in situ, in vitro, and after challenge with phagocytic stimuli. Receptor-mediated RPE uptake of fluorescently labeled native, aceto-acetylated, and oxidized LDL was studied in vitro and in vivo. LDL effects on RPE lysosomal enzymes were assessed. Lysosomal enzyme activity was compared in RPE cells from monkeys fed diets rich in fish oil to those from control animals and in cultured RPE cells exposed to sera from these monkeys. RESULTS: RPE acid lipase activity was substantial and comparable to that of mononuclear phagocytes. Acid lipase activity increased significantly following phagocytic challenge with photoreceptor outer segment (POS) membranes. Receptor-mediated RPE uptake of labeled lipoproteins was determined in vitro. Distinctive uptake of labeled lipoproteins occurred in RPE cells and mononuclear phagocytes in vivo. Native LDL enhanced RPE lysosomal enzyme activity. RPE lysosomal enzymes increased significantly in RPE cells from monkeys fed fish oil-rich diets and in cultured RPE cells exposed to their sera. CONCLUSIONS: RPE cells contain substantial acid lipase for efficient metabolism of lipids imbibed by POS phagocytosis and LDL uptake. Diets rich in fish oil-derived omega-3 fatty acids, by enhancing acid lipase, may reduce RPE lipofuscin accumulation, RPE oxidative damage, and the development of ARMD.

Acyltransferases↗
PubMed1992

Staphylococcal lipase affects phagocytosis of Staphylococcus aureus by human granulocytes and monocytes.

The rate of immunological and non-immunological phagocytosis of staphylococci by lipase pre-treated human granulocytes and monocytes was compared. It was found that the effect of this enzyme on two types of cells is opposite. Lipase decreases phagocytosis by granulocytes and increases by monocytes. The revealed differences between phagocytosing cells studied prompted us to investigate the influence of lipase on Fc receptors on these cells (rosette EA test). The different susceptibility of Fc receptors on non-activated phagocytes to lipase was found. This could be at least partially responsible for the difference observed between phagocytic activity of granulocytes (decreased) and monocytes (increased) pretreated with staphylococcal lipase. Inactivated enzyme showed a similar effect as active enzyme in the case of granulocytes. However, inactivated enzyme had no effect on rosette formation by lipase pretreated monocytes, indicating an enzymatic effect.

Dose-Response Relationship, Immunologic↗
PubMed1992

Determination of pancreatic lipase by immunoactivation technology. A rapid test system with high sensitivity and specificity.

This paper describes the test characteristics and clinical relevance of a newly developed homogeneous enzyme immunoassay IMAC lipase test for the determination of serum pancreatic lipase. The method of determination is based on an immunoactivation technology and utilizes antibody fragments against human pancreatic lipase covalently bound to the marker enzyme horseradish peroxidase. The serum samples of 408 persons were investigated with this new assay. The within-run and day-to-day precision, the linearity, and the recovery of this immunoassay correspond to a very high degree to the requirements made of a modern immunological test. Comparison with an ELISA method resulted in a correlation coefficient of 0.971, whereby the IMAC lipase assay tended to register lower serum values. The serum range for the IMAC lipase test is 0-47 micrograms/L, based on a normal collective of 187 healthy controls. A sensitivity of 95.8% for the diagnosis of acute pancreatitis at a cutoff level of twice the upper normal range and a specificity of 99.3% at an efficiency of 99.8% can be given. The advantage of the IMAC lipase test method is its ability to be adapted to work on automatic laboratory analyzers.

Acute Disease↗
PubMed1992

Adipose cell size and distribution in familial lipoprotein lipase deficiency.

To determine the effect of lipoprotein lipase deficiency on the size distribution of fat cell populations in human adipose tissues, abdominal and femoral subcutaneous fat tissue biopsies were obtained from seven patients affected by familial hyperchylomicronaemia. These patients were characterized by massive accumulation of chylomicrons in the fasting state due to defective catabolism of plasma triglyceride-rich lipoproteins. They had no post-heparin plasma lipoprotein lipase activity and their fat tissues were deficient in lipoprotein lipase activity. The size distribution of adipocytes examined by scanning electron microscopy were similar to distributions observed in control subjects. Patient fat cell diameters were not statistically different from control fat cells obtained from subjects of similar body mass index. Mature fat cells contributed to 99% of the total fat tissue mass in lipoprotein lipase deficiency. Normal adiposity in lipoprotein lipase deficiency can thus be attributed to mature adipocytes and not to hyperplastic growth of immature fat cells. It is concluded that normal adipose tissue homeostasis is maintained in these patients in spite of the deficiency in lipoprotein lipase activity.

Adipose Tissue↗
PubMed1976

Effects of colipase and taurodeoxycholate on the catalytic and physical properties of pancreatic lipase B at an oil water interface.

A monolayer reaction system employing tripropionin and siliconized glass beads was used to study the effects of taurodeoxycholate and colipase on the catalytic activity, interfacial stability, and interfacial affinity of porcine pancreatic lipase B (EC 3.1.1.3) The stability and catalytic activity of lipase at the bead-water interface are governed by the same two ionizable groups with pKa values (in the absence of cofactors) of 5.6 and 9.3. Colipase alone or with bile salt caused only a slight perturbation of these values. At low concentrations, 0 to 0.3mM, taurodeoxycholate increases the stability of lipase by 5-fold. At higher concentrations, 0.3 to 0.8 mM, but still below its critical micelle concentration, taurodeoxycholate prevents the adsorption of lipase to the bead-water interface. This appears to be the major mechanism by which this bile salt inhibits lipolysis. Colipase exerts small positive effects on lipase stability and catalytic activity. More importantly, colipase enables the adsorption of lipase in the presence of bile salt, thereby reversing the inhibition.

Animals↗
PubMed1992

The catalytic site residues and interfacial binding of human pancreatic lipase.

In this study, the essential serine residue and 2 other amino acids in human pancreatic triglyceride lipase (triacylglycerol acylhydrolase, EC 3.1.1.3) were tested for their contribution to the enzyme's catalytic site or interfacial binding site. By site-specific mutagenesis of the cDNA for human pancreatic lipase, amino acid substitutions were made at Ser153, His264, and Asp177. The mutant cDNAs were expressed in transfected COS-1 cells. Both the medium and the cells were examined for the presence of pancreatic lipase by Western blot analysis. The activity of the expressed proteins against triolein and the interfacial binding was measured. Proteins with mutations in Ser153 were secreted by the cells and bound to interfaces but had no detectable activity. Changing His264 to a leucine or Asp177 to an asparagine also produced inactive lipase. Substituting glutamic acid for Asp177 produced an active protein. These results demonstrate that Ser153 is involved in the catalytic site of pancreatic lipase and is not crucial for interfacial binding. Moreover, the essential roles of His264 and Asp177 in catalysis were demonstrated. A Ser-His-Asp catalytic triad similar to that present in serine proteases is present in human pancreatic lipase.

Animals↗
PubMed1992

Electrophoretic fractionation of pancreatic lipase.

Human pancreatic isolipases were separated by electrophoresis on cellulose acetate membrane. Band visualization by fluorescence detection of NADH produced by beta-oxidation cyclic reaction of fatty acid liberated from 1,2-dilinoleoylglycerol by lipase was achieved by making a two-plate "sandwich" of an electrophoresis plate and a substrate-bearing plate. Two true lipase forms, named L1 and L2 to reflect their electrophoretic migration, were resolved with this method and quantified by densitometry. The procedure was not only simple and rapid but also precise (between-run CV less than 13.5%) and sensitive (detected lipase fractions of less than 2 U/L). L1 (mean 57% of total lipase, SD 19.3%) and L2 (mean 43%, SD 19.3%) lipase forms were found in all normal persons studied. In a preliminary clinical study of 27 emergency room patients, evaluation of the lipase electrophoretic pattern in serum did not separate patients with acute pancreatitis from those with other acute abdominal disorders.

Abdominal Pain↗
PubMed2005

Biochemical analysis of serum pancreatic amylase and lipase enzymes in patients with type 1 and type 2 diabetes mellitus.

OBJECTIVE: To examine the pancreatic exocrine insufficiency in patient with diabetes mellitus by estimating serum pancreatic amylase and lipase enzymes in healthy subjects and in type 1 and type 2 diabetic patients. METHODS: The study was conducted on 20 normal healthy volunteers and 39 diabetic patients referred to Al-Isra Medical Laboratory, Amman, Jordan during the period from April - November 2003 after recording their age and gender. The age of onset of diabetes and the type of treatment were determined and the patients were categorized into type 1 and type 2 diabetics. Blood samples were collected and analyzed for fasting blood sugar (FBS), glycosylated hemoglobin (HbA1C), serum insulin, and serum pancreatic amylase and lipase enzymes. All biochemical tests were carried out in the medical laboratories of Islamic Hospital, Amman, Jordan. All estimates were presented as means +/- SD, and statistical treatment of data were performed using student t-test. RESULTS: The FBS and HbA1C estimates were consistently higher in type 1 and type 2 diabetic patients, while no significant changes were observed in the estimates of serum insulin between the normal and diabetic patients. The reduction in serum pancreatic amylase was recorded in both types of diabetes, which amounted to 71% for type 1 diabetics and 49% for type 2 diabetics. On the other hand, reduction in serum lipase was only detected in type 1 diabetics amounting to 31%. Correlation of the reduction in serum amylase and lipase levels with the duration of disease revealed a remarkable decrease in both enzymes in patients with long-standing disease (76% and 39%) in type 1 diabetic patients. Whereas, patients with very low serum insulin estimates the reduction in serum amylase was 77% while serum lipase level was reduced by 42%. Similarly, the reduction in serum amylase in type 2 diabetes was higher in patients with longer duration of illness (59%) and in patients with low serum insulin value (79%), while reduction in serum lipase was only detected in patients with very low serum insulin (34%). No differences in all measured parameters between males and females were recorded in type 1 and type 2 diabetics. CONCLUSION: Although most of diabetic research has been focused on dyslipidemia as a major risk factor for cardiac, cerebral and renal complications, the present study clearly illustrates an impairment of pancreatic exocrine function in type 1 and type 2 diabetes. We suggest that analysis of serum pancreatic enzymes could be an additional informative parameter for the assessment of chronicity and progress of the illness as well as the response to therapy.

Adult↗
PubMedDate not supplied

Serum lipase assay. A test of choice in acute pancreatitis.

We evaluated the clinical accuracy of an automated turbidimetric assay for serum lipase determination in order to screen for acute pancreatic damage. Seventy patients with pancreatic and thirty with nonpancreatic digestive diseases were studied. Fifty-two healthy subjects were also studied as controls. Serum lipase concentrations were abnormally high in all patients with acute pancreatitis and in 3 (10%) in the group of 30 patients with nonpancreatic acute abdomen. In the 35 patients with chronic pancreatitis studied during clinical remission, serum lipase levels were abnormally high in 8 (23%), and abnormally low in 3 (9%). In the 9 patients with pancreatic cancer, 4 (44%) had abnormally elevated serum lipase values and 1 (11%) abnormally low. The results indicate that serum lipase determination is useful in the emergency diagnosis of acute pancreatic damage because of its high sensitivity and specificity. In patients with chronic pancreatitis and in patients with pancreatic carcinoma serum lipase determination is of limited value.

Acute Disease↗
PubMed2003

[Overexpression of Penicillium expansum lipase gene in Pichia pastoris].

The alkaline lipase gene of Penicillium expansum (PEL) was coloned into the yeast integrative plasmid pPIC3.5K, which was then transformed into His4 mutant yeast GS115. Recombinant Pichia strains were obtained by minimal olive oil-methanol plates screening and confirmed by PCR. The expression producus of PEL gene was analysis by SDS-PAGE and olive oil plate, the result indicated that PEL gene was functionally overexpressed in Pichia pastoris and up to 95% of the secreted protein. Recombinant lipase had a molecular mass of 28kD, showing a range similar to that of PEL, could hydrolyze olive oil and formed clear halos in the olive oil plates. Four different strategies (different media, pH, glycerol and methanol concentration) were applied to optimize the cultivation conditions, the activity of lipase was up to 260 u/mL under the optimal cultivation conditions. It is pointed out that the absence of the expensive biotin and yeast nitrogen base in the medium increased the lipase production. The possible reason of this result is absence of yeast nitrogen base increased the medium pH during cultivation, and PEL shows a higher stability at this condition. The lipase activity of the supernatant from the culture grown at pH 7 was higher than the one from the culture in the same medium at pH 6.0 is due to the pH stability of PEL too. The results also showed that the methanol and glycerol concentration had a marked effect on the production of lipase.

Enzyme Stability↗
PubMed1991

Diagnostic and prognostic utility of phospholipase A activity in patients with acute pancreatitis: comparison with amylase and lipase.

We compared the diagnostic and prognostic utility of phospholipase A (PLA; EC 3.1.1.4) for acute pancreatitis with that of amylase and lipase by analysis of sera from 151 consecutive patients presenting with abdominal pain in whom assays of serum amylase and (or) lipase had been ordered. We determined the diagnostic accuracy for both the initial and the peak enzyme activities. Maximal diagnostic accuracy obtained for the initial activities of amylase, lipase, and PLA was 0.83, 0.83, and 0.76 at cutoff values of 650, 650, and 41 U/L, respectively. Use of peak enzyme activities showed maximal diagnostic accuracy of 0.85, 0.86, and 0.73 at cutoff values of 650, 1050, and 42 U/L, respectively. Receiver-operator characteristic curve analysis revealed the diagnostic performance of amylase and lipase to be similar, whereas that of PLA was almost random and not incremental. As with amylase and lipase, PLA activities in sera showed no relation to patients' survival; three patients who died after an attack of acute pancreatitis failed to demonstrate the dramatic increases in PLA activity previously described. We conclude that assessing the severity of acute pancreatitis by using enzyme activities still remains problematical. Measurements of amylase or lipase activities provide similar diagnostic discrimination when appropriate cutoff values are used and remain the methods of choice for diagnosis of acute pancreatitis.

Acute Disease↗
PubMed2006

S5 Lipase: an organic solvent tolerant enzyme.

In this study, an organic solvent tolerant bacterial strain was isolated. This strain was identified as Pseudomonas sp. strain S5, and was shown to degrade BTEX (Benzene, Toluene, Ethyl-Benzene, and Xylene). Strain S5 generates an organic solvent-tolerant lipase in the late logarithmic phase of growth. Maximum lipase production was exhibited when peptone was utilized as the sole nitrogen source. Addition of any of the selected carbon sources to the medium resulted in a significant reduction of enzyme production. Lower lipase generation was noted when an inorganic nitrogen source was used as the sole nitrogen source. This bacterium hydrolyzed all tested triglycerides and the highest levels of production were observed when olive oil was used as a natural triglyceride. Basal medium containing Tween 60 enhanced lipase production to the most significant degree. The absence of magnesium ions (Mg2+) in the basal medium was also shown to stimulate lipase production. Meanwhile, an alkaline earth metal ion, Na+, was found to stimulate the production of S5 lipase.

Benzene↗