Positive association of the hepatic lipase gene polymorphism c.514C > T with estrogen replacement therapy response

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Pulchinelli Alvaro

2011-11-01

Full Text Available Abstract Background Hepatic lipase (HL, an enzyme present in the hepatic sinusoids, is responsible for the lipolysis of lipoproteins. Human HL contains four polymorphic sites: G-250A, T-710C, A-763G, and C-514T single-nucleotide polymorphism (SNPs. The last polymorphism is the focus of the current study. The genotypes associated with the C-514T polymorphism are CC (normal homozygous - W, CT (heterozygous - H, and TT (minor-allele homozygous - M. HL activity is significantly impaired in individuals of the TT and CT genotypes. A total of 58 post-menopausal women were studied. The subjects were hysterectomized women receiving hormone replacement therapy consisting of 0.625 mg of conjugated equine estrogen once a day. The inclusion criteria were menopause of up to three years and normal blood tests, radiographs, cervical-vaginal cytology, and densitometry. DNA was extracted from the buccal and blood cells of all 58 patients using a commercially available kit (GFX® - Amersham-Pharmacia, USA. Results Statistically significant reductions in triglycerides (t = 2.16; n = 58; p = 0.03 but not in total cholesterol (t = 0.14; n = 58; p = 0.89 were found after treatment. This group of good responders were carriers of the T allele; the CT and TT genotypes were present significantly more frequently than in the group of non-responders (p = 0.02 or p = 0.07, respectively. However, no significant difference in HDL-C (t = 0.94; n = 58; p = 0.35 or LDL-C (t = -0.83; n = 58; p = 0.41 was found in these patients. Conclusions The variation in lipid profile associated with the C-514T polymorphism is significant, and the T allele is associated with the best response to ERT.

Proteinuria and lipoprotein lipase activity in Miniature Schnauzer dogs with and without hypertriglyceridemia.

Science.gov (United States)

Furrow, E; Jaeger, J Q; Parker, V J; Hinchcliff, K W; Johnson, S E; Murdoch, S J; de Boer, I H; Sherding, R G; Brunzell, J D

2016-06-01

Spontaneous hyperlipidemia in rats causes glomerular disease. Idiopathic hypertriglyceridemia (HTG) is prevalent in Miniature Schnauzers, but its relationship with proteinuria is unknown. Decreased activity of major lipid metabolism enzymes, lipoprotein lipase (LPL) and hepatic lipase (HL), may play a role in the cyclic relationship between hyperlipidemia and proteinuria. These enzymes have also not been previously investigated in Miniature Schnauzers. The aims of this study were to determine the relationship between HTG and proteinuria in Miniature Schnauzers and to measure LPL and HL activities in a subset of dogs. Fifty-seven Miniature Schnauzers were recruited (34 with and 23 without HTG). Fasting serum triglyceride concentrations and urine protein-to-creatinine ratios (UPC) were measured in all dogs, and LPL and HL activities were determined in 17 dogs (8 with and 9 without HTG). There was a strong positive correlation between triglyceride concentration and UPC (r = 0.77-0.83, P Schnauzers and could be due to lipid-induced glomerular injury. Reduced LPL activity may contribute to the severity of HTG, but further assay validation is required. Copyright © 2016 Elsevier Ltd. All rights reserved.

Atherogenic Lipoproteins in Subclinical Hypothyroidism and Their Relationship with Hepatic Lipase Activity: Response to Replacement Treatment with Levothyroxine.

Science.gov (United States)

Brenta, Gabriela; Berg, Gabriela; Miksztowicz, Veronica; Lopez, Graciela; Lucero, Diego; Faingold, Cristina; Murakami, Masami; Machima, Tetsudo; Nakajima, Katsuyuki; Schreier, Laura

2016-03-01

Qualitative lipoprotein changes, such as an increase in fasting remnants, are reported in subclinical hypothyroidism (SCH). It was hypothesized that such changes are due to reduced hepatic lipase (HL) activity in SCH: HL is an enzyme regulated by thyroid hormones, and is involved in the degradation of triglyceride (TG)-rich remnants. This study aimed to quantify remnant-like lipoproteins (RLP), small dense LDL (sdLDL), and HL activity in women with SCH, and to assess these parameters after levothyroxine replacement therapy. This was an observational cross-sectional study with a subsequent longitudinal follow-up. Findings in women with thyrotropin levels >4.5 mIU/L (SH group) were compared with age- and body mass index (BMI)-matched euthyroid women (control group). In addition, a subgroup analysis was undertaken in SCH women who chose to receive levothyroxine treatment (0.9 μg/kg/day) for 6 months. RLP was quantified by measuring cholesterol (RLP-C) and triglycerides (RLP-TG) after immunoaffinity chromatography, and sdLDL by automated standardized methods; HL activity was measured in post-heparin plasma. The SCH group included 37 women; 29 women were included in the control group. In addition, 22 women with SCH were included in the subgroup analysis (levothyroxine treatment). Significantly higher RLP values were observed in the SCH group than in the control group: RLP-C (median [range], mg/dL): 20.3 (5.8-66.8) versus 10.2 (2.7-36.3), p = 0.005; RLP-TG (mg/dL): 26.3 (3.2-123.3) versus 12.1 (2.5-61.6), p = 0.033. HL activity (mean ± standard deviation [SD], μmol free fatty acid/mL post-heparin plasma.h)-9.83 ± 4.25 versus 9.92 ± 5.20, p = 0.707-and sdLDL levels (mg/dL)-23.1 ± 10.7 versus 22.6 ± 8.4, p = 0.83-were similar. After levothyroxine, RLP-C decreased-21.5 (5.8-66.8) versus 17.2 (4.1-45.6), p = 0.023-and HL increased-9.75 ± 4.04 versus 11.86 ± 4.58, p = 0.012-in the subgroup of SCH women. No changes

Rhein triggers apoptosis via induction of endoplasmic reticulum stress, caspase-4 and intracellular calcium in primary human hepatic HL-7702 cells

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KoraMagazi, Arouna [Department of Clinical Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu (China); Wang, Dandan [Department of Pharmacology, China Pharmaceutical University, Nanjing, Jiangsu (China); Yousef, Bashir; Guerram, Mounia [Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu (China); Yu, Feng, E-mail: yufengcpu14@yahoo.com [Department of Clinical Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu (China); Department of Pharmacology, China Pharmaceutical University, Nanjing, Jiangsu (China); Key Laboratory of Drug Quality Control and Pharmacovigilance, China Pharmaceutical University, Nanjing, Jiangsu (China)

2016-04-22

Rhein is an active component of rhubarb; a traditional Chinese medicine reported to induce apoptosis and cause liver toxicity. However, rhein's apoptotic-inducing effects, as well as its molecular mechanisms of action on hepatic cells need to be further explored. In the present study, rhein was found to trigger apoptosis in primary human hepatic HL-7702 cells as showed by annexin V/PI double staining assay and nuclear morphological changes demonstrated by Hoechst 33258 staining. Moreover, it was observed that the mechanism implicated in rhein-induced apoptosis was caspase-dependent, presumably via ER-stress associated pathways, as illustrated by up-regulation of glucose-regulated protein 78 (GRP 78), PKR-like ER kinase (PERK), C-Jun N-terminal kinase (JNK) and CCAAT/enhancer-binding protein homologous protein (CHOP). Meanwhile, caspase-4 as a hallmark of ER-stress, was also showed to be activated following by caspase-3 activation. Furthermore, rhein also promoted intracellular elevation of calcium that contributed in apoptosis induction. Interestingly, pre-treatment with calpain inhibitor I reduced the effects of rhein on apoptosis induction and JNK activation. These data suggested that rhein-induced apoptosis through ER-stress and elevated intracellular calcium level in HL-7702 cells. - Highlights: • Rhein triggers apoptotic cell death on primary human hepatic HL-7702 cells. • Rhein leads to caspase-4 activation in HL-7702 cells. • Rhein induces endoplasmic reticulum stress pathways in HL-7702 cells. • Rhein causes elevation of intracellular calcium concentrations in HL-7702 cells.

Diagnostic value of post-heparin lipase testing in detecting common genetic variants in the LPL and LIPC genes

NARCIS (Netherlands)

van Hoek, Mandy; Dallinga-Thie, Geesje M.; Steyerberg, Ewout W.; Sijbrands, Eric J. G.

2009-01-01

Post-heparin lipoprotein lipase and hepatic lipase activities are used to identify primary disorders of triglyceride and HDL-cholesterol metabolism. Their ability to identify common variants in the lipoprotein lipase (LPL) and hepatic lipase (LIPC) genes is unclear. To investigate the ability of

Endothelial lipase is a major determinant of HDL level

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Ishida, Tatsuro; Choi, Sungshin; Kundu, Ramendra K.; Hirata, Ken-Ichi; Rubin, Edward M.; Cooper, Allen D.; Quertermous, Thomas

2003-01-30

For the past three decades, epidemiologic studies have consistently demonstrated an inverse relationship between plasma HDL cholesterol (HDL-C) concentrations and coronary heart disease (CHD). Population-based studies have provided compelling evidence that low HDL-C levels are a risk factor for CHD, and several clinical interventions that increased plasma levels of HDL-C were associated with a reduction in CHD risk. These findings have stimulated extensive investigation into the determinants of plasma HDL-C levels. Turnover studies using radiolabeled apolipoprotein A-I, the major protein component of HDL, suggest that plasma HDL-C concentrations are highly correlated with the rate of clearance of apolipoprotein AI. However, the metabolic mechanisms by which HDL are catabolized have not been fully defined. Previous studies in humans with genetic deficiency of cholesteryl ester transfer protein, and in mice lacking the scavenger receptor BI (SR-BI), have demonstrated that these proteins participate in the removal of cholesterol from HDL, while observations in individuals with mutations in hepatic lipase indicate that this enzyme hydrolyzes HDL triglycerides. In this issue of the JCI, reports from laboratories of Tom Quertermous and Dan Rader now indicate that endothelial lipase (LIPG), a newly identified member of the lipase family, catalyzes the hydrolysis of HDL phospholipids and facilitates the clearance of HDL from the circulation. Endothelial lipase was initially cloned by both of these laboratories using entirely different strategies. Quertermous and his colleagues identified endothelial lipase as a transcript that was upregulated in cultured human umbilical vein endothelial cells undergoing tube formation, whereas the Rader group cloned endothelial lipase as a transcript that was upregulated in the human macrophage-like cell line THP-1 exposed to oxidized LDL. Database searches revealed that endothelial lipase shows strong sequence similarity to lipoprotein

Increased Hepatic Expression of Endothelial Lipase Inhibits Cholesterol Diet-Induced Hypercholesterolemia and Atherosclerosis in Transgenic Rabbits.

Science.gov (United States)

Wang, Chuan; Nishijima, Kazutoshi; Kitajima, Shuji; Niimi, Manabu; Yan, Haizhao; Chen, Yajie; Ning, Bo; Matsuhisa, Fumikazu; Liu, Enqi; Zhang, Jifeng; Chen, Y Eugene; Fan, Jianglin

2017-07-01

Endothelial lipase (EL) is a key determinant in plasma high-density lipoprotein-cholesterol. However, functional roles of EL on the development of atherosclerosis have not been clarified. We investigated whether hepatic expression of EL affects plasma lipoprotein metabolism and cholesterol diet-induced atherosclerosis. We generated transgenic (Tg) rabbits expressing the human EL gene in the liver and then examined the effects of EL expression on plasma lipids and lipoproteins and compared the susceptibility of Tg rabbits with cholesterol diet-induced atherosclerosis with non-Tg littermates. On a chow diet, hepatic expression of human EL in Tg rabbits led to remarkable reductions in plasma levels of total cholesterol, phospholipids, and high-density lipoprotein-cholesterol compared with non-Tg controls. On a cholesterol-rich diet for 16 weeks, Tg rabbits exhibited significantly lower hypercholesterolemia and less atherosclerosis than non-Tg littermates. In Tg rabbits, gross lesion area of aortic atherosclerosis was reduced by 52%, and the lesions were characterized by fewer macrophages and smooth muscle cells compared with non-Tg littermates. Increased hepatic expression of EL attenuates cholesterol diet-induced hypercholesterolemia and protects against atherosclerosis. © 2017 American Heart Association, Inc.

PLTP activity in premenopausal women. Relationship with lipoprotein lipase, HDL, LDL, body fat, and insulin resistance.

Science.gov (United States)

Murdoch, S J; Carr, M C; Hokanson, J E; Brunzell, J D; Albers, J J

2000-02-01

Plasma phospholipid transfer protein (PLTP) is thought to play a major role in the facilitated transfer of phospholipids between lipoproteins and in the modulation of high density lipoprotein (HDL) particle size and composition. However, little has been reported concerning the relationships of PLTP with plasma lipoprotein parameters, lipolytic enzymes, body fat distribution, insulin, and glucose in normolipidemic individuals, particularly females. In the present study, 50 normolipidemic healthy premenopausal females were investigated. The relationships between the plasma PLTP activity and selected variables were assessed. PLTP activity was significantly and positively correlated with low density lipoprotein (LDL) cholesterol (r(s) = 0.53), apoB (r(s) = 0.44), glucose (r(s) = 0.40), HDL cholesterol (r(s) = 0.38), HDL(3) cholesterol (r(s) = 0.37), lipoprotein lipase activity (r(s) = 0.36), insulin (r(s) = 0.33), subcutaneous abdominal fat (r(s) = 0.36), intra-abdominal fat (r(s) = 0.29), and body mass index (r(s) = 0.29). HDL(2) cholesterol, triglyceride, and hepatic lipase were not significantly related to PLTP activity. As HDL(2) can be decreased by hepatic lipase and hepatic lipase is increased in obesity with increasing intra-abdominal fat, the participants were divided into sub-groups of non-obese (n = 35) and obese (n = 15) individuals and the correlation of PLTP with HDL(2) cholesterol was re-examined. In the non-obese subjects, HDL(2) cholesterol was found to be significantly and positively related to PLTP activity (r(s) = 0.44). Adjustment of the HDL(2) values for the effect of hepatic lipase activity resulted in a significant positive correlation between PLTP and HDL(2) (r(s) = 0.41), indicating that the strength of the relationship between PLTP activity and HDL(2) can be reduced by the opposing effect of hepatic lipase on HDL(2) concentrations. We conclude that PLTP-facilitated lipid transfer activity is related to HDL and LDL metabolism, as well as

Insulin Clearance Is Associated with Hepatic Lipase Activity and Lipid and Adiposity Traits in Mexican Americans.

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Artak Labadzhyan

Full Text Available Reduction in insulin clearance plays an important role in the compensatory response to insulin resistance. Given the importance of this trait to the pathogenesis of diabetes, a deeper understanding of its regulation is warranted. Our goal was to identify metabolic and cardiovascular traits that are independently associated with metabolic clearance rate of insulin (MCRI. We conducted a cross-sectional analysis of metabolic and cardiovascular traits in 765 participants from the Mexican-American Coronary Artery Disease (MACAD project who had undergone blood sampling, oral glucose tolerance test, euglycemic-hyperinsulinemic clamp, dual-energy X-ray absorptiometry, and carotid ultrasound. We assessed correlations of MCRI with traits from seven domains, including anthropometry, biomarkers, cardiovascular, glucose homeostasis, lipase activity, lipid profile, and liver function tests. We found inverse independent correlations between MCRI and hepatic lipase (P = 0.0004, insulin secretion (P = 0.0002, alanine aminotransferase (P = 0.0045, total fat mass (P = 0.014, and diabetes (P = 0.03. MCRI and apolipoprotein A-I exhibited a positive independent correlation (P = 0.035. These results generate a hypothesis that lipid and adiposity associated traits related to liver function may play a role in insulin clearance.

Human Placenta Extract Therapy for Feline Hepatic Lipidosis

OpenAIRE

2018-01-01

Feline hepatic lipidosis (HL), the most common hepatobiliary disease in cats, is characterized by the accumulation of excessive triglycerides (TGs) in more than 80% of hepatocytes. Forced oral feeding is recommended as the only therapy for this disease but the prognosis is often poor. As human placenta extract (Laennec) has been used to improve hepatic metabolism, we investigated the efficacy of this drug for the treatment of cats with HL. Ten cats diagnosed with HL in this study were treated...

Effects of Polyelectrolyte Complex Micelles and Their Components on the Enzymatic Activity of Lipase

NARCIS (Netherlands)

Lindhoud, Saskia; Norde, Willem; Cohen Stuart, Martinus Abraham

2010-01-01

The enzymatic activity of Hl-lipase embedded in complexes of poly-2-methylvinylpyridinium-co-poly(ethylene oxide) (P2MVP41−PEO205) and poly(acrylic acid)(PAA139) is studied as a function of the PAA139 + P2MVP41−PEO205 complex composition. The measurements revealed that there are several factors that

Hepatic Encephalopathy

Medline Plus

Full Text Available ... Lipase Deficiency Liver Cancer Liver Cysts Non-Alcoholic Fatty Liver Disease Primary Biliary Cholangitis Primary Sclerosing Cholangitis What ... B & C Alcohol-related Liver Disease Non-alcoholic Fatty Liver Disease (NAFLD) & Non-alcoholic Steatohepatitis (NASH) Autoimmune Hepatitis ...

New botanical drug, HL tablet, reduces hepatic fat as measured by magnetic resonance spectroscopy in patients with nonalcoholic fatty liver disease: A placebo-controlled, randomized, phase II trial.

Science.gov (United States)

Jeong, Jae Yoon; Sohn, Joo Hyun; Baek, Yang Hyun; Cho, Yong Kyun; Kim, Yongsoo; Kim, Hyeonjin

2017-08-28

To evaluate the efficacy and safety of HL tablet extracted from magnolia officinalis for treating patients with nonalcoholic fatty liver disease (NAFLD). Seventy-four patients with NAFLD diagnosed by ultrasonography were randomly assigned to 3 groups given high dose (400 mg) HL tablet, low dose (133.4 mg) HL tablet and placebo, respectively, daily for 12 wk. The primary endpoint was post-treatment change of hepatic fat content (HFC) measured by magnetic resonance spectroscopy. Secondary endpoints included changes of serum aspartate aminotransferase, alanine aminotransferase (ALT), cholesterol, triglyceride, free fatty acid, homeostasis model assessment-estimated insulin resistance, and body mass index (BMI). The mean HFC of the high dose HL group, but not of the low dose group, declined significantly after 12 wk of treatment (high dose vs placebo, P = 0.033; low dose vs placebo, P = 0.386). The mean changes of HFC from baseline at week 12 were -1.7% ± 3.1% in the high dose group ( P = 0.018), -1.21% ± 4.97% in the low dose group ( P = 0.254) and 0.61% ± 3.87% in the placebo group (relative changes compared to baseline, high dose were: -12.1% ± 23.5%, low dose: -3.2% ± 32.0%, and placebo: 7.6% ± 44.0%). Serum ALT levels also tended to decrease in the groups receiving HL tablet while other factors were unaffected. There were no moderate or severe treatment-related safety issues during the study. HL tablet is effective in reducing HFC without any negative lipid profiles, BMI changes and adverse effects.

Serum free amino acid concentration in hepatic lipidosis of dairy cows in the periparturient period.

Science.gov (United States)

Shibano, Ken-ichi; Kawamura, Seiichi

2006-04-01

Blood samples were taken from eight multiparous cows at a dairy farm on eight occasions between the prepartum period and peak lactation to study the serum concentrations of amino acids and biochemical constituents. The cows were classified as having either severe hepatic lipidosis (HL) or non-hepatic lipidosis (non-HL) according to their clinical condition after calving and changes in serum biochemical parameters. The serum concentrations of beta-hydroxybutyric acid were higher in the HL group than in the non-HL group (ANOVA: phepatic lipidosis.

Haemodynamic changes in hepatocellular carcinoma and liver parenchyma under balloon occlusion of the hepatic artery

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Sugihara, Fumie; Murata, Satoru; Ueda, Tatsuo; Yasui, Daisuke; Yamaguchi, Hidenori; Miki, Izumi; Kumita, Shin-ichiro [Nippon Medical School, Department of Radiology, Center for Advanced Medical Technology, Tokyo (Japan); Kawamoto, Chiaki [Nippon Medical School, Department of Internal Medicine, Tokyo (Japan); Uchida, Eiji [Nippon Medical School, Department of Surgery, Tokyo (Japan)

2017-06-15

To investigate haemodynamic changes in hepatocellular carcinoma (HCC) and liver under hepatic artery occlusion. Thirty-eight HCC nodules in 25 patients were included. Computed tomography (CT) during hepatic arteriography (CTHA) with and without balloon occlusion of the hepatic artery was performed. CT attenuation and enhancement volume of HCC and liver with and without balloon occlusion were measured on CTHA. Influence of balloon position (segmental or subsegmental branch) was evaluated based on differences in HCC-to-liver attenuation ratio (H/L ratio) and enhancement volume of HCC and liver. In the segmental group (n = 20), H/L ratio and enhancement volume of HCC and liver were significantly lower with balloon occlusion than without balloon occlusion. However, in the subsegmental group (n = 18), H/L ratio was significantly higher and liver enhancement volume was significantly lower with balloon occlusion; HCC enhancement volume was similar with and without balloon occlusion. Rate of change in H/L ratio and enhancement volume of HCC and liver were lower in the segmental group than in the subsegmental group. There were significantly more perfusion defects in HCC in the segmental group. Hepatic artery occlusion causes haemodynamic changes in HCC and liver, especially with segmental occlusion. (orig.)

Urinary orotic acid-to-creatinine ratios in cats with hepatic lipidosis.

Science.gov (United States)

VanSteenhouse, J L; Dimski, D S; Swenson, D H; Taboada, J

1999-06-01

To determine urinary orotic acid (OA) concentration and evaluate the urinary OA-to-creatinine ratio (OACR) in cats with hepatic lipidosis (HL). 20 cats with HL and 20 clinically normal cats. Hepatic lipidosis was diagnosed on the basis of clinical signs, results of serum biochemical analyses, exclusion of other concurrent illness, and cytologic or histologic evaluation of liver biopsy specimens. Urine samples were collected from each cat and frozen at -20 C until assayed. Urine creatinine concentrations were determined, using an alkaline picrate method followed by spectrophotometric assay. Urine OA concentration was determined, using high-performance liquid chromatography. Minimum amount of detectable OA in feline urine was 1 microg/ml. Because of small interfering peaks near the base of the OA peak, the minimum quantifiable concentration of OA was determined to be 5 microg/ml. Urinary OACR was compared in both groups of cats. Differences in urinary OACR were not detected between clinically normal cats and cats with HL. Peaks were not detected for urinary OA in any of the 20 clinically normal cats. Of the 20 HL cats, 14 did not have detectable peaks for urinary OA. Of the 6 HL cats that had detectable urinary OA peaks, 3 had values of <5 microg/ml. Apparently, OACR does not increase significantly in cats with HL. Urinary OACR is not a useful diagnostic test for HL in cats.

Experiements with an inactivated hepatitis leptospirosis vaccine in vaccination programmes for dogs.

Science.gov (United States)

Wilson, J H; Hermann-Dekkers, W M; Leemans-Dessy, S; Meijer, J W

1977-06-25

A fluid adjuvanted vaccine consisting of inactivated hepatitis virus (iH) and leptospirae antigens (L) was developed. The vaccine (Kavak iHL; Duphar) was tested in several vaccination programmes both alone and in combination with freeze dried measles (M) or distemper (D) vaccines. The results demonstrate that this new vaccine is also effective in pups with maternally derived antibodies, although a second vaccination at 14 weeks of age is recommended to boost the first vaccination. For the booster vaccination either the iHL-vaccine or the liver attenuated hepatitis vaccine (H) can be used.

Hepatic lipidosis in a black-headed python (Aspidites melanocephalus).

Science.gov (United States)

Simpson, Mark

2006-09-01

The number of people keeping reptiles in captivity has markedly increased, and widespread inappropriate husbandry will result in an increasing incidence of the diagnosis of hepatic lipidosis(HL). It may become apparent that some species of snake have predisposition to develop HL. In the specific instance of the genus Aspidites, alterations to the usual husbandry that limit feeding and thereby body weight should markedly lessen the chance of the animal's developing HL. It is important for clinicians to develop a more aggressive approach to these cases and to build a bank of data with which to promote understanding of this common malady.

Evaluation of cellulose-binding domain fused to a lipase for the lipase immobilization.

Science.gov (United States)

Hwang, Sangpill; Ahn, Jungoh; Lee, Sumin; Lee, Tai Gyu; Haam, Seungjoo; Lee, Kangtaek; Ahn, Ik-Sung; Jung, Joon-Ki

2004-04-01

A cellulose-binding domain (CBD) fragment of a cellulase gene of Trichoderma hazianum was fused to a lipase gene of Bacillus stearothermophilus L1 to make a gene cluster for CBD-BSL lipase. The specific activity of CBD-BSL lipase for oil hydrolysis increased by 33% after being immobilized on Avicel (microcrystalline cellulose), whereas those of CBD-BSL lipase and BSL lipase decreased by 16% and 54%, respectively, after being immobilized on silica gel. Although the loss of activity of an enzyme immobilized by adsorption has been reported previously, the loss of activity of the CBD-BSL lipase immobilized on Avicel was less than 3% after 12 h due to the irreversible binding of CBD to Avicel.

Hodgkin's lymphoma coexisting with liver failure secondary to acute on chronic hepatitis B.

Science.gov (United States)

Palta, Renee; McClune, Amy; Esrason, Karl

2013-04-16

Acute on chronic liver failure (ACLF) is rarely the initial manifestation of a malignant process or precipitated by the initiation of anti-viral treatment with a nucleoside or nucleotide agent. We report an unusual case of ACLF temporally associated with initiation of Entecavir for treatment of chronic hepatitis B. Early Hodgkin's lymphoma (HL) was unmasked with initiation of the anti-viral treatment which may have exacerbated ACLF. To the best of our knowledge, this has not been described in the literature. In reviewing our patients clinical course and liver autopsy, he developed a severe acute exacerbation of his chronic hepatitis B virus coinciding with the institution of antiviral therapy and the underlying HL perhaps modulating the overall degree of hepatic injury.

Bacterial lipases

NARCIS (Netherlands)

Jaeger, Karl-Erich; Ransac, Stéphane; Dijkstra, Bauke W.; Colson, Charles; Heuvel, Margreet van; Misset, Onno

Many different bacterial species produce lipases which hydrolyze esters of glycerol with preferably long-chain fatty acids. They act at the interface generated by a hydrophobic lipid substrate in a hydrophilic aqueous medium. A characteristic property of lipases is called interfacial activation,

Bacterial lipases for biotechnological applications

NARCIS (Netherlands)

Jaeger, Karl-Erich; Schneidinger, Bernd; Rosenau, Frank; Werner, Michael; Lang, Dietmar; Dijkstra, Bauke W.; Schimossek, Klaus; Zonta, Albin; Reetz, Manfred T.

1997-01-01

Lipase genes originating from the Gram-negative bacteria Serrutiu marcescens and Pseudomonus urruginosa were cloned. S. marcescens lipase was overexpressed in Escherichia coli yielding inclusion bodies which were purified and finally refolded to give enzymatically active lipase. The lipase operon of

Hodgkin’s lymphoma coexisting with liver failure secondary to acute on chronic hepatitis B

Science.gov (United States)

Palta, Renee; McClune, Amy; Esrason, Karl

2013-01-01

Acute on chronic liver failure (ACLF) is rarely the initial manifestation of a malignant process or precipitated by the initiation of anti-viral treatment with a nucleoside or nucleotide agent. We report an unusual case of ACLF temporally associated with initiation of Entecavir for treatment of chronic hepatitis B. Early Hodgkin’s lymphoma (HL) was unmasked with initiation of the anti-viral treatment which may have exacerbated ACLF. To the best of our knowledge, this has not been described in the literature. In reviewing our patients clinical course and liver autopsy, he developed a severe acute exacerbation of his chronic hepatitis B virus coinciding with the institution of antiviral therapy and the underlying HL perhaps modulating the overall degree of hepatic injury. PMID:24303460

A study of trans-rectal portal scintigraphy for the diagnostic evaluation of portal hypertension with hepatic cirrhosis

International Nuclear Information System (INIS)

Tang Mingdeng; Dong Weiyu; Liu Yonghua; He Pinyu; Li Zhener

1996-01-01

The portal hypertension of hepatic cirrhosis was studied by 99m Tc-MIBI trans-rectum imaging. The portal systemic circulation was evaluated by the heart-liver ratio (H/L ratio) and the portosystemic shunt index (SI). The H/L and SI in 12 normal cases were 0.145 +- 0.042 and 0.124 +- 0.029. Whereas in 18 patients with hepatobiliary diseases of non-cirrhosis were 0.207 +- 0.076 and 0.169 +- 0.051, and in 47 patients with hepatic cirrhosis were 0.751 +-0.313 and 0.422 +- 0.075. The results showed significant difference (P<0.01) between normal controls and non-cirrhosis group, and significant difference (P<0.001) between hepatic cirrhosis group and normal controls, non-cirrhosis group. A significant difference (P<0.05) in child-pugh's classification A, B and C groups was also found. A significant correlation (r = 0.95, P<0.01) with the H/L, SI and portal pressure measurement during operation was found. If H/L≥0.30, and SI≥0.22 were taken as positive criteria for diagnosis of portal hypertension with hepatic cirrhosis, the sensitivity, specificity and accuracy were 96%, 90% and 94% respectively. Therefore, it was a new method for the diagnosis of portal hypertension with hepatic cirrhosis

Hans Pöhl - Estlandssvenskarnas hövding = Hans Pöhl - rannarootslaste eestvõitleja / Torkel Jansson

Index Scriptorium Estoniae

Jansson, Torkel, 1947-

2011-01-01

Raamatututvustus: Hans Pöhl - Estlandssvenskarnas hövding : en biografi över Hans Pöhl (1876-1930), estlandssvenskarnas främste företrädare och ledare = Hans Pöhl - rannarootslaste eestvõitleja : Hans Pöhli (1876-1930), Eesti rootslaste vaimse liidri ja valgustaja elulugu. (Stockholm ; Tallinn, 2010)

Effects of stocking density on lipid deposition and expression of lipid-related genes in Amur sturgeon (Acipenser schrenckii).

Science.gov (United States)

Ren, Yuanyuan; Wen, Haishen; Li, Yun; Li, Jifang; He, Feng; Ni, Meng

2017-12-01

To investigate the correlation between lipid deposition variation and stocking density in Amur sturgeon (Acipenser schrenckii) and the possible physiological mechanism, fish were conducted in different stocking densities (LSD 5.5 kg/m 3 , MSD 8.0 kg/m 3 , and HSD 11.0 kg/m 3 ) for 70 days and then the growth index, lipid content, lipase activities, and the mRNA expressions of lipid-related genes were examined. Results showed that fish subjected to higher stocking density presented lower final body weights (FBW), specific growth ratio (SGR), and gonad adipose tissue index (GAI) (P density lipoprotein cholesterol (HDL-C) decreased significantly with increasing stocking density, while no significant change was observed for low-density lipoprotein cholesterol (LDL-C). Furthermore, the cDNAs encoding lipoprotein lipase (LPL) and hepatic lipase (HL) were isolated in Amur sturgeon, respectively. The full-length LPL cDNA was composed of 1757 bp with an open reading frame of 501 amino acids, while the complete nucleotide sequences of HL covered 1747 bp encoding 499 amino acids. In the liver, the activities and mRNA levels of LPL were markedly lower in HSD group, which were consistent with the variation tendency of HL. Fish reared in HSD group also presented lower levels of activities and mRNA expression of LPL in the muscle and gonad. Moreover, the expressions of peroxisome proliferator-activated receptor α (PPARα) in both the liver and skeletal muscle were significantly upregulated in HSD group. Overall, the results indicated that high stocking density negatively affects growth performance and lipid deposition of Amur sturgeon to a certain extent. The downregulation of LPL and HL and the upregulation of PPARα may be responsible for the lower lipid distribution of Amur sturgeon in higher stocking density.

A new transgenic rat model of hepatic steatosis and the metabolic syndrome

Czech Academy of Sciences Publication Activity Database

Qi, N.R.; Wang, J.; Zídek, Václav; Landa, Vladimír; Mlejnek, Petr; Kazdová, L.; Pravenec, Michal; Kurtz, T. W.

2005-01-01

Roč. 45, č. 5 (2005), s. 1004-1011 ISSN 0194-911X R&D Projects: GA MZd(CZ) NB7403; GA MŠk(CZ) 1M0520 Grant - others:NIH(US) HL35018; NIH(US) HL63709; NIH(US) TW01236 Institutional research plan: CEZ:AV0Z50110509 Keywords : hepatic steatosis * Srebp1a * transgenic SHR Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 6.331, year: 2005

Acid Lipase Disease

Science.gov (United States)

... of Neurological Disorders and Stroke conducts and supports research to understand lipid storage diseases such as acid lipase deficiency and ... of Neurological Disorders and Stroke conducts and supports research to understand lipid storage diseases such as acid lipase deficiency and ...

Lipoprotein lipase activity and mass, apolipoprotein C-II mass and polymorphisms of apolipoproteins E and A5 in subjects with prior acute hypertriglyceridaemic pancreatitis

Directory of Open Access Journals (Sweden)

García-Arias Carlota

2009-06-01

Full Text Available Abstract Background Severe hypertriglyceridaemia due to chylomicronemia may trigger an acute pancreatitis. However, the basic underlying mechanism is usually not well understood. We decided to analyze some proteins involved in the catabolism of triglyceride-rich lipoproteins in patients with severe hypertriglyceridaemia. Methods Twenty-four survivors of acute hypertriglyceridaemic pancreatitis (cases and 31 patients with severe hypertriglyceridaemia (controls were included. Clinical and anthropometrical data, chylomicronaemia, lipoprotein profile, postheparin lipoprotein lipase mass and activity, hepatic lipase activity, apolipoprotein C II and CIII mass, apo E and A5 polymorphisms were assessed. Results Only five cases were found to have LPL mass and activity deficiency, all of them thin and having the first episode in childhood. No cases had apolipoprotein CII deficiency. No significant differences were found between the non-deficient LPL cases and the controls in terms of obesity, diabetes, alcohol consumption, drug therapy, gender distribution, evidence of fasting chylomicronaemia, lipid levels, LPL activity and mass, hepatic lipase activity, CII and CIII mass or apo E polymorphisms. However, the SNP S19W of apo A5 tended to be more prevalent in cases than controls (40% vs. 23%, NS. Conclusion Primary defects in LPL and C-II are rare in survivors of acute hypertriglyceridaemic pancreatitis; lipase activity measurements should be restricted to those having their first episode during chilhood.

Lipoprotein lipase activity and mass, apolipoprotein C-II mass and polymorphisms of apolipoproteins E and A5 in subjects with prior acute hypertriglyceridaemic pancreatitis

Science.gov (United States)

2009-01-01

Background Severe hypertriglyceridaemia due to chylomicronemia may trigger an acute pancreatitis. However, the basic underlying mechanism is usually not well understood. We decided to analyze some proteins involved in the catabolism of triglyceride-rich lipoproteins in patients with severe hypertriglyceridaemia. Methods Twenty-four survivors of acute hypertriglyceridaemic pancreatitis (cases) and 31 patients with severe hypertriglyceridaemia (controls) were included. Clinical and anthropometrical data, chylomicronaemia, lipoprotein profile, postheparin lipoprotein lipase mass and activity, hepatic lipase activity, apolipoprotein C II and CIII mass, apo E and A5 polymorphisms were assessed. Results Only five cases were found to have LPL mass and activity deficiency, all of them thin and having the first episode in childhood. No cases had apolipoprotein CII deficiency. No significant differences were found between the non-deficient LPL cases and the controls in terms of obesity, diabetes, alcohol consumption, drug therapy, gender distribution, evidence of fasting chylomicronaemia, lipid levels, LPL activity and mass, hepatic lipase activity, CII and CIII mass or apo E polymorphisms. However, the SNP S19W of apo A5 tended to be more prevalent in cases than controls (40% vs. 23%, NS). Conclusion Primary defects in LPL and C-II are rare in survivors of acute hypertriglyceridaemic pancreatitis; lipase activity measurements should be restricted to those having their first episode during chilhood. PMID:19534808

Alterations in adipokines in feline hepatic lipidosis.

Science.gov (United States)

Mazaki-Tovi, M; Abood, S K; Segev, G; Schenck, P A

2013-01-01

Feline hepatic lipidosis (HL) is associated with alterations in lipid and carbohydrate metabolism. The adipokines, adiponectin, and leptin have lipid-lowering and insulin-sensitizing effects. Serum concentrations of adiponectin and leptin are altered in feline HL. Client-owned cats: 55 healthy and 45 with liver disease. Cats with liver disease were categorized as having HL (n = 20), HL and concurrent disease (n = 19), or other liver disease (n = 6), based on clinical signs, laboratory findings, abdominal ultrasound examination as well as liver cytopathology, histopathology, or both. Serum samples were collected and body condition score determined. Mean serum concentrations of adiponectin were higher in overweight cats with HL (4.5 μg/mL), HL and concurrent disease (4.4 μg/mL), or other liver disease (6.1 μg/mL), as compared with healthy cats (1.5 μg/mL; P < .001, P < .001, and P = .04, respectively). Mean serum concentration of leptin was higher in cats with HL (9.8 ng/mL) or HL and concurrent disease (10.7 ng/mL) than healthy cats (4.9 ng/mL, P < .001 and P < .001, respectively). Cats with other liver disease had leptin concentration (4.9 ng/mL) similar to healthy cats. Concentrations of adiponectin were correlated with alanine aminotransferase activity (r = 0.40, P = .0069), and concentrations of leptin were correlated with alkaline phosphatase activity (r = 0.42, P = .0051) in cats with liver disease. Adipokine concentrations are altered in feline HL. Increased concentrations of adiponectin are related to liver disease, whereas increased concentrations of leptin are specifically related to HL. Copyright © 2013 by the American College of Veterinary Internal Medicine.

Hepatic lipidosis and other test findings in two captive adult porcupines (Erethizon dorsatum) dying from a "sudden death syndrome".

Science.gov (United States)

Barigye, Robert; Schamber, Ev; Newell, Teresa K; Dyer, Neil W

2007-11-01

Routine postmortem examination and histologic evaluation of tissue sections demonstrated hepatic lipidosis (HL) in 2 adult captive porcupines with a history of sudden death. The male porcupine had a markedly enlarged pale liver that microscopically showed large unilocular vacuoles within hepatocellular cytoplasm. The periparturient female had similar but less marked hepatic lesions and an incidental pulmonary mycosis. These findings suggest HL as an important differential of spontaneous death in captive porcupines. It is hypothesized that in addition to the widely documented causes, HL in captive porcupines may be specifically associated with nutritional imbalances caused by the feeding of unsuitable commercial diets. The possible association of the condition with dietary and other factors in captive porcupines needs to be thoroughly investigated.

The Effect of Tallow As Lipase Inducer on Total of Aspergillus Niger, Lipolitic Activity and Lipase Yield

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Manik Eirry Sawitri

2012-02-01

Full Text Available The objectives of this research was to determined of tallow addition with different concentration as lipase Aspergillus niger inducer to total of A. niger, lipolitic activity and lipase yield. The result showed that tallow addition as inducer in the lipase A. niger production gave no significant effect on total of A. niger (5.3 x 107 – 1.7 x 108 cfu/gram in the medium. Tallow addition gave a highly significant effect on lipolytic activity and yield of lipase A. niger. Lipolytic activity ranged between 32.0354 – 53.1197 U/mg protein, while the yield of lipase was 6.6418–7.8941 µg/ml. The conclusion of this research was the addition of tallow for 8% as the lipase inducer of A. niger on lipase production was  more effective to obtain the optimal result. Keywords : Tallow, lipase, inducer, Aspergillus niger

Von Hippel-Lindau disease (vHL)

DEFF Research Database (Denmark)

Binderup, Marie Louise Mølgaard; Bisgaard, Søs Marie Luise; Harbud, Vibeke

2013-01-01

These clinical guidelines outline the criteria and recommendations for diagnostic and genetic work-up of families suspected of von Hippel-Lindau disease (vHL), as well as recommendations for prophylactic surveillance for vHL patients. The guideline has been composed by the Danish Coordination Group...... for vHL which is comprised of Danish doctors and specialists interested in vHL. The recommendations are based on longstanding clinical experience, Danish original research, and extensive review of the international literature. vHL is a hereditary multi-tumour disease caused by germline mutations...... of the disease, and/or in individuals with a vHL-associated manifestation; i.e. a hemangioblastoma in the retina or the central nervous system, familial or bilateral pheochromocytomas, familial, multiple, or early onset renal cell carcinomas, and in individuals with an endolymphatic sac tumour in the inner ear...

Pilot Peter Hoag and HL-10

Science.gov (United States)

1969-01-01

Air Force Major Peter Hoag stands in front of the HL-10 Lifting Body. Maj. Hoag joined the HL-10 program in 1969 and made his first glide flight on June 6, 1969. He made a total of 8 flights in the HL-10. They included the fastest lifting-body flight, which reached Mach 1.861 on Feb. 18, 1970. The HL-10 was one of five heavyweight lifting-body designs flown at NASA's Flight Research Center (FRC--later Dryden Flight Research Center), Edwards, California, from July 1966 to November 1975 to study and validate the concept of safely maneuvering and landing a low lift-over-drag vehicle designed for reentry from space. Northrop Corporation built the HL-10 and M2-F2, the first two of the fleet of 'heavy' lifting bodies flown by the NASA Flight Research Center. The contract for construction of the HL-10 and the M2-F2 was $1.8 million. 'HL' stands for horizontal landing, and '10' refers to the tenth design studied by engineers at NASA's Langley Research Center, Hampton, Va. After delivery to NASA in January 1966, the HL-10 made its first flight on Dec. 22, 1966, with research pilot Bruce Peterson in the cockpit. Although an XLR-11 rocket engine was installed in the vehicle, the first 11 drop flights from the B-52 launch aircraft were powerless glide flights to assess handling qualities, stability, and control. In the end, the HL-10 was judged to be the best handling of the three original heavy-weight lifting bodies (M2-F2/F3, HL-10, X-24A). The HL-10 was flown 37 times during the lifting body research program and logged the highest altitude and fastest speed in the Lifting Body program. On Feb. 18, 1970, Air Force test pilot Peter Hoag piloted the HL-10 to Mach 1.86 (1,228 mph). Nine days later, NASA pilot Bill Dana flew the vehicle to 90,030 feet, which became the highest altitude reached in the program. Some new and different lessons were learned through the successful flight testing of the HL-10. These lessons, when combined with information from it's sister ship, the M2

HL-A27 and anterior uveitis.

Science.gov (United States)

Woodrow, J C; Mapstone, R; Anderson, J; Usher, N

1975-09-01

HL-A types were determined in 90 successive patients with non-granulomatous uveitis. Fifty-one were HL-A27 positive (55.7%) compared to 8.2% of controls. Of 16 patients with ankylosing spondylitis, 13 were HL-A27 positive, as were two patients with a history of Reiter's syndrome. Twenty-eight patients were HL-A27 positive but had no evidence of rheumatic disease. The findings are discussed in relation to the possible pathogenesis of uveitis.

Keeping HL-LHC accountable

CERN Multimedia

2015-01-01

This week saw the cost and schedule of the High Luminosity LHC (HL-LHC) and LHC Injectors Upgrade (LIU) projects come under close scrutiny from the external review committee set up for the purpose.    HL-LHC, whose implementation requires an upgrade to the CERN injector complex, responds directly to one of the key recommendations of the updated European Strategy for Particle Physics, which urges CERN to prepare for a ‘major luminosity upgrade’, a recommendation that is also perfectly in line with the P5 report on the US strategy for the field. Responding to this recommendation, CERN set up the HL-LHC project in 2013, partially supported by FP7 funding through the HiLumi LHC Design Study (2011-2015), and coordinated with the American LARP project, which oversees the US contribution to the upgrade. A key element of HL-LHC planning is a mechanism for receiving independent expert advice on all aspects of the project.  To this end, several technical reviews h...

Lipase H, a new member of the triglyceride lipase family synthesized by the intestine

NARCIS (Netherlands)

Jin, Weijun; Broedl, Uli C.; Monajemi, Houshang; Glick, Jane M.; Rader, Daniel J.

2002-01-01

We report here the molecular cloning of a novel member of the triglyceride lipase family, a 2.4-kb cDNA encoding human lipase H (LIPH) and the mouse ortholog (Liph). The human LIPH cDNA encodes a 451-amino-acid protein with a lipase domain. Mouse Liph shows 85% amino acid identity and 75% nucleotide

Activity and stability of immobilized lipases in lipase-catalyzed modification of peanut oil

OpenAIRE

Soumanou Mohamed M.; Edorh Aleodjrodo P.; Bornscheuer Uwe T.

2004-01-01

Fatty acid release during lipolysis of peanut oil using microbial free and immobilized lipases in aqueous media was developed. Immobilized lipase from Rhizomucor miehei (RML) gave the best result from its ability to clive different fatty acids from peanut oil in such media. In organic solvent, interesterification of peanut oil with tricaprylin using immobilized lipases from RML, Chromobacterium viscosum (CVL) and Candida rugosa (CRL) was performed. The best substrate molar ratio of tricapryli...

Biodiesel production with immobilized lipase: A review.

Science.gov (United States)

Tan, Tianwei; Lu, Jike; Nie, Kaili; Deng, Li; Wang, Fang

2010-01-01

Fatty acid alkyl esters, also called biodiesel, are environmentally friendly and show great potential as an alternative liquid fuel. Biodiesel is produced by transesterification of oils or fats with chemical catalysts or lipase. Immobilized lipase as the biocatalyst draws high attention because that process is "greener". This article reviews the current status of biodiesel production with immobilized lipase, including various lipases, immobilization methods, various feedstocks, lipase inactivation caused by short chain alcohols and large scale industrialization. Adsorption is still the most widely employed method for lipase immobilization. There are two kinds of lipase used most frequently especially for large scale industrialization. One is Candida antartica lipase immobilized on acrylic resin, and the other is Candida sp. 99-125 lipase immobilized on inexpensive textile membranes. However, to further reduce the cost of biodiesel production, new immobilization techniques with higher activity and stability still need to be explored. Copyright 2010 Elsevier Inc. All rights reserved.

Rhein Elicits In Vitro Cytotoxicity in Primary Human Liver HL-7702 Cells by Inducing Apoptosis through Mitochondria-Mediated Pathway

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Guy-Armel Bounda

2015-01-01

Full Text Available Objective. To study rhein-induced apoptosis signaling pathway and to investigate its molecular mechanisms in primary human hepatic cells. Results. Cell viability of HL-7702 cells treated with rhein showed significant decrease in dose-dependent manner. Following rhein treatment (25 μM, 50 μM, and 100 μM for 12 h, the detection of apoptotic cells was significantly analyzed by flow cytometry and nuclear morphological changes by Hoechst 33258, respectively. Fatty degeneration studies showed upregulation level of the relevant hepatic markers (P < 0.01. Caspase activities expressed significant upregulation of caspase-3, caspase-9, and caspase-8. Moreover, apoptotic cells by rhein were significantly inhibited by Z-LEHD-FMK and Z-DEVD-FMK, caspase-9 inhibitor, and caspase-3 inhibitor, respectively. Overproduction of reactive oxygen species, lipid peroxidation, and loss of mitochondrial membrane potential were detected by fluorometry. Additionally, NAC, a ROS scavenger, significantly attenuated rhein-induced oxidative damage in HL-7702 cells. Furthermore, real-time qPCR results showed significant upregulation of p53, PUMA, Apaf-1, and Casp-9 and Casp-3 mRNA, with no significant changes of Fas and Cytochrome-c. Immunoblotting revealed significant Cytochrome-c release from mitochondria into cytosol and no change in Fas expression. Conclusion. Taken together, these observations suggested that rhein could induce apoptosis in HL-7702 cells via mitochondria-mediated signal pathway with involvement of oxidative stress mechanism.

Organic Solvent Tolerant Lipases and Applications

Directory of Open Access Journals (Sweden)

Shivika Sharma

2014-01-01

Full Text Available Lipases are a group of enzymes naturally endowed with the property of performing reactions in aqueous as well as organic solvents. The esterification reactions using lipase(s could be performed in water-restricted organic media as organic solvent(s not only improve(s the solubility of substrate and reactant in reaction mixture but also permit(s the reaction in the reverse direction, and often it is easy to recover the product in organic phase in two-phase equilibrium systems. The use of organic solvent tolerant lipase in organic media has exhibited many advantages: increased activity and stability, regiospecificity and stereoselectivity, higher solubility of substrate, ease of products recovery, and ability to shift the reaction equilibrium toward synthetic direction. Therefore the search for organic solvent tolerant enzymes has been an extensive area of research. A variety of fatty acid esters are now being produced commercially using immobilized lipase in nonaqueous solvents. This review describes the organic tolerance and industrial application of lipases. The main emphasis is to study the nature of organic solvent tolerant lipases. Also, the potential industrial applications that make lipases the biocatalysts of choice for the present and future have been presented.

FRAKSINASI ENZIM LIPASE DARI ENDOSPERM KELAPA DENGAN METODE SALTING OUT (Lipase fractionation of Coconut Endosperm by Salting out Method

Directory of Open Access Journals (Sweden)

Moh. Su'i

2014-02-01

Full Text Available This research learns about fractionation of lipases activity from coconut endosperm by using ammonium sulphate of 0–15%; 15-30 %, 30–45 %, 45–60 %, 60–75 % and 75–90 %. The results showed that the fractions of 0–15% ; 30–45 %, 45–60 % and 60–75 % have lipase activity. Meanwhile, the highest activity was fractions of 60-75%. fractions of 15-30% and 75-90%  have no lipase enzym activity. Molecule weigh of lipase enzyme was 72 kDa. Keywords: Lipases, endosperm, coconut, fractionation, ammonium sulphate   ABSTRAK Penelitian ini mempelajari fraksinasi enzim lipase dari endosperm kelapa menggunakan ammonium sulfat. fraksinasi dilakukan dengan variasi konsentrasi ammonium sulfat 0–15% ; 15-30%; 30–45 %, 45–60 %, 60–75 % dan 75–90 %. Hasil penelitian menunjukkan bahwa enzim lipase terdapat pada fraksi 0–15% ; 30–45 %, 45–60 % dan fraksi 60–75 % dengan aktivitas enzim tertinggi pada fraksi 60-75%. Sedangkan fraksi 15-30% dan 75-90% tidak ada enzim lipase. Berat molekul enzim lipase pada semua fraksi 72 kDa. Kata kunci: Lipase, endosperm, fraksinasi, ammonium sulfat

Lipase kinetics: hydrolysis of triacetin by lipase from Candida cylindracea in a hollow-fiber membrane reactor

NARCIS (Netherlands)

Guit, R.P.M.; Kloosterman, M.; Meindersma, G.W.; Mayer, M.; Meijer, E.M.

1991-01-01

The aptitude of a hollow-fiber membrane reactor to det. lipase kinetics was investigated using the hydrolysis of triacetin catalyzed by lipase from C. cylindracea as a model system. The binding of the lipase to the membrane appears not to be very specific (surface adsorption), and probably its

OPTIMASI ISOLASI LIPASE INDIGENOUS BIJI KAKAO (Theobroma cacao L. The Optimizing of Isolation of Cocoa Bean Indogenous Lipase (Theobroma cacao L.

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I D. G. Mayun Permana

2012-05-01

Full Text Available The aim of the research is to optimize the isolation method of cocoa bean lipase. The research is held by determining the position of lipase on cocoa bean, varying extraction medium and isolation process. The result shows that the lipase of cocoa bean is   cytosolic enzyme. The defatting process do not increase the lipase activity. Polyphenols inhibit the lipase activity, so that removal of the polyphenol will increase the activity. Blocking the polyphenol with polyvinilpolypirrolidone (PVPP will also increase the activity.The optimum consentration of PVPP is 8 %. The lipase activity will reach the highest when homogenized for 10 menit at 10,000 rpm. The best medium extraction for lipase isolation is 0.15 M phosphate buffer pH 7.5 containing sucrose 0.6 M and CaCl  1.0 mM.   ABSTRAK Penelitian ini bertujuan untuk mengoptimasi isolasi lipase indigenous biji kakao. Optimasi diawali dengan menentukan keberadaan lipase kemudian optimasi medium ekstraksi dan proses ekstraksi. Hasil penelitian menunjukkan bahwa lipase berada dalam sitosol. Penghilangan lemak tidak meningkatkan aktivitas lipase. Senyawa polifenol menghambat aktivitas lipase dan penghilangan polifenol dapat meningkatkan aktivitas lipase. Polyvinilpolypirrolidone (PVPP dapat menghambat polifenol sehingga dapat meningkatkan aktivitas lipase. Konsentrasi PVPP optimum adalah 8 % dari berat biji kakao. Proses homogenisasi optimum diperoleh dalam waktu 10 menit pada kecepatan 10.000 rpm. Medium ekstraksi untuk isolasi lipase biji kakao terbaik adalah bufer fosfat 0,15 M  dan pH 7,5 yang mengandung sukrosa 0,6 M dan 1,0 mM CaCl .

Probiotic assessment of Enterococcus durans 6HL and Lactococcus lactis 2HL isolated from vaginal microflora.

Science.gov (United States)

Nami, Yousef; Abdullah, Norhafizah; Haghshenas, Babak; Radiah, Dayang; Rosli, Rozita; Khosroushahi, Ahmad Yari

2014-08-01

Forty-five lactic acid bacteria (LAB) were isolated from the vaginal specimens of healthy fertile women, and the identities of the bacteria were confirmed by sequencing of their 16S rDNA genes. Among these bacteria, only four isolates were able to resist and survive in low pH, bile salts and simulated in vitro digestion conditions. Lactococcus lactis 2HL, Enterococcus durans 6HL, Lactobacillus acidophilus 36YL and Lactobacillus plantarum 5BL showed the best resistance to these conditions. These strains were evaluated further to assess their ability to adhere to human intestinal Caco-2 cells. Lactococcus lactis 2HL and E. durans 6HL were the most adherent strains. In vitro tests under neutralized pH proved the antimicrobial activity of both strains. Results revealed that the growth of Escherichia coli O26, Staphylococcus aureus and Shigella flexneri was suppressed by both LAB strains. The antibiotic susceptibility tests showed that these strains were sensitive to all nine antibiotics: vancomycin, tetracycline, ampicillin, penicillin, gentamicin, erythromycin, clindamycin, sulfamethoxazole and chloramphenicol. These data suggest that E. durans 6HL and Lactococcus lactis 2HL could be examined further for their useful properties and could be developed as new probiotics. © 2014 The Authors.

HL-LHC Accelerator

CERN Document Server

Zimmermann, F

2013-01-01

The tentative schedule, key ingredients, as well as progress of pertinent R&D and component prototypes for the LHC luminosity upgrade, "HL-LHC," are reviewed. Also alternative scenarios based on performance-improving consolidations (PICs) instead of a full upgrade are discussed. Tentative time schedules and expected luminosity evolutions for the different scenarios are sketched. The important role of HL-LHC development as a step towards a future HE-LHC or VHE-LHC is finally highlighted. Presented at "Higgs & Beyond" Conference Tohoku University, Sendai 7 June 2013.

Familial lipoprotein lipase deficiency

Science.gov (United States)

... lack an enzyme called lipoprotein lipase. Without this enzyme, the body cannot break down fat from digested food. Fat particles called chylomicrons build up in the blood. Risk factors include a family history of lipoprotein lipase deficiency. The condition is usually ...

HL-LHC parameter space and scenarios

International Nuclear Information System (INIS)

Bruning, O.S.

2012-01-01

The HL-LHC project aims at a total integrated luminosity of approximately 3000 fb -1 over the lifetime of the HL-LHC. Assuming an exploitation period of ca. 10 years this goal implies an annual integrated luminosity of approximately 200 fb -1 to 300 fb -1 per year. This paper looks at potential beam parameters that are compatible with the HL-LHC performance goals and discusses briefly potential variation in the parameter space. It is shown that the design goal of the HL-LHC project can only be achieved with a full upgrade of the injector complex and the operation with β* values close to 0.15 m. Significant margins for leveling can be achieved for β* values close to 0.15 m. However, these margins can only be harvested during the HL-LHC operation if the required leveling techniques have been demonstrated in operation

Rannarootslaste suurmees Hans Pöhl / Olev Liivik

Index Scriptorium Estoniae

Liivik, Olev, 1975-

2011-01-01

Arvustus: Estlandssvenskarnas hövding. En biografi över Hans Pöhl (1876-1930), estlandssvenskarnas främste företrädare och ledare = Hans Pöhl - rannarootslaste eestvõileja : Hans Pöhl (1876-1930), Eesti rootslaste vaimse liidri ja valgustaja elulugu. Stockholm, 2010

Potencial de biocatálise enantiosseletiva de lipases microbianas Potential of enantioselective biocatalysis by microbial lipases

Directory of Open Access Journals (Sweden)

Patrícia de O. Carvalho

2005-08-01

Full Text Available Microbial lipases have a great potential for commercial applications due to their stability, selectivity and broad substrate specificity because many non-natural acids, alcohols or amines can be used as the substrate. Three microbial lipases isolated from Brazilian soil samples (Aspergillus niger; Geotrichum candidum; Penicillium solitum were compared in terms of their stability and as biocatalysts in the enantioselective esterification using racemic substrates in organic medium. The lipase from Aspergillus niger showed the highest activity (18.2 U/mL and was highly thermostable, retaining 90% and 60% activity at 50 ºC and 60 ºC after 1 hour, respectively. In organic medium, this lipase provided the best results in terms of enantiomeric excess of the (S-active acid (ee = 6.1% and conversion value (c = 20% in the esterification of (R,S-ibuprofen with 1-propanol in isooctane. The esterification reaction of the racemic mixture of (R,S-2-octanol with decanoic acid proceeded with high enantioselectivity when lipase from Aspergillus niger (E = 13.2 and commercial lipase from Candida antarctica (E = 20 were employed.

Application of alkaline thermo-stable lipase(s) enzyme produced from irradiated microbial isolate in the field of detergent technology

International Nuclear Information System (INIS)

Ahmed, O.E.A.M.S

2010-01-01

Due to continuous demand for manufacture of high quality, low coast industrial detergents containing lipolytic enzymes and due to continuous accumulation of enviro-agro-industrial wastes which are good and suitable conditions for growth and reproduction of pathogenic microorganisms, our study aims at isolating thermoalkalophilic lipase producer microorganisms from enviro-agro-industrial wastes and selection of the most potent isolate for studying physiological conditions controlling enzyme formation also purification characterization and some applications on purified and crude enzyme as bio-detergent. Some environmental and industrial wastes were collected from different places. The industrial wastes include, cotton seed, soyabean, sun flower, lin seed and olive oil wastes. Environmental wastes include poultry and fish wastes, all these wastes were dried at 70 degree C, grounded and used for isolation of microorganisms and lipase(s) production.Nine thermoalkalophilic bacterial isolates were isolated from enviro-agro-industrial wastes at ph 11.5 and 70 degree C. They were purified and screening for their ability of thermoalkalo-stable lipase(s) formation, this is followed by examining the effect of different nutritional media and exposure of bacterial isolates to different doses of gamma irradiation and the influence of these radiation on lipase(s) productivity by these isolates. From the results it was found that.1- The most potent lipase(s) forming bacterial isolates were isolates number B 2 and B 3 which cultivated on medium A amended with fish-wastes as being the best nutritional medium for enzyme formation. 2-Bacterial isolate B 2 finally was selected as being the most potent lipase(s) forming bacterial isolate cultivated on fish-wastes and yeast extract (in tap water) and identified according to key's of Bergey Manual of Systematic Bacteriology (1984) as being Bacillus brevis B 2 .The optimum culture conditions for maximum biosynthesis of extracellular lipase(s

Metabolic changes and induction of hepatic lipidosis during feed restriction in llamas.

Science.gov (United States)

Tornquist, S J; Cebra, C K; Van Saun, R J; Smith, B B; Mattoon, J S

2001-07-01

To determine whether feed restriction induces hepatic lipidosis (HL) in llamas and to evaluate the metabolic changes that develop during feed restriction. 8 healthy adult female llamas. Llamas were fed grass hay at a rate of 0.25% of their body weight per day for 13 to 28 days. Llamas were monitored by use of clinical observation, serum biochemical analyses, and ultrasound-guided liver biopsies. All 8 llamas lost weight and mobilized fat. Five llamas developed HL, including 4 that were nursing crias. During the period of feed restriction, mean serum concentration of bile acids and activities of aspartate aminotransferase (AST), sorbitol dehydrogenase (SDH), and gamma-glutamyl transferase (GGT) were significantly higher in llamas that developed HL, compared with llamas that did not. Mean insulin-to-cortisol concentration ratios were lower in llamas with HL before and up to 7 days of feed restriction, compared with those that did not develop HL. HL in llamas may be induced by severe feed restriction, particularly in the face of increased energy demand. Llamas with weight loss attributable to inadequate dietary intake may develop biochemical evidence of hepatopathy and HL. Increases in serum concentration of bile acids and activities of GGT, AST, and SDH may indicate the development of HL in llamas and identify affected animals for aggressive therapeutic intervention.

Prognostic markers in feline hepatic lipidosis: a retrospective study of 71 cats.

Science.gov (United States)

Kuzi, Sharon; Segev, Gilad; Kedar, Shay; Yas, Einat; Aroch, Itamar

2017-11-11

Feline hepatic lipidosis (HL) is a common, potentially life-threatening disease resulting from prolonged anorexia and increased catabolism. This retrospective study included cats diagnosed with HL based on liver cytology or histopathology (years 2004-2015), and aimed to identify clinical and laboratory parameters associated with mortality. The study included 71 cats (47 females and 24 males) and 85 control cats with non-HL diseases. Most HL cats (90 per cent) were mixed breed, neutered (70; 99 per cent), female (47; 66 per cent), indoor cats (56; 79 per cent), fed dry commercial diets (44 cats; 62 per cent), and with a median age of 7.5 years (range 1.5-16.0). Common primary conditions included gastrointestinal diseases, pancreatitis and cholangiohepatitis (31 cats; 44 per cent) and stressful events (14; 20 per cent). HL was idiopathic in 20 cats (28 per cent). The overall mortality was 38 per cent (27/71 cats). Older age, as well as dullness, weakness, ptyalism, hypoproteinaemia, hypoalbuminaemia, increased serum creatine kinase activity, hypocholesterolaemia and hepatic failure at presentation were significantly (P≤0.033) associated with mortality. The primary disease was unassociated with mortality. Worsening hypoalbuminaemia, hyperammonaemia, hyperbilirubinaemia, electrolyte disorders, and occurrence of cavitary effusions or hypotension during hospitalisation were significantly (P≤0.045) associated with mortality. A decrease of serum β-hydroxybutyrate during hospitalisation was significantly (P=0.01) associated with survival, likely reflecting improvement in the catabolic state. The identified risk factors may be therapeutic targets. © British Veterinary Association (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Activity and stability of immobilized lipases in lipase-catalyzed modification of peanut oil

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Soumanou Mohamed M.

2004-11-01

Full Text Available Fatty acid release during lipolysis of peanut oil using microbial free and immobilized lipases in aqueous media was developed. Immobilized lipase from Rhizomucor miehei (RML gave the best result from its ability to clive different fatty acids from peanut oil in such media. In organic solvent, interesterification of peanut oil with tricaprylin using immobilized lipases from RML, Chromobacterium viscosum (CVL and Candida rugosa (CRL was performed. The best substrate molar ratio of tricaprylin to peanut oil found was in the range 0.7 to 0.8. Using substrate molar ratio 0.7, high amount of structured triglyceride ST (about 35% MLM, 44% LML triglyceride fractions was obtained with lipase from RML in n-hexane. The results found in solvent free system were in some cases quite similar to that obtained in organic solvent. In nine successive batch interesterification in solvent free medium using immobilized RML and CRL, no significant loss of amount of both produced triacylglycerol fractions until batch 7 was observed with RML.

Does non-alcoholic fatty liver impair alterations of plasma lipoproteins and associated factors in metabolic syndrome?

Science.gov (United States)

Lucero, Diego; Zago, Valeria; López, Graciela I; Graffigna, Mabel; López, Gustavo H; Fainboim, Hugo; Miksztowicz, Verónica; Gómez Rosso, Leonardo; Belli, Susana; Levalle, Oscar; Berg, Gabriela; Brites, Fernando; Wikinski, Regina; Schreier, Laura

2011-03-18

Hepatic steatosis (HS) is closely associated to metabolic syndrome (MS). Both, VLDL-triglyceride oversecretion and intrahepatic deposits, can take place. We evaluated VLDL characteristics, CETP, hepatic lipase (HL), IDL and small dense LDL (sdLDL), in patients with HS associated to MS. We studied 3 groups matched by age and sex: 25 MS patients with HS (diagnosed by ultrasonography), 25 MS patients without HS and 25 healthy controls. Main measurements were: lipid profile, free fatty acids, VLDL composition, VLDL size by HPLC, CETP and HL activities, IDL-cholesterol and sdLDL-cholesterol. Patients with HS presented higher triglyceride levels, HOMA-IR and free fatty acids, VLDL mass and VLDL-apoB (p<0.05). No differences in VLDL composition were observed. MS groups presented higher proportion of large VLDL than controls (p<0.05). HS group showed higher CETP than controls (p=0.01) and almost higher than MS without HS (p=0.06). CETP correlated with VLDL-cholesterol content, r=0.48, p<0.005. The increase in sdLDL-cholesterol correlated with CETP (r=0.47) and HL (r=0.56), independent of insulin resistance (p<0.003). Despite intrahepatic fat, patients with HS secreted higher number of VLDL particles. CETP would have a remodeling action on VLDL in circulation, enriching it in cholesterol and also favoring, together with HL, the formation of sdLDL. Copyright © 2010 Elsevier B.V. All rights reserved.

Lipase Test: MedlinePlus Lab Test Information

Science.gov (United States)

... page: https://medlineplus.gov/labtests/lipasetest.html Lipase Test To use the sharing features on this page, please enable JavaScript. What is a lipase test? Lipase is a type of protein made by ...

HL7 Messaging Engine with Customizable Translation System

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PRODAN, R.

2010-05-01

Full Text Available This paper introduces a new client-server messaging engine used to exchange clinical data between various medical software applications. Our portal uses the HL7 (Health Level Seven messaging standard to provide translated clinical data to HL7 and non-HL7 client applications. We used HL7 because this standard is worldwide used to facilitate the communication between clinical applications.

21 CFR 184.1415 - Animal lipase.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Animal lipase. 184.1415 Section 184.1415 Food and... Substances Affirmed as GRAS § 184.1415 Animal lipase. (a) Animal lipase (CAS Reg. No. 9001-62-1) is an enzyme preparation obtained from edible forestomach tissue of calves, kids, or lambs, or from animal pancreatic...

Biochemical Characterization of Lipases Obtained from Acinetobacter psychrotolerans Strains

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Şule SEREN

2017-12-01

Full Text Available In this study, extracellular lipases obtained from Acinetobacter psychrotolerans strains (Xg1 and Xg2 were characterized. The effects of varying pH values (3.0-10.0 and various temperatures (10-90 °C on lipase activities were examined. Also the effects of different metal ions, organic solvents and detergents on lipases were studied. The extracellular crude lipases were concentrated using ultrafiltration. Zymogram analysis of these lipases was performed. Lipases exhibited maximum activity at pH 8 and 30 °C.  While lipase obtained from the Xg1 strain exhibited the highest stability in the presence of various organic solvents, including hexane, ethyl acetate, chloroform and N,N dietil formamide, lipase obtained from the Xg2 strain was sensitive in the presence of isopropanol, acetonitrile, and butan-1-ol. The lipases of the Xg1 and Xg2 strains were inhibited in the presence of Cu2+ and Zn2+. Also, the lipase of the Xg1 strain was inhibited in the presence of Fe3+. In the presence of EDTA, the lipase activities of the Xg1 and Xg2 strains were partially inhibited. In presence of SDS, they were exactly inhibited. According to the zymogram results, the molecular weights of the lipases obtained from the Acinetobacter psychrotolerans Xg1 and Xg2 strains have been found approximately 37 and 30 kDa, respectively.

Von Hippel-Lindau disease (vHL)

DEFF Research Database (Denmark)

Binderup, Marie Louise Mølgaard; Bisgaard, Søs Marie Luise; Harbud, Vibeke

2013-01-01

for vHL which is comprised of Danish doctors and specialists interested in vHL. The recommendations are based on longstanding clinical experience, Danish original research, and extensive review of the international literature. vHL is a hereditary multi-tumour disease caused by germline mutations....../MRI of the abdomen, e) annual plasma-metanephrine, plasma-normetanephrine, and plasma-chromogranin A tests, and f) annual hearing examination at a department of audiology. It is advised that one doctor takes on the responsibility of coordination of and referral to the many examinations, and the communication...

Maximization of Intracellular Lipase Production in a Lipase-Overproducing Mutant Derivative of Rhizopus oligosporus DGM 31: A Kinetic Study

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Tehreema Iftikhar

2008-01-01

Full Text Available Regulation and maximization of lipase production in a mutant derivative of R. oligosporus has been investigated using different substrates, inoculum sizes, pH of the medium, temperature, and nitrogen sources in shake flask experiments and batch fermentation in a fermentor. The production of intracellular lipase was improved 3 times following medium optimization involving one-at-a-time approach and aeration in the fermentor. Interestingly, intracellular lipase was poorly induced by oils, instead its production was induced by sugars, mainly starch, lactose, sucrose, xylose, glucose and glycerol. Dependent variables studied were cell mass, lipase activity, lipase yield, lipase specific and volumetric rate of formation. It was confirmed that lipase production in the derepressed mutant is sufficiently uncoupled from catabolite repression. The results of average specific productivities at various temperatures worked out according to the Arrhenius equation revealed that mutation decreased the magnitude of enthalpy and entropy demand in the inactivation equilibrium during product formation, suggesting that mutation made the metabolic network of the organism thermally more stable. The highest magnitudes of volumetric productivity (QP=490 IU/(L·h and other product attributes of lipase formation occurring on optimized medium in the fermentor are greater than the values reported by other workers. The purified enzyme is monomeric in nature and exhibits stability up to 80 °C and pH=6.0–8.0. Activation energy, enthalpy and entropy of catalysis at 50 °C, and magnitudes of Gibbs free energy for substrate binding, transition state stabilization and melting point indicated that this lipase is highly thermostable.

Lipase production by recombinant strains of Aspergillus niger expressing a lipase-encoding gene from Thermomyces lanuginosus

DEFF Research Database (Denmark)

Prathumpai, Wai; Flitter, S.J.; Mcintyre, Mhairi

2004-01-01

Two recombinant strains of Aspergillus niger (NW 297-14 and NW297-24) producing a heterologous lipase from Thermomyces lanuginosus were constructed. The heterologous lipase was expressed using the TAKA amylase promoter from Aspergillus oryzae. The production kinetics of the two strains on different...... shows that it is possible to obtain high productivities of heterologous fungal enzymes in A. niger. However, SDS-PAGE analysis showed that most of the produced lipase was bound to the cell wall....

Enhancement patterns and pseudo-washout of hepatic haemangiomas on gadoxetate disodium-enhanced liver MRI

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Kim, Bohyun [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of); Ajou University School of Medicine, Department of Radiology, Suwon (Korea, Republic of); Byun, Jae Ho; Kim, Hyoung Jung; Won, Hyung Jin; Kim, So Yeon; Shin, Yong Moon; Kim, Pyo Nyun [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of)

2016-01-15

To compare the enhancement patterns and prevalence of pseudo-washout between rapidly and slowly enhancing hepatic haemangiomas on gadoxetate disodium-enhanced MRI in patients with chronic liver disease (CLD) and healthy liver (HL). On gadoxetate disodium-enhanced MRI, the extent of intralesional arterial enhancement >50 % and ≤50 % of lesions was defined as rapid and slow enhancement, respectively. The enhancement patterns and presence of pseudo-washout during the portal venous phase (PVP) and transitional phase (TP) of 74 hepatic haemangiomas were retrospectively evaluated in the CLD and HL groups. Sequential changes of signal-to-noise ratio (SNR) were measured in unenhanced phase, PVP and TP. Irrespective of hepatic health status, pseudo-washout in TP was significantly more common in the rapidly enhancing haemangiomas (p ≤ 0.026). In both groups, rapidly enhancing haemangiomas showed complete or progressive incomplete enhancement in PVP, which either lasted or transformed to pseudo-washout in TP, whereas slowly enhancing haemangiomas showed progressive incomplete enhancement in PVP and TP. SNR of hepatic parenchyma continued to rise until TP, whereas that of portal vein and haemangioma falls in TP. Regardless of CLD, pseudo-washout in TP was more common in rapidly than in slowly enhancing haemangiomas, with enhancement patterns differing in the two subgroups. (orig.)

Enhancement patterns and pseudo-washout of hepatic haemangiomas on gadoxetate disodium-enhanced liver MRI

International Nuclear Information System (INIS)

Kim, Bohyun; Byun, Jae Ho; Kim, Hyoung Jung; Won, Hyung Jin; Kim, So Yeon; Shin, Yong Moon; Kim, Pyo Nyun

2016-01-01

To compare the enhancement patterns and prevalence of pseudo-washout between rapidly and slowly enhancing hepatic haemangiomas on gadoxetate disodium-enhanced MRI in patients with chronic liver disease (CLD) and healthy liver (HL). On gadoxetate disodium-enhanced MRI, the extent of intralesional arterial enhancement >50 % and ≤50 % of lesions was defined as rapid and slow enhancement, respectively. The enhancement patterns and presence of pseudo-washout during the portal venous phase (PVP) and transitional phase (TP) of 74 hepatic haemangiomas were retrospectively evaluated in the CLD and HL groups. Sequential changes of signal-to-noise ratio (SNR) were measured in unenhanced phase, PVP and TP. Irrespective of hepatic health status, pseudo-washout in TP was significantly more common in the rapidly enhancing haemangiomas (p ≤ 0.026). In both groups, rapidly enhancing haemangiomas showed complete or progressive incomplete enhancement in PVP, which either lasted or transformed to pseudo-washout in TP, whereas slowly enhancing haemangiomas showed progressive incomplete enhancement in PVP and TP. SNR of hepatic parenchyma continued to rise until TP, whereas that of portal vein and haemangioma falls in TP. Regardless of CLD, pseudo-washout in TP was more common in rapidly than in slowly enhancing haemangiomas, with enhancement patterns differing in the two subgroups. (orig.)

Immobilization of Isolated Lipase From Moldy Copra (Aspergillus Oryzae

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Seniwati Dali

2011-01-01

Full Text Available Enzyme immobilization is a recovery technique that has been studied in several years, using support as a media to help enzyme dissolutions to the reaction substrate. Immobilization method used in this study was adsorption method, using specific lipase from Aspergillus oryzae. Lipase was partially purified from the culture supernatant of Aspergillus oryzae. Enzyme was immobilized by adsorbed on silica gel. Studies on free and immobilized lipase systems for determination of optimum pH, optimum temperature, thermal stability and reusability were carried out. The results showed that free lipase had optimum pH 8,2 and optimum temperature 35 °C while the immobilized lipase had optimum 8,2 and optimum temperature 45 °C. The thermal stability of the immobilized lipase, relative to that of the free lipase, was markedly increased. The immobilized lipase can be reused for at least six times.

Lipase immobilization and production of fatty acid methyl esters from canola oil using immobilized lipase

International Nuclear Information System (INIS)

Yuecel, Yasin; Demir, Cevdet; Dizge, Nadir; Keskinler, Buelent

2011-01-01

Lipase enzyme from Aspergillus oryzae (EC 3.1.1.3) was immobilized onto a micro porous polymeric matrix which contains aldehyde functional groups and methyl esters of long chain fatty acids (biodiesel) were synthesized by transesterification of crude canola oil using immobilized lipase. Micro porous polymeric matrix was synthesized from styrene-divinylbenzene (STY-DVB) copolymers by using high internal phase emulsion technique and two different lipases, Lipozyme TL-100L ® and Novozym 388 ® , were used for immobilization by both physical adsorption and covalent attachment. Biodiesel production was carried out with semi-continuous operation. Methanol was added into the reactor by three successive additions of 1:4 M equivalent of methanol to avoid enzyme inhibition. The transesterification reaction conditions were as follows: oil/alcohol molar ratio 1:4; temperature 40 o C and total reaction time 6 h. Lipozyme TL-100L ® lipase provided the highest yield of fatty acid methyl esters as 92%. Operational stability was determined with immobilized lipase and it indicated that a small enzyme deactivation occurred after used repeatedly for 10 consecutive batches with each of 24 h. Since the process is yet effective and enzyme does not leak out from the polymer, the method can be proposed for industrial applications. -- Research highlights: → Lipozyme TL-100L and Novozym 388 were immobilized onto micro porous polymeric matrix by both physical adsorption and covalent linking. → Immobilized enzymes were used for synthesis of fatty acid methyl esters by transesterification of canola oil and methanol using semi-continuous operation system. → According to chromatographic analysis, Lipase Lipozyme TL-100L resulted in the highest yield of methyl ester as 92%.

Wolman's disease and cholesteryl ester storage disorder: the phenotypic spectrum of lysosomal acid lipase deficiency.

Science.gov (United States)

Pericleous, Marinos; Kelly, Claire; Wang, Tim; Livingstone, Callum; Ala, Aftab

2017-09-01

Lysosomal acid lipase deficiency is a rare, autosomal recessive condition caused by mutations in the gene encoding lysosomal acid lipase (LIPA) that result in reduced or absent activity of this essential enzyme. The severity of the resulting disease depends on the nature of the underlying mutation and magnitude of its effect on enzymatic function. Wolman's disease is a severe disorder that presents during infancy, resulting in failure to thrive, hepatomegaly, and hepatic failure, and an average life expectancy of less than 4 months. Cholesteryl ester storage disorder arises later in life and is less severe, although the two diseases share many common features, including dyslipidaemia and transaminitis. The prevalence of these diseases has been estimated at one in 40 000 to 300 000, but many cases are undiagnosed and unreported, and awareness among clinicians is low. Lysosomal acid lipase deficiency-which can be diagnosed using dry blood spot testing-is often misdiagnosed as non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), hereditary dyslipidaemia, or cryptogenic cirrhosis. There are no formal guidelines for treatment of these patients, and treatment options are limited. In this Review we appraise the existing literature on Wolman's disease and cholesteryl ester storage disease, and discuss available treatments, including enzyme replacement therapy, oral lipid-lowering therapy, stem-cell transplantation, and liver transplantation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Metabolic and hormonal alterations in cats with hepatic lipidosis.

Science.gov (United States)

Brown, B; Mauldin, G E; Armstrong, J; Moroff, S D; Mauldin, G N

2000-01-01

Hepatic lipidosis in cats is a commonly diagnosed hepatobiliary disease of unknown cause. The purpose of this prospective study was to characterize the blood hormone and lipid status of cats with hepatic lipidosis, and to compare this status to that of cats with other types of liver disease and to control cats. Twenty-three cats with hepatic disease were assigned to 1 of 2 groups on the basis of cytopathologic or histopathologic examination of the liver: group 1, hepatic lipidosis (n = 18); or group 2, cholangiohepatitis (n = 5). Ten healthy young adult cats were used as controls. Food was withheld from control animals for 24 hours before blood collection. Concentrations of plasma glucagon and serum insulin, cortisol, thyroxine, triglycerides, cholesterol, phospholipids, and nonesterified fatty acids (NEFAs) were determined in all cats, in addition to routine hematologic and serum biochemical testing. Cats with hepatic lipidosis had higher serum NEFA concentrations than cats with cholangiohepatitis or control cats (P lipidosis or control cats (P hepatic lipidosis. Serum insulin concentrations were significantly higher in control cats than in diseased cats (P hepatic disease. The high concentration of NEFAs in cats with hepatic lipidosis suggests that at least 1 factor in the pathogenesis of this syndrome may involve the regulation of hormone-sensitive lipase.

Mechanism of acetaldehyde-induced deactivation of microbial lipases

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Jaeger Karl E

2011-02-01

Full Text Available Abstract Background Microbial lipases represent the most important class of biocatalysts used for a wealth of applications in organic synthesis. An often applied reaction is the lipase-catalyzed transesterification of vinyl esters and alcohols resulting in the formation of acetaldehyde which is known to deactivate microbial lipases, presumably by structural changes caused by initial Schiff-base formation at solvent accessible lysine residues. Previous studies showed that several lipases were sensitive toward acetaldehyde deactivation whereas others were insensitive; however, a general explanation of the acetaldehyde-induced inactivation mechanism is missing. Results Based on five microbial lipases from Candida rugosa, Rhizopus oryzae, Pseudomonas fluorescens and Bacillus subtilis we demonstrate that the protonation state of lysine ε-amino groups is decisive for their sensitivity toward acetaldehyde. Analysis of the diverse modification products of Bacillus subtilis lipases in the presence of acetaldehyde revealed several stable products such as α,β-unsaturated polyenals, which result from base and/or amino acid catalyzed aldol condensation of acetaldehyde. Our studies indicate that these products induce the formation of stable Michael-adducts at solvent-accessible amino acids and thus lead to enzyme deactivation. Further, our results indicate Schiff-base formation with acetaldehyde to be involved in crosslinking of lipase molecules. Conclusions Differences in stability observed with various commercially available microbial lipases most probably result from different purification procedures carried out by the respective manufacturers. We observed that the pH of the buffer used prior to lyophilization of the enzyme sample is of utmost importance. The mechanism of acetaldehyde-induced deactivation of microbial lipases involves the generation of α,β-unsaturated polyenals from acetaldehyde which subsequently form stable Michael-adducts with the

Proteomic analysis of cell proliferation in a human hepatic cell line (HL-7702) induced by perfluorooctane sulfonate using iTRAQ

Energy Technology Data Exchange (ETDEWEB)

Cui, Ruina; Zhang, Hongxia [Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 (China); Guo, Xuejiang [State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing 210029 (China); Cui, Qianqian; Wang, Jianshe [Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 (China); Dai, Jiayin, E-mail: daijy@ioz.ac.cn [Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101 (China)

2015-12-15

Highlights: • PFOS stimulates cell proliferation of human liver cell line (HL-7702). • Differential expressed proteins are identified by iTRAQ. • Most of differential proteins caused by PFOS are related to cell proliferation. • Up-regulation of cyclin/cdk by PFOS plays a role in driving cells into cell cycle. - Abstract: Perfluorooctane sulfonate (PFOS) is a commonly used and widely distributed perfluorinated compound proven to cause adverse health outcomes. However, how PFOS affects liver cell proliferation is not well understood. In this experiment, we exposed a human liver cell line (HL-7702) to 50 μM PFOS for 48 h and 96 h. We identified 52 differentially expressed proteins using a quantitative proteomic approach. Among them, 27 were associated with cell proliferation, including hepatoma-derived growth factor (Hdgf) and proliferation biomarkers Mk167 (Ki67) and Top2α. Results from MTT, cell counting, and cell cycle analysis showed low-dose PFOS (<200 μM) stimulated HL-7702 cell viability at 48 h and 96 h, reduced the G0/G1 percentage, and increased the S + G2/M percentage. Moreover, levels of Cyclin D1, Cyclin E2, Cyclin A2, Cyclin B1 and their partner Cdks were elevated, and the expression of regulating proteins like c-Myc, p53, p21 waf/cip1 and Myt1, as well as the phosphorylation levels of p-Wee1(S642), p-Chk1(S345) and p-Chk2(T68), were disturbed. We hypothesized that low-dose PFOS stimulated HL-7702 proliferation by driving cells into G1 through elevating cyclins/cdks expression, and by promoting cell cycle progression through altering other regulating proteins. This research will shed light on the mechanisms behind PFOS-mediated human hepatotoxicity.

Proteomic analysis of cell proliferation in a human hepatic cell line (HL-7702) induced by perfluorooctane sulfonate using iTRAQ

International Nuclear Information System (INIS)

Cui, Ruina; Zhang, Hongxia; Guo, Xuejiang; Cui, Qianqian; Wang, Jianshe; Dai, Jiayin

2015-01-01

Highlights: • PFOS stimulates cell proliferation of human liver cell line (HL-7702). • Differential expressed proteins are identified by iTRAQ. • Most of differential proteins caused by PFOS are related to cell proliferation. • Up-regulation of cyclin/cdk by PFOS plays a role in driving cells into cell cycle. - Abstract: Perfluorooctane sulfonate (PFOS) is a commonly used and widely distributed perfluorinated compound proven to cause adverse health outcomes. However, how PFOS affects liver cell proliferation is not well understood. In this experiment, we exposed a human liver cell line (HL-7702) to 50 μM PFOS for 48 h and 96 h. We identified 52 differentially expressed proteins using a quantitative proteomic approach. Among them, 27 were associated with cell proliferation, including hepatoma-derived growth factor (Hdgf) and proliferation biomarkers Mk167 (Ki67) and Top2α. Results from MTT, cell counting, and cell cycle analysis showed low-dose PFOS (<200 μM) stimulated HL-7702 cell viability at 48 h and 96 h, reduced the G0/G1 percentage, and increased the S + G2/M percentage. Moreover, levels of Cyclin D1, Cyclin E2, Cyclin A2, Cyclin B1 and their partner Cdks were elevated, and the expression of regulating proteins like c-Myc, p53, p21 waf/cip1 and Myt1, as well as the phosphorylation levels of p-Wee1(S642), p-Chk1(S345) and p-Chk2(T68), were disturbed. We hypothesized that low-dose PFOS stimulated HL-7702 proliferation by driving cells into G1 through elevating cyclins/cdks expression, and by promoting cell cycle progression through altering other regulating proteins. This research will shed light on the mechanisms behind PFOS-mediated human hepatotoxicity.

Biodegradable products by lipase biocatalysis.

Science.gov (United States)

Linko, Y Y; Lämsä, M; Wu, X; Uosukainen, E; Seppälä, J; Linko, P

1998-11-18

The interest in the applications of biocatalysis in organic syntheses has rapidly increased. In this context, lipases have recently become one of the most studied groups of enzymes. We have demonstrated that lipases can be used as biocatalyst in the production of useful biodegradable compounds. A number of examples are given. 1-Butyl oleate was produced by direct esterification of butanol and oleic acid to decrease the viscosity of biodiesel in winter use. Enzymic alcoholysis of vegetable oils without additional organic solvent has been little investigated. We have shown that a mixture of 2-ethyl-1-hexyl esters can be obtained in a good yield by enzymic transesterification from rapeseed oil fatty acids for use as a solvent. Trimethylolpropane esters were also similarly synthesized as lubricants. Finally, the discovery that lipases can also catalyze ester syntheses and transesterification reactions in organic solvent systems has opened up the possibility of enzyme catalyzed production of biodegradable polyesters. In direct polyesterification of 1,4-butanediol and sebacic acid, polyesters with a mass average molar mass of the order of 56,000 g mol-1 or higher, and a maximum molar mass of about 130,000 g mol-1 were also obtained by using lipase as biocatalyst. Finally, we have demonstrated that also aromatic polyesters can be synthesized by lipase biocatalysis, a higher than 50,000 g mol-1 mass average molar mass of poly(1,6-hexanediyl isophthalate) as an example.

Lipase entrapment in PVA/Chitosan biodegradable film for reactor coatings

Energy Technology Data Exchange (ETDEWEB)

Batista, Karla A. [Departamento de Bioquímica e Biologia Molecular, Laboratório de Química de Proteínas, Universidade Federal de Goiás, Cx. Postal 131, 74001-970, Goiânia, GO (Brazil); Lopes, Flavio Marques [Departamento de Bioquímica e Biologia Molecular, Laboratório de Química de Proteínas, Universidade Federal de Goiás, Cx. Postal 131, 74001-970, Goiânia, GO (Brazil); Unidade Universitária de Ciências Exatas e Tecnológicas, Universidade Estadual de Goiás, Anápolis, GO (Brazil); Yamashita, Fabio [Departamento de Tecnologia de Alimentos e Medicamentos, Laboratório de Tecnologia, Universidade Estadual de Londrina, Cx. Postal 6001, CEP 86051-990, Londrina, PR (Brazil); Fernandes, Kátia Flávia, E-mail: katia@icb.ufg.br [Departamento de Bioquímica e Biologia Molecular, Laboratório de Química de Proteínas, Universidade Federal de Goiás, Cx. Postal 131, 74001-970, Goiânia, GO (Brazil)

2013-04-01

This study reports the development and characterization of novel biodegradable film, based on chitosan and polyvinyl alcohol containing lipase entrapped. The films showed a thickness of 70.4 and 79 μm to PVA/Chitosan and PVA/Chitosan/Lipase, respectively. The entrapment of lipase in PVA/Chitosan film resulted in increasing of 69.4% tensile strength (TS), and 52.4% of elongation. SEM images showed the formation of a continuous film, without pores or cracks. The lipase entrapment efficiency was estimated in 92% and the films were repeatedly used for 25 hydrolytic cycles, maintaining 62% of initial activity. The PVA/Chitosan/Lipase film was used for olive oil hydrolysis of high performance. These results indicate that PVA/Chitosan/Lipase is a promising material for biotechnology applications such as triacylglycerol hydrolysis and biodiesel production. - Highlights: ► Development and characterization of PVA/Chitosan biodegradable film ► Lipase immobilization onto PVA/Chitosan film ► PVA/Chitosan/Lipase film for reactor coating ► Olive oil hydrolysis using PVA/Chitosan/Lipase film.

Lipase entrapment in PVA/Chitosan biodegradable film for reactor coatings

International Nuclear Information System (INIS)

Batista, Karla A.; Lopes, Flavio Marques; Yamashita, Fabio; Fernandes, Kátia Flávia

2013-01-01

This study reports the development and characterization of novel biodegradable film, based on chitosan and polyvinyl alcohol containing lipase entrapped. The films showed a thickness of 70.4 and 79 μm to PVA/Chitosan and PVA/Chitosan/Lipase, respectively. The entrapment of lipase in PVA/Chitosan film resulted in increasing of 69.4% tensile strength (TS), and 52.4% of elongation. SEM images showed the formation of a continuous film, without pores or cracks. The lipase entrapment efficiency was estimated in 92% and the films were repeatedly used for 25 hydrolytic cycles, maintaining 62% of initial activity. The PVA/Chitosan/Lipase film was used for olive oil hydrolysis of high performance. These results indicate that PVA/Chitosan/Lipase is a promising material for biotechnology applications such as triacylglycerol hydrolysis and biodiesel production. - Highlights: ► Development and characterization of PVA/Chitosan biodegradable film ► Lipase immobilization onto PVA/Chitosan film ► PVA/Chitosan/Lipase film for reactor coating ► Olive oil hydrolysis using PVA/Chitosan/Lipase film

Rat lingual lipase: partial purification, hydrolytic properties, and comparison with pancreatic lipase.

Science.gov (United States)

Roberts, I M; Montgomery, R K; Carey, M C

1984-10-01

We have partially purified lingual lipase from the serous glands of rat tongue. With a combination of Triton X-100 extraction or Triton X-114 phase-separation techniques, Bio-Bead SM-2 treatment, dialysis, and gel filtration on Sephadex G-200 or Sephacryl S-300, we obtained a sparingly soluble lipid-free protein demonstrating hydrolytic activity against triglycerides and negligible phospholipase or cholesteryl esterase activities. Compared with homogenate, specific activities of the enzyme were enriched 3- to 5-fold prior to gel filtration and 10-fold after gel filtration. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration under denaturing conditions (6 M guanidine X HCl or 0.1% sodium dodecyl sulfate) revealed one major glycoprotein band with Mr approximately 50,000. Gel filtration of the active enzyme in 0.1% Triton X-100 gave an Mr approximately 270,000-300,000, suggesting extensive self-aggregation. With both tributyrin and triolein, the pH optimum of the purified enzyme was 4.0 and activity extended from pH 2.0 to 8.0. In contrast to purified human pancreatic lipase, lingual lipase hydrolyzed triglyceride emulsions and mixed micelles stabilized with both short-chain (dihexanoyl) and long-chain (egg) lecithin and were inhibited only slightly (18-25%) by micellar concentrations of two common bile salts, taurodeoxycholate and taurocholate. Our results suggest that the hydrolysis of dietary fat by lingual lipase may extend from the pharynx through the esophagus and stomach and into the upper small intestine.

Preliminary results of MHD stability in HL-1 tokamak

International Nuclear Information System (INIS)

Zheng Yongzhen; Ma Tengcai; Xiao Zhenggui Cai Renfang

1987-01-01

In this paper, MHD activities of HL-1 tokamak plasma are studied with Fourier transform and correlatio analysis. The poloidal modes m = 1, 2, 3,4 and toroidal modes n of MHD magnetic fluctuation signals are detected. Methods for suppressing MHD instabilities are suggested and tested, after MHD instabilities are studied in HL-1. The effects of MHD characteristics in the beginning stage of discharge on the whole process of discharge are analyzed. The disruption, in HL-1 device could be divided into three kinds: internal disruption, minor disruption and major disruption. The result shows that HL-1 will have a better operation condition if internal disruption appears. In is end, the stable operation region of HL-1 tokamak is also given

Catalytic Properties of Lipase Extracts from Aspergillus niger

Directory of Open Access Journals (Sweden)

Cintia M. Romero

2006-01-01

Full Text Available Screening of lipolytic strains using Rhodamine-B/olive oil plate technique allowed the selection of Aspergillus niger MYA 135. Lipase production in submerged culture containing 2 % olive oil was enhanced by more than 50 % compared to basal cultural conditions. Optimal catalytic conditions for olive oil-induced lipase were pH=6.5 and 30–35 °C. These values were shifted to the acid region (4.0–6.5 and 35–37 °C when lipase extract was produced under basal conditions. Slight changes of the residual lipase activity against the pH were found. However, preincubation at either 37 or 40 °C caused an increase in the olive oil-inducible lipolytic activity. On the contrary, lipase residual activity decreases in the 30–55 °C range when it was produced in basal medium. Lipolytic extracts were almost not deactivated in presence of 50 % water-miscible organic solvents. However, water-immiscible aliphatic solvents reduced the lipase activity between 20 and 80 %.

Isolation and analysis of lipase-overproducing mutants of Serratia marcescens.

Science.gov (United States)

Kawai, E; Akatsuka, H; Sakurai, N; Idei, A; Matsumae, H; Shibatani, T; Komatsubara, S; Omori, K

2001-01-01

We have isolated a lipase-overproducing mutant, GE14, from Serratia marcescens 8000 after three rounds of N-methyl-N'-nitro-N-nitrosoguanidine mutagenesis. The mutant GE14 produced 95 kU/ml of extracellular lipase in the lipase medium, which was about threefold higher than that of produced by the original strain 8000. Enzymatic characteristics including specific activity of purified lipases from culture supernatants of GE14 and 8000 were almost same. The lipase gene (lipA) of GE14 contained two base substitutions; one in the promoter region and another in the N-terminal region of the lipA gene without an amino acid substitution. Promoter analysis using lipA-lacZ fusion plasmids revealed that these substitutions were responsible for the increase in the lipA expression level, independently. In contrast, no base substitution was found in the genes encoding the lipase secretion device, the Lip system. In addition, the genes coding for metalloprotease and the cell surface layer protein which are both secreted through the Lip system and associated with extracellular lipase production, also contained no base substitution. The strain GE14 carrying a high-copy-number lipA plasmid produced a larger amount of the extracellular lipase than the recombinant strains of 8000 and other mutants also did, indicating that GE14 was not only a lipase-overproducing strain, but also an advantageous host strain for overproducing the lipase by a recombinant DNA technique. These results suggest that the lipase-overproducing mutant GE14 and its recombinant strains are promising candidates for the industrial production of the S. marcescens lipase.

Stability of immobilized candida sp. 99-125 Lipase for biodiesel production

Energy Technology Data Exchange (ETDEWEB)

Lu, J. [Beijing Bioprocess Key Laboratory, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing (China); Bioengineering Department, Zhengzhou University, Zhengzhou (China); Deng, L.; Nie, K.; Wang, F.; Tan, T. [Beijing Bioprocess Key Laboratory, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing (China)

2012-12-15

The stability of the immobilized lipase from Candida sp. 99-125 during biodiesel production was investigated. The lipase was separately incubated in the presence of various reaction components such as soybean oil, oleic acid methyl ester, n-hexane, water, methanol, and glycerol, or the lipase was stored at 60, 80, 100 and 120 C. Thereafter the residual lipase activity was determined by methanolysis reaction. The results showed that the lipase was rather stable in the reaction media, except for methanol and glycerol. The stability study performed in a reciprocal shaker indicated that enzyme desorption from the immobilized lipase mainly contributed to the lipase inactivation in the water system. So the methanol and glycerol contents should be controlled more precisely to avoid lipase inactivation, and the immobilization method should be improved with regard to lipase desorption. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Molecular characterization of a proteolysis-resistant lipase from Bacillus pumilus SG2

Directory of Open Access Journals (Sweden)

R. Sangeetha

2014-06-01

Full Text Available Proteolysis-resistant lipases can be well exploited by industrial processes which employ both lipase and protease as biocatalysts. A proteolysis resistant lipase from Bacillus pumilus SG2 was isolated, purified and characterized earlier. The lipase was resistant to native and commercial proteases. In the present work, we have characterized the lip gene which encodes the proteolysis-resistant lipase from Bacillus pumilus SG2. The parameters and structural details of lipase were analysed. The lip gene consisted of 650 bp. The experimental molecular weight of SG2 lipase was nearly double that of its theoretical molecular weight, thus suggesting the existence of the functional lipase as a covalent dimer. The proteolytic cleavage sites of the lipase would have been made inaccessible by dimerisation, thus rendering the lipase resistant to protease.

Applications of immobilized Thermomyces lanuginosa lipase in interesterification

DEFF Research Database (Denmark)

Yang, Tiankui; Fruekilde, Maj-Britt; Xu, Xuebing

2003-01-01

(RSM). Thermomyces lanuginosa lipase had an activity similar to that of immobilized Rhizomucor miehei lipase (Lipozyme RM IM) in the glycerolysis of sunflower oil, but the former had higher activity at a low reaction temperature (5degreesC). Thermomyces lanuginosa lipase was found to have much lower...... catalytic activity than Lipozyme RM IM in the acidolysis of sunflower oil with caprylic acid. However, the activity of T. lanuginosa lipase was only slightly lower than that of Lipozyme RM IM in the ester-ester exchange between tripalmitin (PPP) and the ethyl esters of EPA and DHA (EE). For this reason...

Altering the activation mechanism in Thermomyces lanuginosus lipase

DEFF Research Database (Denmark)

Skjold-Jørgensen, Jakob; Vind, Jesper; Svendsen, Allan

2014-01-01

It is shown by rational site-directed mutagenesis of the lid region in Thermomyces lanuginosus lipase that it is possible to generate lipase variants with attractive features, e.g., high lipase activity, fast activation at the lipid interface, ability to act on water-soluble substrates......, and enhanced calcium independence. The rational design was based on the lid residue composition in Aspergillus niger ferulic acid esterase (FAEA). Five constructs included lipase variants containing the full FAEA lid, a FAEA-like lid, an intermediate lid of FAEA and TlL character, and the entire lid region...... from Aspergillus terreus lipase (AtL). To investigate an altered activation mechanism for each variant compared to that of TlL, a combination of activity- and spectroscopic-based measurements were applied. The engineered variant with a lid from AtL displayed interfacial activation comparable...

Butyl acetate synthesis using immobilized lipase in calcium alginate beads

International Nuclear Information System (INIS)

Mohd Zulkhairi Abdul Rahim; Lee, Pat M.; Lee, Kong H.

2008-01-01

The esterification reaction of acetic acid and n-butanol using immobilized lipase encapsulated in calcium alginate beads (Lipase - CAB) and in chitosan coated calcium alginate beads (Lipase-CCAB) in n-hexane under mild reaction conditions were studied. Effects of temperature and substrate concentration (acetic acid and n-butanol) using Lipase - CAB, Lipase - CCAB and free lipase on the esterification reaction and their thermal stability towards esterification reaction were investigated. Results of temperature studies showed that the butyl acetate conversion increased with increase of temperature and reached the highest yield of about 70% around 50 degree Celsius for both immobilized systems but the yield of product catalyzed by free enzyme decreased as temperature was increased. Thermal stabilities studies showed that the Lipase-CCAB and Lipase-CAB were stable throughout the temperature range of 30-60 degree Celsius. However, free lipase became less stable at temperatures higher than 50 degree Celsius. The substrates, n-butanol and acetic acid exerted different effects on the esterification reaction and the reaction was favoured by higher acetic acid concentration than butanol. Kinetics parameters, Km and Vmax values for both substrates and the specific activities of the three enzyme system were also determined. The beads morphology was examined using SEM. Batch-wise operational stability studies for both immobilized systems demonstrated that the immobilized lipase performed better in the batch wise reactor system than the continuous bioreactor system and that the immobilized lipase remained active for at least 5 cycles of batch wise esterification reactions. (author)

Gastric lipase: localization of the enzyme in the stomach

International Nuclear Information System (INIS)

DeNigris, S.J.; Hamosh, M.; Hamosh, P.; Kasbekar, D.K.

1986-01-01

Isolated gastric glands prepared from human and rabbit stomach secrete lipase in response to secretagogues. They have investigated the localization of this enzyme in three species (rabbit, baboon, guinea pig). Gastric mucosa was sampled from the cardia (C), fundus-smooth (FS), fundus-ruggae (FR) and the antral area (A). Lipase activity was measured in mucosal homogenates using 3 H-triolein as substrate and is expressed in units (U) = nmols free fatty acid released/min/mg wet weight. The localization of lipase is compared with that of pepsin (measured by hydrolysis of 2% hemoglobin at pH 1.8 and expressed in I.U.). Lipase is localized in a well defined area in the rabbit and is diffusely distributed in both guinea pig and baboon. The distribution of lipase and pepsin containing cells differs in all three species. The cellular origin of gastric lipase remains to be determined

Lipase in milk, curd and cheese

NARCIS (Netherlands)

Geurts, T.J.; Lettink, F.J.; Wouters, J.T.M.

2003-01-01

Presence of lipase in milk, curd, whey and cheese was studied. A small amount of the product was added to a large volume of lipase-free whole milk that had been made sensitive to lipolysis by homogenization. Increase of the acidity of the fat in the mixture, determined after incubation, was

Lipase - Catalyzed glycerolysis of sunflower oil to produce partial glycerides.

Directory of Open Access Journals (Sweden)

Zaher, F. A.

1998-12-01

Full Text Available Partial glycerides were prepared by glycerolysis of sunflower oil in presence of lipase enzyme as catalyst. Six lipases of different origins were used and compared for their catalytic activity. These include Chromobacterium lipase, pancreatic lipase, Rhizopus arrhizus lipase, lyophilized lipase (plant lipase in addition to two lipase preparations derived from Rhizopus japonicas; Lilipase A-10 and Lilipase B-2. Chromobacterium lipase was found to be the most active as glycerolysis catalyst whereas lyophilized lipase; a plant preparation from wheat germ was the least active. The results have also shown that the lipase type affects also the product polarity and hence its field of application as a food emulsifier. Less polar products can be obtained using Chromobacterium lipase whereas the more polar ones using a fungal lipase preparation «Lipase A-10». The product polarity is also influenced by the process temperature but the mode of its effect is different for different lipases.

Se prepararon glicéridos parciales mediante glicerolisis de aceite de girasol en presencia de lipasa como catalizador. Seis lipasas de orígenes diferentes se utilizaron y compararon en función de su actividad catalítica. Estas incluyeron lipasa de Chromobacterium, lipasa pancreática, lipasa de Rhizopus arrhizus, lipasa liofilizada (lipasa vegetal además de dos preparaciones de lipasa derivadas de Rhizopus japonicus: lilipase A-10 y lilipase B-2. Se encontró que la lipasa de Chromobacterium fue la más activa como catalizador en la glicerolisis mientras que la lipasa liofilizada, preparación vegetal a partir de germen de trigo, fue la menos activa. Los resultados mostraron que los tipos de lipasa afectan también a la polaridad de los productos y por tanto a los rendimientos en su aplicación como emulsificantes alimentarios. Los productos menos polares pueden obtenerse usando lipasa de

Physics design of the HL-2A tokamak

International Nuclear Information System (INIS)

Gao Qingdi; Li Fangzhu; Zhang Jinhua; Pan Yudong; Jiao Yiming

2005-10-01

An overview report for the physics design of the HL-2A tokamak is presented. By numerically analyzing the plasma shaping and the vertical instability due to plasma elongation, the requirements for the currents of poloidal magnetic field coils and the control system are put forward. Controlling the plasma profile by using NBI (neutral beam injection) and LHCD (lower hybrid current drive) is investigated, and the high performance modes of operation in HL-2A and modeled and designed. The magnetohydrodynamic instabilities in improved confinement configuration (RS configuration) are studied so as to point out the way of plasma control to perform stationary high performance discharges in HL-2A. In order to offer data for updating the HL-2A divertor, performances of the divertor plasma are simulated. (authors)

Seed lipases: sources, applications and properties - a review

Directory of Open Access Journals (Sweden)

M. Barros

2010-03-01

Full Text Available This paper provides an overview regarding the main aspects of seed lipases, such as the reactions catalyzed, physiological functions, specificities, sources and applications. Lipases are ubiquitous in nature and are produced by several plants, animals and microorganisms. These enzymes exhibit several very interesting features, such as low cost and easy purification, which make their commercial exploitation as industrial enzymes a potentially attractive alternative. The applications of lipases in food, detergents, oils and fats, medicines and fine chemistry, effluent treatment, biodiesel production and in the cellulose pulp industry, as well as the main sources of oilseed and cereal seed lipases, are reviewed.

Hepatic Late Effects of Radio-chemotherapy In Pediatric Hodgkin's Lymphoma [HL

International Nuclear Information System (INIS)

Abaza, A.; EL-Khouly, W.A.

2013-01-01

To identify the hepatic long-term effect of radio-chemotherapy in childhood and adolescence Hodgkin's disease (HD) patients regularly attending the pediatric oncology clinic of National Cancer Institute (NCI), 42 long-term survivors (LTS) were studied, together with 26 newly-diagnosed (ND) HD patients and 28 healthy controls. During 3 years period, all patients subjected to thorough clinical history/ examination. Files of LTS were revised for date of diagnoses, original site(s), stage, histopathological subtypes and dose/ duration of therapy. Clinical examination was done with laying stress on blood pressure, visceromegaly and the presence of lymphadenopathy. Lab investigations included CBC, ESR, bone marrow biopsy, liver function tests and Liver biopsy. Radiodiagnostic studies were done whenever indicated. ESR and anemia were significantly higher in ND patients. Serum alkaline phosphatase enzyme was significantly higher in LTS and ND patients, compared to the controls. Finally, the study documented that there is increased serum alkaline phosphatase enzyme and anemia as a long-term complications of radio-chemotherapy in survivors HD patients. Recommendations regarding the comprehensive follow-up of therapy for HD were discussed. Well-Designed studies are needed to reliably evaluate the prevalence of, and risk factors for, hepatic late adverse effects after antineoplastic treatment for childhood cancer

Hormone-sensitive lipase (HSL) expression and regulation in skeletal muscle

DEFF Research Database (Denmark)

Langfort, J; Ploug, T; Ihlemann, J

1998-01-01

Because the enzymatic regulation of muscle triglyceride metabolism is poorly understood we explored the character and activation of neutral lipase in muscle. Western blotting of isolated rat muscle fibers demonstrated expression of hormone-sensitive lipase (HSL). In incubated soleus muscle...... epinephrine increased neutral lipase activity by beta-adrenergic mechanisms involving cyclic AMP-dependent protein kinase (PKA). The increase was paralleled by an increase in glycogen phosphorylase activity and could be abolished by antiserum against HSL. Electrical stimulation caused a transient increase...... in activity of both neutral lipase and glycogen phosphorylase. The increase in lipase activity during contractions was not influenced by sympathectomy or propranolol. Training diminished the epinephrine induced lipase activation in muscle but enhanced the activation as well as the overall concentration...

HL-LHC updates in Japan

CERN Multimedia

Antonella Del Rosso

2014-01-01

At a recent meeting in Japan, updates on the High Luminosity LHC (HL-LHC) project were presented, including the progress made so far and the deadlines still to be met for the upgraded machine to be operational from 2020.   New magnets made with advanced superconductor Nb3Sn in the framework of the HL-LHC project. These magnets are currently under construction at CERN by the TE-MSC group. The LHC is the world’s most powerful particle accelerator, and in 2015 it will reach yet another new record for the energy of its colliding beams. One key factor of its discovery potential is its ability to produce collisions described in mathematical terms by the parameter known as “luminosity”. In 2025, the HL-LHC project will allow the total number of collisions in the LHC to increase by a factor of 10. The first step in this rich upgrade programme is the delivery of the Preliminary Design Report (PDR), which is also a key milestone of the HiLumi LHC Design Study partly fund...

Structural characterization of MAPLE deposited lipase biofilm

Energy Technology Data Exchange (ETDEWEB)

Aronne, Antonio [Department of Chemical Engineering, Materials and Industrial Production, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Ausanio, Giovanni; Bloisi, Francesco [CNR-SPIN and Department of Physics, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Calabria, Raffaela [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Califano, Valeria, E-mail: v.califano@im.cnr.it [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Fanelli, Esther [Department of Chemical Engineering, Materials and Industrial Production, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Massoli, Patrizio [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Vicari, Luciano R.M. [CNR-SPIN and Department of Physics, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy)

2014-11-30

Highlights: • Lipase from Candida Rugosa was deposited by Matrix Assisted Pulsed Laser Evaporation (MAPLE) on KBr pellets, mica and glass substrate. • The deposited film was characterized morphologically and structurally by optical microscopy, SEM and FTIR analysis. • Results of characterization underlined a phenomenon of aggregation taking place. • The aggregation phenomenon was reversible since lipase showed activity in the transesterification reaction between soybean oil and isopropyl alcohol once detached from the substrate. - Abstract: Lipases (triacylglycerol ester hydrolases) are enzymes used in several industrial applications. Enzymes immobilization can be used to address key issues limiting widespread application at industrial level. Immobilization efficiency is related to the ability to preserve the native conformation of the enzyme. MAPLE (Matrix Assisted Pulsed Laser Evaporation) technique, a laser deposition procedure for treating organic/polymeric/biomaterials, was applied for the deposition of lipase enzyme in an ice matrix, using near infrared laser radiation. Microscopy analysis showed that the deposition occurred in micrometric and submicrometric clusters with a wide size distribution. AFM imaging showed that inter-cluster regions are uniformly covered with smaller aggregates of nanometric size. Fourier transform infrared spectroscopy was used for both recognizing the deposited material and analyzing its secondary structure. Results showed that the protein underwent reversible self-association during the deposition process. Actually, preliminary tests of MAPLE deposited lipase used for soybean oil transesterification with isopropyl alcohol followed by gas chromatography–mass spectrometry gave results consistent with undamaged deposition of lipase.

Lipase or amylase for the diagnosis of acute pancreatitis?

Science.gov (United States)

Ismail, Ola Z; Bhayana, Vipin

2017-12-01

Acute pancreatitis is a rapid onset of inflammation of the pancreas causing mild to severe life threatening conditions [1, 2]. In Canada, acute pancreatitis is the 5th most expensive digestive disease in Canada with a considerable economic burden on the health care system [3]. The diagnosis of acute pancreatitis is usually based on the presence of abdominal pain and elevated levels of serum amylase and/or lipase. Many health care centers use either serum amylase, lipase or both to diagnose acute pancreatitis without considering which one could provide a better diagnostic accuracy. The aim of this review is to investigate whether serum lipase alone is a sufficient biomarker for the diagnosis of acute pancreatitis. We have examined various studies looking at the utilization, sensitivity, specificity and cost associated savings of lipase and amylase in the diagnosis of acute pancreatitis. When comparing different studies, serum lipase offers a higher sensitivity than serum amylase in diagnosing acute pancreatitis. Lipase also offers a larger diagnostic window than amylase since it is elevated for a longer time, thus allowing it to be a useful diagnostic biomarker in early and late stages of acute pancreatitis. Several recent evidence-based guidelines recommend the use of lipase over amylase. Nevertheless, both lipase and amylase alone lack the ability to determine the severity and etiology of acute pancreatitis. The co-ordering of both tests has shown little to no increase in the diagnostic sensitivity and specificity. Thus, unnecessary testing and laboratory expenditures can be reduced by testing lipase alone. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Inhibition of lipases from Chromobacterium viscosum and Rhizopus oryzae by tetrahydrolipstatin.

Science.gov (United States)

Potthoff, A P; Haalck, L; Spener, F

1998-01-15

Tetrahydrolipstatin is known as an inhibitor for pancreatic lipase but not for microbial lipases. In this paper we demonstrate that in the presence of water-insoluble substrates like tributyrin or olive oil, tetrahydrolipstatin inhibits the lipases of Chromobacterium viscosum and Rhizopus oryzae, although with different potency. In contrast to porcine pancreatic lipase, which forms an irreversible and covalent enzyme-inhibitor complex with tetrahydrolipstatin, the inhibition of the microbial lipases is reversible as the inhibitor can be removed from the enzyme-inhibitor complex by solvent extraction. Moreover, after inhibition of Chromobacterium viscosum lipase tetrahydrolipstatin remains chemically unchanged.

Social Cost Benefit Analysis of HL-LHC

CERN Document Server

Bastianin, Andrea

2018-01-01

We present a Social Cost–Benefit Analysis (CBA) of the High Luminosity upgrade of the Large Hadron Collider (HL-LHC), assessing its economic costs and benefits up to 2038. The Net Present Value (NPV) of the HL-LHC project is positive at the end of the observation period. The ratio between incremental benefits and incremental costs of the HL-LHC with respect to continue operating the LHC under normal consolidation (i.e. without high-luminosity upgrade) is slightly over 1.7, meaning that each Swiss Franc invested in the HL-LHC upgrade project pays back approximately 1.7 CHF in societal benefits. Simulations based on 50000 Monte Carlo rounds show that there is a 94% chance to observe a positive NPV (i.e. a quantifiable economic benefit for the society). The attractiveness of CERN for Early Stage Researchers (ESR) is key for a positive CBA result. Given that benefits to ESRs are the single most important societal benefit, CERN should invest more in activities facilitating the transition to the international job...

Effect of coumarins on HL-60 cell differentiation.

Science.gov (United States)

Kawaii, S; Tomono, Y; Katase, E; Ogawa, K; Yano, M

2000-01-01

Twenty-eight coumarins, including 7 furocoumarins, were examined for their activity of induction of terminal differentiation of human promyelocytic leukemia cells (HL-60) by nitro blue tetrazolium (NBT) reducing, nonspecific esterase, specific esterase and phagocytic activities. Esculetin, nordalbergin, 6,7-dihydroxy-4-methylcoumarin and imperatorin had strong activity among the coumarins examined. HL-60 cells treated with these coumarins differentiated into mature monocyte/macrophage. The structure-activity relationship established from the results revealed that 6,7-dihydroxy moiety had an important role in the induction of differentiation of HL-60.

Hepatic lipidosis: Clinical review drawn from collective effort.

Science.gov (United States)

Webb, Craig B

2018-03-01

Practical relevance: Hepatic lipidosis (HL) is the most common form of liver dysfunction in cats. If recognized early and treated appropriately, the prognosis is good; if not, the prognosis is grave. Clinical challenges: Distinguishing HL as idiopathic or secondary is critical since the presence of a concurrent disease affects the therapeutic plan and the prognosis. Despite the unique and severe nature of a cat's response to anorexia and the complexity of the metabolic changes underlying this condition, the clinical acumen and technical ability to effectively diagnose and treat HL are readily available to all small animal practitioners. Patient group: Although many species develop a 'fatty liver', the cat is one of relatively few species that suffer from HL. The classic presentation is that of an overweight cat that stops eating for days to weeks, losing weight in the process. Equipment: Abdominal ultrasound is frequently employed in the diagnostic work-up of an anorectic cat; ultrasonographic findings often support a presumptive diagnosis, provide samples for cytology and, perhaps most importantly, help identify concurrent conditions that must be addressed for therapeutic success. All of the equipment necessary for essential nutritional intervention in an anorectic cat is readily available and easily affordable. Evidence base: The material for this review draws heavily on a relatively large number of original studies, excellent reviews by recognized experts, and informative communication with experienced clinicians, hence the term 'collective effort'.

21 CFR 184.1420 - Lipase enzyme preparation derived from Rhizopus niveus.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Lipase enzyme preparation derived from Rhizopus... GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS § 184.1420 Lipase enzyme preparation derived from Rhizopus niveus. (a) Lipase enzyme preparation contains lipase enzyme (CAS Reg. No...

Production of lipase free of citrinin by Penicillium citrinum.

Science.gov (United States)

Pimentel, M C; Melo, E H; Lima Filho, J L; Durán, N

1996-02-01

Lipase (Glycerol ester hydrolase E.G. 3.1.1.3) from a Brazilian strain of Penicillium citrinum free of the mycotoxin citrinin has been investigated. Citrinin production was inhibited by using culture medium containing olive oil, soybean oil and corn oil as carbon sources. Potassium concentration and pH play an important role in citrinin production. Potassium concentration lower than 30 mM and pH below 4.5 inhibited the mycotoxin production. P. citrinum produced lipase free of extraneous proteins and citrinin when cultured using, as nitrogen source, ammonium sulphate (lipase activity of 7.88 U/mg) and yeast extract (lipase activity of 4.95 U/mg) with olive oil as carbon source. This data is relevant to the larger scale production of lipases for food technology applications, from Penicillium citrinum.

Engineering Lipases: walking the fine line between activity and stability

Science.gov (United States)

Dasetty, Siva; Blenner, Mark A.; Sarupria, Sapna

2017-11-01

Lipases are enzymes that hydrolyze lipids and have several industrial applications. There is a tremendous effort in engineering the activity, specificity and stability of lipases to render them functional in a variety of environmental conditions. In this review, we discuss the recent experimental and simulation studies focused on engineering lipases. Experimentally, mutagenesis studies have demonstrated that the activity, stability, and specificity of lipases can be modulated by mutations. It has been particularly challenging however, to elucidate the underlying mechanisms through which these mutations affect the lipase properties. We summarize results from experiments and molecular simulations highlighting the emerging picture to this end. We end the review with suggestions for future research which underscores the delicate balance of various facets in the lipase that affect their activity and stability necessitating the consideration of the enzyme as a network of interactions.

Up-regulation of hepatic Acyl CoA: Diacylglycerol acyltransferase-1 (DGAT-1) expression in nephrotic syndrome.

Science.gov (United States)

Vaziri, Nosratola D; Kim, Choong H; Phan, Dennis; Kim, Sara; Liang, Kaihui

2004-07-01

Nephrotic syndrome is associated with hypercholesterolemia, hypertriglyceridemia, and marked elevations of plasma low-density lipoprotein (LDL) and very low-density lipoprotein (VLDL). Hypertriglyceridemia in nephrotic syndrome is accompanied by increased hepatic fatty acid synthesis, elevated triglyceride secretion, as well as lipoprotein lipase, VLDL-receptor, and hepatic triglyceride lipase deficiencies, which lead to impaired clearance of triglyceride-rich lipoproteins. Acyl CoA: diacylglycerol acyltransferase (DGAT) is a microsomal enzyme that joins acyl CoA to 1, 2-diacylglycerol to form triglyceride. Two distinct DGATs (DGAT-1 and DGAT2) have recently been identified in the liver and other tissues. The present study tested the hypothesis that the reported increase in hepatic triglyceride secretion in nephrotic syndrome may be caused by up-regulation of DGAT. Male Sprague-Dawley rats were rendered nephrotic by two sequential injections of puromycin aminonucleoside (130 mg/kg on day 1 and 60 mg/kg on day 14) and studied on day 30. Placebo-treated rats served as controls. Hepatic DGAT-1 and DGAT-2 mRNA abundance and enzymatic activity were measured. The nephrotic group exhibited heavy proteinuria, hypoalbuminemia, hypercholesterolemia, hypertriglyceridemia, and marked elevation of VLDL concentration. Hepatic DGAT-1 mRNA, DGAT-1, and total DGAT activity were significantly increased, whereas DGAT-2 mRNA abundance and activity were unchanged in the nephrotic rats compared to the control animals. The functional significance of elevation of DGAT activity was illustrated by the reduction in microsomal free fatty acid concentration in the liver of nephrotic animals. Nephrotic syndrome results in up-regulation of hepatic DGAT-1 expression and activity, which can potentially contribute to the associated hypertriglyceridemia by enhancing triglyceride synthesis. Thus, it appears that both depressed catabolism and increased synthetic capacity contribute to

Study of enzymatic reactors with microencapsulated lipase. Doctoral thesis. Estudo de reactores enzimaticos com lipase microencapsulada

Energy Technology Data Exchange (ETDEWEB)

de Franca Teixeira dos Prazeres, D.M.

1992-10-01

The work reports the development of a membrane reactor for the hydrolysis of triglycerides catalyzed by lipase B from Chromobacterium viscosum in AOT/isooctane reversed miceller system. In a preliminary phase the potential of the organic system was evaluated with comparative studies on the activity and stability of lipase B in aqueous media (emulsion) and in the alternative miceller media. A tubular ceramic membrane reactor with recirculation was selected for the olive oil hydrolysis in a reversed miceller system. The influence of the hydration degree, recirculation rate, AOT, olive oil and lipase concentration in the operation of the reactor were investigated in a batch mode. The hydration degree was identified as a critical parameter due to its influence in the separation process and in the kinetics of the reaction.

Genetics Home Reference: lysosomal acid lipase deficiency

Science.gov (United States)

... lipase deficiency develop multi-organ failure and severe malnutrition and generally do not survive past 1 year. In the later-onset form of lysosomal acid lipase deficiency , signs and symptoms vary and usually begin in mid-childhood, although they can appear anytime up to late ...

Structural studies on lipoprotein lipase

International Nuclear Information System (INIS)

Socorro, L.

1985-01-01

The structure of lipoprotein lipase is not known. The lack of information on its primary sequence has been due to the inability of preparing it in homogeneous and stable form. This research has focused on the structural characterization of lipoprotein lipase. The first approach taken was to develop a purification method using bovine milk and affinity chromatography on heparin-Sepharose. The protein obtained was a heterogeneous peak with the activity shifted towards the trailing edge fractions. These fractions only presented a 55 Kdalton band on polyacrylamide gel electrophoresis. Monoclonal antibodies against this band detected an endogenous, phenyl methane sulfonyl fluoride-sensitive protease responsible for the presence of lower molecular weight fragments. The second approach was to label the lipoprotein lipase with a radioactive, active site, directed probe. After incubation and affinity chromatography a complex [ 3 H]inhibitor enzyme was isolated with a stoichiometry of 1.00 +/- 0.2. The complex was digested with CNBr and the insoluble peptides at low ionic strength (>90% [ 3 H]dpm) were used for further purification. Differential extraction of the [ 3 H]-peptide, digestion with S. aureus V8 protease, and high performance liquid chromatography yielded a hexapeptide with a composition consistent with the consensus sequence of the active site peptides of many serine-esterase. This and the kinetic data imply this being the mechanism of action for lipoprotein lipase

Lipase from a Brazilian strain of Penicillium citrinum.

Science.gov (United States)

Pimentel, M C; Krieger, N; Coelho, L C; Fontana, J O; Melo, E H; Ledingham, W M; Lima Filho, J L

1994-10-01

A lipases (glycerol ester hydrolases E. C. 3.1.1.3) from a brazilian strain of Penicillium citrinum has been investigated. When the microorganism was cultured in the simple medium (1.0% olive oil and 0.5% yeast extract), using olive oil in as carbon source in the inocula, the enzyme extracted showed maximum activity (409 IU/mL). In addition, decrease of yeast extract concentration also reduces the lipase activity. Nevertheless, when yeast extract was replaced by ammonium sulfate, no activity was detected. Purification by precipitation with ammonium sulfate showed best activity in the 40-60% fraction. The optimum temperature for enzyme activity was found in the range of 34-37 degrees C. However, after 30 min at 60 degrees C, the enzyme was completely inactivated. The enzyme showed optimum at pH 8.0. The dried concentrated fraction (after dialysis and lyophilization) maintained its lipase activity at room temperature (28 degrees C) for 8 mo. This result in lipase stability suggests an application of lipases from P. citrinum in detergents and other products that require a high stability at room temperature.

Dependency of water concentration on ethanolysis of trioleoylglycerol by lipases

DEFF Research Database (Denmark)

Piyatheerawong, W.; Iwasaki, Y; Xu, Xuebing

2004-01-01

tested (Rhizomucor miehei lipase, Burkholderia cepacia lipase and Thermomyces lanuginosus lipase) required larger amounts of free water (ca. 7-9 wt.%) for their best performance and exhibited no ethanolysis reaction at low free water concentrations. The CALB's anomalous behavior was also observed...

Bioremediation of cooking oil waste using lipases from wastes.

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Clarissa Hamaio Okino-Delgado

Full Text Available Cooking oil waste leads to well-known environmental impacts and its bioremediation by lipase-based enzymatic activity can minimize the high cytotoxic potential. In addition, they are among the biocatalysts most commercialized worldwide due to the versatility of reactions and substrates. However, although lipases are able to process cooking oil wastes, the products generated from this process do not necessarily become less toxic. Thus, the aim of the current study is to analyze the bioremediation of lipase-catalyzed cooking oil wastes, as well as their effect on the cytotoxicity of both the oil and its waste before and after enzymatic treatment. Thus, assessed the post-frying modification in soybean oil and in its waste, which was caused by hydrolysis reaction catalyzed by commercial and home-made lipases. The presence of lipases in the extracts obtained from orange wastes was identified by zymography. The profile of the fatty acid esters formed after these reactions was detected and quantified through gas chromatography and fatty acids profile compared through multivariate statistical analyses. Finally, the soybean oil and its waste, with and without enzymatic treatment, were assessed for toxicity in cytotoxicity assays conducted in vitro using fibroblast cell culture. The soybean oil wastes treated with core and frit lipases through transesterification reaction were less toxic than the untreated oils, thus confirming that cooking oil wastes can be bioremediated using orange lipases.

Screening of thermophilic neutral lipase-producing Pseudomonas ...

African Journals Online (AJOL)

From oil-contaminated soil, three lipase-producing microorganisms were selected as good lipase producers using rhodamine B-olive oil plate agar and they were identified as from Pseudomonas, Burkholderia and Klebsiella genera by morphology, biochemical characterization and 16S rRNA gene sequencing. Among the ...

Frozen Microemulsions for MAPLE Immobilization of Lipase

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Valeria Califano

2017-12-01

Full Text Available Candida rugosa lipase (CRL was deposited by matrix assisted pulsed laser evaporation (MAPLE in order to immobilize the enzyme with a preserved native conformation, which ensures its catalytic functionality. For this purpose, the composition of the MAPLE target was optimized by adding the oil phase pentane to a water solution of the amino acid 3-(3,4-dihydroxyphenyl-2-methyl-l-alanine (m-DOPA, giving a target formed by a frozen water-lipase-pentane microemulsion. Fourier transform infrared (FTIR spectroscopy and atomic force microscopy (AFM were used to investigate the structure of MAPLE deposited lipase films. FTIR deconvolution of amide I band indicated a reduction of unfolding and aggregation, i.e., a better preserved lipase secondary structure in the sample deposited from the frozen microemulsion target. AFM images highlighted the absence of big aggregates on the surface of the sample. The functionality of the immobilized enzyme to promote transesterification was determined by thin layer chromatography, resulting in a modified specificity.

Microbial lipases: Production, properties and biotechnological applications

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Josana Maria Messias

2011-09-01

Full Text Available Lipases belong to the group of hydrolases that catalyze the hydrolysis of triacylglycerol lipids to free fatty acids and glycerol. They have significant potential biotechnological applications in catalyzing organic synthesis reactions in non-aqueous solvents using simplified procedures resulting in conversions of high yields. Lipase production has conventionally been performed by submerged fermentation; however, solid-state fermentation processes have been prominent when residues are used as substrates because they serve as low-cost nutrient sources. Microbial lipases can be used as additives in foods to modify and enhance organoleptic properties, as well as in detergents to hydrolyse fats in the treatment of oily effluents, and also have value for pharmaceutical, cosmetic, agrochemical, and oil chemical industries. More recently, they are used in transesterification reactions to convert plant seed oils into biodiesel. The objective of this work was to review the published literature on the production, properties and applications of microbial lipases, and its biotechnological role in producing biodiesel.

Structure of product-bound SMG1 lipase: active site gating implications.

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Guo, Shaohua; Xu, Jinxin; Pavlidis, Ioannis V; Lan, Dongming; Bornscheuer, Uwe T; Liu, Jinsong; Wang, Yonghua

2015-12-01

Monoacylglycerol and diacylglycerol lipases are industrially interesting enzymes, due to the health benefits that arise from the consumption of diglycerides compared to the traditional triglyceride oils. Most lipases possess an α-helix (lid) directly over the catalytic pocket which regulates the activity of the enzyme. Generally, lipases exist in active and inactive conformations, depending on the positioning of this lid subdomain. However, lipase SMG1, a monoacylglycerol and diacylglycerol specific lipase, has an atypical activation mechanism. In the present study we were able to prove by crystallography, in silico analysis and activity tests that only two positions, residues 102 and 278, are responsible for a gating mechanism that regulates the active and inactive states of the lipase, and that no significant structural changes take place during activation except for oxyanion hole formation. The elucidation of the gating effect provided data enabling the rational design of improved lipases with 6-fold increase in the hydrolytic activity toward diacylglycerols, just by providing additional substrate stabilization with a single mutation (F278N or F278T). Due to the conservation of F278 among the monoacylglycerol and diacylglycerol lipases in the Rhizomucor miehei lipase-like family, the gating mechanism described herein might represent a general mechanism applicable to other monoacylglycerol and diacylglycerol lipases as well. Database: Structural data are available in the Protein Data Bank under the accession numbers 4ZRE (F278D mutant) and 4ZRD (F278N mutant). © 2015 FEBS.

Karakterisasi ekstrak kasar lipase Rhizopus stolonifer UICC 137

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Sri Sumiarsih

2001-12-01

Full Text Available There is an increasing commercial interest in enzymatic production of biologically active component, because there are a number of well-known advantages compared to chemical synthesis. One of the most valuable synthetic features of enzyme is their ability to discriminate between enantiomers of racemic substrates. Lipase have become of great interest to the chemical industries wing their usefulness in both hydrolytic and synthesis reactions. The aim of this work was to study the production of lipase by Rhizopus stolonifer UICC 137, and determine the crude lipase preparation characteristics. The lipolytic activity was determined by titrimetric method toward oil-arabic gum emultion as a substrate. The strain produced lipase at appreciable lipolytic when cultivated for 72 hours in medium containing 3% glucose and 1% olive oil. Our data suggest that the strain produced lipase since the exponential phase of its growth. Lipase with optimum lipolytic activity was obtained at late stationary phase. The optimum condition for lipolytic activity measurement were pH of 7.5 and temperature 37oC, the crude enzyme had a specific activity 20.2 unit/ mg protein, the Vmax was 15.1 mol/ min and KM was 12.5 mg/ ml. The crude enzyme retained 79.9%, 68.0% and 52.6% of its lipolytic activity, when incubated for 90 minutes at temperature of 40, 50, and 60oC respectively.

The specificity of Several Kinds Lipases on n-3 Polyunsaturated Fatty Acids

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Jenny Elisabeth, T Yuliani, P M Tambunan, J M Purba

2001-04-01

Full Text Available Several lipases from microbial and plant, i.e Rhizomucor miehei, Pseudomonas sp., Candida antartica, rice bran, and Carica papaya latex (CPL were examined for synthesis of omega-3 (n-3 PUFA-rich glyceride by hydrolysis and acidolysis reaction. Tuna oil was used in hydrolysis reaction, whereas tuna and palm oils were used as source of triglyceride (TAG molecules and n-3 PUFA concentrate from tuna oil as source of EPA and DHA in acidolysis reaction.For hydrolysis reaction, the rice bran and CPL lipases showed the lowest hydrolytic activity of the tuna oil, whereas the R. miehei lipase showed the highest hydrolytic activity but was unable to hydrolyze EPA and DHA. On the contrary, the C. antartica and Pseudomonas sp. lipases acted stronger on hydrolysis of DHA ester bond than EPA.For acidolysis reaction, all the lipases showed ability to incorporate n-3 PUFA into tuna and palm oils. C. antartica lipase had the maximum DHA incorporation into tuna and palm oils, rice bran lipase had relatively similar ability with R. miehei lipase, and the CPL lipase had the lowest ability. This study proved that rice bran and CPL lipases also had transesterification activity and showed the feasibility of the rice bran lipase to be a biocatalyst for n-3 PUFA-rich glyceride production. Increasing the substrate ratio, of n-3 PUFA concentrate and tuna or palm oil, could increase the EPA and DHA incorporation. The R. miehei, rice bran, and CPL lipases unabled to incorporate DHA into DHA-containing glyceride molecule, whereas C. antartica lipase had the capability in high ratio of n-3 PUFA concentrate to oil. Therefore, the lipases were easier to incorporate n-3 PUFA into palm oil than tuna oil, since the TAG molecules of palm oil was not as complex as tuna oil. It could be suggested that the lipases did not only have acyl chain and positional specificity, but also the whole glyceride structure specificity.

Mutation induced enhanced biosynthesis of lipase | Bapiraju ...

African Journals Online (AJOL)

The purpose of the present investigation is to enhance production of biomedically important enzyme lipase by subjecting the indigenous lipase producing strain Rhizopus sp. BTS-24 to improvement by natural selection and random mutagenesis (UV and N-methyl-N'-nitro-N-nitroso guanidine, NTG). The isolation of mutants ...

Lipase and esterase: to what extent can this classification be applied accurately?

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Danielle Branta Lopes

2011-09-01

Full Text Available Enzyme technology is an ever-growing field of knowledge and, in recent years, this technology has raised renewed interest, due to the search for new paradigms in several productive processes. Lipases, esterases and cutinases are enzymes used in a wide range of processes involving synthesis and hydrolysis reactions. The objective of this work was to investigate and compare the specific lipase and esterase activities of five enzymes - four already classified as lipases and one classified as cutinase - in the presence of natural and synthetic substrates. All tested enzymes presented both esterase and lipase specific activities. The highest specific esterase activity was observed for Aspergillus 1068 lipase in natural substrate and for F. oxysporum cutinase in synthetic substrate, while the highest specific lipase activity was observed for Geotrichum sp. lipase in natural substrate and for F. oxysporum cutinase in synthetic substrate. These results display some interface-independent lipolytic activity for all lipases tested. This is in accordance with the rationale that a new and broader definition of lipases may be necessary.

Lipase inactivation in wheat germ by gamma irradiation

International Nuclear Information System (INIS)

Jha, Pankaj Kumar; Kudachikar, V.B.; Kumar, Sourav

2013-01-01

An attempt was made to improve the shelf life of wheat germ by optimizing processing conditions involving γ-irradiation. Studies were carried out to investigate the effect of γ-irradiation (0–30 kGy doses) on the chemical composition of wheat germ with respect to variation in moisture, total ash, crude fat, free fatty acid, protein and lipase activity. The results demonstrate that shelf stability of wheat germ was achieved by inactivation of lipase at doses of γ-irradiation greater than 12 kGy. - Highlights: Ø γ-irradiation was found to inactivate Lipase present in Wheat Germ. Ø The treatment did not result in significant changes in Total Ash, Moisture and Protein Content of Wheat Germ. Ø The irradiation at 30 kGy resulted in 31.2 % inactivation of Lipase in Wheat Germ

Optics Measurements and Correction Challenges for the HL-LHC

CERN Document Server

Carlier, Felix Simon; Fartoukh, Stephane; Fol, Elena; Gamba, Davide; Garcia-Tabares Valdivieso, Ana; Giovannozzi, Massimo; Hofer, Michael; Langner, Andy Sven; Maclean, Ewen Hamish; Malina, Lukas; Medina Medrano, Luis Eduardo; Persson, Tobias Hakan Bjorn; Skowronski, Piotr Krzysztof; Tomas Garcia, Rogelio; Van Der Veken, Frederik; Wegscheider, Andreas

2017-01-01

Optics control in the HL-LHC will be challenged by a very small β* of 15 cm in the two main experiments. HL-LHC physics fills will keep a constant luminosity during several hours via β* leveling. This will require the commissioning of a large number of optical configurations, further challenging the efficiency of the optics measurements and correction tools. We report on the achieved level of optics control in the LHC with simulations and extrapolations for the HL-LHC.

Acridones as inducers of HL-60 cell differentiation.

Science.gov (United States)

Kawaii, S; Tomono, Y; Katase, E; Ogawa, K; Yano, M; Takemura, Y; Ju-ichi, M; Ito, C; Furukawa, H

1999-03-01

Fifteen acridone alkaloids were examined for their activity of induction of human promyelocytic leukemia cell (HL-60) differentiation. HL-60 cells were differentiated into mature monocyte/macrophage by atalaphyllidine (9), atalaphyllinine (12), and des-N-methylnoracronycine (13). The activities of NBT reduction, nonspecific esterase, and phagocytosis, were induced by 2.5 microM of 9, 12, and 13. After a 4-day treatment, 9, 12, and 13 at 10 microM inhibited clonal proliferation of HL-60 cells by 28, 96, and 63%, respectively. The structure-activity relationship established from the results revealed that hydroxyl group at C-1 and prenyl group at C-2 had an important role.

Production of Cold Active Lipase from Bacillus sp.

OpenAIRE

Yasemin, Sara; Arabacı, Nihan; Korkmaz Güvenmez, Hatice

2018-01-01

A cold active lipase producing Bacillus sp. strains were isolated from sewage of oil. Bacillus sp. strain SY-7 was determined as the best lipase producing isolate. The highest enzyme production was found at 20°C and pH 8.0 on tributyrin media. Analyses of molecular mass of the partial purified lipase was carried out by SDS-PAGE which revealed a single band as 110.5 kDa. The enzyme activity and stability were determined by spectrophotometric and titrimetric methods. The enzyme was active betwe...

Zymography Detection of a Bacterial Extracellular Thermoalkaline Esterase/Lipase Activity.

Science.gov (United States)

Tapizquent, María; Fernández, Marleny; Barreto, Georgina; Hernández, Zully; Contreras, Lellys M; Kurz, Liliana; Wilkesman, Jeff

2017-01-01

Lipases are esterases that occur widely in nature, yet those with commercial relevance are exclusively from microbial origin. Glycerol and long-chain fatty acids are the products after hydrolysis of esters bonds in saponifiable lipids catalyzed by lipases. In this work, we describe lipase/esterase activity contained in cell-free fractions from thermophilic bacteria, cultured in medium containing olive oil. Analysis of the cell-free fractions by electrotransference zymography, using tributyrin as substrate, revealed bands corresponding to lipase activity. The method is simple, fast, and inexpensive.

Purification and characterization of a new cold active lipase, EnL A ...

African Journals Online (AJOL)

Search of lipase engineering data base (LED) revealed that this protein belongs to a newly introduced super family of Candida antarctica lipase A like and to the homologous family of Aspergillus lipase like. Key words: Cold active lipase, Emericella nidulans, hydrophobic interaction chromatography, Candida antarctica ...

Realm of Thermoalkaline Lipases in Bioprocess Commodities

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Ahmad Firdaus B. Lajis

2018-01-01

Full Text Available For decades, microbial lipases are notably used as biocatalysts and efficiently catalyze various processes in many important industries. Biocatalysts are less corrosive to industrial equipment and due to their substrate specificity and regioselectivity they produced less harmful waste which promotes environmental sustainability. At present, thermostable and alkaline tolerant lipases have gained enormous interest as biocatalyst due to their stability and robustness under high temperature and alkaline environment operation. Several characteristics of the thermostable and alkaline tolerant lipases are discussed. Their molecular weight and resistance towards a range of temperature, pH, metal, and surfactants are compared. Their industrial applications in biodiesel, biodetergents, biodegreasing, and other types of bioconversions are also described. This review also discusses the advance of fermentation process for thermostable and alkaline tolerant lipases production focusing on the process development in microorganism selection and strain improvement, culture medium optimization via several optimization techniques (i.e., one-factor-at-a-time, surface response methodology, and artificial neural network, and other fermentation parameters (i.e., inoculums size, temperature, pH, agitation rate, dissolved oxygen tension (DOT, and aeration rate. Two common fermentation techniques for thermostable and alkaline tolerant lipases production which are solid-state and submerged fermentation methods are compared and discussed. Recent optimization approaches using evolutionary algorithms (i.e., Genetic Algorithm, Differential Evolution, and Particle Swarm Optimization are also highlighted in this article.

Realm of Thermoalkaline Lipases in Bioprocess Commodities.

Science.gov (United States)

Lajis, Ahmad Firdaus B

2018-01-01

For decades, microbial lipases are notably used as biocatalysts and efficiently catalyze various processes in many important industries. Biocatalysts are less corrosive to industrial equipment and due to their substrate specificity and regioselectivity they produced less harmful waste which promotes environmental sustainability. At present, thermostable and alkaline tolerant lipases have gained enormous interest as biocatalyst due to their stability and robustness under high temperature and alkaline environment operation. Several characteristics of the thermostable and alkaline tolerant lipases are discussed. Their molecular weight and resistance towards a range of temperature, pH, metal, and surfactants are compared. Their industrial applications in biodiesel, biodetergents, biodegreasing, and other types of bioconversions are also described. This review also discusses the advance of fermentation process for thermostable and alkaline tolerant lipases production focusing on the process development in microorganism selection and strain improvement, culture medium optimization via several optimization techniques (i.e., one-factor-at-a-time, surface response methodology, and artificial neural network), and other fermentation parameters (i.e., inoculums size, temperature, pH, agitation rate, dissolved oxygen tension (DOT), and aeration rate). Two common fermentation techniques for thermostable and alkaline tolerant lipases production which are solid-state and submerged fermentation methods are compared and discussed. Recent optimization approaches using evolutionary algorithms (i.e., Genetic Algorithm, Differential Evolution, and Particle Swarm Optimization) are also highlighted in this article.

Liver lipase and high-density lipoprotein. Lipoprotein changes after incubation of human serum with rat liver lipase.

Science.gov (United States)

Groot, P H; Scheek, L M; Jansen, H

1983-05-16

Human sera were incubated with rat liver lipase after inactivation of lecithin:cholesterol acyltransferase, and the changes in serum lipoprotein composition were measured. In the presence of liver lipase serum triacylglycerol and phosphatidylcholine were hydrolyzed. The main changes in the concentrations of these lipids were found in the high-density lipoprotein fraction. Subfractionation of high-density lipoprotein by rate-zonal ultracentrifugation showed a prominent decrease in all constituents of high-density lipoprotein2, a smaller decrease in the 'light' high-density lipoprotein3 and an increase in the 'heavy' high-density lipoprotein3. These data support a concept in which liver lipase is involved in high-density lipoprotein2 phospholipid and triacylglycerol catabolism and suggest that as a result of this action high-density lipoprotein2 is converted into high-density lipoprotein3.

21 CFR 173.140 - Esterase-lipase derived from Mucor miehei.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Esterase-lipase derived from Mucor miehei. 173.140... HUMAN CONSUMPTION Enzyme Preparations and Microorganisms § 173.140 Esterase-lipase derived from Mucor miehei. Esterase-lipase enzyme, consisting of enzyme derived from Mucor miehei var. Cooney et Emerson by...

Beneficial effects of adding lipase enzyme to broiler diet

International Nuclear Information System (INIS)

Elbarkouky, E.M.A.

2005-01-01

A total number of 300 Ross broiler chicks were obtained from commercial hatchery at one day of age. The chicks were divided into three groups (50 males and 50 females in each). The first and second groups were supplemented with 3000 and 2000 lU/kg diet of lipase enzyme, respectively, while the third group served as control and fed on basal diet. Birds fed on diets that supplemented with lipase enzyme showed significant increase in body weight and dry matter intake, as well as fats and protein content dry matters. The serum lipase activity showed significant increase in treated groups compared to the control. Non-significant changes were determined in serum total lipids, T3, T4 and ash content. Birds supplemented with lipase showed significant decrease in cholesterol concentration. It could be concluded that birds fed diets containing 2000 or 3000 lU/kg diet of lipase enzyme exhibited improvement in broiler performance

Anti- and pro-lipase activity of selected medicinal, herbal and aquatic plants, and structure elucidation of an anti-lipase compound.

Science.gov (United States)

Ado, Muhammad Abubakar; Abas, Faridah; Mohammed, Abdulkarim Sabo; Ghazali, Hasanah M

2013-11-26

Plants that help in slowing down the digestion of triacylglycerols (TAGs) in the pancreas and small intestine of humans play an important role in the reduction of obesity. On the other hand, there may be plants or plant parts that stimulate intestinal lipolytic activity, thus contributing to greater TAG assimilation. The aim of this study was to evaluate the aqueous methanolic extracts of ninety eight (98) medicinal, herbal and aquatic plant materials from Malaysia for their effect on porcine pancreatic lipase (PPL) activity and to identify the structure of an anti-lipase compound from one of the sources. The degree of inhibition was also quantified as relative to orlistat activity against PPL (orlistat equivalents). Results revealed that while 19.4% of the extracts were found to have anti-lipase activity ≥80%, 12% were actually found to promote PPL activity. Twenty two percent (22.4%) exhibited moderate inhibition (41%-80%) and 2% were neutral toward PPL activity. The ripe fruit of Averrhoa carambola and the leaves of Archidendron jiringa (Jack) I.C Nielsen L. (jering), Cynometra cauliflora (nam-nam) and Aleurites moluccana (L.) Willd (candle nut/buah keras) had the highest (100%) anti-lipase activity and are equivalent to 0.11 µg orlistat/mL. Plants that stimulated lipase activity included Pimpinella anisum L. (aniseed/jintan manis), activating the enzyme by 186.5%. Kaempferol 3-O-rhamnoside was isolated from the ethyl acetate fraction of C. cauliflora leaves and found to be an active lipase inhibitor. The structure was elucidated using 1H-NMR, 13C-NMR and 2D-NMR analyses.

ENZYMATIC BIODIESEL SYNTHESIS FROM ACID OIL USING A LIPASE MIXTURE

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Kelly C. N. R. Pedro

Full Text Available The conventional biodiesel production process has some disadvantages. It is necessary to use refined vegetable oils with low free fatty acids (FFAs content. An alternative route is to use low-cost acid oils in an enzymatic process. The use of lipases allows simultaneous esterification of FFAs and transesterification of triglycerides present in raw material forming alkyl esters. The aim of this work was to study the production of biodiesel using soybean oils with different acid contents (Acid Value of 8.5, 50, 90 and ethanol catalyzed by commercial immobilized lipases (Novozym 435, Lipozyme RM IM and Lipozyme TL IM. A significant decrease of acid value was observed mainly with Novozym 435 and Lipozyme RM IM. The use of a mixture of two immobilized lipases was also investigated to decrease catalyst cost and increase the amount of ester produced. The three commercial immobilized lipases were mixed in a dual system and tested for biodiesel synthesis from acid oil (AV of 8.5, 50 and 90. A positive synergistic effect occurred mainly for Lipozyme TL IM (1,3-specific lipase and Novozym 435 (non-specific lipase blend. The ester content doubled when this lipase mixture was used in ethanolysis of acid oil with AV of 90.

Fast crab cavity failures in HL-LHC

CERN Document Server

Yee-Rendon, B; Calaga, R; Tomas, R; Zimmermann, F; Barranco, J

2014-01-01

Crab cavities (CCs) are a key ingredient of the High-Luminosity Large Hadron Collider (HL-LHC) to ensure head on collisions at the main experiments (ATLAS and CMS) and fully profit from the smaller provided by the ATS optics [1]. At KEKB, CCs have exhibited abrupt changes of phase and voltage during a time period of few LHC turns and considering the large energy stored in the HL-LHC beam, CC failures represent a serious risk to the LHC machine protection. In this paper, we discuss the effect of CC voltage or phase changes on a time interval similar to, or longer than, the one needed to dump the beam. The simulations assume a realistic steady-state distribution to assess the beam losses for the HL-LHC. Additionally, some strategies are studied in order to reduce the damage caused by the CC failures.

Biotechnological applications of halophilic lipases and thioesterases.

Science.gov (United States)

Schreck, Steven D; Grunden, Amy M

2014-02-01

Lipases and esterases are enzymes which hydrolyze ester bonds between a fatty acid moiety and an esterified conjugate, such as a glycerol or phosphate. These enzymes have a wide spectrum of use in industrial applications where their high activity, broad substrate specificity, and stability under harsh conditions have made them integral in biofuel production, textile processing, waste treatment, and as detergent additives. To date, these industrial applications have mainly leveraged enzymes from mesophilic and thermophilic organisms. However, increasingly, attention has turned to halophilic enzymes as catalysts in environments where high salt stability is desired. This review provides a brief overview of lipases and esterases and examines specific structural motifs and evolutionary adaptations of halophilic lipases. Finally, we examine the state of research involving these enzymes and provide an in-depth look at an exciting algal-based biofuel production system. This system uses a recombinant halophilic lipase to increase oil production efficiency by cleaving algal fatty acids from the acyl carrier protein, which eliminates feedback inhibition of fatty acid synthesis.

Immobilization of Isolated Lipase From Moldy Copra (Aspergillus Oryzae)

OpenAIRE

Dali, Seniwati; Patong, A. B. D. Rauf; Jalaluddin, M. Noor; Pirman; Hamzah, Baharuddin

2011-01-01

Enzyme immobilization is a recovery technique that has been studied in several years, using support as a media to help enzyme dissolutions to the reaction substrate. Immobilization method used in this study was adsorption method, using specific lipase from Aspergillus oryzae. Lipase was partially purified from the culture supernatant of Aspergillus oryzae. Enzyme was immobilized by adsorbed on silica gel. Studies on free and immobilized lipase systems for determination of optimum pH, optimum ...

KARAKTERISASI SIFAT-SIFAT BIOKIMIA EKSTRAK KASAR LIPASE EKSTRASELULER BAKTERI Azospirillum sp.PRD1

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Santi Nur Handayani

2011-11-01

Full Text Available Enzim lipase mempunyai peranan penting dalam katalis berbagai reaksi industri satu diantaranya pembuatan flavor melalui reaksi esterifikasi. Lipase adalah biokatalis yang berperan besar dalam aplikasi bioteknologi, seperti dalam sintesis biopolimer, biodiesel, produksi obat, dan produksi flavor. Peningkatan penggunaan lipase untuk industri mendorong dilakukan penelitian untuk mendapatkan sumber-sumber lipase baru. Sumber lipase yang potensial salah satunya adalah bakteri Azospirillum sp.PRD1 dari isolat lokal Laboratorium Mikrobiologi, Fakultas Biologi Universitas Jenderal Soedirman. Tujuan penelitian adalah untuk mendapatkan ekstrak kasar lipase dan menentukan karakteristik sifat-sifat biokimiawinya. Metode yang digunakan antara lain peremajaan bakteri Azospirillum sp.PRD1, dan produksi inokulum, penentuan waktu produksi optimum dan fase pertumbuhan bakteri, ekstraksi dan produksi ekstrak kasar lipase dan penentuan karakteristik sifat-sifat biokimiawinya. Hasil penelitian diperoleh ekstrak kasar lipase dari inokulum berumur 7 jam dan medium produksi dengan induser minyak zaitun yang diinkubasi selama 3 jam memiliki aktivitas spesifik 7,0547 Unit/mg. Lipase ekstrak kasar optimum pada pH 7, suhu 40 oC dan waktu inkubasi selama 25 menit. Lipase merupakan metaloenzim dengan kofaktor Zn2+ , Mn2+, Hg2+, Ca2+, Co2+ and Mg2+.

Elevated Levels of Endocannabinoids in Chronic Hepatitis C May Modulate Cellular Immune Response and Hepatic Stellate Cell Activation

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Eleonora Patsenker

2015-03-01

Full Text Available The endocannabinoid (EC system is implicated in many chronic liver diseases, including hepatitis C viral (HCV infection. Cannabis consumption is associated with fibrosis progression in patients with chronic hepatitis C (CHC, however, the role of ECs in the development of CHC has never been explored. To study this question, anandamide (AEA and 2-arachidonoyl glycerol (2-AG were quantified in samples of HCV patients and healthy controls by gas and liquid chromatography mass spectrometry. Fatty acid amide hydrolase (FAAH and monoaclyglycerol lipase (MAGL activity was assessed by [3H]AEA and [3H]2-AG hydrolysis, respectively. Gene expression and cytokine release were assayed by TaqMan PCR and ELISpot, respectively. AEA and 2-AG levels were increased in plasma of HCV patients, but not in liver tissues. Hepatic FAAH and MAGL activity was not changed. In peripheral blood mononuclear cells (PBMC, ECs inhibited IFN-γ, TNF-α, and IL-2 secretion. Inhibition of IL-2 by endogenous AEA was stronger in PBMC from HCV patients. In hepatocytes, 2-AG induced the expression of IL-6, -17A, -32 and COX-2, and enhanced activation of hepatic stellate cells (HSC co-cultivated with PBMC from subjects with CHC. In conclusion, ECs are increased in plasma of patients with CHC and might reveal immunosuppressive and profibrogenic effects.

Yeast Kluyveromyces lactis as host for expression of the bacterial lipase: cloning and adaptation of the new lipase gene from Serratia sp.

Science.gov (United States)

Šiekštelė, Rimantas; Veteikytė, Aušra; Tvaska, Bronius; Matijošytė, Inga

2015-10-01

Many microbial lipases have been successfully expressed in yeasts, but not in industrially attractive Kluyveromyces lactis, which among other benefits can be cultivated on a medium supplemented with whey--cheap and easily available industrial waste. A new bacterial lipase from Serratia sp. was isolated and for the first time expressed into the yeast Kluyveromyces lactis by heterologous protein expression system based on a strong promoter of Kluyveromyces marxianus triosephosphate isomerase gene and signal peptide of Kluyveromyces marxianus endopolygalacturonase gene. In addition, the bacterial lipase gene was synthesized de novo by taking into account a codon usage bias optimal for K. lactis and was expressed into the yeast K. lactis also. Both resulting strains were characterized by high output level of the target protein secreted extracellularly. Secreted lipases were characterized for activity and stability.

Anti- and Pro-Lipase Activity of Selected Medicinal, Herbal and Aquatic Plants, and Structure Elucidation of an Anti-Lipase Compound

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Muhammad Abubakar Ado

2013-11-01

Full Text Available Plants that help in slowing down the digestion of triacylglycerols (TAGs in the pancreas and small intestine of humans play an important role in the reduction of obesity. On the other hand, there may be plants or plant parts that stimulate intestinal lipolytic activity, thus contributing to greater TAG assimilation. The aim of this study was to evaluate the aqueous methanolic extracts of ninety eight (98 medicinal, herbal and aquatic plant materials from Malaysia for their effect on porcine pancreatic lipase (PPL activity and to identify the structure of an anti-lipase compound from one of the sources. The degree of inhibition was also quantified as relative to orlistat activity against PPL (orlistat equivalents. Results revealed that while 19.4% of the extracts were found to have anti-lipase activity ≥80%, 12% were actually found to promote PPL activity. Twenty two percent (22.4% exhibited moderate inhibition (41%–80% and 2% were neutral toward PPL activity. The ripe fruit of Averrhoa carambola and the leaves of Archidendron jiringa (Jack I.C Nielsen L. (jering, Cynometra cauliflora (nam-nam and Aleurites moluccana (L. Willd (candle nut/buah keras had the highest (100% anti-lipase activity and are equivalent to 0.11 µg orlistat/mL. Plants that stimulated lipase activity included Pimpinella anisum L. (aniseed/jintan manis, activating the enzyme by 186.5%. Kaempferol 3-O-rhamnoside was isolated from the ethyl acetate fraction of C. cauliflora leaves and found to be an active lipase inhibitor. The structure was elucidated using 1H-NMR, 13C-NMR and 2D-NMR analyses.

Serum Lipase as Clinical Laboratory Index for Chronic Renal Failure Diagnosis.

Science.gov (United States)

Zhu, Ying; Dong, Jing; Wang, Ping; Huang, Huifang; Jin, Xiaohua; Zhou, Jingou; Shi, Jingfang; Gu, Guohao; Chen, Jun; Xu, Jun; Song, Yanhui

2016-07-01

Measuring the level of serum lipase has been used for the clinical diagnosis of acute pancreatitis. Reports showed that the serum lipase level increased in patients of clinical renal failure. In this study, we aimed to measure the change of serum lipase levels in chronic kidney diseases and determine whether it could serve as a clinical laboratory index for clinical renal failure diagnosis. Materials: The OLYMPUS AU5400 automatic biochemical analyzer was used to determine the serum levels of lipase and creatinine. The study included 120 cases in the clinical renal failure group, 76 cases in the nephrotic syndrome group, 81 cases in the chronic nephritis group, and 80 healthy controls from our hospital volunteers in the same period. We then compared the lipase levels and conducted statistical analyses among these groups. The serum lipase levels were 15.3 U/L, 79.8 U/L, 45.1 U/L, and 51.0 U/L in the normal control, clinical renal failure, nephrotic syndrome, and chronic nephritis groups, respectively. The lipase levels in the groups with diseases were significantly different compared with that of the normal control group (p renal failure group was significantly higher than that of the nephrotic syndrome group and chronic nephritis group (p chronic nephritis group (p > 0.05) was observed. Moreover, an association of the serum lipase with disease progression was observed in the study. Serum lipase is an effective serological index which can reflect the clinical changes in the clinical renal failure and tends to increase through the progression of renal dysfunction.

Enhancement of lipase catalyzed-fatty acid methyl esters production from waste activated bleaching earth by nullification of lipase inhibitors.

Science.gov (United States)

Dwiarti, Lies; Ali, Ehsan; Park, Enoch Y

2010-01-01

This study sought to identify inhibitory factors of lipase catalyzed-fatty acid methyl esters (FAME) production from waste activated bleaching earth (wABE). During the vegetable oil refinery process, activated bleaching earth (ABE) is used for removing the impure compounds, but adsorbs vegetable oil up to 35-40% as on a weight basis, and then the wABE is discarded as waste material. The impurities were extracted from the wABE with methanol and evaluated by infra-red (IR) spectroscopy, which revealed that some were chlorophyll-plant pigments. The chlorophylls inhibited the lipase during FAME conversion from wABE. The inhibition by a mixture of chlorophyll a and b was found to be competitive. The inhibition of the enzymatic hydrolysis of waste vegetable oil contained in wABE by chlorophyll a alone was competitive, while the inhibition by chlorophyll b alone was non-competitive. Furthermore, the addition of a small amount of alkali nullified this inhibitory effect and accelerated the FAME production rate. When 0.9% KOH (w/w wABE) was added to the transesterification reaction with only 0.05% lipase (w/w wABE), the maximum FAME production rate improved 120-fold, as compared to that without the addition of KOH. The alkali-combined lipase significantly enhanced the FAME production rate from wABE, in spite of the presence of the plant pigments, and even when a lower amount of lipase was used as a catalyst.

Lipase catalyzed ester synthesis for food processing industries

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Aravindan Rajendran

2009-02-01

Full Text Available Lipases are one of the most important industrial biocatalyst which catalyzes the hydrolysis of lipids. It can also reverse the reaction at minimum water activity. Because of this pliable nature, it is widely exploited to catalyze the diverse bioconversion reactions, such as hydrolysis, esterification, interesterification, alcoholysis, acidolysis and aminolysis. The property to synthesize the esters from the fatty acids and glycerol promotes its use in various ester synthesis. The esters synthesized by lipase finds applications in numerous fields such as biodiesel production, resolution of the recemic drugs, fat and lipid modification, flavour synthesis, synthesis of enantiopure pharmaceuticals and nutraceuticals. It plays a crucial role in the food processing industries since the process is unaffected by the unwanted side products. Lipase modifications such as the surfactant coating, molecular imprinting to suit for the non-aqueous ester synthesis have also been reported. This review deals with lipase catalyzed ester synthesis, esterification strategies, optimum conditions and their applications in food processing industries.Lipases são catalizadores industriais dos mais importantes, os quais catalizam a hidrólise de lipídeos. Também podem reverter a reação a um mínimo de atividade de água. Devido sua natureza flexível, é amplamente explorada para catalizar uma diversidade de reações de bioconversão como hidrólise, esterificação, interesterificação, alcoólise, acidólise e aminólise. A propriedade de síntese de esteres a partir de ácidos graxos e glicerol promoveu seu uso em várias sínteses de esteres. Os esteres sintetizados por lipases encontram aplicação em numerosos campos como a produção de biodiesel, resolução de drogas racêmicas, modificação de gorduras e lipídios, sintese de aromas, síntese de produtos farmacêuticos enantiopuro e nutracêuticos. As lipases possuem um papel crucial nas indústrias de

Hepatic lipidosis in llamas and alpacas: 31 cases (1991-1997).

Science.gov (United States)

Tornquist, S J; Van Saun, R J; Smith, B B; Cebra, C K; Snyder, S P

1999-05-01

To identify factors associated with hepatic lipidosis (HL) in llamas and alpacas. Retrospective case series. 30 llamas and 1 alpaca. Medical records were searched to identify llamas or alpacas in which a histologic diagnosis of HL was made. Information was retrieved on signalment, history, clinical and laboratory findings, and results of necropsy or examination of biopsy specimens. Data were analyzed using descriptive statistics and chi 2 analyses. Females were affected more often than males; however, the sex distribution was not different from that of the camelid population in the diagnostic laboratory's database. Fifty-four percent of the females were pregnant, and 46% were lactating. Most affected camelids were 6 to 10 years old. Anorexia and recent weight loss were common (51.6% of camelids). An infective agent was found in only one ilama, and toxins and mineral deficiencies were not identified. The most common abnormalities on serum biochemical analysis were a high concentration of bile acids, high activities of gamma-glutamyltransferase (GGT) and aspartate aminotransferase (AST), and hypoproteinemia. Concentrations of nonesterified fatty acids (NEFA) and beta-hydroxybutyrate (beta-HB) were high in those camelids in which these compounds were assayed. Twenty-nine camelids did not survive. Sick camelids should be considered at risk for developing HL, especially those with anorexia or the metabolic demands of pregnancy and lactation. Other stresses also appear to contribute. High concentrations of NEFA, beta-HB, and bile acids; high activities of GGT and AST; and hypoproteinemia may indicate that HL has developed.

Glycerol Monolaurate Inhibits Lipase Production by Clinical Ocular Isolates Without Affecting Bacterial Cell Viability.

Science.gov (United States)

Flanagan, Judith Louise; Khandekar, Neeta; Zhu, Hua; Watanabe, Keizo; Markoulli, Maria; Flanagan, John Terence; Papas, Eric

2016-02-01

We sought to determine the relative lipase production of a range of ocular bacterial isolates and to assess the efficacy of glycerol monolaurate (GML) in inhibiting this lipase production in high lipase-producing bacteria without affecting bacterial cell growth. Staphylococcus aureus,Staphylococcus epidermidis,Propionibacterium acnes, and Corynebacterium spp. were inoculated at a density of 10(6)/mL in varying concentrations of GML up to 25 μg/mL for 24 hours at 37 °C with constant shaking. Bacterial suspensions were centrifuged, bacterial cell density was determined, and production of bacterial lipase was quantified using a commercial lipase assay kit. Staphylococcus spp. produced high levels of lipase activity compared with P. acnes and Corynebacterium spp. GML inhibited lipase production by Staphylococcal spp. in a dose-dependent manner, with S. epidermidis lipase production consistently more sensitive to GML than S. aureus. Glycerol monolaurate showed significant (P < 0.05) lipase inhibition above concentrations of 15 μg/mL in S. aureus and was not cytotoxic up to 25 μg/mL. For S. epidermidis, GML showed significant (P < 0.05) lipase inhibition above 7.5 μg/mL. Lipase activity varied between species and between strains. Staphylococcal spp. produced higher lipase activity compared with P. acnes and Corynebacterium spp. Glycerol monolaurate inhibited lipase production by S. aureus and S. epidermidis at concentrations that did not adversely affect bacterial cell growth. GML can be used to inhibit ocular bacterial lipase production without proving detrimental to commensal bacteria viability.

Emulsifying triglycerides with dairy phospholipids instead of soy lecithin modulates gut lipase activity

DEFF Research Database (Denmark)

Mathiassen, Jakob Hovalt; Nejrup, Rikke Guldhammer; Frøkiær, Hanne

2015-01-01

in particular to limit fatty acid absorption in babies given infant formulas. Since interaction between the lipid droplet and the gastric and duodenal lipases occur through the hydrophobic/hydrophilic interface, the composition of the emulsifier may be crucial for efficient hydrolysis. We therefore determined...... hydrolytic rate of gastric lipase and pancreatic lipase, on their own or pancreatic lipase after gastric lipase on TAG droplets of similar size emulsified in either soy lecithin (SL) or in bovine milk phospholipids (MPL), more similar to human milk globule membrane lipids than soy lecithin. Gastric lipase...... for formulas for term-born infants....

Study the effect of F17S mutation on the chimeric Bacillus thermocatenulatus lipase

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Seyed Hossein Khaleghinejad

2016-06-01

Full Text Available Lipases (triacylglycerol acylhydrolase, EC 3.1.1.3 are one of the highest value commercial enzymes as they have potential applications in biotechnology for detergents, food, pharmaceuticals, leather, textiles, cosmetics, and paper industries; and are currently receiving considerable attention because of their potential applications in biotechnology. Bacillus thermocatenulatus Lipase 2 (BTL2 is one of the most important research targets, because of its potential industrial applications. In this study, the effect of substitution Phe17 with Ser in mutated BTL2 lipase, which conserved pentapeptide (112Ala-His-Ser-Gln-Gly116 was replaced with similar sequences (207Gly-Glu-Ser-Ala-Gly211 of Candida rugosa lipase (CLR at the nucleophilic elbow region. Docking results confirmed the mutated lipase to be better than the chimeric lipase. So, cloning was conducted, and the mutated and chimeric btl2 genes were expressed in Escherichia coli, and then the enzymes were purified by anion exchange chromatography. The mutation increased lipase lipolytic activity against most of the applied substrates, with the exception of tributyrin when compared with chimeric lipase. Further, the mutated lipase exhibited higher activity than the chimeric lipase at all temperatures. Optimum pH of the mutated lipase was obtained at pH 9.5, which was more than the chimeric one. Enzyme activity of the mutated lipase in the presence of organic solvents, detergents, and metal ions was also improved than the chimeric lipase.

A lipase with broad temperature range from an alkaliphilic gamma-proteobacterium isolated in Greenland

DEFF Research Database (Denmark)

Schmidt, Mariane; Larsen, Dorte Møller; Stougaard, Peter

2010-01-01

A gamma-proteobacterium related to the genera Alteromonadales and Pseudomonadales , isolated from a cold and alkaline environment in Greenland, has been shown to produce a lipase active between 5 ° C and 80 ° C, with optimal activity at 55 ° C and pH 8. PCR-based screening of genomic DNA from...... the isolated bacterium, followed by genome walking, resulted in two complete open reading frames, which were predicted to encode a lipase and its helper protein, a lipase foldase. The amino acid sequence derived for the lipase showed resemblance to lipases from Pseudomonas , Rhodoferax, Aeromonas and Vibrio...... . The two genes were cloned into different expression systems in E. coli with or without a putative secretion sequence, but despite the fact that both recombinant lipase and lipase foldase were observed on SDS–PAGE, no recombinant lipase activity was detected. Attempts to refold the recombinant lipase...

The -250G>A promoter variant in hepatic lipase associates with elevated fasting serum high-density lipoprotein cholesterol modulated by interaction with physical activity in a study of 16,156 Danish subjects

DEFF Research Database (Denmark)

Grarup, Niels; Andreasen, Camilla H; Andersen, Mette K

2008-01-01

-tolerant control subjects (n = 360). RESULTS: In the Inter99 study, the A allele of rs2070895 associated with a 0.057 mmol/liter [95% confidence interval (CI) 0.039-0.075] increase in fasting serum HDL-cholesterol (HDL-c) (P = 8 x 10(-10)) supported by association in the Anglo-Danish-Dutch Study of Intensive...... Treatment in People with Screen Detected Diabetes in Primary Care study [0.038 mmol/liter per allele (95% CI 0.024-0.053); P = 2 x 10(-7)). The allelic effect on HDL-c was modulated by interaction with self-reported physical activity (P(interaction) = 0.002) because vigorous physically active homozygous A...... of variants in LIPC on metabolic traits and type 2 diabetes in a large sample of Danes. Because behavioral factors influence hepatic lipase activity, we furthermore examined possible gene-environment interactions in the population-based Inter99 study. DESIGN: The LIPC -250G>A (rs2070895) variant was genotyped...

Desempenho de diferentes lipases imobilizadas na síntese de biodiesel de óleo de palma = Performance of different immobilized lipases in palm oil biodiesel synthesis

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Grazielle dos Santos Silva

2011-04-01

Full Text Available O presente trabalho teve como objetivo determinar as condicoes otimizadas da sintese enzimatica de biodiesel, a partir do oleo de palma e etanol, empregando diferentes lipases imobilizadas (lipase de Pseudomonas fluorescens imobilizada em SiO2-PVA e lipase de Candida antartica imobilizada em resina acrilica - Novozym„µ 435 em meio isento de solvente. Uma matriz de planejamento fatorial foi utilizada para avaliar a influencia da temperatura (42 ¡V 58„aC e a razao molar entre etanol e oleo de palma (6:1 ¡V 18:1 no rendimento detransesterificacao alcancado para cada preparacao de lipase. Os efeitos principais foram ajustados por analise de regressao multipla a modelos lineares e o rendimento maximo foi obtido quando o sistema operacional foi operado a 42„aC com substratos contendo etanol eoleo de palma na razao molar de 18:1. Os modelos matematicos que representam o rendimento global da reacao para cada lipase imobilizada foram considerados adequados para descrever os resultados experimentais.Optimized conditions for palm oil and ethanol enzymatic biodiesel synthesis were determined with different immobilized lipases SiO2-PVA-immobilized lipase from Pseudomonas fluorescens and acrylic resin-immobilized lipase, NovozymR435, from Candida antartica, in solvent-free medium. A full factorial design assessed the influence oftemperature (42 ¡V 58¢XC and ethanol: palm oil (6:1 ¡V 18:1 molar ratio on the transesterification yield. Main effects were adjusted by multiple regression analysis to linear models and the maximum transesterification yield was obtained at 42¢XC and 18:1 ethanol:palm oil molar ratio. Mathematical models featuring total yield for each immobilized lipase were suitable to describe the experimental results.

AKTIVITAS HIDROLISIS ENZIM LIPASE DARI KENTOS KELAPA TERHADAP MINYAK KELAPA Hidrolysis Activity of Lipase Enzyme from Coconut Houstorium for Coconut Oil

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Mohammad Su’i

2012-05-01

Full Text Available This research was aimed to study hydrolysis conditions of houstorium lipases enzyme using coconut oil as substrate. Hydrolysis conditions studied were substrate (coconut oil concentration, enzyme substrate ratio, duration of hydro- lysis and effect of stirring to hydrolysis. The results show  that lipase of coconut houstorium may be optimally used at a coconut oil concentration of 10 %, enzyme to substrate ratio of 3 : 10 (v/v and hydrolysis for 60 minutes with stirring. ABSTRAK Penelitian ini mempelajari kondisi hidrolisis minyak kelapa yang optimum menggunakan enzim lipase dari kentos kelapa. Kondisi hidrolisis yang dipelajari meliputi konsentrasi substrat optium, perbandingan enzim : substrat dan lama hidrolisis yang optimum serta pengaruh pengadukan selama hidrolisis. Hasil penelitian menunjukkan bahwa, hidrolisis minyak kelapa menggunakan enzim lipase kentos kelapa menghasilkan asam lemak bebas paling banyak pada kon- sentrasi substrat (minyak kelapa 10 %, perbandingan enzim : substrat yaitu 3 : 10 (v/v, lama hidroloisa 60 menit dan dilakukan pengadukan selama hidrolisis.

Streptomyces rimosus GDS(L Lipase: Production, Heterologous Overexpression and Structure-Stability Relationship

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Marija Abramić

2003-01-01

Full Text Available Streptomyces rimosus lipase gene has been overexpressed in a heterologous host, S. lividans TK23. The maximal lipase activity was determined in the culture filtrates of the late stationary phase. Time course of lipase production was monitored by a modified plate assay. S. rimosus lipase gene has been located on the AseI B fragment approximately 2 Mb far from the left end of the S. rimosus linear chromosome. Out of eight examined streptomycetes, the presence of this rare type of bacterial lipase gene was detected in two belonging to the S. rimosus taxonomic cluster, and in one non-related species. Comparison of protein sequences of the Streptomyces lipolytic enzymes was performed. The result indicated the best structural stability of the putative S. coelicolor lipase-2.

The fatty liver dystrophy (fld) mutation: Developmentally related alterations in hepatic triglyceride metabolism and protein expression

Energy Technology Data Exchange (ETDEWEB)

Reue, K.; Rehnmark, S.; Cohen, R.D.; Leete, T.H.; Doolittle, M.H. [West Los Angeles VA Medical Center, CA (United States). Lipid Research Lab.]|[Univ. of California, Los Angeles, CA (United States). Dept. of Medicine; Giometti, C.S.; Mishler, K. [Argonne National Lab., IL (United States); Slavin, B.G. [Univ. of Southern California, Los Angeles, CA (United States)

1997-07-01

Fatty liver dystrophy (fld) is an autosomal recessive mutation in mice characterized by hypertriglyceridemia and development of a fatty liver in the early neonatal period. Also associated with the fld phenotype is a tissue-specific deficiency in the expression of lipoprotein lipase and hepatic lipase, as well as elevations in hepatic apolipoprotein A-IV and apolipoprotein C-II mRNA levels. Although these lipid abnormalities resolve at the age of weaning, adult mutant mice exhibit a peripheral neuropathy associated with abnormal myelin formation. The fatty liver in fld/fld neonates is characterized by the accumulation of large triglyceride droplets within the parenchymal cells, and these droplets persist within isolated hepatocytes maintained in culture for several days. To identify the metabolic defect that leads to lipid accumulation, the authors investigated several aspects of cellular triglyceride metabolism. The mutant mice exhibited normal activity of acid triacylglycerol lipase, an enzyme thought to be responsible for hydrolysis of dietary triglycerides in the liver. Metabolic labeling studies performed with oleic acid revealed that free fatty acids accumulate in the liver of 3 day old fld/fld mice, but not in adults. This accumulation in liver was mirrored by elevated free fatty acid levels in plasma of fld/fld neonates, with levels highest in very young mice and returning to normal by the age of one month. Quantitation of fatty acid oxidation in cells isolated from fld/fld neonates revealed that oxidation rate is reduced 60% in hepatocytes and 40% in fibroblasts; hepatocytes from adult fld/fld mice exhibited an oxidation rate similar to those from wild-type mice.

Spontaneous release of soluble HL-A antigens from platelets during conservation.

Science.gov (United States)

Dautigny, A; Bernier, I; Colombani, J; Jollès, P

1975-01-01

Experiments with the aim of studying the solubilisation of HL-A antigens from blood platelets by methods which do not involve any biologically active processes (moderate, discontinuous agitation of a low concentration of platelets suspended in a saline medium, in the presence of an antiseptic; supernatants collected at frequent intervals) have shown that platelets release membrane proteins, including HL-A antigens, spontaneously. Optimal conditions for the treatment of membrane proteins have been perfected. The great stability of HL-A antigens under these conditions permits prolonged treatment. The products extracted are soluble and extremely complex. The molecular weight of the HL-A antigens is between 40,000 and 70,000.

A Quantitative Fluorescence-Based Lipase Assay

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Giovanna Lomolino

2012-01-01

Full Text Available An easy and fast gel diffusion assay for detecting and monitoring lipase activity by quantification of fluorescein is described. By measuring the intensity of fluorescein, it is possible to obtain a calibration curve with a regression coefficient better than by using the radius of fluorescent haloes. Through the quantification of fluorescence intensity of fluorescein released after the hydrolysis of a fluorescent ester, fluorescein dibutyrate, used as substrate in agar plates, commercial and skimmed milk lipase activity were studied. Moreover, with this method, lipase activity can be monitored in reaction medium that contains compounds which are affected by turbidity or cause measurement interference for UV-spectrophotometer and fluorimeter. In this experiment, boiled skimmed milk was dispersed in the agar gel with fluorescein dibutyrate, and it was used as a reaction medium to mimic natural conditions. The development of such an assay has a potential for applications in industries ranging from pharmaceuticals to food production and monitoring.

Cytotoxicity and cellular uptake of doxorubicin and its formamidine derivatives in HL60 sensitive and HL60/MX2 resistant cells.

Science.gov (United States)

Kik, Krzysztof; Wasowska-Lukawska, Malgorzata; Oszczapowicz, Irena; Szmigiero, Leszek

2009-04-01

In this work a comparison was made of the cytotoxicity and cellular uptake of doxorubicin (DOX) and two of its derivatives containing a formamidino group (-N=CH-N<) at the 3' position with morpholine (DOXM) or hexamethyleneimine (DOXH) ring. All tests were performed in doxorubicin-sensitive HL60 and -resistant HL60/MX2 cells which are known for the presence of altered topoisomerase II. Cytotoxic activity of DOX toward HL60/MX2 cells was about 195 times lower when compared with the sensitive HL60 cell line. DOXM and DOXH were approximately 20 times more active in resistant cells than DOX. It was found that the uptake of DOX was lower in resistant cells by about 16%, while that of DOXM and DOXH was lower by about 36% and 19%, respectively. Thus the changes in the cellular uptake of anthracyclines are not associated with the fact that cytotoxicity of DOXM and DOXH exceed the cytotoxicity of DOX. Experiments in cell-free system containing human topoisomerase II showed that topoisomerase II is not inhibited by DOXM and DOXH. Formamidinoanthracyclines may be more useful than parent drugs in therapy against tumor cells with altered topoisomerase II activity.

Gamma-irradiation sterilization of lipases for cheese making

Energy Technology Data Exchange (ETDEWEB)

Umanskij, M S; Borovkova, Yu A; Odegov, N I [Vsesoyuznyj Nauchno-Issledovatel' skij Inst. Maslodel' noj i Syrodel' noj Promyshlennosti, Uglich (USSR)

1979-03-01

The possibility of sterilizing the enzyme compounds of lipases from Oospora fragrans strains by gamma irradiation was studied. The enzyme compounds were exposed to gamma irradiation at the doses from 0.1 to 0.8 Mrad with the discreteness of 0.1 Mrad and at the dose of 2.0 Mrad. After the radiation treatment the lipases were investigated for bacterial invasion by the cultivation method and for the lipolytic activity by the titrometrical method. It is shown that the sterilization effect is achieved without losses of lipase activity and the radiation dose necessary for sterilization depends on initial invasion levels in the enzyme compounds.

Selection and optimization of extracellular lipase production using ...

African Journals Online (AJOL)

The aim of this study was to isolate and select lipase-producing microorganisms originated from different substrates, as well as to optimize the production of microbial lipase by submerged fermentation under different nutrient conditions. Of the 40 microorganisms isolated, 39 showed a halo around the colonies and 4 were ...

Optimization of lipase production by Staphylococcus sp. Lp12

African Journals Online (AJOL)

USER

2010-02-08

Feb 8, 2010 ... an enormous attention because of their biotechnological applications. Lipases remain ... selective transformations. The exponential increase in .... mass) lipase production and pH at regular intervals of time 24, 48 and 72 h on ...

New lipases by mining of Pleurotus ostreatus genome.

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Alessandra Piscitelli

Full Text Available The analysis of Pleurotus ostreatus genome reveals the presence of automatically annotated 53 lipase and 34 carboxylesterase putative coding-genes. Since no biochemical or physiological data are available so far, a functional approach was applied to identify lipases from P. ostreatus. In the tested growth conditions, four lipases were found expressed, with different patterns depending on the used C source. Two of the four identified proteins (PleoLip241 and PleoLip369, expressed in both analysed conditions, were chosen for further studies, such as an in silico analysis and their molecular characterization. To overcome limits linked to native production, a recombinant expression approach in the yeast Pichia pastoris was applied. Different expression levels were obtained: PleoLip241 reached a maximum activity of 4000 U/L, whereas PleoLip369 reached a maximum activity of 700 U/L. Despite their sequence similarity, these enzymes exhibited different substrate specificity and diverse stability at pH, temperature, and presence of metals, detergents and organic solvents. The obtained data allowed classifying PleoLip241 as belonging to the "true lipase" family. Indeed, by phylogenetic analysis the two proteins fall in different clusters. PleoLip241 was used to remove the hydrophobic layer from wool surface in order to improve its dyeability. The encouraging results obtained with lipase treated wool led to forecast PleoLip241 applicability in this field.

Rhizomucor miehei triglyceride lipase is processed and secreted from transformed Aspergillus oryzae.

Science.gov (United States)

Huge-Jensen, B; Andreasen, F; Christensen, T; Christensen, M; Thim, L; Boel, E

1989-09-01

The cDNA encoding the precursor of the Rhizomucor miehei triglyceride lipase was inserted in an Aspergillus oryzae expression vector. In this vector the expression of the lipase cDNA is under control of the Aspergillus oryzae alpha-amylase gene promoter and the Aspergillus niger glucoamylase gene terminator. The recombinant plasmid was introduced into Aspergillus oryzae, and transformed colonies were selected and screened for lipase expression. Lipase-positive transformants were grown in a small fermentor, and recombinant triglyceride lipase was purified from the culture broth. The purified enzymatically active recombinant lipase (rRML) secreted from A. oryzae was shown to have the same characteristics with respect to mobility on reducing SDS-gels and amino acid composition as the native enzyme. N-terminal amino acid sequencing indicated that approximately 70% of the secreted rRML had the same N-terminal sequence as the native Rhizomucor miehei enzyme, whereas 30% of the secreted rRML was one amino acid residue shorter in the N-terminal. The recombinant lipase precursor, which has a 70 amino acid propeptide, is thus processed in and secreted from Aspergillus oryzae. We have hereby demonstrated the utility of this organism as a host for the production of recombinant triglyceride lipases.

High cell density fed-batch fermentations for lipase production: feeding strategies and oxygen transfer.

Science.gov (United States)

Salehmin, M N I; Annuar, M S M; Chisti, Y

2013-11-01

This review is focused on the production of microbial lipases by high cell density fermentation. Lipases are among the most widely used of the enzyme catalysts. Although lipases are produced by animals and plants, industrial lipases are sourced almost exclusively from microorganisms. Many of the commercial lipases are produced using recombinant species. Microbial lipases are mostly produced by batch and fed-batch fermentation. Lipases are generally secreted by the cell into the extracellular environment. Thus, a crude preparation of lipases can be obtained by removing the microbial cells from the fermentation broth. This crude cell-free broth may be further concentrated and used as is, or lipases may be purified from it to various levels. For many large volume applications, lipases must be produced at extremely low cost. High cell density fermentation is a promising method for low-cost production: it allows a high concentration of the biomass and the enzyme to be attained rapidly and this eases the downstream recovery of the enzyme. High density fermentation enhances enzyme productivity compared with the traditional submerged culture batch fermentation. In production of enzymes, a high cell density is generally achieved through fed-batch operation, not through perfusion culture which is cumbersome. The feeding strategies used in fed-batch fermentations for producing lipases and the implications of these strategies are discussed. Most lipase-producing microbial fermentations require oxygen. Oxygen transfer in such fermentations is discussed.

Vildagliptin and its metabolite M20.7 induce the expression of S100A8 and S100A9 in human hepatoma HepG2 and leukemia HL-60 cells.

Science.gov (United States)

Asakura, Mitsutoshi; Karaki, Fumika; Fujii, Hideaki; Atsuda, Koichiro; Itoh, Tomoo; Fujiwara, Ryoichi

2016-10-19

Vildagliptin is a potent, orally active inhibitor of dipeptidyl peptidase-4 (DPP-4) for the treatment of type 2 diabetes mellitus. It has been reported that vildagliptin can cause hepatic dysfunction in patients. However, the molecular-mechanism of vildagliptin-induced liver dysfunction has not been elucidated. In this study, we employed an expression microarray to determine hepatic genes that were highly regulated by vildagliptin in mice. We found that pro-inflammatory S100 calcium-binding protein (S100) a8 and S100a9 were induced more than 5-fold by vildagliptin in the mouse liver. We further examined the effects of vildagliptin and its major metabolite M20.7 on the mRNA expression levels of S100A8 and S100A9 in human hepatoma HepG2 and leukemia HL-60 cells. In HepG2 cells, vildagliptin, M20.7, and sitagliptin - another DPP-4 inhibitor - induced S100A9 mRNA. In HL-60 cells, in contrast, S100A8 and S100A9 mRNAs were significantly induced by vildagliptin and M20.7, but not by sitagliptin. The release of S100A8/A9 complex in the cell culturing medium was observed in the HL-60 cells treated with vildagliptin and M20.7. Therefore, the parental vildagliptin- and M20.7-induced release of S100A8/A9 complex from immune cells, such as neutrophils, might be a contributing factor of vildagliptin-associated liver dysfunction in humans.

Adipose tissue deficiency of hormone-sensitive lipase causes fatty liver in mice.

Science.gov (United States)

Xia, Bo; Cai, Guo He; Yang, Hao; Wang, Shu Pei; Mitchell, Grant A; Wu, Jiang Wei

2017-12-01

Fatty liver is a major health problem worldwide. People with hereditary deficiency of hormone-sensitive lipase (HSL) are reported to develop fatty liver. In this study, systemic and tissue-specific HSL-deficient mice were used as models to explore the underlying mechanism of this association. We found that systemic HSL deficient mice developed fatty liver in an age-dependent fashion between 3 and 8 months of age. To further explore the mechanism of fatty liver in HSL deficiency, liver-specific HSL knockout mice were created. Surprisingly, liver HSL deficiency did not influence liver fat content, suggesting that fatty liver in HSL deficiency is not liver autonomous. Given the importance of adipose tissue in systemic triglyceride metabolism, we created adipose-specific HSL knockout mice and found that adipose HSL deficiency, to a similar extent as systemic HSL deficiency, causes age-dependent fatty liver in mice. Mechanistic study revealed that deficiency of HSL in adipose tissue caused inflammatory macrophage infiltrates, progressive lipodystrophy, abnormal adipokine secretion and systemic insulin resistance. These changes in adipose tissue were associated with a constellation of changes in liver: low levels of fatty acid oxidation, of very low density lipoprotein secretion and of triglyceride hydrolase activity, each favoring the development of hepatic steatosis. In conclusion, HSL-deficient mice revealed a complex interorgan interaction between adipose tissue and liver: the role of HSL in the liver is minimal but adipose tissue deficiency of HSL can cause age-dependent hepatic steatosis. Adipose tissue is a potential target for treating the hepatic steatosis of HSL deficiency.

Lipase polystyrene giant amphiphiles.

Science.gov (United States)

Velonia, Kelly; Rowan, Alan E; Nolte, Roeland J M

2002-04-24

A new type of giant amphiphilic molecule has been synthesized by covalently connecting a lipase enzyme headgroup to a maleimide-functionalized polystyrene tail (40 repeat units). The resulting biohybrid forms catalytic micellar rods in water.

NLS-RARα promotes proliferation and inhibits differentiation in HL-60 cells.

Science.gov (United States)

Hu, Xiu-Xiu; Zhong, Liang; Zhang, Xi; Gao, Yuan-Mei; Liu, Bei-Zhong

2014-01-01

A unique mRNA produced in leukemic cells from a t(15;17) acute promyelocytic leukemia (APL) patient encodes a fusion protein between the retinoic acid receptor α (RARα) and a myeloid gene product called PML. Studies have reported that neutrophil elastase (NE) cleaves bcr-1-derived PML-RARα in early myeloid cells, leaving only the nuclear localization signal (NLS) of PML attached to RARα. The resultant NLS-RARα fusion protein mainly localizes to, and functions within, the cell nucleus. It is speculated that NLS-RARα may act in different ways from the wild-type RARα, but its biological characteristics have not been reported. This study takes two approaches. Firstly, the NLS-RARα was silenced with pNLS-RARα-shRNA. The mRNA and protein expression of NLS-RARα were detected by RT-PCR and Western blot respectively. Cell proliferation in vitro was assessed by MTT assay. Flow cytometry (FCM) was used to detect the differentiation of cells. Secondly, the NLS-RARα was over-expressed by preparation of recombinant adenovirus HL-60/pAd-NLS-RARα. The assays of mRNA and protein expression of NLS-RARα, and cell proliferation, were as above. By contrast, cell differentiation was stimulated by all trans retinoic acid (ATRA) (2.5µmol/L) at 24h after virus infection of pAd-NLS-RARα, and then detected by CD11b labeling two days later. The transcription and translation of C-MYC was detected in HL-60/pAd-NLS-RARα cells which treated by ATRA. Our results showed that compared to the control groups, the expression of NLS-RARα was significantly reduced in the HL-60/pNLS-RARα-shRNA cells, and increased dramatically in the HL-60/pAd-NLS-RARα cells. The proliferation was remarkably inhibited in the HL-60/pNLS-RARα-shRNA cells in a time-dependent manner, but markedly promoted in the HL-60/pAd-NLS-RARα cells. FCM outcome revealed the differentiation increased in HL-60/pNLS-RARα-shRNA cells, and decreased in the HL-60/pAd-NLS-RARα cells treated with 2.5µmol/L ATRA. The

Evidence for Transfer of Membranes from Mesenchymal Stem Cells to HL-1 Cardiac Cells.

Science.gov (United States)

Boomsma, Robert A; Geenen, David L

2014-01-01

This study examined the interaction of mouse bone marrow mesenchymal stem cells (MSC) with cardiac HL-1 cells during coculture by fluorescent dye labeling and then flow cytometry. MSC were layered onto confluent HL-1 cell cultures in a 1 : 4 ratio. MSC gained gap junction permeant calcein from HL-1 cells after 4 hours which was partially reduced by oleamide. After 20 hours, 99% MSC gained calcein, unaffected by oleamide. Double-labeling HL-1 cells with calcein and the membrane dye DiO resulted in transfer of both calcein and DiO to MSC. When HL-1 cells were labeled with calcein and MSC with DiO, MSC gained calcein while HL-1 cells gained DiO. Very little fusion was observed since more than 90% Sca-1 positive MSC gained DiO from HL-1 cells while less than 9% gained gap junction impermeant CMFDA after 20 hours with no Sca-1 transfer to HL-1 cells. Time dependent transfer of membrane DiD was observed from HL-1 cells to MSC (100%) and vice versa (50%) after 20 hours with more limited transfer of CMFDA. These results demonstrate that MSC and HL-1 cells exchange membrane components which may account for some of the beneficial effect of MSC in the heart after myocardial infarction.

Initial analysis of the HL-2A tokamak visible light measurements

International Nuclear Information System (INIS)

Shi Le; Zheng Yinjia

2005-01-01

Measurement of H α radial distribution is an important part in a plasma experiment. During the HL-2A experiment, CCD photos recorded the plasma radiation information using a plasma imaging system, particularly the H α line emission information (with H α filter in front of the camera). Since the line of light radiation measurement involves a line integral of the radiating region, data handling and analysis are necessary. The H α radial distribution along an HL-2A tokamak radial radius can be obtained by using an Abel inversion transformation with plasma imaging on the HL-2A tokamak. This paper provides a reliable measurement method on the HL-2A tokamak. (authors)

Plant latex lipase as biocatalysts for biodiesel production | Mazou ...

African Journals Online (AJOL)

Plant latex lipase as biocatalysts for biodiesel production. ... This paper provides an overview regarding the main aspects of latex, such as the reactions catalyzed, physiological functions, specificities, sources and their industrial applications. Keywords: Plant latex, lipase, Transesterification, purification, biodiesel ...

Isolation and characterization of lipase-producing Bacillus strains ...

African Journals Online (AJOL)

Bacillus strains (B1 - B5) producing extra cellular lipase were isolated from the soil sample of coconut oil industry. The strains were identified by morphological and biochemical characters. Growth of the organisms and lipase production were measured with varying pH (4 - 9) temperature (27, 37 and 47ºC) and various ...

Production of extracellular lipase by the phytopathogenic fungus Fusarium solani FS1 Produção de lipase extracelular pelo fungo fitopatogênico Fusarium solani FS1

Directory of Open Access Journals (Sweden)

Maria de Mascena Diniz Maia

1999-12-01

Full Text Available A Brazilian strain of Fusarium solani was tested for extracellular lipase production in peptone-olive oil medium. The fungus produced 10,500 U.l-1 of lipase after 72 hours of cultivation at 25oC in shake-flask at 120 rpm in a medium containing 3% (w/v peptone plus 0.5% (v/v olive oil. Glucose (1% w/v was found to inhibit the inductive effect of olive oil. Peptone concentrations below 3% (w/v resulted in a reduced lipase production while increased olive oil concentration (above 0.5% did not further stimulate lipase production. The optimum lipase activity was achieved at pH 8.6 and 30oC and a good enzyme stability (80% activity retention was observed at pH ranging from 7.6 to 8.6, and the activity rapidly dropped at temperatures above 50oC. Lipase activity was stimulated by the addition of n-hexane to the culture medium supernatants, in contrast to incubation with water-soluble solvents.

Serum Beta Hydroxybutyrate Concentrations in Cats with Chronic Kidney Disease, Hyperthyroidism, or Hepatic Lipidosis.

Science.gov (United States)

Gorman, L; Sharkey, L C; Armstrong, P J; Little, K; Rendahl, A

2016-01-01

Ketones, including beta hydroxybutyrate (BHB), are produced in conditions of negative energy balance and decreased glucose utilization. Serum BHB concentrations in cats are poorly characterized in diseases other than diabetes mellitus. Serum BHB concentrations will be increased in cats with chronic kidney disease (CKD), hyperthyroidism (HT), or hepatic lipidosis (HL). Twenty-eight client-owned cats with CKD, 34 cats with HT, and 15 cats with HL; 43 healthy cats. Prospective observational study. Serum BHB concentrations were measured at admission in cats with CKD, HT, and HL, for comparison with a reference interval established using healthy cats. Results of dipstick urine ketone measurement, when available, were compared to BHB measurement. Beta hydroxybutyrate was above the reference interval (<0.11 mmol/L) in 6/28 cats (21%) with CKD, 7/34 cats (20%) with HT, and 11/15 cats (73%) with HL, significantly exceeding the expected 2.5% above the reference interval for healthy cats (P < .001 for all groups). Elevations were mild in CKD and HT groups (median BHB 0.1 mmol/L for both groups, 80th percentile 0.12 and 0.11 mmol/L, respectively), but more marked in HL cats (median BHB 0.2 mmol/L, 80th percentile 0.84 mmol/L). None of 11 cats with increased serum BHB concentration having urine dipstick analysis performed within 24 h of sampling for BHB were ketonuric. Increases in serum BHB concentrations occur in cats with CKD, HT, and HL, and might provide an useful index of catabolism. Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Lipase inhibition and antiobesity effect of Atractylodes lancea.

Science.gov (United States)

Jiao, Ping; Tseng-Crank, Julie; Corneliusen, Brandon; Yimam, Mesfin; Hodges, Mandee; Hong, Mei; Maurseth, Catherine; Oh, Misun; Kim, Hyunjin; Chu, Min; Jia, Qi

2014-05-01

The ethanol extract of Atractylodes lancea rhizome displayed significant lipase inhibition with an IC50 value of 9.06 µg/mL in a human pancreatic lipase assay from high-throughput screening. Bioassay-guided isolation led to the identification of one new polyacetylene, syn-(5E,11E)-3-acetoxy-4-O-(3-methylbutanoyl)-1,5,11-tridecatriene-7,9-diyne-3,4-diol (7), along with six known compounds (1-6). The structure of compound 7 was determined based on the analysis of NMR and MS data. Among these seven lipase inhibitors, the major compound atractylodin (1) showed the highest lipase inhibitory activity (IC50 = 39.12 µM). The antiobesity effect of the ethanol extract of Atractylodes lancea rhizome was evaluated in a high-fat diet-induced obesity mice model at daily dosages of 250 mg/kg and 500 mg/kg body weight for 4 weeks, and treatment with this extract demonstrated a moderate efficacy at the 500 mg/kg dose level. Georg Thieme Verlag KG Stuttgart · New York.

Connecting HL Tau to the observed exoplanet sample

Science.gov (United States)

Simbulan, Christopher; Tamayo, Daniel; Petrovich, Cristobal; Rein, Hanno; Murray, Norman

2017-08-01

The Atacama Large Millimeter/submilimeter Array (ALMA) recently revealed a set of nearly concentric gaps in the protoplanetary disc surrounding the young star HL Tauri (HL Tau). If these are carved by forming gas giants, this provides the first set of orbital initial conditions for planets as they emerge from their birth discs. Using N-body integrations, we have followed the evolution of the system for 5 Gyr to explore the possible outcomes. We find that HL Tau initial conditions scaled down to the size of typically observed exoplanet orbits naturally produce several populations in the observed exoplanet sample. First, for a plausible range of planetary masses, we can match the observed eccentricity distribution of dynamically excited radial velocity giant planets with eccentricities >0.2. Secondly, we roughly obtain the observed rate of hot Jupiters around FGK stars. Finally, we obtain a large efficiency of planetary ejections of ≈2 per HL Tau-like system, but the small fraction of stars observed to host giant planets makes it hard to match the rate of free-floating planets inferred from microlensing observations. In view of upcoming Gaia results, we also provide predictions for the expected mutual inclination distribution, which is significantly broader than the absolute inclination distributions typically considered by previous studies.

Raman spectrum reveals Mesenchymal stem cells inhibiting HL60 cells growth

Science.gov (United States)

Su, Xin; Fang, Shaoyin; Zhang, Daosen; Zhang, Qinnan; Lu, Xiaoxu; Tian, Jindong; Fan, Jinping; Zhong, Liyun

2017-04-01

Though some research results reveals that Mesenchymal stem cells (MSCs) have the ability of inhibiting tumor cells proliferation, it remains controversial about the precise interaction mechanism during MSCs and tumor cells co-culture. In this study, combing Raman spectroscopic data and principle component analysis (PCA), the biochemical changes of MSCs or Human promyelocytic leukemia (HL60) cells during their co-culture were presented. The obtained results showed that some main Raman peaks of HL60 assigned to nucleic acids or proteins were greatly higher in intensity in the late stage of co-culture than those in the early stage of co-culture while they were still lower relative to the control group, implicating that the effect of MSCs inhibiting HL60 proliferation appeared in the early stage but gradually lost the inhibiting ability in the late stage of co-culture. Moreover, some other peaks of HL60 assigned to proteins were decreased in intensity in the early stage of co-culture relative to the control group but rebounded to the level similar to the control group in the late stage, showing that the content and structure changes of these proteins might be generated in the early stage but returned to the original state in the late stage of co-culture. As a result, in the early stage of MSCs-HL60 co-culture, along with the level of Akt phosphorylation of HL60 was lowered relative to its control group, the proliferation rate of HL60 cells was decreased. And in the late stage of co-culture, along with the level of Akt phosphorylation was rebounded, the reverse transfer of Raman peaks within 875-880 cm- 1 appeared, thus MSCs lost the ability to inhibit HL60 growth and HL60 proliferation was increased. In addition, it was observed that the peak at 811 cm- 1, which is a marker of RNA, was higher in intensity in the late stage than that in the control group, indicating that MSCs might be differentiated into myofibroblast-like MSCs. In addition, PCA results also exhibited

Comparative performance of microbial lipases immobilized on magnetic polysiloxane polyvinyl alcohol particles

Directory of Open Access Journals (Sweden)

Laura Maria Bruno

2008-10-01

Full Text Available Microbial lipase from Mucor miehei and Candida rugosa were immobilized by covalent binding onto magnetized polysiloxane polyvinyl alcohol particles (POS-PVA. The resulting immobilized derivatives were evaluated in aqueous solution (olive oil hydrolysis and organic solvent (butyl butyrate synthesis. Higher catalytic activities were found when the coupling procedure was made with M. miehei lipase. Immobilized M. miehei lipase also showed a better operational stability and a higher half-life than C. rugosa lipase after the successive batches of esterification. The performance of C. rugosa immobilized derivative was constrained by the low lipase loading used in the immobilizing step. Further information regarding the both immobilized derivatives was also obtained through chemical composition (FTIR.Lipases microbianas de Mucor miehei e Candida rugosa foram imobilizadas por ligação covalente em partículas magnetizadas de polisiloxano-álcool polivinílico (POS-PVA. Os derivados imobilizados resultantes foram avaliados em solução aquosa (hidrólise de azeite de oliva e em solvente orgânico (síntese de butirato de butila. As maiores atividades catalíticas foram encontradas quando o procedimento de ligação foi realizado com lipase de M. miehei. O derivado imobilizado de lipase de M. miehei também apresentou melhores resultados de estabilidade operacional e tempo de meia-vida do que o de lipase de C. rugosa, após sucessivas bateladas de esterificação. O desempenho do derivado imobilizado de C. rugosa foi restringido pelo baixo carregamento de lipase usado na etapa de imobilização. Informações adicionais a respeito de ambos derivados imobilizados também foram obtidas através da composição química (FTIR.

Lipases de látex vegetais: propriedades e aplicações industriais

Directory of Open Access Journals (Sweden)

Paques Fernanda Wiermann

2006-01-01

Full Text Available Biocatalysts have innumerous advantages with respect to classical chemical processes, such as high specificity. Lipases (EC 3.1.1.3 are biocatalysts with large application in synthesis and hydrolysis reactions of triacylglycerols. The search for new sources of lipases has been intensified in the last years due to the high cost of microbial and animal lipases, wich restricts their use on an industrial scale. Lipases obtained from the latex of Carica papaya, Carica pentagona, Euphorbia characias, E. wulfenii, known for their proteolytic properties, are a good alternative source. In this review, we describe the well-known sources of vegetal lipases extracted from the latex and present some of their industrial applications.

Structural investigations of the regio- and enantioselectivity of lipases

NARCIS (Netherlands)

Lang, Dietmar A.; Dijkstra, Bauke W.

Although lipases are widely applied for the stereospecific resolution of racemic mixtures of esters, the atomic details of the factors that are responsible for their stereospecificity are largely obscure. We determined the X-ray structures of Pseudomonas cepacia lipase in complex with two

Endothelial and lipoprotein lipases in human and mouse placenta

DEFF Research Database (Denmark)

Lindegaard, Marie L S; Olivecrona, Gunilla; Christoffersen, Christina

2005-01-01

Placenta expresses various lipase activities. However, a detailed characterization of the involved genes and proteins is lacking. In this study, we compared the expression of endothelial lipase (EL) and LPL in human term placenta. When placental protein extracts were separated by heparin-Sepharos...

Purification and Characterization of Lipase from Aspergillus flavus ...

African Journals Online (AJOL)

USER

Abstract. Lipase from Aspergillus flavus was purified in a single step purification using MnFeO4 magnetic nano particles to achieve a 20.53- fold purification with specific activity of. 11.29 U/mg and a 59% recovery yield. SDS-PAGE of lipase showed a single pure band with corresponding molecular weight of 35 kDa.

Purification and Characterization of Lipase from Aspergillus flavus ...

African Journals Online (AJOL)

Lipase from Aspergillus flavus was purified in a single step purification using MnFeO4 magnetic nano particles to achieve a 20.53- fold purification with specific activity of 11.29 U/mg and a 59% recovery yield. SDS-PAGE of lipase showed a single pure band with corresponding molecular weight of 35 kDa. The optimal ...

Lipase applications in oil hydrolysis with a case study on castor oil: a review.

Science.gov (United States)

Goswami, Debajyoti; Basu, Jayanta Kumar; De, Sirshendu

2013-03-01

Lipase (triacylglycerol acylhydrolase) is a unique enzyme which can catalyze various types of reactions such as hydrolysis, esterification, alcoholysis etc. In particular, hydrolysis of vegetable oil with lipase as a catalyst is widely studied. Free lipase, lipase immobilized on suitable support, lipase encapsulated in a reverse micelle and lipase immobilized on a suitable membrane to be used in membrane reactor are the most common ways of employing lipase in oil hydrolysis. Castor oil is a unique vegetable oil as it contains high amounts (90%) of a hydroxy monounsaturated fatty acid named ricinoleic acid. This industrially important acid can be obtained by hydrolysis of castor oil. Different conventional hydrolysis processes have certain disadvantages which can be avoided by a lipase-catalyzed process. The degree of hydrolysis varies widely for different lipases depending on the operating range of process variables such as temperature, pH and enzyme loading. Immobilization of lipase on a suitable support can enhance hydrolysis by suppressing thermal inactivation and estolide formation. The presence of metal ions also affects lipase-catalyzed hydrolysis of castor oil. Even a particular ion has different effects on the activity of different lipases. Hydrophobic organic solvents perform better than hydrophilic solvents during the reaction. Sonication considerably increases hydrolysis in case of lipolase. The effects of additives on the same lipase vary with their types. Nonionic surfactants enhance hydrolysis whereas cationic and anionic surfactants decrease it. A single variable optimization method is used to obtain optimum conditions. In order to eliminate its disadvantages, a statistical optimization method is used in recent studies. Statistical optimization shows that interactions between any two of the following pH, enzyme concentration and buffer concentration become significant in presence of a nonionic surfactant named Span 80.

Covalent immobilization of lipase from Candida rugosa on Eupergit®

Directory of Open Access Journals (Sweden)

Bezbradica Dejan I.

2005-01-01

Full Text Available An approach is presented for the stable covalent immobilization of Upase from Candida rugosa on Eupergit® with a high retention of hydrolytic activity. It comprises covalent bonding via lipase carbohydrate moiety previously modified by periodate oxidation, allowing a reduction in the involvement of the enzyme functional groups that are probably important in the catalytic mechanism. The hydrolytic activities of the lipase immobilized on Eupergif1 by two conventional methods (via oxirane group and via glutaralde-hyde and with periodate method were compared. Results of lipase assays suggest that periodate method is superior for lipase immobilization on Eupergit® among methods applied in this study with respect to both, yield of immobilization and hydrolytic activity of the immobilized enzyme.

[Drug resistance reversal of HL-60/ADR cells by simultaneous suppression of XIAP and MRP].

Science.gov (United States)

Wang, Xiao-Fang; Wang, Chun; Qin, You-Wen; Yan, Shi-Ke; Gao, Yan-Rong

2006-12-01

This study was purposed to explore the mechanisms of drug resistance of HL-60/ADR cells and to compare the reversal drug-resistance effects of antisense oligonucleotides (AS ODN) of XIAP (X-linked inhibitor of apoptosis protein) and AS ODNs of MRP (multidrug resistance-associated protein) by use alone or in combination. Reverse transcription-PCR and Western blot were applied to detect the expression of XIAP, BCL-2, MRP and MDR1 in mRNA and protein levels of HL-60 cells and HL-60/ADR cells, respectively. Fully phosphorothioated AS ODN of XIAP and MRP was delivered into HL-60/ADR cells with Lipofectamine 2000 in the form of liposome-ODN complexes alone or in combination. CCK-8 cell viability assay was used to determine the effect of AS ODN of XIAP and MRP used alone or in combination on the chemotherapy sensitivity of HL-60/ADR cells to daunorubicin (DNR). Reverse transcription-PCR and Western blot were applied to examine the changes of XIAP, MRP in mRNA and protein levels respectively. The results showed that MRP and XIAP were both significantly higher in HL-60/ADR cells than those in HL-60 cells. AS ODN of XIAP and MRP down-regulated the expression of XIAP and MRP in HL-60/ADR cells and increased the sensitivity of HL-60/ADR cells to DNR, respectively. AS ODN of XIAP + MRP did not enhance the inhibition expression of XIAP in HL-60/ADR cells but increased the sensitivity of HL-60/ADR cells to DNR significantly as compared with AS ODN of XIAP (P MRP did not increase the concentration of DNR nor enhanced the inhibition expression of MRP in HL-60/ADR cells but increased the sensitivity of HL-60/ADR cells to DNR significantly (P MRP. It is concluded that both XIAP and MRP may be involved in the drug resistance mechanisms of HL-60/ADR cells. Drug-resistance of HL-60/ADR cells can be reversed significantly when antisense oligonucleotides of XIAP and MRP were used in combination.

Iodine-125-labeled lipoprotein lipase as a tool to detect and study spontaneous lipolysis in bovine milk

International Nuclear Information System (INIS)

Sundheim, G.; Bengtsson-Olivecrona, G.

1986-01-01

The distribution of lipoprotein lipase among cream, casein, and milk serum can be evaluated by addition of a trace amount of 125 I-labeled lipoprotein lipase to milk. Radioactive lipase was distributed in parallel to endogenous lipase under several conditions. In some milk samples, binding of lipase to cream increased when the milk was cooled. Correlation was good between bound labeled lipase and degree of cold-induced lipolysis in corresponding milk samples. Binding of lipase to cream or to casein was not saturable by addition of two-to threefold more lipase than is normally present in milk. In milk with a relatively high fraction of lipase bound to cream, a correspondingly lower fraction was associated with casein, whereas the fraction of lipase in milk serum was similar in all milk samples. Cold-induced binding of lipoprotein lipase to cream was not fully reversed when the milk was warmed again. Heparin released lipase from casein and increased the amount of lipase bound to cream after cooling

The CMS Outer Tracker for HL-LHC

CERN Document Server

Dierlamm, Alexander Hermann

2018-01-01

The LHC is planning an upgrade program, which will bring the luminosity to about $5-7\\times10^{34}$~cm$^{-2}$s$^{-1}$ in 2026, with a goal of an integrated luminosity of 3000 fb$^{-1}$ by the end of 2037. This High Luminosity LHC scenario, HL-LHC, will require a preparation program of the LHC detectors known as Phase-2 Upgrade. The current CMS Tracker is already running beyond design specifications and will not be able to cope with the HL-LHC radiation conditions. CMS will need a completely new Tracker in order to fully exploit the highly demanding operating conditions and the delivered luminosity. The new Outer Tracker system is designed to provide robust tracking as well as Level-1 trigger capabilities using closely spaced modules composed of silicon macro-pixel and/or strip sensors. Research and development activities are ongoing to explore options and develop module components and designs for the HL-LHC environment. The design choices for the CMS Outer Tracker Upgrade are discussed along with some highlig...

Effect of fermentation conditions on lipase production by Candida utilis

Directory of Open Access Journals (Sweden)

SANJA Z. GRBAVCIC

2007-08-01

Full Text Available A wild yeast strain isolated from spoiled soybean oil and identified as Candida utilis initially presented rather low lipase activity (approximately 4 IU dm-3 in submerged culture in a universal yeast medium containing 2 % malt extract. Stu­dies were undertaken to improve the lipase production. The best yields of lipase were obtained with a medium supplemented with caprylic and oleic acids as indu­cers, but higher concentrations of the former (> 0.5 % had a negative effect on the lipase production and cell growth. The type of nitrogen source seemed also to be very important. The highest lipolytic activity of 284 IU dm-3 was achieved after 5 days of fermentation in a medium containing oleic acid and hydrolyzed casein as carbon and nitrogen sources, respectively, and supplemented with Tween 80®. It was shown that optimization of the fermentation conditions can lead to a significant improvement in the lipase production (more than 70-fold higher compared to the initial value obtained in the non-optimized medium.

Characteristics of lipase isolated from coconut (Cocos nucifera linn ...

African Journals Online (AJOL)

GREGO

2007-03-19

Mar 19, 2007 ... Lipase from coconut plant grown under complete nutrient conditions showed ... 35°C and had a broad optimum pH of 7.5 – 8.5. Key words: Lipase .... inhibited by the ex- cess of substrate concentration or change of physio-.

Covalent immobilization of lipases on monodisperse magnetic microspheres modified with PAMAM-dendrimer

Energy Technology Data Exchange (ETDEWEB)

Zhu, Weiwei [Lanzhou University, State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Institute of Biochemical Engineering and Environmental Technology (China); Zhang, Yimei [Suzhou Research Academy of North China Electric Power University (China); Hou, Chen; Pan, Duo; He, Jianjun; Zhu, Hao, E-mail: zhuhao07@lzu.edu.cn [Lanzhou University, State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Institute of Biochemical Engineering and Environmental Technology (China)

2016-02-15

This paper reported an immobilization of Candida rugosa lipase (CRL) onto PAMAM-dendrimer-grafted magnetic nanoparticles synthesized by a modified solvothermal reduction method. The dendritic magnetic nanoparticles were amply characterized by several instrumental measurements, and the CRL was covalently anchored on the three generation supports with glutaraldehyde as coupling reagent. The amount of immobilized enzyme was up to 150 mg/g support and the factors related with the enzyme activity were investigated. The immobilization of lipase improved their performance in wider ranges of pH and temperature. The immobilized lipase exhibited excellent thermal stability and reusability in comparison with free enzyme and can be reused 10 cycles with the enzymatic activity remained above 90 %. The properties of lipase improved obviously after being immobilized on the dendritic supports. The inactive immobilized lipase could be regenerated with glutaraldehyde and Cu{sup 2+}, respectively. This synthetic strategy was facile and eco-friendly for applications in lipase immobilization.

An experimental study of 99Tcm-HL91 in detection of myocardial viability

International Nuclear Information System (INIS)

Xu Tao; Liu Baoping; Meng Yubao; Sun Bingqi; Niu Guangjun; Han Xingmin; Yuan Qiao

2005-01-01

Objective: To investigate whether 99 Tc m -4,9-diaza-3,3,10,10-tetramethyldodecan-2,11-dione dioxime (HL91) can be used to distinguish ischemic myocardium segments from infarction segments. Methods: Twenty-five acute myocardial infarction patients (≤6 weeks) and 5 old myocardial infarction patients (> 6 weeks) were included in the study. All the study patients underwent 99 Tc m -HL91 and 99 Tc m -methoxyisobutylisonitrile (MIBI) imaging intervented and unintervented with nitroglycerin, and the myocardium segments were divided into three groups according to 99 Tc m -MIBI imaging results: normal, ischemic, and infarction myocardium segments. The difference of the radial counts of 99 Tc m -HL91 in three groups were analyzed after the imaging with 99 Tc m -HL91. Results: 1) In acute myocardial infarction patients, the accumulation rates of 99 Tc m -HL91 was 95% in normal segment group, 157% in ischemic group, 93% in infarction group. The accumulation rates of 99 Tc m -HL91 in the ischemic group was higher than that in the normal group and infarction group. 2)In old myocardial infarction patients, the accumulation rates of 99 Tc m -HL91 were of no difference among the normal, ischemic, and infarction groups. Conclusion: 99 Tc m -HL91 is a potential marker for detecting the ischemic myocardial tissue. (authors)

Síntese do butirato de n-butila empregando lipase microbiana imobilizada em copolímero de estireno-divinilbenzeno Synthesis of butyl butyrate by microbial lipase immobilized onto styrene-divinylbenzene copolymer

Directory of Open Access Journals (Sweden)

Pedro Carlos de Oliveira

2000-10-01

Full Text Available This work investigates the reaction parameters of an immobilized lipase in the esterification reaction of n-butanol and butyric acid. Microbial lipase from Candida rugosa was immobilized onto styrene-divinylbenzene copolymer (STY-DVB and subsequently introduced in an organic medium containing substrates in appropriate concentrations. Heptane was selected as solvent on the basis of its compatibility with the resin and the enzyme. The influence of molar ratio of acid to alcohol, amount of immobilized lipase and temperature on the butyl butyrate formation was determined. The results were compared with those achieved with free lipase and Lipozyme (commercially immobilized lipase under the same operational conditions.

H/L transition time estimation in JET using conformal predictors

Energy Technology Data Exchange (ETDEWEB)

Gonzalez, S., E-mail: sergio.gonzalez@ciemat.es [Asociacion EURATOM/CIEMAT para Fusion, Madrid 28040 (Spain); Vega, J. [Asociacion EURATOM/CIEMAT para Fusion, Madrid 28040 (Spain); Murari, A. [Consorzio RFX, Associazione EURATOM/ENEA per la Fusione, Padova 4-25127 (Italy); Pereira, A. [Asociacion EURATOM/CIEMAT para Fusion, Madrid 28040 (Spain); Dormido-Canto, S.; Ramirez, J.M. [Departamento de Informatica y Automatica, UNED, Madrid 28040 (Spain)

2012-12-15

Highlights: Black-Right-Pointing-Pointer H/L transitions have been predicted using H/L and L/H models. Black-Right-Pointing-Pointer Models have been built using conformal predictors to hedge the prediction with confidence and credibility measures. Black-Right-Pointing-Pointer Models have been trained using linear and radial basis function kernels. Black-Right-Pointing-Pointer Conformal measures have proven their usefulness to validate data-driven models. - Abstract: Recent advances in data mining allow the automatic recognition of physical phenomena in the databases of fusion devices without human intervention. This is important to create large databases of physical events (thereby increasing the statistical relevance) in an unattended manner. Important examples are the L/H and H/L transitions. In this contribution, a novel technique is introduced to automatically locate H/L transitions in JET by using conformal predictors. The focus is on H/L transitions because typically there is not a clear signature in the time series of the most widely available signals to recognize the change of confinement. Conformal predictors hedge their prediction by means of two parameters: confidence and credibility. The technique has been based on binary supervised classifiers to separate the samples of the respective confinement modes. Results with several underlying classifiers are presented.

Secoiridoids from the stem barks of Fraxinus rhynchophylla with pancreatic lipase inhibitory activity.

Science.gov (United States)

Ahn, Jong Hoon; Shin, Eunjin; Liu, Qing; Kim, Seon Beom; Choi, Kyeong-Mi; Yoo, Hwan-Soo; Hwang, Bang Yeon; Lee, Mi Kyeong

2013-01-01

Pancreatic lipase digests dietary fats by hydrolysis, which is a key enzyme for lipid absorption. Therefore, reduction of fat absorption by the inhibition of pancreatic lipase is suggested to be a therapeutic strategy for obesity. From the EtOAc-soluble fraction of the stem barks of Fraxinus rhynchophylla (Oleaceae), four secoiridoids such as ligstroside (1), oleuropein (2), 2"-hydroxyoleuropein (3) and hydroxyframoside B (4) were isolated. The inhibitory activity of these compounds on pancreatic lipase was assessed using porcine pancreatic lipase as an in vitro assay system. Compound 4 showed the strongest inhibition on pancreatic lipase, which followed by compounds 1-3. In addition, compound 4 exerted inhibitory effect on pancreatic lipase in a mixed mechanism of competitive and noncompetitive manner. Taken together, F. rhynchophylla and its constituents might be beneficial to obesity.

Lipase Test

Science.gov (United States)

... PF4 Antibody Hepatitis A Testing Hepatitis B Testing Hepatitis C Testing HER2/neu Herpes Testing High-sensitivity C-reactive Protein (hs-CRP) Histamine Histone Antibody HIV Antibody and HIV Antigen (p24) HIV Antiretroviral Drug Resistance Testing, Genotypic HIV Viral Load HLA Testing HLA- ...

Improvement of lipase production at different stirring speeds and oxygen levels

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F.O.M. Alonso

2005-03-01

Full Text Available Lipase production by a Brazilian wild strain of Yarrowia lipolytica at different stirring speeds and air flow rates was studied. The relationship among lipid consumption, cell growth and lipase production by this microorganism is presented. The most pronounced effect of oxygen on lipase production was determined by stirring speed. Maximum lipase activity was detected in the late stationary phase at 200 rpm and an air flow rate of 1-2 dm³/min (0.8-1.7 vvm when the lipid source had been fully consumed. Higher stirring speeds resulted in mechanical and/or oxidative stress, while lower stirring speeds seemed to limit oxygen levels. An increase in the availability of oxygen at higher air flow rates led to faster lipid uptake and anticipation of enzyme release into the culture medium. The highest lipase production was obtained at 200 rpm and 1 dm³/min (0.8 vvm.

Statistical optimization for lipase production from solid waste of vegetable oil industry.

Science.gov (United States)

Sahoo, Rajesh Kumar; Kumar, Mohit; Mohanty, Swati; Sawyer, Matthew; Rahman, Pattanathu K S M; Sukla, Lala Behari; Subudhi, Enketeswara

2018-04-21

The production of biofuel using thermostable bacterial lipase from hot spring bacteria out of low-cost agricultural residue olive oil cake is reported in the present paper. Using a lipase enzyme from Bacillus licheniformis, a 66.5% yield of methyl esters was obtained. Optimum parameters were determined, with maximum production of lipase at a pH of 8.2, temperature 50.8°C, moisture content of 55.7%, and biosurfactant content of 1.693 mg. The contour plots and 3D surface responses depict the significant interaction of pH and moisture content with biosurfactant during lipase production. Chromatographic analysis of the lipase transesterification product was methyl esters, from kitchen waste oil under optimized conditions, generated methyl palmitate, methyl stearate, methyl oleate, and methyl linoleate.

Enzymes used in detergents: Lipases | Hasan | African Journal of ...

African Journals Online (AJOL)

This review describes the applications of microbial lipases in detergents. Enzymes can reduce the environmental load of detergent products as the chemicals used in conventional detergents are reduced; they are biodegradable, non-toxic and leave no harmful residues. Besides lipases, other enzymes are widely used in ...

Optimization of lipase production by Staphylococcus sp. Lp12

African Journals Online (AJOL)

USER

2010-02-08

Feb 8, 2010 ... of the genera Pseudomonas, Bacillus, Staphylococcus,. Achromobacter have been cloned and characterized. Bacterial lipases are mostly inducible enzymes and require some form of oil, fatty acid, fatty acid alcohol or fatty acid ester and surfactants for induction (Immanuel et al., 2008). Lipase biosynthesis ...

Physics Prospects at the HL-LHC with ATLAS

CERN Document Server

Duncan, Anna Kathryn; The ATLAS collaboration

2017-01-01

The High-Luminosity LHC aims to provide a total integrated luminosity of 3000 fb-1 from p-p collisions at $\\sqrt{s}$ = 14 TeV over the course of $\\sim$ 10 years, reaching instantaneous luminosities of up to L = 7.5 $\\times$ 1034cm$^{-2}$s$^{-1}$, corresponding to an average ($\\mu$) of 200 inelastic p-p collisions per bunch crossing. The upgraded ATLAS detector must be able to cope well with increased occupancies and data rates. The performance of the upgrade has been estimated in full simulation studies, assuming expected HL-LHC conditions and a detector configuration intended to maximise physics performance and discovery potential at the HL-LHC. The performance is expected to be similar to what we have now. Simulation studies have been carried out to evaluate the prospects of various benchmark physics analyses to be performed using the upgraded ATLAS detector with the full HL-LHC dataset.

Fatty Acid Signaling: The New Function of Intracellular Lipases

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Zuzana Papackova

2015-02-01

Full Text Available Until recently, intracellular triacylglycerols (TAG stored in the form of cytoplasmic lipid droplets have been considered to be only passive “energy conserves”. Nevertheless, degradation of TAG gives rise to a pleiotropic spectrum of bioactive intermediates, which may function as potent co-factors of transcription factors or enzymes and contribute to the regulation of numerous cellular processes. From this point of view, the process of lipolysis not only provides energy-rich equivalents but also acquires a new regulatory function. In this review, we will concentrate on the role that fatty acids liberated from intracellular TAG stores play as signaling molecules. The first part provides an overview of the transcription factors, which are regulated by fatty acids derived from intracellular stores. The second part is devoted to the role of fatty acid signaling in different organs/tissues. The specific contribution of free fatty acids released by particular lipases, hormone-sensitive lipase, adipose triacylglycerol lipase and lysosomal lipase will also be discussed.

Preliminary applied study of assessment ischemic/viable myocardium by 99Tcm-HL91

International Nuclear Information System (INIS)

Liu Gang; Wu Hua

2004-01-01

Objective: To investigate the representation of 99 Tc m -HL91 in the ischemic myocardium, evaluate the diagnosis value of 99 Tc m -HL91 on hypoxic but viable myocardium. Methods: Six patients with cardiac infarction all underwent 99 Tc m -MIBI SPECT and 99 Tc m -HL91 SPECT. Average radioactivity of ischemic area and normal area were respectively obtained by ROI (2 x 2 pixels) on heart minor axis of images, And the radioactivity ratios of target (ischemic area)-to-non target(normal area)were calculated. Results: In image of 99 Tc m -HL91 SPECT, two patients who's radioactivity coloboma of 99 Tc m -MIBI image could be filled with 99 Tc m -HL91, four patients were not caught sight of obvious filling up. Conclusion 99 Tc m -HL91 can be selectively uptaken by ischemic and hypoxic but viable myocardium. it combination of 99 Tc m -MIBI SPECT may be good for accurate diagnosis and differentiation of viable myocardium. (authors)

Tracking in Dense Environments for the HL-LHC ATLAS Detector

CERN Document Server

Cormier, Felix; The ATLAS collaboration

2018-01-01

Tracking in dense environments, such as in the cores of high-energy jets, will be key for new physics searches as well as measurements of the Standard Model at the High Luminosity LHC (HL-LHC). The HL-LHC will operate in challenging conditions with large radiation doses and high pile-up (up to $\\mu=200$). The current tracking detector will be replaced with a new all-silicon Inner Tracker for the Phase II upgrade of the ATLAS detector. In this talk, characterization of the HL-LHC tracker performance for collimated, high-density charged particles arising from high-momentum decays is presented. In such decays the charged-particle separations are of the order of the tracking detector granularity, leading to challenging reconstruction. The ability of the HL-LHC ATLAS tracker to reconstruct the tracks in such dense environments is discussed and compared to ATLAS Run-2 performance for a variety of relevant physics processes.

Characterization of biotechnologically relevant extracellular lipase produced by Aspergillus terreus NCFT 4269.10

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Bijay Kumar Sethi

2016-03-01

Full Text Available Abstract Enzyme production by Aspergillus terreus NCFT 4269.10 was studied under liquid static surface and solid-state fermentation using mustard oil cake as a substrate. The maximum lipase biosynthesis was observed after incubation at 30 °C for 96 h. Among the domestic oils tested, the maximum lipase biosynthesis was achieved using palm oil. The crude lipase was purified 2.56-fold to electrophoretic homogeneity, with a yield of 8.44%, and the protein had a molecular weight of 46.3 kDa as determined by SDS-PAGE. Enzyme characterization confirmed that the purified lipase was most active at pH 6.0, temperature of 50 °C, and substrate concentration of 1.5%. The enzyme was thermostable at 60 °C for 1 h, and the optimum enzyme–substrate reaction time was 30 min. Sodium dodecyl sulfate and commercial detergents did not significantly affect lipase activity during 30-min incubation at 30 °C. Among the metal ions tested, the maximum lipase activity was attained in the presence of Zn2+, followed by Mg2+ and Fe2+. Lipase activity was not significantly affected in the presence of ethylenediaminetetraacetic acid, sodium lauryl sulfate and Triton X-100. Phenylmethylsulfonyl fluoride (1 mM and the reducing, β-mercaptoethanol significantly inhibited lipase activity. The remarkable stability in the presence of detergents, additives, inhibitors and metal ions makes this lipase unique and a potential candidate for significant biotechnological exploitation.

Production of extracellular lipase by a new strain Staphylococcus ...

African Journals Online (AJOL)

Based on morphological, biochemical and 16S rRNA sequence analysis, the potent isolate was identified as Staphylococcus aureus. The lipase production of the isolate was increased by improving the conditions of production medium. Maximum lipase production (8.11 U/ml) was achieved when 2% punnakka oil was ...

Purification and Characterization of a Thermostable Lipase from Geobacillus thermodenitrificans IBRL-nra

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Anuradha Balan

2012-01-01

Full Text Available Thermostable lipase from Geobacillus thermodenitrificans IBRL-nra was purified and characterized. The production of thermostable lipase from Geobacillus thermodenitrificans IBRL-nra was carried out in a shake-flask system at 65°C in cultivation medium containing; glucose 1.0% (w/v; yeast extract 1.25% (w/v; NaCl 0.45% (w/v olive oil 0.1% (v/v with agitation of 200 rpm for 24 hours. The extracted extracellular crude thermostable lipase was purified to homogeneity by using ultrafiltration, Heparin-affinity chromatography, and Sephadex G-100 gel-filtration chromatography by 34 times with a final yield of 9%. The molecular weight of the purified enzyme was estimated to be 30 kDa after SDS-PAGE analysis. The optimal temperature for thermostable lipase was 65°C and it retained its initial activity for 3 hours. Thermostable lipase activity was highest at pH 7.0 and stable for 16 hours at this pH at 65°C. Thermostable lipase showed elevated activity when pretreated with BaCl2, CaCl2, and KCl with 112%, 108%, and 106%, respectively. Lipase hydrolyzed tripalmitin (C16 and olive oil with optimal activity (100% compared to other substrates.

IDENTIFIKASI POTENSI ENZIM LIPASE DAN SELULASE PADA SAMPAH KULIT BUAH HASIL FERMENTASI

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La Ode Sumarlin

2013-12-01

Full Text Available Fermentation is one of bioconversion to produce profitable anaerobic microbes and to produce various enzymes. Lipases and cellulases are widely used enzymes so far. Cellulases play an important role in bioconversion of organic waste cellulosic materials to glucose, single cell proteins, animal feed, and ethanol. Lipases can also degrade fatty ester bond. Therefore, both enzymes are potential to be used in industry as well as in households. Fermentation of fruit peel waste is an attempt to produce cellulase and lipase that can be carried out in a simple way. Cellulase as says was performed using DNS (3.5-dinitrosalicylic acid and acid-base titration for analysis of lipase using cooking oil as the substrate. The results showed that the highest cellulase activity was obtained from watermelon rind mixed with citrus fruit peel of 0.036 U/mL, and mixed of banana peel and citrus fruit, which was 0.035 U/mL. The optimum lipase activity was at 30 oC, pH 7, and reaction time of 60 minutes. The highest lipase activity (1.36 U/mL was obtained from mixture of watermelon and orange rind. Thus, the fruit peel waste is potential to produce cellulase and lipase by fermentation .

Strategies to Characterize Fungal Lipases for Applications in Medicine and Dairy Industry

Science.gov (United States)

Gopinath, Subash C. B.; Anbu, Periasamy; Lakshmipriya, Thangavel; Hilda, Azariah

2013-01-01

Lipases are water-soluble enzymes that act on insoluble substrates and catalyze the hydrolysis of long-chain triglycerides. Lipases play a vital role in the food, detergent, chemical, and pharmaceutical industries. In the past, fungal lipases gained significant attention in the industries due to their substrate specificity and stability under varied chemical and physical conditions. Fungal enzymes are extracellular in nature, and they can be extracted easily, which significantly reduces the cost and makes this source preferable over bacteria. Soil contaminated with spillage from the products of oil and dairy harbors fungal species, which have the potential to secrete lipases to degrade fats and oils. Herein, the strategies involved in the characterization of fungal lipases, capable of degrading fatty substances, are narrated with a focus on further applications. PMID:23865040

MALDI imaging of enzymatic degradation of glycerides by lipase on textile surface

DEFF Research Database (Denmark)

Hall-Andersen, Jonatan; Kaasgaard, Svend G; Janfelt, Christian

2018-01-01

Most modern laundry detergents contain enzymes such as proteases, amylases, and lipases for more efficient removal of stains containing proteins, carbohydrates, and lipids during wash at low temperature. The function of the lipases is to hydrolyse the hydrophobic triglycerides from fats and oils...... stain and simulating washing cycles using well-defined detergents with lipase concentrations ranging between 0 and 0.5ppm. After washing, the textile swatches as well as cryo-sections of the swatches were imaged using MALDI imaging in positive ion mode at pixel sizes of 15-75μm. Similar samples were...... an inhomogeneous presence of diglycerides after lipase treatment both in planar images of the textile surface as well as in cross-sections suggesting a non-uniform enzyme effect or extraction of the lipase reaction products from the textile....

Anaerobic biodegradability of dairy wastewater pretreated with porcine pancreas lipase

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Adriano Aguiar Mendes

2010-12-01

Full Text Available Lipids-rich wastewater was partial hydrolyzed with porcine pancreas lipase and the efficiency of the enzymatic pretreatment was verified by the comparative biodegradability tests (crude and treated wastewater. Alternatively, simultaneous run was carried out in which hydrolysis and digestion was performed in the same reactor. Wastewater from dairy industries and low cost lipase preparation at two concentrations (0.05 and 0.5% w.v-1 were used. All the samples pretreated with enzyme showed a positive effect on organic matter removal (Chemical Oxygen Demand-COD and formation of methane. The best results were obtained when hydrolysis and biodegradation were performed simultaneously, attaining high COD and color removal independent of the lipase concentration. The enzymatic treatment considerably improved the anaerobic operational conditions and the effluent quality (lower content of suspended solids and less turbidity. Thus, the use of enzymes such as lipase seemed to be a very promising alternative for treating the wastewaters having high fat and grease contents, such as those from the dairy industry.O presente trabalho teve como objetivo o pré-tratamento de efluente da indústria de laticínios na hidrólise de lipídeos, empregando lipase de fonte de células animais de baixo custo disponível comercialmente (pâncreas de porco na formação de gás metano por biodegradabilidade anaeróbia empregando diferentes concentrações de lipase (0,05 e 0,5 % w.v-1. A utilização de lipase no pré-tratamento do efluente acelerou a hidrólise de lipídeos e, conseqüentemente, auxiliou o tratamento biológico resultando na redução da matéria orgânica em termos de Demanda Química de Oxigênio (DQO, cor e sólidos em suspensão como lipídeos. Os melhores resultados em termos de remoção de DQO e cor foram obtidos quando a hidrólise e biodigestão foram realizadas simultaneamente, independente da concentração de lipase empregada. Estes resultados

Selections from 2016: Gaps in HL Tau's Protoplanetary Disk

Science.gov (United States)

Kohler, Susanna

2016-12-01

Editors note:In these last two weeks of 2016, well be looking at a few selections that we havent yet discussed on AAS Nova from among the most-downloaded paperspublished in AAS journals this year. The usual posting schedule will resume after the AAS winter meeting.Gas Gaps in the Protoplanetary Disk Around the Young Protostar HL TauPublished March 2016The dust (left) and gas (right) emission from HL Tau show that the gaps in its disk match up. [Yen et al. 2016]Main takeaway:At the end of last year, the Atacama Large Millimeter/Submillimeter Array released some of its first data including a spectacular observation of a dusty protoplanetary disk around the young star HL Tau. In this follow-up study, a team led by Hsi-Wei Yen (Academia Sinica Institute of Astronomy and Astrophysics, Taiwan) analyzed the ALMA data and confirmed the presence of two gaps in the gas of HL Taus disk, at radii of 28 and 69 AU.Why its interesting:The original ALMA image of HL Taus disk suggests the presence of gaps in disk, but scientists werent sure if they were caused by effects like gravitational instabilities or dust clumping, or if the gaps were created by the presence of young planets. Yen and collaborators showed that gaps in the disks gas line up with gaps in its dust, supporting the model in which these gaps have been carved out by newly formed planets.Added intrigue:The evidence for planets in this disk came as a bit of a surprise, since it was originally believed that it takes tens of millions of years to form planets from the dust of protoplanetary disks but HL Tau is only a million years old. These observations therefore suggest that planets start to form much earlier than we thought.CitationHsi-Wei Yen et al 2016 ApJL 820 L25. doi:10.3847/2041-8205/820/2/L25

Lipase Activity in Fermented Oil Seeds of Africa Locust Bean ...

African Journals Online (AJOL)

acer

was determined. The peak lipase activity for fermented Africa locust bean, Castor seed, and African ..... Lipase by Penicillium restrictum in solid state ... sp. Rev. Microbiol. 28(2): 90-95. Martinek, G.H. (1969). Microbiology and amino acid ...

Physics prospects at the HL-LHC with ATLAS

CERN Document Server

Duncan, Anna Kathryn

2017-01-01

The High-Luminosity LHC aims to provide a total integrated luminosity of 3000 fb$^{-1}$ from proton-proton collisions at $\\sqrt{s}$ = 14 TeV over the course of $\\sim$ 10 years, reaching instantaneous luminosities of up to $L = 7.5 \\times 10^{34} cm^{-2} s^{-1}$, corresponding to an average of 200 inelastic p-p collisions per bunch crossing ($\\mu = 200)$. The upgraded ATLAS detector and trigger system must be able to cope well with increased occupancies and data rates. The performance of the upgrade has been estimated in full simulation studies, assuming expected HL-LHC conditions and a detector configuration intended to maximise physics performance and discovery potential at the HL-LHC, and is expected to be similar to current performance. Fast simulation studies have been carried out to evaluate the prospects of various benchmark physics analyses to be performed using the upgraded ATLAS detector with the full HL-LHC dataset.

Enzymatic production of alkyl esters through alcoholysis: A critical evaluation of lipases and alcohols

DEFF Research Database (Denmark)

Li, Deng; Xu, Xuebing; Gudmundur G, Haraldsson

2005-01-01

This paper focuses on a detailed evaluation of commercially available immobilized lipases and simple monohydric alcohols for the production of alkyl esters from sunflower oil by enzymatic alcoholysis. Six lipases were tested with seven alcohols, including straight and branched-chain primary...... in an increased degree of conversion for all lipases except Novozym 435. The secondary alcohol 2-propanol significantly reduced the alcoholysis reaction with all lipases; however, the branch-chain isobutanol was more advantageous than linear 1-butanol for Novozym 435, Lipozyme RM IM, and Lipase PS-C. Many...

Lipase-nanoporous gold biocomposite modified electrode for reliable detection of triglycerides.

Science.gov (United States)

Wu, Chao; Liu, Xueying; Li, Yufei; Du, Xiaoyu; Wang, Xia; Xu, Ping

2014-03-15

For triglycerides biosensor design, protein immobilization is necessary to create the interface between the enzyme and the electrode. In this study, a glassy carbon electrode (GCE) was modified with lipase-nanoporous gold (NPG) biocomposite (denoted as lipase/NPG/GCE). Due to highly conductive, porous, and biocompatible three-dimensional structure, NPG is suitable for enzyme immobilization. In cyclic voltammetry experiments, the lipase/NPG/GCE bioelectrode displayed surface-confined reaction in a phosphate buffer solution. Linear responses were obtained for tributyrin concentrations ranging from 50 to 250 mg dl(-1) and olive oil concentrations ranging from 10 to 200 mg dl(-1). The value of apparent Michaelis-Menten constant for tributyrin was 10.67 mg dl(-1) and the detection limit was 2.68 mg dl(-1). Further, the lipase/NPG/GCE bioelectrode had strong anti-interference ability against urea, glucose, cholesterol, and uric acid as well as a long shelf-life. For the detection of triglycerides in human serum, the values given by the lipase/NPG/GCE bioelectrode were in good agreement with those of an automatic biochemical analyzer. These properties along with a long self-life make the lipase/NPG/GCE bioelectrode an excellent choice for the construction of triglycerides biosensor. © 2013 Elsevier B.V. All rights reserved.

Biodiesel production by transesterification using immobilized lipase.

Science.gov (United States)

Narwal, Sunil Kumar; Gupta, Reena

2013-04-01

Biodiesel can be produced by transesterification of vegetable or waste oil catalysed by lipases. Biodiesel is an alternative energy source to conventional fuel. It combines environmental friendliness with biodegradability, low toxicity and renewability. Biodiesel transesterification reactions can be broadly classified into two categories: chemical and enzymatic. The production of biodiesel using the enzymatic route eliminates the reactions catalysed under acid or alkali conditions by yielding product of very high purity. The modification of lipases can improve their stability, activity and tolerance to alcohol. The cost of lipases and the relatively slower reaction rate remain the major obstacles for enzymatic production of biodiesel. However, this problem can be solved by immobilizing the enzyme on a suitable matrix or support, which increases the chances of re-usability. The main factors affecting biodiesel production are composition of fatty acids, catalyst, solvents, molar ratio of alcohol and oil, temperature, water content, type of alcohol and reactor configuration. Optimization of these parameters is necessary to reduce the cost of biodiesel production.

Integration of IEEE 1451 and HL7 exchanging information for patients' sensor data.

Science.gov (United States)

Kim, Wooshik; Lim, Suyoung; Ahn, Jinsoo; Nah, Jiyoung; Kim, Namhyun

2010-12-01

HL7 (Health Level 7) is a standard developed for exchanging incompatible healthcare information generated from programs or devices among heterogenous medical information systems. At present, HL7 is growing as a global standard. However, the HL7 standard does not support effective methods for treating data from various medical sensors, especially from mobile sensors. As ubiquitous systems are growing, HL7 must communicate with various medical transducers. In the area of sensor fields, IEEE 1451 is a group of standards for controlling transducers and for communicating data from/to various transducers. In this paper, we present the possibility of interoperability between the two standards, i.e., HL7 and IEEE 1451. After we present a method to integrate them and show the preliminary results of this approach.

Recombinant Lipases and Phospholipases and Their Use as Biocatalysts for Industrial Applications

OpenAIRE

Borrelli, Grazia M.; Trono, Daniela

2015-01-01

Lipases and phospholipases are interfacial enzymes that hydrolyze hydrophobic ester linkages of triacylglycerols and phospholipids, respectively. In addition to their role as esterases, these enzymes catalyze a plethora of other reactions; indeed, lipases also catalyze esterification, transesterification and interesterification reactions, and phospholipases also show acyltransferase, transacylase and transphosphatidylation activities. Thus, lipases and phospholipases represent versatile bioc...

Enzymatic interesterification of palm stearin and coconut oil by a dual lipase system

DEFF Research Database (Denmark)

Ibrahim, Nuzul Amri Bin; Guo, Zheng; Xu, Xuebing

2008-01-01

greater than 100% over the theoretical value when the reaction proceeds for 2 h. The co-immobilization action of the carrier of the immobilized lipases towards the free lipase was proposed as being one of the reasons leading to the synergistic effect and this has been experimentally verified by a reaction......Enzymatic interesterification of palm stearin with coconut oil was conducted by applying a dual lipase system in comparison with individual lipase-catalyzed reactions. The results indicated that a synergistic effect occurred for many lipase combinations, but largely depending on the lipase species...... mixed and their ratios. The combination of Lipozyme TL IM and RM IM was found to generate a positive synergistic action at all test mixing ratios. Only equivalent amount mixtures of Lipozyme TL IM with Novozym 435 or Lipozyme RM IM with Novozym 435 produced a significant synergistic effect as well...

Overview of HL-2A experiment results

International Nuclear Information System (INIS)

Yang, Q.W.; Yong Liu; Ding, X.T.

2007-01-01

Recent experiment results from the HL-2A tokamak are presented in this paper. Supersonic molecular beam injection (SMBI) with liquid nitrogen temperature propellant is used. Low temperature SMBI can form hydrogen clusters that penetrate into the plasma more deeply and efficiently. Particle diffusion coefficient and convection velocity (D = 0.5-1.5 m 2 s -1 and V conv -1 , respectively) are obtained at the plasma periphery using modulated SMBI. Multi-probe measurements reveal the m = 0-1, n = 0 symmetries of directly measured low frequency (7-9 kHz) electric potential and field are simultaneously observed for the first time. Impurity transport is determined with the laser blow-off system and transport code. A disruption predictor has been derived based on MHD activity observations and statistical analysis. Sawtooth characteristics during ECRH are investigated and coupling between m = 1 and m/n = 2/1 modes is studied. Detachment features of HL-2A divertor are numerically and experimentally studied using the code SOLPS5.0 and measured data. The long divertor legs and thin divertor throats in HL-2A pose MHD shaping problems resulting in momentum losses even at low densities and strongly enhanced main chamber losses

Lipase biocatalysis for useful biodegradable products

Energy Technology Data Exchange (ETDEWEB)

Linko, Y Y; Wang, Zhuo Lin; Uosukainen, E; Seppaelae, J [Helsinki Univ. of Technology, Espoo (Finland); Laemsae, M [Raisio Group Oil Milling Industry, Raisio (Finland)

1997-12-31

It was shown that lipases can be used as biocatalysts in the production of useful biodegradable compounds such as 1-butyl oleate by direct esterification of butanol and oleic acid to decrease viscosity of biodiesel in winter use. By enzymic transesterification, a mixture of 2-ethyl-1-hexyl esters from rapeseed oil fatty acids can be obtained in good yields for use as a solvent, and of trimethylolpropane esters for use as a lubricant. Finally, it was demonstrated that polyesters with a mass average molar mass in excess of 75,000 g mol{sup -}1 can be obtained by esterification or transesterification by using lipase as biocatalyst. (author) (3 refs.)

Lipase biocatalysis for useful biodegradable products

Energy Technology Data Exchange (ETDEWEB)

Linko, Y.Y.; Wang, Zhuo Lin; Uosukainen, E.; Seppaelae, J. [Helsinki Univ. of Technology, Espoo (Finland); Laemsae, M. [Raisio Group Oil Milling Industry, Raisio (Finland)

1996-12-31

It was shown that lipases can be used as biocatalysts in the production of useful biodegradable compounds such as 1-butyl oleate by direct esterification of butanol and oleic acid to decrease viscosity of biodiesel in winter use. By enzymic transesterification, a mixture of 2-ethyl-1-hexyl esters from rapeseed oil fatty acids can be obtained in good yields for use as a solvent, and of trimethylolpropane esters for use as a lubricant. Finally, it was demonstrated that polyesters with a mass average molar mass in excess of 75,000 g mol{sup -}1 can be obtained by esterification or transesterification by using lipase as biocatalyst. (author) (3 refs.)

Structural basis of the chiral selectivity of Pseudomonas cepacia lipase

NARCIS (Netherlands)

Lang, Dietmar A.; Mannesse, Maurice L.M.; Haas, Gerard H. de; Verheij, Hubertus M.; Dijkstra, Bauke W.

1998-01-01

To investigate the enantioselectivity of Pseudomonas cepacia lipase, inhibition studies were performed with S(c)-and R(c)-(R(p),S(p))-1,2-dialkylcarbamoylglycero-3-O-p-nitrophenyl alkylphosphonates of different alkyl chain lengths. P. cepacia lipase was most rapidly inactivated by

Metabolic fate of rat heart endothelial lipoprotein lipase

International Nuclear Information System (INIS)

Chajek-Shaul, T.; Bengtsson-Olivecrona, G.; Peterson, J.; Olivecrona, T.

1988-01-01

When isolated rat hearts were perfused with medium containing 125I-labeled bovine lipoprotein lipase (LPL), they bound both lipase activity and radioactivity. More than 80% of the bound lipase could be rapidly released by heparin. Low concentrations of bovine LPL displaced 50-60% of the endogeneous, endothelial-bound LPL. Higher concentrations caused additional binding. Both binding and exchange were rapid processes. The hearts continuously released endogenous LPL into the medium. An antiserum that inhibited bovine but not rat LPL was used to differentiate endogeneous and exogeneous LPL activity. When the pool of endothelial LPL was labeled with bovine 125I-labeled LPL and then chased with unlabeled bovine LPL, approximately 50% of the labeled lipase was rapidly displaced. During chase perfusion with medium only, catalytically active bovine LPL appeared in the perfusate. The rate of release was similar to that observed for endogeneous LPL activity and amounted to 10-13% of the heparin-releasable fraction in the first 5 min of perfusion. There was little or no degradation of bovine 125I-labeled LPL to fragments or acid-soluble products. These results indicate that endothelial LPL is accessible for exchange with exogeneous LPL and that detachment rather than degradation may be the pathway for catabolism of endothelial LPL

Comparison of immunoreactive serum trypsinogen and lipase in Cystic Fibrosis

International Nuclear Information System (INIS)

Lloyd-Still, J.D.; Weiss, S.; Wessel, H.; Fong, L.; Conway, J.J.

1984-01-01

The incidence of Cystic Fibrosis (CF) is 1 in 2,000. Early detection and treatment of CF may necessitate newborn screening with a reliable and cost-effective test. Serum immunoreactive trypsinogen (IRT) an enzyme produced by the pancreas, is detectable by radioimmunoassay (RIA) techniques. Recently, it has been shown that IRT is elevated in CF infants for the first few months of life and levels become subnormal as pancreatic insufficiency progresses. Other enzymes produced by the pancreas, such as lipase, are also elevated during this time. The author's earlier work confirmed previous reports of elevated IRT levels in CF infants. The development of a new RIA for lipase (nuclipase) has enabled comparison of these 2 pancreatic enzymes in C.F. Serum IRT and lipase determinations were performed on 2 groups of CF patients; infants under 1 year of age, and children between 1 and 18 years of age. Control populations of the same age groups were included. The results showed that both trypsin (161 +- 92 ng/ml, range 20 to 400) and lipase (167 +- 151 ng/ml, range 29 to 500) are elevated in CF in the majority of infants. Control infants had values of IRT ranging from 20 to 29.5 ng/ml and lipase values ranging from 23 to 34 ng/ml. IRT becomes subnormal in most CF patients by 8 years of age as pancreatic function insufficiency increases. Lipase levels and IRT levels correlate well in infancy, but IRT is a more sensitive indicator of pancreatic insufficiency in older patients with CF

The preparation and biological characterization of a new HL91-derivative for hypoxic imaging on stroke mice

Energy Technology Data Exchange (ETDEWEB)

Hsia, C.-C. [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taiwan (China); Institute of Nuclear Energy Research, Taiwan (China); Huang, F.-L.; Lin, C.-H.; Shen, L.-H. [Institute of Nuclear Energy Research, Taiwan (China); Wang, H.-E., E-mail: hewang@ym.edu.t [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taiwan (China)

2010-09-15

Aim: {sup 99m}Tc-HL91 (Prognox, GE-Healthcare) was the first nonnitro-aryl-based radiotracer for evaluating hypoxic fraction in neoplasm, stroke and myocardium infarction regions. However, the high hydrophilicity of {sup 99m}Tc-HL91 might hamper its penetration into cells. In this study, we prepared a new ligand 4,4,11,11-tetramethyl- 5,10-diazatetradecane- 3,12-dionedioxime (HL91-ET) with higher lipophilicity but structurally similar compared with that of HL91. The chemical and biological characterizations of {sup 99m}Tc-HL91-ET as a scintigraphic probe for hypoxia were performed with a stroke-bearing mouse model. Materials and Methods: HL91-ET was synthesized and formulated with stannous chloride and buffer to afford kits. After mixing with {sup 99m}Tc-pertechnetate, {sup 99m}Tc-HL91-ET can be prepared in high yield and high radiochemical purity (both >96%). The partition coefficient of {sup 99m}Tc-HL91-ET was determined in n-octanol/PBS system. Cellular uptake assays under normoxic and hypoxic conditions were performed in an oxygen-controlled CO{sub 2} incubator. Brain stroke in the mouse model was induced by the electrocautery of the middle cerebral artery. After intravenous injection of {sup 99m}Tc-HL91-ET into the Balb/c mouse suffering brain stroke, small-animal SPECT images were acquired at designated time points and autoradiography of the brain slides was conducted. Parallel studies of {sup 99m}Tc-HL91 were also conducted at the same conditions for comparison. Results: The higher partition coefficient of {sup 99m}Tc-HL91-ET (0.294{+-}0.007) indicated higher lipophlicity compared with that of {sup 99m}Tc-HL91 (0.089{+-}0.005). The {sup 99m}Tc-HL91-ET preparation was stable at ambient temperature for 24 h. Cellular uptake assay showed that {sup 99m}Tc-HL91-ET was less selectively retained in hypoxic cells than {sup 99m}Tc-HL91. The target-to-normal brain ratios derived from the autoradiograms of the brains of stroke mice were 1.31{+-}0.02 and 17

The preparation and biological characterization of a new HL91-derivative for hypoxic imaging on stroke mice

International Nuclear Information System (INIS)

Hsia, C.-C.; Huang, F.-L.; Lin, C.-H.; Shen, L.-H.; Wang, H.-E.

2010-01-01

Aim: 99m Tc-HL91 (Prognox, GE-Healthcare) was the first nonnitro-aryl-based radiotracer for evaluating hypoxic fraction in neoplasm, stroke and myocardium infarction regions. However, the high hydrophilicity of 99m Tc-HL91 might hamper its penetration into cells. In this study, we prepared a new ligand 4,4,11,11-tetramethyl- 5,10-diazatetradecane- 3,12-dionedioxime (HL91-ET) with higher lipophilicity but structurally similar compared with that of HL91. The chemical and biological characterizations of 99m Tc-HL91-ET as a scintigraphic probe for hypoxia were performed with a stroke-bearing mouse model. Materials and Methods: HL91-ET was synthesized and formulated with stannous chloride and buffer to afford kits. After mixing with 99m Tc-pertechnetate, 99m Tc-HL91-ET can be prepared in high yield and high radiochemical purity (both >96%). The partition coefficient of 99m Tc-HL91-ET was determined in n-octanol/PBS system. Cellular uptake assays under normoxic and hypoxic conditions were performed in an oxygen-controlled CO 2 incubator. Brain stroke in the mouse model was induced by the electrocautery of the middle cerebral artery. After intravenous injection of 99m Tc-HL91-ET into the Balb/c mouse suffering brain stroke, small-animal SPECT images were acquired at designated time points and autoradiography of the brain slides was conducted. Parallel studies of 99m Tc-HL91 were also conducted at the same conditions for comparison. Results: The higher partition coefficient of 99m Tc-HL91-ET (0.294±0.007) indicated higher lipophlicity compared with that of 99m Tc-HL91 (0.089±0.005). The 99m Tc-HL91-ET preparation was stable at ambient temperature for 24 h. Cellular uptake assay showed that 99m Tc-HL91-ET was less selectively retained in hypoxic cells than 99m Tc-HL91. The target-to-normal brain ratios derived from the autoradiograms of the brains of stroke mice were 1.31±0.02 and 17.47±0.10 (n=3), respectively, at 2 h post injection of 99m Tc-HL91-ET and 99m Tc-HL91

Structure and Function of Lipase

DEFF Research Database (Denmark)

Skjold-Jørgensen, Jakob

.e. the waterlipidinterface. For Thermomyces lanuginosus lipase (TlL) and related lipases, activation of the enzymeinvolves a rearrangement of a structural domain, called the “lid”, which covers the active site inhomogenous aqueous solution. At the water-lipid interface, the lid is displaced from the active site andmoves...... the water-lipid interface, structural movements occurring during activation have been difficult to probeexperimentally. In this work, novel variants of TlL were constructed based on rational design with amutated lid-region in order to elucidate the impact of the lid-residue composition and characteristics...... onthe activation mechanism. From characterization studies of these variants we have shown (Paper I) thatthe lid-region plays a crucial role in governing interfacial activation and enzymatic activity. Specifically,using a combination of spectroscopic and enzymatic activity-based methods we have...

The genotypic diversity and lipase production of some thermophilic bacilli from different genera

Directory of Open Access Journals (Sweden)

Melih Koc

2015-12-01

Full Text Available Abstract Thermophilic 32 isolates and 20 reference bacilli were subjected to Rep-PCR and ITS-PCR fingerprinting for determination of their genotypic diversity, before screening lipase activities. By these methods, all the isolates and references could easily be differentiated up to subspecies level from each other. In screening assay, 11 isolates and 7 references were found to be lipase producing. Their extracellular lipase activities were measured quantitatively by incubating in both tributyrin and olive oil broths at 60 °C and pH 7.0. During the 24, 48 and 72-h period of incubation, the changes in the lipase activities, culture absorbance, wet weight of biomass and pH were all measured. The activity was determined by using pNPB in 50 mM phosphate buffer at pH 7.0 at 60 °C. The lipase production of the isolates in olive oil broths varied between 0.008 and 0.052, whereas these values were found to be 0.002-0.019 (U/mL in the case of tyributyrin. For comparison, an index was established by dividing the lipase activities to cell biomass (U/mg. The maximum thermostable lipase production was achieved by the isolates F84a, F84b, and G. thermodenitrificans DSM 465T (0.009, 0.008 and 0.008 U/mg within olive oil broth, whereas G. stearothermophilus A113 displayed the highest lipase activity than its type strain in tyributyrin. Therefore, as some of these isolates displayed higher activities in comparison to references, new lipase producing bacilli were determined by presenting their genotypic diversity with DNA fingerprinting techniques.

Les lipases sont des hydrolases atypiques : principales caractéristiques et applications

Directory of Open Access Journals (Sweden)

Fickers P.

2008-01-01

Full Text Available ipases are atypical hydrolases: principal characteristics and applications. Due to their kinetic and substrate specificities, triacylglycerol acyl-hydrolases or lipases are atypical enzymes. In function of their microenvironment, lipases are able to act as hydrolases in aqueous solution or as biocatalysts in organic synthesis. As hydrolases, they are responsible of the triglycerids catabolism into fatty acids and glycerol. In many organisms, this reaction plays a major role in the fat and lipid metabolism. In addition, lipases are also able to hydrolyse phospholipids and cholesterol esters. In organic solvent, lipases could catalyse reactions such as esterifications, acidolysis or alcoolysis with enantio-, regio- and chimioselectivity. Lipases form a mixed class of enzyme due to their animal, vegetal or microbial origins. All those properties led to the development of many applications in the food and chemical industries but also in the medical and therapeutic field.

Mycelium-Bound Lipase from a Locally Isolated Strain of Geotrichum candidum

Directory of Open Access Journals (Sweden)

Joo Ling Loo

2014-06-01

Full Text Available Mycelium-bound lipase (MBL, from a locally isolated Geotrichum candidum strain, was produced and characterized as a natural immobilized lipase. A time course study of its lipolytic activity in 1 L liquid broth revealed the maximum MBL activity at 4 h for mycelium cells harvested after 54 h. The yield and specific activity of MBL were 3.87 g/L dry weight and 508.33 U/g protein, respectively, while less than 0.2 U/mL lipase activity was detected in the culture supernatant. Prolonged incubation caused release of the bound lipase into the growth medium. The growth pattern of G. candidum, and production and properties of MBL were not affected by the scale. The stability of mycelia harboring lipase (MBL, harvested and lyophilized after 54 h, studied at 4 °C depicted a loss of 4.3% and 30% in MBL activity after 1 and 8 months, while the activity of free lipase was totally lost after 14 days of storage. The MBL from G. candidum displayed high substrate selectivity for unsaturated fatty acids containing a cis-9 double bond, even in crude form. This unique specificity of MBL could be a direct, simple and inexpensive way in the fats and oil industry for the selective hydrolysis or transesterification of cis-9 fatty acid residues in natural triacylglycerols.

Immobilization of lipases in PSS/PEO blends and applications in esters synthesis

International Nuclear Information System (INIS)

Vecchia, Roberto D.; Nascimento, Maria G.; Soldi, Valdir

2001-01-01

Various lipases were immobilized in PSS/PEO blends and used as bio catalysts in the esterification reaction of lauric acid with n-pentanol, in hexane as a solvent for 24 h at 35 deg C. The best results in the ester conversion, were obtained by using lipase from Rhryzopus oryzae immobilized in PSS/PEO 80:20 blend. The data are in agreement with DSC and TGA values, which showed that these systems (blend/lipase) were very stable with low mass loss. No product was obtained by using lipase FAP-15 immobilized in PSS film , showing the strong influence of the polymer on enzyme activity. (author)

Bioconjugation of lipase and cholesterol oxidase with graphene or graphene oxide

Energy Technology Data Exchange (ETDEWEB)

Silva, Rubens A.; Souza, Michele L.; Bloisi, Georgia D.; Corio, Paolo; Petri, Denise F. S., E-mail: dfsp@iq.usp.br [Universidade de São Paulo, Instituto de Química (Brazil)

2015-04-15

The catalytic behavior of lipase and cholesterol oxidase (ChOx) in the absence and in the presence of graphene (G) or graphene oxide (GO) was investigated at 24 ± 1 °C and pH 6.5. GO flat sheets (0.5–2 μm) were ∼2-nm thick, while G formed aggregates. The maximum reaction velocity (V{sub max}) values and turnover numbers (k{sub cat}) determined for reactions catalyzed by physical mixtures of lipase (at 0.01 g l{sup −1}) or ChOx (at 0.03 g l{sup −1}) and G (0.012 g l{sup −1}) increased six-fold or doubled, respectively, in comparison to neat enzymes. Circular dichroism (CD) and photoluminescence (PL) spectroscopic measurements revealed the preservation of native secondary structures of enzymes and bioconjugation driven by hydrophobic interaction and energy transfer (redshift) between lipase or ChOx and G, corroborating with the enhanced catalytic behavior. On the other hand, the interactions between GO, which has hydrophilic moieties on the basal plane, and ChOx caused enzyme deactivation, as evidenced by the absence of typical CD signal. At low GO concentration (<0.012 g l{sup −1}), bioconjugates of lipases with GO led to V{sub max} and k{sub cat} values four-fold lower than their counterparts with G, but the GO hydrophilic groups probably favored the affinity for the substrate, because the Michaelis constant (K{sub m}) values decreased in comparison to that of neat lipase. Upon increasing the GO concentration, lipases lost secondary structure and the typical lipase PL bands disappeared.

Bioconjugation of lipase and cholesterol oxidase with graphene or graphene oxide

International Nuclear Information System (INIS)

Silva, Rubens A.; Souza, Michele L.; Bloisi, Georgia D.; Corio, Paolo; Petri, Denise F. S.

2015-01-01

The catalytic behavior of lipase and cholesterol oxidase (ChOx) in the absence and in the presence of graphene (G) or graphene oxide (GO) was investigated at 24 ± 1 °C and pH 6.5. GO flat sheets (0.5–2 μm) were ∼2-nm thick, while G formed aggregates. The maximum reaction velocity (V max ) values and turnover numbers (k cat ) determined for reactions catalyzed by physical mixtures of lipase (at 0.01 g l −1 ) or ChOx (at 0.03 g l −1 ) and G (0.012 g l −1 ) increased six-fold or doubled, respectively, in comparison to neat enzymes. Circular dichroism (CD) and photoluminescence (PL) spectroscopic measurements revealed the preservation of native secondary structures of enzymes and bioconjugation driven by hydrophobic interaction and energy transfer (redshift) between lipase or ChOx and G, corroborating with the enhanced catalytic behavior. On the other hand, the interactions between GO, which has hydrophilic moieties on the basal plane, and ChOx caused enzyme deactivation, as evidenced by the absence of typical CD signal. At low GO concentration (<0.012 g l −1 ), bioconjugates of lipases with GO led to V max and k cat values four-fold lower than their counterparts with G, but the GO hydrophilic groups probably favored the affinity for the substrate, because the Michaelis constant (K m ) values decreased in comparison to that of neat lipase. Upon increasing the GO concentration, lipases lost secondary structure and the typical lipase PL bands disappeared

Characterization of an extracellular lipase by Pseudomonas koreensis BK-L07 isolated from soil.

Science.gov (United States)

Anbu, Periasamy

2014-01-01

Screening using spirit blue agar revealed that strain BK-L07 had the highest lipase activity. Furthermore, the isolated strain was identified as Pseudomonas sp. based on morphological, physiological, biochemical, and molecular analyses. The 16S rRNA gene sequence of strain BK-L07 shared a high similarity with that of Pseudomonas koreensis (99%). The nutritional conditions and physicochemical properties were influenced by P. koreensis BK-L07. The maximum lipase production was obtained in tryptic soy broth medium at pH 8.0 and a temperature of 25°C after 36 hr of incubation. In addition, the lipase activity was determined using different carbon sources and lipase inducers. The lipase production was greatest when 1% maltose was used as the carbon source and olive oil was used as the lipase inducer. The lipase production was significantly increased approximately threefold in the optimized medium when compared with the original medium. Further, the lipase was purified by ammonium sulfate precipitation and gel filtration chromatography with a purification yield of 10.8%. The molecular mass of lipase was 45 kDa. The optimum temperature and pH were 40°C and 8.0, respectively. The enzyme was stable up to 50°C and at pH from 7 to 9. In addition, the enzyme activity was stimulated by MgSO4 and completely inhibited by ethylenediamine tetraacetic acid (EDTA), indicating the metalloenzyme type. The lipase activity was toward medium to long chain length of fatty acids (C10 to C18). Supplemental materials are available for this article. Go to the publisher's online edition of Preparative Biochemistry and Biotechnology to view the supplemental file.

Pancreatic beta-cell lipotoxicity induced by overexpression of hormone-sensitive lipase

DEFF Research Database (Denmark)

Winzell, Maria Sörhede; Svensson, Håkan; Enerbäck, Sven

2003-01-01

Lipid perturbations associated with triglyceride overstorage in beta-cells impair insulin secretion, a process termed lipotoxicity. To assess the role of hormone-sensitive lipase, which is expressed and enzymatically active in beta-cells, in the development of lipotoxicity, we generated transgenic...... mice overexpressing hormone-sensitive lipase specifically in beta-cells. Transgenic mice developed glucose intolerance and severely blunted glucose-stimulated insulin secretion when challenged with a high-fat diet. As expected, both lipase activity and forskolin-stimulated lipolysis was increased...

Preliminary clinical study of 99Tcm-HL91 imaging in bone metastasis

International Nuclear Information System (INIS)

Liu Baoping; Mao Ronghu; Han Xingmin

2008-01-01

Objective: 99 Tc m -4, 9-diaza-3, 3, 10, 10-tetramethyldodecan-2, 11-dione dioxime (HL91), a new type of hypoxic agents, accumulates in tumor hypoxic tissue specifically. The aim of this study was to evaluate the value of 99 Tc m -HL91 imaging in the diagnosis of bone metastasis. Methods: Nine- teen cases with bone metastasis (without any treatment) and 8 cases with benign lesions underwent SPECT imaging at 4 h after injection of 740 MBq of 99 Tc m -HL91 along with 99 Tc m -methylene diphosphonic acid (MDP) imaging. Regions of interest (ROIs) were drawn in tumor tissue and contralateral normal tissue respectively, and the radioactivity ratios of tumor-to-normal (T/N) were calculated. The t-test was used for data analysis with SPSS 11.0. Results: There were visible uptake of 99 Tc m -HL91 in 79 out of 85 focuses in 19 patients of bone metastasis; however, there was no obvious uptake of 99 Tc m -HL91 in 12 focuses of 8 patients of benign lesions. Significant difference existed between the T/N values of malignant (1.877 ± 0.288) and benign lesions [(0.735 ± 0.236); t=13.065, P 0.05). Conclusion: The results indicated that 99 Tc m -HL91 was useful in diagnosing the malignant and benign bone lesions. (authors)

Overexpression of Fusarium solani lipase in Pichia pastoris and its application in lipid degradation

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Jinaporn Wongwatanapaiboon

2016-09-01

Full Text Available Fusarium solani NAN103 lipase was successfully overexpressed in Pichia pastoris using inducible expression system and constitutive expression system under the control of alcohol oxidase 1 promoter (pAOX1 and glyceraldehyde-3-phosphate dehydrogenase promoter (pGAP, respectively. Lipase obtained using the constitutive promoter showed the highest activity of 18.8 U/mg in 3 days of cultivation time. Optimal lipase activity was observed at pH 7.0 and 35 °C using p-nitrophenyl laurate as the substrate. Lipase activity was enhanced by Mn2+, Ba2+, Li+, Ca2+, Ni2+, CHAPS and Triton X-100 but was inhibited by Hg2+, Ag+ and SDS. The addition of 10% v/v of octanol, p-xylene, hexane and isopropanol increased lipase activity. Cultivation of lipase-expressing P. pastoris under pGAP in synthetic wastewater containing 1% w/v palm oil resulted in degradation of 87% of the oil within 72 h. P. pastoris expressing F. solani lipase from constitutive expression system has the potential to be used as an alternative microorganism for lipid degradation.

Dual bioimprinting of Thermomyces lanuginosus lipase for synthesis of biodiesel

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Joyeeta Mukherjee

2016-06-01

Full Text Available Use of biodiesel as an alternative to non-renewable sources of energy has become an attractive option in recent years. The enzymatic synthesis of biodiesel by transesterification of fats/oils with an alcohol is a much more sustainable route than the chemical method. However, cost effectiveness of the enzymatic route is a major barrier in its commercialization. In this work, a high activity biocatalyst design of Thermomyces lanuginosus lipase is made by dually bioimprinting it with substrate and a surfactant (which is believed to open up the lid covering the active site of the lipase during precipitation of the lipase in organic solvent. When the lipase was bioimprinted with only the surfactants, 28 U of the enzyme/g of oil could yield 99% biodiesel from soybean oil in about 4 h. However, when dually bioimprinted even very low enzyme load 1.4 U/g of oil, yielded 99% biodiesel within 48 h.

Pixel DAQ and trigger for HL-LHC

International Nuclear Information System (INIS)

Morettini, P.

2017-01-01

The read-out is one of the challenges in the design of a pixel detector for the High Luminosity upgrade of the Large Hadron Collider (HL-LHC), that is expected to operate from 2026 at a leveled luminosity of 5 × 10 34  cm −2  s −1 . This is especially true if tracking information is needed in a low latency trigger system. The difficulties of a fast read-out will be reviewed, and possible strategies explained. The solutions that are being evaluated by the ATLAS and CMS collaborations for the upgrade of their trackers will be outlined and ideas on possible development beyond HL-LHC will be presented.

Lipoprotein lipase and endothelial lipase in human testis and in germ cell neoplasms

DEFF Research Database (Denmark)

Nielsen, J E; Lindegaard, M L; Friis-Hansen, L

2009-01-01

. The results suggest that both EL and LPL participate in the supply of nutrients and steroidogenesis in the testes, and that especially EL may be important for the supply of cholesterol for testosterone production in the Leydig cells. The partial cellular separation of the expression of the two lipases...

HL-LHC alternatives

CERN Document Server

Tomás, R; White, S

2014-01-01

The HL-LHC parameters assume unexplored regimes for hadron colliders in various aspects of accelerator beam dynamics and technology. This paper reviews three alternatives that could potentially improve the LHC performance: (i) the alternative filling scheme 8b+4e, (ii) the use of a 200 MHz RF system in the LHC and (iii) the use of proton cooling methods to reduce the beam emittance (at top energy and at injection). The alternatives are assessed in terms of feasibility, pros and cons, risks versus benefits and the impact on beam availability.

Expected performance of tracking and vertexing with the HL-LHC ATLAS detector

CERN Document Server

Calace, Noemi; The ATLAS collaboration

2018-01-01

The High Luminosity LHC (HL-LHC) aims to increase the LHC data-set by an order of magnitude in order to increase its potential for discoveries. Starting from the middle of 2026, the HL-LHC is expected to reach the peak instantaneous luminosity of $7.5 \\cdot 10^{34} cm^{-2}s^{-1}$ which corresponds to about 200 inelastic proton-proton collisions per beam crossing. To cope with the large radiation doses and high pileup, the current ATLAS Inner Detector will be replaced with a new all-silicon Inner Tracker. In this talk the expected performance of tracking and vertexing with the HL-LHC tracker is presented. Comparison is made to the performance with the Run2 detector. Ongoing developments of the track reconstruction for the HL-LHC are also discussed.

Fat digestion by lingual lipase: mechanism of lipolysis in the stomach and upper small intestine.

Science.gov (United States)

Liao, T H; Hamosh, P; Hamosh, M

1984-05-01

Ten to 30% of dietary fat is hydrolyzed in the stomach by lingual lipase, an enzyme secreted from lingual serous glands. We investigated the substrate specificity of this enzyme as well as the potential of lingual lipase to act in the upper small intestine i.e., in the presence of bile salts and lecithin. The data presented show that partially purified preparations of rat lingual lipase and the lipase in gastric aspirates of newborn infants have identical substrate specificity: medium-chain triglycerides were hydrolyzed at rates 5-8-fold higher than long-chain triglycerides; the rat and human enzymes do not hydrolyze the ester bond of lecithin or cholesteryl-ester. In contrast to pancreatic lipase, the hydrolysis of triglycerides by lingual lipase is not inhibited by lecithin. But, similar to pancreatic lipase the activity of lingual lipase is inhibited by bile salts, the extent of inhibition varying with its nature and concentration. This inactivation is not prevented by colipase but is partially averted by lipids and protein, suggesting that lingual lipase can remain active in the duodenum. The pH optimum of the enzyme (2.2-6.5 in the rat and 3.5-6.0 in human gastric aspirates) is compatible with continued activity in the upper small intestine, especially during the neonatal period, when the luminal pH is under 6.5. The marked variation in lipase activity levels in gastric aspirates of newborn infants is probably due to individual variations in enzyme amounts. The characteristics of the lipase are however identical in infants with low, intermediate or high activity levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Lipase genes in Mucor circinelloides: identification, sub-cellular location, phylogenetic analysis and expression profiling during growth and lipid accumulation.

Science.gov (United States)

Zan, Xinyi; Tang, Xin; Chu, Linfang; Zhao, Lina; Chen, Haiqin; Chen, Yong Q; Chen, Wei; Song, Yuanda

2016-10-01

Lipases or triacylglycerol hydrolases are widely spread in nature and are particularly common in the microbial world. The filamentous fungus Mucor circinelloides is a potential lipase producer, as it grows well in triacylglycerol-contained culture media. So far only one lipase from M. circinelloides has been characterized, while the majority of lipases remain unknown in this fungus. In the present study, 47 potential lipase genes in M. circinelloides WJ11 and 30 potential lipase genes in M. circinelloides CBS 277.49 were identified by extensive bioinformatics analysis. An overview of these lipases is presented, including several characteristics, sub-cellular location, phylogenetic analysis and expression profiling of the lipase genes during growth and lipid accumulation. All of these proteins contained the consensus sequence for a classical lipase (GXSXG motif) and were divided into four types including α/β-hydrolase_1, α/β-hydrolase_3, class_3 and GDSL lipase (GDSL) based on gene annotations. Phylogenetic analyses revealed that class_3 family and α/β-hydrolase_3 family were the conserved lipase family in M. circinelloides. Additionally, some lipases also contained a typical acyltransferase motif of H-(X) 4-D, and these lipases may play a dual role in lipid metabolism, catalyzing both lipid hydrolysis and transacylation reactions. The differential expression of all lipase genes were confirmed by quantitative real-time PCR, and the expression profiling were analyzed to predict the possible biological roles of these lipase genes in lipid metabolism in M. circinelloides. We preliminarily hypothesized that lipases may be involved in triacylglycerol degradation, phospholipid synthesis and beta-oxidation. Moreover, the results of sub-cellular localization, the presence of signal peptide and transcriptional analyses of lipase genes indicated that four lipase in WJ11 most likely belong to extracellular lipases with a signal peptide. These findings provide a platform

The HL-LHC accelerator physics challenges

CERN Document Server

Fartoukh, S

2014-01-01

We review the conceptual baseline of the HL-LHC project, putting into perspective the main beam physics challenges of this new collider in comparison with the existing LHC, and the series of solutions and possible mitigation measures presently envisaged.

The HL-LHC Accelerator Physics Challenges

Science.gov (United States)

Fartoukh, S.; Zimmermann, F.

The conceptual baseline of the HL-LHC project is reviewed, putting into perspective the main beam physics challenges of this new collider in comparison with the existing LHC, and the series of solutions and possible mitigation measures presently envisaged.

The HL-LHC accelerator physics challenges

CERN Document Server

Fartoukh, S

2015-01-01

The conceptual baseline of the HL-LHC project is reviewed, putting into perspective the main beam physics challenges of this new collider in comparison with the existing LHC, and the series of solutions and possible mitigation measures presently envisaged.

Chicken fat and inorganic nitrogen source for lipase production by ...

African Journals Online (AJOL)

SAM

2014-03-19

Mar 19, 2014 ... for lipase production, the production cost was $US 518.00/million Units of lipase. Key words: ... energetics, fine chemicals and pulp and paper industries. ... for enzyme production is extremely important in dictating ... fat is waste product of poultry processing industry ... Economic Research Service,” 2013).

In silico modeling of lipase H | Jabeen | African Journal of ...

African Journals Online (AJOL)

LAH 2 is a type of autosomal recessive hypotrichosis that affect hairs, eyebrows, scalp and eyelashes. Mutations in Lipase H gene result in LAH 2. Changes that result from mutation on physiochemical properties, post-translational modifications, functional sites, secondary structure and tertiary structure lipase H gene (LIPH) ...

Effect of culture conditions on lipase production by Fusarium solani in batch fermentation.

Science.gov (United States)

Maia, M M; Heasley, A; Camargo de Morais, M M; Melo, E H; Morais, M A; Ledingham, W M; Lima Filho, J L

2001-01-01

Lipase (Glycerol ester hydrolase EC 3.1.1.3.) from a Brazilian strain of Fusarium solani FSI has been investigated. The effect of different carbon sources and trace elements added to basal medium was observed with the aim of improving enzyme production. Lipase specific activity was highest (0.45 U mg(-1)) for sesame oil. When this medium was supplemented with trace elements using olive oil, corn oil and sesame oil the lipase specific activity increased to 0.86, 1.89 and 1.64 U mg(-1), respectively, after 96 h cultivation without any considerable biomass increase. The Km of this lipase using pNPP (p-nitrophenylpalmitate) as substrate, was 1.8 mM with a Vmax of 1.7 micromol min(-1) mg protein(-1). Lipase activity increased in the presence of increasing concentrations of hexane and toluene. In contrast, incubation of this enzyme with water-soluble solvents decreased its activity after 10% concentration (v/v) of the solvent. The lipase activity was stable below 35 degrees C but above this temperature activity losses were observed.

Lipase From Thermoalkalophilic Pseudomonas species as an Additive in Potential Laundry Detergent Formulations

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Ibrahim, C. O.

2009-01-01

Full Text Available Lipase isolated from a thermoalkalophilic Pseudomonas species was used as additive to improve the degree of olive oil removal from cotton fabric in the presence of surfactants. The lipase used in this study was found to be more effective with non ionic surfactants as compared to ionic surfactants. In terms of stability, there was no decrease in activity found in the presence of Tween 85, Span 80 and Span 20. Lipase from Pseudomonas species was most active in the presence of Tween 85, Span 80 and Span 20. The application of lipase from Pseudomonas species as an additive in the formulation containing Span 80 has improved oil removal by 36% using the washing system consisting 5 U/mL lipase, at 70 °C for 20 min and 0.8% of Span 80 as surfactant. Considering that lipase from Pseudomonas species is stable in high pH and temperatures in the presence of various surfactants, therefore it is suitable to be incorporated as additives in potential detergent formulations.

Characterization and spray drying of lipase produced by the endophytic fungus Cercospora kikuchii

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T. A. Costa-Silva

2014-12-01

Full Text Available A lipase from the endophytic fungus Cercospora kikuchii was purified, biochemically characterized and the effects of spray drying on stabilization of the purified enzyme were studied. The lipase was purified 9.31-fold with recovery of 26.6% and specific activity of 223.6 U/mg. The optimum pH and temperature were 4.6 and 35 ºC, respectively, while the Vmax was 10.28 µmol/min.mg-1 protein and Km 0.0324 mM. All the metal ions tested enhanced the enzyme activity. The lipase retained almost 100% activity in the presence of strong oxidants and was also resistant to Triton X, Tween 80 and 20 and SDS, as well as to proteases. The purified lipase was spray dried and kept until 85.2% of enzymatic activity. At least 70% of the enzymatic activity was maintained for spray dried purified lipase during the storage period. The lipase produced by Cercospora kikuchii has properties useful for industrial application and showed adequate stabilization and retention of its enzymatic activity after spray drying.

Lipase-catalyzed biodiesel synthesis with different acyl acceptors

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Ognjanović Nevena D.

2008-01-01

Full Text Available Biodiesel is an alternative fuel for diesel engine that is environmentally acceptable. Conventionally, biodiesel is produced by transesterification of triglycerides and short alcohols in the presence of an acid or an alkaline catalyst. There are several problems associated with this kind of production that can be resolved by using lipase as the biocatalyst. The aim of the present work was to investigate novel acyl acceptors for biodiesel production. 2-Propanol and n-butanol have a less negative effect on lipase stability, and they also improve low temperature properties of the fuel. However, excess alcohol leads to inactivation of the enzyme, and glycerol, a major byproduct, can block the immobilized enzyme, resulting in low enzymatic activity. This problem was solved by using methyl acetate as acyl acceptor. Triacetylglycerol is produced instead of glycerol, and it has no negative effect on the activity of the lipase.

Dependence of PERT endpoint on endogenous lipase activity.

Science.gov (United States)

Gao, Wen-Yi; Mulberg, Andrew E

2014-11-01

To clarify and to understand the potential for misinterpretation of change in fecal fat quantitation during pancreatic enzyme replacement therapy (PERT) trials for treatment of exocrine pancreatic insufficiency. Analysis of clinical trials submitted to the U.S. Food and Drug Administration (FDA) for approval of PERT that enrolled 123 cystic fibrosis adult and pediatric patients treated with Creon, Pertzye, Ultresa, and Zenpep. The CFA% defines lipase activity as a percentage of converting substrate of "Total Daily Dietary Fat Intake." PERT trials performed to date have modified the definition to converting the "Shared Daily Fat Intake," generating "Partial CFA" for the exogenous lipase: the higher the activity of coexisting endogenous lipase, the lower the "Partial CFA" of exogenous measured. This review shows that "Partial CFA" is not CFA. Enrollment of patients with low HPLA during treatment may improve the interpretability of "Partial CFA" measured by PERT trials.

Novel magnetic cross-linked lipase aggregates for improving the resolution of (R, S)-2-octanol.

Science.gov (United States)

Liu, Ying; Guo, Chen; Liu, Chun-Zhao

2015-03-01

Novel magnetic cross-linked lipase aggregates were fabricated by immobilizing the cross-linked lipase aggregates onto magnetic particles with a high number of -NH2 terminal groups using p-benzoquinone as the cross-linking agent. At the optimal fabrication conditions, 100% of immobilization efficiency and 139% of activity recovery of the magnetic cross-linked lipase aggregates were achieved. The magnetic cross-linked lipase aggregates were able to efficiently resolve (R, S)-2-octanol, and retained 100% activity and 100% enantioselectivity after 10 cycles of reuse, whereas the cross-linked lipase aggregates only retained about 50% activity and 70% enantioselectivity due to insufficient cross-linking. These results provide a great potential for industrial applications of the magnetic cross-linked lipase aggregates. © 2014 Wiley Periodicals, Inc.

Novel One-Pot Green Synthesis of Indolizines Biocatalysed by Candida antarctica Lipases

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Simon Bonte

2013-02-01

Full Text Available Marine microorganisms are of considerable interest as a promising source of enzymes with unsuspected potentials as catalysts for chemical synthesis. We describe here an efficient method for one-pot indolizine synthesis that has been developed using lipase A and lipase B from Candida antarctica as biocatalysts. As showed by HPLC/MS analysis, the yield in indolizines was higher in the presence of the biocatalyst than in absence of enzyme. Lipase A, from Candida antarctica, showed high catalytic activity and selectivity for the cycloaddition reactions. When the reactions were performed under ultrasound irradiation, the Candida antarctica lipase catalyzed reactions yielded pure indolozines, in good yields and in very short time.

Isolation of furocoumarins from bergamot fruits as HL-60 differentiation-inducing compounds.

Science.gov (United States)

Kawaii, S; Tomono, Y; Katase, E; Ogawa, K; Yano, M

1999-10-01

The HL-60 differentiation-inducing compounds in bergamot fruits were isolated with column chromatography and identified as bergamottin, bergapten, and citropten by (1)H and (13)C NMR. Their HL-60 differentiation-inducing activity was measured by examining nitro blue tetrazolium (NBT) reducing, nonspecific acid esterase (NSE), specific esterase (SE), and phagocytic activities, and bergamottin showed the strongest activity among the coumarins isolated from bergamot fruits. The structure-activity relationship obtained from HL-60 differentiation assay suggests that hydrophobicity of furocoumarins is correlated with their activity.

Synthesis activity-based zymography for detection of lipases and esterases.

Science.gov (United States)

Kwon, Min-A; Kim, Hyun Suk; Hahm, Dae-Hyun; Song, Jae Kwang

2011-04-01

A new zymography method for lipases and esterases was developed on the basis of the esterification reaction between fatty acids and alcohols. The enzymes were separated by SDS-PAGE and native PAGE. The gel was washed and then incubated in an aqueous solution containing fatty acids (oleic acid 18:1 or caprylic acid 8:0) and dodecanol. Synthesis was visualized by in situ precipitation of water-insoluble and non-diffusible fatty acid esters, such as dodecyl oleate and dodecyl octanoate. The synthesis activity-based zymography was confirmed with different enzyme samples, including commercial lipase preparations, purified recombinant lipase and cutinase, and crude culture supernatants of lipolytic enzyme-producing soil bacteria.

Transesterification Synthesis of Chloramphenicol Esters with the Lipase from Bacillus amyloliquefaciens

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Fengying Dong

2017-09-01

Full Text Available This work presents a synthetic route to produce chloramphenicol esters by taking advantage the high enantio- and regio-selectivity of lipases. A series of chloramphenicol esters were synthesized using chloramphenicol, acyl donors of different carbon chain length and lipase LipBA (lipase cloned from Bacillus amyloliquefaciens. Among acyl donors with different carbon chain lengths, vinyl propionate was found to be the best. The influences of different organic solvents, reaction temperature, reaction time, enzyme loading and water content on the synthesis of the chloramphenicol esters were studied. The synthesis of chloramphenicol propionate (0.25 M with 4.0 g L−1 of LipBA loading gave a conversion of ~98% and a purity of ~99% within 8 h at 50 °C in 1,4-dioxane as solvent. The optimum mole ratio of vinyl propionate to chloramphenicol was increased to 5:1. This is the first report of B. amyloliquefaciens lipase being used in chloramphenicol ester synthesis and a detailed study of the synthesis of chloramphenicol propionate using this reaction. The high enzyme activity and selectivity make lipase LipBA an attractive catalyst for green chemical synthesis of molecules with complex structures.

Influence of cosolvents on the hydrophobic surface immobilization topography of Candida antarctica lipase B

Science.gov (United States)

The presence of cosolvents and co-solutes during the immobilization of lipases on hydrophobic supports may influence the extent of lipase immobilization and the long-term catalytic stability of the biocatalyst. Candida antarctica B lipase immobilization was examined on a hydrophobic surface, i.e., ...

HL-LHC kicker magnet (MKI)

CERN Multimedia

Brice, Maximilien

2018-01-01

HL-LHC kicker magnet (MKI): last vacuum test, preparation for transport to LHC transfer line in underground tunnel.The LHC injection kicker systems (MKIs) generate fast field pulses to inject the clockwise rotating beam at Point 2 and the anti-clockwise rotating beam at Point 8: there are eight MKI magnets installed in total. Each MKI magnet contains a high purity alumina tube: if an MKI magnet is replaced this tube requires conditioning with LHC beam: until it is properly conditioned, there can be high vacuum pressure due to the beam. This high pressure can also cause electrical breakdowns in the MKI magnets. A special coating (Cr2O3) has been applied to the inside of the alumina tube of an upgraded MKI magnet – this is expected to greatly reduce the pressure rise with beam. In addition, HL-LHC beam would result in excessive heating of the MKI magnets: the upgraded design includes modifications that will reduce heating, and move the power deposition to parts that will be easier to cool. Experience during 2...

Cloning and characterization of newly isolated lipase from Enterobacter sp. Bn12.

Science.gov (United States)

Farrokh, Parisa; Yakhchali, Bagher; Karkhane, Ali Asghar

2014-01-01

A mesophilic Enterobacter sp. Bn12 producing an alkaline thermostable lipase was isolated from soil in Tehran, Iran. The lipase gene (ELBn12) was identified from a genomic library. Sequence analysis of the DNA fragment revealed an open reading frame of 879 bp encoding a lipase with a molecular mass of 31.3 kDa. The deduced amino acid sequence showed 96% identity with a lipase of Enterobacter sp. Ag1 and the identity of their DNA sequences was 88.9%. ELBn12 belongs to the lipase subfamily I.1 and its catalytic triad consists of Ser82, Asp237 and His259. The lipase was expressed in Escherichia coli (BL21) pLysS and partially purified by anion exchange chromatography. The maximum activity of ELBn12 was obtained at temperature of 60 °C and pH 8.0 towards tricaprylin (C8) and its specific activity was around 2900 U/mg. ELBn12 was stable within a broad pH range from 6.0 to 11.0. The enzyme showed high stability in both polar and nonpolar organic solvents at 50% (v/v). The lipase activity was enhanced in the presence of 10 mM of Ca(2+), Mg(2+) and K(+), while heavy metals (Fe(3+) and Zn(2+)) had strong inhibitory effect. ELBn12 showed high activity in the presence of 1% (w/v) nonionic surfactants, however ionic surfactants inhibited the lipolytic activity. ELBn12 characteristics show that it has a potential to be used in various industrial processes.

A newly high alkaline lipase: an ideal choice for application in detergent formulations

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Cherif Slim

2011-11-01

Full Text Available Abstract Background Bacterial lipases received much attention for their substrate specificity and their ability to function in extreme environments (pH, temperature.... Many staphylococci produced lipases which were released into the culture medium. Reports of thermostable lipases from Staphylococcus sp. and active in alkaline conditions are not previously described. Results A newly soil-isolated Staphylococcus sp. strain ESW secretes an induced lipase in the culture medium. The effects of temperature, pH and various components in a detergent on the activity and stability of Staphylococcus sp. lipase (SL1 were studied in a preliminary evaluation for use in detergent formulation solutions. The enzyme was highly active over a wide range of pH from 9.0 to 13.0, with an optimum at pH 12.0. The relative activity at pH 13.0 was about 60% of that obtained at pH 12.0. It exhibited maximal activity at 60°C. This novel lipase, showed extreme stability towards non-ionic and anionic surfactants after pre-incubation for 1 h at 40°C, and relative stability towards oxidizing agents. Additionally, the crude enzyme showed excellent stability and compatibility with various commercial solid and liquid detergents. Conclusions These properties added to the high activity in high alkaline pH make this novel lipase an ideal choice for application in detergent formulations.

Improved Performance of Pseudomonas fluorescens lipase by covalent immobilization onto Amberzyme

NARCIS (Netherlands)

Aslan, Yakup; Handayani, Nurrahmi; Stavila, Erythrina; Loos, Katja

2013-01-01

Objective: In this study, the conditions of covalent immobilization of Pseudomonas fluorescens lipase onto an oxirane-activated support (Amberzyme) were optimized to obtain a high activity yield. Furthermore, the operational and storage stabilities of immobilized lipase were tested. Methods: Optimum

Production of extracellular lipase by the phytopathogenic fungus Fusarium solani FS1 Produção de lipase extracelular pelo fungo fitopatogênico Fusarium solani FS1

OpenAIRE

Maria de Mascena Diniz Maia; Marcia Maria Camargo de Morais; Marcos Antonio de Morais Jr.; Eduardo Henrique Magalhães Melo; José Luiz de Lima Filho

1999-01-01

A Brazilian strain of Fusarium solani was tested for extracellular lipase production in peptone-olive oil medium. The fungus produced 10,500 U.l-1 of lipase after 72 hours of cultivation at 25oC in shake-flask at 120 rpm in a medium containing 3% (w/v) peptone plus 0.5% (v/v) olive oil. Glucose (1% w/v) was found to inhibit the inductive effect of olive oil. Peptone concentrations below 3% (w/v) resulted in a reduced lipase production while increased olive oil concentration (above 0.5%) did n...

An experimental study on cerebral ischemic penumbra imaging with 99Tcm-HL91

International Nuclear Information System (INIS)

Zhu Cansheng; Jiang Ningyi

2002-01-01

Objective: To investigate the biodistribution of 99 Tc m -4,9-diaza-3,3,10,10-tetramethyl dodecan-2,11-dione dioxime (HL91) in rat model of middle cerebral artery occlusion (MCAO). Methods: Thirty-one MCAO rats were established. Fourteen rats were used to study the biodistribution of 99 Tc m -HL91 and 15 rats were used to study the distribution of 99 Tc m -HL91 in the brain of MCAO model rats. Autoradiographic study of brain was also done in 16 MCAO model rats. Results: The liver and kidney retention were higher than that in other tissues. At 1 h after injection, small intestine retention was also high. But radioactivity in normal brain was low. Retention in target site was higher than that in non-target site. Difference between subgroups of operation and that of pseudo operation was significant (P 99 Tc m -HL91 at the target-ischemic area was shown in the autoradiograph. By using computer-enhanced image analysis, difference between target site and non-target site in the same autoradiograph and the differences between operation subgroups and that of pseudo-subgroups were all significant via Dunnett t-test and One-Way ANOVA. Conclusions: 99 Tc m -HL91 can be avidly taken up by ischemic penumbra and target/non-target ratio is high. 99 Tc m -HL91 is a potential agent for hypoxic tissue imaging, and 99 Tc m -HL91 SPECT is a promising modality in detecting the ischemic penumbra

Application of 99Tcm-HL-91 in the hypoxia study of malignant lymphoma

International Nuclear Information System (INIS)

Li Li; Han Peizhen; Yan Yujun; Wang Yueying; Wang Junqi; Li Meijia

2002-01-01

Objective: 99 Tc m -HL91 is a putative hypoxic tracer probing hypoxia in solid tumors. This study was aimed at investigating the property of the spontaneous IRM-2-ML malignant lymphoma in homozygotic IRM-2 mice, and at testing the applicability of 99 Tc m -HL91 to the imaging of hypoxia in tumors. Methods: Biodistribution of 99 Tc m -HL91 after intravenously injection into normal and tumor-bearing IRM-2 mice was studied by determining blood and tissue levels of radioactivity from 20 to 360 min after injection. Nicotinamide was used to reduce the extent of hypoxia in the tumors. Planar SPECT imaging on normal and tumor-bearing IRM-2 mice was also performed. Results: Tumor load did not significantly influence the retention of 99 Tc m -HL91 in normal organs. 99 Tc m -HL91 was metabolized mainly via the liver and kidney, and was cleared fast from the blood. The tumor-to-blood ratio and tumor-to-muscle ratio continued to increase until 360 min (2.63 +- 0.25 and 3.37 +- 0.22 at 120 min, 3.51 +- 0.17 and 6.44 +- 0.29 at 360 min, respectively). The retention of 99 Tc m -HL91 in the tumor was reduced in mice by treatment with nicotinamide. Planar SPECT imaging showed that tumor could be observed clearly. Conclusion: These results confirm that IRM-2-ML malignant lymphoma possesses the common property of solid tumors,and also indicate that 99 Tc m -HL91 could be used to detect tumor hypoxia

Effect of citrus flavonoids on HL-60 cell differentiation.

Science.gov (United States)

Kawaii, S; Tomono, Y; Katase, E; Ogawa, K; Yano, M

1999-01-01

Twenty-seven Citrus flavonoids were examined for their activity of induction of terminal differentiation of human promyelocytic leukemia cells (HL-60) by nitro blue tetrazolium (NBT) reducing, nonspecific esterase, specific esterase, and phagocytic activities. 10 flavonoids were judged to be active (percentage of NBT reducing cells was more than 40% at a concentration of 40 microM), and the rank order of potency was natsudaidain, luteolin, tangeretin, quercetin, apigenin, 3, 3, '4, '5, 6, 7, 8-heptamethoxyflavone, nobiletin, acacetin, eriodictyol, and taxifolin. These flavonoids exerted their activity in a dose-dependent manner. HL-60 cells treated with these flavonoids differentiated into mature monocyte/macrophage. The structure-activity relationship established from comparison between flavones and flavanones revealed that ortho-catechol moiety in ring B and C2-C3 double bond had an important role for induction of differentiation of HL-60. In polymethoxylated flavones, hydroxyl group at C3 and methoxyl group at C8 enhanced the differentiation-inducing activity.

Modification of steel 35 HL surge current during crystallization

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Zhbanova O.M.

2017-04-01

Full Text Available The method of electro steel melt modification 35 HL variable polarity current pulses with a duration of more 10-3s frequency within the 5–33 Hz, 5–24 porosity meanders, strength 30–40 A at a voltage of 180–240 V during crystallization, which allows to obtain high-quality castings 35 HL steel grade. Show that electro melt processing improves the structure and reduces the physical heterogeneity of castings and increases the rate of dissolution of metallic impurities and other components in the melt, providing fine-grained structure and increases the homogeneity of metal carbides reduces the amount of manganese reduces gases and nonmetallic inclusions. Modifying steel 35 HL pulse current during crystallization of the melt increases the physical and mechanical properties of tempered steel, increasing yield strength by 30 %, the tensile strength at 7 % elongation of 1,5 % relative narrowing by 2 %, toughness at 20 %.

Direct solid phase radioimmunoassay for chicken lipoprotein lipase

International Nuclear Information System (INIS)

Cheung, A.H.; Bensadoun, A.; Cheng, C.

1979-01-01

A direct, noncompetitive immunoassay for chicken lipoprotein lipase (LPL) was developed. Antibodies to LPL were purified by immunoadsorption chromatography of goat antisera on an LPL-Sepharose column. Purified anti-LPL immunoglobulins were coupled covalently to hydrophilic polyacrylamide beads by a carbodiimide reagent. An excess amount of these beads was incubated with the sample on the standard to be assayed. The amount of LPL immobilized by the heads was then detected by an excess amount of 125 I-labeled anti-LPL immunoglobulin. A linear relationship was obtained between the radioactivity bound and the amount of highly purified LPL used as a standard. The range of the assay was from 0.1 to 1.1 ng PLP. The assay was specific for chicken LPL and showed no cross-reactivity with liver lipase. It does not distinguish heat-inactivated from catalytically active enzyme species. This assay should be useful in studies of lipoprotein lipase where both catalytic activity and enzyme mass need to be quantitated

Effect of Ascorbic Acid on Lipoprotein Lipase Activity | Kotze | South ...

African Journals Online (AJOL)

Baboons kept on hypovitaminotic C diets, but without clinical signs of scurvy, had significantly higher heart muscle lipoprotein lipase activity than baboons on vitamin C 34 mg/kg body mass/day. When the serum vitamin C levels were above 0,35 mg/100 ml the heart muscle lipoprotein lipase was repressed. Serum vitamin C ...

Down-regulation of procaspase-8 expression by focal adhesion kinase protects HL-60 cells from TRAIL-induced apoptosis

International Nuclear Information System (INIS)

Tamagiku, Yuji; Sonoda, Yoshiko; Kunisawa, Mari; Ichikawa, Daiju; Murakami, Yayoi; Aizu-Yokota, Eriko; Kasahara, Tadashi

2004-01-01

We have demonstrated that focal adhesion kinase (FAK)-overexpressed (HL-60/FAK) cells have marked resistance against various apoptotic stimuli such as hydrogen peroxide, etoposide, and ionizing radiation compared with the vector-transfected (HL-60/Vect) cells. HL-60/FAK cells are highly resistant to TRAIL-induced apoptosis, while original HL-60 or HL-60/Vect cells were sensitive. TRAIL at 500 ng/ml induced significant DNA fragmentation, activation of caspase-8 and 3, the processing of a proapoptotic BID, and mitochondrial release of cytochrome c in HL-60/Vect cells, whereas no such events were observed in the HL-60/FAK cells. In particular, the expression of procaspase-8 gene and subsequent cleavage of caspase-8 were markedly reduced in HL-60/FAK cells, while expression of TRAIL-receptor 2 and 3, TRADD, and FADD was equivalent in both types of cells. In HL-60/FAK cells, the phosphoinositide 3 (PI3)-kinase/Akt survival pathway was constitutively activated, accompanied by significant induction of inhibitor-of-apoptosis proteins, XIAP, RIP, and Bcl-XL. The introduction of FAK siRNA in HL-60/FAK cells sensitized them against TRAIL-induced apoptosis, confirming that overexpressed FAK downregulates procaspase-8 expression, which subsequently inhibits downstream apoptosis pathway in the HL-60/FAK cells

Oral lipase activities and fat-taste receptors for fat-taste sensing in chickens.

Science.gov (United States)

Kawabata, Yuko; Kawabata, Fuminori; Nishimura, Shotaro; Tabata, Shoji

2018-01-01

It has been reported that a functional fat-taste receptor, GPR120, is present in chicken oral tissues, and that chickens can detect fat taste in a behavioral test. However, although triglycerides need to be digested to free fatty acids to be recognized by fat-taste receptors such as GPR120, it remains unknown whether lipase activities exist in chicken oral tissues. To examine this question, we first cloned another fat-taste receptor candidate gene, CD36, from the chicken palate. Then, using RT-PCR, we determined that GPR120 and CD36 were broadly expressed in chicken oral and gastrointestinal tissues. Also by RT-PCR, we confirmed that several lipase genes were expressed in both oral and gastrointestinal tissues. Finally, we analyzed the lipase activities of oral tissues by using a fluorogenic triglyceride analog as a lipase substrate. We found there are functional lipases in oral tissues as well as in the stomach and pancreas. These results suggested that chickens have a basic fat-taste reception system that incorporates a triglycerides/oral-lipases/free fatty acids/GPR120 axis and CD36 axis. Copyright © 2017 Elsevier Inc. All rights reserved.

Improvement of lipase production from Geotrichum sp. in shaken flasks

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Maldonadoa Resende Rafael

2012-01-01

Full Text Available This work is focused on the study of different variables on inoculum build-up aiming to improve the lipase production by Geotrichum sp. by means a sequential strategy of experimental design. The effects of inoculum size, corn steep liquor concentration, volume of inoculum, pH of medium, age of inoculum and soybean oil concentration on lipase activity were assessed by means of two factorial experimental designs. A maximum lipase activity of 35.20±0.8 U/mL was obtained with a inoculum composed of one circular area of 0.78cm2 containing spores, 50 mL of inoculum volume medium, 12 hours of inoculum age, 15% w/v of corn steep liquor concentration, 1.0%w/v of soybean oil concentration and initial pH 5.0 at 30°C and 150 rpm in flasks. This work showed that an enhancement of lipase activity can be obtained using a sequential statistical factorial approach to define the variables for inoculum build-up.

Lipase-Secreting Bacillus Species in an Oil-Contaminated Habitat: Promising Strains to Alleviate Oil Pollution

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Li Pin Lee

2015-01-01

Full Text Available Lipases are of great interest for different industrial applications due to their diversity and versatility. Among different lipases, microbial lipases are preferable due to their broad substrate specificity, and higher stability with lower production costs compared to the lipases from plants and animals. In the past, a vast number of bacterial species have been reported as potential lipases producers. In this study, the lipases-producing bacterial species were isolated from an oil spillage area in the conventional night market. Isolated species were identified as Bacillus species by biochemical tests which indicate their predominant establishment, and further screened on the agar solid surfaces using lipid and gelatin as the substrates. Out of the ten strains tested, four potential strains were subjected to comparison analysis of the lipolytic versus proteolytic activities. Strain 10 exhibited the highest lipolytic and proteolytic activity. In all the strains, the proteolytic activity is higher than the lipolytic activity except for strain 8, suggesting the possibility for substrate-based extracellular gene induction. The simultaneous secretion of both the lipase and protease is a mean of survival. The isolated bacterial species which harbour both lipase and protease enzymes could render potential industrial-based applications and solve environmental issues.

Polyethyleneimine-modified superparamagnetic Fe3O4 nanoparticles for lipase immobilization: Characterization and application

International Nuclear Information System (INIS)

Khoobi, Mehdi; Motevalizadeh, Seyed Farshad; Asadgol, Zahra; Forootanfar, Hamid; Shafiee, Abbas; Faramarzi, Mohammad Ali

2015-01-01

Magnetically separable nanospheres consisting of polyethyleneimine (PEI) and succinated PEI grafted on silica coated magnetite (Fe 3 O 4 ) were prepared and characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, vibrating sample magnetometer, scanning electron microscopy and transmission electron microscopy. The prepared magnetic nanoparticles were then applied for physical adsorption or covalent attachment of Thermomyces lanuginosa lipase (TLL) via glutaraldehyde or hexamethylene diisocyanate. The reusability, storage, pH and thermal stabilities of the immobilized enzymes compared to that of free lipase were examined. The obtained results showed that the immobilized lipase on MNPs@PEI-GLU was the best biocatalyst which retained 80% of its initial activity after 12 cycles of application. The immobilized lipase on the selected support (MNPs@PEI-GLU) was also applied for the synthesis of ethyl valerate. Following 24 h incubation of the immobilized lipase on the selected support in n-hexane and solvent free media, the esterification percentages were 72.9% and 28.9%, respectively. - Graphical abstract: A schematic of the preparation of PEI- and succinated PEI-grafted Fe 3 O 4 MNPs (MNPs@PEI) and the immobilization of lipase by covalent bonding and adsorption. - Highlights: • Functionalized polyethylenimine-grafted magnetic nanoparticles were synthesized. • The prepared supports were fully characterized by various analysis methods. • Lipase was immobilized on the nanostructures by adsorption and covalent attachment. • Immobilized lipase produced ethyl valerate in solvent free medium

Aplicação de lipase e monoglicerídeo em pão de forma enriquecido com fibras Application of lipase and monoglyceride in fiber enriched pan bread

Directory of Open Access Journals (Sweden)

Kelly Moreira Gandra

2008-03-01

Full Text Available Neste trabalho, estudou-se a aplicação da enzima lipase e do emulsificante monoglicerídeo em pão de forma enriquecido com fibras, com o objetivo de verificar a possibilidade de substituição do emulsificante pela enzima. Inicialmente, foi realizada a caracterização das matérias-primas principais (farinha e farelo de trigo. Os pães de forma foram elaborados pelo método de massa direta. Foi utilizado um planejamento experimental do tipo composto central rotacional com duas variáveis independentes: i dosagem de lipase; e ii dosagem de monoglicerídeo e, paralelamente, realizou-se um teste controle (sem adição de lipase e monoglicerídeo para comparação. As variáveis dependentes foram as características de qualidade dos pães: i volume específico; ii aceitação sensorial (aparência, textura, aroma e sabor; e iii vida de prateleira avaliada pela umidade do miolo e firmeza dos pães após 1, 4 e 7 dias do forneamento. Dentro das faixas estudadas, foi possível verificar que somente a umidade dos pães no quarto e sétimo dia após o processamento foi influenciada pela variação das dosagens de lipase e monoglicerídeo. Na avaliação sensorial, verificou-se que as notas médias atribuídas aos pães do teste controle foram inferiores à menor nota média dos ensaios do planejamento experimental, com exceção do sabor e aroma. Como não foi possível obter modelos matemáticos para todas as respostas, foram selecionados os ensaios 5 (1% monoglicerídeo, 7 (25 ppm lipase e 9 (25 ppm lipase e 1% monoglicerídeo do planejamento experimental, e o teste controle, para a avaliação dos resultados por análise de variância. Nas condições em que os ensaios foram conduzidos e para as faixas de lipase (0 a 50 ppm e monoglicerídeo (0 a 2% estudadas, verificou-se a possibilidade de substituir o monoglicerídeo por lipase em formulação de pão de forma enriquecido com fibras.In this work, the application of lipase and monoglyceride in

Enzymatic Production of FAME Biodiesel with Soluble Lipases

DEFF Research Database (Denmark)

T. Gundersen, Maria; Heltborg, Carsten Kirstejn; Yang, V

Biodiesel is a viable alternative to fossil fuels, and biocatalysis is gaining interest as a greener process. We focus on converting oils to Fatty Acid Methyl Ester (FAME) using soluble lipases, which offer an advantage compared to immobilized enzymes by cost efficiency and ease of implementation...... the defined operating space concerning: temperature, water content, initial methanol concentration and enzyme content. The identified optimum range was experimentally evaluated, and model findings were confirmed. Another barrier in lipase use in biodiesel production is the higher melting point (m...

New ether-functionalized ionic liquids for lipase-catalyzed synthesis of biodiesel.

Science.gov (United States)

Zhao, Hua; Song, Zhiyan; Olubajo, Olarongbe; Cowins, Janet V

2010-09-01

Ionic liquids (ILs) are being explored as solvents for the enzymatic methanolysis of triglycerides. However, most available ILs (especially hydrophobic ones) have poor capability in dissolving lipids, while hydrophilic ILs tend to cause enzyme inactivation. Recently, we synthesized a new type of ether-functionalized ionic liquids (ILs) carrying anions of acetate or formate; they are capable of dissolving a variety of substrates and are also lipase-compatible (Green Chem., 2008, 10, 696-705). In the present study, we carried out the lipase-catalyzed transesterifications of Miglyol oil 812 and soybean oil in these novel ILs. These ILs are capable of dissolving oils at the reaction temperature (50 degrees C); meanwhile, lipases maintained high catalytic activities in these media even in high concentrations of methanol (up to 50% v/v). High conversions of Miglyol oil were observed in mixtures of IL and methanol (70/30, v/v) when the reaction was catalyzed by a variety of lipases and different enzyme preparations (free and immobilized), especially with the use of two alkylammonium ILs 2 and 3. The preliminary study on the transesterification of soybean oil in IL/methanol mixtures further confirms the potential of using oil-dissolving and lipase-stabilizing ILs in the efficient production of biodiesels.

A quantitative assay measuring the function of lipase maturation factor 1

Science.gov (United States)

Yin, Fen; Doolittle, Mark H.; Péterfy, Miklós

2009-01-01

Newly synthesized lipoprotein lipase (LPL) and related members of the lipase gene family require an endoplasmic reticulum maturation factor for attainment of enzyme activity. This factor has been identified as lipase maturation factor 1 (Lmf1), and mutations affecting its function and/or expression result in combined lipase deficiency (cld) and hypertriglyceridemia. To assess the functional impact of Lmf1 sequence variations, both naturally occurring and induced, we report the development of a cell-based assay using LPL activity as a quantitative reporter of Lmf1 function. The assay uses a cell line homozygous for the cld mutation, which renders endogenous Lmf1 nonfunctional. LPL transfected into the mutant cld cell line fails to attain activity; however, cotransfection of LPL with wild-type Lmf1 restores its ability to support normal lipase maturation. In this report, we describe optimized conditions that ensure the detection of a complete range of Lmf1 function (full, partial, or complete loss of function) using LPL activity as the quantitative reporter. To illustrate the dynamic range of the assay, we tested several novel mutations in mouse Lmf1. Our results demonstrate the ability of the assay to detect and analyze Lmf1 mutations having a wide range of effects on Lmf1 function and protein expression. PMID:19471043

Stereoselectivity of Mucorales lipases toward triradylglycerols--a simple solution to a complex problem.

Science.gov (United States)

Scheib, H.; Pleiss, J.; Kovac, A.; Paltauf, F.; Schmid, R. D.

1999-01-01

The lipases from Rhizopus and Rhizomucor are members of the family of Mucorales lipases. Although they display high sequence homology, their stereoselectivity toward triradylglycerols (sn-2 substituted triacylglycerols) varies. Four different triradylglycerols were investigated, which were classified into two groups: flexible substrates with rotatable O'-C1' ether or ester bonds adjacent to C2 of glycerol and rigid substrates with a rigid N'-C1' amide bond or a phenyl ring in sn-2. Although Rhizopus lipase shows opposite stereopreference for flexible and rigid substrates (hydrolysis in sn-1 and sn-3, respectively), Rhizomucor lipase hydrolyzes both groups of triradylglycerols preferably in sn-1. To explain these experimental observations, computer-aided molecular modeling was applied to study the molecular basis of stereoselectivity. A generalized model for both lipases of the Mucorales family highlights the residues mediating stereoselectivity: (1) L258, the C-terminal neighbor of the catalytic histidine, and (2) G266, which is located in a loop contacting the glycerol backbone of a bound substrate. Interactions with triradylglycerol substrates are dominated by van der Waals contacts. Stereoselectivity can be predicted by analyzing the value of a single substrate torsion angle that discriminates between sn-1 and sn-3 stereopreference for all substrates and lipases investigated here. This simple model can be easily applied in enzyme and substrate engineering to predict Mucorales lipase variants and synthetic substrates with desired stereoselectivity. PMID:10210199

High-level expression and characterization of a chimeric lipase from Rhizopus oryzae for biodiesel production.

Science.gov (United States)

Yu, Xiao-Wei; Sha, Chong; Guo, Yong-Liang; Xiao, Rong; Xu, Yan

2013-02-21

Production of biodiesel from non-edible oils is receiving increasing attention. Tung oil, called "China wood oil" is one kind of promising non-edible biodiesel oil in China. To our knowledge, tung oil has not been used to produce biodiesel by enzymatic method. The enzymatic production of biodiesel has been investigated extensively by using Rhizopus oryzae lipase as catalyst. However, the high cost of R. oryzae lipase remains a barrier for its industrial applications. Through different heterologous expression strategies and fermentation techniques, the highest expression level of the lipase from R. oryzae reached 1334 U/mL in Pichia pastoris, which is still not optimistic for industry applications. The prosequence of lipases from Rhizopus sp. is very important for the folding and secretion of an active lipase. A chimeric lipase from R. oryzae was constructed by replacing the prosequence with that from the R. chinensis lipase and expressed in P. pastoris. The maximum activity of the chimera reached 4050 U/mL, which was 11 fold higher than that of the parent. The properties of the chimera were studied. The immobilized chimera was used successfully for biodiesel production from tung oil, which achieved higher FAME yield compared with the free chimeric lipase, non-chimeric lipase and mature lipase. By response surface methodology, three variables, water content, methanol to tung oil molar ratio and enzyme dosage were proved to be crucial parameters for biosynthesis of FAME and the FAME yield reached 91.9±2.5% at the optimized conditions by adding 5.66 wt.% of the initial water based on oil weight, 3.88 of methanol to tung oil molar ratio and 13.24 wt.% of enzyme concentration based on oil weight at 40°C. This is the first report on improving the expression level of the lipase from R. oryzae by replacing prosequences. The immobilized chimera was used successfully for biodiesel production from tung oil. Using tung oil as non-edible raw material and a chimeric lipase

Inhibition of pancreatic lipase and amylase by extracts of different spices and plants.

Science.gov (United States)

Sellami, Mohamed; Louati, Hanen; Kamoun, Jannet; Kchaou, Ali; Damak, Mohamed; Gargouri, Youssef

2017-05-01

The aim of this study is to search new anti-obesity and anti-diabetic agents from plant and spices crude extracts as alternative to synthetic drugs. The inhibitory effect of 72 extracts was evaluated, in vitro, on lipase and amylase activities. Aqueous extracts of cinnamon and black tea exhibited an appreciable inhibitory effect on pancreatic amylase with IC 50 values of 18 and 87 μg, respectively. Aqueous extracts of cinnamon and mint showed strong inhibitory effects against pancreatic lipase with IC 50 of 45 and 62 μg, respectively. The presence of bile salts and colipase or an excess of interface failed to restore the lipase activity. Therefore, the inhibition of pancreatic lipase, by extracts of spices and plants, belongs to an irreversible inhibition. Crude extract of cinnamon showed the strongest anti-lipase and anti-amylase activities which offer a prospective therapeutic approach for the management of diabetes and obesity.

Multi-channel time-division integrator in HL-2A

International Nuclear Information System (INIS)

Yan Ji

2008-01-01

HL-2A is China's first Tokamak device with divertor configuration (magnetic confinement controlled nuclear fusion device). To find out the details of on-going fusion reaction at different times is of important significance in achieving controlled nuclear fusion. We developed a new type multi-channel time-division integrator for HL-2A. It has functions of automatic cutting off negative pulse of the input signals, optional integrating time division spacing 0.2-1 ms, TTL starting trigger signal, automatic regularly work 20 s, and integrating 10 channel at the same time. (authors)

Introduction to the HL-LHC Project

CERN Document Server

Rossi , L

2015-01-01

The Large Hadron Collider (LHC) is one of largest scientific instruments ever built. It has been exploring the new energy frontier since 2010, gathering a global user community of 7,000 scientists. To extend its discovery potential, the LHC will need a major upgrade in the 2020s to increase its luminosity (rate of collisions) by a factor of five beyond its design value and the integrated luminosity by a factor of ten. As a highly complex and optimized machine, such an upgrade of the LHC must be carefully studied and requires about ten years to implement. The novel machine configuration, called High Luminosity LHC (HL-LHC), will rely on a number of key innovative technologies, representing exceptional technological challenges, such as cutting-edge 11–12 tesla superconducting magnets, very compact superconducting cavities for beam rotation with ultra-precise phase control, new technology for beam collimation and 300-meter-long high-power superconducting links with negligible energy dissipation. HL-LHC federa...

Analysis of Comparative Sequence and Genomic Data to Verify Phylogenetic Relationship and Explore a New Subfamily of Bacterial Lipases.

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Malihe Masomian

Full Text Available Thermostable and organic solvent-tolerant enzymes have significant potential in a wide range of synthetic reactions in industry due to their inherent stability at high temperatures and their ability to endure harsh organic solvents. In this study, a novel gene encoding a true lipase was isolated by construction of a genomic DNA library of thermophilic Aneurinibacillus thermoaerophilus strain HZ into Escherichia coli plasmid vector. Sequence analysis revealed that HZ lipase had 62% identity to putative lipase from Bacillus pseudomycoides. The closely characterized lipases to the HZ lipase gene are from thermostable Bacillus and Geobacillus lipases belonging to the subfamily I.5 with ≤ 57% identity. The amino acid sequence analysis of HZ lipase determined a conserved pentapeptide containing the active serine, GHSMG and a Ca(2+-binding motif, GCYGSD in the enzyme. Protein structure modeling showed that HZ lipase consisted of an α/β hydrolase fold and a lid domain. Protein sequence alignment, conserved regions analysis, clustal distance matrix and amino acid composition illustrated differences between HZ lipase and other thermostable lipases. Phylogenetic analysis revealed that this lipase represented a new subfamily of family I of bacterial true lipases, classified as family I.9. The HZ lipase was expressed under promoter Plac using IPTG and was characterized. The recombinant enzyme showed optimal activity at 65 °C and retained ≥ 97% activity after incubation at 50 °C for 1h. The HZ lipase was stable in various polar and non-polar organic solvents.

Fat digestion in the stomach: stability of lingual lipase in the gastric environment.

Science.gov (United States)

Fink, C S; Hamosh, P; Hamosh, M

1984-03-01

Digestion of dietary fat starts in the stomach, where lingual lipase hydrolyzes triglycerides to free fatty acids and partial glycerides at pH 3.0-6.0. Lingual lipase is secreted continuously from lingual serous glands and accumulates in the stomach between meals, when gastric pH is less than 3.0. We have, therefore, examined the resistance of lingual lipase to low pH and its possible protection by dietary components present in the stomach contents. Partially purified rat lingual lipase (7-15 micrograms enzyme protein) was preincubated at 37 degrees C for 10-60 min at pH 1.0-6.0 before incubation for assay of lipolytic activity, hydrolysis of tri-[3H]olein at pH 5.4. The data show that partially purified rat lingual lipase preparations are stable at 37 degrees C in the pH range of 2.5-6.0. Enzyme activity, however, is rapidly and irreversibly lost during preincubation at pH 1.0-2.4 for 10-30 min. Protein (gelatin 1% or albumin 1% or 2.5%) cannot prevent the inactivation of lingual lipase at low pH. The large molecular species (molecular weight greater than 500,000) of lingual lipase (thought to be an aggregate of enzyme with lipids) is slightly more resistant to inactivation than the 46,000 dalton preparation, suggesting that lipids might protect the enzyme from inactivation. Indeed, about 60% of the initial lipase activity is preserved during incubation at pH 2.0 in the presence of 50 mM lecithin or 10 mM triolein. The data indicate that triglycerides which are hydrolyzed by this enzyme as well as phospholipids that are not hydrolyzed can prevent the inactivation of the enzyme.(ABSTRACT TRUNCATED AT 250 WORDS)

LIPASES PRODUZIDAS POR LEVEDURAS: CATALISADORES PODEROSOS PARA APLICAÇÕES INDUSTRIAIS

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Luiza Lux Lock

2007-12-01

Full Text Available O termo “enzimas lipolíticas” refere-se a lípases e hidrolases éster carboxílico. A produção de lipase é ampla entre as leveduras, mas poucas são capazes de produzir lipases com características interessantes e em quantidades suficientes para serem industrialmente úteis. A literatura relativa a lipases produzidas por Candida rugosa, Yarrowia (Candida lipolytica, Candida antarctica e outras leveduras produtoras de lípases é revisada. O uso de lípases recombinantes é discutido, com ênfase na utilização de sistemas de expressão heteróloga e desenho de quimeras. Finalmente, as três abordagens que visam à melhora da produção de lipase ou a modificação da seletividade do substrato da enzima (engenharia do meio, do biocatalisador e da proteína são discutidos.

m-DOPA addition in MAPLE immobilization of lipase for biosensor applications

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Valeria Califano

2015-12-01

Full Text Available Matrix Assisted Pulsed Laser Evaporation (MAPLE is a thin film deposition technique which uses a pulsed laser beam impinging, inside a high vacuum chamber, on a frozen target containing the guest molecules in a volatile matrix to induce fast “evaporation” of the matrix, and ejection of the guest molecules. Lipase, an enzyme acting as a catalyst in hydrolysis of lipids, is widely used in biosensors for detection of triglycerides in blood serum. A key action to this purpose is lipase immobilization on a substrate. In a recent paper, we have shown that MAPLE technique is able to deposit lipase on a substrate in an active form. Here we show that addition to the guest/matrix target of a small amount of m-DOPA (3-(3,4-dihydroxyphenyl-2-methyl-l-alanine in order to improve adhesion and protect lipase secondary structure, also allows the lowering the laser pulse energy required for matrix evaporation and therefore the risk of damaging the enzyme.

Lipase-catalyzed ring-opening polymerization of lactones to polyesters and its mechanistic aspects.

Science.gov (United States)

Namekawa, S; Suda, S; Uyama, H; Kobayashi, S

1999-01-01

Lipase catalysis induced a ring-opening polymerization of lactones with different ring-sizes. Small-size (four-membered) and medium-size lactones (six- and seven-membered) as well as macrolides (12-, 13-, 16-, and 17-membered) were subjected to lipase-catalyzed polymerization. The polymerization behaviors depended primarily on the lipase origin and the monomer structure. The macrolides showing much lower anionic polymerizability were enzymatically polymerized faster than epsilon-caprolactone. The granular immobilized lipase derived from Candida antartica showed extremely efficient catalysis in the polymerization of epsilon-caprolactone. Single-step terminal functionalization of the polyester was achieved by initiator and terminator methods. The enzymatic polymerizability of lactones was quantitatively evaluated by Michaelis-Menten kinetics.

Evaluation of the catalytic activity of lipases immobilized on chrysotile for esterification

Energy Technology Data Exchange (ETDEWEB)

Silva, Jane E.S.; Jesus, Paulo C. [Universidade Regional de Blumenau, SC (Brazil). Dept. de Quimica]. E-mail: pcj@furb.rct-sc.br

2003-06-01

In the present work, the ester synthesis in organic media catalyzed by lipases immobilized on chrysotile was studied. Lipases of different sources (Mucor javanicus, Pseudomonas cepacia, Rhizopus oryzae, Aspergillus niger and Candida rugosa) were immobilized on chrysotile, an inexpensive magnesium silicate, and used for esterification of hexanoic, octanoic and lauric acid with methanol, ethanol, 1-butanol and 1-octanol at 25 deg C in hexane as solvent. The best results were obtained with Mucor javanicus lipase and lauric acid giving yields of 62-97% of ester. (author)

Evaluation of the catalytic activity of lipases immobilized on chrysotile for esterification

International Nuclear Information System (INIS)

Silva, Jane E.S.; Jesus, Paulo C.

2003-01-01

In the present work, the ester synthesis in organic media catalyzed by lipases immobilized on chrysotile was studied. Lipases of different sources (Mucor javanicus, Pseudomonas cepacia, Rhizopus oryzae, Aspergillus niger and Candida rugosa) were immobilized on chrysotile, an inexpensive magnesium silicate, and used for esterification of hexanoic, octanoic and lauric acid with methanol, ethanol, 1-butanol and 1-octanol at 25 deg C in hexane as solvent. The best results were obtained with Mucor javanicus lipase and lauric acid giving yields of 62-97% of ester. (author)

The CMS ECAL Upgrade for Precision Crystal Calorimetry at the HL-LHC

CERN Document Server

Petyt, David Anthony

2018-01-01

The electromagnetic calorimeter (ECAL) of the Compact Muon Solenoid Experiment (CMS) is operating at the Large Hadron Collider (LHC) in 2016 with proton-proton collisions at 13 TeV center-of-mass energy and at a bunch spacing of 25 ns. Challenging running conditions for CMS are expected after the High-Luminosity upgrade of the LHC (HL-LHC). We review the design and R and D studies for the CMS ECAL crystal calorimeter upgrade and present first test beam studies. Particular challenges at HL-LHC are the harsh radiation environment, the increasing data rates and the extreme level of pile-up events, with up to 200 simultaneous proton-proton collisions. We present test beam results of hadron irradiated PbWO$_{4}$ crystals up to fluences expected at the HL-LHC. We also report on the R and D for the new readout and trigger electronics, which must be upgraded due to the increased trigger and latency requirements at the HL-LHC.

HL-LHC and HE-LHC Upgrade Plans and Opportunities for US Participation

Science.gov (United States)

Apollinari, Giorgio

2017-01-01

The US HEP community has identified the exploitation of physics opportunities at the High Luminosity-LHC (HL-LHC) as the highest near-term priority. Thanks to multi-year R&D programs, US National Laboratories and Universities have taken the leadership in the development of technical solutions to increase the LHC luminosity, enabling the HL-LHC Project and uniquely positioning this country to make critical contributions to the LHC luminosity upgrade. This talk will describe the shaping of the US Program to contribute in the next decade to HL-LHC through newly developed technologies such as Nb3Sn focusing magnets or superconducting crab cavities. The experience gained through the execution of the HL-LHC Project in the US will constitute a pool of knowledge and capabilities allowing further developments in the future. Opportunities for US participations in proposed hadron colliders, such as a possible High Energy-LHC (HE-LHC), will be described as well.

Characterization of neutral lipase BT-1 isolated from the labial gland of Bombus terrestris males.

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Jana Brabcová

Full Text Available BACKGROUND: In addition to their general role in the hydrolysis of storage lipids, bumblebee lipases can participate in the biosynthesis of fatty acids that serve as precursors of pheromones used for sexual communication. RESULTS: We studied the temporal dynamics of lipolytic activity in crude extracts from the cephalic part of Bombus terrestris labial glands. Extracts from 3-day-old males displayed the highest lipolytic activity. The highest lipase gene expression level was observed in freshly emerged bumblebees, and both gene expression and lipase activity were lower in bumblebees older than 3 days. Lipase was purified from labial glands, further characterized and named as BT-1. The B. terrestris orthologue shares 88% sequence identity with B. impatiens lipase HA. The molecular weight of B. terrestris lipase BT-1 was approximately 30 kDa, the pH optimum was 8.3, and the temperature optimum was 50°C. Lipase BT-1 showed a notable preference for C8-C10 p-nitrophenyl esters, with the highest activity toward p-nitrophenyl caprylate (C8. The Michaelis constant (Km and maximum reaction rate (Vmax for p-nitrophenyl laurate hydrolysis were Km = 0.0011 mM and Vmax = 0.15 U/mg. CONCLUSION: This is the first report describing neutral lipase from the labial gland of B. terrestris. Our findings help increase understanding of its possible function in the labial gland.

Elevação da lipase e amilase no doente crítico: estudo retrospectivo Increased lipase and amilase levels in critically ill patients: retrospective study

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Margarida Ferreira

2008-12-01

Full Text Available OBJETIVOS: A elevação da lipase e amilase séricas são frequentemente encontradas em doentes internados em unidade de terapia intensiva sem que exista doença pancreática prévia, constituindo um desafio diagnóstico e terapêutico. Baseados nesta evidência os autores propuseram-se a determinar a incidência de hiperlipasemia assintomática nos doentes críticos, fatores desencadeantes e evolução clínica destes doentes. MÉTODOS: Estudo retrospectivo dos doentes internados na unidade de terapia intensiva de 1 de janeiro a 31 de dezembro de 2006, excluídas internações por pancreatite aguda, história de patologia pancreática, insuficiência renal ou falta de dados. Pacientes foram distribuídos em dois grupos (com e sem hiperlipasemia e feita comparação considerando diversas variáveis clínicas, laboratoriais, imagiológicas. Análise estatística: SPSS 13; testes t de Student e qui² (IC 95%, com significância estatística se p38 ºC (pOBJECTIVES: Elevated lipase and amylase are commonly found in patients in intensive care unit without a previously recognized pancreatic illness, constituting a diagnostic and therapeutic challenge. The authors therefore proposed to determine the frequency of asymptomatic high serum lipase in critically ill patients, involved risk factors and outcome. METHODS: Retrospective study of patients admitted in an intensive care unit from January 1 to December 31, 2006, excluding admissions for acute pancreatitis, history of pancreatic disease, renal insufficiency or lacking of data. Patients were divided in two groups (with and without high serum lipase that were compared for clinical, laboratory and radiological variables. Statistical analysis: SPSS 13; Student's t test and Chi-square test (CI 95% with statistical significance if p< 0.05. RESULTS: 102 patients were included with high serum lipase was present in 39.2% of patients, mean lipase of 797U/L. Patients with high serum lipase had longer hospital

Purification and characterization of a new cold active lipase, EnL A ...

African Journals Online (AJOL)

SONU

2015-06-03

Jun 3, 2015 ... palm oil mill effluent dump sites, Pedavegi, West Godavari Dist, A.P. India and was ... carried out with the lipase production medium optimized using ..... Non edible Castor Oil by Immobilized Lipase from Bacillus aerius.

Enzymatic activity of a novel halotolerant lipase from Haloarcula hispanica 2TK2

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Ozgen Melis

2016-06-01

Full Text Available A strain of Haloarcula hispanica isolated from Tuzkoy salt mine, Turkey exhibited extracellular lipolytic activity. Important parameters such as carbon sources and salt concentration for lipase production were investigated. Optimal conditions for the enzyme production from Haloarcula hispanica 2TK2 were determined. It was observed that the lipolytic activity of Haloarcula hispanica was stimulated by some of the carbon sources. The high lipase acitivity values were obtained in the presence of 2% (v/v walnut oil (6.16 U/ml, 1% (v/v fish oil (5.07 U/ml, 1% (v/v olive oil (4.52 U/ml and 1% (w/v stearic acid (4.88 U/ml at 4M NaCl concentration. Lipase was partially purified by ammonium sulfate precipitation and ultrafiltration. Optimal temperature and pH values were determined as 45°C and 8.0, respectively. Lipase activity decreased with the increasing salt concentration, but 85% activity of the enzyme was maintained at 5M NaCl concentration. The enzyme preserved 41% of its relative activity at 90°C. The partially purified lipase maintained its activity in the presence of surfactants such as Triton X-100 and SDS. Therefore, the lipase which is an extremozyme may have potential applications especially in detergent industry.

Pancreatic lipase inhibitory constituents from Morus alba leaves and optimization for extraction conditions.

Science.gov (United States)

Jeong, Ji Yeon; Jo, Yang Hee; Kim, Seon Beom; Liu, Qing; Lee, Jin Woo; Mo, Eun Jin; Lee, Ki Yong; Hwang, Bang Yeon; Lee, Mi Kyeong

2015-06-01

The leaves of Morus alba (Moraceae) have been traditionally used for the treatment of metabolic diseases including diabetes and hyperlipidemia. Thus, inhibitory effect of M. alba leaves on pancreatic lipase and their active constituents were investigated in this study. Twenty phenolic compounds including ten flavonoids, eight benzofurans, one stilbene and one chalcones were isolated from the leaves of M. alba. Among the isolated compounds, morachalcone A (20) exerted strong pancreatic lipase inhibition with IC50 value of 6.2 μM. Other phenolic compounds containing a prenyl group showed moderate pancreatic lipase inhibition with IC50 value of <50 μM. Next, extraction conditions with maximum pancreatic lipase inhibition and phenolic content were optimized using response surface methodology with three-level-three-factor Box-Behnken design. Our results suggested the optimized extraction condition for maximum pancreatic lipase inhibition and phenolic content as ethanol concentration of 74.9%; temperature 57.4 °C and sample/solvent ratio, 1/10. The pancreatic lipase inhibition and total phenolic content under optimized condition were found to be 58.5% and 26.2 μg GAE (gallic acid equivalent)/mg extract, respectively, which were well matched with the predicted value. Copyright © 2015 Elsevier Ltd. All rights reserved.

The effect of interaction between Lipoprotein Lipase and ApoVLDL-II ...

African Journals Online (AJOL)

Body weight, abdominal fat weight and serum biochemical levels were determined from lean and fat chicken breeds at 12 weeks of age. Single nucleotide polymorphism (SNP) in apoVLDL-II and lipoprotein lipase genes was screened by PCR-SSCP and detected by direct sequencing. Lipoprotein lipase gene frequency ...

Significantly Elevated Serum Lipase in Pregnancy with Nausea and Vomiting: Acute Pancreatitis or Hyperemesis Gravidarum?

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Amanda Johnson

2015-01-01

Full Text Available Hyperemesis gravidarum is a severe manifestation of nausea and vomiting of pregnancy and it is associated with weight loss and metabolic abnormalities. It is known that abnormal laboratory values, including mildly elevated serum lipase level, could be associated with hyperemesis gravidarum. However, in this case report details of two women with hyperemesis gravidarum but with significantly elevated serum lipase levels were discussed. These patients presented with severe nausea and vomiting but without abdominal pain. They were found to have severely elevated lipase levels over 1,000 units/liter. In the absence of other findings of pancreatitis, they were treated with conservative measures for hyperemesis gravidarum, with eventual resolution to normal lipase levels. Although significantly elevated lipase level in pregnant patients with nausea and vomiting is a concern for acute pancreatitis, these two cases of significantly elevated serum lipase without other clinical findings of pancreatitis led to this report that serum lipase could be quite elevated in hyperemesis gravidarum and that it might not be an accurate biochemical marker for acute pancreatitis. Imaging studies are thus necessary to establish the diagnosis of acute pancreatitis.

Controlled lid-opening in Thermomyces lanuginosus lipase- An engineered switch for studying lipase function

DEFF Research Database (Denmark)

Skjold-Jørgensen, Jakob; Vind, Jesper; Moroz, Olga V.

2017-01-01

Here, we present a lipase mutant containing a biochemical switch allowing a controlled opening and closing of the lid independent of the environment. The closed form of the TlL mutant shows low binding to hydrophobic surfaces compared to the binding observed after activating the controlled switch...... inducing lid-opening. We directly show that lipid binding of this mutant is connected to an open lid conformation demonstrating the impact of the exposed amino acid residues and their participation in binding at the water-lipid interface. The switch was created by introducing two cysteine residues......-D measurements revealed a seven-fold increase in binding rate for the unlocked lipase. The TlL_locked mutant shows structural changes across the protein important for understanding the mechanism of lid-opening and closing. Our experimental results reveal sites of interest for future mutagenesis studies aimed...

Relevant pH and lipase for in vitro models of gastric digestion.

Science.gov (United States)

Sams, Laura; Paume, Julie; Giallo, Jacqueline; Carrière, Frédéric

2016-01-01

The development of in vitro digestion models relies on the availability of in vivo data such as digestive enzyme levels and pH values recorded in the course of meal digestion. The variations of these parameters along the GI tract are important for designing dynamic digestion models but also static models for which the choice of representative conditions of the gastric and intestinal conditions is critical. Simulating gastric digestion with a static model and a single set of parameters is particularly challenging because the variations in pH and enzyme concentration occurring in the stomach are much broader than those occurring in the small intestine. A review of the literature on this topic reveals that most models of gastric digestion use very low pH values that are not representative of the fed conditions. This is illustrated here by showing the variations in gastric pH as a function of meal gastric emptying instead of time. This representation highlights those pH values that are the most relevant for testing meal digestion in the stomach. Gastric lipolysis is still largely ignored or is performed with microbial lipases. In vivo data on gastric lipase and lipolysis have however been collected in humans and dogs during test meals. The biochemical characterization of gastric lipase has shown that this enzyme is rather unique among lipases: (i) stability and activity in the pH range 2 to 7 with an optimum at pH 4-5.4; (ii) high tensioactivity that allows resistance to bile salts and penetration into phospholipid layers covering TAG droplets; (iii) sn-3 stereospecificity for TAG hydrolysis; and (iv) resistance to pepsin. Most of these properties have been known for more than two decades and should provide a rational basis for the replacement of gastric lipase by other lipases when gastric lipase is not available.

The genotypic diversity and lipase production of some thermophilic bacilli from different genera

OpenAIRE

Koc, Melih; Cokmus, Cumhur; Cihan, Arzu Coleri

2015-01-01

Abstract Thermophilic 32 isolates and 20 reference bacilli were subjected to Rep-PCR and ITS-PCR fingerprinting for determination of their genotypic diversity, before screening lipase activities. By these methods, all the isolates and references could easily be differentiated up to subspecies level from each other. In screening assay, 11 isolates and 7 references were found to be lipase producing. Their extracellular lipase activities were measured quantitatively by incubating in both tributy...

Effects of methanol on lipases: molecular, kinetic and process issues in the production of biodiesel.

Science.gov (United States)

Lotti, Marina; Pleiss, Jürgen; Valero, Francisco; Ferrer, Pau

2015-01-01

The biotechnological production of biodiesel is based on transesterification/esterification reactions between a source of fatty acids and a short-chain alcohol, usually methanol, catalysed by enzymes belonging to the class known as lipases. Several lipases used in industrial processes, although stable in the presence of other organic solvents, are inactivated by methanol at or below the concentration optimal for biodiesel production, making it necessary to use stepwise methanol feeding or pre-treatment of the enzyme. In this review article we focus on what is currently know about methanol inactivation of lipases, a phenomenon which is not common to all lipase enzymes, with the goal of improving the biocatalytic process. We suggest that different mechanisms can lead to inactivation of different lipases, in particular substrate inhibition and protein unfolding. Attempts to improve the performances of methanol sensitive lipases by mutagenesis as well as process engineering approaches are also summarized. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Preparation of Biodiesel with Liquid Synergetic Lipases from Rapeseed Oil Deodorizer Distillate.

Science.gov (United States)

Zeng, Leping; He, Yaojia; Jiao, Liangcheng; Li, Kai; Yan, Yunjun

2017-11-01

To reduce industrial production cost, cheap and easily available rapeseed oil deodorizer distillates were used as feedstock to prepare biodiesel in this study. As a result, liquid forms of Candida rugosa lipase and Rhizopus oryzae lipase (ROL) were functioned as new and effective catalysts with biodiesel yield of 92.63% for 30 h and 94.36% for 9 h, respectively. Furthermore, the synergetic effect between the two lipases was employed to enhance biodiesel yield with a result of 98.16% in 6 h under optimized conditions via response surface methodology. The obtained conversion rate surpassed both yields of the individual two lipases and markedly shortened the reaction time. The resultant optimal conditions were ROL ratio 0.84, water content 46 wt% (w/w), reaction temperature 34 °C, and reaction time 6 h.

Production of extracellular lipase by the phytopathogenic fungus Fusarium solani FS1

OpenAIRE

Maia, Maria de Mascena Diniz; Morais, Marcia Maria Camargo de; Morais Jr., Marcos Antonio de; Melo, Eduardo Henrique Magalhães; Lima Filho, José Luiz de

1999-01-01

A Brazilian strain of Fusarium solani was tested for extracellular lipase production in peptone-olive oil medium. The fungus produced 10,500 U.l-1 of lipase after 72 hours of cultivation at 25oC in shake-flask at 120 rpm in a medium containing 3% (w/v) peptone plus 0.5% (v/v) olive oil. Glucose (1% w/v) was found to inhibit the inductive effect of olive oil. Peptone concentrations below 3% (w/v) resulted in a reduced lipase production while increased olive oil concentration (above 0.5%) did n...

Evaluation of the catalytic activity of lipases immobilized on chrysotile for esterification

Directory of Open Access Journals (Sweden)

Silva Jane E. S.

2003-01-01

Full Text Available In the present work, the ester synthesis in organic media catalyzed by lipases immobilized on chrysotile was studied. Lipases of different sources (Mucor javanicus, Pseudomonas cepacia, Rhizopus oryzae, Aspergillus niger and Candida rugosa were immobilized on chrysotile, an inexpensive magnesium silicate, and used for esterification of hexanoic, octanoic and lauric acid with methanol, ethanol, 1-butanol and 1-octanol at 25ºC in hexane as solvent. The best results were obtained with Mucor javanicus lipase and lauric acid giving yields of 62-97% of ester.

Modeling of lipase catalyzed ring-opening polymerization of epsilon-caprolactone.

Science.gov (United States)

Sivalingam, G; Madras, Giridhar

2004-01-01

Enzymatic ring-opening polymerization of epsilon-caprolactone by various lipases was investigated in toluene at various temperatures. The determination of molecular weight and structural identification was carried out with gel permeation chromatography and proton NMR, respectively. Among the various lipases employed, an immobilized lipase from Candida antartica B (Novozym 435) showed the highest catalytic activity. The polymerization of epsilon-caprolactone by Novozym 435 showed an optimal temperature of 65 degrees C and an optimum toluene content of 50/50 v/v of toluene and epsilon-caprolactone. As lipases can degrade polyesters, a maximum in the molecular weight with time was obtained due to the competition of ring opening polymerization and degradation by specific chain end scission. The optimum temperature, toluene content, and the variation of molecular weight with time are consistent with earlier observations. A comprehensive model based on continuous distribution kinetics was developed to model these phenomena. The model accounts for simultaneous polymerization, degradation and enzyme deactivation and provides a technique to determine the rate coefficients for these processes. The dependence of these rate coefficients with temperature and monomer concentration is also discussed.

Different Covalent Immobilizations Modulate Lipase Activities of Hypocrea pseudokoningii

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Marita G. Pereira

2017-09-01

Full Text Available Enzyme immobilization can promote several advantages for their industrial application. In this work, a lipase from Hypocrea pseudokoningii was efficiently linked to four chemical supports: agarose activated with cyanogen bromide (CNBr, glyoxyl-agarose (GX, MANAE-agarose activated with glutaraldehyde (GA and GA-crosslinked with glutaraldehyde. Results showed a more stable lipase with both the GA-crosslinked and GA derivatives, compared to the control (CNBr, at 50 °C, 60 °C and 70 °C. Moreover, all derivatives were stabilized when incubated with organic solvents at 50%, such as ethanol, methanol, n-propanol and cyclohexane. Furthermore, lipase was highly activated (4-fold in the presence of cyclohexane. GA-crosslinked and GA derivatives were more stable than the CNBr one in the presence of organic solvents. All derivatives were able to hydrolyze sardine, açaí (Euterpe oleracea, cotton seed and grape seed oils. However, during the hydrolysis of sardine oil, GX derivative showed to be 2.3-fold more selectivity (eicosapentaenoic acid (EPA/docosahexaenoic acid (DHA ratio than the control. Additionally, the types of immobilization interfered with the lipase enantiomeric preference. Unlike the control, the other three derivatives preferably hydrolyzed the R-isomer of 2-hydroxy-4-phenylbutanoic acid ethyl ester and the S-isomer of 1-phenylethanol acetate racemic mixtures. On the other hand, GX and CNBr derivatives preferably hydrolyzed the S-isomer of butyryl-2-phenylacetic acid racemic mixture while the GA and GA-crosslink derivatives preferably hydrolyzed the R-isomer. However, all derivatives, including the control, preferably hydrolyzed the methyl mandelate S-isomer. Moreover, the derivatives could be used for eight consecutive cycles retaining more than 50% of their residual activity. This work shows the importance of immobilization as a tool to increase the lipase stability to temperature and organic solvents, thus enabling the possibility of

GDSL lipases modulate immunity through lipid homeostasis in rice.

Science.gov (United States)

Gao, Mingjun; Yin, Xin; Yang, Weibing; Lam, Sin Man; Tong, Xiaohong; Liu, Jiyun; Wang, Xin; Li, Qun; Shui, Guanghou; He, Zuhua

2017-11-01

Lipids and lipid metabolites play important roles in plant-microbe interactions. Despite the extensive studies of lipases in lipid homeostasis and seed oil biosynthesis, the involvement of lipases in plant immunity remains largely unknown. In particular, GDSL esterases/lipases, characterized by the conserved GDSL motif, are a subfamily of lipolytic enzymes with broad substrate specificity. Here, we functionally identified two GDSL lipases, OsGLIP1 and OsGLIP2, in rice immune responses. Expression of OsGLIP1 and OsGLIP2 was suppressed by pathogen infection and salicylic acid (SA) treatment. OsGLIP1 was mainly expressed in leaf and leaf sheath, while OsGLIP2 showed high expression in elongating internodes. Biochemical assay demonstrated that OsGLIP1 and OsGLIP2 are functional lipases that could hydrolyze lipid substrates. Simultaneous down-regulation of OsGLIP1 and OsGLIP2 increased plant resistance to both bacterial and fungal pathogens, whereas disease resistance in OsGLIP1 and OsGLIP2 overexpression plants was significantly compromised, suggesting that both genes act as negative regulators of disease resistance. OsGLIP1 and OsGLIP2 proteins mainly localize to lipid droplets and the endoplasmic reticulum (ER) membrane. The proper cellular localization of OsGLIP proteins is indispensable for their functions in immunity. Comprehensive lipid profiling analysis indicated that the alteration of OsGLIP gene expression was associated with substantial changes of the levels of lipid species including monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG). We show that MGDG and DGDG feeding could attenuate disease resistance. Taken together, our study indicates that OsGLIP1 and OsGLIP2 negatively regulate rice defense by modulating lipid metabolism, thus providing new insights into the function of lipids in plant immunity.

Will ALICE run in the HL-LHC era?

International Nuclear Information System (INIS)

Wessels, J.P.

2012-01-01

We will present the perspectives for ion running in the HL-LHC era. In particular, ALICE is preparing a significant upgrade of its rate capabilities and is further extending its particle identification potential. This paves the way for heavy ion physics at unprecedented luminosities, which are expected in the HL-LHC era with the heaviest ions. Here, we outline a scenario, in which ALICE will be taking data at a luminosity of L > 6*10 27 cm -2 *s -1 for Pb-Pb with the aim of collecting at least 10 nb -1 . The potential interest of data-taking during high luminosity proton runs for ATLAS and CMS will also be commented. (author)

Hepatic lipidosis in anorectic, lactating holstein cattle: a retrospective study of serum biochemical abnormalities.

Science.gov (United States)

Cebra, C K; Garry, F B; Getzy, D M; Fettman, M J

1997-01-01

The association between hepatic lipidosis (HL) and disease in 59 anorectic, ketotic, lactating Holstein heifers and cows was investigated. Severe HL, as determined by histologic evaluation of liver tissue, was present in 46 animals; only half of these animals required intensive treatment for ketosis, and only half had serum biochemical evidence of liver disease, as determined by the presence of a last value of 2-fold or greater than the upper limit of the reference ranges for at least 2 of the 4 serum tests: gamma-glutamyl transferase, aspartate aminotransferase, and sorbitol dehydrogenase activities and bile acid concentrations. Most cattle with biochemical evidence of liver disease and severe HL had been lactating for 14 or more days. Cows that required intensive treatment inconsistently had serum biochemical evidence of liver disease. Although cattle with severe HL had significantly higher serum bilirubin concentrations and aspartate aminotransferase and sorbitol dehydrogenase activities than cattle with less severe lipidosis, the specificity of abnormally high serum sorbitol dehydrogenase activity or bilirubin concentration for severe lipidosis was only 8%. Abnormally high serum aspartate aminotransferase activity was 83% sensitive and 62% specific for severe lipidosis. Serum glucose and total carbon dioxide concentrations were significantly lower in cattle with severe lipidosis than in those with mild or moderate lipidosis, and low serum glucose or total carbon dioxide concentrations were rare in cattle without severe lipidosis. From these data, we conclude that the use of a single biochemical or histopathologic criterion to define severity of disease or degree of liver compromise in anorectic, ketotic cows results in the misidentification of many animals.

Liquid lipases for enzymatic concentration of n-3 polyunsaturated fatty acids in monoacylglycerols via ethanolysis: Catalytic specificity and parameterization.

Science.gov (United States)

He, Yongjin; Li, Jingbo; Kodali, Sitharam; Balle, Thomas; Chen, Bilian; Guo, Zheng

2017-01-01

This work examined catalytic specificity and fatty acid selectivity of five liquid lipases C. antarctica lipase A and B (CAL-A/B), and lipase TL (T. lanuginosus), Eversa Transfrom and NS in ethanolysis of fish oil with the aim to concentrate n-3 PUFAs into monoacylglycerols (MAGs) products. Lipase TL, Eversa Transform & NS entail a much faster reaction and produce higher MAGs yield (>30%); whereas CAL-A obtains the highest concentration of n-3 PUFAs/DHA/EPA into MAGs products (88.30%); followed by lipase NS (81.02%). 13 C NMR analysis indicates that CAL-B and lipase TL are sn-1,3 specific; but CAL-A and lipase Eversa Transform are non-regiospecific or weak sn-2 specific; which plausibly explains high enrichment effect of the latter two lipases. All liquid lipases are observed reusable for a certain times (lipase Eversa Transform up to 12 times), demonstrating their competitive advantage over immobilized form for industrial application because of their higher activity and cheaper operation cost. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of Morinda citrifolia (Noni-Enriched Diet on Hepatic Heat Shock Protein and Lipid Metabolism-Related Genes in Heat Stressed Broiler Chickens

Directory of Open Access Journals (Sweden)

Joshua Flees

2017-11-01

Full Text Available Heat stress (HS has been reported to alter fat deposition in broilers, however the underlying molecular mechanisms are not well-defined. The objectives of the current study were, therefore: (1 to determine the effects of acute (2 h and chronic (3 weeks HS on the expression of key molecular signatures involved in hepatic lipogenic and lipolytic programs, and (2 to assess if diet supplementation with dried Noni medicinal plant (0.2% of the diet modulates these effects. Broilers (480 males, 1 d were randomly assigned to 12 environmental chambers, subjected to two environmental conditions (heat stress, HS, 35°C vs. thermoneutral condition, TN, 24°C and fed two diets (control vs. Noni in a 2 × 2 factorial design. Feed intake and body weights were recorded, and blood and liver samples were collected at 2 h and 3 weeks post-heat exposure. HS depressed feed intake, reduced body weight, and up regulated the hepatic expression of heat shock protein HSP60, HSP70, HSP90 as well as key lipogenic proteins (fatty acid synthase, FASN; acetyl co-A carboxylase alpha, ACCα and ATP citrate lyase, ACLY. HS down regulated the hepatic expression of lipoprotein lipase (LPL and hepatic triacylglycerol lipase (LIPC, but up-regulated ATGL. Although it did not affect growth performance, Noni supplementation regulated the hepatic expression of lipogenic proteins in a time- and gene-specific manner. Prior to HS, Noni increased ACLY and FASN in the acute and chronic experimental conditions, respectively. During acute HS, Noni increased ACCα, but reduced FASN and ACLY expression. Under chronic HS, Noni up regulated ACCα and FASN but it down regulated ACLY. In vitro studies, using chicken hepatocyte cell lines, showed that HS down-regulated the expression of ACCα, FASN, and ACLY. Treatment with quercetin, one bioactive ingredient in Noni, up-regulated the expression of ACCα, FASN, and ACLY under TN conditions, but it appeared to down-regulate ACCα and increase ACLY

Effect of Morinda citrifolia (Noni)-Enriched Diet on Hepatic Heat Shock Protein and Lipid Metabolism-Related Genes in Heat Stressed Broiler Chickens.

Science.gov (United States)

Flees, Joshua; Rajaei-Sharifabadi, Hossein; Greene, Elizabeth; Beer, Lesleigh; Hargis, Billy M; Ellestad, Laura; Porter, Tom; Donoghue, Annie; Bottje, Walter G; Dridi, Sami

2017-01-01

Heat stress (HS) has been reported to alter fat deposition in broilers, however the underlying molecular mechanisms are not well-defined. The objectives of the current study were, therefore: (1) to determine the effects of acute (2 h) and chronic (3 weeks) HS on the expression of key molecular signatures involved in hepatic lipogenic and lipolytic programs, and (2) to assess if diet supplementation with dried Noni medicinal plant (0.2% of the diet) modulates these effects. Broilers (480 males, 1 d) were randomly assigned to 12 environmental chambers, subjected to two environmental conditions (heat stress, HS, 35°C vs. thermoneutral condition, TN, 24°C) and fed two diets (control vs. Noni) in a 2 × 2 factorial design. Feed intake and body weights were recorded, and blood and liver samples were collected at 2 h and 3 weeks post-heat exposure. HS depressed feed intake, reduced body weight, and up regulated the hepatic expression of heat shock protein HSP60, HSP70, HSP90 as well as key lipogenic proteins (fatty acid synthase, FASN; acetyl co-A carboxylase alpha, ACCα and ATP citrate lyase, ACLY). HS down regulated the hepatic expression of lipoprotein lipase (LPL) and hepatic triacylglycerol lipase (LIPC), but up-regulated ATGL. Although it did not affect growth performance, Noni supplementation regulated the hepatic expression of lipogenic proteins in a time- and gene-specific manner. Prior to HS, Noni increased ACLY and FASN in the acute and chronic experimental conditions, respectively. During acute HS, Noni increased ACCα, but reduced FASN and ACLY expression. Under chronic HS, Noni up regulated ACCα and FASN but it down regulated ACLY. In vitro studies, using chicken hepatocyte cell lines, showed that HS down-regulated the expression of ACCα, FASN, and ACLY. Treatment with quercetin, one bioactive ingredient in Noni, up-regulated the expression of ACCα, FASN, and ACLY under TN conditions, but it appeared to down-regulate ACCα and increase ACLY levels

Microbial lipase mediated by health beneficial modification of cholesterol and flavors in food products: A review.

Science.gov (United States)

Sharma, Ranjana; Sharma, Nivedita

2017-06-14

The tremendous need of lipase in varied applications in biotechnological increases its economical value in food and allied industries. Lipase has an impressive number of applications viz. enhancements of flavor in food products (Cheese, butter, alcoholic beverages, milk chocolate and diet control food stuffs), detergent industry in removing oil, grease stain, organic chemical processing, textile industry, oleochemical industry, cosmetic industry and also as therapeutic agents in pharmaceutical industries. This communication extends the frontier of lipase catalyzed benefits to human body by lowering serum cholesterol and enhancement of flavor in different food products. Among all, multiple innovations going on in the field of lipase applications are widening its scope in food industries consistently. Therefore in the present work an effort has been made to explore the utilization of lipase in the field of food product enhancement. Supplementation of food products with lipase results in modification of its physical, chemical and biochemical properties by enhancing its therapeutic activity. Lipases are the most important enzymes used in food industries. They are utilized as industrial catalysts for lipid hydrolysis. Because of lipases hydrolysis nature it is widely exploited to catalyze lipids or fats in different food products and enhancement of food flavors. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

PPARγ regulates exocrine pancreas lipase.

Science.gov (United States)

Danino, Hila; Naor, Ronny Peri-; Fogel, Chen; Ben-Harosh, Yael; Kadir, Rotem; Salem, Hagit; Birk, Ruth

2016-12-01

Pancreatic lipase (triacylglycerol lipase EC 3.1.1.3) is an essential enzyme in hydrolysis of dietary fat. Dietary fat, especially polyunsaturated fatty acids (PUFA), regulate pancreatic lipase (PNLIP); however, the molecular mechanism underlying this regulation is mostly unknown. As PUFA are known to regulate expression of proliferator-activated receptor gamma (PPARγ), and as we identified in-silico putative PPARγ binding sites within the putative PNLIP promoter sequence, we hypothesized that PUFA regulation of PNLIP might be mediated by PPARγ. We used in silico bioinformatics tools, reporter luciferase assay, PPARγ agonists and antagonists, PPARγ overexpression in exocrine pancreas AR42J and primary cells to study PPARγ regulation of PNLIP. Using in silico bioinformatics tools we mapped PPARγ binding sites (PPRE) to the putative promoter region of PNLIP. Reporter luciferase assay in AR42J rat exocrine pancreas acinar cells transfected with various constructs of the putative PNLIP promoter showed that PNLIP transcription is significantly enhanced by PPARγ dose-dependently, reaching maximal levels with multi PPRE sites. This effect was significantly augmented in the presence of PPARγ agonists and reduced by PPARγ antagonists or mutagenesis abrogating PPRE sites. Over-expression of PPARγ significantly elevated PNLIP transcript and protein levels in AR42J cells and in primary pancreas cells. Moreover, PNLIP expression was up-regulated by PPARγ agonists (pioglitazone and 15dPGJ2) and significantly down-regulated by PPARγ antagonists in non-transfected rat exocrine pancreas AR42J cell line cells. PPARγ transcriptionally regulates PNLIP gene expression. This transcript regulation resolves part of the missing link between dietary PUFA direct regulation of PNLIP. Copyright © 2016 Elsevier B.V. All rights reserved.

Novel Lipases: Expression and Improvement for Applied Biocatalysis = Nuevas lipasas: expresión y mejoras para biocatálisis aplicadatalysi Novel Lipases: Expression and Improvement for Applied Biocatalysis = Nuevas lipasas: expresión y mejoras para biocatálisis aplicada

OpenAIRE

Infanzón Ramos, Belén

2017-01-01

[eng] This thesis is focused in the identification and improvement of lipases for biotechnological application. The importance of lipases is increasing in several industries. However, the commercial use of lipases is still a drawback in the economics of the lipase-based industrial applications. There are many tools for improving and adapting the enzyme properties to the desired requirements of a process that could lead lipase catalysis through a cost-effective process. In this context, the m...

Influence of dietary recombinant microbial lipase on performance and quality characteristics of rainbow trout, Oncorhynchus mykiss

DEFF Research Database (Denmark)

Samuelsen, Troels; Isaksen, Mai; McLean, Ewen

2001-01-01

In order to assess whether supplementary lipase affected growth and body composition of trout, four diets were produced, consisting of (A) feed containing high (2083 mg kg(-1)), (B) low (208.3 mg kg(-1)) concentrations of lipase, (C) heat-treated (inactivated) lipase (2083 mg kg(-1)), and (D......) a basal control diet. Rainbow trout (n = 40/tank; initial wt. 23.22 +/- 4.81 g; length 124.7 +/- 6.35 mm) were fed, according to commercial feed tables, 6 days/week for 202 days. Retained activity of supplemental lipase was verified by monitoring free fatty acid appearance (FAA), which was significantly...... higher(P Lipase addition had no effect(P > 0.05) on growth, fillet proximate composition, hepatosomatic, cardiac, or gut indices, and carcass percentage. However, lipase supplementation influenced the mono-unsaturated fatty acid profiles of the fillet (P

Effect of immobilized lipase supplementation of diets on the performance of the Japanese quails

International Nuclear Information System (INIS)

Abu-Taleb, A.M.; Ezzat, I.E.; Saleh, M.

2004-01-01

In the present study, lipase was immobilized onto two different supports, agarose and gelatin. Some physico-chemical properties of the free and immobilized lipase such as optimum temperature, optimum ph and storage stability were studied. Storage of the enzymes for 2 months showed that the free enzyme lost its activity, while the immobilized on the gelatin showed better resistance towards ph and temperature variations than that immobilized onto agarose. Four experiments were conducted to test the effect of the immobilized lipase supplementation on the productive performance of the Japanese quails. During the first 3 weeks, the addition of lipase to poultry diets caused an increase in the body weight gain of birds than the enzyme-free diet. An obvious improvement in quail day egg production during the laying period was observed with the groups fed on a diet supplemented with 3000 and 2000 I U of immobilized lipase per kilogram feed. Blood cholesterol was not affected with lipase addition, while total lipids were significantly increased. Significant reduction was also observed in thyroid hormones (T 3 and T 4 ) as compared with the control group

Quantitative approach to track lipase producing Pseudomonas sp. S1 in nonsterilized solid state fermentation.

Science.gov (United States)

Sahoo, R K; Subudhi, E; Kumar, M

2014-06-01

Proliferation of the inoculated Pseudomonas sp. S1 is quantitatively evaluated using ERIC-PCR during the production of lipase in nonsterile solid state fermentation an approach to reduce the cost of enzyme production. Under nonsterile solid state fermentation with olive oil cake, Pseudomonas sp. S1 produced 57·9 IU g(-1) of lipase. DNA fingerprints of unknown bacterial isolates obtained on Bushnell Haas agar (BHA) + tributyrin exactly matched with that of Pseudomonas sp. S1. Using PCR-based enumeration, population of Pseudomonas sp. S1 was proliferated from 7·6 × 10(4) CFU g(-1) after 24 h to 4·6 × 10(8) CFU g(-1) after 96 h, which tallied with the maximum lipase activity as compared to control. Under submerged fermentation (SmF), Pseudomonas sp. S1 produced maximum lipase (49 IU ml(-1) ) using olive oil as substrate, while lipase production was 9·754 IU ml(-1) when Pseudomonas sp. S1 was grown on tributyrin. Optimum pH and temperature of the crude lipase was 7·0 and 50°C. Crude enzyme activity was 71·2% stable at 50°C for 360 min. Pseudomonas sp. S1 lipase was also stable in methanol showing 91·6% activity in the presence of 15% methanol, whereas 75·5 and 51·1% of activity were retained in the presence of 20 and 30% methanol, respectively. Thus, lipase produced by Pseudomonas sp. S1 is suitable for the production of biodiesel as well as treatment of oily waste water. This study presents the first report on the production of thermophilic organic solvent tolerant lipase using agro-industry waste in nonsterile solid state fermentation. Positive correlation between survival of Pseudomonas sp. S1 and lipase production under nonsterile solid state fermentation was established, which may emphasize the need to combine molecular tools and solid state fermentation in future studies. Our study brings new insights into the lipase production in cost-effective manner, which is an industrially relevant approach. © 2014 The Society for Applied Microbiology.

A discussion on practicable scheme for machine control system of HL-2A tokamak

International Nuclear Information System (INIS)

Li Qiang; Song Xianming; Jiang Chao

2001-01-01

This is the modified version of The Preliminary Design on the Hardware and Nets of HL-2A Tokamak. In this version, centralized control as well as the field bus communication on HL-2A Tokamak is used. The hardware components and the operational theory are introduced. The questions of practice program, extensibility, centralized control, cooperation with other subsystems and the continuous adaptation of present device are all discussed. The budget of the system is detailed. To keep the step with the overall engineering constructions of HL-2A, suggestions of the time program are presented for the system design, instrument purchases, installation, construction, user program development and the final operation processes for the machine control system of HL-2A Tokamak

Sequential Detection of Thermophilic Lipase and Protease by Zymography.

Science.gov (United States)

Kurz, Liliana; Hernández, Zully; Contreras, Lellys M; Wilkesman, Jeff

2017-01-01

Lipase and protease present in cell-free fractions of thermophilic Bacillus sp. cultures were analyzed by polyacrylamide gel (PAG) electrophoresis. After run, the gel is electrotransferred to another PAG copolymerized with glycerol tributyrate, olive oil, and gelatin. This multi-substrate gel was incubated first for lipase detection, until bands appeared, and then stained with Coomassie for protease detection. Advantages of this sequential procedure are the detection of two different enzyme activities on a single PAG, beside time and resource saving.

Lipases: particularly effective biocatalysts for cosmetic active ingredients

Directory of Open Access Journals (Sweden)

Yvergnaux Florent

2017-07-01

Full Text Available Enzymes are the tools of choice in the on-going quest for non-pollutant processes to discover molecules for use in skin products. Amongst these biocatalysts, lipases offer considerable potential in terms of ingredient development and are of interest in skin dermocosmetic formulations possessing sensory or biological activities. Lipases have been studied for around thirty years and, in most cases, these enzymes function under what are deemed to be mild conditions, displaying remarkable efficacy particularly in terms of selectivity. This particularly effective strategy will be illustrated through typical synthesis, demonstrating how ester or amide active ingredients are obtained.

Improvement in biodiesel production from soapstock oil by one-stage lipase catalyzed methanolysis

International Nuclear Information System (INIS)

Su, Erzheng; Wei, Dongzhi

2014-01-01

Highlights: • Soapstock is a less expensive feedstock reservoir for biodiesel production. • Addition of tert-alcohol can enhance the yield of fatty acid methyl ester significantly. • One-stage lipase catalyzed methanolysis of soapstock oil was successfully developed. • FAME yield of 95.2% was obtained with low lipase loading in a shorter reaction time. - Abstract: A major obstacle in the commercialization of biodiesel is its cost of manufacturing, primarily the raw material cost. In order to decrease the cost of biodiesel, soapstock oil was investigated as the feedstock for biodiesel production. Because the soapstock oil containing large amounts of free fatty acids (FFAs) cannot be effectively converted to biodiesel, complicated two-stage process (esterification followed by transesterification) was generally adopted. In this study, simple one-stage lipase catalyzed methanolysis of soapstock oil was developed via one-pot esterification and transesterification. Water produced by lipase catalyzed esterification of FFAs affected the lipase catalyzed transesterification of glycerides in the soapstock oil severely. Addition of tert-alcohol could overcome this problem and enhance the fatty acid methyl ester (FAME) yield from 42.8% to 76.4%. The FAME yield was further elevated to 95.2% by optimizing the methanol/oil molar ratio, lipase amount, and water absorbent. The developed process enables the simple, efficient, and green production of biodiesel from soapstock oil, providing with a potential industrial application

Recombinant Lipases and Phospholipases and Their Use as Biocatalysts for Industrial Applications.

Science.gov (United States)

Borrelli, Grazia M; Trono, Daniela

2015-09-01

Lipases and phospholipases are interfacial enzymes that hydrolyze hydrophobic ester linkages of triacylglycerols and phospholipids, respectively. In addition to their role as esterases, these enzymes catalyze a plethora of other reactions; indeed, lipases also catalyze esterification, transesterification and interesterification reactions, and phospholipases also show acyltransferase, transacylase and transphosphatidylation activities. Thus, lipases and phospholipases represent versatile biocatalysts that are widely used in various industrial applications, such as for biodiesels, food, nutraceuticals, oil degumming and detergents; minor applications also include bioremediation, agriculture, cosmetics, leather and paper industries. These enzymes are ubiquitous in most living organisms, across animals, plants, yeasts, fungi and bacteria. For their greater availability and their ease of production, microbial lipases and phospholipases are preferred to those derived from animals and plants. Nevertheless, traditional purification strategies from microbe cultures have a number of disadvantages, which include non-reproducibility and low yields. Moreover, native microbial enzymes are not always suitable for biocatalytic processes. The development of molecular techniques for the production of recombinant heterologous proteins in a host system has overcome these constraints, as this allows high-level protein expression and production of new redesigned enzymes with improved catalytic properties. These can meet the requirements of specific industrial process better than the native enzymes. The purpose of this review is to give an overview of the structural and functional features of lipases and phospholipases, to describe the recent advances in optimization of the production of recombinant lipases and phospholipases, and to summarize the information available relating to their major applications in industrial processes.

Recombinant Lipases and Phospholipases and Their Use as Biocatalysts for Industrial Applications

Directory of Open Access Journals (Sweden)

Grazia M. Borrelli

2015-09-01

Full Text Available Lipases and phospholipases are interfacial enzymes that hydrolyze hydrophobic ester linkages of triacylglycerols and phospholipids, respectively. In addition to their role as esterases, these enzymes catalyze a plethora of other reactions; indeed, lipases also catalyze esterification, transesterification and interesterification reactions, and phospholipases also show acyltransferase, transacylase and transphosphatidylation activities. Thus, lipases and phospholipases represent versatile biocatalysts that are widely used in various industrial applications, such as for biodiesels, food, nutraceuticals, oil degumming and detergents; minor applications also include bioremediation, agriculture, cosmetics, leather and paper industries. These enzymes are ubiquitous in most living organisms, across animals, plants, yeasts, fungi and bacteria. For their greater availability and their ease of production, microbial lipases and phospholipases are preferred to those derived from animals and plants. Nevertheless, traditional purification strategies from microbe cultures have a number of disadvantages, which include non-reproducibility and low yields. Moreover, native microbial enzymes are not always suitable for biocatalytic processes. The development of molecular techniques for the production of recombinant heterologous proteins in a host system has overcome these constraints, as this allows high-level protein expression and production of new redesigned enzymes with improved catalytic properties. These can meet the requirements of specific industrial process better than the native enzymes. The purpose of this review is to give an overview of the structural and functional features of lipases and phospholipases, to describe the recent advances in optimization of the production of recombinant lipases and phospholipases, and to summarize the information available relating to their major applications in industrial processes.

Ageing studies of resistive Micromegas detectors for the HL-LHC

CERN Document Server

Galán, J; Ferrer-Ribas, E; Giganon, A; Giomataris, I; Herlant, S; Jeanneau, F; Peyaud, A; Schune, Ph; Alexopoulos, T; Byszewski, M; Iakovidis, G; Iengo, P; Ntekas, K; Leontsinis, S; de Oliveira, R; Tsipolitis, Y; Wotschack, J

2013-01-01

Resistive-anode Micromegas detectors are in development since several years, in an effort to solve the problem of sparks when working in high flux and high radiations environment like in the HL-LHC (ten times the luminosity of the LHC). They have been chosen as one of the technologies that will be part of the ATLAS New Small Wheel project (forward muon system). An ageing study is mandatory to assess their capabilities to handle the HL-LHC environment on a long-term period. A prototype has been exposed to several types of irradiations (X-rays, cold neutrons, 60 Co gammas) up to an equivalent HL-LHC time of more than five years without showing any degradation of the performances in terms of gain and energy resolution. Beam test studies took place in October 2012 to assess the tracking performances (efficiency, spatial resolution,...). Results of ageing studies and beam test performances are reported in this paper.

Super and ferric: the first HL-LHC component is ready

CERN Multimedia

Antonella Del Rosso

2016-01-01

Although the actual installation phase in the tunnel will only start in 2024, the first magnet – a sextupole – of the High-Luminosity LHC (HL-LHC) is ready and working according to specifications. This first component is also rather unique as, unlike the superconducting magnets currently used in the LHC, it relies on a “superferric” heart.   An expert in the LASA Laboratory (INFN Milan, Italy) works on assembling the first sextupole corrector of the HL-LHC. (Image: INFN Milan) Although the name might sound completely unfamiliar, superferric magnets were first proposed in the 1980s as a possible solution for high-energy colliders. However, many technical problems had to be overcome before the use of superferric magnets could become a reality. In its final configuration, the HL-LHC will have 36 superferric corrector magnets, of which 4 will be quadrupoles, 8 sextupoles and 24 higher order magnets. In superferric (or “iron-dominated”) magne...

Properties of a membrane-bound triglyceride lipase of rapeseed (Brassica napus L.) cotyledons.

Science.gov (United States)

Rosnitschek, I; Theimer, R R

1980-04-01

The properties of the alkaline lipase activity (EC 3.1.1.3) that was recovered almost completely from a microsomal membrane fraction of 4-d-old rapeseed (Brassica napus L.) cotyledons were studied employing a titrimetric test procedure. The apparent KM was 6.5 mmol l(-1), with emulgated sunflower oil as the substrate. The products of triglyceride hydrolysis in vitro were glycerol, free fatty acids, and minor amounts of mono- and diglycerides. Maximum lipase activity depended on the preincubation of the lipolytic membrane fraction in 0.15 mol l(-1) NaCl and on the presence of at least 0.1 mol l(-1) NaCl in the test mixture. Desoxycholate and up to 0.1 mol l(-1) CaCl2 also activated the enzyme while EDTA and detergents such as trito x-100, digitonin, tween 85, and sodium dodecylsulfate were inhibitory. The rapeseed lipase displayed a conspicuous substrate selectivity among different plant triglycerides; the activity was inversely correlated with the oleic acid content of the oils. Water-soluble triacetin and the phospholipid lecithin were not hydrolyzed. Increasing amounts of free fatty acids reduced lipase activity; erucic acid, a major component of rapeseed oil, exhibited the strongest effect, suggesting a possible role in the regulation of lipase activity in vivo. The data demonstrate that the lipolytic membrane fraction houses a triglyceride lipase with properties similar to other plant and animal lipases. It can both qualitatively and quantitatively account for the fat degradation in rapeseed cotyledons. The evidence that provides further reason to acknowledge the membranous appendices of the spherosomes as the intracellular site of lipolysis is discussed.

Synthesis and Structures of Two Lanthanide Complexes Containing a Mixed Ligand System: [Ln(Phen)2(L)3(HL)]·H2O [Ln = La, Ce; Phen = Phenanthroline; HL = Salicylic Acid

International Nuclear Information System (INIS)

Iravani, Effat; Nami, Navabeh; Nabizadeh, Fatemeh; Bayani, Elham; Neumueller, Bernhard

2013-01-01

The reaction of LnCl 3 ·7H 2 O [Ln = La (1), Ce (2)] with salicylic acid (HL) and 1,10-phenanthroline (Phen) at 20 .deg. C in H 2 O/ethanol gave after work-up and recrystallization two novel lanthanide complexes with general formula [Ln(Phen) 2 (L) 3 (HL)]·H 2 O. Compounds 1 and 2 were characterized by IR and UV-Vis spectroscopy, TGA, CHN as well as by X-ray analysis. According to these results, compounds 1 and 2 are isostructural and contain Ln 3+ ions with coordination number nine. Complexes 1 and 2 consist of two Phen, one neutral HL and three L anions (two L anions act as monodentate ligands and the third one is chelating to Ln 3+ ). Thermal decomposition led to primary loss of the Phen molecules. Then HL molecules and finally L moieties left the material to give Ln 2 O 3

Hydrolysis of mixed monomolecular films of triglyceride/lecithin by pancreatic lipase.

Science.gov (United States)

Pieroni, G; Verger, R

1979-10-25

The main purpose of this study was to describe the influence of lecithin upon lipolysis of mixed monomolecular films of trioctanoylglycerol/didodecanoylphosphatidycholine by pancreatic lipase in order to mimic some physiological situations. The quantity of enzyme adsorbed to the interface was simultaneously determined using 5-thio-2-nitro[14C]benzoyl lipase. Lipolytic activity was enhanced 3- to 4-fold in the presence of colipase, an effect which is attributed to increased enzyme turnover number. When a pure triglyceride film was progressively diluted with lecithin, the minimum specific activity of lipase exhibited a bell-shaped curve: a mixed film containing only 20% trioctanoylglycerol was hydrolyzed at the same rate as a monolayer of pure triglyceride.

New member of the hormone-sensitive lipase family from the permafrost microbial community.

Science.gov (United States)

Petrovskaya, Lada E; Novototskaya-Vlasova, Ksenia A; Gapizov, Sultan Sh; Spirina, Elena V; Durdenko, Ekaterina V; Rivkina, Elizaveta M

2017-07-04

Siberian permafrost is a unique environment inhabited with diverse groups of microorganisms. Among them, there are numerous producers of biotechnologically relevant enzymes including lipases and esterases. Recently, we have constructed a metagenomic library from a permafrost sample and identified in it several genes coding for potential lipolytic enzymes. In the current work, properties of the recombinant esterases obtained from this library are compared with the previously characterized lipase from Psychrobacter cryohalolentis and other representatives of the hormone-sensitive lipase family.

From Structure to Catalysis: Recent Developments in the Biotechnological Applications of Lipases

Directory of Open Access Journals (Sweden)

Cristiane D. Anobom

2014-01-01

Full Text Available Microbial lipases are highly appreciated as biocatalysts due to their peculiar characteristics such as the ability to utilize a wide range of substrates, high activity and stability in organic solvents, and regio- and/or enantioselectivity. These enzymes are currently being applied in a variety of biotechnological processes, including detergent preparation, cosmetics and paper production, food processing, biodiesel and biopolymer synthesis, and the biocatalytic resolution of pharmaceutical derivatives, esters, and amino acids. However, in certain segments of industry, the use of lipases is still limited by their high cost. Thus, there is a great interest in obtaining low-cost, highly active, and stable lipases that can be applied in several different industrial branches. Currently, the design of specific enzymes for each type of process has been used as an important tool to address the limitations of natural enzymes. Nowadays, it is possible to “order” a “customized” enzyme that has ideal properties for the development of the desired bioprocess. This review aims to compile recent advances in the biotechnological application of lipases focusing on various methods of enzyme improvement, such as protein engineering (directed evolution and rational design, as well as the use of structural data for rational modification of lipases in order to create higher active and selective biocatalysts.

Hydrolysis products generated by lipoprotein lipase and endothelial lipase differentially impact THP-1 macrophage cell signalling pathways.

Science.gov (United States)

Essaji, Yasmin; Yang, Yanbo; Albert, Carolyn J; Ford, David A; Brown, Robert J

2013-08-01

Macrophages express lipoprotein lipase (LPL) and endothelial lipase (EL) within atherosclerotic plaques; however, little is known about how lipoprotein hydrolysis products generated by these lipases might affect macrophage cell signalling pathways. We hypothesized that hydrolysis products affect macrophage cell signalling pathways associated with atherosclerosis. To test our hypothesis, we incubated differentiated THP-1 macrophages with products from total lipoprotein hydrolysis by recombinant LPL or EL. Using antibody arrays, we found that the phosphorylation of six receptor tyrosine kinases and three signalling nodes--most associated with atherosclerotic processes--was increased by LPL derived hydrolysis products. EL derived hydrolysis products only increased the phosphorylation of tropomyosin-related kinase A, which is also implicated in playing a role in atherosclerosis. Using electrospray ionization-mass spectrometry, we identified the species of triacylglycerols and phosphatidylcholines that were hydrolyzed by LPL and EL, and we identified the fatty acids liberated by gas chromatography-mass spectrometry. To determine if the total liberated fatty acids influenced signalling pathways, we incubated differentiated THP-1 macrophages with a mixture of the fatty acids that matched the concentrations of liberated fatty acids from total lipoproteins by LPL, and we subjected cell lysates to antibody array analyses. The analyses showed that only the phosphorylation of Akt was significantly increased in response to fatty acid treatment. Overall, our study shows that macrophages display potentially pro-atherogenic signalling responses following acute treatments with LPL and EL lipoprotein hydrolysis products.

Mathematical modeling of lipase and protease production by Penicillium restrictum in a batch fermenter.

Science.gov (United States)

Freire, D M; Sant'Anna, G L; Alves, T L

1999-01-01

This work presents a mathematical model that describes time course variations of extracellular lipase and protease activities for the batch fermentation of the fungus Penicillium restrictum, a new and promising strain isolated from soil and wastes of a Brazilian babassu coconut oil industry. The fermentation process was modeled by an unstructured model, which considered the following dependent variables: cells, fat acid, dissolved oxygen concentrations, lipase and protease activities, and cell lysate concentration. The last variable represents the amount of cells that has been lysed by the shear stress and natural cell death. Proteases released to the medium, as consequence of this process, enhance lipase inactivation. The model is able to predict the effects of some operation variables such as air flow rate and agitation speed. The mathematical model was validated against batch-fermentation data obtained under several operating conditions. Because substrate concentration has antagonistic effects on lipase activity, a typical optimization scheme should be developed in order to minimize these deleterious effects while maximizing lipase activity.

Development of a high-throughput assay for measuring lipase activity using natural triacylglycerols coated on microtiter plates.

Science.gov (United States)

Serveau-Avesque, Carole; Verger, Robert; Rodriguez, Jorge A; Abousalham, Abdelkarim

2013-09-21

We have designed a convenient, specific, sensitive and continuous lipase assay based on the use of natural triacylglycerols (TAGs) from the Aleurites fordii seed oil which contains α-eleostearic acid (9,11,13,cis,trans,trans-octadecatrienoic acid) and which was coated in the wells of microtiter plates. The coated TAG film cannot be desorbed by the various buffers used during the lipase assay. Upon lipase action, α-eleostearic acid is liberated and desorbed from the interface and then solubilized into the micellar phase. Consequently, the UV absorbance of the α-eleostearic acid is considerably enhanced due to the transformation from an adsorbed to a water soluble state. The lipase activity can be measured continuously by recording the variations with time of the UV absorption spectra. The rate of lipolysis was monitored by measuring the increase of OD at 272 nm, which was found to be linear with time and directly proportional to the amount of added lipase. This microtiter plate lipase assay, based on coated TAGs, presents various advantages as compared to the classical systems: (i) coated TAGs on the microtiter plates could be stored for a long-time at 4 °C, (ii) higher sensitivity in lipase detection, (iii) good reproducibility, and (iv) increase of signal to noise ratio due to high UV absorption after transfer of α-eleostearic acid from an adsorbed to a soluble state. Low concentrations, down to 1 pg mL(-1) of pure Thermomyces lanuginosus or human pancreatic lipase, could be detected under standard assay conditions. The detection sensitivity of this coated method is around 1000 times higher as compared to those obtained with the classical emulsified systems. This continuous high throughput lipase assay could be used to screen new lipases and/or lipase inhibitors present in various biological samples.

Comparative genomic analysis of the Lipase3 gene family in five plant species reveals distinct evolutionary origins.

Science.gov (United States)

Wang, Dan; Zhang, Lin; Hu, JunFeng; Gao, Dianshuai; Liu, Xin; Sha, Yan

2018-04-01

Lipases are physiologically important and ubiquitous enzymes that share a conserved domain and are classified into eight different families based on their amino acid sequences and fundamental biological properties. The Lipase3 family of lipases was reported to possess a canonical fold typical of α/β hydrolases and a typical catalytic triad, suggesting a distinct evolutionary origin for this family. Genes in the Lipase3 family do not have the same functions, but maintain the conserved Lipase3 domain. There have been extensive studies of Lipase3 structures and functions, but little is known about their evolutionary histories. In this study, all lipases within five plant species were identified, and their phylogenetic relationships and genetic properties were analyzed and used to group them into distinct evolutionary families. Each identified lipase family contained at least one dicot and monocot Lipase3 protein, indicating that the gene family was established before the split of dicots and monocots. Similar intron/exon numbers and predicted protein sequence lengths were found within individual groups. Twenty-four tandem Lipase3 gene duplications were identified, implying that the distinctive function of Lipase3 genes appears to be a consequence of translocation and neofunctionalization after gene duplication. The functional genes EDS1, PAD4, and SAG101 that are reportedly involved in pathogen response were all located in the same group. The nucleotide diversity (Dxy) and the ratio of nonsynonymous to synonymous nucleotide substitutions rates (Ka/Ks) of the three genes were significantly greater than the average across the genomes. We further observed evidence for selection maintaining diversity on three genes in the Toll-Interleukin-1 receptor type of nucleotide binding/leucine-rich repeat immune receptor (TIR-NBS LRR) immunity-response signaling pathway, indicating that they could be vulnerable to pathogen effectors.

Performance and Operational Aspects of HL-LHC Scenarios

CERN Document Server

Medina Medrano, Luis

2016-01-01

Several alternatives to the present HL-LHC baseline configuration have been proposed, aiming either to improve the potential performance, reduce its risks, or to provide options for addressing possible limitations or changes in its parameters. In this paper we review and compare the performance of the HL-LHC baseline and the main alternatives with the latest parameters set. The results are obtained using refined simulations of the evolution of the luminosity with β^{*}-levelling, for which new criteria have been introduced, such as improved calculation of the intrabeam scattering and the addition of penalty steps to take into account the necessary time to move between consecutive optics during the process. The features of the set of optics are discussed for the nominal baseline.

Binding orientation and interaction of bile salt in its ternary complex with pancreatic lipase-colipase system.

Science.gov (United States)

Haque, Neshatul; Prakash Prabhu, N

2018-05-23

The interfacial activity of pancreatic lipases (PL) depends on the presence of colipase and bile salt. The activity of PL is inhibited by micellar concentrations of bile salt which can be restored by the addition of colipase. Though the formation of 1:1:1 tertiary complex by lipase-colipase-bile salt micelle is well accepted, the residue-level interactions between lipase-colipase and bile salt are yet to be clearly understood. Molecular dynamic simulations of lipase-colipase complex, lipase and colipase were performed in the presence of a model bile salt, sodium taurocholate (NaTC), at its near-CMC and supra-micellar concentrations. From the interactions obtained from the molecular dynamic simulations, the ternary complex was modelled and compared with earlier reports. The analysis suggested that a micelle of NaTC consisting of nine monomers was formed at the concave groove between lipase and colipase chain and it mainly interacted with the fourth finger of colipase. This complex was mainly stabilized by van der Waals interactions. Interestingly, the C-terminal domain of lipase which holds the colipase did not show any significant role in formation or stabilization of NaTC micelle. Copyright © 2018 Elsevier Inc. All rights reserved.

Performances of the HL (Hyperloop) transport system

NARCIS (Netherlands)

van Goeverden, C.D.; Milakis, D.; Janic, M.; Konings, J.W.; Cools, M.; Limbourg, S.

2017-01-01

This paper deals with an analysis of performances of the HL (Hyperloop) transport system considered as an advanced transport alternative to the existing APT (Air Passenger Transport) and HSR (High Speed Rail) systems. The considered performances are operational, financial, social and environmental.

Biochemical Properties of a New Cold-Active Mono- and Diacylglycerol Lipase from Marine Member Janibacter sp. Strain HTCC2649

Directory of Open Access Journals (Sweden)

Dongjuan Yuan

2014-06-01

Full Text Available Mono- and di-acylglycerol lipase has been applied to industrial usage in oil modification for its special substrate selectivity. Until now, the reported mono- and di-acylglycerol lipases from microorganism are limited, and there is no report on the mono- and di-acylglycerol lipase from bacteria. A predicted lipase (named MAJ1 from marine Janibacter sp. strain HTCC2649 was purified and biochemical characterized. MAJ1 was clustered in the family I.7 of esterase/lipase. The optimum activity of the purified MAJ1 occurred at pH 7.0 and 30 °C. The enzyme retained 50% of the optimum activity at 5 °C, indicating that MAJ1 is a cold-active lipase. The enzyme activity was stable in the presence of various metal ions, and inhibited in EDTA. MAJ1 was resistant to detergents. MAJ1 preferentially hydrolyzed mono- and di-acylglycerols, but did not show activity to triacylglycerols of camellia oil substrates. Further, MAJ1 is low homologous to that of the reported fungal diacylglycerol lipases, including Malassezia globosa lipase 1 (SMG1, Penicillium camembertii lipase U-150 (PCL, and Aspergillus oryzae lipase (AOL. Thus, we identified a novel cold-active bacterial lipase with a sn-1/3 preference towards mono- and di-acylglycerides for the first time. Moreover, it has the potential, in oil modification, for special substrate selectivity.

Properties of Immobilized Candida antarctica Lipase B on Highly Macroporous Copolymer

International Nuclear Information System (INIS)

Handayani, N.; Achmad, S.; Wahyuningrum, D.

2011-01-01

In spite of their excellent catalytic properties, enzymes should be improved before their implementation both in industrial and laboratorium scales. Immobilization of enzyme is one of the ways to improve their properties. Candida antarctica lipase B (Cal-B) has been reported in numerous publications to be a particularly useful enzyme catalizing in many type of reaction including regio- and enantio- synthesis. For this case, cross-linking of immobilized Cal-B with 1,2,7,8 diepoxy octane is one of methods that proved significantly more stable from denaturation by heat, organic solvents, and proteolysis than lyophilized powder or soluble enzymes. More over, the aim of this procedure is to improve the activity and reusability of lipase. Enzyme kinetics test was carried out by transesterification reaction between 4-nitrophenyl acetate (pNPA) and methanol by varying substrate concentrations, and the result is immobilized enzymes follows the Michaelis-Menten models and their activity is match with previous experiment. Based on the V max values, the immobilized enzymes showed higher activity than the free enzyme. Cross-linking of immobilized lipase indicate that cross-linking by lower concentration of cross-linker, FIC (immobilized lipase that was incubated for 24 h) gave the highest activity and cross-linking by higher concentration of cross-linker, PIC (immobilized lipase that was incubated for 2 h) gives the highest activity. However, pore size and saturation level influenced their activity. (author)

A plasmonic nanosensor for lipase activity based on enzyme-controlled gold nanoparticles growth in situ

Science.gov (United States)

Tang, Yan; Zhang, Wei; Liu, Jia; Zhang, Lei; Huang, Wei; Huo, Fengwei; Tian, Danbi

2015-03-01

A plasmonic nanosensor for lipase activity was developed based on one-pot nanoparticle growth. Tween 80 was selected not only as the substrate for lipase recognition but also as the reducing and stabilizing agent for the sensor fabrication. The different molecular groups in Tween 80 could have different roles in the fabrication procedure; the H2O2 produced by the autoxidation of the ethylene oxide subunits in Tween 80 could reduce the AuCl4- ions to Au atoms, meanwhile, the lipase could hydrolyze its carboxyl ester bond, which could, in turn, control the rate of nucleation of the gold nanoparticles (AuNPs) and tailor the localized surface plasmon resonance (LSPR) of the AuNP transducers. The color changes, which depend on the absence or presence of the lipase, could be used to sense the lipase activity. A linear response ranging from 0.025 to 4 mg mL-1 and a detection limit of the lipase as low as 3.47 μg mL-1 were achieved. This strategy circumvents the problems encountered by general enzyme assays that require sophisticated instruments and complicated assembling steps. The methodology can benefit the assays of heterogeneous-catalyzed enzymes.A plasmonic nanosensor for lipase activity was developed based on one-pot nanoparticle growth. Tween 80 was selected not only as the substrate for lipase recognition but also as the reducing and stabilizing agent for the sensor fabrication. The different molecular groups in Tween 80 could have different roles in the fabrication procedure; the H2O2 produced by the autoxidation of the ethylene oxide subunits in Tween 80 could reduce the AuCl4- ions to Au atoms, meanwhile, the lipase could hydrolyze its carboxyl ester bond, which could, in turn, control the rate of nucleation of the gold nanoparticles (AuNPs) and tailor the localized surface plasmon resonance (LSPR) of the AuNP transducers. The color changes, which depend on the absence or presence of the lipase, could be used to sense the lipase activity. A linear response

Concept design for the central control system of HL-2A

International Nuclear Information System (INIS)

Song Xianming; Li Qiang; Jiang Chao

2001-01-01

The design principle and basic structure of the central control system for HL-2A Tokamak are introduced. Having been limited by manpower and money, the central control system should not be too expensive and too advanced. On the other hand, because of the complexity of the machine and the difficulty the author will encounter when operating the machine, the central control system should be advanced enough. If use the same technology for HL-1M to control HL-2A, the author would fail to fulfill authors' experiment goal. The central control system consists of software and hardware. The software mainly includes: (a) system monitor and control software; (b) discharge monitor and control software; (c) network and communication software. Hardware includes: (a) PLC for machine control, personnel protection and machine protection; and (b) VME computer, for the feedback control of the discharge

Canine Pancreas-Specific Lipase and C-reactive Protein in Dogs Treated With Anticonvulsants (Phenobarbital and Potassium Bromide).

Science.gov (United States)

Albarracín, Viviana; Teles, Mariana; Meléndez-Lazo, Antonio; Rodón, Jaume; Pastor, Josep

2015-06-01

Animals treated with anticonvulsant drugs may have increased canine pancreas-specific lipase (cPLI) values. Inflammatory conditions and specifically acute pancreatitis are of major concern in these animals. Elevation in C-reactive protein is being associated with inflammatory status in dogs and it has been correlated with the clinical severity of pancreatitis. In the present study, we investigated if there is a correlation between the cPLI increase, changes in C-reactive protein and hepatic enzymes, as well as the incidence of severe acute pancreatitis (AP) in dogs with anticonvulsant treatment (phenobarbital, or potassium bromide or both). Increased values of pancreas-specific lipase were found in 6.8% of the animals in treatment with anticonvulsants, and this increase is correlated with the increase in triglycerides, alkaline phosphatase, and alanine aminotransferase but not with C-reactive protein levels, which suggests a possible induction or release phenomenon rather than a clear severe AP. C-reactive protein levels did not affect cPLI values on the population studied. Only 2 animals had clinical and analytical data suggestive of AP, indicating a low prevalence (0.6%). In conclusion, cPLI may be increased in a low percentage of animals with anticonvulsants treatment and its increase may not be associated with severe AP. It may be induced by the anticonvulsants drugs; however, further studies are advised to rule out other possible causes that increased cPLI. Copyright © 2015 Elsevier Inc. All rights reserved.

Characterized the pattern of the material deposition in the HL-2A tokamak

Energy Technology Data Exchange (ETDEWEB)

Cai, Laizhong, E-mail: cailz@swip.ac.cn [Southwestern Institute of Physics, P.O.Box 432, Chengdu, Sichuan 610041 (China); Wang, Jianbao; Wu, Ting; Zeng, Xiaoxiao [Southwestern Institute of Physics, P.O.Box 432, Chengdu, Sichuan 610041 (China); Hai, Ran; Ding, Hongbin [Dalian University of Technology, Dalian, Liaoning 116024 (China)

2017-03-15

Since the divertor geometry of a tokamak has a strong impact on the material erosion and deposition on the wall and HL-2A has a unique divertor configuration, it is necessary to investigate the material deposition pattern in HL-2A although a few results on other tokamaks have already been published. In this paper, tiles retrieved from the vessel are analyzed ex-situ by SIMS, SEM and laser-induced breakdown spectroscopy (LIBS). And deposition behind the lower divertor is in-situ measured by a quartz crystal microbalance (QMB). The deposition in HL-2A displays a complex pattern and clear localization characteristic. The thickness of the deposition layer varies in the range of 0-4μm. And in-situ diagnostic of QMB indicates that the average thickness of the deposition layer per pulse is over ten nanometers. In addition, the results imply that Si, Fe and D have different behaviors during the material deposition in HL-2A.

Factors influencing production of lipase under metal supplementation by bacterial strain, Bacillus subtilis BDG-8.

Science.gov (United States)

Dhevahi, B; Gurusamy, R

2014-11-01

Lipases are biocatalyst having wide applications in industries due to their versatile properties. In the present study, a lipolytic bacterial strain, Bacillus subtilis BDG-8 was isolated from an oil based industrial soil. The effect of selenium and nickel as a media supplement on enhancement of lipase production, was studied individually with the isolated strain by varying the concentration of selected metal. 60 μg l(-1) selenium enhanced lipase production to an enzyme activity measuring 7.8 U ml(-1) while 40 μgI(-1) nickel gave the maximum enzyme activity equivalent to 7.5 U ml(-1). However, nickel and selenium together at a range of concentration with an equal w/v ratio, at 60 μg l(-1) each, showed the maximum lipase activity of 8.5 U ml(-1). The effect of pH and temperature on lipase production showed maximum enzyme activity in the presence of each of the metals at pH 7 and 35°C among the other tested ranges. After optimisation of the parameters such as metal concentration, pH and temperature lipase production by Bacillus subtilis BDG-8 had increased several folds. This preliminary investigation may consequently lead as to various industrial applications such as treatment of wastewater contaminated with metal or oil with simultaneous lipase production.

Production of Thermoalkaliphilic Lipase from Geobacillus thermoleovorans DA2 and Application in Leather Industry

OpenAIRE

Abol Fotouh, Deyaa M.; Bayoumi, Reda A.; Hassan, Mohamed A.

2016-01-01

Thermophilic and alkaliphilic lipases are meeting a growing global attention as their increased importance in several industrial fields. Over 23 bacterial strains, novel strain with high lipolytic activity was isolated from Southern Sinai, Egypt, and it was identified as Geobacillus thermoleovorans DA2 using 16S rRNA as well as morphological and biochemical features. The lipase was produced in presence of fatty restaurant wastes as an inducing substrate. The optimized conditions for lipase pr...

Classification of EC 3.1.1.3 bacterial true lipases using phylogenetic ...

African Journals Online (AJOL)

To obtain an overview of this industrially and very important class of enzymes and their characteristics, we collected and classified bacterial lipases sequences available from protein databases. Here we proposed an updated and revised classification of family I bacterial "true" lipases based mainly on a comparison of their ...

Hepatic fat accumulation and regulation of FAT/CD36: an effect of hepatic irradiation

Science.gov (United States)

Martius, Gesa; Alwahsh, Salamah Mohammad; Rave-Fränk, Margret; Hess, Clemens Friedrich; Christiansen, Hans; Ramadori, Giuliano; Malik, Ihtzaz Ahmed

2014-01-01

Irradiation is known to induce inflammation and affect fat metabolic pathways. The current study investigates hepatic fat accumulation and fatty acid transportation in a rat model of single dose liver irradiation (25-Gy). Rat livers were selectively irradiated in-vivo (25-Gy), sham-irradiated rats served as controls. Hepatic lipids were studied by colorimetric assays in liver and serum. Intracellular lipids, protein and mRNA were studied by Nile red staining, immunohistology, Western Blot analysis and RT-PCR in liver, respectively. Changes in FAT/CD36 expression were studied in-vitro in a human monocyte cell line U937 after irradiation in presence or absence of infliximab (IFX). Nile Red staining of liver cryosections showed a quick (12-48 h) increase in fat droplets. Accordingly, hepatic triglycerides (TG) and free fatty acids (FFA) were elevated. An early increase (3-6 h) in the serum level of HDL-C, TG and cholesterol was measured after single dose irradiation followed by a decrease thereafter. Furthermore, expression of the fat transporter protein FAT/CD36 was increased, immunohistochemistry revealed basolateral and cytoplasmic expression in hepatocytes. Moreover, apolipoprotein-B100, -C3 and enzymes (acetyl-CoA carboxylase, lipoprotein-lipase, carnitine-palmitoyltransferase, malonyl-CoA-decarboxylase) involved in fat metabolism were induced at 12-24 h. Early activation of the NFkβ pathway (IκBα) by TNF-α was seen, followed by a significant elevation of serum markers for liver damage (AST and GLDH). TNF-α blockage by anti-TNF-α in cell culture (U937) prevented the increase of FAT/CD36 caused by irradiation. Selective liver irradiation is a model for rapid induction of steatosis hepatis and fat accumulation could be triggered by irradiation-induced inflammatory mediators (e.g. TNF-α). PMID:25197426

Enhancing activity and thermostability of lipase A from Serratia marcescens by site-directed mutagenesis.

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Mohammadi, Mohsen; Sepehrizadeh, Zargham; Ebrahim-Habibi, Azadeh; Shahverdi, Ahmad Reza; Faramarzi, Mohammad Ali; Setayesh, Neda

2016-11-01

Lipases as significant biocatalysts had been widely employed to catalyze various chemical reactions such as ester hydrolysis, ester synthesis, and transesterification. Improving the activity and thermostability of enzymes is desirable for industrial applications. The lipase of Serratia marcescens belonging to family I.3 lipase has a very important pharmaceutical application in production of chiral precursors. In the present study, to achieve improved lipase activity and thermostability, using computational predictions of protein, four mutant lipases of SML (MutG2P, MutG59P, Mut H279K and MutL613WA614P) were constructed by site-directed mutagenesis. The recombinant mutant proteins were over-expressed in E. coli and purified by affinity chromatography on the Ni-NTA system. Circular dichroism spectroscopy, differential scanning calorimetry and kinetic parameters (Km and kcat) were determined. Our results have shown that the secondary structure of all lipases was approximately similar to one another. The MutG2P and MutG59P were more stable than wild type by approximately 2.3 and 2.9 in T 1/2 , respectively. The catalytic efficiency (kcat/Km) of MutH279K was enhanced by 2-fold as compared with the wild type (p<0.05). These results indicate that using protein modeling program and creating mutation, can enhance lipase activity and/or thermostability of SML and it also could be used for improving other properties of enzyme to the desired requirements as well as further mutations. Copyright © 2016 Elsevier Inc. All rights reserved.

HL-217, a new topical anti-angiogenic agent, inhibits retinal vascular leakage and pathogenic subretinal neovascularization in Vldlr−/− mice

International Nuclear Information System (INIS)

Kim, Junghyun; Kim, Chan-Sik; Jo, Kyuhyung; Cho, Yun-Seok; Kim, Hyun-Gyu; Lee, Geun-Hyeog; Lee, Yun Mi; Sohn, Eunjin; Kim, Jin Sook

2015-01-01

Highlights: • HL-217 is a new synthetic topical anti-angiogenic agent. • HL-217 attenuated subretinal neovascularization in Vldlr −/− mice. • HL-217 blocked the binding of PDGF-BB to PDGFRβ. - Abstract: HL-217 is a new synthetic angiogenesis inhibitor. Platelet derived growth factor (PDGF) is a vasoactive factor and has been implicated in proliferative retinopathies. In this study, we examined the mechanism of action and efficacy of topical application of HL-217 on subretinal neovascularization in very low-density lipoprotein receptor knockout (Vldlr −/− ) mice. In three-week-old male Vldlr −/− mice, HL-217 (1.5 or 3 mg/ml) was administered twice per day for 4 weeks by topical eye drop instillation. Neovascular areas were then measured. We used a protein array to evaluate the expression levels of angiogenic factors. The inhibitory effect of HL-217 on the PDGF-BB/PDGFRβ interaction was evaluated in vitro. The neovascular area in the Vldlr −/− mice was significantly reduced by HL-217. Additionally, HL-217 decreased the expression levels of PDGF-BB protein and VEGF mRNA. Moreover, HL-217 dose-dependently inhibited the PDGF-BB/PDGFRβ interaction (IC 50 = 38.9 ± 0.7 μM). These results suggest that HL-217 is a potent inhibitor of PDGF-BB. HL-217, when applied topically, is an effective inhibitor of subretinal neovascularization due to its ability to inhibit the pro-angiogenic effects of PDGF-BB

Lipase catalyzed transesterification of castor oil by straight chain higher alcohols.

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Malhotra, Deepika; Mukherjee, Joyeeta; Gupta, Munishwar N

2015-03-01

Biolubricants from Castor oil were produced enzymatically by transesterification with higher alcohols using a lipase mixture of immobilized Mucor miehei (RMIM) and immobilized Candida antarctica lipase B (Novozym 435) under low water conditions. The conversions were in the range of 80-95% under the optimized conditions. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Production of Biodiesel Using Immobilized Lipase and the Characterization of Different Co-Immobilizing Agents and Immobilization Methods

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Kang Zhao

2016-08-01

Full Text Available Lipase from Candida sp. 99–125 is widely employed to catalyzed transesterification and can be used for biodiesel production. In this study, the lipase was immobilized by combined adsorption and entrapment to catalyze biodiesel production from waste cooking oil (WCO via transesterification, and investigating co-immobilizing agents as additives according to the enzyme activity. The addition of the mixed co-immobilizing agents has positive effects on the activities of the immobilized lipase. Three different immobilizing methods were compared by the conversion ratio of biodiesel and structured by Atom Force Microscopy (AFM and Scanning Electron Microscopy (SEM, respectively. It was found that entrapment followed by adsorption was the best method. The effect of the co-immobilizing agent amount, lipase dosage, water content, and reuse ability of the immobilized lipase was investigated. By comparison with previous research, this immobilized lipase showed good reuse ability: the conversion ratio excesses 70% after 10 subsequent reactions, in particular, was better than Novozym435 and TLIM on waste cooking oil for one unit of lipase.

Immobilised lipases in the cosmetics industry.

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Ansorge-Schumacher, Marion B; Thum, Oliver

2013-08-07

Commercial products for personal care, generally perceived as cosmetics, have an important impact on everyday life worldwide. Accordingly, the market for both consumer products and specialty chemicals comprising their ingredients is considerable. Lipases have started to play a minor role as active ingredients in so-called 'functional cosmetics' as well as a major role as catalysts for the industrial production of various specialty esters, aroma compounds and active agents. Interestingly, both applications almost always require preparation by appropriate immobilisation techniques. In addition, for catalytic use special reactor concepts often have to be employed due to the mostly limited stability of these preparations. Nevertheless, these processes show distinct advantages based on process simplification, product quality and environmental footprint and are therefore apt to more and more replace traditional chemical processes. Here, for the first time a review on the various aspects of using immobilised lipases in the cosmetics industry is given.

White Pitaya (Hylocereus undatus) Juice Attenuates Insulin Resistance and Hepatic Steatosis in Diet-Induced Obese Mice.

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Song, Haizhao; Zheng, Zihuan; Wu, Jianan; Lai, Jia; Chu, Qiang; Zheng, Xiaodong

2016-01-01

Insulin resistance and hepatic steatosis are the most common complications of obesity. Pitaya is an important source of phytochemicals such as polyphenols, flavonoid and vitamin C which are related to its antioxidant activity. The present study was conducted to evaluate the influence of white pitaya juice (WPJ) on obesity-related metabolic disorders (e.g. insulin resistance and hepatic steatosis) in high-fat diet-fed mice. Forty-eight male C57BL/6J mice were assigned into four groups and fed low-fat diet with free access to water or WPJ, or fed high-fat diet with free access to water or WPJ for 14 weeks. Our results showed that administration of WPJ improved high-fat diet-induced insulin resistance, hepatic steatosis and adipose hypertrophy, but it exerted no influence on body weight gain in mice. Hepatic gene expression analysis indicated that WPJ supplement not only changed the expression profile of genes involved in lipid and cholesterol metabolism (Srebp1, HMGCoR, Cpt1b, HL, Insig1 and Insig2) but also significantly increased the expression levels of FGF21-related genes (Klb, FGFR2, Egr1 and cFos). In conclusion, WPJ protected from diet-induced hepatic steatosis and insulin resistance, which was associated with the improved FGF21 resistance and lipid metabolism.

Expression of caspase-3 gene in apoptotic HL-60 cell and different human tumor cell lines

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Li Xiaoming; Song Tianbao

1999-01-01

Objective: To research the expression of caspase-3 gene in the apoptotic and the control HL-60 cells and in the different human tumor cell lines. Methods: Caspase-3 mRNA in the control and γ-radiation-induced apoptotic HL-60 cells, and in the 6 types of human tumor cell lines, was analysed by Northern blot. Results: The caspase-3 gene transcript was more highly expressed in leukemia cells HL-60, CEM, K562 and neuroblastoma SH-SY5Y than in cervical adenocarcinoma HeLa and breast carcinoma MCF7, and more highly in the radiation-induced apoptotic HL-60 than in the control HL-60 cells. Conclusion: The high level of expression of caspase-3 may aid the efforts to understand the tumor cell sensitivity to radiation, apoptosis and its inherent ability to survive

Uric acid disrupts hypochlorous acid production and the bactericidal activity of HL-60 cells.

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Carvalho, Larissa A C; Lopes, João P P B; Kaihami, Gilberto H; Silva, Railmara P; Bruni-Cardoso, Alexandre; Baldini, Regina L; Meotti, Flavia C

2018-06-01

Uric acid is the end product of purine metabolism in humans and is an alternative physiological substrate for myeloperoxidase. Oxidation of uric acid by this enzyme generates uric acid free radical and urate hydroperoxide, a strong oxidant and potentially bactericide agent. In this study, we investigated whether the oxidation of uric acid and production of urate hydroperoxide would affect the killing activity of HL-60 cells differentiated into neutrophil-like cells (dHL-60) against a highly virulent strain (PA14) of the opportunistic pathogen Pseudomonas aeruginosa. While bacterial cell counts decrease due to dHL-60 killing, incubation with uric acid inhibits this activity, also decreasing the release of the inflammatory cytokines interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF- α). In a myeloperoxidase/Cl - /H 2 O 2 cell-free system, uric acid inhibited the production of HOCl and bacterial killing. Fluorescence microscopy showed that uric acid also decreased the levels of HOCl produced by dHL-60 cells, while significantly increased superoxide production. Uric acid did not alter the overall oxidative status of dHL-60 cells as measured by the ratio of reduced (GSH) and oxidized (GSSG) glutathione. Our data show that uric acid impairs the killing activity of dHL-60 cells likely by competing with chloride by myeloperoxidase catalysis, decreasing HOCl production. Despite diminishing HOCl, uric acid probably stimulates the formation of other oxidants, maintaining the overall oxidative status of the cells. Altogether, our results demonstrated that HOCl is, indeed, the main relevant oxidant against bacteria and deviation of myeloperoxidase activity to produce other oxidants hampers dHL-60 killing activity. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Cell-bound lipases from Burkholderia sp. ZYB002: gene sequence analysis, expression, enzymatic characterization, and 3D structural model.

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Shu, Zhengyu; Lin, Hong; Shi, Shaolei; Mu, Xiangduo; Liu, Yanru; Huang, Jianzhong

2016-05-03

The whole-cell lipase from Burkholderia cepacia has been used as a biocatalyst in organic synthesis. However, there is no report in the literature on the component or the gene sequence of the cell-bound lipase from this species. Qualitative analysis of the cell-bound lipase would help to illuminate the regulation mechanism of gene expression and further improve the yield of the cell-bound lipase by gene engineering. Three predictive cell-bound lipases, lipA, lipC21 and lipC24, from Burkholderia sp. ZYB002 were cloned and expressed in E. coli. Both LipA and LipC24 displayed the lipase activity. LipC24 was a novel mesophilic enzyme and displayed preference for medium-chain-length acyl groups (C10-C14). The 3D structural model of LipC24 revealed the open Y-type active site. LipA displayed 96 % amino acid sequence identity with the known extracellular lipase. lipA-inactivation and lipC24-inactivation decreased the total cell-bound lipase activity of Burkholderia sp. ZYB002 by 42 % and 14 %, respectively. The cell-bound lipase activity from Burkholderia sp. ZYB002 originated from a multi-enzyme mixture with LipA as the main component. LipC24 was a novel lipase and displayed different enzymatic characteristics and structural model with LipA. Besides LipA and LipC24, other type of the cell-bound lipases (or esterases) should exist.

Polyethyleneimine-modified superparamagnetic Fe{sub 3}O{sub 4} nanoparticles for lipase immobilization: Characterization and application

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Khoobi, Mehdi; Motevalizadeh, Seyed Farshad [Department of Medicinal Chemistry, Faculty of Pharmacy and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran 1417614411 (Iran, Islamic Republic of); Asadgol, Zahra [Department of Pharmaceutical Biotechnology, Faculty of Pharmacy and Biotechnology Research Center, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran 1417614411 (Iran, Islamic Republic of); Forootanfar, Hamid [Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman (Iran, Islamic Republic of); Shafiee, Abbas, E-mail: ashafiee@ams.ac.ir [Department of Medicinal Chemistry, Faculty of Pharmacy and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran 1417614411 (Iran, Islamic Republic of); Faramarzi, Mohammad Ali, E-mail: faramarz@tums.ac.ir [Department of Pharmaceutical Biotechnology, Faculty of Pharmacy and Biotechnology Research Center, Tehran University of Medical Sciences, P.O. Box 14155-6451, Tehran 1417614411 (Iran, Islamic Republic of)

2015-01-15

Magnetically separable nanospheres consisting of polyethyleneimine (PEI) and succinated PEI grafted on silica coated magnetite (Fe{sub 3}O{sub 4}) were prepared and characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, vibrating sample magnetometer, scanning electron microscopy and transmission electron microscopy. The prepared magnetic nanoparticles were then applied for physical adsorption or covalent attachment of Thermomyces lanuginosa lipase (TLL) via glutaraldehyde or hexamethylene diisocyanate. The reusability, storage, pH and thermal stabilities of the immobilized enzymes compared to that of free lipase were examined. The obtained results showed that the immobilized lipase on MNPs@PEI-GLU was the best biocatalyst which retained 80% of its initial activity after 12 cycles of application. The immobilized lipase on the selected support (MNPs@PEI-GLU) was also applied for the synthesis of ethyl valerate. Following 24 h incubation of the immobilized lipase on the selected support in n-hexane and solvent free media, the esterification percentages were 72.9% and 28.9%, respectively. - Graphical abstract: A schematic of the preparation of PEI- and succinated PEI-grafted Fe{sub 3}O{sub 4} MNPs (MNPs@PEI) and the immobilization of lipase by covalent bonding and adsorption. - Highlights: • Functionalized polyethylenimine-grafted magnetic nanoparticles were synthesized. • The prepared supports were fully characterized by various analysis methods. • Lipase was immobilized on the nanostructures by adsorption and covalent attachment. • Immobilized lipase produced ethyl valerate in solvent free medium.

Application of a sensitive collection heuristic for very large protein families: Evolutionary relationship between adipose triglyceride lipase (ATGL and classic mammalian lipases

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Berezovsky Igor

2006-03-01

Full Text Available Abstract Background Manually finding subtle yet statistically significant links to distantly related homologues becomes practically impossible for very populated protein families due to the sheer number of similarity searches to be invoked and analyzed. The unclear evolutionary relationship between classical mammalian lipases and the recently discovered human adipose triglyceride lipase (ATGL; a patatin family member is an exemplary case for such a problem. Results We describe an unsupervised, sensitive sequence segment collection heuristic suitable for assembling very large protein families. It is based on fan-like expanding, iterative database searches. To prevent inclusion of unrelated hits, additional criteria are introduced: minimal alignment length and overlap with starting sequence segments, finding starting sequences in reciprocal searches, automated filtering for compositional bias and repetitive patterns. This heuristic was implemented as FAMILYSEARCHER in the ANNIE sequence analysis environment and applied to search for protein links between the classical lipase family and the patatin-like group. Conclusion The FAMILYSEARCHER is an efficient tool for tracing distant evolutionary relationships involving large protein families. Although classical lipases and ATGL have no obvious sequence similarity and differ with regard to fold and catalytic mechanism, homology links detected with FAMILYSEARCHER show that they are evolutionarily related. The conserved sequence parts can be narrowed down to an ancestral core module consisting of three β-strands, one α-helix and a turn containing the typical nucleophilic serine. Moreover, this ancestral module also appears in numerous enzymes with various substrate specificities, but that critically rely on nucleophilic attack mechanisms.

Autoradiographic imaging of cerebral ischemia using hypoxic marker: Tc-99m-HL91 in animal models

International Nuclear Information System (INIS)

Jiang, N.Y.; Zhu, C.S.; Hu, X.K.

2002-01-01

Objective: To explore the possibility of Tc-99m-HL91 imaging in detecting the ischemic penumbra during acute stoke. Methods: 16 Sprague-Dawley (SD) rats were divided into operation group (n=12) and pseudo-operation group (n=4) randomly. In operation group, 12 middle cerebral artery occlusion animal (MCAO) models were established by electrocautery. 4 rats in pseudo-operation group were treated as a control without occlusion. All animals were injected Tc-99m-HL91 intravenously 2 hours after occlusion. Animals were killed at different time after injection and brains were removed rapidly from the skull to do the autoradiographic study. Result: The ischemic territory accumulated more Tc-99m-HL91 than the opposite site in the autoradiogram at 1 hour after injection. The ischemic cerebral tissue can be visualized clearly. At 2, 4 hours after injection, the difference of accumulation of Tc-99m-HL91 in target and non-target site became more obvious. By using computer-enhanced imaging analysis, the optical density (OD) ratio differences between each subgroup of operation group and pseudo-operation group were all significant. Conclusion : Tc-99m-HL91 can be avidly taken up by ischemic penumbra. Tc-99m-HL91 is a potential agent for imaging hypoxic tissue, and Tc-99m-HL91 SPECT may be a promising imaging method in detecting the ischemic penumbra

Autoradiographic imaging of cerebral ischaemia using hypoxic marker: 99mTc-HL91 in animal models

International Nuclear Information System (INIS)

Ningyi, J.; Cansheng, Z.; Xiaoke, H.

2002-01-01

Objective: To explore the possibility of 99mTc-HL91 imaging in detecting the ischemic penumbra during acute stoke. Methods 16 Sprague-Dawley (SD) rats were divided into operation group (n=12) and pseudo-operation group (n=4) randomly. In operation group, 12 middle cerebral artery occlusion animal (MCAO) models were established by electrocautery. 4 rats in pseudo-operation group were treated as a control without occlusion. All animals were injected 99mTc-HL91 intravenously 2 hours after occlusion. Animals were killed at different time after injection and brains were removed rapidly from the skull to do the autoradiographic study. Result The ischemic territory accumulated more 99mTc-HL91 than the opposite site in the autoradiogram at 1 hour after injection. The ischemic cerebral tissue can be visualized clearly. At 2, 4 hours after injection, the difference of accumulation of 99mTc-HL91 in target and non-target site became more obvious. By using computer-enhanced imaging analysis, the optical density (OD) ratio differences between each subgroup of operation group and pseudo-operation group were all significant. Conclusion 99mTc-HL91 can be avidly taken up by ischemic penumbra. 99mTc-HL91 is a potential agent for imaging hypoxic tissue, and 99mTc-HL91 SPECT may be a promising imaging method in detecting the ischemic penumbra

Coconut oil induced production of a surfactant-compatible lipase from Aspergillus tamarii under submerged fermentation.

Science.gov (United States)

Das, Arijit; Bhattacharya, Sourav; Shivakumar, Srividya; Shakya, Sujina; Sogane, Swathi Shankar

2017-02-01

Filamentous fungi are efficient producers of lipases. The present study focuses on identification of a potent lipolytic fungus and enhancement of lipase production through optimization of nutritional and cultural conditions under submerged fermentation. Molecular characterization of the fungus by 18S rDNA sequencing revealed its identity as Aspergillus tamarii with 98% homology. Maximum lipase production was noted in mineral salts medium supplemented with coconut oil (2.5%, v/v). A combination of ammonium chloride (2%, w/v) and tryptone (2%, w/v) facilitated maximum lipase production at pH 5 of the production medium. A carbon: nitrogen ratio of 1:4 led to significant (p oil stain removal activity of a commercially available detergent by 2.2-fold. The current findings suggest the potentiality of this fungal lipase to be used in detergent formulation. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Immobilization of Beauveria bassiana Lipase on Silica Gel by Physical Adsorption

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Vanessa Hitomi Sugahara

2014-12-01

Full Text Available Extracellular lipase from Beauveria bassianastrain CG481 was immobilized by using thirteen different immobilization protocols. Silica gel was chosen as the most suitable adsorbent with 94.8% of activity yield. The adsorption on silica gel did not change the optimum pH (8.5 and temperature (45ºC values of the free lipase (FL for lipolytic activity, and it showed higher activities in extreme conditions (pH 9.0 to 10.5, 60ºC. The lipase immobilized on silica gel (ILS showed enhanced stability at pH 7.0 after 120 h incubation (69.0% when compared to FL (33.3%. The thermal stability was also enhanced by immobilization at 60ºC in aqueous (64.6% and organic medium (95.1%, while FL showed only 40.6% of residual activity in aqueous medium and exhibited no activity for esterification reaction in n-heptane. The treatment of ILS with 0.8 M NaCl prevented lipase desorption while Triton X-100 (0.1% resulted the enzyme leakage. The ILS was reused for four times for esterification reaction with 80.8% of initial activity.

Medicinal Plants and Their Inhibitory Activities against Pancreatic Lipase: A Review

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Atefehalsadat Seyedan

2015-01-01

Full Text Available Obesity is recognized as a major life style disorder especially in developing countries and it is prevailing at an alarming speed in new world countries due to fast food intake, industrialization, and reduction of physical activity. Furthermore, it is associated with a vast number of chronic diseases and disabilities. To date, relatively effective drugs, from either natural or synthetic sources, are generally associated with serious side effects, often leading to cessation of clinical trials or even withdrawal from the market. In order to find new compounds which are more effective or with less adverse effects compared to orlistat, the drug that has been approved for obesity, new compounds isolated from natural products are being identified and screened for antiobesity effects, in particular, for their pancreatic lipase inhibitory effect. Pancreatic lipase inhibitory activity has been extensively used for the determination of potential efficacy of natural products as antiobesity agents. In attempts to identify natural products for overcoming obesity, more researches have been focused on the identification of newer pancreatic lipase inhibitors with less unpleasant adverse effects. In this review, we consider the potential role of plants that have been investigated for their pancreatic lipase inhibitory activity.

Production of extracellular lipases by Rhizopus oligosporus in a stirred fermentor

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Tehreema Iftikhar

2010-12-01

Full Text Available The present investigation deals with the kinetics of submerged extracellular lipases fermentation by both wild and mutant strains of Rhizopus oligosporus var. microsporus in a laboratory scale stirred fermentor. Other parameters studied were inoculum size, pH, agitation and rate of aeration. It was found that the growth and lipases production was increased gradually and reached its maximum 9.07± 0.42ª U mL-1 (W and 42.49 ± 3.91ª U mL-1 (M after 30h of fermentation for both wild and mutant strain. There is overall increase of 109% (W and 124% (M in the production of extracellular lipases as compared to shake flask. Another significant finding of the present study is that the fermentation period is reduced to 30 h in case of wild and 23 h in case of mutant from 48 h in shake flask studies. The specific productivity of mutant strain (qp = 377.3 U/g cells/h was several folds higher than wild strain. The specific production rate and growth coefficient revealed the hyperproducibility of extracellular lipases using mutant IIB-63NTG-7.

Immobilization of lipase and keratinase on functionalized SBA-15 nanostructured materials

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Le, Hy G.; Vu, Tuan A.; Tran, Hoa T. K.; Dang, Phuong T.

2013-12-01

SBA-15 nanostructured materials were synthesized via hydrothermal treatment and were functionalized with 3- aminopropyltriethoxysilane (APTES). The obtained samples were characterized by different techniques such as XRD, BET, TEM, IR and DTA. After functionalization, it showed that these nanostrucrured materials still maintained the hexagonal pore structure of the parent SBA-15. The model enzyms chosen in this study were lipase and keratinase. Lipase was a biocatalyst for hydrolyzation of long chain triglycerides or methyl esters of long chain alcohols and fatty acids; keratinase is a proteolytic enzyme that catalyzes the cleavage of keratin. The functionalized SBA-15 materials were used to immobilize lipase and keratinase, exhibiting higher activity than that of the unfunctionalized pure silica SBA-15 ones. This might be due to the enhancing of surface hydrophobicity upon functionalization. The surface functionalization of the nanostructured silicas with organic groups can favor the interaction between enzyme and the supports and consequently increasing the operational stability of the immobilized enzymes. The loading of lipase on functionalized SBA-15 materials was higher than that of keratinase. This might be rationalized by the difference in size of enzyms.

Isolation and characterization of novel lipases/esterases from a bovine rumen metagenome.

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Privé, Florence; Newbold, C Jamie; Kaderbhai, Naheed N; Girdwood, Susan G; Golyshina, Olga V; Golyshin, Peter N; Scollan, Nigel D; Huws, Sharon A

2015-07-01

Improving the health beneficial fatty acid content of meat and milk is a major challenge requiring an increased understanding of rumen lipid metabolism. In this study, we isolated and characterized rumen bacterial lipases/esterases using functional metagenomics. Metagenomic libraries were constructed from DNA extracted from strained rumen fluid (SRF), solid-attached bacteria (SAB) and liquid-associated rumen bacteria (LAB), ligated into a fosmid vector and subsequently transformed into an Escherichia coli host. Fosmid libraries consisted of 7,744; 8,448; and 7,680 clones with an average insert size of 30 to 35 kbp for SRF, SAB and LAB, respectively. Transformants were screened on spirit blue agar plates containing tributyrin for lipase/esterase activity. Five SAB and four LAB clones exhibited lipolytic activity, and no positive clones were found in the SRF library. Fosmids from positive clones were pyrosequenced and twelve putative lipase/esterase genes and two phospholipase genes retrieved. Although the derived proteins clustered into diverse esterase and lipase families, a degree of novelty was seen, with homology ranging from 40 to 78% following BlastP searches. Isolated lipases/esterases exhibited activity against mostly short- to medium-chain substrates across a range of temperatures and pH. The function of these novel enzymes recovered in ruminal metabolism needs further investigation, alongside their potential industrial uses.

Screening Brazilian Macrophomina phaseolina isolates for alkaline lipases and other extracellular hydrolases.

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Schinke, Claudia; Germani, José C

2012-03-01

Macrophomina phaseolina, phylum Ascomycota, is a phytopathogenic fungus distributed worldwide in hot dry areas. There are few studies on its secreted lipases and none on its colony radial growth rate, an indicator of fungal ability to use nutrients for growth, on media other than potato-dextrose agar. In this study, 13 M. phaseolina isolates collected in different Brazilian regions were screened for fast-growth and the production of hydrolases of industrial interest, especially alkaline lipases. Hydrolase detection and growth rate determination were done on citric pectin, gelatin, casein, soluble starch, and olive oil as substrates. Ten isolates were found to be active on all substrates tested. The most commonly detected enzymes were pectinases, amylases, and lipases. The growth rate on pectin was significantly higher (P media identified CMM 2105, CMM 1091, and PEL as the fastest-growing isolates. The lipase activity of four isolates grown on olive oil was followed for 4 days by measuring the activity in the cultivation broth. The specific lipolytic activity of isolate PEL was significantly higher at 96 h (130 mU mg protein(-1)). The broth was active at 37 °C, pH 8, indicating the potential utility of the lipases of this isolate in mild alkaline detergents. There was a strong and positive correlation (0.86) between radial growth rate and specific lipolytic activity.

Efficient utilization of xylanase and lipase producing thermophilic ...

African Journals Online (AJOL)

Efficient utilization of xylanase and lipase producing thermophilic marine actinomycetes ( Streptomyces albus and Streptomyces hygroscopicus ) in the production of ecofriendly alternative energy from waste.

Evaluation of a novel thermo-alkaline Staphylococcus aureus lipase for application in detergent formulations

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Abir Ben Bacha

2018-03-01

Full Text Available An extracellular lipase of a newly isolated S. aureus strain ALA1 (SAL4 was purified from the optimized culture medium. The SAL4 specific activity determined at 60 °C and pH 12 by using olive oil emulsion or TC4, reached 7215 U/mg and 2484 U/mg, respectively. The 38 NH2-terminal amino acid sequence of the purified enzyme starting with two extra amino acid residues (LK was similar to known staphylococcal lipase sequences. This novel lipase maintained almost 100% and 75% of its full activity in a pH range of 4.0–12 after a 24 h incubation or after 0.5 h treatment at 70 °C, respectively. Interestingly, SAL4 displayed appreciable stability toward oxidizing agents, anionic and non-ionic surfactants in addition to its compatibility with several commercial detergents. Overall, these interesting characteristics make this new lipase promising for its application in detergent industry. Keywords: Staphylococcus aureus lipase, Purification, Characterization, Thermo-alkaline, Detergent-stable

HL-1 tokamak data acquisition system and its initial application in the physical experiment

International Nuclear Information System (INIS)

Deng Huichen; Fu Bo; Dong Jiafu

1989-11-01

A HL-1 tokamak data acquisition system has been developed and has been used in the physical experiment. The hardware and software configuration of the system, as well as the typical acquired data in the HL-1 experiment are introduced

The CMS Tracker upgrade for HL-LHC

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Ahuja, Sudha

2017-01-01

The LHC machine is planning an upgrade program which will smoothly bring the luminosity to about 5 $\\times$ $10^{34} $cm$^{-2}$s$^{-1}$ in 2028, to possibly reach an integrated luminosity of 3000 fb$^{-1}$ by the end of 2037. This High Luminosity LHC scenario, HL-LHC, will require a preparation program of the LHC detectors known as Phase-2 upgrade. The current CMS Outer Tracker, already running beyond design specifications, and CMS Phase1 Pixel Detector will not be able to survive HL-LHC radiation conditions and CMS will need completely new devices, in order to fully exploit the high-demanding operating conditions and the delivered luminosity. The new Outer Tracker should have also trigger capabilities. To achieve such goals, R$\\&$D activities are ongoing to explore options both for the Outer Tracker, and for the pixel Inner Tracker. Solutions are being developed that would allow including tracking information at Level-1. The design choices for the Tracker upgrades are discussed along with some highlights...

Lipase production by solid-state fermentation in fixed-bed bioreactors

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Elisa d'Avila Costa Cavalcanti

2005-06-01

Full Text Available In the present work, packed bed bioreactors were employed with the aim of increasing productivity and scaling up of lipase production using Penicillium simplicissimum in solid-state fermentation. The influence of temperature and air flow rate on enzyme production was evaluated employing statistical experimental design, and an empirical model was adjusted to the experimental data. It was shown that higher lipase activities could be achieved at lower temperatures and higher air flow rates. The maximum lipase activity (26.4 U/g was obtained at the temperature of 27°C and air flow rate of 0.8 L/min.O fungo Penicillium simplicissimum se mostrou, em trabalhos anteriores, um ótimo produtor de lipase por fermentação no estado sólido, quando cultivado em biorreatores do tipo bandeja, utilizando a torta de babaçu como meio de cultura. Com o objetivo de aumentar a produtividade e possibilitar uma ampliação de escala, foi investigado, no presente trabalho, o emprego de biorreatores de leito fixo com aeração forçada. Os biorreatores utilizados tinham 4 cm de diâmetro interno e 14 cm de altura útil. Empregando-se planejamento estatístico de experimentos como ferramenta, foram avaliadas as influências da temperatura e da vazão de ar sobre a produção de lipase nestes biorreatores. Os resultados obtidos permitiram ajustar um modelo empírico, o qual indicou que maiores atividades lipásicas são alcançadas para temperaturas mais baixas e vazões de ar mais altas. A atividade lipásica máxima (26,4 U/g foi obtida para temperatura de 27°C e vazão de ar de 0,8 L/min.

Serum amylase and lipase activities after exploratory laparotomy in dogs.

Science.gov (United States)

Bellah, J R; Bell, G

1989-09-01

Serum amylase and lipase activities and creatinine concentration were determined before surgery, and at 1 and 2 days after exploratory laparotomy in 24 dogs. Examination of all viscera was done during each laparotomy, but a surgical procedure was not performed. The mean serum activities for lipase were: before surgery, 0.71 (0.0 to 2.0) Cherry Crandall units (CCU)/L; 1 day after surgery, 2.1 (0.0 to 4.5) CCU/L; and 2 days after surgery, 1.19 (0.0 to 3.9) CCU/L. The mean serum activities for amylase were: before surgery, 1,958 (1,027 to 3,426) IU/L; 1 day after surgery, 1,538 (937 to 2,659) IU/L; and 2 days after surgery, 1,663 (1,066 to 2,274) IU/L. Serum creatinine concentrations before surgery, 1 day after surgery, and 2 days after surgery were 0.88 (0.2 to 1.7) mg/dl, 0.78 (0.4 to 1.3) mg/dl, and 0.78 (0.3 to 1.3) mg/dl, respectively. Mean preoperative, day-1, and day-2 serum amylase activities and serum creatinine concentrations did not differ significantly from each other. Mean preoperative and day-2 serum lipase activities did not differ significantly; however, mean serum lipase activity was significantly greater when day 1 activities were compared with preoperative activities (P = 0.0002). Post-mortem examinations revealed no gross or histologic evidence of pancreatitis in any dog. The results of this study show that a 3 or more fold increase in serum lipase activity may occur after routine exploratory laparotomy in dogs without clinical signs or gross evidence of pancreatitis. Histologic evidence of pancreatitis was not found in the right pancreatic lobes in any dog.

Design for effective development and prototyping of the HL-20

Science.gov (United States)

Urie, David M.; Floreck, Paul A.; McMorris, John A.; Elvin, John D.

1993-10-01

A feasibility study of the HL-20 personnel launch system (PLS) concept was conducted by a team which focused on creating a PLS design approach and an accelerated development plan consistent with the historical 'Skunk Works' approach to rapid prototyping. Technical design, manufacturing, system testing, and operations and support elements of the predefined baseline concept were evaluated. An initial phase program, featuring a concurrent system test during design and development, leading to the orbital flight of an unmanned HL-20 prototype on a Titan III launch system, was prescribed. A second-phase development and manufacturing plan leading to system operational status was also formulated. Baseline design feature modifications were made when necessary, without compromise to performance, to satisfy the prototype development plan. Technical design details and off-the-shelf hardware candidates were also identified for several subsystems, including the launch-system interface adapter/emergency escape system. The technical feasibility of the system and applicability of the Skunk Works approach to development of the HL-20/PLS were verified.

PRELIMINARY STUDIES FOR PRODUCING CRUDE LIPASE FROM TEMPE’S MOULD CULTIVATED IN RICE-HUSK-BASED SOLID MEDIA

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Teuku Beuna Bardant

2010-06-01

Full Text Available The goal of these preliminary studies is to support Indonesian program for increasing palm oil added value through independent production technology based on Indonesian natural resources. Various palm oil derivatives could be synthesized enzymatically using lipase from microbes that available in Indonesia. Tempe's mould is available in abundance in Indonesia and had already been proved for producing lipase. This paper provides information about producing crude lipase from Tempe's mould cultivated in rice-husk-based solid media using palm oil as carbon source. Observed variables include solid media composition, optimum fermentation time, extraction and enriching process of crude lipase. The crude lipase was analyzed its hydrolysis activity on coconut oil and palm oil. The result of these preliminary studies shows that this production process is a simple and tough process and very potential to be developed.   Keywords: lipase, Tempe's mould, palm oil, solid fermentation, rice husk

Dynamical Stability of Imaged Planetary Systems in Formation: Application to HL Tau

Science.gov (United States)

Tamayo, D.; Triaud, A. H. M. J.; Menou, K.; Rein, H.

2015-06-01

A recent Atacama Large Millimeter/Submillimeter Array image revealed several concentric gaps in the protoplanetary disk surrounding the young star HL Tau. We consider the hypothesis that these gaps are carved by planets, and present a general framework for understanding the dynamical stability of such systems over typical disk lifetimes, providing estimates for the maximum planetary masses. We collect these easily evaluated constraints into a workflow that can help guide the design and interpretation of new observational campaigns and numerical simulations of gap opening in such systems. We argue that the locations of resonances should be significantly shifted in massive disks like HL Tau, and that theoretical uncertainties in the exact offset, together with observational errors, imply a large uncertainty in the dynamical state and stability in such disks. This presents an important barrier to using systems like HL Tau as a proxy for the initial conditions following planet formation. An important observational avenue to breaking this degeneracy is to search for eccentric gaps, which could implicate resonantly interacting planets. Unfortunately, massive disks like HL Tau should induce swift pericenter precession that would smear out any such eccentric features of planetary origin. This motivates pushing toward more typical, less massive disks. For a nominal non-resonant model of the HL Tau system with five planets, we find a maximum mass for the outer three bodies of approximately 2 Neptune masses. In a resonant configuration, these planets can reach at least the mass of Saturn. The inner two planets’ masses are unconstrained by dynamical stability arguments.

Autoradiographic imaging of cerebral ischemia using hypoxic marker: 99mTc-HL91 in animal models

International Nuclear Information System (INIS)

Zhu Cansheng; Jiang Ningyi; Hu Xiaoke

2001-01-01

Objective: To explore the possibility of 99m Tc-HL91 imaging in detecting the ischemic penumbra during acute stoke. Methods; 16 Sprague-Dawley (SD) rats were divided into operation group (n=12) and pseudo-operation group (n=4) randomly. In operation group, 12 middle cerebral artery occlusion animal (MCAO) models were established by electrocautery. 4 rats in pseudo-operation group were treated as a control without occlusion. All animals were injected 99m Tc-HL91 intravenously 2 hours after occlusion. Animals were killed at different time after injection and brains were removed rapidly from the skull to do the autoradiographic study. Results: The ischemic territory accumulated more 99m Tc-HL91 than the opposite site in the autoradiogram at 1 hour after injection. The ischemic cerebral tissue can be visualized clearly. At 2, 4 hours after injection, the difference of accumulation of 99m Tc-HL91 in target and non-target site became more obvious. By using computer-enhanced imaging analysis, the optical density (OD) ratio differences between each subgroup of operation group and pseudo-operation group were all significant. The OD ratios (T/N) were 1.2691±0.0189, 1.3542±0.0119, 2.1201±0.0616, 2.5369±0.1214 respectively at 1, 2, 4 hours after 99m Tc-HL91 injection. Conclusion: 99m Tc-HL91 can be avidly taken up by ischemic penumbra. 99m Tc-HL91 is a potential agent for imaging hypoxic tissue, and 99m Tc-HL91 SPECT may be a promising imaging method in detecting the ischemic penumbra

Production of structured lipids in a packed-bed reactor with Thermomyces lanuginosa lipase

DEFF Research Database (Denmark)

Xu, Xuebing; Porsgaard, Trine; Zhang, Hong

2002-01-01

Lipase-catalyzed interesterification between fish oil and medium-chain TAG has been investigated in a packed-bed reactor with a commercially immobilized enzyme. The enzyme, a Thermomyces lanuginosa lipase immobilized on silica by granulation (Lipozyme TL IM; Novozymes A/S, Bagsvaerd, Denmark), ha...

Production of Thermoalkaliphilic Lipase from Geobacillus thermoleovorans DA2 and Application in Leather Industry.

Science.gov (United States)

Abol Fotouh, Deyaa M; Bayoumi, Reda A; Hassan, Mohamed A

2016-01-01

Thermophilic and alkaliphilic lipases are meeting a growing global attention as their increased importance in several industrial fields. Over 23 bacterial strains, novel strain with high lipolytic activity was isolated from Southern Sinai, Egypt, and it was identified as Geobacillus thermoleovorans DA2 using 16S rRNA as well as morphological and biochemical features. The lipase was produced in presence of fatty restaurant wastes as an inducing substrate. The optimized conditions for lipase production were recorded to be temperature 60°C, pH 10, and incubation time for 48 hrs. Enzymatic production increased when the organism was grown in a medium containing galactose as carbon source and ammonium phosphate as nitrogen source at concentrations of 1 and 0.5% (w/v), respectively. Moreover, the optimum conditions for lipase production such as substrate concentration, inoculum size, and agitation rate were found to be 10% (w/v), 4% (v/v), and 120 rpm, respectively. The TA lipase with Triton X-100 had the best degreasing agent by lowering the total lipid content to 2.6% as compared to kerosene (7.5%) or the sole crude enzyme (8.9%). It can be concluded that the chemical leather process can be substituted with TA lipase for boosting the quality of leather and reducing the environmental hazards.

Production of Thermoalkaliphilic Lipase from Geobacillus thermoleovorans DA2 and Application in Leather Industry

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Deyaa M. Abol Fotouh

2016-01-01

Full Text Available Thermophilic and alkaliphilic lipases are meeting a growing global attention as their increased importance in several industrial fields. Over 23 bacterial strains, novel strain with high lipolytic activity was isolated from Southern Sinai, Egypt, and it was identified as Geobacillus thermoleovorans DA2 using 16S rRNA as well as morphological and biochemical features. The lipase was produced in presence of fatty restaurant wastes as an inducing substrate. The optimized conditions for lipase production were recorded to be temperature 60°C, pH 10, and incubation time for 48 hrs. Enzymatic production increased when the organism was grown in a medium containing galactose as carbon source and ammonium phosphate as nitrogen source at concentrations of 1 and 0.5% (w/v, respectively. Moreover, the optimum conditions for lipase production such as substrate concentration, inoculum size, and agitation rate were found to be 10% (w/v, 4% (v/v, and 120 rpm, respectively. The TA lipase with Triton X-100 had the best degreasing agent by lowering the total lipid content to 2.6% as compared to kerosene (7.5% or the sole crude enzyme (8.9%. It can be concluded that the chemical leather process can be substituted with TA lipase for boosting the quality of leather and reducing the environmental hazards.

In vivo functional expression of a screened P. aeruginosa chaperone-dependent lipase in E. coli

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Wu Xiangping

2012-09-01

Full Text Available Abstract Background Microbial lipases particularly Pseudomonas lipases are widely used for biotechnological applications. It is a meaningful work to design experiments to obtain high-level active lipase. There is a limiting factor for functional overexpression of the Pseudomonas lipase that a chaperone is necessary for effective folding. As previously reported, several methods had been used to resolve the problem. In this work, the lipase (LipA and its chaperone (LipB from a screened strain named AB which belongs to Pseudomonas aeruginosa were overexpressed in E. coli with two dual expression plasmid systems to enhance the production of the active lipase LipA without in vitro refolding process. Results In this work, we screened a lipase-produced strain named AB through the screening procedure, which was identified as P. aeruginosa on the basis of 16S rDNA. Genomic DNA obtained from the strain was used to isolate the gene lipA (936 bp and lipase specific foldase gene lipB (1023 bp. One single expression plasmid system E. coli BL21/pET28a-lipAB and two dual expression plasmid systems E. coli BL21/pETDuet-lipA-lipB and E. coli BL21/pACYCDuet-lipA-lipB were successfully constructed. The lipase activities of the three expression systems were compared to choose the optimal expression method. Under the same cultured condition, the activities of the lipases expressed by E. coli BL21/pET28a-lipAB and E. coli BL21/pETDuet-lipA-lipB were 1300 U/L and 3200 U/L, respectively, while the activity of the lipase expressed by E. coli BL21/pACYCDuet-lipA-lipB was up to 8500 U/L. The lipase LipA had an optimal temperature of 30°C and an optimal pH of 9 with a strong pH tolerance. The active LipA could catalyze the reaction between fatty alcohols and fatty acids to generate fatty acid alkyl esters, which meant that LipA was able to catalyze esterification reaction. The most suitable fatty acid and alcohol substrates for esterification were octylic acid and hexanol

Pseudomonas sp. BUP6 produces a thermotolerant alkaline lipase with trans-esterification efficiency in producing biodiesel.

Science.gov (United States)

Priji, Prakasan; Sajith, Sreedharan; Faisal, Panichikkal Abdul; Benjamin, Sailas

2017-12-01

The present study describes the characteristics of a thermotolerant and alkaline lipase secreted by Pseudomonas sp. BUP6, a novel rumen bacterium isolated from Malabari goat, and its trans -esterification efficiency in producing biodiesel from used cooking oil (UCO). The extracellular lipase was purified to homogeneity (35.8 times purified with 14.8% yield) employing (NH 4 ) 2 SO 4 salt precipitation and Sephadex G-100 chromatography. The apparent molecular weight of this lipase on SDS-PAGE was 35 kDa, the identity of which was further confirmed by MALDI-TOF/MS. The purified lipase was found stable at a pH range of 7-9 with the maximum activity (707 U/ml) at pH 8.2; and was active at the temperature ranging from 35 to 50 °C with the optimum at 45 °C (891 U/ml). Triton X-100 and EDTA had no effect on the activity of lipase; whereas SDS, Tween-80 and β-mercaptoethanol inhibited its activity significantly. Moreover, Ca 2+ (1.0 mM) enhanced the activity of lipase (1428 U/ml) by 206% vis-à-vis initial activity; while Zn 2+ , Fe 2+ and Cu 2+ decreased the activity significantly. Using para -nitrophenyl palmitate as substrate, the K m (11.6 mM) and V max [668.9 μmol/(min/mg)] of the purified lipase were also determined. Crude lipase was used for analyzing its trans -esterification efficiency with used cooking oil and methanol which resulted in the worthy yield of fatty acid methyl esters, FAME (45%) at 37 °C, indicating its prospects in biodiesel industry. Thus, the lipase secreted by the rumen bacterium, Pseudomonas sp. BUP6, offers great potentials to be used in various industries including the production of biodiesel by trans -esterification.

Differential effects of low-fat and high-fat diets on fed-state hepatic triacylglycerol secretion, hepatic fatty acid profiles, and DGAT-1 protein expression in obese-prone Sprague–Dawley rats

Science.gov (United States)

Heden, Timothy D.; Morris, E. Matthew; Kearney, Monica L.; Liu, Tzu-Wen; Park, Young-min; Kanaley, Jill A.; Thyfault, John P.

2015-01-01

The purpose of this study was to compare the effects of short-term low-fat (LF) and high-fat (HF) diets on fed-state hepatic triacylglycerol (TAG) secretion, the content of proteins involved in TAG assembly and secretion, fatty acid oxidation (FAO), and the fatty acid profile of stored TAG. Using selectively bred obese-prone Sprague–Dawley rats, we directly measured fed-state hepatic TAG secretion, using Tyloxapol (a lipoprotein lipase inhibitor) and a standardized oral mixed meal (45% carbohydrate, 40% fat, 15% protein) bolus in animals fed a HF or LF diet for 2 weeks, after which the rats were maintained on their respective diet for 1 week (washout) prior to the liver being excised to measure protein content, FAO, and TAG fatty acid profiles. Hepatic DGAT-1 protein expression was ~27% lower in HF- than in LF-fed animals (p < 0.05); the protein expression of all other molecules was similar in the 2 diets. The fed-state hepatic TAG secretion rate was ~39% lower (p < 0.05) in HF- (4.62 ± 0.18 mmol·h−1) than in LF- (7.60 ± 0.57 mmol·h−1) fed animals. Hepatic TAG content was ~2-fold higher (p < 0.05) in HF- (1.07 ± 0.15 nmol·g−1 tissue) than in LF- (0.50 ± 0.16 nmol·g−1 tissue) fed animals. In addition, the fatty acid profile of liver TAG in HF-fed animals closely resembled the diet, whereas in LF-fed animals, the fatty acid profile consisted of mostly de novo synthesized fatty acids. FAO was not altered by diet. LF and HF diets differentially alter fed-state hepatic TAG secretion, hepatic fatty acid profiles, and DGAT-1 protein expression. PMID:24669989

Differential effects of low-fat and high-fat diets on fed-state hepatic triacylglycerol secretion, hepatic fatty acid profiles, and DGAT-1 protein expression in obese-prone Sprague-Dawley rats.

Science.gov (United States)

Heden, Timothy D; Morris, E Matthew; Kearney, Monica L; Liu, Tzu-Wen; Park, Young-Min; Kanaley, Jill A; Thyfault, John P

2014-04-01

The purpose of this study was to compare the effects of short-term low-fat (LF) and high-fat (HF) diets on fed-state hepatic triacylglycerol (TAG) secretion, the content of proteins involved in TAG assembly and secretion, fatty acid oxidation (FAO), and the fatty acid profile of stored TAG. Using selectively bred obese-prone Sprague-Dawley rats, we directly measured fed-state hepatic TAG secretion, using Tyloxapol (a lipoprotein lipase inhibitor) and a standardized oral mixed meal (45% carbohydrate, 40% fat, 15% protein) bolus in animals fed a HF or LF diet for 2 weeks, after which the rats were maintained on their respective diet for 1 week (washout) prior to the liver being excised to measure protein content, FAO, and TAG fatty acid profiles. Hepatic DGAT-1 protein expression was ∼27% lower in HF- than in LF-fed animals (p < 0.05); the protein expression of all other molecules was similar in the 2 diets. The fed-state hepatic TAG secretion rate was ∼39% lower (p < 0.05) in HF- (4.62 ± 0.18 mmol·h(-1)) than in LF- (7.60 ± 0.57 mmol·h(-1)) fed animals. Hepatic TAG content was ∼2-fold higher (p < 0.05) in HF- (1.07 ± 0.15 nmol·g(-1) tissue) than in LF- (0.50 ± 0.16 nmol·g(-1) tissue) fed animals. In addition, the fatty acid profile of liver TAG in HF-fed animals closely resembled the diet, whereas in LF-fed animals, the fatty acid profile consisted of mostly de novo synthesized fatty acids. FAO was not altered by diet. LF and HF diets differentially alter fed-state hepatic TAG secretion, hepatic fatty acid profiles, and DGAT-1 protein expression.

Ultrasound-Assisted Esterification of Valeric Acid to Alkyl Valerates Promoted by Biosilicified Lipases

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Soledad Cebrián-García

2018-06-01

Full Text Available A novel, environmentally friendly, and sustainable ultrasound-assisted methodology in the valorization of valeric acid to alkyl valerate using a biosilicified lipase from Candida antarctica is reported. This one-pot room temperature methodology of enzyme biosilicification leads to biosilicified lipases with improved activity and reaction efficiency as compared to free enzymes. Yields in the ultrasound-promoted esterification of valeric acid was ca. 90% in 2 h with 15% m/v of biosilicified lipase (Bio-lipase; 616 U/g biocatalyst enzymatic activity and a molar ratio 1:2 (valeric acid:ethanol, slightly superior to that observed by the free enzyme (75% conversion, 583U/g biocatalyst enzymatic activity. The reuse of enzymes in these conditions was tested and the results show a relatively good reusability of these biosilicified enzymes under the investigated conditions, particularly preserving fairly stable specific activities (616 vs. 430 U/g biocatalyst after four reuses.

State of the art and prospective of lipase-catalyzed transesterification reaction for biodiesel production

International Nuclear Information System (INIS)

Amini, Zeynab; Ilham, Zul; Ong, Hwai Chyuan; Mazaheri, Hoora; Chen, Wei-Hsin

2017-01-01

Highlights: • Enzymatic transesterification process is less energy intensive and robust. • Nano-materials are promising immobilization supports for lipase. • Packed-bed reactors are appropriate for scale-up use. • Potential recombinant, whole cell and recombinant whole cell lipases were enlisted. • Genetic engineering is a promising prospect in biodiesel area. - Abstract: The world demand for fuel as energy sources have arisen the need for generating alternatives such as biofuel. Biodiesel is a renewable fuel used particularly in diesel engines. Currently, biodiesel is mainly produced through transesterification reactions catalyzed by chemical catalysts, which produces higher fatty acid alkyl esters in shorter reaction time. Although extensive investigations on enzymatic transesterification by downstream processing were carried out, enzymatic transesterification has yet to be used in scale-up since commercial lipases are chiefly limited to the cost as well as long reaction time. While numerous lipases were studied and proven to have the high catalytic capacity, still enzymatic reaction requires more investigation. To fill this gap, finding optimal conditions for the reaction such as alcohol and oil choice, water content, reaction time and temperature through proper reaction modelling and simulations as well as the appropriate design and use of reactors for large scale production are crucial issues that need to be accurately addressed. Furthermore, lipase concentration, alternative lipase resources through whole cell technology and genetic engineering, recent immobilizing materials including nanoparticles, and the capacity of enzyme to be reused are important criteria to be neatly investigated. The present work reviews the current biodiesel feedstock, catalysis, general and novel immobilizing materials, bioreactors for enzymatic transesterification, potential lipase resources, intensification technics, and process modelling for enzymatic

Lipase biofilm deposited by Matrix Assisted Pulsed Laser Evaporation technique

International Nuclear Information System (INIS)

Aronne, Antonio; Bloisi, Francesco; Calabria, Raffaela; Califano, Valeria; Depero, Laura E.; Fanelli, Esther; Federici, Stefania; Massoli, Patrizio; Vicari, Luciano R.M.

2015-01-01

Highlights: • A lipase film was deposited with Matrix Assisted Pulsed Laser Evaporation technique. • FTIR spectra show that laser irradiation do not damage lipase molecule. • Laser fluence controls the characteristics of complex structure generated by MAPLE. - Abstract: Lipase is an enzyme that finds application in biodiesel production and for detection of esters and triglycerides in biosensors. Matrix Assisted Pulsed Laser Evaporation (MAPLE), a technique derived from Pulsed Laser Deposition (PLD) for deposition of undamaged biomolecules or polymers, is characterized by the use of a frozen target obtained from a solution/suspension of the guest material (to be deposited) in a volatile matrix (solvent). The presence of the solvent avoids or at least reduces the potential damage of guest molecules by laser radiation but only the guest material reaches the substrate in an essentially solvent-free deposition. MAPLE can be used for enzymes immobilization, essential for industrial application, allowing the development of continuous processes, an easier separation of products, the reuse of the catalyst and, in some cases, enhancing enzyme properties (pH, temperature stability, etc.) and catalytic activity in non-aqueous media. Here we show that MAPLE technique can be used to deposit undamaged lipase and that the complex structure (due to droplets generated during extraction from target) of the deposited material can be controlled by changing the laser beam fluence

Lipase biofilm deposited by Matrix Assisted Pulsed Laser Evaporation technique

Energy Technology Data Exchange (ETDEWEB)

Aronne, Antonio [Department of Chemical Engineering, Materials and Industrial Production, University of Naples “Federico II”, Napoli (Italy); Bloisi, Francesco, E-mail: bloisi@na.infn.it [SPIN – CNR, Naples (Italy); Department of Physics, University of Naples “Federico II”, Napoli (Italy); Calabria, Raffaela; Califano, Valeria [Istituto Motori – CNR, Naples (Italy); Depero, Laura E. [Department of Mechanical and Industrial Engineering, University of Brescia, Brescia (Italy); Fanelli, Esther [Department of Chemical Engineering, Materials and Industrial Production, University of Naples “Federico II”, Napoli (Italy); Federici, Stefania [Department of Mechanical and Industrial Engineering, University of Brescia, Brescia (Italy); Massoli, Patrizio [Istituto Motori – CNR, Naples (Italy); Vicari, Luciano R.M. [SPIN – CNR, Naples (Italy); Department of Physics, University of Naples “Federico II”, Napoli (Italy)

2015-05-01

Highlights: • A lipase film was deposited with Matrix Assisted Pulsed Laser Evaporation technique. • FTIR spectra show that laser irradiation do not damage lipase molecule. • Laser fluence controls the characteristics of complex structure generated by MAPLE. - Abstract: Lipase is an enzyme that finds application in biodiesel production and for detection of esters and triglycerides in biosensors. Matrix Assisted Pulsed Laser Evaporation (MAPLE), a technique derived from Pulsed Laser Deposition (PLD) for deposition of undamaged biomolecules or polymers, is characterized by the use of a frozen target obtained from a solution/suspension of the guest material (to be deposited) in a volatile matrix (solvent). The presence of the solvent avoids or at least reduces the potential damage of guest molecules by laser radiation but only the guest material reaches the substrate in an essentially solvent-free deposition. MAPLE can be used for enzymes immobilization, essential for industrial application, allowing the development of continuous processes, an easier separation of products, the reuse of the catalyst and, in some cases, enhancing enzyme properties (pH, temperature stability, etc.) and catalytic activity in non-aqueous media. Here we show that MAPLE technique can be used to deposit undamaged lipase and that the complex structure (due to droplets generated during extraction from target) of the deposited material can be controlled by changing the laser beam fluence.

A simplified method for active-site titration of lipases immobilised on hydrophobic supports.

Science.gov (United States)

Nalder, Tim D; Kurtovic, Ivan; Barrow, Colin J; Marshall, Susan N

2018-06-01

The aim of this work was to develop a simple and accurate protocol to measure the functional active site concentration of lipases immobilised on highly hydrophobic supports. We used the potent lipase inhibitor methyl 4-methylumbelliferyl hexylphosphonate to titrate the active sites of Candida rugosa lipase (CrL) bound to three highly hydrophobic supports: octadecyl methacrylate (C18), divinylbenzene crosslinked methacrylate (DVB) and styrene. The method uses correction curves to take into account the binding of the fluorophore (4-methylumbelliferone, 4-MU) by the support materials. We showed that the uptake of the detection agent by the three supports is not linear relative to the weight of the resin, and that the uptake occurs in an equilibrium that is independent of the total fluorophore concentration. Furthermore, the percentage of bound fluorophore varied among the supports, with 50 mg of C18 and styrene resins binding approximately 64 and 94%, respectively. When the uptake of 4-MU was calculated and corrected for, the total 4-MU released via inhibition (i.e. the concentration of functional lipase active sites) could be determined via a linear relationship between immobilised lipase weight and total inhibition. It was found that the functional active site concentration of immobilised CrL varied greatly among different hydrophobic supports, with 56% for C18, compared with 14% for DVB. The described method is a simple and robust approach to measuring functional active site concentration in immobilised lipase samples. Copyright © 2018 Elsevier Inc. All rights reserved.

Formal methods impact on ANSI standard HL7/IM: filling gaps in MSC theory

NARCIS (Netherlands)

W. Wesselink; N. Goga (Nicolae); A.J. Mooij (Arjan); R. Spronk

2005-01-01

htmlabstractHealth level seven (HL7) is an ANSI standard that provides a comprehensive framework for electronic health information. The most-widely used HL7 specification is called infrastructure management, which facilitates health-care applications to exchange key sets of clinical and

Evaluation of inorganic matrixes as supports for immobilization of microbial lipase

Directory of Open Access Journals (Sweden)

Castro H.F.

2000-01-01

Full Text Available Candida rugosa was immobilized by physical adsorption on several inorganic supports using hexane as coupling medium. The enzymatic activities of the different derivatives were determined by both hydrolysis of olive oil and esterification of n-butanol with butyric acid. The results were compared to previous data obtained by using a controlled porous silica matrix. The goal was to contribute in searching inexpensive supports for optimum lipase performance. All supports examined exhibited good properties for binding the enzyme lipase. Zirconium phosphate was the best support, giving the highest percentage of protein fixation (86% and the highest retention of lipase activity after immobilization (34%. The operational stability performance for niobium oxide derivative was improved by previously activated the support with silane and glutaraldehyde. Thermal stabilities were also examined by thermal gravimetric analysis (TG.

Commissioning and preliminary operation of HL-2A tokamak

International Nuclear Information System (INIS)

Liu Dequan; Liu Yong; Yan Jianchen; Cao Zeng; Yang Qingwei; Zhou Caipin; Li Xiaodong

2005-01-01

HL-2A is a divertor tokamak located at new site of Southwestern Institute of Physics (SWIP), Chengdu, China. It can be operated in double-null and single-null divertor with closed configurations. The effects of the divertor on impurity behaviors, MHD instabilities, transport, wall conditioning and divertor physics are key issues to be studied during the first step operation on HL-2A. Preliminary experiments with limiter and single null divertor configurations were carried out in 2003. Main parameters achieved are the plasma current 168 KA, duration time of 920 ms and plasma linear-averaged density of 1.7 x 10 19 m -3 . The impurities, especially of low Z, are clearly decreased during the divertor experiments

Simultaneous production of lipases and biosurfactants by submerged and solid-state bioprocesses.

Science.gov (United States)

Colla, Luciane Maria; Rizzardi, Juliana; Pinto, Marta Heidtmann; Reinehr, Christian Oliveira; Bertolin, Telma Elita; Costa, Jorge Alberto Vieira

2010-11-01

Lipases and biosurfactants are compounds produced by microorganisms generally involved in the metabolization of oil substrates. However, the relationship between the production of lipases and biosurfactants has not been established yet. Therefore, this study aimed to evaluate the correlation between production of lipases and biosurfactants by submerged (SmgB) and solid-state bioprocess (SSB) using Aspergillus spp., which were isolated from a soil contaminated by diesel oil. SSB had the highest production of lipases, with lipolytic activities of 25.22U, while SmgB had 4.52U. The production of biosurfactants was not observed in the SSB. In the SmgB, correlation coefficients of 91% and 87% were obtained between lipolytic activity and oil in water and water in oil emulsifying activities, respectively. A correlation of 84% was obtained between lipolytic activity and reduction of surface tension in the culture medium. The surface tension decreased from 50 to 28mNm(-1) indicating that biosurfactants were produced in the culture medium. Copyright 2010 Elsevier Ltd. All rights reserved.

Production of lipase from Geotrichum sp and adsorption studies on affinity resin

Directory of Open Access Journals (Sweden)

E. S. KAMIMURA

1999-06-01

Full Text Available There is a growing interest in microbial lipase production due to its great potential for industrial applications such as food additives, industrial reagents and stain removers, as well as for medical applications. Specially for medical applications a high degree of purity is required, which is accomplished with high resolution chromatographic techniques. Affinity chromatography is considered a very high resolution chromatographic technique. In this work the adsorption isotherms and kinetics of the adsorption of lipase from Geotrichum sp on biospecific resin were determined. The resin was prepared using EAH sepharose 4B gel (Pharmacia, made to react with oleic acid as the specific ligand.The lipase was produced in a five-liter fermenter, with both complex and synthetic media. Fermentation conditions were a temperature of 30°C, an aeration of 1VVM and an agitation of 400 rpm. Maximum lipase activity was around 28 U/ml after 10 hours of fermentation for the complex medium. The kinetic model and parameters were determined by dynamic fitting to experimental results using the fourth-order Runge-Kutta method.

Lipase immobilized on the hydrophobic polytetrafluoroethene membrane with nonwoven fabric and its application in intensifying synthesis of butyl oleate.

Science.gov (United States)

Wang, Shu-Guang; Zhang, Wei-Dong; Li, Zheng; Ren, Zhong-Qi; Liu, Hong-Xia

2010-11-01

The synthesis of butyl oleate was studied in this paper with immobilized lipase. Five types of membrane were used as support to immobilize Rhizopus arrhizus lipase by following a procedure combining filtration and protein cross-linking. Results showed that hydrophobic polytetrafluoroethene membrane with nonwoven fabric (HO-PTFE-NF) was the favorite choice in terms of higher protein loading, activity, and specific activity of immobilized lipase. The factors including solvent polarity, lipase dosage, concentration, and molar ratio of substrate and temperature were found to have significant influence on conversion. Results showed that hexane (logP = 3.53) was a favorable solvent for the biosynthesis of butyl oleate in our studies. The optimal conditions were experimentally determined of 50 U immobilized lipase, molar ratio of oleic acid to butanol of 1.0, substrate concentration of 0.12 mol/L, temperature of 37 °C, and reaction time of 2 h. The conversion was beyond 91% and decreased slightly after 18 cycles. Lipase immobilization can improve the conversion and the repeated use of immobilized lipase relative to free lipase.

Biosensor Applications of MAPLE Deposited Lipase

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Valeria Califano

2014-10-01

Full Text Available Matrix Assisted Pulsed Laser Evaporation (MAPLE is a thin film deposition technique derived from Pulsed Laser Deposition (PLD for deposition of delicate (polymers, complex biological molecules, etc. materials in undamaged form. The main difference of MAPLE technique with respect to PLD is the target: it is a frozen solution or suspension of the (guest molecules to be deposited in a volatile substance (matrix. Since laser beam energy is mainly absorbed by the matrix, damages to the delicate guest molecules are avoided, or at least reduced. Lipase, an enzyme catalyzing reactions borne by triglycerides, has been used in biosensors for detection of β-hydroxyacid esters and triglycerides in blood serum. Enzymes immobilization on a substrate is therefore required. In this paper we show that it is possible, using MAPLE technique, to deposit lipase on a substrate, as shown by AFM observation, preserving its conformational structure, as shown by FTIR analysis.

Regulation of hepatic peroxisome proliferator-activated receptor alpha expression but not adiponectin by dietary protein in finishing pigs.

Science.gov (United States)

Weber, T E; Kerr, B J; Spurlock, M E

2008-10-01

Soy protein regulates adiponectin and peroxisome proliferator-activated receptor alpha (PPARalpha) in some species, but the effect of dietary soy protein on adiponectin and PPARalpha in the pig has not been studied. Therefore, the objective of this study was to determine whether soya bean meal reduction or replacement influences serum adiponectin, adiponectin mRNA, serum metabolites and the expression of PPARalpha and other genes involved in lipid deposition. Thirty-three pigs (11 pigs per treatment) were subjected to one of three dietary treatments: (i) reduced crude protein (CP) diet containing soya bean meal (RCP-Soy), (ii) high CP diet containing soya bean meal (HCP-Soy) or (iii) high CP diet with corn gluten meal replacing soya bean meal (HCP-CGM) for 35 days. Dietary treatment had no effect on overall growth performance, feed intake or measures of body composition. There was no effect of dietary treatment on serum adiponectin or leptin. Dietary treatment did not affect the abundance of the mRNAs for adiponectin, PPARalpha, PPARgamma2, lipoprotein lipase or fatty acid synthase in adipose tissue. The mRNA expression of PPARalpha, PPARgamma2, lipoprotein lipase or fatty acid synthetase in loin muscle was not affected by dietary treatment. In liver tissue, the relative abundance of PPARalpha mRNA was greater (p Soy diets when compared to pigs fed RCP-Soy or HCP-CGM diets. Hepatic mRNA expression of acyl-CoA oxidase or fatty acid synthase was not affected by dietary treatment. Western blot analysis indicated that hepatic PPARalpha protein levels were decreased (p Soy diets when compared to pigs fed the HCP-Soy diets. These data suggest that increasing the soy protein content of swine diets increases hepatic expression of PPARalpha without associated changes in body composition.

ENZYMATIC PRODUCTION OF ETHYL OLEATE ESTER USING A LIPASE FROM CANDIDA ANTARCTICA B

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N. Sampaio Neta

2012-05-01

Full Text Available Lipases are biocatalysts of great importance in different areas, being able to catalyze reactions in aqueous or organic media. Furthermore, these enzymes are capable of using several substrates being stable in a wide range of pH and temperatures. Lipases promote the esterification between fatty acids and ethanol producing oleate esters. The aim of this work is to produce ethyl oleate ester by enzymatic esterification of oleic acid with ethanol. A lipase from Candida antarctica type B was used at a temperature of 55 °C. The reaction was conducted using oleic acid, sodium sulfate anhydrous, lipase and ethanol, with a ratio of oleic acid (0.03 mol or 10 ml, lipase (0.1 mol or 0.01 g, sodium sulfate anhydrous (5 g and ethanol 99 % (100 ml. Several reaction times were studied, namely 48, 72, 96 and 120 hours. Nuclear Magnetic Resonance (1H and 13C and Infrared spectra confirmed the production of ethyl oleate ester for the studied conditions. The highest ethyl oleate production yield was obtained for 96 hours reaction time. Ethyl oleate esters have been reported to possess interesting applications in several industrial fields, such as food, aromatics, cosmetics, detergents, flavors and pharmaceuticals.

Study on fast ion loss in HL-2A tokamak

International Nuclear Information System (INIS)

Liu Yi; Sun Tengfei; Ji Xiaoquan

2012-01-01

Experiments with a high-energy deuterium neutral beam (NB) injection (30 keV, about 0.6 MW) were performed on the HL-2A tokamak. Analysis of neutron decay following the NB 'blip' injection indicates that tangentially injected beam ions are well confined, slowing down classically in the HL-2A. Anomalous losses of beam ions were observed when a beta-induced Alfven acoustic (BAAE) mode was present in the plasma. Such a high energetic particle driven mode led to fast-ion loss, showing a strong influence of the energetic particle driven mode on the fast-ion transport. (authors)

Introduction to the HL-LHC Project

Science.gov (United States)

Rossi, L.; Brüning, O.

The Large Hadron Collider (LHC) is one of largest scientific instruments ever built. It has been exploring the new energy frontier since 2010, gathering a global user community of 7,000 scientists. To extend its discovery potential, the LHC will need a major upgrade in the 2020s to increase its luminosity (rate of collisions) by a factor of five beyond its design value and the integrated luminosity by a factor of ten. As a highly complex and optimized machine, such an upgrade of the LHC must be carefully studied and requires about ten years to implement. The novel machine configuration, called High Luminosity LHC (HL-LHC), will rely on a number of key innovative technologies, representing exceptional technological challenges, such as cutting-edge 11-12 tesla superconducting magnets, very compact superconducting cavities for beam rotation with ultra-precise phase control, new technology for beam collimation and 300-meter-long high-power superconducting links with negligible energy dissipation. HL-LHC federates efforts and R&D of a large community in Europe, in the US and in Japan, which will facilitate the implementation of the construction phase as a global project.

Esterification for butyl butyrate formation using Candida cylindracea lipase produced from palm oil mill effluent supplemented medium

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Aliyu Salihu

2014-12-01

Full Text Available The ability of Candida cylindracea lipase produced using palm oil mill effluent (POME as a basal medium to catalyze the esterification reaction for butyl butyrate formation was investigated. Butyric acid and n-butanol were used as substrates at different molar ratios. Different conversion yields were observed according to the affinity of the produced lipase toward the substrates. The n-butanol to butyric acid molar ratio of 8 and lipase concentration of 75 U/mg gave the highest butyl butyrate formation of 63.33% based on the statistical optimization using face centered central composite design (FCCCD after 12 h reaction. The esterification potential of the POME based lipase when compared with the commercial lipase from the same strain using the optimum levels was found to show a similar pattern. It can be concluded therefore that the produced lipase possesses appropriate characteristics to be used as a biocatalyst in the esterification reactions for butyl butyrate formation.

Production and Characterization of Lipases by Two New Isolates of Aspergillus through Solid-State and Submerged Fermentation

Science.gov (United States)

Colla, Luciane Maria; Ficanha, Aline M. M.; Rizzardi, Juliana; Bertolin, Telma Elita; Reinehr, Christian Oliveira; Costa, Jorge Alberto Vieira

2015-01-01

Due to the numerous applications of lipases in industry, there is a need to study their characteristics, because lipases obtained from different sources may present different properties. The aim of this work was to accomplish the partial characterization of lipases obtained through submerged fermentation and solid-state fermentation by two species of Aspergillus. Fungal strains were isolated from a diesel-contaminated soil and selected as good lipases producers. Lipases obtained through submerged fermentation presented optimal activities at 37°C and pH 7.2 and those obtained through solid-state fermentation at 35°C and pH 6.0. The enzymes produced by submerged fermentation were more temperature-stable than those obtained by solid-state fermentation, presenting 72% of residual activity after one hour of exposition at 90°C. Lipases obtained through submerged fermentation had 80% of stability in acidic pH and those obtained through solid-state fermentation had stability greater than 60% in alkaline pH. PMID:26180809

Production and Characterization of Lipases by Two New Isolates of Aspergillus through Solid-State and Submerged Fermentation

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Luciane Maria Colla

2015-01-01

Full Text Available Due to the numerous applications of lipases in industry, there is a need to study their characteristics, because lipases obtained from different sources may present different properties. The aim of this work was to accomplish the partial characterization of lipases obtained through submerged fermentation and solid-state fermentation by two species of Aspergillus. Fungal strains were isolated from a diesel-contaminated soil and selected as good lipases producers. Lipases obtained through submerged fermentation presented optimal activities at 37°C and pH 7.2 and those obtained through solid-state fermentation at 35°C and pH 6.0. The enzymes produced by submerged fermentation were more temperature-stable than those obtained by solid-state fermentation, presenting 72% of residual activity after one hour of exposition at 90°C. Lipases obtained through submerged fermentation had 80% of stability in acidic pH and those obtained through solid-state fermentation had stability greater than 60% in alkaline pH.

Regioselective Alcoholysis of Silychristin Acetates Catalyzed by Lipases

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Eva Vavříková

2015-05-01

Full Text Available A panel of lipases was screened for the selective acetylation and alcoholysis of silychristin and silychristin peracetate, respectively. Acetylation at primary alcoholic group (C-22 of silychristin was accomplished by lipase PS (Pseudomonas cepacia immobilized on diatomite using vinyl acetate as an acetyl donor, whereas selective deacetylation of 22-O-acetyl silychristin was accomplished by Novozym 435 in methyl tert-butyl ether/ n-butanol. Both of these reactions occurred without diastereomeric discrimination of silychristin A and B. Both of these enzymes were found to be capable to regioselective deacetylation of hexaacetyl silychristin to afford penta-, tetra- and tri-acetyl derivatives, which could be obtained as pure synthons for further selective modifications of the parent molecule.

Transcriptome analysis of the effects of chitosan on the hyperlipidemia and oxidative stress in high-fat diet fed mice.

Science.gov (United States)

Wang, Bin; Zhang, Sicong; Wang, Xiaoya; Yang, Shuo; Jiang, Qixing; Xu, Yanshun; Xia, Wenshui

2017-09-01

Transcriptome analysis was performed to investigate the alterations in gene expression after chitosan (CS) treatment on the liver of mice fed with high-fat diet (HFD). The results showed that the body weight, the liver weight and the epididymal fat mass of HFD mice, which were 62.98%, 46.51% and 239.37%, respectively, higher than those of control mice, could be significantly decreased by chitosan supplementation. Also, high-fat diet increased both plasma lipid and liver lipid as compared with the control mice. Chitosan supplementation decreased the plasma lipid and liver lipid, increased the lipoprotein lipase (LPL) and hepatic lipase (HL) activity, increased T-AOC and decreased MDA in the liver and the epididymis adipose as compared with the HFD mice. Transcriptome analysis indicated that increased Mups, Lcn2, Gstm3 and CYP2E1 expressions clearly indicated HFD induced lipid metabolism disorder and oxidative damage. Especially, chitosan treatment decreased the Mup17 and Lcn2 expressions by 64.32% and 82.43% respectively as compared with those of HFD mice. These results indicated that chitosan possess the ability to improve the impairment of lipid metabolism as strongly associated with increased Mups expressions and gene expressions related to oxidative stress. Copyright © 2017 Elsevier B.V. All rights reserved.

MOLECULAR CLONING AND CHARACTERIZATION OF NOVEL THERMOSTABLE LIPASE FROM SHEWANELLA PUTREFACIENS AND USING ENZYMATIC BIODIESEL PRODUCTION

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Fahri Akbas

2015-02-01

Full Text Available A novel thermostable lipase from Shewanella putrefaciens was identified, expressed in Escherichia coli, characterized and used in biodiesel production. Enzyme characterization was carried out by enzyme assay, SDS-PAGE and other biochemical reactions. The recombinant lipase was found to have a molecular mass of 29 kDa and exhibited lipase activity when Tween 80 was used as the substrate. The purified enzyme showed maximum activity at pH 5.0 and at 80°C. The recombinant lipase was used for the transesterification of canola oil and waste oil. The enzyme retains 50% of its activity at 90°C for 30 minutes. It is also able to retain 20% of its activity even at 100 °C for 20 minutes. These properties of the obtained new recombinant thermostable lipase make it promising as a biocatalyst for industrial processes.

An ageing study of resistive micromegas for the HL-LHC environment

CERN Document Server

Galan, J.; Ferrer-Ribas, E.; Giganon, A.; Giomataris, I.; Herlant, S.; Jeanneau, F.; Peyaud, A.; Schune, Ph; Alexopoulos, T.; Byszewski, M.; Iakovidis, G.; Iengo, P.; Ntekas, K.; Leontsinis, S.; de Oliveira, R.; Tsipolitis, Y.; Wotschack, J.

2013-01-01

Resistive-anode micromegas detectors are in development since several years, in an effort to solve the problem of sparks when working at high flux and high ionizing radiation like in the HL-LHC (up to ten times the luminosity of the LHC). They have been chosen as one of the technologies that will be part of the ATLAS New Small Wheel project (forward muon system). An ageing study is mandatory to assess their capabilities to handle the HL-LHC environment on a long-term period. A prototype has been exposed to several types of irradiation (X-rays, cold neutrons, $^{60}$Co gammas and alphas) above the equivalent charge produced at the detector in five HL-LHC running years without showing any degradation of the performances in terms of gain and energy resolution. This study has been completed with the characterization of the tracking performances in terms of efficiency and spatial resolution, verifying the compatibility of results obtained with both resistive micromegas detectors, irradiated and non-irradiated one.

The conceptual design for the modification of HL-2A tokamak

International Nuclear Information System (INIS)

Dequan Liu

2006-01-01

The medium-sized tokamak HL-2A, based on the former ASDEX's main components has approached its rating operational parameters with I p = 450 kA and B T =2.8 T so far. The HL-2A was originally designed to operate under an axisymmetrical double-null configuration by two triplets of shaping coils located in the vacuum vessel. Because the shaping coils were set very close to the plasma column, the nulls are normally fixed and the plasma has a nearly circular cross-section. It is difficult to increase the parameters further and obtain a preferable plasma shape with certain values of triangularity and elongation. Due to the defects on upper shaping coils' electrical insulation, the HL-2A is presently just operated with lower single null divertor configuration. Additionally, the experiment has to occasionally terminate due to incidental damages of the weak parts. With the experimental progress on HL-2A, the plasma stored energy and auxiliary heating power is being increased, a more efficient, compact and tight divertor is needed. Based on present status of HL-2A tokamak and for satisfying the requirements of the experiment, the modification of HL-2A tokamak device will be carried out. The modification design of HL-2A intents to obtain optimized plasma parameters, e.g., aspect ratio, I p , b, plasma volume, certain plasma shaping with preferable elongation and triangularity, a stable vacuum vessel easy to be maintained and an advanced divertor. The primary consideration of the modification is to take all of the shaping coils out of the vessel to enlarge the plasma volume. The elongated and triangular cross section with double null of plasma is to be obtained by composite distribution of eight sets of poloidal coils. Because all poloidal coils will be located between the TF coil and the vessel, the vacuum vessel will be remade with a smaller size to make rooms for the poloidal coil system. With an optimized operation mode, the volt-second of the plasma may be increased a

Lipase production from a wild (LPF-5) and a mutant (HN1) strain of ...

African Journals Online (AJOL)

Lipase production from a wild (LPF-5) and a mutant (HN1) strain of Aspergillus niger. ... Several physical parameters (carbon source, nitrogen source, pH, ... for the development of industrial biotechnology for production of extracellular lipase.

Relationship of calcitonin mRNA expression to the differentiation state of HL 60 cells.

Science.gov (United States)

Kiefer, P; Bacher, M; Pflüger, K H

1994-05-01

Raised plasma levels of immunoreactive human calcitonin (ihCT) can be found in patients with myeloid leukemia and seem to indicate a poor prognosis. High levels were found in acute undifferentiated and acute myeloblastic leukemia. To test whether CT expression could be a marker of myeloid differentiation, we used the promyelocytic leukemia cell line HL 60 which also expresses ihCT as a model system for myeloid differentiation. Exponentially growing HL 60 cells as well as differentiation induced HL 60 cells expressed a single 1.0 Kb CT transcript. The induction of HL 60 cell differentiation along the granulocytic lineage by DMSO or HMBA had no effect on the level of CT transcripts. Induction of monocytic/macrophagic differentiation by TPA resulted in a transient, about 10-fold elevated expression of CT steady state mRNA after 24 h. In contrast to TPA, induction of HL 60 cell differentiation along the monocytic pathway by Vit D3 had no detectable effect on the level of the CT in RNA expression at corresponding time points. These findings suggest that the transient induction of CT steady state mRNA expression by TPA is rather a direct effect of the phorbol ester than commitment along the monocytic line of differentiation.

Production and application of a thermostable lipase from Serratia marcescens in detergent formulation and biodiesel production.

Science.gov (United States)

García-Silvera, Edgar Edurman; Martínez-Morales, Fernando; Bertrand, Brandt; Morales-Guzmán, Daniel; Rosas-Galván, Nashbly Sarela; León-Rodríguez, Renato; Trejo-Hernández, María R

2018-03-01

In this study, extracellular lipase was produced by Serratia marcescens wild type and three mutant strains. The maximum lipase activity (80 U/mL) was obtained with the SMRG4 mutant strain using soybean oil. Using a 2 2 factorial design, the lipase production increased 1.55-fold (124 U/mL) with 4% and 0.05% of soybean oil and Triton X-100, respectively. The optimum conditions for maximum lipase activity were 50 °C and pH 8. However, the enzyme was active in a broad range of pH (6-10) and temperatures (5-55 °C). This lipase was stable in organic solvents and in the presence of oxidizing agents. The enzyme also proved to be efficient for the removal of triacylglycerol from olive oil in cotton cloth. A Box-Behnken experimental design was used to evaluate the effects of the interactions between total lipase activity, buffer pH, and wash temperatures on oil removal. The model obtained suggested that all selected factors had a significant impact on oil removal, with optimum conditions of 550 U lipase, 45 °C, pH 9.5, with 79.45% removal. Biotransformation of waste frying oil using the enzyme and in presence of methanol resulted in the synthesis of methyl esters such as methyl oleate, methyl palmitate, and methyl stearate. © 2017 International Union of Biochemistry and Molecular Biology, Inc.

Screening of supports for immobilization of commercial porcine pancreatic lipase

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Robison Scherer

2011-12-01

Full Text Available The aim of this work is to report the performance of different supports for the immobilization of commercial porcine pancreatic lipase. The immobilization tests were carried out in several types of Accurel, activated alumina, kaolin, montmorillonite, ion exchange resins and zeolites. The characterization of the supports showed differences in terms of specific area and morphology. The characteristics of the supports influenced the amount of enzyme adsorbed, yield of immobilization and esterification activity of the resulting immobilized catalyst. The clays KSF and natural and pillared montmorillonites presented potential for use as support for lipase immobilization in terms of yield and esterification activity. Yields of immobilization of 76.32 and 52.01% were achieved for clays KSF and natural montmorillonite, respectively. Esterification activities of 754.03, 595.51, 591.88 and 515.71 U.g-1 were obtained for lipases immobilized in Accurel MP-100, Amberlite XAD-2, mordenite and pillared montmorillonite, respectively.

Lipase-catalyzed esterification of lactic acid with straight-chain alcohols

DEFF Research Database (Denmark)

Rønne, Torben Harald; Xu, Xuebing; Tan, Tianwei

2005-01-01

Enzymatic synthesis of esters of lactic acid and straight-chain alcohols with different chain lengths (C6–C18) were investigated in batch reactions with hexadecanol (C16) as the model alcohol. Cyclohexane was the best solvent for higher ester yields, and the best biocatalyst was the immobilized...... Candida antarctica lipase B (Novozym 435) as well as the textile-immobilized Candida sp. lipase. A method was established to obtain ester yields in the range of 71 to 82% for the different alcohols, and the most favorable conditions for the esterification reaction using Novozym 435 were an equimolar ratio...... of lactic acid to alcohol, each at a concentration of 120 mM each; a 50°C reaction temperature; 190 rpm shaking speed; and the addition of 100 mg molecular sieves (4 Å) for drying. The ester yield increased with increasing lipase load, and a yield of 79.2% could be obtained after 24 h of reaction at 20 wt...

Development of a lipase fermentation process that uses a recombinant Pseudomonas alcaligenes strain

NARCIS (Netherlands)

Gerritse, G; Hommes, R.W J; Quax, Wim

Pseudomonas alcaligenes M-l secretes an alkaline lipase, which has excellent characteristics for the removal of fatty stains under modern washing conditions. A fed-batch fermentation process based on the secretion of the alkaline lipase from P. alcaligenes was developed. Due to the inability of P.

Electrochemical DNA sandwich assay with a lipase label for attomole detection of DNA

DEFF Research Database (Denmark)

Ferapontova, Elena; Hansen, Majken Nørgaard; Saunders, Aaron Marc

2010-01-01

A fast and sensitive electrochemical lipase-based sandwich hybridization assay for detection of attomole levels of DNA has been developed. A combination of magnetic beads, used for pre-concentration and bioseparation of the analyte with a lipase catalyst label allowed detection of DNA with a limi...

Enzymatic resolution of (R,S-ibuprofen and (R,S-ketoprofen by microbial lipases from native and commercial sources Resolução enzimática do (R,S-ibuprofeno e (R,S-cetoprofeno por lipases microbianas de fontes nativas e comerciais

Directory of Open Access Journals (Sweden)

Patrícia de Oliveira Carvalho

2006-09-01

Full Text Available The enantioselectivity (E of native lipases from Aspergillus niger, Aspergillus terreus, Fusarium oxysporum, Mucor javanicus, Penicillium solitum and Rhizopus javanicus in the resolution of (R,S-ibuprofen and (R,S-ketoprofenenantiomers by esterification reaction with 1-propanol in isooctane was compared with known commercial Candida rugosa (Sigma and Candida antarctica (Novozym®435 lipases. In the resolution of (R,S-ibuprofen, C. rugosa lipase showed good selectivity (E = 12 while Novozym®435 (E = 6.7 and A. niger (E = 4.8 lipases had intermediate selectivities. Other enzymes were much less selective (E around 2.3 and 1.5, under tested conditions. After preliminary optimization of reaction conditions (water content, enzyme concentration and presence of additives the enantioselectivity of native A. niger lipase could be enhanced substantially (E = 15. All tested lipases showed low selectivity in the resolution of (R,S-ketoprofen because poor ester yields and low enantiomeric excess of the acid remaining were achieved.A enantioseletividade (E das lipases nativas de Aspergillus niger, Aspergillus terreus, Fusarium oxysporum, Mucor javanicus, Penicillium solitum e Rhizopus javanicus na resolução dos enantiômeros do (R,S-ibuprofeno e (R,S-cetoprofeno na reação de esterificação com 1-propanol em isoctano foi comparada com as lipases comerciais de Candida rugosa (Sigma e Candida antarctica (Novozym®435. A lipase de C. rugosa mostrou boa enantioseletividade (E = 12 comparada com as da Novozym®435 (E = 6.7, de A. niger (E=4.8 e com as outras lipases que foram muito menos seletivas (E por volta de 2.3 e 1.5 na resolução do (R,S-ibuprofeno, dentro das condições testadas. Após uma otimização preliminar das condições da reação (conteúdo de água, concentração da enzima e presença de aditivos a enantioseletividade da lipase de A. niger pôde ser substancialmente aumentada (E = 15. Todas as lipases testadas mostraram baixa

The Discharge Design of HL-2M with the Tokamak Simulation Code (TSC)

International Nuclear Information System (INIS)

Yudong Pan; Jardin, S.C.; Kes, C.

2007-01-01

We present results on the discharge design of the HL-2M tokamak, which is to be an upgrade to the existing HL-2A tokamak. We present simulation results for complete 5-sec. discharges, both double null and lower single null, for both ohmic and auxiliary heated discharges. We also discuss the vertical stability properties of the device

The Hellenic National Tsunami Warning Centre (HL-NTWC): Recent updates and future developments

Science.gov (United States)

Melis, Nikolaos S.; Charalampakis, Marinos

2014-05-01

The Hellenic NTWC (HL-NTWC) was established officially by Greek Law in September 2010. HL-NTWC is hosted at the National Observatory of Athens, Institute of Geodynamics (NOA-IG), which also operates a 24/7 earthquake monitoring service in Greece and coordinates the newly established Hellenic Unified National Seismic Network. NOA-IG and HL-NTWC Operational Centre is linked to the Civil Protection Operational Centre and serves as the official alerting agency to the General Secretariat for Civil Protection in Greece, regarding earthquake events and tsunami watch. Since August 2012, HL-NTWC acts as Candidate Tsunami Watch Provider (CTWP) under the UNESCO IOC - ICG NEAMTWS tsunami warning system (NEAM: North-Eastern Atlantic, the Mediterranean and connected seas) and offers its services to the NEAMTWS system. HL-NTWC has participated in all Communication Test Exercises (CTE) under NEAMTWS and also it has provided tsunami scenarios for extended system testing exercises such as NEAMWAVE12. Some of the recent developments at HL-NTWC in Greece include: deployment of new tide gauge stations for tsunami watch purposes, computation of tsunami scenarios and extending the database in use, improving alerting response times, earthquake magnitude estimation and testing newly established software modules for tsunami and earthquake alerting (i.e. Early-Est, SeisComP3 etc.) in Greece and the Eastern Mediterranean. Although funding today is limited, an advantage of the participation in important EC funded research projects, i.e. NERIES, NERA, TRANSFER, NEAMTIC and ASTARTE, demonstrates that collaboration of top class Research Institutions that care to produce important and useful results in the research front in Europe, can facilitate towards developing and operating top class Operational Centers, useful for Civil Protection purposes in regions in need. Last, it is demonstrated that HL-NTWC collaboration with important key role Research Centers in the Security and Safety issues (e

Lipase assay in soils by copper soap colorimetry.

Science.gov (United States)

Saisuburamaniyan, N; Krithika, L; Dileena, K P; Sivasubramanian, S; Puvanakrishnan, R

2004-07-01

A simple and sensitive method for the estimation of lipase activity in soils is reported. In this method, 50mg of soil is incubated with emulsified substrate, the fatty acids liberated are treated with cupric acetate-pyridine reagent, and the color developed is measured at 715 nm. Use of olive oil in this protocol leads to an estimation of true lipase activity in soils. The problem of released fatty acids getting adsorbed onto the soil colloids is obviated by the use of isooctane, and separate standards for different soils need not be developed. Among the various surfactants used for emulsification, polyvinyl alcohol is found to be the most effective. Incubation time of 20 min, soil concentration of 50 mg, pH 6.5, and incubation temperature of 37 degrees C were found to be the most suitable conditions for this assay. During the process of enrichment of the soils with oil, interference by the added oil is avoided by the maintenance of a suitable control, wherein 50 mg of soil is added after stopping the reaction. This assay is sensitive and it could be adopted to screen for lipase producers from enriched soils and oil-contaminated soils before resorting to isolation of the microbes by classical screening methods.

The Purification and Characterization of Lipases from Lasiodiplodia theobromae, and Their Immobilization and Use for Biodiesel Production from Coconut Oil.

Science.gov (United States)

Venkatesagowda, Balaji; Ponugupaty, Ebenezer; Barbosa-Dekker, Aneli M; Dekker, Robert F H

2017-12-18

The coconut kernel-associated fungus, Lasiodiplodia theobromae VBE1, was grown on coconut cake with added coconut oil as lipase inducer under solid-state fermentation conditions. The extracellular-produced lipases were purified and resulted in two enzymes: lipase A (68,000 Da)-purified 25.41-fold, recovery of 47.1%-and lipase B (32,000 Da)-purified 18.47-fold, recovery of 8.2%. Both lipases showed optimal activity at pH 8.0 and 35 °C, were activated by Ca 2+ , exhibited highest specificity towards coconut oil and p-nitrophenyl palmitate, and were stable in iso-octane and hexane. Ethanol supported higher lipase activity than methanol, and n-butanol inactivated both lipases. Crude lipase immobilized by entrapment within 4% (w/v) calcium alginate beads was more stable than the crude-free lipase preparation within the range pH 2.5-10.0 and 20-80 °C. The immobilized lipase preparation was used to catalyze the transesterification/methanolysis of coconut oil to biodiesel (fatty acyl methyl esters (FAMEs)) and was quantified by gas chromatography. The principal FAMEs were laurate (46.1%), myristate (22.3%), palmitate (9.9%), and oleate (7.2%), with minor amounts of caprylate, caprate, and stearate also present. The FAME profile was comparatively similar to NaOH-mediated transesterified biodiesel from coconut oil, but distinctly different to petroleum-derived diesel. This study concluded that Lasiodiplodia theobromae VBE1 lipases have potential for biodiesel production from coconut oil.

The interactions between lipase and pyridinium ligands investigated by electrochemical and spectrophotometric methods

Directory of Open Access Journals (Sweden)

Simona Patriche

2016-04-01

Full Text Available The interaction between pyridinium ligands derived from 4,4’-bipyridine (N,N’-bis(p-bromophenacyl-4,4’-bipyridinium dibromide – Lr and (N,N’-bis(p-bromophenacyl-1,2-bis (4-pyridyl ethane dibromide – Lm with lipase enzyme was evaluated. The stability of the pyridinium ligands, having an essential role in biological systems, in 0.1 M KNO3 as supporting electrolyte is influenced by the lipase concentration added. The pH and conductometry measurements in aqueous solution suggest a rapid ionic exchange process. The behavior of pyridinium ligands in the presence of lipase is investigated by cyclic voltammetry and UV/Vis spectroscopy, which indicated bindings and changes from the interaction between them. The voltammograms recorded on the glassy carbon electrode showed a more intense electronic transfer for the Lr interaction with lipase compared to Lm, which is due to the absence of mobile ethylene groups from Lr structure.

Pancreatitis with normal lipase and amylase in setting of end-stage renal disease.

Science.gov (United States)

Sharma, Anuj; Masood, Umair; Khan, Babar; Chawla, Kunal; Manocha, Divey

2017-09-01

Pancreatitis with normal lipase and amylase level is a rare phenomenon. This is especially true in patient with end-stage renal disease as lipase and amylase are renally excreted. Literature review reveals previous case report of pancreatitis with normal lipase and amylase level, however, none of them occurred in the setting of end-stage renal disease. Our case is the first such reported case of pancreatitis in such setting. Here we report a 30year old male with past medical history of end-stage renal disease who presented in emergency department with acute abdominal pain. Laboratory work up revealed normal lipase and amylase level. However, radiological work up was consistent with pancreatitis. This case report highlight the importance of taking the overall clinical picture rather than laboratory work up to rule in or rule out the diagnosis of pancreatitis. Furthermore, this should also serve an important reminder for clinicians to further investigate where clinical suspicion for pancreatitis is high. Copyright © 2017 Elsevier Inc. All rights reserved.

Biodiesel production from Nannochloropsis gaditana lipids through transesterification catalyzed by Rhizopus oryzae lipase.

Science.gov (United States)

Navarro López, Elvira; Robles Medina, Alfonso; González Moreno, Pedro Antonio; Esteban Cerdán, Luis; Martín Valverde, Lorena; Molina Grima, Emilio

2016-03-01

Biodiesel (fatty acid methyl esters, FAMEs) was produced from saponifiable lipids (SLs) extracted from wet Nannochloropsis gaditana biomass using methanolysis catalyzed by Rhizopus oryzae intracellular lipase. SLs were firstly extracted with ethanol to obtain 31 wt% pure SLs. But this low SL purity also gave a low biodiesel conversion (58%). This conversion increased up to 80% using SLs purified by crystallization in acetone (95 wt% purity). Polar lipids play an important role in decreasing the reaction velocity - using SLs extracted with hexane, which have lower polar lipid content (37.4% versus 49.0% using ethanol), we obtained higher reaction velocities and less FAME conversion decrease when the same lipase batch was reused. 83% of SLs were transformed to biodiesel using a 70 wt% lipase/SL ratio, 11:1 methanol/SL molar ratio, 10 mL t-butanol/g SLs after 72 h. The FAME conversion decreased to 71% after catalyzing three reactions with the same lipase batch. Copyright © 2015 Elsevier Ltd. All rights reserved.

Olive pomace valorization by Aspergillus species: lipase production using solid-state fermentation.

Science.gov (United States)

Oliveira, Felisbela; Moreira, Cláudia; Salgado, José Manuel; Abrunhosa, Luís; Venâncio, Armando; Belo, Isabel

2016-08-01

Pollution by olive mill wastes is an important problem in the Mediterranean area and novel solutions for their proper management and valorization are needed. The aim of this work was to optimize a solid-state fermentation (SSF) process to produce lipase using olive pomace (OP) as the main source of nutrients by several Aspergillus spp. Optimized variables in two different designs were: ratio between olive pomace and wheat bran (OP:WB), NaNO3 , Czapek nutrients, fermentation time, moisture content (MC) and temperature. Results showed that the mixture OP:WB and MC were the most significant factors affecting lipase production for all fungi strains tested. With MC and temperature optimization, a 4.4-fold increase in A. ibericus lipase was achieved (90.5 ± 1.5 U g(-1) ), using a mixture of OP and WB at 1:1 ratio, 0.02 g NaNO3 g(-1) dry substrate, absence of Czapek nutrients, 60% of MC and incubation at 30 °C for 7 days. For A. niger and A. tubingensis, highest lipase activity obtained was 56.6 ± 5.4 and 7.6 ± 0.6 U g(-1) , respectively. Aspergillus ibericus was found to be the most promising microorganism for lipase production using mixtures of OP and WB. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Novel Lipases: Expression and Improvement for Applied Biocatalysis = Nuevas lipasas: expresión y mejoras para biocatálisis aplicada

OpenAIRE

Infanzón Ramos, Belén

2017-01-01

This thesis is focused in the identification and improvement of lipases for biotechnological application. The importance of lipases is increasing in several industries. However, the commercial use of lipases is still a drawback in the economics of the lipase-based industrial applications. There are many tools for improving and adapting the enzyme properties to the desired requirements of a process that could lead lipase catalysis through a cost-effective process. In this context, the main obj...

Lipase activity in vesiclular systems: characterization of candida cylindracea lipase and its activity in polymerizable dialkylammonium surfactant vesicles

NARCIS (Netherlands)

Mosmuller, E.W.J.; Franssen, M.C.R.; Engbersen, Johannes F.J.

1993-01-01

Lipase from Candida cylindracea (CCL) was incorporated into polymerizable positively charged dialkylammonium bromide surfactant vesicles. The enzyme was incorporated by the use of the dehydration-rehydration method or by incubation. In the latter case, trapping efficiencies of up to 100% could be

Thermostable, alkaline and detergent-tolerant lipase from a newly isolated thermophilic Bacillus stearothermophilus.

Science.gov (United States)

Ben Bacha, Abir; Moubayed, Nadine M S; Abid, Islam

2015-04-01

Lipases are the enzymes of choice for laundry detergent industries, owing to their triglyceride removing ability from the soiled fabric, which eventually reduces the usage of phosphate-based chemical cleansers in the detergent formulation. In this study, a novel thermo-alkaline lipase-producing strain identified as Bacillus stearothermophilus was isolated from the soil samples of olive oil mill. Enhanced lipase production was observed at 55 degrees C, pH 11 and after 48 h of incubation. Among the substrates tested, xylose (a carbon source), peptone (a nitrogen source) and olive oil at a concentration of 1% were suitable substrates for enhancing lipase production. MgSO4 and Tween-80 were suitable substrates for maximizing lipase production. The enzyme was purified to homogeneity by a single CM-Sephadex column chromatography and revealed molecular mass of 67 kDa. The enzyme (BL1) was active over a wide range of pH from 9.0 to 13.0, with an optimum at pH 11.0, exhibited maximal activity at 55 degreesC and retained more than 70% of its activity after incubation at 70 degrees C or pH 13 for 0.5 h or 24 h, respectively. The enzyme hydrolyzed both short and long-chain triacylglycerols at comparable rates. BL1 was studied in a preliminary evaluation for use in detergent formulation solutions. This novel lipase showed extreme stability towards non-ionic and anionic surfactants after pre-incubation for 1 h at 40 degrees C, and good stability towards oxidizing agents. Additionally, the enzyme showed excellent stability and compatibility with various commercial detergents, suggesting its potential as an additive in detergent formulations.

Synthesis and Structures of Two Lanthanide Complexes Containing a Mixed Ligand System: [Ln(Phen){sub 2}(L){sub 3}(HL)]·H{sub 2}O [Ln = La, Ce; Phen = Phenanthroline; HL = Salicylic Acid

Energy Technology Data Exchange (ETDEWEB)

Iravani, Effat [UNiv. of Applied Science and Technology, Tehran (Iran, Islamic Republic of); Nami, Navabeh; Nabizadeh, Fatemeh; Bayani, Elham [Islamic Azad Univ., Mazandaran (Iran, Islamic Republic of); Neumueller, Bernhard [Philipps-Universitat Marburg, Marburg (Germany)

2013-11-15

The reaction of LnCl{sub 3}·7H{sub 2}O [Ln = La (1), Ce (2)] with salicylic acid (HL) and 1,10-phenanthroline (Phen) at 20 .deg. C in H{sub 2}O/ethanol gave after work-up and recrystallization two novel lanthanide complexes with general formula [Ln(Phen){sub 2}(L){sub 3}(HL)]·H{sub 2}O. Compounds 1 and 2 were characterized by IR and UV-Vis spectroscopy, TGA, CHN as well as by X-ray analysis. According to these results, compounds 1 and 2 are isostructural and contain Ln{sup 3+} ions with coordination number nine. Complexes 1 and 2 consist of two Phen, one neutral HL and three L anions (two L anions act as monodentate ligands and the third one is chelating to Ln{sup 3+}). Thermal decomposition led to primary loss of the Phen molecules. Then HL molecules and finally L moieties left the material to give Ln{sub 2}O{sub 3}.

A hepatic amino acid/mTOR/S6K-dependent signalling pathway modulates systemic lipid metabolism via neuronal signals.

Science.gov (United States)

Uno, Kenji; Yamada, Tetsuya; Ishigaki, Yasushi; Imai, Junta; Hasegawa, Yutaka; Sawada, Shojiro; Kaneko, Keizo; Ono, Hiraku; Asano, Tomoichiro; Oka, Yoshitomo; Katagiri, Hideki

2015-08-13

Metabolism is coordinated among tissues and organs via neuronal signals. Levels of circulating amino acids (AAs), which are elevated in obesity, activate the intracellular target of rapamycin complex-1 (mTORC1)/S6kinase (S6K) pathway in the liver. Here we demonstrate that hepatic AA/mTORC1/S6K signalling modulates systemic lipid metabolism via a mechanism involving neuronal inter-tissue communication. Hepatic expression of an AA transporter, SNAT2, activates the mTORC1/S6K pathway, and markedly elevates serum triglycerides (TGs), while downregulating adipose lipoprotein lipase (LPL). Hepatic Rheb or active-S6K expression have similar metabolic effects, whereas hepatic expression of dominant-negative-S6K inhibits TG elevation in SNAT2 mice. Denervation, pharmacological deafferentation and β-blocker administration suppress obesity-related hypertriglyceridemia with adipose LPL upregulation, suggesting that signals are transduced between liver and adipose tissue via a neuronal pathway consisting of afferent vagal and efferent sympathetic nerves. Thus, the neuronal mechanism uncovered here serves to coordinate amino acid and lipid levels and contributes to the development of obesity-related hypertriglyceridemia.

Production and characterization of lipase from Bacillus ...

African Journals Online (AJOL)

Jane

2011-10-10

Oct 10, 2011 ... properties of fats at high temperature and increased ..... Effect of growth medium pH on lipase activity, protein concentration and B. stearothermophilus growth. .... inactivation after 30 min of incubation in 10 mM Cu+2 ions.

Lipase-catalyzed highly enantioselective kinetic resolution of boron-containing chiral alcohols.

Science.gov (United States)

Andrade, Leandro H; Barcellos, Thiago

2009-07-16

The first application of enzymes as catalysts to obtain optically pure boron compounds is described. The kinetic resolution of boron-containing chiral alcohols via enantioselective transesterification catalyzed by lipases was studied. Aromatic, allylic, and aliphatic secondary alcohols containing a boronate ester or boronic acid group were resolved by lipase from Candida antartica (CALB), and excellent E values (E > 200) and high enantiomeric excesses (up to >99%) of both remaining substrates and acetylated product were obtained.

The Supervisory Control System for the HL-2A Neutral Beam Injector

Science.gov (United States)

Li, Bo; Li, Li; Feng, Kun; Wang, Xueyun; Yang, Jiaxing; Huang, Zhihui; Kang, Zihua; Wang, Mingwei; Zhang, Guoqing; Lei, Guangjiu; Rao, Jun

2009-06-01

Supervisory control and protection system of the neutral beam injector (NBI) in the HL-2A tokamak is presented. The system is used for a safe coordination of all the main NBI subsystems. Because the system is based on computer networks with its transmission medium of optical fiber, its advantages in high operational stability, reliability, security and flexible functional expandability are clearly shown during the NBI commissioning and heating experiment in HL-2A.

99MTC-HL91 spect image versus 18F-FDG PET for detection of head and neck carcinoma

International Nuclear Information System (INIS)

Chu, L.S.; Liu, R.S.; Chou, K.L.; Yang, B.H.; Liao, S.Q.; Yeh, S.H.

2004-01-01

Objective: Tumor hypoxia is a major complication of oncologic cell switch for chemotherapy(C/T) and / or radiotherapy(R/T). Such lesions detected by selective modem conventional examination remains difficult. 99mTc-HL91 is a potential agent for imaging hypoxic tissue in vivo. This study aimed to assess efficacy of 99mTc- HL91 in imaging of head and neck cancer and compared the result with 18F-fluorodeoxyglucose(FDG)PET. Methods: Sixteen pts with head and neck cancers (7 hypopharyngeal cancers, 4 laryngeal cancers, 5 tongue base cancers) were enrolled in this study. Primary tumors and suspicious local,regional metastases were diagnosed by clinical examination, CT/MRI , and biopsy. After intravenous injection of 740 MBq of 99mTc-HL91, whole body planar scan and regional SPECT at 2hr postinjection were performed. Tumor lesion -to- normal background(T/N) ratios with 3x3 pixels of background ROI were also measured. The reference range of T/N ratio greater 3.0 defined +, close to 2.4 defined +/- and less than 1.5 defined as -. The FDG images with dedicated PET system was performed at 4hr after completion of 99mTc-HL91 study. The visualized tumors uptake with ratio of standardized uptake value (SUV) greater than 2.5 defined as +.. less than 2.5 defined -. Results: In 7 hypopharyngeal cancers, there are 2FDG+/HL91+, 3FDG+/HL91-, 2FDG+/HL91+/-, In 4 laryngeal cancers, there are 3FDG+/HL91-, 1FDG+/HL91 +/-. In 5 tongue base cancers, there are 5FDG+/HL91-.(Table 1). The T/N ratios of all head and neck cancers in primary tumor and regional lymph nodes were ranged from l.3/1.5 and 1.1/1.2 respectively. The frequency of FDG + in hypopharyngeal cancers is 1.0,in laryngeal cancers is 1.0 and in tongue base cancers is 1.0. The frequency of HL91+/+/- in hypopharyngeal cancers is 0..58,in laryngeal cancers is 0.25.and in tongue base cancers is 0. The overall detection rate of head and neck cancer by FDG+ in this study is 100% and overall detection rate of local-regional hypoxia, by