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Anti-Obesity Potential of Indian Traditional Medicinal Plants and Their Phytochemicals
Published in Parimelazhagan Thangaraj, Medicinal Plants, 2018
Vellingiri Vadivel, Pichai Venkatalakshmi, Pemaiah Brindha
Gastric and lingual lipases are responsible for partial hydrolysis of dietary triacylglycerol into free acids and diacylglycerol. This partial digestion in the stomach forms large fat molecule which undergoes emulsification with bile salts to form small droplets of fat. A physical property of emulsion influences the efficiency of digestion. In the emulsion, dietary triglycerides and diglycerides in the centre of droplet followed by a mixture of polar lipids, phospholipids, cholesterol and free fatty acids; which are later coated with oligosaccharides, denatured proteins and bile salts and form a very complex structure. The pancreatic lipase interacts with emulsion droplets, which continuously change its physical properties as its products are formed, leaving the surface during the process of hydrolysis. Complete hydrolysis process results into free fatty acid, monoacylglycerols and diacylglycerols, which bind with cholesterol, bile salts, fat soluble vitamins and lysophosphatidic acid to form mixed micelles and can be absorbed by enterocytes. Pancreatic lipase uses a pancreatic protein colipase as a cofactor to facilitate lipolytic activity. Phosphatidyl choline inhibits the lipase-substrate complex. Colipase reverses to interact with the scarce surface of the substrate and stabilizes its conformation (Mukherjee et al. 2003; Shi et al. 2004).
The gastrointestinal tract
Published in Martin Andrew Crook, Clinical Biochemistry & Metabolic Medicine, 2013
Some bacteria within the gut lumen contain enzymes that catalyse the deconjugation of bile salts; unconjugated bile salts emulsify fat less effectively than conjugated ones and this may contribute to fat malabsorption. Triglycerides are emulsified by bile salts within the duodenum. They are hydrolysed by pancreatic lipase at the glycerol/fatty acid bond, primarily in positions 1 and 3. The end products are mainly 2-monoglycerides, some diglycerides and free fatty acids. Colipase, a peptide coenzyme secreted by the pancreas, is essential for lipase activity. It anchors lipase at the fat/water interface, prevents the inhibition of the enzyme by bile salts and reduces its pH optimum from about 8.5 to about 6.5; the latter is the pH in the upper intestinal lumen.
Accident and Emergency
Published in Nagi Giumma Barakat, Get Through, 2006
Fat digestion usually starts in the mouth and stomach; an emulsion is produced, and small amounts of triglycerides are hydrolysed in the stomach. When the acidic stomach contents reach the duodenum, secretin is released from the duodenal mucosa into the portal circulation. This stimulates the pancreas to produce and release bicarbonate, lipase and colipase into the duodenum. Lipase and colipase act at the surface of particles and hydrolyse tri- and monoglycerides and fatty acids. The formation of mixed micelles is the last step, involving interaction of fatty acids and monoglycerides with bile acids. Vitamins D, E and K require these micelles for their absorption.
Oral delivery of solid lipid nanoparticles: underlining the physicochemical characteristics and physiological condition affecting the lipolysis rate
Published in Expert Opinion on Drug Delivery, 2021
Mohammad Mahmoudian, Solmaz Maleki Dizaj, Sara Salatin, Raimar Löbenberg, Maryam Saadat, Ziba Islambulchilar, Hadi Valizadeh, Parvin Zakeri-Milani
Digestion of dietary lipid is initiated by lingual lipase, which is secreted by a serous gland in the mouth and continued in the stomach. And, 5–40% of total triacylglycerols (TAGs) are converted into free fatty acids (FFAs), diacylglycerols (DAGs), and monoacylglycerols (MAGs) by gastric lipases [72–75]. Most of the orally administered lipids are mainly hydrolyzed in the small intestine. Digestive juices of small intestine contain different types of lipases: human pancreatic lipase (HPL), colipase, carboxy ester hydrolase (CEH), Pancreatic phospholipase A2 (PPA2), two human pancreatic lipase-related proteins (HPLRP1 and HPLRP2), and endogenous biosurfactants including bile salts, and phospholipids. In the small intestine, 70–90% of TAGs are hydrolyzed into DAGs, MAGs, and FFAs by HPL. 40–70% of total TAGs are converted into two molecules of FFAs and one molecule of 2-monoglyceride (2-MG). The resulted 2-MGs are hydrolyzed by CEH and PLRP 2 to yield a third FA and glycerol [7,24,72,75]. The point that should be noticed is lipolysis occurs at the lipid-water interface of the lipids. Colipase, as a cofactor of HPL, forms a complex with HPL and facilitates its adsorption onto the surface of the lipids [7,75,76]. Colipase and colipase/lipase complex require a hydrophobic area of 1.5–5 and 9 nm2, respectively, to form a lipid–water interface binding site [76]. The resulted monoglycerides and FAs, as lipolysis products, leave the surface of the lipid droplets and form mixed micelles with endogenous biosurfactants; phospholipids, and bile salts that are secreted by the liver [24,75].
Non-linearity and gaps in results distribution over successive Roche Lipase method applications: improvement but persistence
Published in Scandinavian Journal of Clinical and Laboratory Investigation, 2019
Marie-Aude Robert de Rancher, Camille Gobeaux-Chenevier, Hervé Lemarechal, Rana Alkouri, Didier Borderie, Dominique Bonnefont-Rousselot, Denis Monneret
Venous blood was collected into lithium heparinized tubes with separator gel, then centrifuged for 10 min (blood collection tube manufacturers and speed centrifugations have changed over the study period). Plasma lipase activity was measured using an enzymatic colorimetric assay on the Modular®P800 (Roche reagents kits, ref#11821822216), the Cobas®c501 (Roche reagents kits, ref#03029590322), and the Cobas®C701 (Roche reagents kits, ref#07041918190), which use the 1,2-O-dilauryl-rac-glycero-3-glutaric acid-(6-methylresorufin) ester as a chromogenic lipase substrate with colipase from porcine pancreas, and with the C.f.a.s calibrator from recombinant human pancreas (Roche, ref#10759350190). According to the manufacturer, the analytical characteristics are as follows: limit of detection (LOD): 3 U/L; limit of quantification (LOQ): 5 U/L (i.e. the lowest lipase activity corresponding to an inter-series coefficient of variation <20%); limit of linearity (LOL): 300 U/L; inter-assay analytical coefficient of variation (CVa): 0.7% (mean 35.3 U/L)–1.3% (mean 71.7 U/L) on the Modular®P800 (English technical sheet, version 11-2015, V18.0), 2.1% (mean 28.8 U/L)–1.7% (mean 320 U/L) on the Cobas®c501 (French technical sheet, version 11-2015, V12.0), and 3.5% (mean 12.0 U/L)–2.0% (mean 286 U/L) on the Cobas®C701 (French technical sheet, version 2018-02, V2.0).
Improvement of Mineral Absorption and Nutritional Properties of Citrullus vulgaris Seeds Using Solid-State Fermentation
Published in Journal of the American College of Nutrition, 2020
Prince Chawla, Vinus Kumar, Aarti Bains, Rajat Singh, Pradeep Kumar Sadh, Ravinder Kaushik, Naveen Kumar
Human pancreatic lipase, α-amylase, colipase, pepsin (2080 units per mg of protein), bovine serum albumin, mucin, trypsin, chymotrypsin, and pancreatin were purchased from Sigma Chemical Co. (Madrid, Spain). Six well transwell plates, cell culture flasks (25 cm2), and plastic dishes were procured from Corning, New York, NY, USA. The human ferritin enzyme-linked immunosorbent assay (ELISA) kit (SEA518Hu 96 Tests) was procured from Cloud Clone-Corp., Houston, USA. Chemicals used during the research were of cellular and analytical reagent (AR) grade, respectively. Triple-distilled water and acid-washed glassware were used throughout the experiments.