Hydrolysis lipases

Acylglycerols can be hydrolyzed by heating with acid or base or by treatment with lipases. Hydrolysis with alkali is called saponification and yields salts of free fatty acids and glycerol. This is how soap (a metal salt of an acid derived from fat) was made by our ancestors. One method used potassium hydroxide potash) leached from wood ashes to hydrolyze animal fat (mostly triacylglycerols). (The tendency of such soaps to be precipitated by Mg and Ca ions in hard water makes them less useful than modern detergents.) When the fatty acids esterified at the first and third carbons of glycerol are different, the sec-... 

Figure 13.23 Lipase hydrolysis to (R)-glycidyl butyrate (Ladner, 1984).

Vander Wal, R.J. (1960) Calculation of the distribution of the saturated and unsaturated acyl groups in fats, from pancreatic lipase hydrolysis data. J. Am. Oil Chem. Soc., 37, 18-20. 

Lipase Hydrolysis of triglycerides of simple fatty acids, yielding mono- and diglycerides, glycerol, and free fatty acids. 

Lipase Hydrolysis of triglycerides of simple fatty acids. 

Figure 10-3 The Course of Pancreatic Lipase Hydrolysis of Tricaprylin. MG = monoglycerides, DG = diglycerides, TG = triglycerides. Source. From A. Boudreau and J.M. deMan, The Mode of Action of Pancreatic Lipase on Milkfat Glycerides, Can. J. Biochem., Vol. 43, pp. 1799-1805, 1965.

Blaner WS, Obunike JC, Kurlandsky SB, al-Haideri M, Piantedosi R, Deckelbaum RJ, and Goldberg IJ (1994) Lipoprotein lipase hydrolysis of retinyl ester. Possible implications for retinoid uptake by cells. Journal of Biological Chemistry 269,16559-65. 

This method (Fig. 9.5 B) was designed to test whether any inhibition reaction occurred in the presence of a water-insoluble substrate during lipase hydrolysis. Lipase was injected into the reaction vessel of a pH-stat containing the emulsified substrate maintained under vigorous stirring. The inhibitor was injected a few minutes after lipase addition. Lipase activity was then continuously recorded (Fig. 9.5 B). 

The rate of tributyrin hydrolysis by HGL, RGL or PPL was determined as a function of the orlistat concentration (Fig. 9.18 A) [51]. Orlistat was injected into a tributyrin emulsion 1 min prior to the enzyme addition and the initial lipase hydrolysis rate was measured. As shown from the curve in Fig. 9.18A, the rate of tributyrin hydrolysis by HGL, RGL or PPL decreased similarly with increasing the final orlistat concentration. The inhibitor concentration which reduced the hpase activity to 50% (I50) of its initial value was around 10 pM. 

Role of lipoprotein lipase Hydrolysis of triglycerides from VLDL and chylomicrons... 

The conditions of lipase hydrolysis and enhanced CL reaction were then optimized independently using serum sample spiked with porcine pancreas. Effect of incubation time on CL intensity was investigated the CL intensity increased with an increase in time up to 150 min. The recommended incubation time was 90 min. The maximum and constant CL intensity was obtained with HDI-laurate concentration above 1.0 nmiol/L. The observed Km value estimated from... 

For the fiee lipase hydrolysis tests, the substrate was prepared by mixing 30-70 mL of the selected oil with 70-30 mL of gum Arabic solution (7% w/v) containing free CRL (Table 2) and fixing the fioe lipase loading values (1 mL, 5 mg mL ). 

Fig. 3.5-2 Resolution of a racemic ester using lipase hydrolysis followed by a three-phase separation.

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