Pancreatin hydrolysis

Hydrolytic enzymes Pancreatin Hydrolysis of starch (amylase), fat (lipase), and protein (protease) Porcine pancreas Digestive aid... 

Enzymic hydrolysis of PGA by crude extracts of papain and pancreatin was carried out as described by Miller 27). Samples withdrawn at intervals were analyzed for free amino groups using a ninhydrin reaction 41). Values were corrected for the ninhydrin reaction of an enzymic digest which contained no PGA. 

Figure 7. Effect of radiation on susceptibility of PGA to enzymic hydrolysis by pancreatin...

Pancreatic and malt amylases gradually lose their activity in the aqueous dispersions in which they act. As above noted, there is good evidence that this is due to a destructive hydrolysis of the enzyme. The destructive action of water upon enzyme is less pronounced in the presence of substrate, probably because the combination of enzyme with substrate serves to some extent to protect the enzyme from hydrolysis. It is less rapid in solutions of commercial pancreatin and in water extracts of malt than it is in solutions of purified pancreatic and malt amylases, doubtless because of the presence in the former of substances which are products of protein hydrolysis (proteoses, peptones, polypeptids, amino acids) and whose presence therefore tends to retard further protein hydrolysis and thus to protect the enzyme protein from hydrolytic destruction, or at least to diminish the rate at which such deterioration of the enzyme occurs. 

Tower et al. (1962) have employed enzymatic hydrolysis with pancreatin preparations for liberation of glutamine and asparagine from proteins. Under the conditions employed, proteins were not hydrolyzed to an extent of more than 50-80 %, but after correcting for incomplete hydrolysis, yields of the two amides were in excellent agreement with theoretical values. 

Enzymatic hydrolysis of (la,2p,3a)-2-[(benzyloxy)methyl]-4-cyclopenten-l,3-diol diacetate has been demonstrated by Griffith and Danishefsky to obtain the corresponding monoester using acetylcholine esterase from electric eel [53,54]. We have described the enantioselective asymmetric hydrolysis of (la,2p,3a)-2-[(benzyloxy) methyl]-4-cyclopenten-l,3-diol diacetate 28 (Figiu-e 16.7) to the corresponding (h-)-monoacetate 29 by lipase PS-30 from Pseudomonas cepacia and pancreatin. A... 

The first data on the enzymes of the pancreatic juice were furnished by Cl. Bernard in 1855 and Corvisart in 1858. It is to the latter that we owe the name of pancreatin, given to the active constituents of the pancreatic juice. Danilewsky, in 1862, isolated from a maceration of pancreas three enzymes, one amylolytic, a second proteolytic, and finally a third, capable of emulsifying and of saponifying fatty substances. Kiihnc, in 1867, first drew attention to the difference which exists between the chemical action of pepsin and that of the pancreatic enzyme. He showed the production, in this second action, of tyrosin and leucin, and also of those ill-defined residues from the hydrolysis of albuminoids which he called anti-peptones. He then characterized this proteolytic enzyme as a new enzyme, distinct from pepsin, and gave to it the name of trypsin. 

The present experiments used a method based on the work of Mauron t al. (1955) and Steinhart and Kirchgessner (1973) and consisting of a two-step hydrolysis, using first pepsin in a closed system, and then pancreatin in a dialysis bag (Savoie et al.> 1980 Gauthier et al., 1982). 

To start the second step of the hydrolysis, 15 ml of pancreatin solution (5 mg/ml, hog pancreas 5X) in phosphate buffer was introduced in the bag and mixed with the products of pectic digestion. Pancreatic hydrolysis products then were continuously collected as they were dialyzed for various periods of up to 24 hours. The amount of nitrogen released was determined by an Auto Analyzer (using the method no 329-74 W/B of Technicon, Tarrytown, N.Y.). Samples of dialysate and undigested protein fractions were hydrolyzed for 24 h in 6 N HCl at lOO C. Amino acid content was evaluated by high performance liquid chromatography (Vachon al., 1982). 

The B.P. method of assay for trypsin in pancreatin is based on the fact that amino-acids are formed by hydrolysis of protein by trypsin formaldehyde forms methylene compounds with the amino-groups, the carbonyl groups being free for titration with alkali. This method, due to Evers and Smith, uses purified casein adjusted to pH 7 before the addition of formaldehyde and then titration to pH 8 7. A slightly modified method is the following ... 

Enzymic in-vitro digestion (ALVgnj). This method is based on the hydrolysis of the food with pepsin followed by pancreatin, with simultaneous dialysis and determination of the liberated... 

An accelerating effect of pancreatin containing a mixtiu e of enzymes (including Hpase, amylase, a-chymotrypsin, trypsin and protease) on the hydrolysis of P3HB, but not PLLA, has been observed in this study. The degradation rate of P3HB was accelerated about threefold in comparison to simple hydrolysis [38]. There are only a few other reports on this topic in the literature. For example, microparticles made of a PHB-10.8%HV/PCL (80/20)... 

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