Protein derivatives, hydrolysis

Hydrolyzed Vegetable Protein. To modify functional properties, vegetable proteins such as those derived from soybean and other oil seeds can be hydrolyzed by acids or enzymes to yield hydrolyzed vegetable proteins (HVP). Hydrolysis of peptide bonds by acids or proteolytic enzymes yields lower molecular weight products useful as food flavorings. However, the protein functionaHties of these hydrolysates may be reduced over those of untreated protein. 

When proteins undergo hydrolysis, you wind up with 22 a amino acids, 20 of which are regulcir amino acids and 2 of which are derived amino acids. Amino acids are amphoteric (they possess the characteristics of both acids and bases and can react as either) because both acidic and basic groups are present. An internal acid-base reaction produces a dipolar ion known as a zwitterion (you can see the general structure of one in Figure 16-33). 

Pentosidine is determined by HPLC with spectrofluorimetric detection (excitation and emission wavelengths of 335 and 385 nm, respectively) (S14), although immunochemical and ELISA assays for determination of various protein oxidative modification products have become increasingly popular (08). Protein-aldehyde adducts can be estimated using adduct-specific antibodies (U2, Wl). Another approach requires stabilization of adducts, producing derivatives resistant to conditions used in protein acid hydrolysis and quantification of hydrolysis products by gas chromatography-mass spectrometry (R7). 

The soluble proteins derived from elastin retain the yellow color of the fibrous protein, and also its strong blue-white fluorescence, and the pigment cannot be removed by further mild hydrolysis and exhaustive dialysis or repeated precipitation with alcohol. It thus appears that a fluores-... 

These are proteins derived by partial to complete hydrolysis from the simple or conjugated proteins by the action of acids, alkalies or enzymes. They include two types of derivatives, primary-derived proteins and secondary-derived proteins. 

Selective alkylation of amino groups can be achieved by exposure of proteins, in alkaline solution, to low concentrations of formaldehyde and sodium borohydride. Both a- and e-amino groups are modified. e-N-Methyllysine, an e-N,N-dimethyllysine, may be readily quantitated after acid hydrolysis (see 2.12.1.2). The physical properties of the alkylated protein derivatives are very similar to those of the un-... 

The S-aminoethylcysteine content of the protein derivative can readily be determined following acid hydrolysis of the protein under the usual conditions, and amino acid analysis ( 2.5.4). 

The 4-thialaminine content of the protein derivative is determined by amino acid analysis after acid hydrolysis ( 2.5.6). 

L(+)-alanine, V-acetyl-, crystals, mp 116C. L(+)-alanine, V-benzoyl-, crystals, mp 152-154C. Derivation Hydrolysis of protein (silk, gelatin, zein), organic synthesis. 

Derivation Hydrolysis of protein degradation of cystine. Found in urinary calculi. 

Derivation Hydrolysis of protein (keratin), organic synthesis. Occurs as small hexagonal crystals in urine. 

Derivation Hydrolysis of vegetable protein (e.g., beet sugar waste, wheat gluten), organic synthesis based on acrylonitrile. It comprises 40% of the gliadin in wheat gluten. 

Derivation Hydrolysis of protein (gelatin), organic synthesis. 

Derivation Hydrolysis of protein (zein, edestin), animation of a-bromo-(i-methylvalenc acid. 

Derivation Hydrolysis of protein (edestin, hemoglobin, zein), organic synthesis from the a-bromo acid. 

Derivation Isolated from proteins after hydrolysis with alkali. 

Derivation Hydrolysis of proteins, synthesized by the reaction of ammonia with a-chloroisovaleric acid. Available commercially as D-, L-, or DL-valine. 

The secondary protein derivatives result from hydrolytic cleavage. As proteins yield a large number of amino-acids on complete hydrolysis, it is evident that they are built up by the combination of these acids as the result of the elimination of water. When a molecule so constituted is cautiously hydrolyzed,... 

Peptones are small polypeptides that are intermediate products in the hydrolysis of proteins. The term is often used for any partial hydrolysate of proteins, e.g., bacteriological peptone, which is used as a medium for the growth of microorganisms. Peptones are water-soluble protein derivatives obtained by the partial hydrolysis of a protein by an acid or enzyme during digestion. 

After acid hydrolysis of wool or proteins that have been treated with FDNB, the DNP derivatives of amino acids from the amino end of protein chains are soluble in ether, whereas amino acids whose side-chains have reacted only with FDNB together with unreacted amino acids are not soluble. Thus the amino acids from the amino ends of protein chains (amino-terminal amino acids) can be separated from other amino acids. The method is used to estimate the proportions of the different amino acids that occupy the amino-terminal positions of proteins in wool fibers and in proteins derived from wool. If peptide bond hydrolysis occurs... 

Definition Hydrolysate of corn protein derived by acid, enzyme or other hydrolysis Uses Antlstat, hair conditioner, skin conditioner in cosmetics, hair care, skin care Trade Name Synonyms Corn-Pro 35 t[Arch Personal Care Prods. 

Definition Hydrolysate of human placental protein derived by acid, enzyme, or other method of hydrolysis... 

Hydrolyzed oat protein Synonyms Oat protein, hydrolyzed Definition Hydrolysate of oat protein derived by acid, enzyme, or other method of hydrolysis Uses Antistat in cosmetics Trade Name Synonyms Aqua Pro II OP [Midwest Grain Prods. http //www.midwestgrain. com]... 

Definition Hydrolysate of rice protein derived by acid, enzyme, or other method of hydrolysis Uses Antistat, skin conditioner, hair conditioner, oil binder, film-former, moisturizer, anti-irritant in cosmetics, oil-absorbent formulations, hair care, skin care Features Bland substantive protein Manuf./Distrib. Tri-K Ind. http //www.tri-k.com Trade Name Synonyms Aqua Pro II RP [Midwest Grain Prods. http //www.midwestgrain.com]] Gluadin R [Cognis/Care Chems.] Hydrane R t[Alban Muller http //www.aibanmuiier.com]] Rice-Pro EN-20 [Arch Personal Care Prods. http //www.archchemicais.com]] Rice Pro-Tein BK [Maybrook Costec http //www.costec.com] Hydrolyzed RNA Synonyms RNA hydrolysate Definition Hydrolysate of RNA derived by acid, enzyme or other method of hydrolysis Uses Biological additive, skin conditioner, hair conditioner in cosmetics Trade Name Synonyms Lisato RNA [Variati]... 

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