Proteinase and exopeptidase hydrolysis of whey protein: Comparison of the TNBS, OPA and pH stat methods for quantification of degree of hydrolysis

2003 ◽  
Vol 13 (6) ◽  
pp. 447-453 ◽  
Author(s):  
D. Spellman ◽  
E. McEvoy ◽  
G. O’Cuinn ◽  
R.J. FitzGerald
Keyword(s):  
Whey Protein ◽  
Degree Of Hydrolysis ◽  
Ph Stat ◽  
Hydrolysis Of

Research on Enzymatic Hydrolysis of Whey Protein

2013 ◽  
Vol 411-414 ◽  
pp. 3205-3209
Author(s):  
Fang Qian ◽  
Lei Zhao ◽  
Shu Juan Jiang ◽  
Guang Qing Mu
Keyword(s):  
Enzymatic Hydrolysis ◽  
Whey Protein ◽  
Degree Of Hydrolysis ◽  
Quadratic Regression ◽  
Orthogonal Regression ◽  
Single Factor Analysis ◽  
Verification Test ◽  
Enzyme Dosage ◽  
Hydrolysis Conditions ◽  
Hydrolysis Of

Based on single factor analysis for the enzymatic hydrolysis of whey protein, papain was selected as the optimal enzyme and its enzymatic hydrolysis conditions were optimized by the quadratic regression orthogonal rotary test. The orthogonal regression model for degree of hydrolysis (DH) to three factors including temperature (X1), time (X2), enzyme dosage (X3) was established as follow: DH=10.40+0.22X1+0.30X2+1.31X3+0.019X1X2+0.011X1X3-0.039X2X3-0.39X12-0.16X22-0.40X32, Verification test showed a DH of 11.7% was obtained at the optimal hydrolysis condition of 56.6°C, 113.8 min and enzyme 8213.7 U /g protein, which basically consisted with the model theoretical value.

Optimization of Multi-Enzyme Hydrolysis Process for Efficient Corn Gluten Meal Hydrolysis

2012 ◽  
Vol 608-609 ◽  
pp. 333-338
Author(s):  
Yuan Xiu Wang ◽  
Ming Yang Zheng ◽  
Xiao Hong Yang ◽  
Na Xin Sun ◽  
Gui Xiang Zhang
Keyword(s):  
Enzyme Hydrolysis ◽  
Degree Of Hydrolysis ◽  
Corn Gluten Meal ◽  
Optimal Ratio ◽  
Hydrolysis Process ◽  
Corn Gluten ◽  
Ph Stat ◽  
Stat Method ◽  
Hydrolysis Of ◽  
Single Enzyme

In order to hydrolyze corn gluten meal efficiently, combinations of two or three out of three hydrolysis enzymes (protex6L, protex7L and papain) were used and the process parameters were optimized in this paper. The degree of hydrolysis of corn gluten meal was assayed by using pH-stat method. The ratio of enzymes was optimized and the effect of multi-enzyme hydrolysis was compared with that of single-enzyme hydrolysis. The result showed that the optimal ratio of protex6L and protex7L was 3:1, protex6L and papain was 6:5, protex7L and papain was 1:1, and the optimal ratio of protex6L, protex7L and papain was 4:1:1.The degree of hydrolysis and soluble protein content of multi-enzyme hydrolysis and single-enzyme hydrolysis were approximately equal, but multi-enzyme hydrolysis was timesaving.

scholarly journals Effect of degree of hydrolysis of whey protein on in vivo plasma amino acid appearance in humans

SpringerPlus ◽  
2016 ◽  
Vol 5 (1) ◽  
Author(s):  
Jean Farup ◽  
Stine Klejs Rahbek ◽  
Adam C. Storm ◽  
Søren Klitgaard ◽  
Henry Jørgensen ◽  
...  
Keyword(s):  
Amino Acid ◽  
Whey Protein ◽  
Plasma Amino Acid ◽  
Degree Of Hydrolysis ◽  
Hydrolysis Of

scholarly journals Methodology for Determining Degree of Hydrolysis of Proteins in Hydrolysates: A Review

2010 ◽  
Vol 93 (5) ◽  
pp. 1515-1522 ◽  
Author(s):  
Shane M Rutherfurd
Keyword(s):  
Protein Hydrolysate ◽  
Hydrolytic Enzymes ◽  
Degree Of Hydrolysis ◽  
Soluble Nitrogen ◽  
Trinitrobenzenesulfonic Acid ◽  
Peptide Bonds ◽  
Ph Stat ◽  
Terminal Amino ◽  
Stat Method ◽  
Hydrolysis Of

Abstract Degree of hydrolysis (DH) is defined as the proportion of cleaved peptide bonds in a protein hydrolysate. Several methods exist for determining DH; the most commonly used of these include the pH-stat, trinitrobenzenesulfonic acid (TNBS), o-phthaldialdehyde (OPA), trichloroacetic acid soluble nitrogen (SN-TCA), and formol titration methods. The pH-stat method is based on the number of protons released during hydrolysis; the TNBS, OPA, and formol titration methods are based on the measurement of amino groups generated from hydrolysis. The SN-TCA method measures the amount of TCA-soluble nitrogen, rather than DH. The pH-stat is the simplest and most commonly used method, but does not determine peptide bonds directly. In addition, the accuracy of the method depends on the type of hydrolytic enzymes used, the size of the hydrolyzed peptides, and the reaction temperature. Generally, the TNBS and OPA methods compare well and do directly determine DH. However, the assumption that the response factor for all derivatized N-terminal amino acids is similar may lead to inaccuracies. In conclusion, there is no consensus as to the best method for determining the DH of protein hydrolysates; consequently, there is a need for a standardized approach if interstudy comparisons are to be made.

Polarographic study of hydrolysis of [8-lysine]vasopressin and its derivatives with blood serum of pregnant women

1980 ◽  
Vol 45 (4) ◽  
pp. 1099-1108 ◽  
Author(s):  
Mikuláš Chavko ◽  
Michal Bartík ◽  
Evžen Kasafírek
Keyword(s):  
Blood Serum ◽  
Pregnant Women ◽  
Degree Of Hydrolysis ◽  
Polarographic Study ◽  
Ph Optimum ◽  
Lysine Vasopressin ◽  
Rate Of Hydrolysis ◽  
Hydrolysis Of ◽  
Vasopressin Analogues

A polarographic study of the hydrolysis of [8-lysine]vasopressin and some hormonogens of the vasopressin series with the blood serum of women in the last week of pregnancy was studied. The dependence of hydrolysis on pH (pH optimum: 7.4-7.50, substrate concentration (Km 1.2 . 10-5M), pH stability and thermal stability were determined. The rate of hydrolysis of individual vasopressin analogues decreases in the order: [8-lysine]vasopressin > Nα-glycyl-prolyl[8-lysine]-vasopressin > Nα-leucyl-[8-lysine]vasopressin > Nα-alanyl-[8-lysine]vasopressin > Nα-phenyl alanyl-[8-lysine]vasopressin > Nα-diglycyl-[8-lysine]vasopressin > Nα-prolyl-[8-lysine]vasopressin > Nα-triglycyl-[8-lysine]vasopressin > Nα-sarcosyl-glycyl-[8-lysine]vasopressin. The degree of hydrolysis gradually increases to a multiple with the length of the pregnancy in consequence of the presence of oxytocine. However, vasopressin is also hydrolysed to a small extent with the enzymes from the blood sera of non-pregnant women. Under similar analytical conditions oxytocin was not hydrolysed with the sera of non-pregnant women and therefore oxytocin is a more suitable substrate than vasopressin for polarographic determination of serum oxytocinase.

scholarly journals Effect of Neutrase, Alcalase, and Papain Hydrolysis of Whey Protein Concentrates on Iron Uptake by Caco-2 Cells

2010 ◽  
Vol 58 (8) ◽  
pp. 4894-4900 ◽  
Author(s):  
Keqin Ou ◽  
Yunzhu Liu ◽  
Liebing Zhang ◽  
Xiaoguang Yang ◽  
Zhenwu Huang ◽  
...  
Keyword(s):  
Whey Protein ◽  
Iron Uptake ◽  
Protein Concentrates ◽  
Whey Protein Concentrates ◽  
Hydrolysis Of

scholarly journals Preparation of Antioxidant Enzymatic Hydrolysates from Honeybee-Collected Pollen Using Plant Enzymes

2010 ◽  
Vol 2010 ◽  
pp. 1-5 ◽  
Author(s):  
Margarita D. Marinova ◽  
Bozhidar P. Tchorbanov
Keyword(s):  
Radical Scavenging ◽  
Total Phenolic ◽  
Degree Of Hydrolysis ◽  
Enzymatic Hydrolysates ◽  
Phenolic Contents ◽  
Scavenging Capacity ◽  
Plant Enzymes ◽  
Hydrolysis Of ◽  
Proline Iminopeptidase ◽  
Dietary Food

Enzymatic hydrolysates of honeybee-collected pollen were prepared using food-grade proteinase and aminopeptidases entirely of plant origin. Bromelain from pineapple stem was applied (8 mAU/g substrate) in the first hydrolysis stage. Aminopeptidase (0.05 U/g substrate) and proline iminopeptidase (0.03 U/g substrate) from cabbage leaves (Brassica oleracea var. capitata), and aminopeptidase (0.2 U/g substrate) from chick-pea cotyledons (Cicer arietinum L.) were involved in the additional hydrolysis of the peptide mixtures. The degree of hydrolysis (DH), total phenolic contents, and protein contents of these hydrolysates were as follows: DH (about 20–28%), total phenolics (15.3–27.2 μg/mg sample powder), and proteins (162.7–242.8 μg/mg sample powder), respectively. The hydrolysates possessed high antiradical scavenging activity determined with DPPH (42–46% inhibition). The prepared hydrolysates of bee-collected flower pollen may be regarded as effective natural and functional dietary food supplements due to their remarkable content of polyphenol substances and significant radical-scavenging capacity with special regard to their nutritional-physiological implications.

scholarly journals THE INFLUENCE OF AMMONIUM SALTS ON CELL REACTION

1922 ◽  
Vol 5 (2) ◽  
pp. 181-188 ◽  
Author(s):  
M. H. Jacobs
Keyword(s):  
Organic Acids ◽  
Neutral Red ◽  
Living Cells ◽  
Ammonium Salts ◽  
Degree Of Hydrolysis ◽  
Cell Reaction ◽  
Artificial Cell ◽  
Acid Reaction ◽  
Hydrolysis Of

1. It may be shown by means of cells of the flowers of a hybrid Rhododendron which contain a natural indicator, by means of starfish eggs stained with neutral red, and by means of an "artificial cell" in which living frog's skin is employed that increased intracellular alkalinity may be brought about by solutions of a decidedly acid reaction which contain ammonium salts. 2. These results are analogous to those previously obtained with the CO2-bicarbonate system, and depend on the facts: (a) that NH4OH is sufficiently weak as a base to permit a certain degree of hydrolysis of its salts; and (b) that living cells are freely permeable to NH4OH (or NH3?) and not to mineral and many organic acids, and presumably not at least to the same extent to ammonium salts as such.

Sign in / Sign up

Export Citation Format

Share Document