Tryptic Hydrolysis Research Articles

Angiotensin-I-converting enzyme inhibitory peptides from tryptic hydrolysate of bovine α S2-casein

Angiotensin-I-converting enzyme (ACE) inhibitory activity of a tryptic digest of bovine α S2-casein (α S2-CN) was extensively investigated. Forty-three peptide peaks were isolated and tested. Seven casokinins (i.e. CN-derived ACE inhibitory peptides) were identified and their IC 50 values were determined. Four peptides exhibited an IC 50 value lower than 20 μM. Peptides α S2-CN (f174–181) and α S2-CN (f174–179) had IC 50 values of 4 μM. Surprisingly, deletion of the C-terminal dipeptide of two of these casokinins did not significantly alter their inhibitory activity.

Peptides From the N-terminal End of Bovine Lactoferrin Induce Apoptosis in Human Leukemic (HL-60) Cells

To determine the effects of the multifunctional iron-binding glycoprotein, lactoferrin (LF) and related compounds on the growth of leukemic cells, human myeloid leukemic cells (HL-60) were exposed to bovine lactoferrin (bLF) and proteolytic hydrolysates of bLF. Pepsin hydrolysates of bLF showed a greater growth suppressive effect than tryptic hydrolysates or mature bLF. Four peptides with proliferation inhibition activity were purified from pepsin hydrolysates by ion-exchange chromatography, reverse-phase HPLC, and gel-filtration. All peptides were from the N-terminal end, in a region where lactoferricin B (Lfcin B), an antibacterial peptide, is located. Among the four peptides, peptide 1 (pep1) was found to exhibit highest activity and corresponded to residues 17 to 38 of bLF, with a molecular weight of 2753.88. The IC50 value of this peptide was 6.3μg/ml. Three other peptides were less active and corresponded to sequences 1 to 16 and 45 to 48, linked by disulfide-bridge (pep2, molecular mass of 2430.13), 1 to 15 and 45 to 46 linked by disulfide bridge (pep3, molecular mass of 2017,92) and from residues 1 to 13 (pep4, molecular mass of 1558.73). Cell proliferation inhibition activity of the peptides was thought to be due to induction of apoptosis, which was evaluated by DNA ladder formation, DNA fragmentation, enhanced expression of phosphatidyl serine, and morphological changes. The IC50 values of the three peptides were confirmed using synthetic peptides and were consistent with those of purified peptides.

OSMONICS TO INVEST IN NEW RO FACILITY

The present work was undertaken in order to characterize the impact of fouling by a β-LG tryptic hydrolysate on the retention characteristics of a “loose” NF membrane. The influence of some physico-chemical (feed concentration, pH) as well as operating parameters (transmembrane pressure, feed velocity) on the ability of the G-10 membrane (Osmonics, Minnetonka, MN) with a molecular weight cut-off (MWCO) of 2500 g mol−1 to fractionate acid, neutral and basic peptides was first evaluated using a screening NF procedure. Preliminary electrolyte retention (NaCl, Na2SO4, CaCl2) measurements had shown that this NF membrane seems to exhibit Donnan exclusion mechanism typical of a negatively charged membrane. Complete retention of acid peptides was observed with the G-10 membrane at both pH 5 and 9. Separation between neutral and basic peptides was also achievable at pH 9 as compared to pH 5 due to the electrostatic repulsion of the neutral peptides that acquire a net negative at pH 9. The fractionation between neutral and basic peptides was optimal when the transmembrane pressure was raised to intermediate or higher values. The effect of fouling in these selected NF optimal conditions on the sieving and electrostatic properties of the G-10 was further studied by test solute retention methods. It was shown that an important hydraulic resistance due to fouling developed during NF of a 0.1% β-LG hydrolysate solution. At pH 5 and 9, the resulting sieving property of the G-10 membrane clearly depend on this fouled peptidic layer. Furthermore, the net negative charge of the membrane seemed to be reduced only after fouling at pH 9. It was thus suggested that the composition of the peptide layer interacting with the G-10 membrane and causing fouling is pH-dependent.

Thermal modifications of structure and co-denaturation of alpha-lactalbumin and beta-lactoglobulin induce changes of solubility and susceptibility to proteases.

Study of heat denaturation of major whey proteins (beta-lactoglobulin or alpha-lactalbumin) either in separated purified forms, or in forms present in fresh industrial whey or in recomposed mixture respecting whey proportions, indicated significant differences in their denaturation depending on pH, temperature of heating, presence or absence of other codenaturation partner, and of existence of a previous thermal pretreatment (industrial whey). alpha-Lactalbumin, usually resistant to tryptic hydrolysis, aggregated after heating at > or = 85 degrees C. After its denaturation, alpha-lactalbumin was susceptible to tryptic hydrolysis probably because of exposure of its previously hidden tryptic cleavage sites (Lys-X and Arg-X bonds). Heating over 85 degrees C of beta-lactoglobulin increased its aggregation and exposure of its peptic cleavage sites. The co-denaturation of alpha-lactalbumin with beta-lactoglobulin increased their aggregation and resulted in complete exposure of beta-lactoglobulin peptic cleavage sites and partial unveiling of alpha-lactalbumin tryptic cleavage sites. The exposure of alpha-lactalbumin tryptic cleavage sites was slightly enhanced when the alpha-lactalbumin/beta-lactoglobulin mixture was heated at pH 7.5. Co-denaturation of fresh whey by heating at 95 degrees C and pH 4.5 and above produced aggregates stabilized mostly by covalent disulfide bonds easily reduced by beta-mercaptoethanol. The aggregates stabilized by covalent bonds other than disulfide arose from a same thermal treatment but performed at pH 3.5. Thermal treatment of whey at pH 7.5 considerably enhanced tryptic and peptic hydrolysis of both major proteins.

Antigenotoxicity of peptides produced from silk fibroin

This study was conducted to examine in vitro antigenotoxic effects of the peptides derived from the hydrolysates of silk fibroin in mouse embryo 3T3 cells. The hydrolysates were prepared by acid or enzymic hydrolysis of fibroin, and antigenotoxicities were determined by measuring the reduced levels of DNA damage using the Comet assay. The fibroin preparation isolated from cocoons was efficiently digested by hydrolytic reactions with acid or Alcalase, an industrial protease. The acid- and Alcalase hydrolysates showed higher antigenotoxic activities than peptic- and tryptic hydrolysates. Active peptide fractions were separated from acid- and Alcalase hydrolysate by gel filtration chromatography. It was deduced from the chromatograms and amino acid analyses that the size (3–7 amino acids) and the glycine plus alanine content of peptides might be important factors for their activities. In addition, it was found that the antigenotoxic effect of peptides was due both to the protective interactions between cells and peptide molecules and to the direct inactivation of the mutagen, MNNG by peptides. Considering the availability and safety of silk fibroin and the superior antigenotoxic effects of produced peptides, the results of this study showed the possibility of utilizing fibroin as a source for chemopreventive functional peptides.

Heat-resistant structural features of bovine β-lactoglobulin A revealed by NMR H/D exchange observations

The thermal unfolding of the A variant of bovine β-lactoglobulin (β-Lg), in 50 mm phosphate buffer at pH 3.0, was followed by nuclear magnetic resonance (NMR) hydrogen/deuterium (H/D) exchange observations. The exchange behaviour of a large number of backbone amide protons (HNs) was monitored at temperatures between 37°C and 80°C to determine the relative thermal stability of different elements of the native protein structure. The H/D exchange was rapid at 37°C for the HNs on the residues in loops and in the terminal regions of the native protein. Further H/D exchange was promoted by heat treatment at temperatures up to 80°C and was completed for the identifiable HN of the various α and β structural elements in the following order: D–E strand (55–60°C); C–D strand and α-helix (60–65°C); A–B, A–I and E–F strands (65–70°C); and A–H, B–C and F–G strands (75–80°C). At 80°C, the only identifiable HN signal was from F105 which indicated that the G–H pair of disulphide-linked strands formed the most heat-resistant feature of the β-Lg structure. The effect of heating to 80°C was shown to be largely reversible by subsequent D/H exchange and sodium dodecyl sulphate polyacrylamide gel electrophoresis. Interestingly, the susceptibility of particular HNs to H/D exchange was found to correlate reasonably well with the susceptibility to tryptic hydrolysis.

Fractionation of beta-lactoglobulin tryptic peptides by ampholyte-free isoelectric focusing.

Solutions of tryptic hydrolysate of bovine beta-lactoglobulin were fractionated by liquid-phase IEF in a preparative Rotofor cell at constant power for 2 h without ampholytes in order to identify interactions between peptides. The 20 peptide fractions collected were analyzed by capillary electrophoresis and SDS-PAGE under native, denaturing, and reducing conditions. The hydrolysate was shown to be composed mainly of acidic peptides (pI 2-5, 62%) of molecular mass below 6 kDa, and numerous disulfide bonds were detected. Purified peptides (beta-LG 15-20, 71-75, 76-82, and 84-91) were also focused individually and in mixtures and matched to components of the IEF fractions obtained from the tryptic hydrolysate of beta-LG. The separation of acidic (beta-LG 84-91) and basic (beta-LG 76-82) peptides was achieved by IEF, whereas uncharged peptides (beta-LG 15-20 and 71-75) were poorly separated due to their low electrophoretic mobility. Because no peptide-peptide interaction could be identified by IEF fractionation, it is suggested that electrical fields may decrease electrostatic interactions between charged peptides.

Slow Folding of Three-Fingered Toxins Is Associated with the Accumulation of Native Disulfide-Bonded Intermediates

Snake neurotoxins are short all-beta proteins that display a complex organization of the disulfide bonds: two bonds connect consecutive cysteine residues (C43-C54, C55-C60), and two bonds intersect when bridging (C3-C24, C17-C41) to form a particular structure classified as "disulfide beta-cross". We investigated the oxidative folding of a neurotoxin variant, named alpha62, to define the chemical nature of the three-disulfide intermediates that accumulate during the process in order to describe in detail its folding pathway. These folding intermediates were separated by reverse-phase HPLC, and their disulfide bonds were identified using a combination of tryptic hydrolysis, manual Edman degradation, and mass spectrometry. Two dominant intermediates containing three native disulfide bonds were identified, lacking the C43-C54 and C17-C41 pairing and therefore named des-[43-54] and des-[17-41], respectively. Both species were individually allowed to reoxidize under folding conditions, showing that des-[17-41] was a fast-forming nonproductive intermediate that had to interconvert into the des-[43-54] isomer before forming the native protein. Conversely, the des-[43-54] intermediate appeared to be the immediate precursor of the oxidized neurotoxin. A kinetic model for the folding of neurotoxin alpha62 which fits with the observed time-course accumulation of des-[17-41] and des-[43-54] is proposed. The effect of turn 2, located between residues 17 and 24, on the overall kinetics is discussed in view of this model.

Reflections about the functional potential of legume proteins. A review.

The term "functional potential" was introduced to better approach to the understanding of the relationships between the structure and the functional properties of food proteins. Although in practice the complex of structural features of a protein contributes to its functionality, it is very useful to regard the functional potential of the protein surface on the one side and to look on special effects of protein conformation (role of compact or unfolded state) on the functionality on the other side. This point of view may help to design the best strategy of modification of the protein structure and functionality. The special situation of the oligomeric legume storage protein, i.e. legumin-like 11 S globulins and vicilin-like 7 S globulin, and the structural and functional modification of 11 S globulin by limited tryptic hydrolysis and by acylation are discussed in this paper.

Debittering and Hydrolysis of a Tryptic Hydrolysate of β‐casein with Purified General and Proline Specific Aminopeptidases from Lactococcus lactis ssp. cremoris AM2

ABSTRACT: In this study, purified β‐casein was hydrolysed with trypsin to produce a bitter substrate. The role of 3 aminopeptidases, a general aminopeptidase lysyl‐para‐nitroanilide hydrolase (KpNA‐H), X‐prolyl dipeptidyl aminopeptidase (Pep X) and aminopeptidase P (Pep P) each purified from Lactococcus lactis ssp. cremoris AM2, in the hydrolysis and debittering of the tryptic hydrolysate of β‐casein, was then studied. The hydrolysates were analyzed for percentage degree of hydrolysis (DH%) and bitterness score. Results indicate that the hydrolysis and debittering potential of the general aminopeptidase (KpNA‐H) is limited in the absence of proline specific aminopeptidases. Statistically significant (p < 0.001) reductions in bitterness were obtained following incubation of the tryptic digest of β‐casein with specific combinations of the above aminopeptidases.

Characterization of alpha-casozepine, a tryptic peptide from bovine alpha(s1)-casein with benzodiazepine-like activity.

Caseins are a known source of biologically active peptides. In this study, we have shown evidence of a novel anxiolytic activity in a tryptic hydrolysate of bovine α s1-casein. Injection of 3 mg/kg of this hydrolysate significantly reduced the epileptic symptoms caused by pentylenetetrazole in rats. Anxiety reduction was also observed when the hydrolysate was tested in the elevated plus-maze and in the conditioned defensive burying rat models. Peptides isolated from the hydrolysate were examined for their affinity for the γ-amino-butyric acid (GABA) type A receptor. Only one peptide, named α -casozepine, corresponding to the 91–100 fragment from bovine α s1-casein, expressed affinity for GABA A receptor. In vitro, the peptide had 10,000 less affinity for the benzodiazepine site of the GABA A than did diazepam. However, in the conditioned defensive burying paradigm it was 10-fold more efficient than diazepam. The difference observed between the in vitro and in vivo activity of α -casozepine could not been explained by an action via the peripheral-type benzodiazepine receptor; α -casozepine had no affinity for this receptor. The α -casozepine amino acid sequence could be related to the carboxyterminal sequence of the polypeptide diazepam binding inhibitor, an endogenous ligand of the central GABAA and peripheral-type benzodiazepine receptors.

200 mg of Zen: L-Theanine Boosts Alpha Waves, Promotes Alert Relaxation

Alternative and Complementary TherapiesVol. 7, No. 2 Articles200 mg of Zen: L-Theanine Boosts Alpha Waves, Promotes Alert RelaxationRuss MasonRuss MasonSearch for more papers by this authorPublished Online:5 Jul 2004https://doi.org/10.1089/10762800151125092AboutSectionsPDF/EPUB ToolsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail FiguresReferencesRelatedDetailsCited byEffect of Alpha-S1-Casein Tryptic Hydrolysate and L-Theanine on Poor Sleep Quality: A Double Blind, Randomized Placebo-Controlled Crossover Trial3 February 2022 | Nutrients, Vol. 14, No. 3The Interventions for Sleep Disorders in Children with Attention Deficit and Hyperactivity Disorder: A Narrative Review25 November 2021 | Open Access Macedonian Journal of Medical Sciences, Vol. 9, No. T6Effect of Green Tea Amino Acid L-Theanine on Physiological Responses: A Protocol for Clinical Trial14 August 2020 | Exploratory Research and Hypothesis in Medicine, Vol. 000, No. 000Enzymatic synthesis of L-theanine from L-glutamine and ethylamine by Bacillus licheniformis γ-glutamyltranspeptidase and its mutants specialized in transpeptidase activityBiocatalysis and Agricultural Biotechnology, Vol. 22Nutrients, Energy Values and Health Impact of Conventional BeveragesRecent Trends in Drug Discovery against Alzheimer's Disease: Use of Natural Products and Nutraceuticals from Botanicals28 December 2018Effect of Green Tea Phytochemicals on Mood and CognitionCurrent Pharmaceutical Design, Vol. 23, No. 19Effects of Camellia Sinensis Extract on Passive Avoidance Learning and Hippocampal Neurogenesis in Rats11 August 2017 | Neurophysiology, Vol. 49, No. 2l-Theanine as a Functional Food Additive: Its Role in Disease Prevention and Health Promotion30 May 2016 | Beverages, Vol. 2, No. 2In Search of a Safe Natural Sleep Aid11 March 2015 | Journal of the American College of Nutrition, Vol. 34, No. 5Neuroprotective activity of L -theanine on 3-nitropropionic acid-induced neurotoxicity in rat striatum23 January 2014 | International Journal of Neuroscience, Vol. 124, No. 9Epidemiological Evidence Linking Tea Consumption to Human Health: A Review15 November 2013 | Critical Reviews in Food Science and Nutrition, Vol. 54, No. 4L-Theanine: properties, synthesis and isolation from tea29 March 2011 | Journal of the Science of Food and Agriculture, Vol. 91, No. 11Effects of l-theanine on attention and reaction time responseJournal of Functional Foods, Vol. 3, No. 3Is a Neuroprotective Therapy Suitable for Schizophrenia Patients?19 February 2010Chemistry and Biological Properties of Theanine11 January 2010Green Tea Catechins and L-Theanine in Integrative Cancer Care: A Review of the Research Luke G. Huber5 July 2004 | Alternative and Complementary Therapies, Vol. 9, No. 6 Volume 7Issue 2Apr 2001 To cite this article:Russ Mason.200 mg of Zen: L-Theanine Boosts Alpha Waves, Promotes Alert Relaxation.Alternative and Complementary Therapies.Apr 2001.91-95.http://doi.org/10.1089/10762800151125092Published in Volume: 7 Issue 2: July 5, 2004PDF download

Susceptibility to trypsinolysis of esterified milk proteins

Methyl-, ethyl- and propyl-esters of β-lactoglobulin, α-lactalbumin and β-casein were prepared and then hydrolyzed with trypsin in various conditions. Resulting hydrolysates were analysed by SDS electrophoresis and RP-HPLC. The degree of hydrolysis of esterified samples was generally lower than those of the non-modified proteins. The highest degrees of hydrolysis were obtained at pH 7–8 with native and esterified protein samples. β-Lactoglobulin propyl ester and β-casein methyl ester yielded the lowest degrees of hydrolysis. Ethyl- and propyl-esters of β-casein showed high resistance towards tryptic attack, even after 20 h of hydrolysis. SDS electrophoretic patterns of tryptic hydrolysates of native proteins showed bands corresponding to low molecular weights. Tryptic hydrolysates of esterified proteins showed bands with higher sizes. RP-HPLC profiles of tryptic hydrolysates of esterified samples showed peaks with longer elution times than those obtained with native proteins, indicating the presence of more hydrophobic peptide populations. A peptic pre-treatment improved tryptic action on esterified proteins. It resulted in a better resolution of RP-HPLC profiles and in a complete disappearance of the protein after 20 h tryptic hydrolysis.

Improved storage stability of model infant formula by whey peptides fractions.

The purpose of this study was to evaluate the shelf-life stability (6 months) of model infant formula with whey protein hydrolysates or peptidic fractions as carrageenan replacers. Whey protein hydrolysates were prepared with trypsin and followed by ultrafiltration of the hydrolyzed mixture, and peptidic fractions were isolated from the ultrafiltered tryptic hydrolysate by anion- or cation-exchange chromatography. The stability of the model infant formula was evaluated using a stratification method based on fat content differences between the top and bottom strata of the samples. With protein hydrolysate-based formulations, the creaming rate of the fat in the product was slightly higher than in the standard formulation (with carrageenan), which is indicative of lower storage stability. The addition of cationic fractions to model infant formula also resulted in lower product stability, whereas the fat creaming rate was retarded in anionic fraction based formulations. The physicochemical characteristics of certain peptides combined with the reported high emulsifying properties of peptidic sequences found within these fractions may account for their ability to act as carrageenan replacers.

Tryptic hydrolysis of hGH‐RH(1‐29)‐NH2 analogues containing Lys or Orn in positions 12 and 21

Tryptic hydrolysis of hGH‐RH(1‐29)‐NH2 analogues containing Lys or Orn in positions 12 and 21

Identification of Novel Hypocholesterolemic Peptides Derived from Bovine Milk β-Lactoglobulin

This study was designed to clarify the mechanisms of hypocholesterolemic action of β-lactoglobuline tryptic hydrolysate (LTH) and to identify the novel hypocholesterolemic peptide derived from LTH by screening using Caco-2 cells and animal studies. Serum and liver cholesterol levels were significantly lower in rats fed LTH than in those fed casein tryptic hydrolysate (CTH). The present study suggests that the inhibition of micellar solubility of cholesterol which causes the suppression of cholesterol absorption by a direct interaction between cholesterol mixed micelles, and LTH in the jejunal epithelia is part of the mechanism underlying the hypocholesterolemic action of LTH. Though no one could trace the hypocholesterolemic peptide to any protein origin, we identified, for the first time, a novel hypocholesterolemic peptide, Ile-Ile-Ala-Glu-Lys (IIAEK). Surprisingly, the present study provides the first direct evidence that a new hypocholesterolemic peptide derived from β-lactoglobuline can powerfully influence serum cholesterol levels and exhibit a greater hypocholesterolemic activity in comparison with that of medicine, β-sitosterol, in animal studies.

CHARACTERIZATION OF THE MAILLARD REACTION PRODUCTS OF ?-LACTOGLOBULIN GLUCOSYLATED IN MILD CONDITIONS

beta-Lactoglobulin (BLG) was heated in the presence of glucose in mild conditions leading to nonenzymatic glycation through the Maillard reaction. The characterization of the chromophores formed during heating at 60C showed that the modification of the UV-VIS spectrum of modified proteins was mainly due to a condensation reaction of glucose. Amino acid analysis showed that at least four amino acids (lysine, arginine, histidine and tyrosine) were modified during the reaction. Modification of SDS-PAGE pattern indicated the prevalence of a covalent polymerization of the BLG monomers independent from disulfide bridge formation. Solubility of the glucose-beta-lactoglobulin conjugates was higher than that of heated protein at pH 5. A shift of the minimum of solubility toward acidic pH, relative to the shift of the pI of modified proteins, was observed as a function of time of glycation. Tryptic hydrolysis of the modified proteins revealed a slow glycation of Lys 69 as compared to Lys 70, which is consistent with its three-dimensional orientation and its potential biological role.

Limited tryptic hydrolysis of pea legumin: molecular mass and conformational stability of legumin-T

The investigation of hydrodynamic and thermodynamic properties and the determination of the molecular mass of legumin-T, the product of limited tryptic hydrolysis of the 11-S-globulin from pea seeds, was carried out to ascertain the structural relationship to globulin-T's from other legumin-like proteins. The obtained legumin-T preparation has a molecular mass M W=260±10 kDa and M S,D=270±20 kDa. The secondary structure of legumin-T is characterised by a high percentage of β-sheet conformation, comparable to that of native legumin and a reduced percentage of helical conformation. The conformational stability of legumin-T evaluated by equilibrium unfolding in the presence of guanidinium chloride was only slightly reduced in comparison to the native legumin, whereas the calorimetrically determined denaturation enthalpy and Gibbs energy of denaturation were found to be increased for legumin-T. These physicochemical properties are very similar to those of faba bean legumin-T.

Bilirubin binding to normal and modified human erythrocyte membranes: effect of phospholipases, neuraminidase, trypsin and CaCl2.

Binding of bilirubin to human erythrocyte membranes was studied after various enzymatic treatments as well as calcium loading. Whereas phospholipase D treatment of erythrocyte membranes resulted in 23% increase in bilirubin binding, phospholipase C-treated membranes showed remarkable enhancement in bilirubin binding. Polar head groups in general and negatively charged phosphate moieties, in particular, of phospholipids of the membrane appear to inhibit a large amount of bilirubin from binding to the membranes. Neuraminidase treatment of the membranes also led to a slight increase in bilirubin binding as compared to untreated membranes. Membrane proteins and carbohydrates seem to play significant regulatory role in bilirubin binding. However, no direct correlation was found between the increase in bilirubin binding and the amount of carbohydrate released upon tryptic digestion of membranes. Increase in bilirubin binding to trypsin-treated membranes can be ascribed to the increase in free bilirubin concentration in the incubation mixture as a result of tryptic hydrolysis of albumin by the membrane-bound tryptic activity. Calcium-loaded erythrocyte membranes also showed remarkable increase in bilirubin binding as a result of negative charge shielding and calcium-induced hydrophobic aggregation. Taken together, these results suggest the inhibitory role of polar head groups of phospholipids (phosphate in particular), carbohydrate and sialic acid in the binding of bilirubin to erythrocyte membranes.

Efeito da adição de NaCl sobre as propriedades funcionais do plasma bovino e de seus hidrolisados trípticos

O efeito da adicao de NaCl, numa concentracao de0,035 mol/L, sobre algumas propriedades funcionais do plasma e de seus hidrolisados tripticos foi estudado em dois valores de pH (5,0 e 6,0). Foram determinados a solubilidade proteica, a hidrofobicidade, a capacidade emulsionante (EC), o indice de atividade emulsionante (EAI) e a estabilidade da emulsao (ES). Os resultados obtidos indicam que, nos dois valores de pH estudados, a adicao de NaCl levou a uma reducao significativa da solubilidade, da hidrofobicidade e da EC do plasma, e de alguns de seus hidrolisados tripticos. Por outro lado, aumentou os valores de EAI do plasma, no pH 5,0 assim como da maioria de seus hidrolisados tripticos. Com relacao a ES, este tratamento nao exerceu qualquer influencia sobre o plasma, tendo, entretanto, afetado positivamente alguns hidrolisados tripticos, especialmente no pH 5,0.