SUSCEPTIBILITY OF PROTEINS USED IN CALF MILK REPLACERS TO HYDROLYSIS BY VARIOUS PROTEOLYTIC ENZYMES

1980 ◽  
Vol 60 (4) ◽  
pp. 907-914 ◽  
Author(s):  
K. J. JENKINS ◽  
S. MAHADEVAN ◽  
D. B. EMMONS
Keyword(s):  
Trichloroacetic Acid ◽  
Proteolytic Enzymes ◽  
Milk Proteins ◽  
In Vitro Study ◽  
Enzyme Treatment ◽  
Protein Hydrolysis ◽  
Protein Substrates ◽  
Optimum Ph ◽  
Milk Replacers

An in vitro study was conducted to assess the hydrolytic susceptibility of various milk and non-milk proteins (soybean, rapeseed, fish) used in calf milk replacers to endogenous and commercial proteolytic enzymes. Extent of protein hydrolysis (%) was calculated from the reduced amount of protein precipitated by 10% trichloroacetic acid following enzyme treatment. All of the enzymes tested hydrolyzed the milk proteins more extensively than the non-milk proteins both at their optimum pH, and at the pH (6.1) of calf abomasal contents immediately after feeding. At both optimum pH and pH 6.1, the highest average hydrolysis value for all protein substrates was obtained with pronase followed by papain, trypsin, pancreatin, chymotrypsin, Mucor miehei rennet andchymosin (calf rennet). All substrates were hydrolyzed extensively by pepsin at pH 2.0 but, as expected, very little hydrolysis occurred with this enzyme atpH6.1.

Adult 175 kDa collagenase antigen ofSetaria cerviin immunoprophylaxis againstBrugia malayiin jirds

2004 ◽  
Vol 78 (4) ◽  
pp. 347-352 ◽  
Author(s):  
Y. Srivastava ◽  
S. Rathaur ◽  
Y.P. Bhandari ◽  
M.V.R. Reddy ◽  
B.C. Harinath
Keyword(s):  
Meriones Unguiculatus ◽  
Host Cells ◽  
Specific Substrate ◽  
Collagenase Activity ◽  
Setaria Cervi ◽  
Protein Substrates ◽  
Infective Larvae ◽  
Optimum Ph

AbstractA 175 kDa antigen fraction with collagenase activity was isolated and purified from somatic extracts of adultSetaria cervifemales using column chromatography involving consecutive steps of DEAE-Sepharose CL6B and Sephadex G-100. The optimum pH for 175 kDa collagenase was found to be pH 7.0. Sensitivities to a variety of inhibitors and activators indicated that the 175 kDa coIlagenolytic enzyme was metalloserine in nature. The enzyme hydrolysed a variety of protein substrates such as haemoglobin, casein, azocasein (general substrates) and collagen, FALGPA (furanoyl-acryloyl-leu-gly-pro-ala), the specific substrate of collagenase. The enzyme showed 57% inhibition by jird anti-somatic collagenase antibodies and reacted insignificantly with normal jird sera. Further analysis was undertaken on the immunoprophylactic potential of 175 kDa collagenase in inducing immunity againstBrugia malayi(a human filarial parasite) in jirds (Meriones unguiculatus)in vitroandin situ. Immune sera of jirds raised against this antigen promoted partial adherence of peritoneal exudate cells toB. malayimicrofilariae (mf) and infective larvae (L3)in vitroand induced partial cytotoxicity to the parasites within 48 h. The anti-S. cervi175 kDa antigen serum was more effective in inducing cytotoxicity toB. malayiL3, than mf. In the microchambers implanted inside immune jirds, host cells could migrate and adhere to the mf and infective larvae thereby killing them partially within 48 h.

Modification of the digestibility of extruded rice starch by enzyme treatment (β-amylolysis): An in vitro study

2018 ◽  
Vol 111 ◽  
pp. 590-596 ◽  
Author(s):  
Jiangping Ye ◽  
Chengmei Liu ◽  
Shunjing Luo ◽  
Xiuting Hu ◽  
David Julian McClements
Keyword(s):  
In Vitro Study ◽  
Vitro Study ◽  
Enzyme Treatment ◽  
Rice Starch

INTERACTION OF THROMBOLYTIC PROTEINASES COMPLEX LONGOLITIN AND ITS PRODUCER — MYCELIAL FUNGUS ARTHROBOTRYS LONGA — WITH ANTITHROMBOTIC DRUG PIYAVIT

2018 ◽  
Author(s):  
Т.С. Шаркова ◽  
И.Б. Павлова ◽  
Л.В. Подорольская
Keyword(s):  
Proteolytic Enzymes ◽  
In Vitro Study ◽  
Culture Liquid ◽  
Mycelial Fungus ◽  
Antithrombotic Agents ◽  
Antithrombotic Drug ◽  
Combined Application ◽  
Anamorphic Fungus ◽  
Intact Rats

Цель исследования: изучение взаимодействия комплекса протеолитических ферментов препарата лонголитин из анаморфного гриба Arthrobotrys longa с антикоагулянтным и антитромботическим препаратом пиявитом. Материалы и методы. Препарат пиявит смешивали в разных разведениях с различными концентрациями лонголитина и определяли фибринолитическую активность (ФА) смеси. В другой серии опытов пиявит добавляли в погруженную культуру гриба-продуцента. По окончании эксперимента в пробах культуральной жидкости (КЖ) определяли ФА. Антикоагулянтные свойства КЖ измеряли методом рекальцификации и записи тромбоэластограммы при добавлении КЖ к плазме крови здоровых интактных крыс. Результаты. В опытах in vitro пиявит дозозависимо угнетал ФА лонголитина до полного ее подавления при концентрации 16 мг/мл. Добавление пиявита к культуре гриба-продуцента вызывало усиление биосинтеза препарата с увеличением ФА. КЖ при этом обладала высокой антикоагулянтной активностью. Время рекальцификации и показатель R тромбоэластограммы в КЖ были статистически достоверно удлинены, увеличивалась и антиполимеризационная активность КЖ. Заключение. Совместное применение двух антитромботических средства (лонголитина и пиявита) в исследовании in vitro привело к уменьшению фибринолитических, а значит, и тромболитических свойств лонголитина. Таким образом, одновременное использование этих препаратов требует осторожности. Aim: to study the interaction of Longolitin (complex of proteolytic enzymes from anamorphic fungus Arthrobotrys longa) with anticoagulative and antithrombotic drug Piyavit. Materials and methods. We mixed diff erent dilutions of Piyavit with various concentrations of Longolitin and determined fibrinolytic activity (FA) of the mixture. In other experimental series we added Piyavit to submerged culture of the fungus-producer. At the end of the experiment we determined FA in culture liquid samples (CL). Anticoagulative properties of CL were measured by recalcification method and thromboelastograms recording with CL addition to blood plasma of healthy intact rats. Results. In in vitro experiments Piyavit dose-dependently inhibited FA of Longolitin until it’s completely suppression at concentration of 16 mg/ml. Piyavit addition to the culture of fungus-producer caused the enhancement of drug biosynthesis with FA increasing. At the same time CL had a high anticoagulative activity. Recalcifi cation time and parameter R of thromboelastogram in CL were statistically signifi cant elongated, also CL anti-polymerization activity increased. Conclusion. Combined application of two antithrombotic agents (Longolitin and Piyavit) in in vitro study led to decreasing of fibrinolytic, and so thrombolytic properties of Longolitine. Thus, the simultaneous use of these drugs requires caution. Adding piyavit to the culture of the producer fungus led to an increase in the biosynthesis of the preparation. Thus, caution is needed at simultaneous using of these drugs.

PANCREATIC LIPASE ACTIVITY IN RELATION TO HIGH LEVELS OF FAT IN CALF MILK REPLACERS

1979 ◽  
Vol 59 (2) ◽  
pp. 463-465
Author(s):  
K. J. JENKINS
Keyword(s):  
Small Intestine ◽  
Pancreatic Lipase ◽  
Lipase Activity ◽  
In Vitro Study ◽  
Low Ph ◽  
Milk Replacer ◽  
High Fat ◽  
Ph Values ◽  
Milk Replacers

An in vitro study indicated that pancreatic lipase (PL) can effectively hydrolyze and solubilize milk replacer fats under conditions simulating those in the small intestine. When PL was added to high fat milk replacers very little lipolysis occurred in vitro at the low pH values encountered in the calf abomasum.

EFFECTS OF VARIOUS HEAT AND pH TREATMENTS ON DIGESTIBILITY OF PROTEIN IN PEA PROTEIN CONCENTRATE (PISUM SATIVUM)

1976 ◽  
Vol 56 (3) ◽  
pp. 559-566 ◽  
Author(s):  
C. CHOW ◽  
J. M. BELL
Keyword(s):  
Amino Acid Content ◽  
Milk Proteins ◽  
In Vitro Digestion ◽  
Protein Concentrate ◽  
Pepsin Activity ◽  
Pea Protein ◽  
Alkali Hydrolysis ◽  
Milk Replacers ◽  
Hydrolysis Of

Pea protein concentrate (PPC) was subjected to various cooking and acid or alkali treatments in order to improve the digestibility of pea protein for use in calf milk replacers. Treatment effects were assessed by in vitro digestion with rennin, pepsin and calf abomasal fluids. Oven heating at 95–246 C for 5 min to 15 h or steam heating at 1.06 kg/cm2 for 4 h failed to improve digestibility. Treatment of PPC in an aqueous medium at pH values from 2 to 12 for 5 h at 37 C resulted in higher digestibility. A pH of 2.0 or 10.6 was most effective. Acid or alkali hydrolysis of PPC at 110 C for 4–5 h increased digestibility, but adversely affected amino acid content. Rennin was consistently less effective than pepsin or abomasal contents in digesting PPC. The pH of abomasal contents from young calves fed milk replacers may be too high for effective pepsin activity. These factors could account for the low digestibility of non-milk proteins by calves under 2 wk of age.

Partial characterization of proteolytic enzymes in different developmental stages of Ostertagia ostertagi

1993 ◽  
Vol 67 (4) ◽  
pp. 271-278 ◽  
Author(s):  
H. de Cock ◽  
D. P. Knox ◽  
E. Claerebout ◽  
D. C. de Graaf
Keyword(s):  
Proteinase Inhibitor ◽  
Developmental Stages ◽  
Proteolytic Enzymes ◽  
Ostertagia Ostertagi ◽  
Protein Substrates ◽  
Stage Specificity ◽  
Specific Manner ◽  
Secretory Products

AbstractProteolytic enzymes present in extracts of third (L3) and fourth (L4) stage larvae and adults of the cattle nematode Ostertagia ostertagi were defined on the basis of pH optima and proteinase inhibitor sensitivity in spectrophotometric assays using azocasein and elastin-orcein as protein substrates. Evidence that different classes of proteinases are expressed in a stage specific manner was provided by the contrasting pH optima and inhibitor sensitivities shown by the enzymes in the different parasite stages. Stage specificity was confirmed by gelatin-substrate analysis. In addition, proteolytic activity was sought in the excretory/secretory products (ES) of the L4 following simple in vitro culture. Contrasting pH and inhibitor sensitivities as well as gelatin-substrate analysis showed that different proteinases were present in somatic L4 extracts and L4 ES products. The secreted proteinases may be useful targets for serodiagnosis or vaccination.

Bioactive peptide derived from in vitro proteolysis of bovine β-lactoglobulin and its effect on smooth muscle

1997 ◽  
Vol 64 (1) ◽  
pp. 149-155 ◽  
Author(s):  
ANNE PIHLANTO-LEPPÄLÄ ◽  
ILARI PAAKKARI ◽  
MERJA RINTA-KOSKI ◽  
PIRKKO ANTILA
Keyword(s):  
Guinea Pig ◽  
Proteolytic Enzymes ◽  
Whey Proteins ◽  
Casein Hydrolysate ◽  
Milk Proteins ◽  
Biologically Active ◽  
Guinea Pig Ileum ◽  
Β Lactoglobulin

Milk proteins have largely been considered as providing essential amino acids, but oligopeptides derived from milk proteins have been shown to possess biological functions. In vitro, opioid activity was first reported in bovine β-casein hydrolysate by Brantl et al. (1979). Precursors of biologically active peptides have been demonstrated in vivo after digestion of milk (Scanff et al. 1992). Peptides that inhibit platelet aggregation (Fiat et al. 1989), stimulate the immune system (Migliore-Samour et al. 1989), inhibit angiotensin I converting enzyme (Maruyama & Suzuki, 1982) and are involved in intestinal Ca solubilization and absorption (Sato et al. 1986) have also been isolated from bovine casein hydrolysates.Bioactive peptides from whey proteins and their physiological effects have received less attention than those from casein. Peptides with opiate-like activity include the lactorphins, residues 50–53 in bovine and human α-lactalbumin and 102–105 in bovine β-lactoglobulin (β-lg) (Chiba & Yoshikawa, 1986; Yoshikawa et al. 1986; Antila et al. 1991). Yamauchi (1992) has reported that a peptide derived from β-lg induced contraction of guinea pig ileum longitudinal muscle in the absence of electric stimulation and agonist. The fragment, containing residues 146–149 of β-lg (His–Ile–Arg–Leu), was called β-lactotensin.The purpose of this study was to determine whether β-lactotensin was released from bovine β-lg by in vitro proteolysis using different proteolytic enzymes. The pharmacological activity of this tetrapeptide was characterized in guinea pig ileum in vitro using a synthetic fragment.

Formation and Structure of Casein Micelles in Lactating Mammary Tissue

1970 ◽  
Vol 28 ◽  
pp. 150-151
Author(s):  
Robert J. Carroll ◽  
Marvin P. Thompson ◽  
Harold M. Farrell
Keyword(s):  
Size Distribution ◽  
G Protein ◽  
Milk Proteins ◽  
Mammary Tissue ◽  
Colloidal System ◽  
Casein Micelles ◽  
The Stability

Milk is an unusually stable colloidal system; the stability of this system is due primarily to the formation of micelles by the major milk proteins, the caseins. Numerous models for the structure of casein micelles have been proposed; these models have been formulated on the basis of in vitro studies. Synthetic casein micelles (i.e., those formed by mixing the purified αsl- and k-caseins with Ca2+ in appropriate ratios) are dissimilar to those from freshly-drawn milks in (i) size distribution, (ii) ratio of Ca/P, and (iii) solvation (g. water/g. protein). Evidently, in vivo organization of the caseins into the micellar form occurs in-a manner which is not identical to the in vitro mode of formation.

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