• Korean journal of food and cookery science
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• v.13 no.2
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• pp.168-172
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• 1997

Yolk immunoglobulins (yIgG) from hen's egg were purified. To investigate the stability of yIgG to digestive enzymes, the changes of antigen binding activities (ABC) after in vitro proteolysis were examined by competitive ELISA. After 30 min exposure to pepsin, the ABC of yIgG was lost. However, comparing with native yIgG, the ABC of pepsin digested yIgG was decreased, but considerable amount of ABC was remained after 30 min exposure to pepsin in 50% saccharose solution. Therefore, the stability of yIgG to pepsin digestion was improved by the addition of saccharose to yIgG solution. The ABC of yIgG was considerably remained after exposure to trypsin and chymotrypsin for 8 hr. YIgG showed especially good stability to chymotrypsin proteolysis.

• KSBB Journal
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• v.9 no.2
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• pp.165-173
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• 1994

In this paper we have described the structural characterization of recombinant bovine somatotropin produced in Escherichia coli. Recombinant bovine somatotropin consists of 191 amino acid residues with a calculated molecular weight of 21,802 Da. For fragmentation of recombinant bovine somatotropin, we have used trypsin, Staphylococcus aureus V8 pretease, CNBr, and mild acid hydrolysis method. Digestion and cleavage with these proteases and chemicals yielded peptides of various size for amino acid sequence determination. The N-terminal sequence analysis was carried out up to thirty residues. Because the design of the recombinant bovine somatotropin gene for expression was such that the coding sequence begins with an initiation codon, AUG, before Ala, the first amino acid of bovine somatotropin, we could expect the initial amino acid as N-formyl Met. But the first amino acid of this protein, expressed in E. coli cells as inclusion bodies, was Ala. And the amino acid composition of RP-HPLC purified recombinant bovine somatotropin was determined and no essencial difference was observed. The amino acid sequence of the recombinant bovine somatotropin was identical to that predicted from its recombinant gene. There was no processing or replacement of amino acid residues in recombinant bovine somatotropin expressed in E. coli. The hydropathy plot of recombinant bovine somatotropin revealed a hydrophobic region at the NH2-terminus and hydrophilic region at the COOH-terminus. The E. coli expression system is thought to be valuable for the expression of recombinant bovine somatotropin because protein was processed to remove the N-terminal Met residue by methionyl-aminopeptidase autonomously.

• Animal Bioscience
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• v.34 no.12
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• pp.1981-1986
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• 2021

Objective: This study aimed to investigate the effect of Salvia miltiorrhiza (S.m.) aerial parts as an alternative ingredient on growth performance, nutrient digestibility, and digestive enzymes in growing rabbits. Methods: Treatments included five tested diets: a control (basal diet), antibiotic (basal diet+enramycin at 5 mg/kg), and S.m. aerial parts powder added at 3.0%, 6.0%, and 9.0% of feed using 300 growing rabbits. Results: The diets with S.m. aerial parts addition at 9.0% decreased (p<0.05) feed/gain compared to the control, but there were no differences in feed intake and body weight gain. In contrast with the control, the addition of antibiotic increased (p<0.05) digestibility of dry matter, crude protein, energy, fiber, and ash. The herb addition did not cause differences in the digestibility of most nutrients compared to the antibiotic, but fiber digestibility of the herb at 6.0% and 9.0% was lower (p<0.05) than that of the antibiotic. Moreover, the antibiotic and the herb also similarly increased (p<0.05) the activities of duodenal α-amylase, maltase, lipase, and trypsin, compared to the control, and the herb at 6.0% and 9.0% showed a greater (p<0.05) activity of elastase than the dose 3.0%. Conclusion: The obtained data indicate that S.m. aerial parts can be a potential forage in rabbit's diet at 9.0% with a beneficial regulation on nutrition and digestion.

• Food Science of Animal Resources
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• v.44 no.3
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• pp.533-550
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• 2024

Peptides with bioactive effects are being researched for various purposes. However, there is a lack of overall research on pork-derived peptides. In this study, we reviewed the process of obtaining bioactive peptides, available analytical methods, and the study of bioactive peptides derived from pork. Pepsin and trypsin, two representative protein digestive enzymes in the body, are hydrolyzed by other cofactors to produce peptides. Bicinchoninic acid assay, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, chromatography, and in vitro digestion simulation systems are utilized to analyze bioactive peptides for protein digestibility and molecular weight distribution. Pork-derived peptides mainly exhibit antioxidant and antihypertensive activities. The antioxidant activity of bioactive peptides increases the accessibility of amino acid residues by disrupting the three-dimensional structure of proteins, affecting free radical scavenging, reactive oxygen species inactivation, and metal ion chelating. In addition, the antihypertensive activity decreases angiotensin II production by inhibiting angiotensin converting enzyme and suppresses blood pressure by blocking the AT1 receptor. Pork-derived bioactive peptides, primarily obtained using papain and pepsin, exhibit significant antioxidant and antihypertensive activities, with most having low molecular weights below 1 kDa. This study may aid in the future development of bioactive peptides and serve as a valuable reference for pork-derived peptides.

• Clinical and Experimental Reproductive Medicine
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• v.33 no.3
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• pp.189-198
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• 2006

Objective: We previously described that Diva is highly expressed in matured metaphase II (MII) oocytes compared to immature germinal vesicle (GV) oocytes in mouse. We report here that the expression of Diva transcript as well as protein is oocyte-specific. To elucidate its physiological role in oocyte, the binding partner(s) of Diva has been identified by using immunoprecipitation (IP) followed by Mass Spectrometry. Methods: NIH/3T3 cells were transiently transfected for 24 h with either empty vector for control or FLAG-tagged mouse Diva construct, and IP was performed with anti-FLAG antibody. The immuno-isolated complexes were resolved by SDS-PAGE on a 12% gel followed by Coomassie Blue staining. For in-gel digestion, 15 bands of interest were excised manually and digested with trypsin. All mass spectra were acquired at a positive reflector mode by a 4700 Proteomics Analyzer (Applied Biosystems, Framingham, MA). Proteins were identified by searching the NCBI nonredundant database using MASCOT Peptide Mass Fingerprint software (Matrixscience, London). Results: Diva-associated complexes were formed in FLAG-tagged mouse Diva-overexpressed NIH/3T3 cells via IP using anti-FLAG-conjugated beads. Among the excised 15 bands, actin and actin-binding proteins such as tropomyosin, tropomodulin 3, and ${\alpha}$-actinin were identified. Binding between Diva and actin or tropomyosin was confirmed by IP followed by Western blot analysis. Both bindings were also detected endogenously in mouse ovaries, indicating that Diva works with actin and tropomyosin. Conclusions: This is the first report that immuno-isolated Diva-associated complexes are related to actin filament of the cytoskeletal system. When we consider the association of Diva with actin and tropomyosin, oocyte-specific Diva may play a role in modulating the cytoskeletal system during oocyte maturation.

• Food Science of Animal Resources
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• v.38 no.4
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• pp.780-793
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• 2018

This study was conducted to compare the anti-allergic effects of a whey protein concentrate (WPC) and WPC hydrolysate. WPC hydrolysate was prepared using enzymatic digestion for 8 h with trypsin and ${\alpha}$-chymotrypsin, after which it was freeze-dried. The allergic parameters assessed in rat basophilic leukemia (RBL)-2H3 cells were degranulation and release of ${\beta}$-hexosaminidase, release of tumor necrosis factor $(TNF)-{\alpha}$, and changes in the expression of $IL-1{\beta}$, IL-4, and IL-10 by real time polymerase chain reaction (PCR). During preparation of the WPC hydrolysate, hydrolysis increased rapidly from 0 to 10 min and then gradually increased slowly from 1 h onwards, achieving a final degree of hydrolysis of 78.50%. The SDS-PAGE analysis revealed a reduction in the intensity of several protein bands in the WPC hydrolysate compared to the WPC. IgE-induced ${\beta}$-hexosaminidase release from RBL-2H3 cells was decreased to a higher degree following treatment with the hydrolysate compared to WPC treatment. W500 ($500{\mu}g/mL$ WPC) showed the least inhibition of ${\beta}$-hexosaminidase release, but there was no significant difference between W500 and W1000 ($1,000{\mu}g/mL$) (p<0.05). H1000 ($1,000{\mu}g/mL$ WPC hydrolysate) inhibited ${\beta}$-hexosaminidase release by 39%. Compared to the control, treatment with H1000 decreased $TNF-{\alpha}$ secretion to 11.87 pg/mL. The gene expression levels of IL-1${\beta}$, IL-4, and IL-13 were all significantly decreased in hydrolysate (p<0.05). In the case of $IL-1{\beta}$ and IL-4, the expression levels in W1000 treated cells were decreased by 73.67% and 65%, respectively, and that of IL-13 was decreased by 66.43% compared to the control.

• Journal of Animal Science and Technology
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• v.44 no.4
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• pp.483-490
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• 2002

The aim of this study was to determine if a low-molecular weight casein hydrolysate has an anti- hypertensive effect in spontaneously hypertensive rats (SHR). Prior to the in vivo experiment, the casein hydrolysate was confirmed to be resistant to gastrointestinal digestion by confirming the retention of its potency as an inhibitor of angiotensin I-concerting enzyme after incubation with pepsin, trypsin, or chymotrypsin. The in vivo anti-hypertensive effect of the hydrolysate was determined by the tail cuff method. Following an oral administration of the hydrolysate solution, the systolic blood pressure (SBP) decreased by 12.9% (－28.9mmHg; P<0.05) at 3 h after the administration at a dose of 500mg/kg body weight. When the hydrolysate was administered as an emulsion with 30% egg yolk, its anti-hypertensive effect was even more greater at the same dose(－30.8mmHg or －15.9%; P<0.01). In a 50-day long-term trial where the casein hydrolysate was administered once a day, the SBP-lowering effect of the hydrolysate was apparent (P<0.05) from day 35 through the end. Moreover, organ weights and plasma glutamate oxaloacetate transaminase and glutamate pyruvate transaminase activities of the administered SHR were not significantly different from those of controls at the end of the long-term trial.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.4
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• pp.207-211
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• 2004

The purpose of the present study was to evaluate the expression of cardiac marker protein in rabbit cardiac tissue that was exposed to ischemic preconditioning (IPC), or ischemiareperfusion injury (IR) using two-dimensional gel electrophoresis (2DE) and matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS). We compared 2DE gels of control (uninjured) cardiac tissue with those of IPC and IR cardiac tissue. Expression of one protein was detected in IR heart tissue, however the protein was not detected in the samples of control and IPC tissue. To further characterize the detected protein molecule, the protein in the 2D gel was isolated and subjected to trypsin digestion, followed by MALDI-MS. The protein was identified as myoglobin, which was confirmed also by Western blot analysis. These results are consistent with previous studies of cardiac markers in ischemic hearts, indicating myoglobin as a suitable marker of myocardial injury. In addition, the present use of multiple techniques indicates that proteomic analysis is an appropriate means to identify cardiac markers in studies of IPC and IR.

• Journal of Microbiology and Biotechnology
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• v.22 no.11
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• pp.1532-1539
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• 2012

The ${\alpha}$-galactosidase-coding gene agaAJB13 was cloned from Sphingomonas sp. JB13 showing 16S rDNA (1,343 bp) identities of ${\leq}97.2%$ with other identified Sphingomonas strains. agaAJB13 (2,217 bp; 64.9% GC content) encodes a 738-residue polypeptide (AgaAJB13) with a calculated mass of 82.3 kDa. AgaAJB13 showed the highest identity of 61.4% with the putative glycosyl hydrolase family 36 ${\alpha}$-galactosidase from Granulicella mallensis MP5ACTX8 (EFI56085). AgaAJB13 also showed <37% identities with reported protease-resistant or Sphingomonas ${\alpha}$-galactosidases. A sequence analysis revealed different catalytic motifs between reported Sphingomonas ${\alpha}$-galactosidases (KXD and RXXXD) and AgaAJB13 (KWD and SDXXDXXXR). Recombinant AgaAJB13 (rAgaAJB13) was expressed in Escherichia coli BL21 (DE3). The purified rAgaAJB13 was characterized using p-nitrophenyl-${\alpha}$-D-galactopyranoside as the substrate and showed an apparent optimum at pH 5.0 and $60^{\circ}C$ and strong resistance to trypsin and proteinase K digestion. Compared with reported proteaseresistant ${\alpha}$-galactosidases showing thermolability at $50^{\circ}C$ or $60^{\circ}C$ and specific activities of <71 U/mg with or without protease treatments, rAgaAJB13 exhibited a better thermal stability (half-life of >60 min at $60^{\circ}C$) and higher specific activities (225.0-256.5 U/mg). These sequence and enzymatic properties suggest AgaAJB13 is the first identified and characterized Sphingomonas ${\alpha}$-galactosidase, and shows novel protease resistance with a potential value for basic research and industrial applications.

• Clinical and Experimental Reproductive Medicine
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• v.27 no.1
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• pp.23-29
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• 2000

Objective: Zona pellucida (ZP) has been thought to be the barrier of egg to sperm penetration before and after fertilization. The phenomenon of ZP hardening has been considered as a post-fertilization event until now, and it is generally accepted that it is caused by the secretory products of cortical granules released during the cortical reaction. Hardening of ZP could occur "spontaneously" in mammalian oocytes in standard culture conditions, and that it is probably not a consequence of cortical reaction. The purpose of our study was to investigate the effect of human amniotic fluid (HAF) on nuclear maturation (NM) and fertilization ability of mouse immature oocytes. Methods: HAF was obtained from patients undergoing amniocentesis at $16{\sim}20$ weeks of gestation. HAF from five to ten patients was centrifuged and the supernatants was pooled. Cumulusenclosed mouse immature oocytes were incubated in the medium containing HAF, and examined to confirm NM and fertilization. Female ICR mice (about 3 weeks old) were stimulated with 7.5 IU PMSG. Immature oocytes were isolated at $48{\sim}52$ hrs post PMSG injection and cultured in TCM-199 supplemented with 20% HAF for 18 hrs. FBS was used as a control for the examination. Matured oocytes (MII) were fertilized with sperms collected from the epididymis of male mice (over 10 weeks old). Fertilization was in conducted T6 medium containing 15 mg/ml BSA, and confirmed at 6 hrs post-insemination. Fertilization rate was assessed in zona-intact or zona-free oocytes (denuded by trypsin). Evaluation of NM and fertilization was carried out by rapid staining method. ZP hardening was evaluated by incubating cumulus cell-free mature oocytes in 0.001% chymotrypsin at $37^{\circ}C$ for 10 min. Results: There was no significant difference between the effects of HAF (86.6%) and FBS (87.7%) supplements on NM of immature oocytes. When maturation medium was supplemented with HAF, total fertilization rates (7%) were significantly lower (p<0.01) than that of FBS (85.1%). In HAF group, fertilization rate was increased (p<0.01) in zona-free oocytes (7% versus 100%). The resistance of mouse oocyte ZP to digestion by chymotrypsin after maturation in vitro was significantly higher (p<0.01) in HAF group (86.7%) than in FBS (6.7%). To culture oocytes in FBS were very effective in preventing ZP hardening. However cultured oocytes in HAF showed high rate of ZP hardening (p<0.01). Conclusions: These results suggest that HAF can be used as a supplement for the NM of mouse immature oocytes in vitro. However, HAF induces spontaneous hardening of ZP of mouse immaure oocytes during maturation in vitro.