• Journal of Animal Science and Technology
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• 제65권1호
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• pp.32-56
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• 2023

This review explores the factors that improve meat protein digestibility and applies the findings to the development of home meal replacements with improved protein digestion rates in older adults. Various methods improve the digestion rate of proteins, such as heat, ultrasound, high pressure, or pulse electric field. In addition, probiotics aid in protein digestion by improving the function of digestive organs and secreting enzymes. Plant-derived proteases, such as papain, bromelain, ficin, actinidin, or zingibain, can also improve the protein digestion rate; however, the digestion rate is dependent on the plant enzyme used and protein characteristics. Sous vide processing improves the rate and extent of protein digestibility, but the protein digestion rate decreases with increasing temperature and heating time. Ultrasound, high pressure, or pulsed electric field treatments degrade the protein structure and increase the proteolytic enzyme contact area to improve the protein digestion rate.

• 한국축산식품학회지
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• 제44권4호
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• pp.885-898
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• 2024

Ovomucin (OM), which has insoluble fractions is a viscous glycoprotein, found in egg albumin. Enzymatic hydrolysates of OM have water solubility and bioactive properties. This study investigated that the immunostimulatory effects of OM hydrolysates (OMHs) obtained by using various proteolytic enzymes (Alcalase^®, bromelain, α-chymotrypsin, Neutrase^®, pancreatin, papain, Protamax^®, and trypsin) in RAW 264.7 cells. The results showed that OMH prepared with pancreatin (OMPA) produced the highest levels of nitrite oxide in RAW 264.7 cells, through upregulation of inducible nitric oxide synthase mRNA expression. The production of pro-inflammatory cytokines such as tumor necrosis factor-α and interleukin-6 were increased with the cytokines mRNA expression. The effect of OMPA on mitogen-activated protein kinase signaling pathway was increased the phosphorylation of p38, c-Jun NH2-terminal kinase, and extracellular signal-regulated kinase in a concentration-dependent manner. Therefore, OMPA could be used as a potential immune-stimulating agent in the functional food industry.

• Food Science and Biotechnology
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• 제17권2호
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• pp.279-286
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• 2008

The antioxidative activity of various enzymatic extracts from leaves of Perilla frutescens var. japonica was evaluated by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, and alkyl radical scavenging activity using an electron spin resonance (ESR) spectrometer. For this study, the leaves were enzymatically hydrolyzed by 8 carbohydrases (Dextrozyme, AMG, Promozyme, Maltogenase, Termamyl, Viscozyme, Celluclast, and BAN) and 9 proteases [Flavourzyme, Neutrase, Protamex, Alcalase, PP-trypsin (trypsin from porcine pancreas), papain, pepsin, $\alpha$-chymotrypsin, and BP-trypsin (trypsin from bovine pancreas)]. The DPPH radical scavenging activities of Promozyme and Alcalase extracts were the highest, and the $IC_{50}$ values were 77.25 and $109.66\;{\mu}g/mL$, respectively. All enzymatic extracts of the leaves scavenged hydroxyl radical, and the $IC_{50}$ values of Celluclast and pepsin extracts which were the highest activity were 243.34 and $241.86\;{\mu}g/mL$, respectively. The BAN and $\alpha$-chymotrypsin extracts showed the highest scavenging activities, and the $IC_{50}$ values were 21.13 and $33.23\;{\mu}g/mL$, respectively. The pepsin extracts from the leaves showed protective effect on $H_2O_2$-induced DNA damage. In addition, the pepsin extracts decreased cell death in PC-12 cells against $H_2O_2$-induced oxidative damage. The findings of the present study suggest that enzymatic extracts of the leaves possess antioxidative activity.

• 한국축산식품학회지
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• 제35권4호
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• pp.486-493
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• 2015

This research focuses on a new softening technology for use with chicken breast and eye of round beef in order to assist elderly individuals who have difficulty with eating due to changes in their ability to chew (masticatory function) or swallow. We investigated the hardness of chicken breast and eye of round beef through use of a texture analyzer after injection of a commercial enzyme. Among 7 commercial enzymes, bromelain and collupulin exhibited a marked softening effect on the tested chicken breast and eye of round beef given a 1.00% enzyme concentration. The hardness of bromelain-treated chicken breast reached 1.4×10⁴ N/m², of collupulin-treated chicken breast reached 3.0×10⁴ N/m², and of bromelain-treated eye of round beef reached 3.2×10⁴ N/m², respectively, while their original shapes did not change. To find the level of tissue degradation with specific enzyme concentrations, enzyme injections at 0.1%, 0.25%, 0.50%, and 1.00% concentration of bromelain and papain were also evaluated. The results of this research could be useful for softening chicken breast and eye of round beef and will contribute to the development of foods that can be more easily eaten as part of a balanced diet for elderly adults.

• 생명과학회지
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• 제28권6호
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• pp.753-763
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• 2018

Cathepsin은 리소좀에 존재하는 효소로, 엔도좀-리소좀 경로를 통하여 손상된 단백질의 분해를 유도한다. 이러한 cathepsin은 활성화되는 촉매 잔기 위치(catalytic residue site)에 따라 cysteine, aspartate, serine cathepsin으로 나뉜다. 다양한 암세포에서 cysteine cathepsin은 유전자 증폭이나 전사, 번역, 전사 후 단계를 통해 높은 발현을 유지한다. 특히 cathepsin S의 경우, 다른 cysteine cathepsin과 달리 중성 pH 환경에서도 안정적으로 활성도를 유지하며 특정 조직에서 발현이 제한적이라는 특징을 가지고 있기 때문에 질병의 미세환경에서 중요한 역할을 한다. 면역세포에서의 cathepsin S는 불변 사슬(invariant chain)을 분해하여 항원 제시에 중요한 MHC class II의 활성화를 통해 면역 반응을 조절하며, 암세포에서의 cathepsin S는 전이와 혈관신생을 조절함으로써 암세포의 성장을 증가시키는 역할을 한다. Cathepsin S의 발현 조절에 문제가 생기면 암, 관절염, 심혈관 질환을 포함한 많은 병리학적 현상에 영향을 미친다. 특히 암세포에서 cathepsin S의 발현 억제와 결함은 혈관신생을 억제시킬 뿐만아니라, 암세포의 성장과 전이를 감소시키고 세포사멸을 유도한다. 따라서, cathepsin S는 암 치료에 있어 좋은 표적이 될 수 있다.

• 한국약용작물학회지
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• 제19권2호
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• pp.77-82
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• 2011

The antioxidative activity of various enzymatic extracts from Sarcodon aspratus (S. aspratus) was evaluated by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH), and alkyl radical scavenging activity using an electron spin resonance (ESR) spectrometer. For this study, the S. aspratus were enzymatically hydrolyzed by seven carbohydrases (Viscozyme, Celluclast, Dextrozyme, AMG, Promozyme, Maltogenase, and Termamyl) and eight proteases (${\alpha}$-chymotrypsin, Alcalase, Flavourzyme, Neutrase, papain, pepsin, Protamax, and trypsin). The DPPH radical scavenging activities of Viscozyme and pepsin extracts were the highest, and the half maximal inhibitory concentration ($IC_{50}$) values were 0.896 and 0.734mg/mL, respectively. The Celluclast and trypsin extracts showed the highest scavenging activities on alkyl radical, and their $IC_{50}$ values were 0.278 and 0.575mg/mL, respectively. The Celluclast extracts was decreased cell apoptosis in PC-12 cells against $H_2O_2$-induced oxidative damage. The findings of the present study suggest that enzymatic extracts of S. aspratus exhibit antioxidative activity against oxidative stress on PC-12 cells.

• BMB Reports
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• 제31권4호
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• pp.364-369
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• 1998

Insect plasma protein is abundant in the hemolymph of holometabolous insect larvae and is used as a source of amino acids and energy for construction of adult structures during metamorphosis. In order to understand the mechanism of decomposition of larval plasma proteins by hemocyte protease, we tried to purify a cysteine protease from the hemocyte lysate by using Carbobenzoxy-L-Phenylalanyl-L-Arginine-4-Methyl-Coumaryl-7-Amide (Z-Phe-Arg-MCA) as substrate and to identify plasma proteins that are selectively susceptible to the purified protease. Here, we describe the purification and characterization of a cysteine protease that specifically hydrolyzes the plasma protein of the coleopteran insect, Tenebrio molitor, larvae. The molecular mass of this enzyme was 25 kDa, as determined by SDS-PAGE under reducing conditions. The amino acids sequence of its $NH_{2}-terminus$ was determined to be Leu-Pro-Gly-Gln-Ile-Asp-Trp-Arg-Asp-Lys-Gly. This sequence contained Pro, Asp, and Arg residues, conserved in many papain superfamily enzymes. The specific cysteine protease inhibitors, such as E-64 and leupetin, inhibited its hydrolytic activity. One plasma protein with a molecular mass of 48 kDa was selectively hydrolyzed within 3 h when the purified enzyme and plasma proteins were incubated in vitro. However, the 48 kDa protein was not hydrolyzed by the purified 25 kDa protease in the presence of E-64. Western blotting analysis at various developmental stages showed that the purified enzyme was detected at larvae, pupae, and adult stages, but not the embryo stage.

• Journal of Microbiology and Biotechnology
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• 제20권8호
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• pp.1243-1250
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• 2010

A cDNA encoding a cysteine protease inhibitor (CPI) was isolated from the cDNA library of clamworm Perinereis aibuhitensis Grube. The deduced amino acid sequence analysis showed that the protein had 51%, 48%, and 48% identity with Zgc:153129 from Danio rerio, cystatin B from Theromyzon tessulatum, and the ChainA, stefin B tetramer from Homo sapiens, respectively. The gene was cloned into the intracellular expression vector pET-15b and expressed in Escherichia coli. The recombinant CPI (PA-CPI) was purified by affinity chromatography on Ni-charged resin and ion-exchange chromatography on DEAE-Sepharose FF. The relative molecular mass of PA-CPI was 16 kDa as deduced by SDS-PAGE. Activity analysis showed that the recombinant protein could inhibit the proteolytic activity of papain. A constitutive and secretive expression vector was also constructed, and the cDNA encoding CPI was subcloned into the vector for extracellular expression. Western blotting analysis results showed that the PA-CPI was secreted into the medium. Bioassay demonstrated that E. coli DH5${\alpha}$ harboring pUC18ompAcat-CPI showed a significant difference in mortality to the Asian longhorned beetle Anoplophora glabripennis compared with untransformed E. coli DH5${\alpha}$ and control.

• Journal of Microbiology and Biotechnology
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• 제28권9호
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• pp.1554-1562
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• 2018

The type I interferons (IFNs) play a vital role in activation of innate immunity in response to viral infection. Accordingly, viruses have evolved to employ various survival strategies to evade innate immune responses induced by type I IFNs. For example, hepatitis E virus (HEV) encoded papain-like cysteine protease (PCP) has been shown to inhibit IFN activation signaling by suppressing K63-linked de-ubiquitination of retinoic acid-inducible gene I (RIG-I) and TANK-binding kinase 1 (TBK1), thus effectively inhibiting down-stream activation of IFN signaling. In the present study, we demonstrated that HEV inhibits polyinosinic-polycytidylic acid (poly(I:C))-induced $IFN-{\beta}$ transcriptional induction. Moreover, by using reporter assay with individual HEV-encoded gene, we showed that HEV methyltransferase (MeT), a non-structural protein, significantly decreases RIG-I-induced $IFN-{\beta}$ induction and $NF-{\kappa}B$ signaling activities in a dose-dependent manner. Taken together, we report here that MeT, along with PCP, is responsible for the inhibition of RIG-I-induced activation of type I IFNs, expanding the list of HEV-encoded antagonists of the host innate immunity.

• The Korean Journal of Physiology and Pharmacology
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• 제12권2호
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• pp.73-77
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• 2008

Recent studies have documented that testosterone relaxes several smooth muscles by modulating $K^+$ channel activities. Smooth muscles of seminal vesicles playa fundamental role in ejaculation, which might involve testosterone. This study was aimed to assess the role of testosterone in seminal vesicular motility by studying its effects on contractile agents and on the ion channels of single vesicular myocytes in a rabbit model. The contractile responses of circular smooth muscle strips of rabbit seminal vesicles to norepinephrine ($10{\mu}M$), a high concentration of KCI (70 mM), and testosterone ($10{\mu}M$) were observed. Single vesicular myocytes of rabbit were isolated using proteolytic enzymes including collagenase and papain. Inside-out, attached, and whole-cell configurations were examined using the patch clamp technique. The applications of $10{\mu}M$ norepinephrine or 70 mM KCl induced tonic contractions, and $10{\mu}M$ testosterone (pharmacological concentration) evoked dose-dependent relaxations of these precontracted strips. Various $K^+$ channel blockers, such as tetraethylammonium (TEA; $10{\mu}M$), iberiotoxin ($0.1{\mu}M$), 4-aminopyridine (4-AP, $10{\mu}M$), or glibenclamide ($10{\mu}M$) rarely affected these relaxations. Single channel data (of inside-out and attached configurations) of BK channel activity were also hardly affected by testosterone ($10{\mu}M$). On the other hand, however, testosterone reduced L-type $Ca^{2+}$ currents significantly, and found to induce acute relaxation of seminal vesicular smooth muscle and this was mediated, at least in part, by $Ca^{2+}$ current inhibition in rabbit.