• Food Science of Animal Resources
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• v.40 no.4
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• pp.613-627
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• 2020

Paprika is known to contain polyphenolic compounds that have good antioxidant properties. This study was conducted to investigate the benefits of adding paprika juice of different colors to yogurt and to determine how paprika affects the quality characteristics of yogurt. Stirred yogurt samples supplemented with different levels of red, orange, or yellow paprika juice were inoculated with mixes of Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus. Paprika addition decreased the pH but increased titratable acidity, lactic acid bacteria (LAB) counts, total polyphenol content (TPC), levels of vitamin A and C, and antioxidant activity. Proteolysis and viscosity of paprika-containing yogurts were significantly higher than those of the control yogurt without paprika juice (p<0.05). In particular, the viscosity of red paprika yogurt was significantly higher than that of yogurts containing 5% orange and yellow paprika juices (each p<0.05). The antioxidant activity of the methanol extract of the yogurt containing 2.5% orange paprika juice was the highest. Storage at 4℃ for 15 days only slightly altered LAB counts, antioxidant activity, and TPC of paprika yogurt. These results indicate that paprika could be used as a natural food additive for the development of functional yogurts.

• Korean Journal of Food Science and Technology
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• v.8 no.1
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• pp.6-11
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• 1976

1. Three hundred and thirty three strains of thermoduric bacteria from raw milk, H.T.S.T. sterilized milk and U.H.T. sterilized milk in the market were isolated after heat treatment at $65^{\circ}C$ for 30 minutes. 2. By microscopical and physiological examination, including the tests for proteolysis and lipolysis, the isolates were identified as 125 strains of Bacillus stearothermophilus, 69 strains as Bacillus coagulans, 57 strains as Bacillus subtilis, 76 strains as Bacillus cereus and 3 strains as Lactobacillus thermophilus. 3. The susceptibility of the selected thermoduric strains to heat, the vegetative cells of some strains in skim milk survived the heat treatment at $65^{\circ}C$ for 30 minutes or $85^{\circ}C$ for 20 minutes but not survived at $100^{\circ}C$ for 10 minutes.

• BMB Reports
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• v.36 no.1
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• pp.128-137
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• 2003

Matrix metalloproteinases (MMPs), zinc dependent proteolytic enzymes, cleave extracellular matrix (ECM: collagen, laminin, firbronectin, etc) as well as non-matrix substrates (growth factors, cell surface receptors, etc). The deregulation of MMPs is involved in many diseases, such as tumor metastasis, rheumatoid arthritis, and periodontal disease. Metastasis is the major cause of death among cancer patients. In this review, we will focus on the roles of MMPs in tumor metastasis. The process of metastasis involves a cascade of linked, sequential steps that involve multiple host-tumor interactions. Specifically, MMPs are involved in many steps of tumor metastasis. These include tumor invasion, migration, host immune escape, extravasation, angiogenesis, and tumor growth. Therefore, without MMPs, the tumor cell cannot perform successful metastasis. The activities of MMPs are tightly regulated at the gene transcription levels, zymogen activation by proteolysis, and inhibition of active forms by endogenous inhibitors, tissue inhibitor of metalloproteinase (TIMP), and RECK. The detailed regulations of MMPs are described in this review.

• Korean Journal of Veterinary Research
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• v.55 no.3
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• pp.175-179
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• 2015

Proteases play important roles in parasite development and host parasite interactions. The protease of Kudoa spp. has been recognized as a key factor of severe proteolysis of fish muscle post-mortem; however, there is little information available regarding the protease of Kudoa (K.) septempunctata, which was recently identified as a cause of food poisoning in humans. The present study was conducted to isolate and characterize proteases to elucidate the type of protease contained in the parasite and determine the optimal pH for protease activity. We confirmed the cysteine protease and metalloprotease produced by K. septempunctata. While the cysteine protease showed optimal activity at pH 5 that decreased rapidly with increasing pH, the optimal activity of metalloprotease was pH 7, and it remained stable from pH 6 to pH 8. These results indicate that the pH of cysteine protease is not proper for fish muscle postmortem, and that metalloprotease can act in human intestines. Overall, the present study provides important information that improves our understanding of the role of protease physiology and the subsequent food poisoning caused by K. septempunctata.

• BMB Reports
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• v.30 no.2
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• pp.125-131
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• 1997

This work reports studies of the catalytic and structural properties of pyridoxal kinase (ATP: pyridoxal 5' -phosphotransferase, EC. 2.7.1.35), Pyridoxal kinase catalyzes the phosphorylation of vitamin $B_6$ (pyridoxal, pyridoxamine, pyridoxine) using ATP-Zn as a phosphoryl donor. The enzyme purified from brain tissues is made up of two identical subunits of 40 kDa each. Native enzyme was inhibited by a substrate analogue, pyridoxal-oxime. Limited chymotrypsin digestion of pyridoxal kinase yields two fragments of 24 and 16 kDa with concomitant loss of catalytic activity. These fragments were isolated by DEAE ion exchange chromatography and used for binding studies with fluorescent ATP and pyridoxal analogues. The spectroscopic properties of both fluorescent pyridoxal analogue and Anthraniloyl ATP (Ant-ATP) bound to the 24 kDa fragment are indistinguishable from those of both pyridoxal analogue and Ant-ATP bound to the native pyridoxal kinase, respectively. The small 16 kDa fragment, generated by proteolytic cleavage of the kinase, does not bind any of the substrate analogues. Binding characteristics of Ant-ATP were extensively studied by measuring the changes in fluorescence spectra at various conditions. From the results presented herein, it is postulated that the structural domain associated with catalytic activity comprises approximately one-half of the molecular mass of pyridoxal kinase (24 kDa). whereas the remaining portion (16 kDa) of the enzyme contains a regulatory binding domain.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2006.11a
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• pp.60-61
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• 2006

Effect of dietary salmonella lysate in broiler chicks inoculated with Salmonella typhimurium on the antioxidant system(freshness) of broiler meats during 4$^{\circ}$C refrigeration was investigated. In Pectoral and leg muscle, regardless experimental diets, as the refrigeration day passed, CuZnSOD activity decreased gradually, while at 7d MnSOD activity and peroxide level raised and then lowered at 14d. MnSOD and peroxidase activity, however, had differed according to experimental diets. The results indicated that antioxidant system of broiler meats will be changed according to experimental diets(nutrients). As the CuZnSOD, MnSOD and peroxidase activity are responsible for proteolysis of muscle protein, it was concluded that change of antioxidant system during 4$^{\circ}$C storage explain the biological activity(freshness) of broiler meats.

• Journal of Pharmaceutical Investigation
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• v.27 no.1
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• pp.15-22
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• 1997

The mucosal route of administration(nasal, buccal, conjunctival and vaginal) has recently been considered as an alternative to parenteral delivery for many peptide drugs because enzymatic degradation of these agents may be partly avoided. The objective of these study was to establish the optimal mucosal administration dosage form of $LHRH/[D-Ala^6]LHRH$, based on presystemic metabolism. We reported previously the peptidase inhibition effect of medium chain fatty acid salts(sodium caprylate, soadium caprate and sodium laurate), EDTA and STDHF on the proteolysis of $LHRH/[D-Ala^6]LHRH$ in rabbit mucosal homgenates. We also reported that EDTA, STDHF and sodium laurate markedly increased the potency of $LHRH/[D-Ala^6]LHRH$ solution applied vaginally. In the present study, by administration of polycarbophil hydrogel containing LHRH the ovulation inducing activity was 3.3 times greater than solution. These results indicate not only peptidase inhibitor but also polycarbophil hydrogel significantly improved the absorption of this drug. The results of this study would provide the feasibility as a rational dosage form for improving bioavailability and self administration of this hydrogel by the vaginal application.

• Microbiology and Biotechnology Letters
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• v.23 no.6
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• pp.730-736
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• 1995

The solubilization and proteolytic process of $\delta $-endotoxin was analvsed to compare the biochemical property of the toxin isolated from B. thuringiensis subsp. sotto. The purified crystals were dissolved in 50 mM carbonate buffer containing 10 mM dithiothreitol at pH 10 for various times. The electrophoretic pattern showed that a rapid disappearance of 138 kDa protein band. This disappearance of protein with high molecular weight was accompanied by the appearance of new protein fragment with 104 kDa, 60 kDa, and 25 kDa. For proteolvtic processing, the soluble crystals were digested with trypsin for various times. The soluble crystal protein of 104 kDa was completely disappeared. However, the protein fragment of 60 kDa and 25 kDa still remained after complete proteolysis. The comparative immunoblot analysis showed that the antiserum against intact crystals showed strong immunoreactivity to the homologous inclusion protein of 138 kDa, 104 kDa, and 25 kDa, and to the intact spores of 221 kDa and 138 kDa, but not to the vegetative cell homogenate. The sera against crystals and spores had no immunoreactivity to the vegetative cell homogenate.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.6
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• pp.885-893
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• 2001

This review summarizes some recent research into ways of improving the productivity of ruminal fermentation by increasing protein flow from the rumen and decreasing the breakdown of protein that results from the action of ruminal microorganisms. Proteinases derived from the plant seem to be of importance to the overall process of proteolysis in grazing animals. Thus, altering the expression of proteinases in grasses may be a way of improving their nutritive value for ruminants. Inhibiting rumen microbial activity in ammonia formation remains an important objective: new ways of inhibiting peptide and amino acid breakdown are described. Rumen protozoa cause much of the bacterial protein turnover which occurs in the rumen. The major impact of defaunation on N recycling in the sheep rumen is described. Alternatively, if the efficiency of microbial protein synthesis can be increased by judicious addition of certain individual amino acids, protein flow from ruminal fermentation may be increased. Proline may be a key amino acid for non-cellulolytic bacteria, while phenylalanine is important for cellulolytic species. Inhibiting rumen wall tissue breakdown appears to be an important mechanism by which the antibiotic, flavomycin, improves N retention in ruminants. A role for Fusobacterium necrophorum seems likely, and alternative methods for its regulation are required, since growth-promoting antibiotics will soon be banned in many countries.

• Journal of Microbiology and Biotechnology
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• v.17 no.6
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• pp.897-904
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• 2007

The aim of this paper is to discuss the methodology of our investigation of the dynamics of protein degradation and the total in situ protealytic activity in meso/eutrophic, eutrophic, and hypereutrophic freshwater environments. Analysis of the kinetics and rates of enzymatic release of amino acids in water samples preserved with sodium azide allows determination of the concentrations of labile proteins $(C_{LAB})$, and their half-life time $(T_{1/2})$. Moreover, it gives more realistic information on resultant activity in situ $(V_{T1/2})$ of ecto- and extracellular proteases that are responsible for the biological degradation of these compounds. Although the results provided by the proposed method are general y well correlated with those obtained by classical procedures, they better characterize the dynamics of protein degradation processes, especially in eutrophic or hypereutrophic lakes. In these environments, processes of protein decomposition occur mainly on the particles and depend primarily on a metabolic activity of seston-attached bacteria. The method was tested in three lakes. The different degree of eutrophication of these lakes was clearly demonstrated by the measured real proteolytic pattern and confirmed by conventional trophic state determinants.