• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1350-1357
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• 2000

Traditional Kochujang was prepared adding horseradish or mustard powder to repress the gas formation which used to cause swelling problem during distribution. The koji for Kochujang was prepared by the strains which had high amylase and protease activities with superior flavor. The gas production from Kochujang during fermentation at $25^{\circ}C$ was ceased after stopping yeast growth completely by bactericidal components from $0.6{\sim}1.2%(w/w)$ of horseradish or mustard addition. Total viable bacterial count was not affected by adding horseradish or mustard. The amino type nitrogen content in Kochujang, which was one of the most important parameters in quality of Kochujang, increased continually during fermentation. The Kochujang fermented by P-2 isolate and added with mustard was significantly higher in amino type nitrogen content than other treatments after 120 days' fermentation. ${\alpha}-Amylase$ activity was very low while ${\beta}-amylase$ activity was high in Kochujang fermented by adding horseradish and mustard powder. The protease(acid and neutral) activities gradually increased by fermentation with no difference between treatments. The color and flavor were not different, but overall palatability of the Kochujang evaluated by sensory test showed significantly high rank in Kochujang fermented by P-2 isolate and with horseradish.

• Food Science and Preservation
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• v.20 no.6
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• pp.818-826
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• 2013

To evaluate the practical use of okara koji in soy sauce fermented with soybean koji, the okara koji was fortified with different contents (0, 50, and 100%) in soybean koji and then fermented for 90 days. The saltiness of the soy sauce was about 17.15~17.22%. The higher okara koji content showed lower net soluble solid contents of 8.73, 6.12, and 2.50%, as well as lower acidity levels of 1.09, 0.98, and 0.47%. The buffering capacity of the soy sauce decreased to 1.26-3.41 by adding higher okara koji. The protease activity was higher in the soy sauce with 50% orara koji and decreased with longer fermentation. Also, the tyrosine content peaked to 275.2 mg% after 90 days. ${\alpha}$-amylase showed higher activity in the soy sauces fortified with okara koji, which resulted in the highest total sugar and reducing sugar contents after 60 days. The total sugar and the reducing sugar in the soy source decreased after longer fermentation. The total free amino acid contents of the soy sources fortified with okara koji (0, 50, and 100%) were 41.68 mg/mL, 33.10 mg/mL, and 9.27 mg/mL, respectively. In particular, the glutamic acid contents of the three types of soy sauces were highest, and most amino acids, except for glutamine, increased during the fermentation for 90 days. The sensory evaluation, except of the saltiness and color, showed similar values in the soy sauces, except in the okara koji 100%. Thus, okara koji could be a valuable ingredient of traditional soy sauces. However, the 50% okara koji did not differ significantly from the others.

• Food Science and Preservation
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• v.22 no.5
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• pp.699-707
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• 2015

To improve the utilization of the domestic plant Salvia miltiorrhiza Bunge (Danshen), this study investigated changes in the physicochemical qualities of Danshen extracts obtained from low-temperature extraction using the enzymes amylase, cellulase, pectinase, and protease. Changes in the yield, pH, sugar content, and chromaticity were investigated. The changes were found to be highest in the amylase-treated extract with the following values: yield, 58.3%; pH, 6.04; sugar content, $5.97^{\circ}Brix$. With regard to antioxidant properties, Danshen extracts treated with amylase showed the highest DPPH and ABTS scavenging activities of 84.25% and 74.11% at 55 ppm. The total phenolic compound content was highest in the group subjected to enzyme treatment at $60^{\circ}C$. The salvianolic acid B level of the Danshen extract was the highest in the amylase-treated group, with a value of 3,002.6 mg/100 g. Cryptotanshinone level was the highest in the amylase- and protease-treated group with a value of 3.8 mg/100 g. Tanshinone I was the highest in the protease-treated group, with a value of 14.2 mg/100 g. The results showed that the indicator components of Danshen were detected as stable in the extracts after using amylase for low-temperature extraction; therefore, it would be possible to use Danshen industrially as a functional ingredient through mass production. Furthermore, the enzyme-treatment extraction could be utilized for a variety of natural products.

• Archives of Pharmacal Research
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• v.12 no.2
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• pp.88-93
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• 1989

In order to obtain some informations about the effect of molecular weight on the release rate of drug from drug carrier, two types of poly-L-glutamic acid (PLGA)-cytarabine (ara-C) conjugates, PLGA-ara-C:I and PLGA-ara-C:II, were synthesized using two types of PLGA having different average molecular weight, 43,000 and 77,800, respectively. The PLGA-ara-C conjugates were synthesized by mixed anhydride method and found to be covalently linked. Both types of conjugates charged negatively at biological pH. The pH-dependent release rate of ara-C was observed in both cases, and the release rate was accelerated in basic, acidic conditions (the k values were 0.015 $day^{-1}$ at pH 7.0, 0.024 $day^{-1}$ at pH 5.0, and 0.059 $day^{-1}$ at pH 9.0 in the case of PLGA-ara-C:I) and in the presence of pretense. The time required for the release of 16.5% of ara-C from PLGA-ara-C:I were 8 hr and 144 hr in the presence and absence of protease, respectively. Although both types of conjugates showed similar drug substitution ratio, they showed different release rates. Between the two types of conjugates, PLGA-ara-C:II showed the faster release rate (0.030 vs 0.042 $day^{-1}$ in pH 7.4 phosphate buffer solution at $37^{\circ}C$) and the smaller activation energy for the release of drug (12.5 vs 7.7 Kcal/mol) than PLGA-ara-C:I. The characteristic effect of molecular weight on the release rates of PLGA-ara-C conjugates suggests that the drug release rate might be effectively controlled over a prolonged period of time by the combined use of the different types of PLGA-ara-C conjugates having different molecular weights.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.2
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• pp.273-282
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• 2007

This study was carried out to compare the changes of nutrients, sensory and chemical properties of freeze-concentrated and evaporated milks during storage. For pasteurization, the freeze-concentrated milk containing 27% of total solid was treated with 150 rpm ozone for 5 min, and 99% of microflora was eliminated. Also, the activities of protease and lipase decreased 93.31% and 96.15%, respectively, and phosphatase showed negative activity. Total bacteria count was maintained below$2.0{\times}10^4$CFU/ml. During storage, TBA absorbance was lower in freeze-concentrated milk than that in the evaporated milk. The production of short-chain free fatty acids and free amino acids increased proportionally to the storage period in both samples. While the short-chain free fatty acid production was lower in the freeze-concentrated milk compared with that in the evaporated milk, the production of individual free amino acid was similar in both samples. In sensory evaluation, cooked flavor and color were much lower in the freeze-concentrated milk than that in the evaporated milk. Overall acceptability score was higher in the freeze-concentrated than the evaporated milk. Based on above results, ozone treatment for the freeze-concentrated milk pasteurization was positive at the elimination of microflora and enzyme inactivation. During storage, the freeze-concentrated sample minimized the change of color and TBA absorbance, the production of short-chain free fatty acid and vitamins than the evaporated milk. Therefore, the freeze-concentrated milk process in the present study resulted in the positive effect in minimizing nutrient loss and keeping quality of milk during storage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.4
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• pp.513-518
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• 2003

Three kind of apple kochujangs were prepared using different commercial meju (normal commercial product, two commercial product from Aspergilius sp. and Bacillus sp.) and investigated about characteristics. The contents of total free sugar were the highest, 22.43% in apple kochujang (II) after 10 week fermentation. The glucose was specially high ratio in apple kochujang (III). The contents of total amino acid were 107.53~401.52 mg% in apple kochujang (I), 108.69~441.19 mg% in apple kochujang (II) and 106.82~423.28 mg% in apple kochujang (III). From the sensory evaluation after 12 weeks, the scores for flavor preference and total acceptability were the highest in apple kochujang (III). There was no significant difference for taste and color in apple kochujangs.

• Microbiology and Biotechnology Letters
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• v.17 no.5
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• pp.440-446
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• 1989

Penicillium sp. CB-20 was selected for its strong polygalacturonase activity among various strains of molds found in soil. It was found that the production of polygalacturonase reached to maximum when on the wheat bran medium containing pectin as carbon source, the strain was cultured for 60 hours at 3$0^{\circ}C$. The enzyme was purified to 29.21 food by ammonium sulfate treatment, Sephadex G-25, G-15, G-150 gel filtration, DEAE-cellulose and DEAE-Sephadex A-50 ion-exchange chromatography. Yield of the enzyme purification was 2.31 %. When the purified enzyme was applied to sodium dodecyl sulfate polyacrylamide gel electrophoresis, the molecular weight was estimated 21, 000. The amino acid composition indicated relatively high contents of gultamic acid, glycine and histidine.

• Microbiology and Biotechnology Letters
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• v.29 no.1
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• pp.1-11
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• 2001

Lactic acid bacteria (LAB) are widely used for various food fermentation. With the recent advances in modern biotechnology, a variety of bio-products with the high economic values have been produced using microorganisms. For molecular cloning and expression studies on the gene of interest, E. coli has been widely used mainly because vector systems are fully developed. Most plasmid vectors currently used for E, coli carry antibiotic-resistant markers. As it is generally believed that the antibiotic resistance markers are potentially transferred to other bacteria, application of the plasmid vectors carrying antibiotic resistance genes as selection markers should be avoided, especially for human consump-tion. By contrast, as LAB have some desirable traits such that the they are GRAS(generally recognized as safe), able to secrete gene products out of cell, and their low protease activities, they are regarded as an ideal organism for the genetic manipulation, including cloning and expression of homologous and heterologous genes. However, the vec-tor systems established for LAB are stil insufficient to over-produce gene products, stably, limiting the use of these organisms for industrial applications. For a past decade, the two popular plasmid vectors, pAM$\beta$1 of Streptococcus faecalis and pGK12 theB. subtilis-E. coli shuttle vector derived from pWV01 of Lactococcus lactis ssp. cremoris wg 2, were most widely used to construct efficient chimeric vectors to be stably maintained in many industrial strains of LAB. Currently, non-antibiotic markers such as nisin resistance($Nis^{r}$ ) are explored for selecting recombi-nant clone. In addition, a gene encoding S-layer protein, slp/A, on bacterial cell wall was successfully recombined with the proper LAB vectors LAB vectors for excretion of the heterologous gene product from LAB Many food-grade host vec-tor systems were successfully developed, which allowed stable integration of multiple plasmid copies in the vec-mosome of LAB. More recently, an integration vector system based on the site-specific integration apparatus of temperate lactococcal bacteriophage, containing the integrase gene(int) and phage attachment site(attP), was pub-lished. In conclusion, when various vector system, which are maintain stably and expressed strongly in LAB, are developed, lost of such food products as enzymes, pharmaceuticals, bioactive food ingredients for human consump-tion would be produced at a full scale in LAB.

• Journal of Microbiology and Biotechnology
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• v.19 no.12
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• pp.1688-1694
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• 2009

A novel strain of fluorescent pseudomonad (PB-St2) was isolated from surface-sterilized stems of sugarcane grown in Pakistan. The bacterium was identified as Pseudomonas aurantiaca on the basis of 16S rRNA gene sequence analysis and results from physiological and biochemical characteristics carried out with API50 CH and QTS 24 bacterial identification kits. Assays using substrate-specific media for enzymes revealed lipase and protease activities but cellulase, chitinase, or pectinase were not detected. The bacterium was unable to solubilize phosphate or produce indole acetic acid. However, it did produce HCN, siderophores, and homoserine lactones. In dual culture assays on agar, the bacterium showed antifungal activity against an important pathogen of sugarcane in Pakistan, namely Colletotrichum falcatum, as well as for pathogenic isolates of Fusarium oxysporium and F. lateritium but not against F. solani. The antifungal metabolites were identified using thin-layer chromatography, UV spectra, and MALDI-TOFF spectra and shown to be phenazine-1-carboxylic acid (PCA), 2-hydroxyphenazine (2-OH-PHZ), and N-hexanoyl homoserine lactone (HHL) (assessed using only TLC data). The capacity of this bacterium to produce HCN and 2-OH-PHZ, as well as to inhibit the growth of C. falcatum, has not been previously reported.

• The Korean Journal of Physiology and Pharmacology
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• v.13 no.1
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• pp.15-22
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• 2009

This study was undertaken to elucidate the underlying mechanisms of ATP depletion-induced membrane transport dysfunction and cell death in renal proximal tubular cells. ATP depletion was induced by incubating cells with 2.5 mM potassium cyanide(KCN)/0.1 mM iodoacetic acid(IAA), and membrane transport function and cell viability were evaluated by measuring $Na^+$-dependent phosphate uptake and trypan blue exclusion, respectively. ATP depletion resulted in a decrease in $Na^+$-dependent phosphate uptake and cell viability in a time-dependent manner. ATP depletion inhibited $Na^+$-dependent phosphate uptake in cells, when treated with 2 mM ouabain, a $Na^+$ pump-specific inhibitor, suggesting that ATP depletion impairs membrane transport functional integrity. Alterations in $Na^+$-dependent phosphate uptake and cell viability induced by ATP depletion were prevented by the hydrogen peroxide scavenger such as catalase and the hydroxyl radical scavengers(dimethylthiourea and thiourea), and amino acids(glycine and alanine). ATP depletion caused arachidonic acid release and increased mRNA levels of cytosolic phospholipase $A_2(cPLA_2)$. The ATP depletion-dependent arachidonic acid release was inhibited by $cPLA_2$ specific inhibitor $AACOCF_3$. ATP depletion-induced alterations in $Na^+$-dependent phosphate uptake and cell viability were prevented by $AACOCF_3$. Inhibition of $Na^+$-dependent phosphate uptake by ATP depletion was prevented by antipain and leupetin, serine/cysteine protease inhibitors, whereas ATP depletion-induced cell death was not altered by these agents. These results indicate that ATP depletion-induced alterations in membrane transport function and cell viability are due to reactive oxygen species generation and $cPLA_2$ activation in renal proximal tubular cells. In addition, the present data suggest that serine/cysteine proteases play an important role in membrane transport dysfunction, but not cell death, induced by ATP depletion.