• Human Ecology Research
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• v.60 no.2
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• pp.303-315
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• 2022

The physicochemical properties of traditional kochujang added with naked oat flours (0, 5, 10, 15%) were periodically examined during fermentation for 20 weeks at 25℃(± 2 ℃). The proximate composition of roasted naked oat flours were as follows: water 0.67%, ash 1.63%, fat 10.37%, protein 13.63%, carbohydrates 73.70%. The water contents of traditional kochujang added with naked oat flours decreased gradually according to the addition level. The pH of traditional kochujang added with naked oat flours increased according to the added level, whereas pH decreased gradually during fermentation. The acidity was opposite to pH. The L (lightness), a (redness) and b (yellowness)-values of samples increased according to the amount of added naked oat flours, whereas they decreased gradually during fermentation. The salinity and sweetness of samples decreased according to the amount of added naked oat flours. Amino acid composition of traditional kochujang added with naked oat flours was higher than that of the control during fermentation. Aspartic acid, alanine, leucine, and arginine were high in the case of traditional kochujang added with 0% naked oat flours, and aspartic acid, leucine, alanine, proline. And arginine were high in the case of traditional kochujang added with 15% naked oat flours. The dietary fiber content was 5.38g/100g in the case of 0% addition and 5.75g/100g in the case of 15% addition. As a result of the above results, it was found that the physicochemical properties of traditional kochujang added with naked oat flours could be improved, and the possibility of developing a traditional kochujang beneficial to health was confirmed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.4
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• pp.326-335
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• 1988

In order to increase the availability of filefish scrap, the ordinary and low salt sauce were prepared, and identified their taste compounds in their products. To process the filefish scrap sauce, chopped filefish scrap was mixed with koji, 25% brine, slat and glucose (25.0 : 65.0 : 12.5 : 7.0, w/w) and fermented at $25{\pm}4^{\circ}C$ for 120 days. The same process was also carried out to process the low salt sauce adding sorbitol, lactic acid and ethyl alcohol (7.0 : 0.7 : 9.0. w/w) instead of salt. While amino nitrogen and volatile basic nitrogen(VBN) of products were decreased, pH and reducing sugar were increased all alone the fermentation period. The major free amino acids of products at final stage of fermentation were glutamic acid, alanine, leucine, lysine and aspartic acid. And the contents of total amino acid in the ordinary and low salt sauce were 4126.6(mg/100m1 sauce), 4519.5(mg/100m1 sauce) after fermentation. Hypoxanthine was revealed as the major constituent among nucleotides and their related compounds through fermentation. Free amino acid-N in the filefish scrap sauces were from 56.3%(ordinary) to 60.7%(low salted) of extractive nitrogen. From the sensory evaluation, the quality of products from filefish scrap sauce were almost equal to sold soy sauce on the market.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.546-551
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• 2002

Nutritional composition and phenolic compounds of raw propolis collected from falseacacia (Robinia pseudoacacia L.) and chestnut tree (Castanea crenata), and their 70% ethanol extracts of propolis (EEP) were analyzed. Propolis had high crude lipid content, but no significant differences in general compositions in terms of collection area and plant origins. Mineral contents varied greatly depending on the plant origins, with falseacacia propolis showing the highest mineral content. Sixteen amino acids were analyzed, among which aspartic acid content was the highest at $328.4{\sim}410.6\;mg%$ and methionine the lowest at $0{\sim}21.1\;mg%$. Extraction yield for EEP was relatively high at $64.2{\sim}81.9%$, and total polyphenol and flavonoid contents were $13.9{\sim}23.7$ and $8.6{\sim}10.8%$, respectively. HPTLC and HPLC analysis on the phenolic compounds revealed the overall chromatographic patterns were almost equal, showing similar polyphenol compositions between the propolis. About 16 peaks were identified by HPLC analysis, among which 6 peaks of p-hydroxy benzoic acid, caffeic acid, ferulic acid, benzoic acid, cinnamic acid, and chrysin were identified.

• Journal of Applied Biological Chemistry
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• v.56 no.2
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• pp.89-93
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• 2013

Gamma-aminobutyric acid (GABA) aminotransferase (gabT) and succinic semialdehyde dehydrogenase (gabD) genes from Pseudomonas fluorescens KCCM 12537 were cloned into a single pETDuet-1 vector and co-expressed in Escherichia coli BL21(DE3) simultaneously. The mixture of both enzymes, called GABase, is the key enzyme for the enzymatic analysis of GABA. The molecular mass of the GABA aminotransferase and succinic semialdehyde dehydrogenase were determined to be 52.8 and 46.7 kDa following computations performed with the pI/Mw program, respectively. The GABase activity between pH 6.0 and 9.0 for 24 h at $4^{\circ}C$ remained over 75%, but under pH 6.0 decreased rapidly. The GABase activity between 25 and $35^{\circ}C$ by the treatment at pH 8.6 for 30 min remained over 80%, but over $35^{\circ}C$ decreased rapidly. When the activity against GABA was defined as 100%, the purified GABase activity against 5-aminovaleric acid having a similar structure to GABA showed 47.7% and GABase activity against ${\beta}$-alanine, ${\varepsilon}$-amino-n-caproic acid, $_L$-ornithine, $_L$-lysine, and $_L$-aspartic acid showed between 0.3 to 2.3%. The GABA content was analyzed with this co-expressed GABase, compared with the other GABase which was available commercially. As a result, the content of GABA extracted from brown rice, dark brown rice, and black rice were $26.4{\pm}3.5$, $40.5{\pm}4.7$ and $94.7{\pm}9.3{\mu}g/g$, which were similar data of other GABase in the error ranges.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.1
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• pp.75-82
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• 1999

The hydrolysate of desalinated tuna boiled extract (TBE) were prepared by continuous hydrolysis of TBE using a membrane reactor. TBE and tuna boiled extract hydrolysate (TBEH) were isolated depending on molecular weights. The major molecular weight distributions of TBEH-l0K, TBEH-5K and TBEH-lK were 9,800Da, 3,000Da and 990Da, respectively. The amounts of nucleotides and their related compounds of TBE were 3.47 $\mu$mole/g AMP, 23.75 $\mu$mole/g IMP, 9.07 $\mu$mole/g inosine and 1.89 $\mu$mole/g hypoxanthine. Total content of amino acids having desirable taste (glycine, glutamic acid, alanine, proline, aspartic acid, serine) was about $63\%$ of total amino acid from TBE and about $62\%$ from TBEH. The natural seasoninings were prepared with TBE and TBEH. From the results of sensory evaluations, complex seasoning containing TBEH-1K was almost equal to the shellfish complex seasoning obtained from the market. The mixed sauce which was made by mixing of $50\%$ TBEH sauce and $50\%$ fermented soy sauce was similar to the tradition soybean sauce in product quality and it showed the possibility to be used for the substitute product for acid hydrolyzed soysauce.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.3
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• pp.257-264
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• 2004

The quality changes of the extracts of salt-fermented Ammodytes personatus during the storage were examined at 1 month interval during 3 months fermentation period. To prepare the extracts of Ammodytes personatus, 17%, 20% and 25% salt were added respectively and then stored for 3 months at room temperature and then extracted with hot water. During the storage, moisture and lipid contents of the samples decreased, but the crude protein contents increased gradually. On the other hand, ash content and pH showed little changes during the fermentation storage. After 6 months fermentation, the extracts of salt-fermented Ammodytes personatus were rich in free amino acids, such as glutamic acid, alanine, lysine, leucine, isoleucine, valine and aspartic acid in the order. As the fermentation progressed, the fish odor, turbidity, salty taste, savory flavor and overall preferences were similar to those of Ammotlytes personatus sauce in the market. The total cell numbers were 450∼570 cfu/mL at 0 day, but there were none revealed during the fermentation.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.714-719
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• 2001

An interest in traditional foods is growing in an effort to preserve dietary culture in Korea. Blue crab preserved in soy sauce, one of the Korean traditional foods is especially popular in summer and is produced in the Jeollanam-do province, Korea. However, there has been no report on processing of the blue crab. The objective of this research is to investigate changes of nutritional composition in blue crab preserved in soy sauce. Moisture content was a little higher in FBC (Fresh Blue Crab) than in PBC (Preserved Blue Crab) and ash content was greatly higher in PBC than in FBC. Salt content was 1.50% in FBC and 7.89% in PBC. The amount of free sugars in FBC was very low but was increased after preserved using soy sauce, especially of fructose significantly. After preserved, the pH of blue crab was also increased. The contents of most total amino acids in blue crab were decreased after preserved, but free amino acids were increased. Major total amino acids were glutamic acid, arginine and aspartic acid in two samples and major free amino acids were arginine, proline and alanine. Fatty acid content was decreased after preserved and major fatty acids were palmitic acid (16 : 0), oleic acid (18 : l), eicosapentaenoic acid (20 : 5) and docosahexaenoic acid (22 : 6).

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1379-1383
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• 2010

Nectarine beverage treated with cellulase and pectinase enzymes was measured for mineral contents, total flavonoids, and free amino acids and DPPH radical scavenging effect, nitrite scavenging effect. Total flavonoid contents of the no treatment, treated with pectinase, with cellulase, and with both measured 0.146 mg/mL, 0.167 mg/mL, 0.148 mg/mL and 0.171 mg/mL, respectively. DPPH was measured as 13.42% with no treatment and more than 28.98% with enzyme treatments. Nitrite scavenging effect with no treatment was 79% at pH 1.2. Whereas, it was measured above 90% while treated with enzymes at pH 1.2. And also, the nitrite scavenging effect was slightly higher at pH 3.0, pH 4.0 and pH 6.0 than no treatment. Results of free amino acids analysis revealed that, aspartic acid, serine, alanine, $\gamma$-aminobutylic acid, and glutamic acid were present with the amount ranging from 86.71% to 94.14% from total detected free amino acids. Ornithine and taurine were also observed from the beverages. The mineral contents, nitrogen element (T-N) of enzyme treatment of nectarine beverages were measured slightly higher than T-N of no treatment, however, the $P_2O_5$ was similar. Moreover, CaO, MgO and $K_2O$ in the beverages were measured above 45 mg/L, 85 mg/L and 2,133 mg/L, respectively.

• Journal of Microbiology and Biotechnology
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• v.4 no.3
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• pp.204-209
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• 1994

The synthesis of N-(benzyloxycarbonyl)-L-aspartyl-L-phenylalanine methylester (Z-APM), a precursor of aspartame, from N-(benzyloxycarbonyl)-L-aspartic acid (Z-Asp) and L-phenylalanine methylester hydrochlolide($L-PM\cdot HCI$) was investigated in a saturated-ethylacetate single phase system using immobilized thermolysin. Among the various supports tested, glyceryl-CPG was found to be most efficient for retaining enzyme activity. The enzyme immobilized onto glyceryl-CPG also showed the highest activity for Z-APM synthesis in saturated ethyl acetate. Z-APM conversion yield in saturated ethylacetate was half of that obtained in an ethyl acetate-buffer two-phase system under the same reaction conditions. However, as the mole ratio of $L-PM \cdot HCI$ to Z-Asp was increased to 4.0, the conversion yield reached 95 %. When continuous synthesis of Z-APM was canied out in a plug flow reactor (PFR) with 80 mM of L-PMㆍHCI and 20 mM of Z-Asp in saturated ethylacetate (pH 5.5), more than 95 % of Z-Asp was converted to Z-APM with a space velocity of 1.16 $hr^{-1} at 40^{\circ}C$. Although the operational stability in PFR was reduced rapidly, more than 80% of initial activity was maintained in CSTR even after a week of operation.

• Journal of Life Science
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• v.14 no.6 s.67
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• pp.931-937
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• 2004

The present investigation was carried out to determine the qualitative difference between 4 varieties of perilla leaves cultivated Miryang area, particularly focusing on the amino acid composition and flavor compounds. Aspartic acid, glutamic acid, glycine, alanine, arginine, and threonine were the major amino acids, and tyrosine and cysteine and methionine containing sulfur were detected as little amount in protein of all perilla leaves. All perilla leaves contained about 34 kinds of free amino acids, and the major free amino acids were same as the protein bound amino acids. However, no significant difference among 4 varieties of perilla leaves was observed in the profiles of protein bound and free amino acids composition. Flavor compounds analyzed by GC-MSD following to extraction of flavor by SDE (Simultaneous Steam Distillation-Extraction) were detected as 51 kinds from 'Leafy perilla 1', 47 kinds from 'Yupsil perilla', 46 kinds from 'Miryang 9' and 'YCPL. The major volatile compound was perilla ketone, its concentration was $145.75\;{\mu}g/g$ in 'Miryang 9', $187.00\;{\mu}g/g$ in 'YCPL', $301.59\;{\mu}g/g$ in 'Leafy perilla l' and $551.42\;{\mu}g/g$ in 'Yupsil perilla', but the other flavor compounds, 3-hexen-l-ol, trans-2-hexenal, $\beta-caryophyllene,\;\alpha-farnesene$ and etc, were less than $20\;{\mu}g/g$.