• Korean Journal of Microbiology
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• v.43 no.4
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• pp.304-310
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• 2007

Bacillus cereus 1-1 strain produced 2 mM of ALA in the aerobic dark condition without any inhibitor like levulinic acid. The optimum culture conditions for the ALA production were that preculture and main culture were continued for 18 hr in TCY medium, and 16 mM of organic acids like acetic acid were added at the late log phase when the pH was 6.8. And the addition of 0.3% glucose was effective at the beginning of the main culture. ALA production was continued for more than 8 hr by the addition of glutamic acid instead of acetic acid, and was inhibited by addition of $40\;{\mu}M$ gabaculine seriously. These results confirmed that B. cereus 1-1 strain produced ALA through C-5 pathway.

• Korean journal of food and cookery science
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• v.14 no.3
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• pp.250-254
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• 1998

A variation of free sugar and amino acid contents of pears during the ripening period was determined by HPLC and amino acid analyzer. The research results are as follws: Fructose, glucose and sucrose were present in the pears. The contents of fructose was the highest, followed by glucose and sucrose in order. The contents of total sugar in Shingo and Youngsan was similar, but the contents of frucose in Shingo was lower and the contents of sucrose was higher than that of Youngsan (p＜.001). During the ripening period, the contents of fructose and glucose gradually increased during the harvesting season and then somewhat decreased. The contents of sucrose increased continually, while the contents of total free sugar reached the maximum during the harvesting season, it was 10.41%, 10.29% in Shingo and Youngsan and then decreased gradually. The contents of total free amino acid in Shingo was higher than that of Youngsan. A variation ratio and the composition of amino acid in Shingo and Youngsan during the ripening period didn＇t make a significant difference. The major free amino acid of the pears was in the order of aspartic acid, serine, threonine, histidine, glutamic acid, valine, arginine, and alanine. During the ripening period, aspartic acid, threonin, serine, methionine, isoleucine, leucine, histidine, and Iysine increased gradually. Glutamic acid, alanine, valine, arginine didn＇t show much change. The contents of total free amino acid increased during the ripening period.

• Journal of Dairy Science and Biotechnology
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• v.26 no.2
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• pp.39-43
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• 2008

EMC have a similar enzymatic reaction to cheese, but the EMC produce the stronger flavors than cheese by much more enzymatic reaction. It is important to find appropriate enzyme in order to develop these kind of superior EMC. Calf PGE is more suitable than that of kid and lamb to develop the mild cheese flavors. Especially, it was known that animal esterase and peptidase were more benefit than microbial enzyme for Cheddar cheese flavors. On the Cheddar and Swiss cheese, EMC flavors were much more 3 times than the cheese flavors. In the ratio of each component, butyric acid, myristic acid, palmitic acid and oleic acid were high in free fatty acid, and glutamic acid, valine, leucine and lysine were high in free amino acid of the Cheddar EMC.

• Applied Biological Chemistry
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• v.35 no.3
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• pp.210-217
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• 1992

A photosynthetic bacterium strain KUP-74 producing high amount of S-amino-levulinic acid(ALA) was isolated from soils, which was identified as Rhodocyclus gelatinosus. After 10 days cultivation under anaerobic-light condition at $30^{\circ}C$, 4 Klux and pH 6.8, 5 mg/l of ALA was formed extracellularly. ALA productions were increased up to 8 mg/l and 12 mg/l in cell cultivations either by the addition of 0.5% glycerol (v/v) or 10 mM of glycine and succinic acid, respectively, using Lascelles basal medium eliminated L-glutamic acid. By cultivation in the presence of 30 mM each D,L-glutamic acids and D,L-glutamines the yield of ALA showing a late induction phenomenon was reached the maximum value of 21 mg/l. Different culture times were needed to generate maximum ALA yields by the addition of initial precursors of $C_4$ and $C_5$ pathways in basal medium, as being 107 h and 262 h, respectively. 40 mg/l yield of ALA was observed by cell cultivation with the basal medium containing each 10 mM levulinic acid(LA) and glycine simultaneously.

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.304-308
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• 2007

This research was conducted to investigate the changes in quality characteristics of meju made with 24-hour germinated soybeans according to fermentation time. The study confirmed that the amino nitrogen content immediately after soaking was 15.5 mg%, and the content rapidly increased in the beginning of the germination process and continued to increase to 312.9 mg% by 48 hours of fermentation. The number of fungi in the whole soybean meju made with 24-hour germinated soybeans was higher than the numbers of bacteria and yeast since the Aspergillus oryzae was inoculated artificially. The content of organic acids, in which the amount of citric acid was highest followed by tartaric acid and malic acid, increased with the fermentation process. The level of free amino acids in the whole soybean meju made from the 24-hour germinated soybeans increased rapidly with fermentation. The free amino acid content after 48 hours of fermentation (2,513.5 mg%) was 5.7 times higher than the content of the soaked germinated soybeans. The content of glutamic acid was highest followed by aspartic acid, lysine, leucine, and proline. The ratio of glutamic acid to the total free amino acids at 48 hours fermentation was 21.2% for the whole soybean meju. It was confirmed that the total isoflavone content, in which the content of genistein was highest followed by daidzein and glycitein, increased at the beginning of the fermentation process, but did not change thereafter.

• Applied Biological Chemistry
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• v.49 no.1
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• pp.35-42
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• 2006

This study was conducted to find effective components on taste of kanjang made with barley bran. The result of stepwise multiple regression analysis with transformation of variables was that the 70.1% and 80.8% of taste of barley kanjang could be explained at step 6 and step 15, respectively, calculated from absolute value. And, the 83.0% and 84.3% of taste of barley kanjang was explained at step 6 and step 15, respectively, calculated from relative value transformed with logarithm. The contributing proportion of the ${\alpha}-ketoglutaric$ acid was the highest followed by citric acid, lavulinic acid and glutamic acid computed from absolute value, and the ${\alpha}-ketoglutaric$ acid was the highest followed by fructose, glutamic acid and valine calculated from relative value trans-formed with logarithm.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.1
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• pp.48-52
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• 1993

To furnish basic data for the utilization of leaf mustard as a raw material of salted and fermented vegetable food, major chemical compositions of Dolsan Leaf Mustard (DLM) were investigated. The moisture and ash contents of DLM were 87.5% and 1.4%, respectively. Compared with other Korean traditional or Japanese leaf mustard, DIM contained more crude protein (3.8%) but less crude fat (0.3%) and crude fiber (1.3%). As an alkali food, leaf and leat stalk had pH of 5.7 and 5.8, titratable acidity of 687 and 318mg/100g and alkalinity of 2.5 and 5.2, respectively. The major free sugar in DLM was glucose and fructose was also detected in a small amount. The contents of total and reducing sugar in leaf and leaf stalk were 574, 352, 820 and 538mg%, respectively. Total amino acid contents of leaf and leaf stalk were 8.0 and 2.5% on wet basis. Although the amino acid compositions of leaf and leaf stalk were different each other, glutamic acid and proline were the major amino acids in both of the leaf and leaf stalk. Significantly higher amount (ca.10.3-fold) of free amino acid was present in leaf (3074mg%) than in leaf stalk (298mg%). Glutamic acid and aspartic acid were the major free amino acids and essential amino acid contents in leaf and leaf stalk were 869 and 68mg% being 22.9 and 28.3% of total free amino acids.

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.192-196
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• 1989

This experiment was carried out to compare the difference of lipid components, amino acid composition by size of sea eel. Large sea eel(length 57.5-60.0cm, weight 269.5-300.0g) was higher in moisture and crude protein content, and lower in crude lipid content than those of small sea eel(28.8-31.2cm, 39.5-43.6g). Total lipid(TL) of large and small sea eel were consisted of 89.7%, 93.3% neutral lipid, 8.9%, 5.2% phospholipid, and 1.4%, 1.5% glycolipid, respectively. In fatty acid composition of TL, large fishes revealed higher content in polyunsaturated fatty acids such as 20:5, 22:5, 22:6, while lower in saturates and monoenes such as 16:0, 16:1, 18:1 than those of small fishes. The major fatty acids of these fishes were generally 18:1, 16:0, 22:6, 16:1 and 20:5 in order. Total amino acid contents of large and small sea eel were 17022.7mg/100g, 15409.4mg/100g. And the main amino acids were aspartic acid, glutamic acid, isoleucine, leucine, lysine, arginine. Large fishes was higher in cystine, methionine, tyrosine, phenylalanine content, while lower in aspartic acid, glutamic acid than those of small ones.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1484-1490
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• 2006

This study was carried out to prepare spaghetti sauce with adductor muscle of pearl oyster (SSAM) and to compare with commercial spaghetti sauce (CSS). From the results of organic acid, pH, hunter color value and sensory evaluation, the optimal addition ratio of adductor muscle of pearl oyster was 11% based for preparing SSAM and reasonable $F_0$ value was about 4 min for keeping storage of SSAM. The proximate composition of SSAM was 69.8% for moisture, 3.7% for protein, 4.2% for crude lipid and 3.4% for crude ash. SSAM was superior in sensory flavor and texture to CSS. There was, however, no significant difference (p<0.05) in sensory color between CSS and SSAM. The total amino acid content (3,033.4 mg/100 g) of SSAM was higher than that (2,305.7 mg/100 g) of CSS and the major amino acids were aspartic acid, glutamic acid, leucine and lysine. Calcium and phosphorus contents in SSAM were 48.5 mg/100 g and 27.1 mg/100 g, respectively. Calcium level based on phosphorous was 1.78, which was a good ratio for absorbing calcium. The free amino acid content and taste value of SSAM were 989.4 mg/100 g and 141.04 mg/100 g, respectively These results suggested that the major taste active compounds among free amino acid were glutamic acid and aspartic acid.

• Korean Journal of Organic Agriculture
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• v.25 no.1
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• pp.171-185
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• 2017

${\gamma}$-aminobutyric acid (GABA) is a non-proteinogenic amino acid biosynthesized through decarboxylation of L-glutamic acid by glutamic acid decarboxylase. GABA is believed to play a role in defense against stress in plants. In humans, it is known as one of the major inhibitory neurotransmitters in the central nervous system, exerting anti-hypertensive and anti-diabetic effects. In this report, we wanted to enhance the GABA production from the barley leaf and corn silk by culturing them with lactic acid bacteria (LAB). The barley leaf and corn silk were mixed with various weight combinations and were fermented with Lactobacillus plantarum in an incubator at $30^{\circ}C$ for 48 h. After extracting the fermented mixture with hot water, we evaluated the GABA production by thin layer chromatography and GABase assay. We found that the fermented mixture of the barley leaf and corn silk in a nine to one ratio contained a higher level of GABA than other ratios, meaning that the intermixture and fermentation technique was effective in increasing the GABA content. We also tested several biological activities of the fermented extracts and found that the extracts of the fermented mixture showed improved antioxidant activities than the non-fermented extracts and no indication of cytotoxicity. These results suggest that our approach on combining the barley leaf and corn silk and its fermentation with LAB could lead to the possibility of the development of functional foods with high levels of GABA content and improved biological activities.