• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.6
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• pp.766-772
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• 2007

The enzymatic hydrolysate of skipjack tuna cooking drip with good functionality was prepared by incubation with Alcalase for 30 min. For the preparation of functional seasoning sauce with enzymatic hydrolysate (SSE), the additives, such as concentrated enzymatic hydrolysate (100 mL), yeast extract powder (0.7 g), lactose (0.4 mL), liquid smoke (0.3 g) and sea tangle powder (1.4 g), were added to the enzymatic hydrolysate and boiled before filtration. The proximate composition of SSE was 11.8% for crude protein, 5.77 for pH and 11.9% for salinity. The SSE was higher in the crude protein, while lower in the salinity than commercial seasoning sauce. ACE inhibitory activity ($IC_{50}$) and antioxidative activity (PF) of SSE were 6.2 mg/mL and 1.14, respectively, which were superior to those (9.9 mg/mL in IC50 and 0.91 in PF) of commercial seasoning sauce. The free amino acid content (1,905.2 mg/100 mL) and taste value (58.65) of SSE were higher than in those (712.7 mg/100 mL and 34.30, respectively) of commercial sauce. Total amino acid content of SSE (10,965 mg/100 mL) was higher than that (4,818 mg/100 mL) of commercial sauce. The major amino acids of SSE were glutamic acid (12.2%), proline (11.0%), histidine (10.7%) and glycine (9.9%). The results suggested that SSE could be commercially sold.

• YAKHAK HOEJI
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• v.41 no.6
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• pp.714-717
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• 1997

Stereoselective synthesis of the optically active bicyclo [4.2.0] octanone 5 was accomplished using intramolecular olefin-keteniminium salt[2+2]cycloaddition of the amide 4 as a key step. This important chiral synthon was prepared starting from readily available L-glutamic acid via an efficient 8-step sequence.

• Journal of Life Science
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• v.18 no.12
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• pp.1723-1727
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• 2008

Chlorella sp. CMS-1 strain was isolated from the outdoors cultivation pools in Culmansa Co., Ltd. This strain was found to be a rounded type of 3 ${\mu}m$. Phylogenetic analysis by the 18S rRNA sequencing using isolated strain is most similar to Chlorella sp. IFRPD 1018 gene at the level of nucleotide sequence identity at 99%. Accordingly, the isolated Chlorella strain was named as Chlorella sp. CMS-1 based on its morphological and phylogenetic properties. The concentrations of crude protein and fat were 59% and 0.01%, respectively. Major compositional amino acids (mg%) were glutamic acid 6.21, alanine 5.76, aspartic acid 5.44%, glycine 4.29%, and threonine 3.09% and major free amino acids (mg%) were ${\gamma}$-aminobutyric acid (GABA) 7.13%, L-alanine 1.44%, L-glutamic acid 0.90, L-leucine 0.26% and L-glycine 0.20%. The concentrations of major minerals were P 2.25%, K 2.25%, Na 1.09%, Mg 0.63%, and Ca 0.28%.

• Microbiology and Biotechnology Letters
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• v.51 no.1
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• pp.53-58
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• 2023

The glutamic acid producing strain for development savory taste enhancing foods was identified the possibility through application into soybean fermentation. To check the effects on glutamic acid production during soybean fermentation, Lactococcus lactis HY7803 was introduced as a starter. The soybean samples were analyzed on days 0, 7, 14 and 21. The numbers of bacteria decreased gradually, while the content of amino-type nitrogen increased during fermentation in the soybean with L. lactis HY7803. Glutamic acid content in soybeans with L. lactis HY7803 increased from 114.99 ± 9.37 pmol/ul on day 0 to 138.14 ± 1.76 pmol/ul on day 21, showing an overall higher amino acid content than soybeans without L. lactis HY7803 and similar content to soybeans with Aspergillus oryzae SNU-G. It was clearly distinguished through principal component analysis. Consequently, our results indicate that L. lactis HY7803 is available as a fungus replacement and may be a good starter strain for enhancing savory taste in vitro as well as soybean fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.209-215
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• 2007

The functional sauce from shrimp byproducts (heads, shells and tails) was prepared and examined for its characterization. The results of volatile basic nitrogen (VBN) suggested that shrimp byproducts were suitable materials for preparing functional sauce. The shrimp hydrolysate, which was incubated with Alcalase for 30 min, showed excellent yield and ACE inhibitory activity. The concentrated sauce from shrimp byproduct was high in crude protein, while low in VBN content and salinity when compared to commercial shrimp sauce. The total amino acid content (23,095.2 mg/100 mL) of concentrated sauce from shrimp byproduct was higher than that (4,582.5 mg/100 smL) of commercial shrimp sauce; also, the major amino acids were glutamic acid, aspartic acid, arginine and lysine. The free amino acid content and taste value of concentrated sauce from shrimp byproduct were 2,705.5 mg/100 mL and 81.0, respectively. The results on the taste value of concentrated sauce from shrimp byproducts suggested that the major taste active compounds among free amino acids were glutamic acid and aspartic acid.

• Journal of the Korean Society of Food Science and Nutrition
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• v.7 no.1
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• pp.7-13
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• 1978

Changes in contents of general components of comfrey cultured in Korea were experimented and amino acids were analyzed by thin layer chromatography (T.L.C.) and gas chromatography (G.L.C.). The results obtained were as follows; 1. General components of comfrey such as moisture, fat, protein, carbohydrate, crude fiber and total ash were 13.20, 2.22, 22.30, 37.62, 9.38 and 15.06%. respectively, after 60 days growth. 2. The root of comfrey after 60 days contained 6.03% of alanine, 2.24% valine, 10.77% arginine, 2.96% glycine, 4.08% histidine. 1.54% isoleucine, 0.58% cystein, 1.72% methionine, 7.55% aspartic acid, 7.81% glutamic acid and 4.65% lysine in the gas chromatographic analysis of amino acid composition 3. The crude protein was decreased after 60 days of growth whereas the contents of carbohydrate, crude fiber and total ash were increased. 4. The total amount of amino acids in root was greater than that in leaf of comfrey.

• Korean Journal of Microbiology
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• v.54 no.3
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• pp.266-271
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• 2018

Effect of plasmid curing of Acinetobacter sp. B-W on the production of siderophore from glutamic acid as both carbon and nitrogen sole sources was investigated. Plasmid cured mutant of strain B-W lost the ability to produce siderophore from glutamic acid at $28^{\circ}C$. Transformant E. coli $DH5{\alpha}$ harboring 20 kb plasmid, that was isolated from wild type of strain B-W produced siderophore from glutamic acid as both carbon and nitrogen sole sources at $28^{\circ}C$, but, not at $36^{\circ}C$. Production of siderophore from glutamic acid by transformant E. coli $DH5{\alpha}$ was completely inhibited by $10{\mu}M\;FeCl_3$. In previous report, catechol nature of siderophore produced from glutamic acid by strain B-W was detected by Arnow test. The siderophore produced from glutamic acid by transformant E. coli $DH5{\alpha}$ was also catechol type. Rf value of siderophore produced from transformant E. coli $DH5{\alpha}$ grown in medium glutamic acid as both carbon and nitrogen sole sources at $28^{\circ}C$ was 0.32 in butanol-acetic acid-water (12:3:5) as developing solvent. Rf value of the siderophore was the same with that of wild type of strain B-W. Thus a single plasmid of 20 kb seemed to be involved in the production of siderophore from glutamic acid.

• Journal of Life Science
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• v.31 no.5
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• pp.520-526
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• 2021

Microbial protein is one of the sources of protein in the rumen and can also be the source of glutamate production. Glutamic acid is used as fuel in the metabolic reaction in the body and the synthesis of all proteins for muscle and other cell components, and it is essential for proper immune function. Moreover, it is used as a surfactant, buffer, chelating agent, flavor enhancer, and culture medium, as well as in agriculture for such things as growth supplements. Glutamic acid is a substrate in the bioproduction of gamma-aminobutyric acid (GABA). This review provides insights into the role of glutamic acid and glutamic acid-producing microorganisms that contain the glutamate decarboxylase gene. These glutamic acid-producing microorganisms could be used in producing GABA, which has been known to regulate body temperature, increase DM intake and milk production, and improve milk composition. Most of these glutamic acid and GABA-producing microorganisms are lactic acid-producing bacteria (LAB), such as the Lactococcus, Lactobacillus, Enterococcus, and Streptococcus species. Through GABA synthesis, succinate can be produced. With the help of succinate dehydrogenase, propionate, and other metabolites can be produced from succinate. Furthermore, clostridia, such as Clostridium tetanomorphum and anaerobic micrococci, ferment glutamate and form acetate and butyrate during fermentation. Propionate and other metabolites can provide energy through conversion to blood glucose in the liver that is needed for the mammary system to produce lactose and live weight gain. Hence, health status and growth rates in ruminants can be improved through the use of these glutamic acid and/or GABA-producing microorganisms.

• Journal of Applied Biological Chemistry
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• v.54 no.1
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• pp.1-6
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• 2011

${\gamma}$-PGA(poly-${\gamma}$-glutamic acid) is an unusual anionic polypeptide that is made of D- and L-glutamic acid units connected by amide linkages between ${\alpha}$-amino and ${\gamma}$-carboxylic acid groups. ${\gamma}$-PGA has been isolated from many kinds of organisms. Many Bacillus strains produce ${\gamma}$-PGA as a capsular material of an extracellular viscous material. It is safe for eating as a viscosity element of fermented soybean products such as Chungkookjang and Natto. It is biodegradable, edible and nontoxic toward humans and the environment and its molecular weight varies from ten thousand to several hundred thousand depending on the kinds of strains used. Therefore, potential applications of ${\gamma}$-PGA and its derivatives have been of interest in the past few years in a broad range of industrial fields such as food, cosmetics, medicine, water-treatment, etc. In this study, a bacterium, Bacillus subtilis GS-2 isolated from the Korean traditional seasoning food, Chungkookjang could produce a large amount of ${\gamma}$-PGA with high productivity and had a simple nutrient requirement. Based on carbon utilization pattern and partial 16S rRNA sequence analysis, the GS-2 strain was identified as B. subtilis. The determination of purified ${\gamma}$-PGA was confirmed with thin layer chromatography (TLC), high performance liquid chromatography (HPLC), fourier transform infrared (FT-IR) spectra, and $^1H$-nuclear magnetic resonance ($^1H$-NMR) spectroscopy.

• Microbiology and Biotechnology Letters
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• v.14 no.6
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• pp.487-493
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• 1986

Lactobacillus helveticus YM-1and Streptococcus lactis Ml$_3$ were inoculated together in reconstituted non-fat skim milk medium, and then their proteolytic activity and stimulatory compound for acid production were investigated. Significant difference between Lactobacillus helveticus YM-1 and Streptococcus lactis Ml$_3$was observed in the proteolytic activities. The proteolytic activity of Lactobacillus helveticus YM-1 and Streptococcus lactis Ml$_3$ was 105 $\mu\textrm{g}$/$m{\ell}$ and 30 $\mu\textrm{g}$/$m{\ell}$ when converted the amounts of hydrolysates of milk protein determined by Folin Ciocaleau phenol method into their tyrosine equivalent Stimulatory compounds in cell-free filtrate of Lactobacillus helveticus YM-1were identified as peptide with a molecular weight of approximately 4, 300 for the acid production by Streptococcus lactis Ml$_3$. Some kinds of amino acids, such as histidine, lysine, arginine and glutamic acid, were rich in acid hydrolysates of peptide. Among amino acids, histidine, glutamic acid and phenylalanine stimulated acid production, on the contrary isoleucine inhibited.