• Applied Biological Chemistry
• /
• v.43 no.1
• /
• pp.29-33
• /
• 2000

This study was carried out to investigate the effect of glutaminase added to Doenjang, Kochujang and Kanjang in manufacturing. The consequential changes of L-glutamic acid and amino nitrogen contents were periodically analysed during aging. L-Glutamic acid contents in Kochujang, Doenjang and Kanjang aged for 45 days increased to 671.8%, 298.1% and 193.4% with glutaminase and also increased to 363.1%, 159.2% and 35.7% as compared with those without glutaminase. The 0.01% addition of glutaminase to Kochujang made L-glutamic acid content increased more than 3 times. The increase ratio of amino nitrogen was 216%, 120.8% and 84.5% in Kochujang, Kanjang and Doenjang with glutaminase which aged for 45 days, respectively. The effect of glutaminase added was the greatest in Kochujang. It increased to 35.7%, 8.4% and 40.3% as compared with those without glutaminase. The results of sensory evaluation showed that the products were favorably affected in taste, flavor and acceptability by glutaminase added.

• Journal of Microbiology and Biotechnology
• /
• v.29 no.7
• /
• pp.1061-1070
• /
• 2019

In the present study, the optimization of poly(${\gamma}$-glutamic acid) (${\gamma}$-PGA) production by Bacillus sp. FBL-2 was studied using a statistical approach. One-factor-at-a-time method was used to investigate the effect of carbon sources and nitrogen sources on ${\gamma}$-PGA production and was utilized to select the most significant nutrients affecting the yield of ${\gamma}$-PGA. After identifying effective nutrients, response surface methodology with central composite design (CCD) was used to obtain a mathematical model to identify the optimum concentrations of the key nutrients (sucrose, $\text\tiny{L}$-glutamic acid, yeast extract, and citric acid) for improvement of ${\gamma}$-PGA production. The optimum amount of significant medium components appeared to be sucrose 51.73 g/l, $\text\tiny{L}$-glutamic acid 105.30 g/l, yeast extract 13.25 g/l, and citric acid 10.04 g/l. The optimized medium was validated experimentally, and ${\gamma}$-PGA production increased significantly from 3.59 g/l (0.33 g/l/h) to 44.04 g/l (3.67 g/l/h) when strain FBL-2 was cultivated under the optimal medium developed by the statistical approach, as compared to non-optimized medium.

• Food Science of Animal Resources
• /
• v.33 no.3
• /
• pp.377-389
• /
• 2013

Gamma-amino butyric acid (GABA) is a kind of pharmacological and biological component and its application is wide and useful in Korea specially, becoming aging society in the near feature. GABA is request special dose for the purposed biological effect but the production of concentrated GABA is very difficult due to low concentration of glutamic acid existed in the fermentation broth. To increase GABA concentrate using fermentation technology, high content of glutamic acid is required. For this reason, various strains which have the glutamic acid decarboxylase (GAD) and can convert glutamic acid to GABA, were isolated from various fermented foods. Most of GABA producing strains are lactic acid bacteria isolated from kimchi, especially added monosodium glutamate (MSG) as a taste enhancer. Optimizing the formulation of culture media and the culture condition, GABA conversion yield and amounts were increased. Finally GABA concentration of fermentation broth in batch or fed batch fermentation reached 660 mM or 1000 mM, respectively. Furthermore formulation of culture media for GABA production developed commercially. Many studies about GABA-rich product have been continued, so GABA-rich kimchi, cheese, yogurt, black raspberry juice and tomato juices has been also developed. In Korea many biological effects of GABA are evaluated recently and GABA will be expected to be used in multipurpose.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.12 no.4
• /
• pp.336-341
• /
• 1983

A study on the oxidation effect of some amino acids(glutamic acid, phenylalanine, alanine) addition to the linoleic acid emulsion was conducted. Amino acid solutions in concentrations of $10^{-2}$, $10^{-3}$ and $10^{-4}M$ were mixed with equal volume of linoleic acid emulsions. The prepared samples were incubated at $60{\pm}1^{\circ}C$ and the extent of diene conjugation and TBA values were measured by using the UV visible spectrophotometer. The results were as follows: 1) From the extent of diene conjugation, we found that the addition of phenylalanine and alanine prolonged the induction period and the addition of glutamic acid shortened. There was an optimum concentration for each amino acid to act as an antioxidant during the induction period. The optimum concentration of alanine was $10^{-3}M$ and that of phenylalanine was $10^{-2}M$. 2) The results of TBA values showed that three amino acids possesed antioxidant activity after the induction period. There was also an optimum concentration to act as antioxidant after the induction period. The optimum concentrations of glutamic acid, phenylalanine, and alanine were $10^{-2}$, $10^{-3}$, and $10^{-3}M$, respectively.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.6 no.1
• /
• pp.17-20
• /
• 1977

Contents of free amino acids and organic acids in the leaves of Ailanthus altissima were surveyed through the course of this study. The results were as follows; 1. Lysine, histidine, arginine, tryptophan, aspartic acid, glutamic acid, threonine, serine, proline, glycine, alanine, valine, leucine, isoleucine, methionine, tyrosine and phenylalanine were presented in the leaves of A. altissima, and glutamic acid showed the highest amount and was more than about 48% of total free amino acids. 2. Fumaric acid was the major organic acid in the leaves of A. altissima, and also formic acid, acetic acid, maleic acid, succinic acid, oxalic acid, citric acid, tartaric acid and sorbic acid were determined, and two unknown were found.

• Animal Bioscience
• /
• v.34 no.12
• /
• pp.1963-1973
• /
• 2021

Objective: The present study aimed to evaluate the influence of including L-glutamine along with glutamic acid as a supplement in weaned piglets' diets with and without whey powder. Methods: Two assays were carried out. A total of 40 piglets ([Landrace×Large White]×Pietrain) weaned at 24 days of age with an initial body weight of 6.6±0.6 kg were used in the first assay, and the following parameters were evaluated: growth performance, the incidence of diarrhea, morphometry, intestinal integrity, and hepatic glycogen index. The animals were then blocked into four groups according to different diets: diet all-grain feeding (G); diet all-grain feeding with whey powder (GW); and with vs without 1% supplementation of the commercial product containing L-glutamine and glutamic acid (A or NA). Whey powder was added according to the stage of life, corresponding to 17%, 10%, and 5%, respectively, in order to meet the need for lactose. The animals were evaluated at 24 to 42 days and at 24 to 55 days of age. The nutrient digestibility for the second assay was carried out by using 24 animals with an average weight of 11.49±1.6 kg, and the same diets were tested. Results: The supplementation of L-glutamine + glutamic acid or the addition of whey powder in diets for weaned piglets provided (p<0.05) greater feed intake, greater weight gain and improved feed conversion in the initial period (24 to 42 days age). However, in the whole period (24 to 55 days age) only amino acid supplementation affected (p<0.05) growth performance. There was a positive interaction (p<0.05) between the type of diet and L-glutamine + glutamic acid supplementation on villus height, crypt depth and the villus:crypt ratio in the duodenum. In addition, L-glutamine + glutamic acid supplementation reduced (p<0.05) the crypt depth and improved the villus:crypt ratio in the jejunum. The inclusion of whey powder affected (p<0.05) positively the digestibility coefficients analyzed except mineral matter digestibility coeficients. The supplementation of 1% the commercial product composed of L-glutamine and glutamic acid improved (p<0.05) only the digestibility coefficient of crude protein. Conclusion: These results indicate that supplementation of 1% commercial product containing L-glutamine + glutamic acid in diets for piglets from 24 to 55 days of age, dispenses with the use of whey powder when evaluating growth performance. Amino acid supplementation alone or associated with whey powder affects (p<0.05) positively the indicators of the intestinal integrity.

• The Korean Journal of Malacology
• /
• v.19 no.2
• /
• pp.95-106
• /
• 2003

The compositions of amino acid in 6 monocultured benthic diatoms used in aquaculture of Haliotis discus hannai were analyzed, and effects of 15 artificial synthetic amino acids on the settlement and metamorphosis of H. discus hannai larvae. Results showed that the content of L-aspartic acid was highest in all diatoms, and that of L-glutamic acid was second high. In experiment using settlement slat without benthic diatom attached, the highest settlement rate (33.3 ${\pm}$ 8.8%) was obtained with L-glutamic acid, and a higher value (16.7 ${\pm}$ 3.3%) was found with L-aspartic acid at 24 h after experimental commencement, compared to that of control (8.6 ${\pm}$ 5.1%). 80 h later the metamorphosis rates of L-glutamic acid (86.7 ${\pm}$ 10.7%) and L-aspartic acid (80.0 ${\pm}$ 3.3%) groups were higher than control group(0) and other amino acids significantly. The response rate of L-glutamic acid was the highest (62.0%), and those of L-aspartic acid (30.0%) and L-threonine (25.3%) groups were also significantly higher than control group. In the experiment using settlement slat with benthic diatom attached, the best effect of various amino acids on induction of larval settlement was obtained with L-glutamic (82.0 ${\pm}$ 6.9%) and L-aspartic acid (78.7 ${\pm}$ 5.1%) at 24 h after experimental commencement. The settlement rates of L-histidine, L-leucine, L-lysine, L-methionine, L-phenylalanine, and L-tyrosine groups were significantly lower than control group. The same differences in the metamorphosis rate at 56 h after experimental commencement and in the response rate were found. It should be noted that after 80 h the metamorphosis rates of L-histidine (74.0 ${\pm}$ 12.0%) and L-lysine (87.0 ${\pm}$ 8.8%) declined rapidly compared to those of 56 h (8.0 ${\pm}$ 12.0%; 7.7 ${\pm}$ 12.0%).

• Journal of Nutrition and Health
• /
• v.13 no.2
• /
• pp.92-103
• /
• 1980

Components of neutral lipids and amino acids of Hirneola auricula-Judae and Gyrophora esculenta grown in Korea were compared by using a Thinchrography (latroscan TH-10) and an amino acid auto analyzer(Technicon PNC-1 type), respectively. Cholesterol ester and tripalmitin were the major components among the triglycerides in both of the samples. From the total amino acids which are closely related with the nutritional valuation, aspartic acid was in the richest amount and then came with glutamic acid, serine, alanine and valine in Hirneola auricula-Judae and Gyrophora esculents contained large quantity of glutamic acid.

• Applied Biological Chemistry
• /
• v.25 no.3
• /
• pp.173-176
• /
• 1982

The amino acids in the mucilage and its hydrolyzed products from Ulmus coreana, Nakai root were detected by thin layer chromatography. The mucilage contained 10 kinds of amino acids; alanine, aspartic acid, glutamine, glutamic acid, hydroxyproline, isoleucine, leucine, proline, phenylalanine and tyrosine. In the hydrolyzed mucilage 14 kinds of amino acids were detected; alanine, aspargine, arpartic acid, glutamine, glutamic acid, hydroxyproline, isoleucine, leucine, methionine, proline, phenylalanine, serine, tyrosine and valine.

• Korean Journal of Animal Reproduction
• /
• v.26 no.4
• /
• pp.369-375
• /
• 2002

A sperm factor(s) for oocyte activation during fertilization has not been clearly identified. In this study to elucidate an oocyte activation factor(s), mouse sperm were sonicated and ultra-filtered with a 30 kilo-daltons (KD) cutoff membrane and the ultra-filtrate was then sequentially fractionated over Suporose 12 column and Superdex column, The recovered fractions were micro-injected into Mⅱmouse oocytes and second polar body formation (PBF) was examined. Suporose fraction RV2.10 prepared from sperm extract significantly increased PBF. Of Superdex fractions re-separated from Suporose fraction RV2.10, fraction RV2.12 also had the strongest PBF activity. By analyzing with micro-reverse phase column (URPC), the Superdex fraction RV2.12 appeared to be glutamic acid. In microinjection test, glutamic acid significantly increased PBF. This study suggests that glutamic acid should be a type of sperm factor for second polar body formation related to oocyte activation.