• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.65-68
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• 2000

To obtain quality germinated brown rices containing high levels of ${\gamma}-amonobutyric\;acid$(GABA), chitosan was appliec during the germination of brown rices. The GABA contents of germinated brown rices (1,035 umole/g fresh weight) with 100 ppm chitosan solution for 72 hr were higher than those of ungerminated brown rices (136 nmole/g fresh weight) and brown rices germinated with water (771 nmole/g fresh weight) or with lactic acid (728 nmole/g fresh weight). In addition to the enhancement of GABA, germination in the chitosan solution increased alanine and decreased glutamic acid, aspartic acid and serine in the brown rices. The activity of glutamate decarboxylase was also enhanced by the treatment of chitosan. Furthermore, the germination with chitosan reduced fungi contamination markedly compared with water germination or lactic acid germination. These results suggest that quality germinated brown rices containing high levels of GABA can be obtained by chitosan application.

• Journal of Animal Science and Technology
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• v.60 no.7
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• pp.19.1-19.10
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• 2018

Background: A mold strain thought to be suitable for dry-aging process was isolated. The information about the scientific aspects of molds related to dry-aging beef is scarce. We, therefore, conducted aging trials to determine the characteristics of the isolated mold strain associated with dry-aging process. Specifically, during the dry-aging of beef with the mold strain, the changes in the free amino acid content, hardness, productive loss, drip and cooking loss were analyzed. These characteristics were compared with those obtained while dry-aging in the absence of a mold. Results: The isolated mold strain was identified as Mucor flavus. The free amino acid content in the mold-aging beef decreased or remained constant during the aging process. However, that in the trimming sections of the beef dramatically increased in the presence of mold. In addition, hardness of mold-aging beef gradually decreased during the aging process and finally decreased significantly. Conclusion: Amino acids such as GABA (gamma-aminobutyric acid), proline, and aspartic acid were produced by our mold strain, M. flavus during its growth on beef meat, and the mold conferred savory odors to the dry-aged beef.

• Korean Journal of Food Science and Technology
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• v.48 no.3
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• pp.214-222
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• 2016

This study was performed to increase the production of ${\gamma}$-aminobutyric acid (GABA) by lactic acid bacteria (Lactobacillus brevis CFM11) and manufacture an optimum medium using the sap from Darae (Actinidia arguta). The concentration of GABA in the fermented sap was determined using GABase enzymatic assay. The isolated L. brevis CFM11 produced $605.67{\mu}g/mL$ GABA after incubation for 24 hours at $37^{\circ}C$ in broth. The sap was fermented by L. brevis CFM11 under optimum conditions of $32^{\circ}C$ for 48 hours with 40% rice bran extract, 1.0% sucrose, 3.0% soytone, 0.2% magnesium sulfate, and 0.2% MSG. The fermented sap produced a concentration of $1366.13{\mu}g/mL$ GABA. These results demonstrate that fermenting Darae sap using L. brevis CFM11 can produce a fermented sap beverage with increased GABA content.

• Biomolecules & Therapeutics
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• v.22 no.4
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• pp.314-320
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• 2014

This study was investigated to know whether pachymic acid (PA), one of the predominant triterpenoids in Poria cocos (Hoelen) has the sedative-hypnotic effects, and underlying mechanisms are mediated via ${\gamma}$-aminobutyric acid (GABA)-ergic systems. Oral administration of PA markedly suppressed locomotion activity in mice. This compound also prolonged sleeping time, and reduced sleep latency showing synergic effects with muscimol (0.2 mg/kg) in shortening sleep onset and enhancing sleep time induced by pentobarbital, both at the hypnotic (40 mg/kg) and sub-hypnotic (28 mg/kg) doses. Additionally, PA elevated intracellular chloride levels in hypothalamic primary cultured neuronal cells of rats. Moreover, Western blotting quantitative results showed that PA increased the amount of protein level expression of $GAD_{65/67}$ over a broader range of doses. PA increased ${\alpha}$- and ${\beta}$-subunits protein levels, but decreased ${\gamma}$-subunit protein levels in $GABA_A$ receptors. The present experiment provides evidence for the hypnotic effects as PA enhanced pentobarbital-induced sleeping behaviors via $GABA_A$-ergic mechanisms in rodents. Taken together, it is proposed that PA may be useful for the treatment of sleep disturbed subjects with insomnia.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.8
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• pp.985-991
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• 2008

This study was to investigated the changes of physiologically active components in germinated brown rice treated with chitosan (CGBR) and its anti-obesity effect in rat fed a high fat diet. Contents of physiologically active compounds such as total phenolic compounds, total dietary fiber, $\gamma$-aminobutyric acid (GABA), and total phytic acid in CGBR were significantly higher than those of traditional germinated brown rice (GBR). Lipase inhibitory activity of CGBR was higher than those of GBR and brown rice (BR). High fat diets containing CGBR, GBR, and BR were administered to three groups of male Sprague-Dawley rats for four weeks. All groups showed no significant difference in body weight, total abdominal fat, and plasma lipid levels. However, CGBR group appeared to have lower body weight gain and total abdominal fat level than other groups fed high fat diets containing GBR and BR. Total cholesterol and LDL-cholesterol contents in plasma of CGBR group were also lower than those of other groups. Thus, new germination method of brown rice using chitosan is a useful process, which utilizes plant defense responses to elevate the production of secondary metabolites and anti-obesity effect.

• Preventive Nutrition and Food Science
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• v.9 no.4
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• pp.324-329
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• 2004

In order to investigate the molecular mechanism of $\gamma$-aminobutyric acid (GABA) production in lactic acid bacteria, we cloned a glutamate decarboxylase (GAD) gene from Lactobacillus plantarum using polymerase chain reaction (PCR). One PCR product DNA was obtained and inserted into a TA cloning vector with a T7 promoter. The recombinant plasmid was used to transform E. coli. The insertion of the product was con­firmed by EcoRI digestion of the plasmid purified from the transformed E. coli. Nucleotide sequence analysis showed that the insert is a full-length Lactobacillus plantarum GAD and that the sequence is $100\%$ and $72\%$ identical to the regions of Lactobacillus plantarum GAD and Lactococcus lactis GAD sequences deposited in GenBank, accession nos: NP786643 and NP267446, respectively. The amino acid sequence deduced from the cloned Lactobacillus plantarum GAD gene showed $100\%$ and $68\%$ identities to the GAD sequences deduced from the genes of the NP786643 and NP267446, respectively. To express the GAD protein in E. coli, an expression vector with the GAD gene (pkk/GAD) was constructed and used to transform the UT481 E. coli strain and the expression was confirmed by analyzing the enzyme activity. The Lactobacillus plantarum GAD gene obtained may facilitate the study of the molecular mechanisms regulating GABA metabolism in lactic acid bacteria.

• Journal of Ginseng Research
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• v.36 no.1
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• pp.55-60
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• 2012

In a previous report, we demonstrated that ginsenoside Rc, one of major ginsenosides from Panax ginseng, enhances ${\gamma}$-aminobutyric acid (GABA) $receptor_A$ ($GABA_A$)-mediated ion channel currents. However, little is known about the effects of ginsenoside metabolites on $GABA_A$ receptor channel activity. The present study investigated the effects of ginsenoside metabolites on human recombinant $GABA_A$ receptor (${\alpha}_1{\beta}_1{\gamma}_{2s}$) channel activity expressed in Xenopus oocytes using a two-electrode voltage clamp technique. M4, a metabolite of protopanaxatriol ginsenosides, more potently inhibited the GABA-induced inward peak current ($I_{GABA}$) than protopanaxadiol (PPD), a metabolite of PPD ginsenosides. The effect of M4 and PPD on $I_{GABA}$ was both concentration-dependent and reversible. The half-inhibitory concentration ($IC_{50}$) values of M4 and PPD were 17.1${\pm}$2.2 and 23.1${\pm}$8.6 ${\mu}M$, respectively. The inhibition of $I_{GABA}$ by M4 and PPD was voltage-independent and non-competitive. This study implies that the regulation of $GABA_A$ receptor channel activity by ginsenoside metabolites differs from that of ginsenosides.

• BMB Reports
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• v.41 no.1
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• pp.23-28
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• 2008

The altered amino acid (AA) levels as neurotransmitter closely correlate to neurodegenerative conditions including Alzheimer's disease (AD). Target profiling analysis of nineteen AAs in brain cortex samples from three Tg2576 mice as AD model and three littermate mice as control model was achieved as their N(O,S)-ethoxycarbonyl/tert-butyldimethylsilyl derivatives by gas chromatography. Subsequently, star pattern recognition analysis was performed on the brain AA levels of AD mice after normalization to the corresponding control median values. As compared to control mice, $\gamma$-aminobutyric acid among ten AAs found in brain samples was significantly reduced (P < 0.01) while leucine was significantly elevated (P < 0.02) in AD mice. The normalized AA levels of the three AD mice were transformed into distorted star patterns which was different from the decagonal shape of control median. The present method allowed visual discrimination of the three AD mice from the controls based on the ten normalized AA levels.

• Preventive Nutrition and Food Science
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• v.18 no.2
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• pp.139-144
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• 2013

Laver, a red algae belonging to the genus Porphyra, is one of the most widely consumed edible seaweeds. The most popular commercial dried laver species, P. tenera and P. haitanensis, were collected from Korea and China, respectively, and evaluated for proximate composition, amino acids, minerals, trace heavy metals, and color. The moisture and ash contents of P. tenera and P. haitanensis ranged from 3.66~6.74% and 8.78~9.07%, respectively; crude lipid and protein contents were 1.96~2.25% and 32.16~36.88%, respectively. Dried lavers were found to be a good source of amino acids, such as asparagine, isoleucine, leucine, and taurine, and ${\gamma}$-aminobutyric acid. K, Ca, Mg, Na, P, I, Fe, and Se minerals were selected for analysis. A clear regional variation existed in the amino acid, mineral, and trace metal contents of lavers. Regular consumption of lavers may have heath benefits because they are relatively low in fat and high in protein, and contain functional amino acids and minerals.

• Clinical and Experimental Pediatrics
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• v.61 no.5
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• pp.150-155
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• 2018

Purpose: Infantile spasms, also known as West syndrome, is an age-specific epileptic seizure. Most patients with this condition also exhibit delayed development. This study aimed to determine the effect of long-term prenatal stress on susceptibility to infantile spasms. Methods: We subjected pregnant rats to acute or chronic immobilization stress. Resulting offspring received N-methyl-D-aspartic acid (15 mg/kg, intraperitoneally) on postnatal day 15, and their behaviors were observed 75 minutes after injection. The expression of KCC2 and GAD67 was also determined using immunohistochemistry. Results: Exposure to long-term prenatal stress increased the frequency of spasms and decreased the latency to onset of spasms compared with offspring exposed to short-term prenatal stress. Expression of KCC2 and GAD67 also decreased in the group exposed to long-term prenatal stress compared with the group exposed to short-term prenatal stress. Conclusion: Our study suggests that exposure to long-term prenatal stress results in increased susceptibility to seizures.