γ-aminobutyric acid (GABA) is a natural stress-reducing substance and is actively used as a human health supplement. However, minimal research has been conducted on its use in cattle. This study was conducted to evaluate the effects of GABA on the growth performance, complete blood count, blood metabolites, and carcass characteristics of fattening Hanwoo steers. Twenty-one fattening steers were randomly assigned to one of three treatments: control (basal diet: concentrate feed + rice straw), T1 (basal diet + GABA supplement at 0.8% of feed/head/day), and T2 (basal diet + GABA supplement at 1.6% of feed/head/day). Feed intake and conversion ratio did not differ among the treatments. However, the average daily gain during the early fattening period increased linearly to 0.80 kg, 0.86 kg, and 0.92 kg in the control, T1, and T2 groups (p<0.05). Plasma γ-glutamyl transferase (37.5, 58.2, 42.8 U/ℓ) and creatinine (1.32, 1.34, 1.49 ㎎/㎗) levels in the GABA supplement group were increased compared to those in the control group. The carcass weight (422.7, 427.1, 454.1 kg), rib eye area (86.67, 92.57, 91.14 cm2), and marbling score (3.67, 4.29, 4.14) were numerically higher in the GABA supplement group than in the control group. Thus, GABA supplementation positively affected the average daily gain and carcass characteristics of Hanwoo steers. However, the effect of the GABA supplement level of GABA was small, and further research using rumen-protected coating technology on GABA is necessary.

A γ-aminobutyric acid (GABA) producing microorganism was isolated from Sun-Tae Jeotgal, a Korean traditional fermented seafood. Two thousand presumptive lactic acid bacteria (LAB) isolates were screened for GABA production by thin layer chromatography. One isolate, T118, produced GABA profusely, and identified as Lactobacillus brevis. Growth of Lb. brevis T118 was examined during 120 h cultivation in MRS broth under different conditions. Lb. brevis T118 grew well at 30-37℃, initial pH of 4-7, and up to 5% NaCl (w/v). A gene, gadB, encoding glutamate decarboxylase (GAD) was cloned by PCR. gadC encoding a glutamate/GABA antiporter was cloned and gadC located immediately upstream of gadB, indicating gadCB operon structure. The operon structure was confirmed by reverse transcription (RT)-PCR. gadB was overexpressed in Escherichia coli BL21 (DE3) and recombinant GAD was purified. The size of recombinant GAD was 54.4 kDa by SDS-PAGE, which matched well with the calculated size from the nucleotide sequence.

본 연구는 γ-aminobutyric acid (GABA)가 여름철 산란계농장에서 산란계의 생산성에 미치는 영향을 구명하기 위하여 수행되었다. 동일한 사육규모(약 5만수/계사)의 계사에 수용된 산란계에게 44일간 GABA(100 ppm)를 급여하였고, 유사한 사육규모의 다른 한 동에 수용된 산란계는 비교집단(Ref)으로 이용되었다. 매일 최고 및 최저온도, 사료 및 물 섭취량, 산란수, 난중 및 폐사율은 계사단위로 측정 후 분석에 이용되었다. 실험기간동안 두 계사 간의 일중 최고 및 최저 온도는 유사하였다. 사료섭취량은 실험 개시 시점부터 GABA 처리 및 Ref 사이에 차이가 있었고 종료시까지 지속되었지만(p<0.05), 일일 평균산란량과 헨데이산란율은 유사하였다. 그 결과 사료요구율은 GABA 처리구에서 현저히 낮았다 (p<0.05). 물섭취량은 처음에 유사하였지만 시간과 더불어 GABA 처리구에서 증가하였고, 따라서 물섭취량 대 사료섭취량의 비는 5일 이후 GABA 처리구에서 현저히 증가하였다(p<0.05). 누적폐사율은 첫 15일 동안 GABA 와 Ref간에 유사하였지만 이후 GABA 처리구에서 현저히 낮았고, 그 차이는 시간의 경과와 함께 증가하였다. 난중별 비율에서도 차이가 있었으며, GABA 처리구에서 대란의 비율이 높았고 특란의 비율은 낮았다(p<0.05). 파란율은 Ref에 비해 GABA 처리구에서 높았지만, 이러한 경향은 GABA 급여 개시 전에도 발견되어 GABA 처리와 무관한 것으로 판단되었다. 따라서 본 연구결과는 GABA가 여름철 산란계의 폐사율 저감에 기여할 수 있음을 시사한다.

This study aimed to investigate the changes in the γ-aminobutyric acid (GABA) content of bitter melon (Momordica charantia L.) cultivated from different regions, with different harvest times and at various maturation stages. Methods for observing the changes in GABA content were validated by determining the specificity, linearity, limit of detection (LOD), limit of quantification (LOQ), and precision and accuracy using the HPLC-FLD system. Results showed high linearity in the calibration curve with a coefficient of correlation (R2) of 0.9999. The LOD and LOQ values for GABA were 0.29 and 0.87 μg/mL, respectively. The relative standard deviations for intra- and inter-day precision of GABA were less than 5%. The recovery rate of GABA was in the range of 98.77% to 100.50%. The average content of GABA was 0.93 mg/g and Cheongju showed highest GABA content of 1.88 mg/g. As the time of harvest increased from May to September, the GABA content decreased from 1.56 to 0.86 mg/g. Also, maturation of the bitter melon fruit was associated with a decreased in GABA content.

This study was carried out to establish a cultivation technique for increasing the γ-aminobutyric acid (GABA) content in the fruit body of mushrooms by adding processed by-products. For the oyster mushroom ‘Heucktari’, addition of green tea powder, sea tangle powder, and green tea dregs resulted in very poor primordia formation, fruit body growth, and increased GABA. However, addition of 10% schizandra berry dregs and 1% rice bran to the basal substrate induced 100% and 10% increases, in GABA content in the fruit bodies compared to the control treatment without by-product, respectively. In addition, fruit body growth and primordia formation were greatly increased by these treatments. Therefore, GABA content was increased when the substrate was prepared by mixing an appropriate amount of schizandra berry dregs and rice bran.

Sparassis latifolia (formerly S. crispa) is used in food and nutraceuticals or dietary supplements, as rich in flavor compounds and β-glucan. Some previous studies have reported the effects of mushroom on brain function, including its neuroprotective effect. Thus, for this mushroom to be used as an effective nutraceutical for brain function, it would be desirable for it to contain other compounds such as γ-aminobutyric acid (GABA) in addition to β-glucan. In this study, the enhancement of growth and GABA production in the mycelium of medicinal and edible mushroom S. latifolia was investigated. Amino acids were added externally as the main source of nutrition, and the effects of amino acids were investigated using liquid medium, specifically amino acid-free potato dextrose broth (PDB). The amino acids added were L-glutamic acid (named PDBG medium) and L-ornithine (named PDBO medium). The growth of mycelia was determined to be 0.9 ± 0.00 g/L, 2.2 ± 0.16 g/L, and 1.93 ± 0.34 g/L PDBG respectively. The GABA content was 21.3 ± 0.9 mg/100 g in PDB medium, and it in PDBG 1.4% medium, at 115.4 ± 30.2 mg/100 g. However, the PDBO medium was not effective in increasing the GABA content of mycelia. Amino acids had little effect on the β-glucan content of mycelia. The β-glucan content was 39.7 ± 1.4 mg/100 mg, 34.4 ± 0.2 mg/100 mg, and 35.2 ± 9.2 mg/100 mg in PDB, PDBG 1.8% and PDBO 1.4% media, respectively. Addition of glutamic acid and ornithine positively affected the growth of S. latifolia mycelia, and glutamic acid positively affected GABA production; no degradation of GABA was observed with addition of glutamic acid.

팽이버섯 내에 존재하는 GAD 효소를 발효를 통해 활 성화 시켜 MSG를 GABA로의 전환율을 높이고자 하였다. 효과적인 고농도 GABA를 생산하기 위해 나노분말 팽이 버섯에다가 수경재배한 인삼을 첨가하여 야쿠르트발효기 에서 발효한 결과 GABA 전환율은 팽이나노인삼분말 발 효군(88%) > 팽이분말 발효군(52%) > 팽이나노분말 발 효군(44%) 순으로 나타났다. 이러한 결과는 MSG를 기질 로 첨가하는 식품에서 활용할 가치가 있으리라 사료된다.

γ-Aminobutyric acid (GABA)-containing salt was prepared by crystallization of a mixture of salt water from deep sea and fermentation broth by lactic acid bacteria that contained GABA converted from glutamic acid. Salt from deep sea water has a lower sodium content but higher calcium, potassium and magnesium contents than commercial salt. Instead of monosodium glutamate (MSG), glutamic acid was used for solving the residual MSG problem. Fermentation by a lactic acid bacterium converted 90% of added glutamic acid (5%, w/v) to GABA, and continuous production of colorless fermentation broth containing more than 3% (w/v) GABA was achieved by using an activated carbon. Mixtures of salt water and fermentation broths with various GABA concentrations were co-crystallized and the GABA content was analyzed. This analysis showed that more than 90% of GABA from broth was adsorbed to salt. The appearance and surface of this prepared GABA-containing salt were examined with an image analyzer and scanning electron microscope. No difference was found with commercial sun-dried salt and no separated particles were detected, which indicates that the co-crystallization process used is suitable for the production of GABAcontaining salt.

γ-Aminobutyric acid (GABA) is present in many vegetables and fruits, but not in dairy products. GABA is known to be beneficial for preventing neurological disorders and hypertension. The objective of this study was to measure the physicochemical changes, number of lactic acid bacteria, and GABA content in fermented goat milk containing rice (1%). The levels of pH and titratable acidity (TA) in each test samples were found to be pH 4.4∼4.5 and 0.74∼0.8%, respectively. The number of viable lactic acid bacteria between test samples ranged from 8.63 to 8.95 Log CFU/ml. Therefore, pH, TA, and number of viable cells in each test sample had no difference. Furthermore, the Lactobacillus delbrueckii subsp. bulgaricus SP5 (Lb. bulgaricus SP5) showed the highest GABA production in goat milk containing rice. Its maximum GABA yield was 3.4 mg/100 mL. The results suggest that GABA contents of fermented goat milk containing rice can be enriched using Lb. bulgaricus SP5.

The Lactobacillus brevis 340G strain isolated from traditional Korean fermented food (kimchi) produced 15.50mMof γ-aminobutyric acid (GABA) after 48 h of cultivation in MRS media containing 1% L-monosodium glutamate(MSG). The culture conditions of Lb. brevis 340G were optimized for GABA production. Lb. brevis 340G was cul-tivated at 30oC in optimized MRS media containing 3% sucrose and 2% yeast extract with 3% MSG, resulting inmaximum GABA production (68.77mM) after 54 h of cultivation. Skim milk fermented with Lb. brevis 340G pro-duced 4.64mM of GABA in the presence of 1% MSG. These results suggest that Lb. brevis 340G could be usedas a starter for functional fermented foods and skim milk fermented with Lb. brevis 340G could be further devel-oped to become functional dairy food fortified with GABA.

Soymilk has been substituted for milk for people who are suffering from lactoseintolerance. In this study γ-aminobutyric acid (GABA) producing lactic acid bacterium, Lactobacillus plantarum LP2, was applied to ferment soymilk for improving its functionality. GABA production was proved in MRS broth supplemented 3% monosodium glutamate (MSG) and soymilk including 10% (w/v) soymilk powder and 5%(w/v) fructooligosaccharide where L. plantarum LP2 was applied. In addition to the soymilk, isolated soy protein (ISP), which was enzyme-treated, was added to it for improving the content of free amino acids including glutamic acid. L. plantarum LP2 was well grown and produced GABA in the soymilk medium.

In this study, soy-powder yogurt (SPY) with enhanced levels of γ-aminobutyric acid (GABA) and isoflavone aglycone was produced from sprouting high-protein soybeans (HPSs). The fermented steam-HPS sprouts (0 to 4 cm) were fermented (72 h) with Lactobacillus brevis, and the total free amino acids (FAAs) of the formed mixtures were determined to be 79.53, 489.93, 877.55, 780.53, and 979.97 mg/100 mL in the fermented HPS (FHPS), and the fermented steam-HPS with 0 cm (FSHPS-0), 1 cm (FSHPS-1), 2 cm (FSHPS-2), and 4 cm sprouting lengths (FSHPS-4), respectively. The levels of glutamic acid (GA) and GABA were observed to be the highest, 100.31 and 101.60 mg/100 mL, respectively, in the unfermented HPS (UFSHPS-1, 1 cm) and FSHPS-1 sprouts, respectively. Moreover, the total contents of the isoflavone glycoside form decreased proportionally to the increasing total levels of isoflavone aglycones after fermentation in FSHPS-0, FSHPS-1, FSHPS-2, and FSHPS-4. The levels of isoflavone aglycones were detected as 350.34, 289.15, 361.61, 445.05, and 491.25 μg/g in FHPS, FSHPS-0, FSHPS-1, FSHPS-2, and FSHPS-4, respectively. While FSHPS-1 exhibited the highest DPPH (63.28%) and ABTS (73.28%) radical scavenging activities, FSHPS-4 contained the highest isoflavone aglycone ratio (81.63%). All in all, the FSHPS-1 mixture prepared in this study exhibited high GABA content and functional prosperity, thereby making it suitable for potential applications in the soy-dairy industry.

팽이버섯 분말을 이용하여 기능성물질인 GABA 및 probiotics를 강화시킨 천연 발효조미료를 개발하기 위해서 L. plantarum EJ2014에 의한 젖산발효 최적화 연구를 수행하였다. 팽이버섯 분말에 영양성분 0.5% YE, 1% glucose, GABA 전구물질인 5% MSG를 첨가한 후 30℃에서 5일간 젖산발효를 진행한 결과 발효 2일 동안 pH는 6.1에서 4.4로 감소하다가 발효 5일에 6.2로 다시 증가하는 경향을 보였으며 산도는 발효 2일 동안 0.5%에서 1.3%로 증가한 후 발효 5일에 다시 0.4%로 감소하는 경향을 보였다. 생균수는 초기 젖산균 스타터 2.4×107 CFU/mL에서 발효 1일째 2.2×109 CFU/mL로 증가한 후 5일 동안 계속 유지되었다. 전구물질인 MSG는 발효 4일에 대부분이 이용되면서 약 2.31% 농도의 GABA로 전환되었으며 DPPH radical 소거 활성은 IC50 값이 1.24 mg/mL로, ABTS radical 소거 활성에서 IC50 값은 1.53 mg/mL로 나타나면서, 발효물의 항산화 효과가 증진되는 것으로 나타났다. 또한 팽이버섯 발효물 30 g에 볶은 밀기울 1 g을 첨가하여 열풍 건조한 천연 발효조미료의 GABA 함량은 17%로 고농도의 GABA를 함유하여 probiotic 기능성이 강화되며 기호성을 갖는 발효조미료 및 건강소재의 제조가 가능하였다.

GABA는 glutamic acid decarboxylase에 의해서 L-glutamic acid가 탈탄산화되어 생합성된 비단백질 아미노산이다. GABA는 식물에서 스트레스에 대항한 대응반응으로 생성된다. 사 람의 중추신경계에서는 주요 억제성 신경전달물질 중 하나로 항고혈압, 항당뇨 효능이 있 다고 알려져 있다. 본 연구에서 우리는 보리 잎과 옥수수 수염을 유산균과 함께 발효함으 로써 GABA 생성을 증진시키고자 하였다. 보리 잎과 옥수수 수염을 다양한 무게 비율로 조 합하여 혼합하였고, 30℃에서 48시간 동안 배양기 안에서 L. plantarium과 함께 발효시켰다. 발효된 혼합물을 열수 추출한 후, thin layer chromatography와 GABase assay를 이용하여 GABA의 생산을 분석하였다. 우리는 9:1 혼합발효추출물이 다른 비율의 추출물 보다 GABA 함량이 높은 것을 확인하였는데 이것은 혼합과 발효기술이 보리 잎과 옥수수 수염 내 GABA 양 증진에 효과가 있음을 의미한다. 또한 몇 가지 생리활성을 분석한 결과 혼합 발효추출물의 항산화 효능이 비발효 추출물에 비하여 증진되었고 세포독성은 나타나지 않 음을 확인하였다. 이러한 결과는 보리 잎과 옥수수 수염의 조합과 이것을 유산균과 함께 발효시키는 방법이 고함량의 GABA와 증진된 생리 활성을 지닌 기능성 식품으로서의 개발 가능성이 있음을 의미한다.

The GA application on grapevines induces parthenocarpy, fruit set without fertilization, and the inhibition of pollen tube growth. But the molecular mechanism underlying this inhibition is not understood. Similar defective pollen tube growth within the transmitting tract has been reported in the mutant of GABA transaminase (GABA-T), referred to as pollen-pistil-interaction2 (pop2) in Arabidopsis. In spite of the similarity of pollen tube growth inhibition observed in GA-applied grapevines with that of pop2, only the effects of GABA on stress responses in grapevines have been reported. In present study, transcriptional changes of Vitis GABA metabolic genes, together with changes in GABA levels with or without GA application were analyzed to define how GA application restrained the pollen tube growth in grapevines. A GA solution (Dongbu, Seoul, Korea) at 100 ppm was onto inflorescence clusters 14 days before full bloom (DBF) and clusters were harvested at 0, 1, 2, 4, 7, 9, 12, 14, 16, and 19 days after GA application. Harvested inflorescence samples were immediately frozen in LN2 and extracted RNA and amino acid. The GABA contents were analyzed using high-performance liquid chromatography (Agilent 1100 HPLC, Agilent Technologies, Inc., Santa Clara, USA) equipped with a C18 column (4.6 mm×150 mm, 3.5 μm/VDS optilab, Berlin, Germany), according to the manufacturer’s instructions. Without GA application, the simultaneous high expressions of VvGAD1, VvGAD4 and VvGABA-T2 during 10 to 5 days before full bloom (DBF) showing the activation of GABA metabolism. But the contents of GABA were low before 2 DBF, and it peaked only at near full bloom when expression levels of VvGABA-T2 remained low. After GA application, the contents of GABA were constant during 10 to 5 DBF, although transcription levels of both VvGAD1 and VvGABA-T2 rapidly declined less than 30% of the levels observed without GA application. However, the GABA levels increased more than 2-fold only at near full bloom, compared to those without GA application, and at that time, expression levels of VvGAD1 up-regulated more than 3-fold and those of VvGABA-T2 kept low. But other amino acid contents did not show significant changes. In case of VvSSAHDs, their transcriptional changes with or without GA application were not correlated with GABA levels. These results indicates that GABA levels before pollination is tightly regulated, but GA application alters the GABA-shunt to accumulate excess GABA more than needed for proper pollen tube growth at full bloom. Gibberellin application alters the GABA-shunt to accumulate excess GABA resulting in inhibition pollen tube growth in grapevines.

거대쌀눈의 특성과 검정쌀 그리고 찹쌀의 특성을 보유한 눈큰흑찰의 침종과 발아 그리고 기질로 글루탐산을 처리하 였을 경우의 가바를 포함한 주요 성분의 분석 결과는 다음 과 같다. 1. 싹 발아 길이를 기준으로 눈큰흑찰의 가바 함량은 싹 길이가 5~10 mm인 stage-3에 93.9 mg/100 g으로 최 고를 보였고, 대량 제조 조건에서는 최고 126.9 mg의 가바를 함유하고 있음을 확인하였다. 2. 침종에 의한 성분 분석에서는 72시간 침종에서 폴리 페놀, 플라보노이드, 아미노산 그리고 가바 함량이 가 장 많이 축적됨을 확인하였다. 3. 글루탐산 탈탄산효소의 작용에 의한 가바 함량 증가는 현미와 쌀겨 모두에서 급격한 증가가 관찰되었고, 눈 큰흑찰 현미와 쌀겨의 경우 가바 함량이 각각 354.6 mg/100 g과 726.4 mg으로 현미와 쌀겨에 비해 각각 14배와 3배 함량이 증가하였다. 따라서 본 연구에서 눈큰흑찰의 발아와 침종에 따른 품질 특성을 분석한 결과, 뇌의 대사전달 물질의 조정 작용과 고 혈압 그리고 스트레스 조정 기능이 있는 가바의 함량이 침 종과 발아에 의해 일반 쌀에 비해 급격히 증가함을 확인하 였다. 특히나 글루탐산탈탄산 효소의 작용에 의한 눈큰흑찰 의 현미와 쌀겨의 가바 생성은 현재까지 보고된 그 어떤 쌀 품종에서 분석된 가바 함량보다도 가장 우수함을 확인할 수 있어 향후 기능성 발아현미 가공을 위한 원료로 활용이 가 능하며, 침종 조건은 가바 함량이 증진된 밥의 제조에 활용 이 가능하고, 일본에서 시판되는 가바 건강식품의 용량과 맞먹는 함량을 지닌 눈큰흑찰을 이용한 가바쌀 생산과 가바 의 효능에 의한 혈압강하, 체중조절, 알코올 관련 질환 등에 효능이 있는 건강기능성 식품 원료로 활용이 가능할 것으로 사료된다.

~gamma -Aminobutyric acid (GABA) is a non-protein amino acid that is widely distributed in plant and animal kingdom. GABA is found in tissues of the central nervous system (CNS) in animals. GABA functions as a the major inhibitory neurotransmitter in the CNS by acting through the GABA receptors. Clinical studies have revealed the relationship between an increased intake of GABA or analogues with several health benefits, including lowering of blood pressure in mildly hypertensive animals and humans. Furthermore, GABA would also has an inhibitory effect on cancer cell proliferation, stimulates cancer cell apoptosis and plays a role in alcohol-associated diseases and schizophrenia. In plants, interest in the GABA emerged mainly from experimental observations that GABA is largely and rapidly produced in large amounts in response to biotic and abiotic stresses. In this study, we speculated the properties and metabolism of GABA in plant and functions in relation to the responses to environmental stresses.

10℃ N2 gas 3시간 처리시 무처리에 비해 총질소, 총아미노산, 비타민 C 함량이 약간 높았고, 탄닌과 엽록소 함량은 낮은 경향이었다. 기능성 성분인 GABA 함량은 무처리 (35mg/100g)에 비해 51~205mg/100g으로 1.5~6배 높았다. 제다 품질은 무처리에 비해 3시간 gas 처리시 차이가 없었다. 20℃ N2 gas 3시간 처리가 무처리에 비해 품질관련 성분 중 총질소, 총아미노산(데아닌), 카페인 함량은 많았고, 탄닌과 비타민 C 함량은 약간 낮았다. GABA함량은 무처리 (35mg/100g)에 비해 gas처리가 85~225mg/100g으로 2.5~7배 높았다. 제다 품질은 무처리 80.4점에 비해 gas 처리 76.3~78.1점으로 약간 저하되었다. 30℃ N2 3시간 처리시 무처리와 기호성 관련성분이 거의 차이가 없었고 1, 5시간 처리는 무처리에 비해 품질이 약간 떨어지는 경향이었다. GABA 함량은 무처리 (30mg/100g)에 비해 gas처리가 115~217mg/100g으로 3~7배 증가하였다 제다품질도 무처리 80.4점에 비해 gas 처리가 74.3~77.2점으로 열악하였다. 따라서, 10℃에서는 5시간 gas처리, 20, 30℃에서는 3시간 gas 처리 후 제다를 하는 것이 기호성 및 기능성이 우수한 녹차(GABA차)를 제조할 수 있다고 생각된다.