본 연구의 목적은 효소 가수분해 및 유산균 혼합발효기술을 이용하여 GABA 함량이 강화된 발효 다시마 추출물을 생산함에 있다. TLC 분석방법을 통해 GABA 생성능력이 우수한 균주 L. plantarum KCTC 21004, L. acidophilus KCTC 3164, L. sakei subsp. sakei KCTC 3598를 선정하였 다. 선정된 균주를 이용한 유산균 발효의 특성은 배양 시간이 증가 할수록 적정 산도는 증가하였고 pH 는 감소하는 경향을 나타내었다. GABA 생성능력이 우수한 3종의 균주 중 L. plantarum KCTC 21004 이 GABA 함량이 136.4 mg/100g으로 우수하였다. 이러한 연구 결과는 유산균을 이용한 GABA 생산과 정에 있어서 기초적인 자료로 제공될 것으로 판단된다.

GABA는 식물, 동물 및 미생물 등 자연계에 다양하게 존재하고 있으며, 항고혈압, 이뇨, 진정, 수면유도 및 항스트레스 등 다양한 효과가 있는 것으로 알려져 있어서 식품, 의약품 소재로 활용되고 있다. 본 연구에서는 김치로부터 분리한 GABA 형성 유산균을 옥수수 수염 추출물에 적용하여 발효 특성과 발효물의 항산화 효과에 대해 분석하였다. 신규 L. plantarum LAB459의 분리와 동정은 생화학적 특성, 당자화성 및 16s rRNA 염기 서열 분석을 통해 확인되었다. 그리고 TLC와 HPLC 분석을 통해 분리된 L. plantarum LAB459가 GABA 생성능이 있는 것으로 나타났다. 그리고 탈지유가 포함된 옥수수 수염 열수 추출물에 대해 발효를 수행한 결과, 동결 건조된 발효물에 약 1 μg/mg 수준의 GABA가 형성된 것을 확인하였다. 또한 발효물에 대한 플라보노이드와 항산화 분석은 옥수수 수염 열수 추출물에 비해 더 높은 것으로 나타났다. 따라서 본 연구에서 분리된 L. plantarum LAB459는 다양한 식품 발효의 스타터 또는 식품 소재와 의약품 소재로 적용이 가능할 것으로 판단된다.

To develop Gamma-aminobutyric acid(GABA)-producing probiotics we isolated GABA-producing lactic acid bacteria from kimchi. 17 strains of GABA-producing lactic acid bacteria were isolated among 703 lactic acid bacteria originated from 21 kind of kimchi. Two strains, K991 and K998, were selected with highest GABA production ability. The results of 16S rRNA gene sequence analysis, K991 and K998 were identified as Lactococcus lactis, which showed 99.93% and 99.87% similarity, respectively. When the two strains were cultivated in MRS containing 5% MSG at 30°C, GABA began to be produced after 12 hours, reaching maximum production at 40 hours(13.20 mM and 13.35 mM, respectively). In contrast, GABA production was about three times lower when MSG was not added.

Gamma-aminobutyric acid (GABA) is a functional component with physiological activity that helps to protect the liver from blood pressure reduction and alcohol damage, and is known to be widely distributed in various vegetables and fruits. In this study, a fermented rice syrup with enhanced GABA content was developed. The improved syrup was prepared by adding monosodium glutamate (MSG) to saccharified rice and using a complex of three types of lactic acid bacteria (Lactobacillus brevis, Lactobacillus plantarum, Leuconostoc mesenteroides ) with excellent GABA production ability. The physicochemical changes of the fermented rice syrup were measured, and the final pH of the product was 4.7 with a total water-soluble solid content of 22.1 °Brix. Of the dissolved solids, glucose (39.6 mg/mL) and maltose (12.7 mg/mL) were the main components, and it was confirmed that all MSG was converted to GABA. From the experiment, it was established that the rice syrup obtained from secondary fermentation of saccharified rice is suitable as a beverage base. The fermented saccharified rice syrup was differentiated from conventional rice fermented products which typically use yeast and acetic acid bacteria in the production process. The enhanced fermented rice syrup produced in this study was made using lactic acid bacteria in the fermentation and saccharified rice.

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.

Sparassis latifolia is a fungus abundant in β-glucan and amino acids and is highly valued as a medicinal mushroom. Among amino acids, γ-aminobutyric acid (GABA) is a free amino acid and has biological effects, such as increase/decrease of hypertension, improvement of cerebral blood flow, and prevention of dementia. In this study, biological elicitors were used to increase bioactive substances as a biofortification method. Sodium alginate extracted from seaweed (Sargassum horneri, Sargassum fulvellum, Sargassum fusiforme) were used as the elicitor. The levels of β-glucan and GABA in the mycelium and fruiting body grown by adding the elicitor to the medium were investigated. Addition of sodium alginate positively affected GABA production and negatively affected the β-glucan production in these fungi. Sodium alginates extracted from S. fulvellum induced the highest increase in GABA in the mycelium and fruiting bodies. Moreover, we investigated the effects of the extracts from mycelium and fruiting bodies on dendrite development in primary cortical neurons. We found that the extract from the fruiting bodies of sodium alginate treated fungi with increased levels of GABA inhibited the dendrite outgrowth of excitatory neurons, but not inhibitory neurons.

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.

GABA(γ-aminobutric acid)는 비단백질성 아미노산으로 뇌기능 촉진, 신경안정 및 혈압저하 효과 등의 생리 활성 기능물질로 알려져 있다. GABA 고함유 배추김치를 제조하기 김치제조 시 사용되는 부재료로 표고버섯, 느타리, 팽이, 큰느타리, 양송이 등 국내산 버섯류를 수집하여 열수 및 5% trichloroacetic acid 로 추출하고 HPLC을 이용하여 GABA 함량을 분석하였다. 버섯류 중에는 양송이 39.46 mg 100 g-1, 큰느타리 31.63 mg 100 g-1, 느타리 70.75 mg 100 g-1로 순으로 느타리 버섯이 가장 높은 GABA 함량을 나타내어 김치 부재료로 사용하였다. 느타리 버섯이 함유된 김치육수에 GABA 생성 Lactobacillus 유산균을 접종하고 30°C에서 24시 간 발효시킨 육수를 이용하여 김치를 제조한 후, 4°C에서 숙성 기간별 GABA 및 glutamic acid 함량변화를 분석한 결과, 김치는 초기에 비해 19일 후 GABA 함량이 88.59 mg g-1 증가하였고, 김치국물도 173.79 mg 100 mL-1의 증가효과를 보였다. 이상의 결과를 통해 배추김치 제조시 부재료로 느타리 버섯과 실온에서 Lactobacillus 균을 접종하여 발효한 육수를 사용시 배추김치의 GABA함량을 증진시키는 효과를 얻을 수 있었다.

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.

The present study investigated the role of central GABAA and GABAB receptors in orofacial pain in rats. Experiments were conducted on Sprague-Dawley rats weighing between 230 and 280 g. Intracisternal catheterization was performed for intracisternal injection, under ketamine anesthesia. Complete Freund's Adjuvant (CFA)-induced thermal hyperalgesia and inferior alveolar nerve injury-induced mechanical allodynia were employed as orofacial pain models. Intracisternal administration of bicuculline, a GABAA receptor antagonist, produced mechanical allodynia in naive rats, but not thermal hyperalgesia. However, CGP35348, a GABAB receptor antagonist, did not show any pain behavior in naive rats. Intracisternal administration of muscimol, a GABAA receptor agonist, attenuated the thermal hyperalgesia and mechanical allodynia in rats with CFA treatment and inferior alveolar nerve injury, respectively. On the contrary, intracisternal administration of bicuculline also attenuated the mechanical allodynia in rats with inferior alveolar nerve injury. Intracisternal administration of baclofen, a GABAB receptor agonist, attenuated the thermal hyperalgesia and mechanical allodynia in rats with CFA treatment and inferior alveolar nerve injury, respectively. In contrast to GABAA receptor antagonist, intracisternal administration of CGP35348 did not affect either the thermal hyperalgesia or mechanical allodynia. Our current findings suggest that the GABAA receptor, but not the GABAB receptor, participates in pain processing under normal conditions. Intracisternal administration of GABAA receptor antagonist, but not GABAB receptor antagonist, produces paradoxical antinociception under pain conditions. These results suggest that central GABA has differential roles in the processing of orofacial pain, and the blockade of GABAA receptor provides new therapeutic targets for the treatment of chronic pain.