• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1975년도 추계학술발표회
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• pp.182.1-182
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• 1975

L-Glutamic acid 발효생산에 있어서 당밀대체의 목적으로 Tapioca전분의 효소당화액의 이편 가성을 검토하여 다음과 같은 결과를 얻었다.(중략)

• 한국패류학회지
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• 제19권2호
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• pp.95-106
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• 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%).

• Applied Biological Chemistry
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• 제36권3호
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• pp.184-190
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• 1993

Rhodobacter sphaeroides 균주가 생산하는 ${\delta}-aminolevulinic\;acid(ALA)$의 생산성에 관하여 in vivo, in vitro 상에서 기질 및 관련 화합물을 이용하여 검토하였다. $C_5\;ALA$ 생합성계에 의한 ALA yield 대비의 $C_4$ 생합성계에 의한 비율은 in vive 상에서 0.78인 반면, in vitro 상에서의 비율은 1.37이었다.$C_4\;C_5$ 각 계의 기질 첨가 배양에 의한 cell-free system의 $C_4,\;C_5$ 계의 발현도는 미첨가 배양에 의한 system과 비교하여 각각 1.35, 1.52로 증가하였으나, 증가한 계에 대한 상대계의 발현도가 억제되어, $C_4$ 와 $C_5$ 계가 각각 0.91, 0.83으로 나타났다. ${\gamma}-Glutamyl\;derivatives$의 세포내 uptake rates는 L-glutamic acid를 기준으로 비교해서 D-glutamic acid, 0.55: D-glutamine, 0.5: L-glutamine, 0.4: ${\gamma}-L-glutamyl\;ethylester$, 0.3: GSH 및 Glu-pNA, 0의 순서를 보였다. Uptake rate와 관계없이 in vivo 상에서 L-과 D-glutamine이 L-, D-glutamic acid보다 균체 외 ALA의 생산에 있어서 각각 높은 yield의 효과를 보였다.

• Journal of Microbiology and Biotechnology
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• 제29권7호
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• pp.1061-1070
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• 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.

• 대한화학회지
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• 제34권2호
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• pp.203-210
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• 1990

의약 전달체에 사용되는 생체분해성 고분자로서 L-lactic acid 와 L-glutamic acid가 각기 다른 조성비로 이루어진 공중합체를 합성하였다. Poly (L-lactide)는 zink oxide를 이용하여 합성하였으며, Poly (L-lactide) 말단에 3-Amino-l-propanol을 도입시킨 다음 이미 합성된 γ-benzyl-L-glutamate-N-carboxyanhydride (γ-BLG-NCA)를 개환중합시켜서 block copoly (L-lactide-γ-benzyl-L-glutamate)를 합성하였다. NMR로써 L-lactide와 γ-BLG-NCA가 서로 일정한 비율로 이루어진 공중합체가 합성되었음을 확인하였으며, 생성된 공중합체들의 열적성질은 시차주사열량계법 및 열무게 측정법으로 조사하였다.

• Animal Bioscience
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• 제34권12호
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• pp.1963-1973
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• 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.

• Applied Biological Chemistry
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• 제43권1호
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• pp.29-33
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• 2000

장류 품질개선의 일환으로 된장, 고추장 및 간장 발효물에 glutaminase첨가 효과를 조사하기 위하여 숙성기간에 따른 L-glutamic acid와 아미노태질소(AN) 함량을 분석하였다. 효소첨가구의 발효초기에 대한 발효 45일 째의 glutamic acid의 함량 증가는 고추장이 671.8%, 간장 298.1% 및 된장 193.4% 순으로 높았다 무첨가구에 대한 발효 45일째의 glutamic acid의 함량 증가는 고추장이 363.1%, 된장 159.2%, 간장 35.7% 순으로 높아 고추장 발효물에 대한 glutaminase 첨가 호과가 가장 높아 3배 이상 되었다 또한 glutaminase 첨가시 아미노태질소 함량의 발효초기에 대한 증가효과는 45일 째에 고추장이 216.0%, 간장 120.8% 및 된장 84.5% 순으로 높았고, 무첨가구와 비교하였을 경우 발호 45일에 된장이 40.3%, 고추장 35.7%, 간장 8.4% 순으로 증가하였다. glutaminase첨가 제품에 대한 관능검사 결과 효소를 첨가하지 않은 제품에 비하여 맛과 향, 기호도에서 더 좋은 효과를 나타내었다.

• 한국미생물·생명공학회지
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• 제3권1호
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• pp.7-15
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• 1975

The possibilities of utilizing acid-hydrolyzate of "Sliced and dried sweet potatoes" as a carbon source for the microbial production of L-Glutamic Acid(L-GA) with Micrococcus glutamicus were investigated and the results showed as follows： 1) The highest hydrolysis rate, 74.6% of the reducing sugar based on the weight of dry matter, was obtained when the sweet potatoes were hydrolyzed with 0.8% of HCI at 2.0kg/$cm^2$ for 30 minutes. The most favorable hydrolyzate for the growth of the cells, however, was found to be the one obtained by treating the sweet potatoes with 0.5% HCI at 2. 0kg/$cm^2$ for 10 minutes. Reducing sugar content of the hydrolyzate was 10% as glucose. 2) Biotin content of the hydrolyzate was 25$\mug$/1 and it was proved to be excess in amount for the L-GA production. 3) The effects of addition of antibiotics, alcohols and fatty acid esters on the L-GA production were tested in the biotin excess medium. The production of L-GA was most increased to 32.5g/l with the addition of 10 I. U. of penicillin per ml. to the culture medium at 4 hours after inoculation. But the addition of alcohols, especially fatty acid esters, showed no significant effects. 4) Among the organic nutrients tested. " Gluten acid hydrolyzate" greatly enhanced the production of L-GA adding it＇s concentration of 1.0% to the medium. 5) The maximum production of L-GA resulted in 35g/1 when the cells were grown for 48 hours in the hydrolyzate medium supplemented with 1.0% of "Gluten acid hydrolyfate" and with 10 I. U. of penicillin per ml added at 4 hours after cultivation.

• 한국식품영양학회지
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• 제17권4호
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• pp.374-381
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• 2004

우유에 감자분말을 첨가하여 2종의 Lactobacillus bulgaricus, Streptococus thermophillus 젖산균을 혼합하여 배양할 경우 젖산발효가 어떤 메카니즘에 의해 촉진되며 요구르트의 품질에 미치는 영향을 조사코자 젖산균의 산생성 능력과, 요구르트의 점도, 유리아미노산 및 관능검사를 하였다. 0.5％(w/w) 감자분말을 첨가하여 배양한 젖산발효의 경우 무 첨가군에 비하여 산도는 높았고, pH는 낮았으며 점도는 증가되었다. Streptococus thermophillus와 Lactobacillus bulgaricus를 혼합배양한 경우 산의 생성은 가장 높았으며, 각각의 균을 단독 배양 시에는 S. thermophillus가 L. bulgaricus보다 산 생성도가 높았다. 감자분말을 첨가하여 각각의 균을 배양한 경우 L. bulgaricus와 S. thermophiilus 균주에서 모두 lysine의 이용률은 높았으며, L. bulgaricus는 glutamic acid를 다량 생성한 반면, S. thermophillus는 glutamic acid를 소모하였다. 감자분말을 첨가한 요구르트 관능평가에서 조직감은 향상되었고, 색, 맛, 후미 및 전체적인 기호도는 다소 저하되었다. 이상의 결과로부터 L. bulgaricus는 S. thermophillus 균주가 요구하는 유리 glutamic acid을 공급함으로써 S. thermophiilus의 생육이 촉진되어 감자분말 첨가 요구르트의 발효기간을 단축시킨 것으로 사료된다.

• 한국버섯학회지
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• 제15권1호
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• pp.38-44
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• 2017

최근 식용과 약용버섯으로 각광을 받고 있는 꽃송이버섯(Sparassis latifolia 혹은 S. crispa)은 베타-글루칸이 풍부하여 다양한 생리활성을 나타낸다고 알려져 있다. 꽃송이버섯에 다량 포함된 베타-글루칸과 더불어 뇌기능을 증진시킬 수 있는 영양성분이 보강된다면 약용버섯의 기능성이 더욱 증대되어 농가소득 증대와 국민 건강증진에 큰 기여를 할 것으로 판단된다. 본 연구에서는 꽃송이버섯 균사체 배양 시 아미노산을 첨가하였을 시 균사 생장이 촉진됨과 함께 GABA 함량이 증대되었고, ${\beta}-glucan$ 함량에는 유의적인 효과가 없는 것을 확인하였다. 균사의 생장에는 glutamic acid와 ornithine 모두 효과가 있었으나, GABA 함량에 대해서는 glutamic acid의 첨가가 훨씬 효과적임을 확인하였다. 이는 꽃송이버섯 균사체의 GABA-shunt에 glutamic acid가 영향을 미친 것으로 사료된다. 생성된 GABA의 소멸과 다른 화합물의 신규 생성에 대해서는 아직 결과를 도출하지 못하였으므로, 이 부분에 대한 추가 연구가 필요하리라 사료된다.