• 한국식품영양학회지
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• 제8권4호
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• pp.275-279
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• 1995

A bacterium L-10 which produce mush of glutamic acid was Isolated from soil and identified as the genus Pserdomonas. The maximal glutamic acid production was obtained when the strain was cultured at 3$0^{\circ}C$ for 30 hrs in the optimal medium containing 5% glucose, 0.5% each of urea and yeast extract, 0.1% K2HP04, 0.02% MgSO4.7H20, 0.3% (NH, )rHP04, 0.5ug/l biotin and Initial pH 7.0, and then final glutamic acid production under the above conditions was 1.2mg/ml of cell cultures.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권4호
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• pp.289-295
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• 2005

In this study, the cultural medium used for the efficient production of $\gamma$-PGA with a newly isolated Bacillus sp. RKY3 was optimized. It was necessary to supplement the culture medium with L-glutamic acid and an additional carbon source in order to induce the effective production of $\gamma$-PGA. The amount of $\gamma$-PGA increased with the addition of L-glutamic acid to the medium. The addition of 90 g/L L-glutamic acid to the medium resulted in the maximal yield of $\gamma$-PGA (83.2 g/L). The optimum nitrogen source was determined to be peptone, but corn steep liquor, a cheap nutrient, was also found to be effective for $\gamma$-PGA production. Both the $\gamma$-PGA production and cell growth increased rapidly with the addition of small amounts of $K_2HPO_4$ and $MgSO_4\cdot7H_{2}O$. Bacillus sp. RKY3 appears to require $Mg^{2+}$, rather than $Mn^{2+}$, for $\gamma$-PGA production, which is distinct from the production protocols associated with other, previously reported bacteria. Bacillus sp. RKY3 may also have contributed some minor $\gamma$-PGA depolymerase activity, resulting in the reduction of the molecular weight of the produced $\gamma$-PGA at the end of fermentation.

• 한국식품영양학회지
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• 제25권3호
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• pp.677-684
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• 2012

Poly-${\gamma}$-glutamic Acid(${\gamma}$-PGA)를 다량 생산하는 균주를 우리나라의 전통발효식품인 청국장으로부터 Bacillus subtilis GS-2를 분리하였다. 이 균은 glutamic acid 의존형 균으로, 이 균에 의한 ${\gamma}$-PGA 생산 최적 조건을 검토한 바, 단순배지(L-glutamic acid 2.0%, glucose 1.0%, $NH_4Cl$ 0.5%, $KH_2PO_4$ 0.05%, $MgSO_4$ $7H_2O$ 0.01%, pH 7.0)로 진탕배양(220 rpm) 하였을 때, 배양시간 48시간, 최적온도 $33^{\circ}C$, 그리고 초기 pH 6.5로 나타났다. 영양원으로 glutamic acid 3%, sucrose 3%, $NH_4Cl$ 0.25%, $KH_2PO_4$ 0.15%, $MgSO_4$ $7H_2O$ 0.015%에서 ${\gamma}$-PGA 최대 생산량이 31.0 $g/{\ell}$이었다.

• 환경위생공학
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• 제14권3호
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• pp.107-115
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• 1999

The effectiveness of resting cells of a photosynthetic bacterium, Rhodospirillum rubrum N-1, was investigated on the production of extracellular ${\delta}-aminolevulinic$ acid(ALA). The ALA generating system required 3hr-incubation in the presence of 10mg of resting cells per ml to obtain the maximal yield of extracellular ALA. and also, under this condition the effect of ALA inducers, i.e., 30mM levulinic acid (LA) and L-glutamic acid($C_5$ pathway precursor) was relatively higher than that of produced extracellular ALA($83{\mu}M$). The volume of system and proper cell density appeared to be important factors for the effective production of extracellular ALA.