• Korean Journal of Environment and Ecology
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• v.14 no.3
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• pp.205-211
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• 2000

본연구는 조경소재로 이용가능성이 크지만 현재 자생지가 파괴되어 복원이 요구되고 있는 야생자란의 대량번식을 위해 무균배양시 배지 내 담함량의 변화와 펩톤, 트립톤 등의 첨가가 종자발아와 계대배양 후 유식물의 생육에 미치는 영향을 알아보고자 실시하였다. 배지 내 펩톤과 트립톤의 첨가는 발아에 영향을 주지는 않았지만, 당의 함량은 그 농도가 10g/L까지 증가함에 따라 발아율을 높였다. 또한 발아 후 유식물의 생육시 당의 첨가는 뿌리의 생육을 두드러지게 향상시켰으며, 생체중도 거의 2~3배정도 많았다. 하이포넥스 배지(대조구)에서는 높은 발아율을 보였지만 유식물의 생육은 트립톤 첨가배지(2g/L)에서 많았는데 엽수, 뿌리수, 엽장 근장, 생체중 등이 모두 다른 처리구의 2~3배에 이르는 초기생육을 보였다. 계대배양 이후의 생육상은 펩톤 첨가배지에서 가장 많은 생육량을 보였는데 특히 엽장과 엽폭 그리고 근장이 다른 처리구보다 월등히 높은 경향을 나타냈다. 생체중도 한 개체당 0.18g으로 가장 높게 나타나 펩톤의 첨가가 계대배양 이후의 생육을 크게 촉지시키는 것으로 나타났다. 결론적으로 하이포넥스 배지에 트립톤 2g/L를 첨가하였을 때 발아율과 유식물의 생육이 다른 배지에 대해 매우 양호한 것으로 나타나 자생 자란의 종자발아용 배지로 가장 적당한 것으로 사료된다. 그리고 이후 계대배양시에는 펩톤의 첨가 (3g/L)가 유식물의 생육을 가장 촉진시키는 것으로 나타났다.

• The Journal of Natural Sciences
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• v.8 no.1
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• pp.33-39
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• 1995

Klebsiella sp. L-10 was treated with physical and chemical mutagens, and one of the NTG mutant which increased hyaluronic acid complex yield 2.5 folds was selected. The yield of hyaluronic acid complex from Klebsiella sp. L-10 NTG 50 mutant reached maximum level I the YPD medium containing 0.1% yeast extract, 3% Bacto-tryptone, 3% dextrose, each 30mM of $K_2HPO_4$ and $KH_2PO_4$ (pH 6.0-6.5) with shaking culture at $37^{\circ}C$ for 24 hrs, and 2900mg of hyaluronic acid complex per litre of culture was produced under the above condition.

• Microbiology and Biotechnology Letters
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• v.9 no.1
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• pp.29-34
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• 1981

To maximize the production of penicillin amidase from Estherichia coli (ATCC 9637), the media composition and several factors affecting the engyme production during fermentation were studied. The optimal media composition was found to be; 3.5% tryptone, 1.5% monosodium glutamate and 0.5% yeast extract. The addition of 0.15% phenylacetic acid as an enzyme inducer at the initial stage of cultivation increased the engyme productivity about 5 fold. It was found that the engyme activity reached maximum within 16hr of cultivation. The maximum production of the enzyme obtained was about 102.5 units/l broth under the optimized condition. The enzyme production was markedly increased by the optimization as compared with those previously reported.

• KSBB Journal
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• v.11 no.4
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• pp.462-469
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• 1996

Biosolubilization of an Australian lignite was investigated by using Streptomyces viridosporus and Poria cocos. In order to solubilize coals effectively they were pretreated by nitric acid both in surface and liquid cultures. The optimum growth pH was 7.5 for S. viridosporus and 4.5 for P. cocos. The effects of various carbon, nitrogen and metal sources on overall solubilization were also studied. Solubility increased with the addition of urea for S. viridosporus, and peptone and tryptone for P. cocos. However carbon and metal sources had little or negative effects on solubilization. Maximum amount of coal solubilized was 85%(w/w) in a batch fermentation culture. Extracellular materials produced by micro-organism were found to be responsible for the coal solubilization. Approximately 70 to 80% of coal solubilization was determined to be the result of non-enzymatic reactions, and the rest to be the result of enzymatic reactions. Characteristics of the solubilized coal were compared with those of original coal and pretreated coal by the approximate and ultimate composition analysis, and IR-spectrum analysis. The spectroscopic results showed that the mechanism of coal solubilization was caused by continuous oxidation.

• Korean Journal of Food Science and Technology
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• v.49 no.6
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• pp.610-616
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• 2017

${\gamma}$-Glutamyltranspeptidase (GGT, EC 2.3.2.2) transfers ${\gamma}$-glutamyl moiety from glutamine to amino acids or peptides and hydrolyzes glutamine to glutamate and ammonia. In order to overproduce ${\gamma}$-glutamyltranspeptidase from Bacillus amyloliquefaciens (BAGGT), the encoding gene was cloned and expressed in Bacillus subtilis. The productivity of BAGGT in Bacillus subtilis was improved by 42-fold by using a dual-promoter system that was generated by combining promoters from B. subtilis ${\alpha}$-amylase and BAGGT genes. Through optimization of medium composition by Plackett-Burman design and central composition design, BAGGT was produced at $18.3{\times}10^7U/L$ of culture in the optimized medium. Compared to previously used Luria-Bertani medium, the optimized culture medium (15 g/L molasses, 60 g/L corn steep liquor, 6 g/L yeast extract, 4 g/L NaCl, 6 g/L $K_2HPO_4$, and 2 g/L $KH_2PO_4$), resulted in a 4.3-fold increase in production of BAGGT.