• BMB Reports
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• 제35권6호
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• pp.568-575
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• 2002

An $\alpha$-amylase (EC 3.2.1.1) was purified that catalyses the production of a high level of maltose from starch without the attendant production of glucose. The enzyme was produced extracellularly by thermophilic Streptomyces sp. that was isolated from Thailand's soil. Purification was achieved by alcohol precipiation, DEAE-Cellulose, and Gel filtration chromatographies. The purified enzyme exhibited maximum activity at pH 6-7 and $60^{\circ}C$. It had a relative molecular mass of 45 kDa, as determined by SDS-PAGE. The hydrolysis products from starch had $\alpha$-anomeric forms, as determined by $^1H$-NMR. This maltose-forming $\alpha$-amylase completely hydrolyzed the soluble starch to produce a high level of maltose, representing up to 90%. It hydrolyzed maltotetrose and maltotriose to primarily produce maltose (82% and 62%, repectively) without the attendant production of glucose. The high maltose level as a final end-product from starch and maltooligosaccharides, and the unique action pattern of this enzyme, indicate an unusual maltose-forming system. After the addition of the enzyme in the bread-baking process, the bread's volume increased and kept its softness longer than when the bread had no enzyme.

• KSBB Journal
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• 제9권4호
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• pp.418-427
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• 1994

For the production of ${\alpha}$-amylase cloned from Bacillus licheniformis expressed in E. coli, cultivating factors including the concentrations of glucose, maltose and acetic acid were investigated. The results were as follows: 1) Maximum ${\alpha}$-amylase yield and maximum specific production rate obtained from glucose source were better than those achieved from maltose source. 2) The optimum production yield of ${\alpha}$-amylase was obtained at 1.0ml/$\ell$ or less of initial acetic acid concentration.

• 미생물학회지
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• 제6권3호
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• pp.81-86
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• 1968

1. Amylolytic enzyme activities of Asp. oryzae and Asp. oryzae var. fulvus using the glucose as the carbon sources increased remarkably according to the decrease of the residual sugars. 2. The amylase productions of Asp. oryzae and Asp. oryzae var. fulvus were increased and enhanced when the organisms lave belen cultured in modified Koji media containing maltose as adaptive substrate. However, being devoid of maltose the level of amylase activities were lower and the begining of the production was prolonged. 3. The effects of C-sources on the amylase production of them were observed. The level of amylase activity varied with C-sources and their concentrations Marked increase of amylase production was afforded by starch and maltose. The effects of citric acid and tartaric acid were little or nothing. 4. Using the sucrose and lactose as the adaptive substrates both strains show the maximum amylolytic enzyme activities at the 3% concentrations of those sugars.

• KSBB Journal
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• 제11권2호
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• pp.125-131
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• 1996

Bacillus amyloliquefacieus 01용한 회분식 배양시 탄소원인 maltose와 glucose에서 저해제 acetic a acid, lactic acid가 세포성장과 생성물 생성에 미치 는 영향에 대해 검토한 결과, acetic acid가 저해제 로 작용함을 확인하였고, acetic acid 첨가시 초기농 도가 증가할수록 세포성장은 현저하게 감소되었다. ${\alpha}$-Amylase 생성 최대치는 maltose $10g/\ell$ 의 경우 a acetic acid 초기농도 $0.5g/\ell$ 일때 24시간 배양시에 l25unit/ml로 가장 높았고, glucose $10g/\ell$ 의 경우 acetic acid 초기놓도 $2.0g/\ell$ 일때 20시간 배양시에 331.55unit/ml로 가장 높았다. Acetic acid 초기농 도가 과량 일때는 세포의 성장이 최저 상태이고, ${\alpha}$-amylase 생성도 급격히 감소하였다. 저해제로 ace­t tic acid 첨가시 탄소원인 maltose와 glucose를 비 교하면 glucose에서 maltose 보다는 세포가 더 성장되었고, ${\alpha}$-amylase의 생성도 더 많게 나타났으며, 두 가지 탄소원에 다같이 저해 작용을 나타냈다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.251-254
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• 2000

Effect of carbon sources including agro-industrial byproduct on cell growth and production of curdlan by Agrobacterium sp. ATCC 31749 was investigated. Maximal production of curdlan was obtained when the carbon source was sucrose. The conversion rate of curdlan from 2% (w/v) sucrose was 59%. Glucose, mannose and maltose were also found to be good carbon sources for production of curdlan. Production of curdlan increased up to 3% (w/v) glucose as the carbon source and then decrease as the concentration of glucose increased. The major components of agro-industrial byproduct (AIB) were glucose, maltose, and maltose, and maltotriose. Agrobacterium sp.ATCC 31749 utilized up to 25% (v/v) AIB and produced curdlan with 29.8g/1.

• Journal of Microbiology and Biotechnology
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• 제16권2호
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• pp.325-329
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• 2006

Leuconostoc mesenteroides B-742 fermentations with maltose as an acceptor were tested for glucooligosaccharides and mannitol co-production. Leuconostoc oligosaccharides were produced that were oligomers with a size range of DP 2 to 7 and were primarily DP 3, 4, 5, and 6, containing mainly ${\alpha}-1,4$ and ${\alpha}-1,6$ linkages. Maltose was linked to the reducing end of the isomaltosyl residues. The $Ca^{2+}$ form of cation-exchange column could separate glucooligosaccharides from byproducts.

• 미생물학회지
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• 제25권4호
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• pp.360-366
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• 1987

For the production of pullulan from the high concentration of sugar, the utilization of sugars by a pullulan-producing fungus, Aureobasidium pullulans was examined. A. pullulans showed the different utilization patterns for sugars such as sucrose, maltose, and maltotriose. Especially for maltotriose, the hydrolysis of sugar was accompanied by a transferase activity. Glucose and maltose showed the inhibitory effect on the cell growth and the pullulan production at the sugar concentration higher than 0.28M, but sucrose showed the inhibitory effect at the sugar concentration higher than 0.14M. Among the sugars examined, sucrose gave the best result for the pullulan production. 27.5g/l of pullulan was obtained from 5% sucrose.

• 한국식품과학회지
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• 제30권1호
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• pp.110-117
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• 1998

고정화 transglucosidase (TG)를 이용한 충진형 반응기를 만들어 isomaltooligosaccharides (IMO)의 연속생산 가능성을 살펴보고 기질용액의 농도와 유속에 따른 반응산물의 생성패턴과 운전안정성을 조사하였다. 고정화 TG에 의한 IMO의 생성패턴은 soluble TG의 경우와 동일하였다. 충진형반응기에 의해 생성된 포도당과 isomaltose의 농도는 기질인 maltose 용액의 농도와 종류에 관계없이 유속의 증가에 따라 지속적으로 감소되는 경향을 보였고 isomaltotriose 역시 10% 기질용액을 사용한 경우를 제외하고 같은 경향을 보였다. 반면, panose의 농도는 유속의 증가에 따라 증가하다가 감소하는 경향을 보였다. 기질농도가 10% 일 때, IMO의 최대수율은 2 mL/min 유속에서 52.1%였고, 20%와 30% (w/v)일 때는, $0.5{\sim}1.0\;mL/min$ 유속에서 각각 $39.0{\sim}38.0%,\;12.1{\sim}14.2%$의 최대수율을 보였다. 20%의 maltose를 함유한 조제당화액을 사용했을 때의 수율은 유속이 0.5 mL/min일 때 36.3%였다 본 충진형반응기는 $55^{\circ}C$에서 안정되게 운전되었다. 144시간 운전후에 초기 활성의 85%, 288시간 경과후에도 약 65%의 활성이 잔존하였다. 본 실험결과로 보아 IMO를 생산하기 위해 고정화 TG를 이용한 충진형반응기를 적용하는 것은 가능성이 클 것으로 예상되었다.

• Journal of Microbiology and Biotechnology
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• 제28권6호
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• pp.902-908
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• 2018

Optimization of the culture medium to maximize menaquinone-7 (MK-7) production by Bacillus subtilis strain KCTC 12392BP in static culture was carried out using statistical experimental methods, including one factor at a time, fractional factorial design, and response surface methodology (RSM). Maltose (carbon source), tryptone (nitrogen source), and glycerol (activator) were identified as the key medium components for MK-7 synthesis by the fractional factorial design, and were selected for statistical optimization by RSM. The statistical analysis indicated that, in the range that was studied, maltose, tryptone, and glycerol were all critical factors having profound effects on the production of MK-7, with their coefficients for linear and quadratic all significant at the p < 0.05 level. The established model was efficient and feasible, with a determination coefficient ($R^2$) of 0.9419. The predicted concentrations of maltose, tryptone, and glycerol in the optimal medium were determined as 36.78, 62.76, and 58.90 g/l, respectively. In this optimized medium, the maximum yield of MK-7 reached a remarkably high level of $71.95{\pm}1.00{\mu}g/ml$ after 9 days of static fermentation, which further verified the practicability of this optimized strategy.

• 약학회지
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• 제42권1호
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• pp.46-52
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• 1998

Retroviral integrase is required for integration of viral DNA into the host cell chromosome. Human immunodeficiency virus type-1 integrase was partially purified as a part of a fusion protein linked to a maltose-binding protein and characterized in terms of an endonucleolytic activity. The concentration of the fusion protein purified through an amylose column was about 12mg/ml. Indicating that the solubility of the fusion protein is highly increased by the presence of a maltose-binding protein, considering that the integrase protein alone is poorly solubilized. The endonucleolytic activity of the fusion protein was detected at 0.1 to 1.OmM $Mn^{++}$ ion, but not at any concentrations tested of $Mn^{++}$ ion.