• 한국미생물·생명공학회지
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• 제33권1호
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• pp.41-50
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• 2005

Leu. mesenteroides KCCM 35471을 변이처리하고 젖산과 초산이 2:1로 함유된 유기산 조정 배지에서 screening을 하여 유기산 내성 변이균주 M-200을 얻었다. 내산성 개량균주 M-200과 야생균주 LM-W는 $10^{\circ}C\~30^{\circ}C$ 온도범위와 pH $3.5\~4.5$의 영역에서 생육 특성에 대해 실험을 행하였다. 내산성 변이균주 M-200의 경우에는 HCI로 조절한 배지에서는 $10^{\circ}C$, pH 3.5영역에서도 증식하였다. 유기산으로 조절한 배지에서는 $10^{\circ}C$, pH 3.8의 영역까지 증식하였다. 내산성 변이균주 M-200과 야생균주 LM-W를 김치에 starter로 첨가하여 $10^{\circ}C$에서 발효시킨 결과를 살펴보면, 내산성 변이균주 M-200은 김치 발효가 끝나는 시점까지 산도 0.55 이하를 유지하였다. 이는 김치의 적숙 기간을 산도가 $0.4\~0.75\%$일 때로 본다면 내산성 변이균주 M-200을 첨가한 군은 발효기간 내내 적숙기를 유지한다는 것을 알 수 있었다. 또한 이를 야생균주 LM-W를 첨가한 군과 비교해보면 가식기간이 약 3.5배 연장됨을 볼 수 있었다. 그러나 지나친 M-200의 생육으로 Lac. plantarum의 생육이 떨어지고 김치의 산도가 올라가지 못하고 신맛이 부족하여 김치의 관능이 떨어졌다. 유기산 분석에 있어서도 젖산의 생산이 대조군에 비해 발효 21일째부터는 약 절반 정도 밖에 생산하지 못하였다 따라서 starter 첨가량 조절과 다른 변이주 들과의 혼합첨가를 한다면 좋은 관능을 갖는 김치를 생산할 수 있을 것으로 생각되었다.

• Journal of Microbiology and Biotechnology
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• 제6권4호
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• pp.265-269
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• 1996

An isolate of Streptomyces rochei synonym was found to produce antibiotics with narrow anti-microbial spectrum against Streptococcus and Xanthomonas sp. Among the antibiotic complex produced by the strain, the main active compound was isolated, and its physico-chemical properties and biological activities were investigated. Molecular weight of the compound was determined to be ${[M+H]}^+$ 797 (FAB-MS). UV, $^1H \;and\;^{13}C$ NMR, and IR spectra suggested that the compound is a kirromycin-like aurodox group antibiotic. However, the anti-microbial spectrum of the main compound was slightly different from that of kirromycin. In addition, it was newly found that kirromycin showed a selective anti-microbial activity against Streptococcus pyogenes and phytopathogenic Xanthomonas sp.

• 한국환경보건학회지
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• 제24권3호
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• pp.70-76
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• 1998

Activation bacteria, identified from commercial microbial products, were applied to leachate treatment. Total seven strains of bacteria Enterobacteriaceae spp. (5), Bacillus sp. (1), Aeromonas sp. (1) were seeded in the leachate and cultured in the shaking incubator at 25$^{\circ}$C and 250 rpm. While cultured, they were sampled in given time intervals and the removal rates of SS, COD, BOD, T-N.and T-P were measured an indicators of leachate treatment. Through the screening test, four of 7 strains of bacteria were considered to be effective and they were named as "effective group". The capability of leachate treatment was observed on three different groups of bacteria single, effctive, and total mixed. The result showed that the removal rates of COD and SS for the total mixed group were 64 and 71% respectively. BOD removal rate was reached nearly 99% by seeding of effective griup and removal rates of T-P and T-N were 83 and 82% respectively. However seeding of single strain was less effective than that of any mixed group in leachate treatment.

• Natural Product Sciences
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• 제5권3호
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• pp.151-153
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• 1999

(+)-Hernandulcin is a sweet bisabolane-type sesquiterpene first isolated from Lippia dulcis Trev. (Verbenaceae). This oily compound is 1000-1500 times sweeter than sucrose but with poor solubility in water. Microbial transformation was employed to improve its water solubility, and a variety of microorganisms were screened for their ability to convert (+)-hernandulcin to more polar metabolites. Scale-up fermentation with Glomerella cinguiata, a fungal strain, has resulted in the isolation of a more polar metabolite (2).

• 생약학회지
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• 제15권1호
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• pp.39-42
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• 1984

To examine stability and a separate quantitative method of a mixed preparation of lactic acid bacteria, a capsule containing Lactobacillus acidophilus, Lactobacillus bulgaricus and Streptococcus thermophilus was suspended and diluted in sterile water. After the diluted suspension was spread on three media of tryptone glucose extract agar, MRS agar and MRS-sucrose agar, their colonies appeared and were counted. The viable counts exceeded the minimum number of the three bacteria and showed that the mixed preparation was stable at least for 18 months. The results also showed that a separate quantitation of viable cells of the each strain was feasible.

• 한국미생물·생명공학회지
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• 제23권4호
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• pp.405-410
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• 1995

In order to screen dextranase with high dextranolytic activity from microbial origins, dextranase producing fungal isolates were isolated from soil of the Taeion area. 197 strains with dextranolytic activities were isolated, out of which 3 strains with high dextranolytic activities were selected in the first screening. A strain (GR-98) with a best dextranolytic activity was selected in the second screening. The strain was identified to be similiar Aspergillus ustus by the morphological and cultural characteristics. The optimum culture temperature and initial pH for the dextranase production of the strain was 30$\circ$C and 7.0, respectively. The optimum culture medium was composed of 2% dextran, 0.3% KNO$_{3}$, 0.05% K$_{2}$HPO$_{4}$, 0.02% MgSO$_{4}$-7H$_{2}$O, 0.05% KC1, and 2.5 $\mu$g/ml pyridoxamine, and the enzyme production was maximum when the strain was subcultured at 30$\circ$C for 7 days.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.335.3-336
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• 2002

To find ${\alpha}$-Glucosidase Inhibitors produced by Actinomycetes, 20 soil samples were tested and 53 Actimycetes were isolated. One of 53 Actinomycetes (strain PM718) showed very potent inhibitory activity in vitro. The morphological and physiological characteristics of strain PM 718 were investigated. The spore morphology. spore chain morphology and spore surface were observed by scanning electron microscope. The inhibitory activity of strain PM718 in vivo has been studied in mice made hyperglycemia by Streptozotocin treatment. The strain PM718 showed signficant reduction of blood glucose level(more than 30%) in mice loaded with maltose.

• 식품산업과 영양
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• 제2권1호
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• pp.16-21
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• 1997

Microbial of enzymatical methods are suitable for production of rare monosaccharides. Using oxidation and reduction ability of Microorganisms, various rare ketoses and polyols can be produced, for example D-tagatose from galagtitol by Enterobacter agglomerans strain 221e. L-tagatose from galactitol by Klebsiella pheumonias strain 40b, L-psicose from allitol by Gluconobacter frateurii IFO 3254, D-talitol from d-tagatose by Aureobasidium pullulans strain 113B, allitol from D-psicose by Enterobacter agglomerans strain 221e and so on. We can produce various rare aldoses and ketoses using aldose isomerases, for example L-galactose from L-tagatose by D-arabnose isomerase, and L-ribose from L-ribulose by L-isomerase, and so on. D-Tagatose 3-epimerase of Pseudomonas sp. ST-24 is very useful for preparationof various rare ketoses, for example D-psicose from D-fructose, D-sorbose from D-tagatose, L-fructose, from L-psicose and so on. Using polyol dehydrogenases, aldose isomerases and D-tagatose 3-epimerase, we can design the suitable for production of a certain rare monosaccharide from a suitable substrate.

• 생약학회지
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• 제15권1호
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• pp.15-23
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• 1984

To find antimicrobial strains of the soil microorganisms in Korea, they were isolated from the soil samples of different locations and screened for antibiotic activity against several standard microbes. An isolate among them had an antibacterial activity against gram-positive bacteria. The examination of its morphological and biochemical characteristics according to the International Streptomyces Project methods showed that it belongs to the genus Streptomyces. The strain was named DMC-72. The strain appears to be a new strain when it was compared with the species within the genus which have been so far reported. The antibiotic metabolite of the strain was produced in submerged culture method. It was found to be a quinone compound and was named soulomycin. This strain was also found to produce an ${\alpha}-amylase$ inhibitor in the submerged culture.

• 한국미생물·생명공학회지
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• 제47권4호
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• pp.565-573
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• 2019

섬유소계 바이오매스로부터 바이오 연료 등과 같은 유용한 물질을 생산하기 위해서는 바이오매스로부터 유래하는 혼합당을 효과적으로 대사할 수 있는 균주의 개발이 필수적이다. 본 연구에서는 xylose를 대사가 가능한 효모인 P. stipitis를 적응진화하여 cellobiose 대사효율이 향상되고 cellobiose와 xylose를 동시에 대사할 수 있는 균주를 개발하고자 하였다. 총 10회의 계대배양을 통해 얻어진 진화된 P. stipitis 돌연변이 균주는 모균주에 비해 6배 이상 증가된 cellobiose 대사속도를 나타내었으며 ethanol 생산수율을 0에서 0.4 (g ethanol/g cellobiose)로 향상시켰다. 아울러 본 실험에서 개발한 돌연변이 균주는 cellobiose와 xylose 혼합당 조건에서 모균주에 비해 2배 가까이 향상된 ethanol 생산 및 생산속도를 나타내었다.