• 한국동물위생학회지
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• 제20권3호
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• pp.313-321
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• 1997

The antibiotic residues of the urine, the liver, the lung, the kidney and the spleen in slaughtered pigs at Kyongbuk province were detected by TLC(505 kit) and EEC-4 plate method. 1. The positive rate of residual sulfamethazine which was detected by 505 kit in the urine (n=200) was 0.0%. 2. The positive rate of residual sulfamethazine which was detected by EEC-4 plate in the urine (n=126), the liver(n=98), the kidney(n=72), the spleen (n=68) and the lung(n=48) were 63%, 49%, 36%, 34% and 24%, respectively. 3. By EEC-4 plate method, the positive detection rates of the urine were 53.0% in BS(pH 6.0), 29.0% in BS(pH 7.2), 11.5% in BS(pH 8.0) and 13.0% in ML(pH 8.0) medium, that of the liver 41.5% in BS(pH 6.0), 22.0% in BS(pH 7.2), 6.5% in BS(pH 8.0) and 5.0%, in ML (pH 8.0) medium, that of the lung 21.0% in BS(pH 6.0), 9.5%, in BS(pH 7.2) and 8.5% in BS(pH 8.0) medium, and that of the kidney 31.5% in BS(pH 6.0), 14.5% in BS(pH 7.2), 20.0% in BS(pH 8.0) and 3.0% in ML(pH 8.0) medium. In the spleen, only in BS(pH 6.0) medium the positive rate was detected as 33.5 %. 4. The positive rates of samples which shown TLC-positive detected by EEC-4 plate method were 53.9% in no band, 77.8% in one band, 80.9% in two bands, 66.7% in three bands, respectively. In conclusion, the EEC-4 plate method could be applied for the detection of residual antibiotics in samples which shown as out of standard Rf values by TLC-method (SOS kit).

• 한국축산식품학회지
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• 제30권1호
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• pp.154-162
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• 2010

This study was carried out to compare the efficacy and selectivity of TOS and BS media for enumeration of bifidobacteria in commercial fermented milk products. First, bifidobacteria was isolated from 20 fermented milk products, and all isolated bifidobacteria were identified by genomic technology as Bifidobacterium lactis. The two media significantly differed from each other with regard to the recovery of B. lactis, that is, the recovery of this organism was as much as 6 logs lower on BS medium than on TOS. When the concentration of BS solution (mixture of paromomycin sulfate, neomycin, sodium propionate, and lithium chloride) used in BS medium was reduced to 50% (BS50), a relatively high percentage recovery of bifidobacteria from pure cultures was achieved. Susceptibility tests to antibiotics and tests for selective agents for the isolated bifidobacteria and lactic acid bacteria were conducted. The BS solution inhibited some lactic acid bacteria and Bifidobacterium species, while mupirocin (MU) suppressed the growth of all tested lactic acid bacteria but not Bifidobacterium. As compared with BS50 medium, TOS with or without MU showed good bifidobacteria recovery and readily distinguishable colonies; in particular, TOS supplemented with MU had a high selectivity for bifidobacteria. In conclusion, all results suggested that TOS medium with or without MU was found to be suitable for selective enumeration of bifidobacteria from mixed cultures in fermented milk, and better in that capacity than BS medium.

• 한국식품과학회지
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• 제26권5호
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• pp.526-531
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• 1994

한국인의 장내 균총 조사를 하던 중 Bifidobacterium 선택배지로 개발된 Mitsuoka의 BS배지에서 상당수의 Bifidobacterium이 사멸되는 것으로 나타났다. 이에 보다 개량된 Bifidobacterium의 선택배지를 조제하기 위하여 한국인들로부터 Bifidobacterium들을 비선택 배지및 기존의 선택배지에서 분리한 뒤 동정하였다. 분리 동정된 균주들에 대하여 항생제와 대사저해제에 대한 감수성 조사 및 특이 기질검사를 하여 선택배지 조제의 기초 자료로 활용하여 Bifidobacterium이 선택적으로 자랄 수 있는 배지로 TP배지를 고안하였다 TP배지는 상용되는 Mitsuoka의 BS배지보다 Bifidobacterium 선택성이 우수하였고 colony 성장속도도 빨랐다.

• Journal of Microbiology and Biotechnology
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• 제34권8호
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• pp.1671-1679
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• 2024

Aspergillus flavus, the primary mold that causes food spoilage, poses significant health and economic problems worldwide. Eliminating A. flavus growth is essential to ensure the safety of agricultural products, and extracellular compounds (ECCs) produced by Bacillus spp. have been demonstrated to inhibit the growth of this pathogen. In this study, we aimed to identify microorganisms efficient at inhibiting A. flavus growth and degrading aflatoxin B₁. We isolated microorganisms from soil samples using a culture medium containing coumarin (CM medium) as the sole carbon source. Of the 498 isolates grown on CM medium, only 132 bacterial strains were capable of inhibiting A. flavus growth. Isolate 3BS12-4, identified as Bacillus siamensis, exhibited the highest antifungal activity with an inhibition ratio of 43.10%, and was therefore selected for further studies. The inhibition of A. flavus by isolate 3BS12-4 was predominantly attributed to ECCs, with a minimum inhibitory concentration and minimum fungicidal concentration of 0.512 g/ml. SEM analysis revealed that the ECCs disrupted the mycelium of A. flavus. The hydrolytic enzyme activity of the ECCs was assessed by protease, β-1,3-glucanase, and chitinase activity. Our results demonstrate a remarkable 96.11% aflatoxin B1 degradation mediated by ECCs produced by isolate 3BS12-4. Furthermore, treatment with these compounds resulted in a significant 97.93% inhibition of A. flavus growth on peanut seeds. These findings collectively present B. siamensis 3BS12-4 as a promising tool for developing environmentally friendly products to manage aflatoxin-producing fungi and contribute to the enhancement of agricultural product safety and food security.

• Journal of Communications and Networks
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• 제17권3호
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• pp.247-255
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• 2015

In this paper, we propose an adaptive time division multiple access based medium access control (MAC) protocol, called bitmap-assisted shortest job first based MAC (BS-MAC), for hierarchical wireless sensor networks (WSNs). The main contribution of BS-MAC is that: (a) It uses small size time slots. (b) The number of those time slots is more than the number of member nodes. (c) Shortest job first (SJF) algorithm to schedule time slots. (d) Short node address (1 byte) to identify members nodes. First two contributions of BS-MAC handle adaptive traffic loads of all members in an efficient manner. The SJF algorithm reduces node's job completion time and to minimize the average packet delay of nodes. The short node address reduces the control overhead and makes the proposed scheme an energy efficient. The simulation results verify that the proposed BS-MAC transmits more data with less delay and energy consumption compared to the existing MAC protocols.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.393-397
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• 2003

P. aeruginosa F722는 탄화수소를 분해하는 과정에 biosurfactant (BS)를 생산한다. 탄화수소 분해에 사용되는 C-배지에서 BS 생산량은 0.78 $g/{\ell}$ 이였나, 질소원과 탄소원을 각각 0.05% (w/v) $NH_4Cl\;+\;0.1%$ (w/v) yeast extract과 3.0% (w/v) glucose로 조정한 경우는 BS 생산량이 1.66 $g/{\ell}$로 증가하였다. 최적의 BS 생산조건으로 배양하는 동안 air 1.0 LPM를 공급해 주었을 때는 공기를 공급하지 않을 때의 1.66 $g/{\ell}$보다 약 20% 증가한 1.94 $g/{\ell}$이였다. 뿐만 아니라, glucose 분해속도는 대수증식기와 정지기에서 air를 공급하지 않은 경우0.25, 0.18 $h^{-1}$였으나, 1.0 LPM를 공급한 경우 0.33, 0.29 $h^{-1}$로 조사되었다. 또한, air를 공급하면서 BS 생산 실험을 수행하였을 때, BS 활성이 더 안정적이었다.

• Journal of Microbiology and Biotechnology
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• 제21권7호
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• pp.679-685
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• 2011

Xanthomonas oryzae pv. oryzae (Xoo) produces a putative effector, XoAvrBs2. We expressed XoAvrBs2 homologously in Xoo with a TAP-tag at the C-terminus to enable quantitative analysis of protein expression and secretion. Addition of rice leaf extracts from both Xoo-sensitive and Xoo-resistant rice cultivars to the Xoo cells induced expression of the XoAvrBs2 gene at the transcriptional and translational levels, and also stimulated a remarkable amount of XoAvrBs2 secretion into the medium. In a T3SS-defective Xoo mutant strain, secretion of the TAPtagged XoAvrBs2 was blocked. Thus, we elucidated the transcriptional and translational expressions of the XoAvrBs2 gene in Xoo was induced in vitro by the interaction with rice and the induced secretion of XoAvrBs2 was T3SSdependent. It is the first report to measure the homologous expression and secretion of XoAvrBs2 in vitro by rice leaf extract. Our system for the quantitative analysis of effector protein expression and secretion could be generally used for the study of host-pathogen interactions.

• 한국미생물·생명공학회지
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• 제21권1호
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• pp.82-87
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• 1993

한국 전통 발효식품의 숙성에 절대 혐기성 세균이 관여하는지를 보기 위해 김치류와 장류 14종의 시료를 복합 BL 배지 혹은 bifidus 세균 선택 배지인 BS agar에 접종하여 절대 혐기적으로 배양한 결과 복합 BL 배지에서 $10^7$ ~ $10^8$/g 시료의 세균이 생장하였으며, BS agar에서는 $10^3$ ~ $10^6$/g 시료의 colony가 형성되었다. 이들은 모두 호기성 조건에서도 생장 할 수 잇었으며, BS 배지에서 생장하는 세균은 fructose-6-phosphate phosphoketolase를 합성하지 않는 것으로 나타났다. 또한 표준 Bifidobacterium속 세균은 3% NaCl을 함유하는 배지에서는 생장할 수 없었다. 이상의 결과로부터 김치류와 장류 등 염 농도가 높은 발표식품에는 bifidus균은 생장할 수 없다고 판단된다.

• 한국미생물·생명공학회지
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• 제26권4호
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• pp.369-372
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• 1998

Microbial insecticide formulations were prepared by liquid and semi-solid fermentations using Bacillus thuringiensis subsp. kurstaki, HL-106 (BTK-HL106), B. thuringiensis subsp. israelensis HL-63 (BTI-HL63) and B. sphaericus 1593 (BS-1593) strains. The liquid fermentation medium contained molasses 2%, dextrose 1.5%, peptone 2%, D-xylose 0.025%, CaCl$_2$ 0.1%, K$_2$HPO$_4$ 0.1%, KH$_2$PO$_4$ 0.1%, MgSO$_4$$.$7H$_2$O 0.03%, FeSO$_4$$.$7H$_2$O 0.002%, ZnSO$_4$$.$7H$_2$O 0.02%. The composition of the semi-solid fermentation medium was rice bran 45.2%, zeolite 31%, yeast powder 0.02%, corn powder 5%, dextrose 3%, lime 0.3%, NaCl 0.06%, CaCl$_2$ 0.02%, and H$_2$O 15.42%. Insecticide formulations produced in the liquid fermentation named BTK-HL106, BTI-HL63 and BS-1593 pesticides and those in the semi-solid fermentation were designated as BTK-HL106-1, BTI-HL63-1 and BS-1593-1 pesticides, respectively. The number of spore (endotoxin crystals) was 2.65${\times}$10$\^$9/ spores per $m\ell$ in the BTK-HL106 and 3.5${\times}$10$\^$10/ in the BTK-HL106-1 3.8${\times}$10$\^$9/ spores in the BTI-HL63 and 7.0${\times}$10$\^$10/ in the BTI-HL63-1, and 7.5${\times}$10$\^$9/ in the BS-1593 and 1.4${\times}$10$\^$10/ in the BS-1593-1. The spores in the BS-1593 formulation was produced two times more than the other formulations. The spores in the BTI-HL63-1 were contained twice than those in the BTK-HL106-1, and five times than those in the BS-1593-1. The results indicated that spore (endotoxin crystals) productions in the semi-solid fermentation increased about ten times than those in the liquid fermentations. $LC_{50}$s of the BTI-HL63 and BS-1593 were 4.5 $\mu\textrm{g}$, and those of the BTI-HL63-1 and BS-1593-1 were 1.5 $\mu\textrm{g}$. $LC_{50}$ of the BTK-HL106 was 1.5 mg and that of the BTK-HL106-1 was 0.9 mg. The $LC_{50}$s of the formulations in the semi-solid fermentations showed about two to three times higher than those in the liquid fermentations.

• 한국토양비료학회지
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• 제49권5호
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• pp.621-626
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• 2016

The present study evaluated the variations in soil microbial population of controlled horticultural land used for lettuce (Lactuca sativa) cultivation by their fatty acid methyl ester and chemical properties. We utilized four treatment groups, no treatment (NT), culture medium (CM), Bacillus subtilis S37-2 (KACC 91281P) ${\times}10^6CFU\;mL^{-1}$ (BS1), and Bacillus subtilis $S37-2{\times}10^7CFU\;mL^{-1}$ (BS2) and analyzed these variations throughout the before treatment and harvesting stage. The chemical properties such as pH, organic matter, available phosphate, and electrical conductivity in soils before treatment and harvesting stage showed no significant difference among the treatments. Total numbers of bacteria and microbial biomass C in soil treated with BS1 were larger than those of NT, CM, and BS2, whereas total number of fungi at the harvesting stage was significantly lower in the BS1 soil than in the NT and CM soils (P < 0.05). On basis of leaf length, leaf width, leaf number and leaf weight, the growth characteristics lettuce on the soil treated with BS1 and BS2 was faster than those of NT and CM soils. Yield of lettuce with treated BS1 and BS2 were 35% and 29% more than that of NT, respectively.