• 농업과학연구
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• 제45권3호
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• pp.485-492
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• 2018

Two experiments were conducted to investigate the effect of feeding a diet supplemented with swine hair protein (SHP) on the nutrient digestibility of Korean native chickens and their egg production as well as on egg quality. In experiment 1, twenty roosters of the Hanhyup-3 strain were assigned to an individual cage to give 10 replicates per treatment (i.e., 0 and 10% of SHP), and the nutrient digestibility in response to the SHP supplementation was measured. In experiment 2, fifty-four layers of the Hy-Line strain were assigned to an individual cage to give 27 replicates per treatment (i.e., 0 and 10% of SHP), and egg production and egg quality were measured. In experiment 1, no significant difference (p > 0.05) was found in the digestibility of crude protein, crude fat, nitrogen-free extract (NFE), and crude fiber in response to the diet supplemented with SHP. In experiment 2, although no significant difference (p > 0.05) was found with the dietary treatments, the 10% SHP supplemented diet decreased (p < 0.05) the feed intake of laying hens. However, the SHP supplemented diet did not affect (p > 0.05) the laying rate, egg weight and feed conversion ratio of those fed the diet. Eggshell thickness and yolk color decreased (p < 0.05); however, eggshell strength, eggshell color, albumen height and Haugh units increased (p < 0.05) by feeding layers a diet supplemented with SHP. In conclusion, the results suggest that 10% SHP supplemented in a poultry diet could be a useful protein source.

• 대한수의학회지
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• 제43권4호
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• pp.667-675
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• 2003

The safety of Brucella abortus strain RB51(SRB51) was investigated in dairy cows and Korean native cattle of 4~7th month of gestation. From experimentally inoculated cattle, 18 of 25 (72.0%) dairy cows, and 3 of 10 (30.0%) Korean native cattle were aborted or delivered premature fetus. There were no significant differences in the incidence of abortion depending on the inoculation route (intramuscular and subcutaneous) and dosages ($1{\times}10^9$, $2.8{\times}10^9$, and $4.0{\times}10^9$ CFU). The antibodies to the SRB51 were measured by a dot blot enzyme-linked immunosorbent assay. The highest titers to SRB51 were detected between 5~7 weeks after inoculation and the specitic antibody could be detected up to 28 weeks after inoculation. The SRB51 was isolated from amnio-allantoic fluid, bronchial lymph node, mammary gland, and supramammary lymph node in 5 of 25 dairy cows during 4 weeks after either abortion or delivery. Although SRB51 was isolated from 4 of 24 aborted fetus or normally delivered calves at parturition time, it was not isolated during 4 weeks afterward. Eleven of twentyfive dairy cows showed the endometritis and/or necrosis until 6 weeks after delivery, no lesions were seen at 8 weeks after delivery and uterus from control dairy cows. The results of present study revealed that SRB51 might induce the clinical signs of brucellosis in the pregnant cattle at 4~7th month of gestation.

• Journal of Microbiology and Biotechnology
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• 제28권10호
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• pp.1589-1603
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• 2018

Twenty analogs of $[Orn^6,D-Ala^9]{\alpha}-factor$ were synthesized and assayed for their biological activities: seven analogs of $[Orn^6,X^9]{\alpha}-factor$, seven analogs of $[X^6,D-Ala^9]{\alpha}-factor$, five analogs of $[X^5,X^6,D-Ala^9]{\alpha}-factor$, and native ${\alpha}-factor$ (X = amino acids). Their biological activities (halo, gene induction, and affinity) were measured using S. cerevisiae Y7925 and LM102 and compared with those of native ${\alpha}-factor$ (100%). G protein-coupled receptor was expressed in strain LM102 containing pESC-LEU-STE2 vector. $[Dap^6,D-Ala^9]{\alpha}-factor$ with weak halo activity (10%) showed the highest receptor affinity (> 230%) and the highest gene induction activity (167%). $[Arg^6,D-Ala^9]{\alpha}-factor$ showed the highest halo activity (2,000%). The number of active binding sites per cell (about 20,000 for strain LM102) was determined using a newly-designed fluorescence-based detector, $[Arg^6,D-Ala^9]{\alpha}-factor-Edan$, with high sensitivity (12,500-fold higher than the absorption-based detector $[Orn^6]{\alpha}-factor-[Cys]_3$).

• Journal of Microbiology
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• 제44권3호
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• pp.363-368
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• 2006

In this study, native Byadyrhizobium strains were isolated from the host plant, Glycine max, harvested from fields in Madhya Pradesh, India, and were typed by Iytic rhizobiophages. Eight indigenous (Soy2, ASR011, ASR031, ASR032, MSR091, ISR050, ISR076 and ISR078) and two exotic strains (USDA123 and CB1809), all of which evidenced a distinct reaction with six phages, were employed in this study. The symbiotic interaction of these strains was studied initially using soybean cultivar JS335 in a sand culture in a controlled environment, and the efficiency was assessed based on the nodule number, nodule dry weight, plant dry weight, nitrogenase activity, and total accumulation of N per plant. Symbiotic effectiveness was found to be highest with the native phage-sensitive isolate ASR011, whereas it was at a minimum with the phage-resistant isolates, ISR050 and ISR078. Additionally, the effectiveness of these strains was evaluated using six soybean cultivars belonging to different maturity groups; namely, Brags, Lee, Pusa20, PK416, JS33S and NRC37. Analysis of variance data evidenced significant differences due to both symbionts, for the majority of the tested parameters. The CB1809, USDA123, and ASR011 strains evidenced relatively superior symbiotic effectiveness with soybean cultivars Brags, Lee and JS335. Strain ISR078 evidenced no significant responses with any of the cultivars. The ASR031 strain performed moderately well with all tested cultivars. The symbiotic response of all the strains was quite poor with cultivar PK416. Our studies showed that a significant relationship existed between the phage sensitivity and symbiotic efficiency of the bacterial strains with the host-cultivars.

• Journal of Microbiology and Biotechnology
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• 제32권10호
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• pp.1325-1334
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• 2022

Global warming has accelerated in recent decades due to the continuous consumption of petroleum-based fuels. Cyanobacteria-derived biofuels are a promising carbon-neutral alternative to fossil fuels that may help achieve a cleaner environment. Here, we propose an effective strategy based on the large-scale cultivation of a newly isolated cyanobacterial strain to produce phycobiliprotein and biodiesel, thus demonstrating the potential commercial applicability of the isolated microalgal strain. A native cyanobacterium was isolated from Goryeong, Korea, and identified as Pseudanabaena mucicola GO0704 through 16s RNA analysis. The potential exploitation of P. mucicola GO0704 was explored by analyzing several parameters for mixotrophic culture, and optimal growth was achieved through the addition of sodium acetate (1 g/l) to the BG-11 medium. Next, the cultures were scaled up to a stirred-tank bioreactor in mixotrophic conditions to maximize the productivity of biomass and metabolites. The biomass, phycobiliprotein, and fatty acids concentrations in sodium acetate-treated cells were enhanced, and the highest biodiesel productivity (8.1 mg/l/d) was achieved at 96 h. Finally, the properties of the fuel derived from P. mucicola GO0704 were estimated with converted biodiesels according to the composition of fatty acids. Most of the characteristics of the final product, except for the cloud point, were compliant with international biodiesel standards [ASTM 6761 (US) and EN 14214 (Europe)].

• 한국작물학회지
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• 제39권5호
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• pp.453-457
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• 1994

본 시험은 1990년 11월부터 1992년 11월까지 국내에서 수집된 시호 6계통과 일본에서 도입된 삼도종을 공시하여 생육특성, 근수양성 및 saikosaponin 함량을 조사한 것으로 그 결과를 요약하면 다음과 같다. 1. 재래종 시호의 개화기는 1년생이 8월 2∼3일, 2년생은 7월 16∼18일로, 1년생보다 2년생이 일찍 개화하였으며, 일본도입종인 삼도종은 국내 수집종에 비하여 1년생은 18일, 2년생은 32일각각 늦게 개화하였다. 2. 초장 및 경태에서 춘천종은 초장이 크고 경태가 굵은 편이었으며 삼도종은 다분지형이었다. 3. 근장, 근태 및 지근수는 국내 수집종간에는 큰 차이가 없었으나 삼도종은 뿌리가 굵고 짧으며 지근이 적은 경향이었고, 건근수량은 1, 2년생모두 춘천종이 높았으며, 2년생근의 10a당 평균수량은 105Kg으로 1년생근에 비해 2.6배를 보였다. 4. Saikosaponin 함량면에서 춘천종은 1, 2년생근 모두에서 높은 편이었고, saikosaponin 조성에서는 국내 재래종이 일본에서 도입된 삼도종보다 약리활성이 높은 saikosaponin a 및 d의 함량비율이 높아 품질이 우수한 것으로 나타났다.

• 한국가금학회지
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• 제51권2호
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• pp.83-95
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• 2024

본 연구는 산란능력이 우수한 토종 산란용 실용계를 개발하기 위해 선정된 국내 토종닭 종계(YC, YD, CK, CF) 4계통을 대상으로 2원 교배를 실시하였다. 능력검정은 12개 조합의 287수를 대상으로 18주령부터 64주령까지 체중, 생존율, 초산일령, 시산일령, 산란율, 계란 품질 및 난형을 조사하였다. 분석 결과, 체중은 YCYD, YDYC 조합이 가장 무거웠으며 생존율은 CKYC, YDYC 조합이 64주령까지 94% 이상의 생존율을 보였다. 시산일령은 CFYC 조합이 127일, 초산일령은 YDCF 조합이 140일로 각각 해당하는 종계들의 성적보다 시산일령과 초산일령이 모두 빨랐다. 산란율은 52주령 이후로 대부분의 조합들이 산란율이 떨어지는양상을 보였지만 YDCF 조합은 60주령까지 70% 이상의 산란지속성을 나타내며 가장 우수한 산란율 보였다. 계란품질에서 난중은 CKCF, YCCF가 가장 무거웠고, 난각색은 토종닭 대부분의 조합들이 Hy-Line Brown에 비해 유의적으로 밝게 나타난 반면 조합들 중에서는 YCYD 및 YDYC 조합이가장 짙은 색을 나타냈다. 난각 두께는 토종닭 조합 중 YCCF 조합이 두꺼웠으며 난각 강도는 CKYC 조합이 가장 강했다. 토종닭의 난형은 CKCF 조합이 Hy-Line Brown에 비해 장축이 유의적으로 길게 나타났으며 세로가 길쭉한 모양을 나타내었다. 토종닭 교배조합들의 난황색은 Y계통이 들어간 조합에서 짙은색을 나타냈으며 난황비율또한 Hy-Line Brown에 비해 유의적으로 높았다. 종합하자면 실용계들의 능력검정을 통해 최적의 토종 산란용 실용계를 선정시 산란율이 우수한 YDCF, 계란품질이 우수하면서 상대적으로 산란율이 양호했던 YCCF 조합이 가장 바람직한 조합으로 판단된다. 또한, 추후에는 난형지수에 관한 고려 및 교배조합들의 능력을 최대로 발현하기 위한 영양소 요구량 등의 연구가 필요하다고 사료된다. 이에 지속적으로 토종닭 산란계의 계란 생산성 관련 연구를 진행하여 토종닭 계란 등급제를 확립하고 품질과 맛을 개선한다면 토종닭 산란계 농가의 소득을 향상시키고 소비자에게 프리미엄 식재료를 공급할수 있을 것으로 판단된다.

• 농약과학회지
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• 제13권4호
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• pp.262-266
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• 2009

유채 근권으로 부터 분리된 고활성 근권균 Burkholderia pyrrocinia 13-1는 유채의 생육을 촉진 시키며 특히 저온조건에서의 식물 생육이 우수하다. 이 균주의 유채 처리는 저온조건에서 뿌리의 발근을 좋게 하며 지상부 생육도 다른 대조 균주처리 보다 우수하다. 근권미생물이 가지는 유용 기능 중 식물의 영양 흡수와 병 저항성에 관여하는 시드로포어의 생성, 항균활성과 토양 중 불용화 인산인 칼슘포스페이트를 가용화시켜 식물의 흡수를 돕는 용해 능력이 우수하였다. 이와 같은 특성은 식물의 생육을 촉진시키는 근권세균의 활성기작으로 식물생육 촉진용으로 유채재배에 적용할 수 있을 것으로 기대된다.

• Journal of Microbiology and Biotechnology
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• 제34권3호
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• pp.700-709
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• 2024

Polyhydroxybutyrate (PHB) production from lignocellulosic biomass is economically beneficial. Because lignocellulosic biomass is a mixture rich in glucose and xylose, Escherichia coli, which prefers glucose, needs to overcome glucose repression for efficient biosugar use. To avoid glucose repression, here, we overexpressed a xylose regulator (xylR) in an E. coli strain expressing bktB, phaB, and phaC from Cupriavidus necator and evaluated the effect of xylR on PHB production. XylR overexpression increased xylose consumption from 0% to 46.53% and produced 4.45-fold more PHB than the control strain without xylR in a 1% sugar mixture of glucose and xylose (1:1). When the xylR-overexpressed strain was applied to sugars from lignocellulosic biomass, cell growth and PHB production of the strain showed a 4.7-fold increase from the control strain, yielding 2.58 ± 0.02 g/l PHB and 4.43 ± 0.28 g/l dry cell weight in a 1% hydrolysate mixture. XylR overexpression increased the expression of xylose operon genes by up to 1.7-fold. Moreover, the effect of xylR was substantially different in various E. coli strains. Overall, the results showed the effect of xylR overexpression on PHB production in a non-native PHB producer and the possible application of xylR for xylose utilization in E. coli.

• Journal of Microbiology
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• 제34권2호
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• pp.151-157
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• 1996

By PCR amplification using the sequence of the previously cloned shiga-like toxin II DNA, a gene encoding it has been cloned from an isolate of healthy Korean native bovine feces, Escherichia coli KSC109. The nucleotide sequence s included tow open reading frames coding for 319 and 89 amino acids corresponding to A and B subunits, respectively. Comparison of the nucleotide and predicted amino acid sequences of newly cloned gene (slt-II) with those of others in the SLT-II family revealed completely identical homology with SLT-II cloned previously from bacteriophabe DNA of E. coli 933 derived from a patient with hemorrhagic colities. In addition, the sequence homology of SLT-II with SLT-II variant form bovine was more than 95% at both the nucleotide and protein levels. Overexpression of SLT-II recombinant gene by induction with IPTG using an E, coli hostvector, system was conducted and the correctly processed products with active mature form exhibited 1000-fold higher cytotoxycity for Vero cells than that form original strain.