• Journal of Nutrition and Health
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• 제36권5호
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• pp.452-458
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• 2003

Soybean is a rich source of isoflavones such as genistein and daidzein. Soy isoflavones have both weak estrogenic and anti-estrogenic effects and are structurally similar to tamoxifen, an agent that has an effect similar to that of estrogen in terms of reducing postmenopausal bone loss. The purpose of this study was to determine the effects of differences in protein source (casein vs soy) and isoflavone levels (reduced vs higher levels) on selected bone markers and hormones in growing male rats. Thirty weanling Sprague-Dawley young rats were divided into 3 groups: The control group was fed a casein-based diet, the soy concentrate group was fed soy protein with totally reduced isoflavones content (isoflavones 0.07 mg/g protein), and the soy isolate group was fed soy protein with a higher than normal isoflavones content (isoflavones 3.4 mg/g protein). The degree of bone formation was estimated by measuring serum osteocalcin and alkaline phosphoatase (ALP). By determining collagen cross-linkage by immunoassay and correcting with creatinine values, the bone resorption rate was compared. Serum osteocalcin, growth hormone, estrogen and calcitonin were analyzed using radio immunoassay kits. The bone formation marker and ALP activity were differentiated by protein source, showing higher values than casein in feeding either soy isolate or soy concentrate. In this study using growing rats, the differences in isoflavone contents were not a significant factor in either bone formation or bone reaborption markers. Moreover, the soy isolate group had significantly higher levels of growth hormone than the casein group. The findings of this study suggest that growth hormone is partially responsible for its bone-formation effects in young growing rats. Soy protein and the isoflavones in soy protein are beneficial for bone-formation in growing male rats. Therefore, exposure to soy protein and isoflavones early in life may have long-term health benefits in preventing bone diseases such as osteoporosis. Further study to evaluate the mechanism of action of isoflavones on bones is warranted. (Korean J Nutrition 36(5): 452∼458, 2003)

• Parasites, Hosts and Diseases
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• 제37권4호
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• pp.277-283
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• 1999

To investigate the development of a subunit vaccine against theileriosis in cattle, the DNA fragments encoding piroplasm surface protein (p33) of Theileria sergenti of a Korean isolate were expressed in baculoviruses. The expressed p33 was characterized by indirect fluorescent antibody (IFA) and western blotting analysis. The expression of p33 was mainly detected on the surface of infected Sf21 cells by IFA. The immunoblotting analysis revealed the presence of a same molecular weight protein band of p33. The antigenicity of expressed polypeptide was further examined through the inoculation of a guinea pig. The sera of guinea pigs immunized with p33 expressed cell Iysate showed similar fluorescent antibody patterns and reacted with the same molecular weight protein of T. sergenti in immunoblotting analysis, thus indicating that this protein can be a promising candidate for a subunit vaccine in the future.

• 한국식생활문화학회지
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• 제14권5호
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• pp.477-485
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• 1999

This study was conducted to improve the functional properties of soybean protein isolate by dimethylglutarylation and acetylation. Amino acid composition and solubility of modified soybean protein by dimethylglutarylation were not changed, but lysine and trypsin inhibitor activity was decreased an isoelectric point was moved from pH5 to pH4 as a result of modification. Emulsification capacity and stability, foaming capacity and thermal stability were increased by the modification. In that 91% dimethylglutarylated protein did not coagulate when heating at $100^{\circ}C$ for 20 min. while its foaming stability was decreased. Whereas specific gravity was decreased by the modification of the soybean protein, relative viscosity and whiteness were improved. Generally, dimethylglutarylation produced more conformational changes in protein system than did in acetylation.

• 농약과학회지
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• 제14권4호
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• pp.446-455
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• 2010

주요 농업해충인 담배거세미나방에 대하여 높은 생물활성을 보이는 Bacillus thuringiensis subsp. kurstaki KB099 균주의 내독소단백질의 특성이 검토되었다. 이 균주의 내독소단백질은 효소 처리 없는 SDS-PAGE 결과 HD-l 균주에서는 일부 용해되어 130 kDa과 60 kDa의 두 개의 단백질밴드가 나타났으나 KB099균주에서는 용해되지 않고 130kDa의 밴드만이 관찰되었다. KB099균주의 내독소단백질에 감수성 해충인 담배거세미나방의 중장액으로 소화하였을 때에는 약 60 kDa 단백질밴드가 형성됨을 확인하였다. 또한 두 균주의 각각의 내독소단백질에 감수성해충의 소화액으로 반응시켰을 때 생물활성이 약했던 HD-l균주는 약6시간 만에 주요 밴드가 사라지는데 비해 활성이 강한 KB099균주는 12시간이상 까지도 활성밴드가 유지되다가 24시간 정도에서 밴드가 사라졌다. KB099균주가 생산하는 내독소단백질 유전자의 탐색을 위한 PCR실험에서 Cry1Aa, Cry1Ab, Cry1Ac, Cry1C, Cry1D 그리고 Cry1I 등 6개의 유전자가 존재함을 확인하였다.

• 한국식품과학회지
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• 제24권3호
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• pp.294-299
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• 1992

본 연구에서는 분리대두단백질에 단백질 가수분해효소를 처리하여 대두단백질에 가수분해적 변성을 야기하여 그 기능성을 변화 고찰하고 실제 식품에의 이용방법으로 효소처리된 두유로 두부를 만들어 물성실험과 관능평가를 실시하였다. 장엽에서 SPI를 제조한 후 15분간 bromelain으로 처리하여 2.7% 가수분해된 MSPI를 만들어 기능특성을 측정 비교하였다. MSPI는 전 pH범위에서 용해도가 증가하였고, 특히 등전점에서 15% 정도 증가하였다. 유화형성력과 기포팽창력은 증가하였으나 이들의 안정성은 감소하였는데, 특히 기포안정성은 알칼리쪽에서 급격히 감소하였고, 등전점에서는 가장 큰 것으로 나타났다. 표준두유와 변형두유를 혼합하여 제조한 두부로 물성실험과 관능평가를 실시하였을 때 압착실험에서는 변형두부I이 연하고 탄력성 있는 두부를 형성하는 것으로 나타났다. 각 두부의 물성모형은 spring 한개와 Maxwell 모형 세개를 가진 7요소모형으로 동일한 물성모형을 나타내었다. 관능평가에서는 표준두유와 변형두유를 3 : 1의 비율로 혼합하여 제조한 두부의 품질이 가장 우수한 것으로 평가되었다.

• 한국축산식품학회지
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• 제31권5호
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• pp.782-790
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• 2011

본 연구는 TGase 첨가에 따른 근원섬유 단백질과 비육류 단백질인 적소두단백질 또는 대두단백질간의 상호작용을 비교 평가하기 위해 수행되었다. 실험 1에서는 비육류 단백질 함량에 따른 물성 변화를 평가하였으며 실험 2에서는 TGase 반응시간에 따른 최적 조건을 평가하였다. 가열수율은 비육류 단백질을 첨가한 처리구에서 유의적으로 증가하였으며 특히 적소두단백질 1%을 첨가하였을 때 가장 높은 가열수율을 나타내었다(p<0.05). 반면에 겔 강도 및 점성도는 근원섬유 단백질 단독 처리구와 비육류 단백질을 첨가한 처리구와 비교하였을 때 유의적으로 차이가 나타나지 않았다(p>0.05). 또한 전기영동 결과는 가열 전 TGase 첨가 후 4시간 반응시켰을 때는 모든 처리구에서 변화를 보이지 않았지만(실험1), TGase 첨가 후 10시간 반응시킨 모든 처리구에서는 biopolymer 밴드가 나타났다(실험2). 또한 TGase 반응시간에 따른 겔 강도는 10시간째에 유의적으로 증가하였다(p<0.05). 하지만 10시간의 반응시간은 배양시간이 너무 길어 산업적으로 이용하기 부적합 하기 때문에 TGase함량을 0.5%로 증가시켜 효소와 단백질간의 최적 반응시간을 평가하고 비육류 단백질과의 상호작용을 통한 물성을 증진시키는 연구가 앞으로 필요할 것으로 사료된다.

• 한국축산식품학회지
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• 제35권6호
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• pp.841-846
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• 2015

This study was investigated to determine the effect of microbial transglutaminase (MTG) with or without red bean protein isolate (RBPI) on the porcine myofibrillar protein (MP) gel functionality at different pH values (pH 5.75-6.5). Cooking yield (CY, %), gel strength (GS, gf), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) were determined to measure gel characteristics. Since no differences were observed the interaction between 1% RBPI and pH, data were pooled. CY increased with the addition of 1% RBPI, while it was not affected by pH values. GS increased with increased pH and increased when 1% RBPI was added, regardless of pH. There were distinctive endothermic protein peaks, at 56.55 and 75.02℃ at pH 5.75, and 56.47 and 72.43℃ at pH 6.5 in DSC results, which revealed decreased temperature of the first peak with the addition of 1% RBPI and increased pH. In SEM, a more compact structure with fewer voids was shown with the addition of 1% RBPI and increased pH from 5.75 to 6.5. In addition, the three-dimensional structure was highly dense and hard at pH 6.5 when RBPI was added. These results indicated that the addition of 1% RBPI at pH 6.5 in MTG-mediated MP represent the optimum condition to attain maximum gel-formation and protein gel functionality.

• 한국식품과학회지
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• 제24권3호
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• pp.284-288
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• 1992

영양 저해인자로 알려진 phytate를 제거한 분리 유채단백(low-phytate rapeseed protein isolate)을 제조하여 유채단백질과 phytate와의 결합양상에 미치는 pH 및 phytate 첨가량의 영향을 알아보기 위하여 SDS-polyacrylamide gel 전기영동법을 수행하였다. 가용화된 분리 유채단백은 pH2.0과 pH5.0에서 phytate 첨가량이 증가할수록 가용성 단백질 band의 수가 감소하였으며 pH11.5에서는 band의 변화가 없었다. pH2.0에서 대조군의 18개 band중 7개의 band(105.8, 52.3, 37.3, 34.8, 26.3, 21.3, 18.4KDa)가 100 mg phytate 첨가시 침전되었으며 150 mg 첨가시에는 6개의 band(78.8, 46.5, 19.4, 16.8, 11.7, 8.5KDa)가 더 사라졌다. pH5.0에서는 대조군과 비교하여 15개의 band중 4개의 band(34.8, 21.3, 18.4, 16.8KDa)만이 phytate 첨가시 침전되었다. 따라서 유채단백을 식품소재로 이용하기 위해서는 phytate 함량을 낮춤으로써 그의 기능성을 향상시킬 수 있을 것이다.

• 한국식품과학회지
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• 제2권2호
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• pp.49-55
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• 1970

대두단백육(textured soybean protein food)의 제조 과정에서 분리한 대두단백의 건조공정은 단백 gel의 성질과 보수력, 점성도 같은 단백질 특성에 영향을 미쳤다. 모델시스템의 실험에서 질소용해계수로 표시한 대두단백의 변성도는 분리대두단백 gel의 강도의 중요한 변수로 나타났다. gel strength는 질소용해계수가 43이었을 때 최대가 되었고 질소 용해계수가 그보다 증가할 때나 감소할 때는 gel strength가 감소되었다. 이러한 사실은 분리대두단백의 건조공정 중 적당한 단백의 변성은 단백육제조에 필요하며 그 이상의 높은 질소용해계수를 갖도록 할 필요는 없다.

• Plant Biotechnology Reports
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• 제2권1호
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• pp.75-85
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• 2008

Prune dwarf virus (PDV) is an Ilarvirus systemically infecting almond trees and other Prunus species and spreading through pollen, among other means. We have studied strategies based on coat protein (cp) gene to block PDV replication in host plant cells. A Portuguese isolate of PDV was obtained from infected almond leaves and used to produce the cDNA of the cp gene. Various constructs were prepared based on this sequence, aiming for the transgenic expression of the original or modified PDV coat protein (cpPDVSense and cpPDVMutated) or for the expression of cpPDV RNA (cpPDVAntisense and cpPDVwithout start codon). All constructs were tested in a PDV host model, Nicotiana benthamiana, and extensive molecular characterization and controlled infections were performed on transformants and their progenies. Transgenic plants expressing the coat protein RNA were able to block the proliferation of a PDV isolate sharing only 91% homology with the isolate used for cpPDV cloning, as evaluated by DAS-ELISA on newly developed leaves. With cp expression, the blockage of PDV proliferation in newly developed leaves was only achieved with the construct cpPDV Mutated, where the coat protein has a substitution in the 14th aa residue, with arginine replaced by alanine. This result points to a possible role of the mutated amino acid in the virus ability to replicate and proliferate. This work reveals the possibility of achieving protection against PDV through either coat protein RNA or mutated cp sequence.