• Korean Journal of Food Science and Technology
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• v.5 no.4
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• pp.210-214
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• 1973

This study analyses and compares the amino acid composition and available lysine content between Korean fermented soybean Meju and its products as well as home-made and commercially made products. The protein quality of the products was evaluated by the result, and the biological value of the proteins was estimated by using the regression equation for chemical score to biological value as calculated by B.O. Eggum. The amino-N content of soybean is found to be 85% of the total nitrogen content and is reduced to approximately 75% in the fermented products except home-made soysauce, where as the content of ammonia-N and other N-compounds is increased. The difference in protein quality between home-made and commercially made products is not found to be significant. The protein quality of soybean is not damaged greatly in the making of Meju but is seriously damaged during the long periods of ripening. After the ripening the chemical score of the products' protein is reduced to approximately one half of the original soybean protein and the available lysine content to $1/3{\sim}1/2$.

• Plant Resources
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• v.1 no.2
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• pp.113-120
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• 1998

Soybean is an important crop because its seed has very high protein relative to others. The quality of soy protein is limited by the concentration of the sulfur-containing amino acids in the amino acid profile. Among the supply of various forms of 0.4mM sulfur as S nutrition during seed fill. only 0.4mM L-methionine can inhibit ${\beta}$-subunit synthesis completely and produce the highest glycinin-containing seeds. Compared to 0.4mM sulfate control, seeds supplied by 0.4mM L-methionine have lower ${\alpha}$-, no ${\beta}$-subunit, and highly increased glycinin without altering total protein concentration. Supply of 0.2mM cystine (0.4mM S) did not affect the accumulative pattern of seed storage protein (SSP) subunits. In the supply of L-methionine, 0.2mM treatment showed higher glycinin in seeds but 0.05mM resulted in lower glycinin than tile sulfate control. The relative abundance of ${\alpha}^`$-subunit was not altered by any N or S nutrition. Under 5mM nitrogen, protein concentration was increased about 3-5% by substituting ammonia for nitrate during seed fill independent of nutrition. The increase resulted in the only increase of 7S protein, mainly ${\beta}$-subunit. Our data suggest that the regulatory system of SSP genes responds to the balance between N and S assimilates supplied from mother plant. and controls the di fferential synthesis of their subunits for the maximum protein accumulation in developing soybean seed.

• Korean journal of food and cookery science
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• v.9 no.4
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• pp.308-311
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• 1993

This study was carried out in order to study the effect of mungbean protein on quality characteristics of angel parfait. The foaming properties of mungbean protein was tested and angel parfait was made with mungbean protein. The results were as follows: 1. Foam expansion values of mungbean protein were generally dependent on protein concentration to 3かio protein suspension. From 1％ to 3％ suspen-sion, foam expansion values increased. However, over 3％ suspension, the values decreased. 2. The foaming stability appeared the greatest value as protein concentration increased. But it was not signifi-cantly different over than 5% concentration. 3. The overrun of angel parfait made with munbean protein was significantly higher than that of made with soybean protein and sensory evaluation data presented that angel parfait made with mungbean protein was significantly higher than that of soybean protein.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.1
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• pp.33-40
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• 2015

Soybean is very useful crop to supply vegetable protein for human. Supply of soybean is increased because it has useful ingredient. Recently, cultivation of soybean in paddy field is increasing due to the increase of rice stockpile in Korea. Hence, in this study, expression of protein was identified regarding different environment for cultivation to investigate the effect of different environment on protein expression. Two-dimensional electrophoresis was performed to investigate the expression of protein using image analysis program to measure degree of protein expression in numerical value. Hannam-kong, Beakcheon-Kong, Hwangkeum-Kong, and Danwon-Kong were used as plant material. 2-DE combined with image analysis revealed that each degree of protein expression of Hannam-Kong and Hwangkeum-Kong in upland field was higher than degree of protein expression in paddy field. However, in case of Beackcheon-Kong, the phenomenon was opposite. In Danwon-kong, the degree of protein expression was not different between up-land field and paddy field. To this end, major protein spots were not different between paddy field and upland field among all cultivars. It could be suggested that protein expression is not severely different by various environment, but different environment affects degree of protein expression.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.1
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• pp.114-122
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• 2015

Soybean is very useful crop to supply vegetable protein for human. However, cultivation arear of this economically important crop is gradually diminished in upland field. Hence, cultivation area of soybean is increased in paddy field. During the growth duration of soybean, excessive moisture injury is serious problem for sustainable production and supply. We investigated protein expression according to different period of seed soaking and germination after seed soaking. For comparison on expression of protein according to different condition, we performed two-dimensional electrophoresis. After electrophoresis analysis, we selected differentially expressed protein spots according to different condition such as soaking period and germination after soaking to identify protein function by using MALDI-TOF. Results revealed that pattern of expression of protein according to soaking period and germination after soaking were generally not different in major spots. However, degree of expression of protein in some protein spots was increased in accordance with decrease of soaking period. Especially, in Hwangkeum-Kong, Danyeop-Kon, and Pecking, the degree of expression of protein was remarkably increased for 4 days after soaking. But, according to germination after soaking, degree of expression of protein in germinated seeds of all cultivars was higher than un-germinated seeds. In results of MALDI-TOF analysis, specific proteins were identified by different soaking period such as Allergen Gly m Bd 28K, P24 oleosin isoform B. Also, in accordance with germination, degree of protein expression of the related protein, Gibberellin was increased in un-germinated seeds of Iksan-Kong. In ungerminated seeds of Sinpaldal-kong, proteins were identified as down-regulated by soaking such as ATP binding and Inhibitor II', proteinase.

• The Korean Journal of Food And Nutrition
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• v.32 no.6
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• pp.643-650
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• 2019

The purpose of this study was to investigate the quality of dehulled soybean (DHSB), and the rapid preparation possibility of soybean milk with DHSB (SM-DHSB), and then the quality of SM-DHSB. In DHSB, the moisture content decreased, the crude protein, crude fat, minerals, and carbohydrate contents increased, and the isoflavone (daidzein, genistein and glycitein) content was similar to that of soybean (SB). The water absorption rate of DHSB for soybean milk preparation was higher than that of SB. In the results of SM-DHSB and soybean milk (SM) qualities, the crude protein content, total solid content, and the viscosity of SM-DHSB were higher, the yield and the proximate composition (except crude protein) were similar, and the Biji production rate, and total dietary fiber content of SM-DHSB were lower compared to the SM. In terms of the isoflavone contents of SM-DHSB, daidzein and genistein content were similar, and glycitein content was lower compared with the SM. Consequently, these results suggest the possible use of DHSB for rapid SM-DHSB preparation, because the soaking time was decreased by the high water absorption rate of DHSB in the SM preparation, and the quality of SM-DHSB improved compared to those of the SM.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.1
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• pp.115-122
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• 1993

A study was conducted to compare the effect of feeding commercial formula ration and corn-soybean meal based rations on growth performance, feed conversion ratio, mortality percentage, dressing percentage, carcass composition and economics of raising broiler chicks at commercial farms. 3000 day old broiler chicks were randomly divided into 4 groups with 3 replicates of 250 birds in each. Four iso-nitrogenous and isocaloric rations (A, B, C and D) were prepared and randomly allotted to each group. Ration A was a commercial broiler ration whereas ration B had the same formula with the exception that all the animal protein sources were replaced with soybean meal (SBM). Ration C was based on only corn and SBM. Ration D contained corn, SBM and 25% fullfat soybean (FFSB). The birds were given the experimental rations starter from day 1 to 28 and finisher from 29 to 49. The results indicated that the birds fed on corn-soybean meal based rations gained significantly figher weights showed better feed conversion ratio, gave higher dressing percentage with better carcass composition, lower mortality and higher net profits as compared to those fed on commercial ration. The replacement of animal protein sources in commercial ration with SBM (ration B) although did not show any significant differences in the performance of birds as compared to ration A, a little improvement was visible indicating that SBM can be used as a good substitute of animal protein sources. Similarly the replacement of SBM with FFSB up to a level of 25% did not affect the broiler performance as compared to only SBM.

• Proceedings of the Botanical Society of Korea Conference
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• 1987.07a
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• pp.283-307
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• 1987

Glycinin and $\beta$-conglycinin are the most abundant storage protein in soybean. These proteins are known to be synthesized predominantly during germination and cell expansion phase of seed development for short period, and synthesized not in other tissues. Genes encoding these storage proteins are useful system to study the mechanism of development stage and tissue specific gene expression in eukaryotes, especially plants, at the molecular level. The cDNA and genomic clones coding for glycinin have been isolated and regulation mechanism of the gene expression has been studied. Initially, development and tissue-specific expression of the glycinin gene is regulated at the level of transcription. Post-transcriptional processing is also responsible for delayed accumulation of the mRNA. Translational control of the storage protein gene has not been reported. Post-translational modification is another strategic point to regulate the expression of the gene. It is possible to identify positive and/or negative reguratory clements in vivo by producing transgenic plants agter gene manipulation. Elucidation of activation and repression mechanism of soybean storage protein genes will contribute to the understanding of the other plant and eukaryotic genes at molecular level.

• Proceedings of the Botanical Society of Korea Conference
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• 2002.04a
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• pp.106-106
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• 2002

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47
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• pp.95-106
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• 2002

Soybean is one of the most important sources of protein and oil in the world. Recently, emphasis has been laid on the chemical composition of soybean seeds for the processing soybean foods. Improvement of soybean components has been expected to improve food-processing quality for the processed soybean products such as soymilk and various edible ingredients as well as fur the traditional soyfoods. In Korea, soybean breeding research programmes have been focused on the quality of the products derived from soybean with yield stability, and some new modified soybean varieties haying good food-processing quality were developed recently. So the efforts of establishing standard and standardization of products in soybean are important. Three main categories should be considered in view of soybean seed quality; the marketing value such as grain size, shape, and appearance; the eating and processing value such as dehulled ratio, water absorption rate, and benny flavor; the nutritional value such as protein, lipid, and carbohydrate contents. And the new frontiers in research are looking at the functional nutrients in soybeans and how to improve them. In case marketing value, mainly the appearance is evaluated, therefore, each country has an application of standard related to quality. Each determination of standard class, heat-damaged kernels, splits, and soybeans of other colors is made on the basis of the grain when free from foreign materials. But processing value and nutritional value for standardization were not studied in detail till now. In addition, soybean has potential roles in the prevention and treatment of chronic diseases, most notably cancer, osteoporosis, and heart disease. The functional nutrients include a protease inhibitor, phytic acid, saponins, and isoflavones, etc.. It is believed that standardization of soybean quality should perform to overcome the difficulties, relatively high price of domestic soybean products has weakened the competitive power, in the market related to WTO. So, we should focus on further research into the evaluation and establishment of quality-standard in soybean.