• Korean Journal of Food Science and Technology
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• v.3 no.2
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• pp.101-104
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• 1971

The dye-binding method based on the reaction of acidic orange-G dye with basic groups of protein molecule was investigated to observe its applicability to the determination of protein, basic amino acid and lysine contents in brown rice of several high-protein rice lines. The protein content of rice samples ranged from 7.91 to 10.53% and from 8.93 to 11.96% in terms of wet and dry bases, respectively. The correlation between dye-binding absorbance and protein content in terms of both dry and wet bases was highly significant; their correlation coefficients being $-0.955^{**}\;and\;-0.975^{**}$, respectively. The correlation of dye-binding absorbance lysine and basic amino acids were highly significant and their correlation coefficients were similar. Dye-binding absorbance-lysine showed a lower correlation than dye-binding absorbance-protein but a higher correlation than protein-lysine.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.66-71
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• 2008

A total of 284 milled rice (MR) marketed in Korea were analyzed for grading characteristics (head rice, broken kernels, chalky kernels, and damaged kernels%), color characteristics (L-, a-, b-values, and whiteness), protein content (%), and the cooked rice (CR) sensory quality to investigate the key characteristics affecting the overall sensory quality of rice marketed in Korea. Relatively high correlation with the overall sensory quality of the CR was found in color characteristics such b-value of the CR (r=-0.779) and MR (r=-0.545), the a-value of the CR (r=0.513), and the whiteness (r=0.298) of the MR, compared to protein (r=-0.150), and the moisture (r=0.158) contents of the MR and the percentage of head rice (r=0.195). Partial least squares (PLS) regression of the CR b-value with various characteristics of the MR showed that CR b-value was increased with MR b-value effectively, followed by protein content, damaged kernels, chalky kernels, and colored kernels of MR while it was decreased with whiteness and moisture content for the MR.

• Applied Biological Chemistry
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• v.32 no.1
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• pp.64-72
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• 1989

Near full length cDNA clones encoding the rice seed storage protein, prolamine, were isolated and divided into two homology classes based on cross-hybridization and DNA sequencing analysis. These cDNA clones contain a single open reading frame encoding a putative rice prolamine precursor(M.W.=17,200) possessing atypical 14 amino acid signal peptide. Clones of these two homology classes diverge mainly by insertions/deletions of short nucleotide stretches and point mutations. The deduced primary structures of both types of prolamine polypeptides are devoid of any major tandem repetitive sequences, a feature prevalent in other cereal prolamines. No significant homology teas detected between the rice prolamine and other cereal prolamines, indicating that the rice gene evolved from a different ancestor that gave rise to other cereal prolamine genes. Developing wheat and rice endosperms were examined using ultrathin sections prepared from tissues harvested at various days after flowering. By immunocytochemical localization techniques, wheat prolamines are localized within vesicles from Golgi apparatus and in homogeneous regions of protein bodies. The involvement of the goli apparatus in the packaging of wheat prolamines into protein bodies indicates a pathway which differs from the mode of other cereal prolamines and resembles the mechanism employed for the storage of rice glutelin and legume globulins.

• Korean Journal of Community Nutrition
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• v.9 no.4
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• pp.536-544
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• 2004

To evaluate the antioxidative effect of maengjong-juk (Phyllostachys pubescens) extract coated rice in vivo system, maengjong-juk extract coated rice diets were fed to C57BL/6 mice for 16 weeks. Plasma total antioxidative capacity, hepatic lipid peroxidation, protein oxidation, activities of antioxidative enzymes and total glutathione content were measured. Plasma total antioxidative capacity was elevated significantly in maengjong-juk extract diets supplemented group in a dose dependant manner. Hepatic TBARS contents were significantly decreased in maengjong-juk extract diets supplemented group compared to high cholesterol group. Maengjong-juk extract coated rice diets suppressed the protein oxidation significantly in liver. Activities of hepatic antioxidative enzymes such as total SOD, CuㆍZn-SOD, Mn-SOD, GSH-Px and catalase activities of maengjong-juk extract coated rice diets were significantly higher than those of high cholesterol diet. Total hepatic glutathione content was significantly increased by maengjong-juk extract coated rice diets administration. According to this study, numerous antioxidative materials and phytochemicals containing in maengjong-juk extracts appear to protect antioxidative systems in C57BL/6 mice fed bamboo extract coated rice diet. (Korean J Community Nutrition 9(4): 536∼544, 2004)

• Korean journal of food and cookery science
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• v.8 no.4
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• pp.379-385
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• 1992

1. Amino acid compositions were determined by amino acid analyzer. Through the analysis of these samples, it was found that glutamic acid was the most abundant; glycine, aspartic acid, lysine and threonine were rich; and tryptophan and methionine were the limiting amino acid. 2. Albumins, globulins, gliadins and glutelins were extracted from the Kangwon hull, Kangwon rice buckwheat, and wheat. The relative proportions of protein fractions were 52.45 : 10.14 : 16.61 : 20.80% in Kangwon hull buckwheat, 21.10 : 13.80 : 28.40 : 36.70% in Kangwon rice buckwheat and 6.87 : 1.65 : 42.85 : 48.6% in wheat, in the order of albumins, globulins, gliadins and glutelins. 3. Polyacrylamide gel electrophoresis (PAGE) and SDS-polyacrylamide gel electrophoresis (SDS-PAGE) were performed to identify the subfractions of each protein fraction. The electrophoregrams of PAGE showed that the same fractions of both Kangwon hull buckwheat protein and Kangwon rice buckwheat protein had very similar electrophoretic patterns to each other respectively, but there were significant differences in the patterns between buckwheat proteins and wheat proteins.

• BMB Reports
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• v.43 no.2
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• pp.103-109
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• 2010

Modification of proteins by the reversible covalent addition of the small ubiquitin like modifier (SUMO) protein has important consequences affecting target protein stability, sub-cellular localization, and protein-protein interactions. SUMOylation involves a cascade of enzymatic reactions, which resembles the process of ubiquitination. In this study, we characterized the SUMOylation system from an important crop plant, rice, and show that it responds to cold, salt and ABA stress conditions on a protein level via the accumulation of SUMOylated proteins. We also characterized the transcriptional regulation of individual SUMOylation cascade components during stress and development. During stress conditions, majority of the SUMO cascade components are transcriptionally down regulated. SUMO conjugate proteins and SUMO cascade component transcripts accumulated differentially in various tissues during plant development with highest levels in reproductive tissues. Taken together, these data suggest a role for SUMOylation in rice development and stress responses.

• Applied Chemistry for Engineering
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• v.31 no.4
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• pp.398-403
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• 2020

In this study, six kinds of rice grown in Cheongwon area were extracted using glycolytic and proteolytic enzymes, and also antioxidant effects and water holding capacity of rice protein extracts were compared and analyzed. Protein contents of rice cultivars protein extract showed that black rice (BR) extract was the highest at 4,900 ㎍/mL, and flavored brown rice (FBR) extract was the lowest at 3,700 ㎍/mL. 2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical scavenging activity was confirmed the superior activity of more than 80.0% at a concentration of 2 mg/mL with BR and red brown rice (RBR) extracts. 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity at a concentration of 2 mg/mL with BR and RBR extracts was more than 70.0% The water holding capacity for extracts using RBR, red-kerneled brown rice (RKBR), BR and FBR was more than 110.0%. Overall, the rice protein extract using BR has excellent antioxidant and water holding capacity which can be used as a potential skin moisturizer and antioxidant functional cosmetic material.

• Preventive Nutrition and Food Science
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• v.12 no.2
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• pp.103-110
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• 2007

The protein profiles among Korean rice cultivars were assessed by total protein determination, solubility fractionation, SDS-PAGE analysis and scanning densitometry. In the extraction of protein, the SDS/urea system at a neutral pH was more efficient than that at alkaline pH. The determination of total protein showed that the protein content was similar among cultivars, ranging from 87.9 to 92.7 mg/g dry weight. Additionally, the water/NaCl-soluble protein fraction, containing 14${\sim}$16 kDa albumin and 22 kDa globulin ${\alpha}$-globulin, was also similar among cultivars, with a range of 9.94 to 11.98 mg/g dry weight. The SDS-PAGE/densitometry of total protein showed that there was no discernable difference in proteins of higher molecular weights among various cultivars, whereas the amount of lower molecular weight proteins (14${\sim}$16 kDa) is somewhat variable among cultivars. Furthermore, SDS-PAGE analysis of water/NaCl-soluble and propanol-soluble fractions indicates that there is a discernible change in the content of albumin, globulin or prolamin among cultivars. Thus, the PAGE/densitometry method, preceded by solubility fractionation, is useful for examining differences in protein profiles of rice cultivars.

• The Korean Journal of Food And Nutrition
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• v.31 no.1
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• pp.94-103
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• 2018

The quality characteristics of bread with black rice flour were investigated to find the most preferred ratio of black rice flour. Its moisture, ash content, crude protein, crude fat, amino acids, and texture were analyzed. A sensory evaluation was also performed. The moisture and crude fat of bread with black rice flour were decreased in proportion to the added amount of black rice flour, but the crude protein and ash content were increased. The volume of bread decreased as the added amount of black rice flour increased. The pH value of bread increased in proportion to the added amount of black rice flour. The value of brightness and yellowness of the dough were the highest in the control. The added amount of black rice flour was negatively correlated with the brightness and the yellowness of the dough, but was positively correlated with the redness. Total free amino acids were found, and the dough with 5% black rice flour contained the highest amount, followed by 3%, 2%, and 1%. When evaluating the storage days, the springiness and cohesiveness of bread with black rice flour they decreased with time, but the chewiness and brittleness increased. Regarding the taste, preference was given to the bread with 2% black rice flour, which had the lowest rejection rate and was not affected by time in any meaningful sense. The bread with 2% black rice flour won the highest scores in the overall preference measurement.

• Journal of Applied Biological Chemistry
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• v.58 no.4
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• pp.355-361
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• 2015

The rice protein profiles of Oryza sativa L (Koshihikari) grown under organic and conventional cultivation regimes were compared on 2-D gels to develop diagnostic marker proteins for organic rice. The selected proteins, differentially expressed between organic and conventional rice, were compared with the differentially expressed proteins of another organic and conventional rice pairing, produced at a different location. In the first comparison among conventional, no-chemical, and organic rice grown in the same region, Korea, 13 proteins exhibiting differential expression in organic and conventionally grown plants were selected. Eight of the 13 proteins were down-regulated, and the 5 remaining proteins were up-regulated from conventional to organic rice. The second comparison pairing from Kyungju, revealed 12 differentially expressed proteins, with 8 down-regulated and 4 up-regulated proteins. Ten of the differentially expressed proteins that overlapped between the two comparison sets could not be clustered into any functional group using a functional annotation clustering tool. Further comparisons using another set of conventional and organic rice, belonging to a different variety of Oryza sativa L and produced in Sanchung, revealed 8 differentially expressed proteins, 5 of which were down-regulated and 3 of which were upregulated in the organic rice. Overall, 3 differentially expressed proteins were commonly found in all three organic rice crops. These 3 proteins, along with other overlapping differentially expressed proteins, can provide a good starting point for the development of signature proteins that can be used for the authentication of organic rice with a follow-up studies with more comparison sets.