• Journal of Life Science
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• v.28 no.10
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• pp.1132-1139
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• 2018

The stability of diverse cellular proteins in eukaryotes is regulated via ubiquitination. Moreover, E3 ligase plays a crucial role in determining substrate specificity and transfers ubiquitins into the substrates during the ubiquitination process. As a type of multi-subunit E3 ligase, cullin4 (CUL4)-based E3 ligase (CRL4) complex is involved in a variety of cellular processes, such as hormonal and stress responses in plants. In spite of several reports on the versatile roles of CRL4 in various signalings in Arabidopsis, CRL4's function in rice has been poorly known. To learn about CRL4-mediated cellular processes in rice in more detail, OsCUL4 that exhibits the highest homology with Arabidopsis CUL4 was isolated, and its expression patterns in various tissues and in response to plant hormones and abiotic stresses were monitored. Exogenous application of ABA or cytokinin increased the transcript levels of the OsCUL4 gene. Moreover, OsCUL4 was significantly upregulated in response to drought and salt stresses. These findings imply that OsCUL4 may be functionally related to ABA- and/or cytokinin-mediated cellular responses. OsCUL4 directly interacted with OsDDB1, an adaptor protein of CRL4, indicating that OsCUL4 can act as a scaffold protein of CRL4. An expression study on the OsCUL4 gene from this report could be used as a starting point to elucidate cellular responses in which a CRL4-mediated ubiquitination process is involved in rice.

• The Korean Journal of Pesticide Science
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• v.7 no.2
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• pp.108-116
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• 2003

A series of new quinclorac family, herbicidal 3-phenyl-5-(3,7-dichloro-8-quinolinyl)-1,2,4-oxadiazole derivatives as substrate were synthesized and their growth inhibition activity $(pI_{50})$ against root and shoot of rice plant (Oryza sativa L.) and barnyard grass (Echinochloa crus-galli) were determined. And then comparative molecular field analysis (CoMFA) and molecular holographic quantitative structure- activity relationship (HQSAR) were compared in terms of their potential for predictiability. The statistical results were suggested that HQSAR based model had better predictability than CoMFA model. The selective factors to remove barnyard grass take electron withdrawing groups which can be created positive charge and steric bulky on the phenyl ring. Results revealed that the unknown 2,6-dichloro-substituent, U5 and 2,4,6-trichloro-substituent, U6(${\Delta}pI_{50}$=CoMFA: 1.18 & HQSAR: 1.82) were predicted as compound with higher activity and selectivity.

• Korean Journal of Plant Tissue Culture
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• v.24 no.5
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• pp.295-303
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• 1997

To investigate the response on feeder cell cultures, protoplasts isolated from cell suspensions initiated from mature seed scutellum-derived callus of the Japonica rice variety Taipei 309, were cultured on filter membranes under various conditions. The effects of various factors, such as gelling agents, feeder cell and protoplast densities, species of feeder cells and heat shock treatment, have been investigated to improve protoplast plating efficiencies on filter membranes. Maximum protoplast plating efficiencies were obtained when protoplasts were cultured on KPR medium semi-solidified with Sea Plaque agarose at a density of $5\;\times\;10^{5}\;ml^{-1}$ protoplasts in the presence of Lolium multiflorum as feeder cells (0.5 ml pcv per 10 ml of protoplast culture medium). Pre-culture heat shock treatments for 1 min. and 5 min. to the protoplasts did not give any appreciable increase on the plating efficiency of protoplasts in the presence of feeder cells. Maltose-supplemented medium was superior for plant regeneration from protoplast-derived colonies compared with medium containing only sucrose. The plants were transferred to the glasshouse, flowered and were fertile.

• Food Science and Preservation
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• v.23 no.5
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• pp.673-679
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• 2016

This study was performed to verify the possibility of manufacturing a germinated aromatic rice tea, which was roasted at 200, 250, and $300^{\circ}C$ each for 10, 20, and 30 min. The roasted aromatic rice was analysed physicochemical properties, sensory characteristics and aromatic compounds. The total polyphenol content and DPPH radical scavenging activities of the germinated aromatic rice increased as the roasting temperature and time increased. Total soluble solid contents, turbidity and browning index of the germinated aromatic rice tea also increased was the roasting temperature and roasting time increased. The pH did not change by roasting. The main aromatic components in roasted germinated aromatic rice tea were 2-methyl butanal, 3-methyl butanal, benzaldehyde and nonanal, which increased according to increasing temperature and time. However, those favorable aroma components were decreased at more than $300^{\circ}C$ of roasting temperature. In addition, methyl benzene, pentanol were increased which affect odor aroma. The sensory score of germinated aromatic rice tea also increased with high roasting temperature and time. However, aromatic rice roasted at a higher temperature ($300^{\circ}C$) showed lower sensory score. Therefore roasting temperature and time must be controlled for manufactureing high quality of germinated aromatic rice tea, and the optimun roasting conditions were $250^{\circ}C$ and 30 min, which provide best physicochemical characteristics of aromatic rice tea.

• Food Science and Preservation
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• v.24 no.8
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• pp.1060-1066
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• 2017

This study was conducted to develop rice cookies added with young persimmon fruits. Effects of varying amounts (0-12%) of the fruit powder from a young astringent persimmon fruit (picked at July) on the quality characteristics of rice cookies were studied. Ingredients [rice (Oryza sativa subsp. japonica 'Ilpum') flours, persimmon (Diospyros kaki Thunb. 'Cheongdobansi') powder, sugar, butter, salt, baking powder, egg] were mixed, cut (thickness 3 mm, diameter 35 mm), baked at $170-180^{\circ}C$ for 9 min, cooled, and packaged in polyethylene/nylon bags. The loss rate and spread factor after baking of cookies increased and then decreased with an increase in the amount of fruit powder added. The moisture content and color values ($L^*$ and $a^*$) of cookies decreased with an increase in the amount of the persimmon powder added. Phenolic compounds content and DPPH radicals scavenging activity increased with an increase in persimmon powder content; in particular, the DPPH activity of the cookies sharply increased after the addition of 3% persimmon powder. These results suggest that the addition of the young persimmon fruit powder affected the quality characteristics of rice cookies and this fruit powder (approximately 3%) can be utilized as an additive during rice cookie processing.

• Food Science and Preservation
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• v.24 no.6
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• pp.758-763
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• 2017

In this study the effect of rice addition on the quality of beer was investigated. Pilot-scale brews were performed with addition ratios of 10, 20, 30, and 40% of brown rice (Oryza sativa L. cv. Hangaru) which were compared with 100% malt beer and commercial beers in terms of quality. Alcohol content of beer was between 3.93 to 4.40%. The total sugar content increased when the rice percent was increased. The pH range of beer were 4.32 and 4.60, which were no significant differences found among by the rate of rice added. Total acidity and amino-acidity decreased corresponding to increasing percent of rice, on the other hand, lightness of beer was increased the increase in percent of rice, while redness and yellowness of beer were decreased. The study demonstrated that the increases of rice addition in beer provided some positive effects on beer quality by decreasing bitterness where as improving beer color.

• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.198-203
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• 2015

This study was performed to evaluate changes in the chemical composition of germinated rough rice with high hydrostatic pressure treatment (HPT). Rough rice was germinated at $37^{\circ}C$ over 6 days (control), and then subjected to HPT at 30 MPa for 24 h. The highest crude protein content was 9.54% in the control sample after 6 days of germination. Crude lipid content increased from 2.04-2.74% (control) to 2.27-3.10% (HPT). HPT samples showed higher values of total free sugar and glucose content than those of the control. The total amino acid value was not significant, but the essential amino acid content increased from 0.45-5.09 mg/g in the control to 1.57-5.30 mg/g in the HPT sample. The major fatty acids were found to be palmitic, oleic, and linoleic acid. The content of oleic acid decreases with HPT, whereas that of linoleic and linolenic acid increased slightly during the initial stages of germination. These results suggest that HPT after germination efficiently depolymerizes chemical components and enhances the content of essential nutrients.

• Journal of Life Science
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• v.26 no.6
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• pp.727-736
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• 2016

Rice (Oryza sativa L.) is one of the major cereal crops for consumption by the world’s population. Recently, various colored rice, such as white, red, brown, green, and black rice, have caught the attention of world consumers. The commercial name ‘black rice’ contains a high amount of anthocyanins in pericarp, which increases nutritional value. Moreover, anthocyanin in black rice possesses biomedical properties, including anti-oxidant, anti-cancer, and anti-inflammatory effects in humans. In genetics, black rice has a dominant PURPLE PERICARP (Prp) trait governed by two genes, Pb and Pp, which are involved in the synthesis of cyanidin-3-O-glucoside (C3G). Since the publication of a report by Nagai at 1921, the genetics and physiological studies of black rice driven by Prp traits are still unable to understand the relevant genes and their roles. However, with the increased demand for anthocyanin-rich black rice as a functional food for human health, it has become urgent to develop highyielding anthocyanin-rich varieties of rice. We explored many years in the genetics of purple pericarp trait, anthocyanin biosynthesis in pericarp during seed development, and, consequently, their products in relation to different physiological and agronomic traits. In this review, we summarized the anthocyanin biosynthesis in pericarp, emphasizing the inheritance pattern of the trait and functions of their products on different physiological and agronomic traits, including the yield of black rice.

• Journal of Life Science
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• v.27 no.12
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• pp.1393-1402
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• 2017

In plants, calcium ($Ca^{2+}$)-dependent protein kinases (CDPKs) are important sensors of $Ca^{2+}$ signals. Previous research demonstrated the expression of the OsCPK11 gene in various tissues at the transcription level, but its developmental and biochemical functions at the protein level were not determined. This study was aimed to identify biochemical characteristics of OsCPK11. GST- OsCPK11 was expressed in E. coli and used for an in vitro kinase assay. Biochemical analyses identified OsCPK11 as a CDPK. OsCPK11 autophosphorylated itself and transphosphorylated histone III-s and MBP as substrates in the presence of $Ca^{2+}$. The activity of the recombinant OsCPK11 was influenced by $Mg^{2+}$, with optimum activity detected at pH 7.0-7.5. OsCPK11 activity was not affected by $Mg^{2+}$, $Mn^{2+}$, or $Na^+$ in the presence of a high level of $Ca^{2+}$. Autophosphorylation of OsCPK11 decreased $Ca^{2+}$ sensitivity of OsCPK11. An anti-OsCPK11 rabbit antibody recognized 95.5 kD of GST-OsCPK11, as shown by an immunoblot analysis. These results shed light on the function of OsCPK11 in $Ca^{2+}$-mediated signaling in rice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.833-840
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• 1997

Differentiation and degeneration of spikelets in paddy rice has been studied in high yielding Indica$\times$Japonica hybrid cultivar, Milyang 23 and a Japonica type cultivar, Koshihikari. Germinated seeds planted in 5000$^{-1}$ a pots filled with submerged soil and cultured under natural conditions. The young panicles of main stem were continuously dissected and observered by Cryo-SEM from the panicle initiation stage, and investigated about formation position of the differentiation and degeneration spikelet within a panicle of 7 days after heading. The degeneration of spikelet appeared simultaneously throughout panicle just after closure of spikelet by the palea and lemma. Differentiated and degenerated spikelets per panicle were about 240, 80 for Milyang 23 and 87, 6 for Koshihikari, respectively. The spikelets degeneration in Milyang 23 was mainly on the secondary and tertiary branch which were developed from primary branch of middle-basal panicle node and hardly not the spikelets of primary branch, and degeneration rate of secondary and tertiary rachis branch and spikelets for Milyang 23 were 2.5 times greater than those of Koshihikari. The proper relation equation between total differentiation or normal spikelets number per panicle(Y) and each rachis branch number were different between cultivars, Le., Y=5.5X$_1$＋3.0X$_2$ for Koshihikari as previously proposed, but those of Milyang 23, Y=5.7X$_1$＋3.5X$_2$＋2.8X$_3$ for total differentiation spikelets and Y=5.6X$_1$＋3.2X$_2$＋2.4X$_3$ for normally developed spikelets, where X$_1$, X$_2$, X$_3$ are number of primary, secondary, tertiary rachis branch, respectively.