• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.69-69
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• 2017

Due to the lack in storage facility, considerable amount of rice is stocked in the open air, which causes increased stale flavor and deteriorates palatability and merchantable quality. Lipoxygenase-3(LOX-3) is involved in the production of volatile constituents in stored rice, and the development of stale flavor is delayed in LOX-3 null rice. LOX activity in the rice grain is localized in bran fraction and the tropical Japonica cultivar 'Dawdam' was reported that the absence of LOX-3 is inherited as a simple recessive trait. Also, it was reported that the peroxidation of unsaturated fatty acids occurs at lower levels in the 'Dawdam' bran fraction during storage than in rice varieties with LOX-3. This study was conducted to develop LOX-3 null rice lines using 'Dawdam' and investigate changes of physicochemical properties of the lines stored at different storage temperatures and periods. So we analyzed texture, toyo glossiness value, germination rate and lipoxygenase activity of 15 LOX-3 null rice lines on the condition of which rough rice had been stored at different temperatures (high temperature condition at $35^{\circ}C$ and low temperature condition at $15^{\circ}C$ for 4months. Hardness and stickiness of the lines tendered to be increased when it was stored at high temperature and adhesiveness, springiness, cohesiveness and chewiness was not considerably different according to storage temperatures and periods. The germination rate of HR29062-B-98-2-1-B among LOX-3 null rice lines was higher than another lines, 99.3, 94.0% after 4months stored at low temperature and high temperature, respectively. The lipoxygenase activity was 3,304, 1,601unit/mg protein after 4months stored at low temperature and high temperatures, respectively. So, it is thought that this line will be useful to breed rice varieties with high storability after tested on agricultural traits.

• Applied Chemistry for Engineering
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• v.5 no.3
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• pp.478-500
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• 1994

The preparation of potassium hexatitanate whisker by flux method was investigated. In this study, 8 types synthesis of flux such as $V_2O_5$, $Bi_2O_3$, $B_2O_3$, $Pb_3O_4$, KCl, $K_4P_2O_7$, $K_2WO_4$ and $K_2MoO_4$ were tested to find a suitable flux for the synthesis of potassium hexatitanate whisker. Effects of various reaction variables such as reaction temperature, time, $TiO_2$ mole ratio to $K_2CO_3$, flux mole ratio to the mixture of $K_2CO_3$ and $TiO_2$, and slow-cooling treatment on the crystallization of potassium hexatitanate whisker were investigated. $K_2MoO_4$ and $K_2WO_4$ were better flux than others tested for the synthesis of potassium hexatitanate. In the presence of $K_2MoO_4$ or $K_2WO_4$ flux, the optimum condition for the synthesis of potassium hexatitanate whisker was that reaction temperature of $1000{\sim}1100^{\circ}C$, reaction time of 5 hours, $TiO_2$ mole ratio to $K_2CO_3$ of 6.0, and flux mole ratio to mixture ($K_2O+nTiO_2$) of 4.0. Slow-cooling treatment showed good effect on the growth of long fibrous potassium hexatitanate.

• The Korean Journal of Mycology
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• v.26 no.4 s.87
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• pp.450-457
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• 1998

The cryparin of Cryphonectria parasitica belongs to a cell wall associated fungal hydrophobin. The cryparin, though it is encoded by a single copy gene, is known for the high expression during the liquid culture of C. parasitica, and it turns out that 22% of total mRNA was transcribed for cryparin at 48hr after the liquid culture. In addition, it is also known as one of down-regulated fungal proteins by the presence of double stranded RNA virus, Cryphonectria hypovirus 1. In previous studies (Kim et al., 1999), we have constructed a cryparin-null mutant by replacing the cryparin gene with hygromycin B resistance gene due to site directed homologous recombination. In order for the promoter analysis of cryparin which seems to be very strong as well as mycoviral specific, it is preferable to have a strain with only a target promoter replaced and a discernable target site for incoming vectors. However, the cryparin-null mutant revealed the presence of an additional copy of transforming vector except the one which replaced the cryparin gene. In addition, the cryparin-null mutant did not contain any markers for targeted integration of incoming vectors. This prompts us to design an experiment to obtain a strain for promoter analysis of cryparin gene. A different mating type strain EP6(Mata, $met^-$) was mated with the cryparin-null mutant ${\triangle}$Crp194-7(MatA, Crp${\triangle}$::hph) to make the progenies with only a single replacement vector and $met^-$ characteristic remained. Nutritional assay as well as Southern blot analysis revealed that the progeny, ${\triangle}$Crp194-a6, was the methionine auxotroph with a single replacing vector in genome. Northern blot analysis and PAGE showed that there was no cryparin produced in this bred strain either.

• Journal of Korean Society of Forest Science
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• v.94 no.1 s.158
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• pp.39-44
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• 2005

An effective micropropagation system for Liriodendron tulipifera L via somatic embryogenesis was established using immature seeds. Immature seeds from five individual trees were bisected longitudinally and cultured on two basal media (MS and B5) containing different combinations of 2,4-D and TDZ to induce callus and embryogenic tissue under light ($40{\mu}mol\;m^{-2}s^{-1}$, 16 hr/day) or complete darkness at $25{\pm}2^{\circ}C$. There was no distinctive difference on callus and embryogenic tissue induction between the two basal media with PGRs. Optimum culture medium appeared to be MS medium supplemented with 1.0mg/L 2,4-D and 0.01mg/L TDZ plus 3% sucrose. Nonembryogenic callus induction rate was not significantly different among the genotypes. However, However, the embryogenic callus induction frequency differed greatly by the genotypes ranging from 55% to 72% when cultured in the dark. Generally, the cultures maintained in the dark tended to show normal somatic embryo development as well as embryogenic tissue formation and this was confirmed by histological examination. Above results suggest that a proper selection of mother tree and dark culture condition are necessary to optimize somatic embryogenesis system of Liriodendron tulipifera.

• Microbiology and Biotechnology Letters
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• v.41 no.1
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• pp.33-43
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• 2013

A bacterium producing a fibrinolytic enzyme was isolated from Cheonggukjang. The bacterium was identified as a strain of Bacillus amyloliquefaciens by 16S rDNA analysis and designated as B. amyloliquefaciens HC188. The optimum culture medium appeared to be one containing 0.5% (w/v) maltose and 0.5% (w/v) soytone. Bacterial growth in the optimal medium at $37^{\circ}C$ reached the stationary phase after 27 h of incubation and the fibrinolytic enzyme showed optimum activity at 24 h. The enzyme was purified by 20-80% ammonium sulfate precipitation, CM Sepharose fast flow ion exchange chromatography, and Sephacryl S-200HR column chromatography. Its specific activity was 38359.3 units/mg protein and the yield was 5.5% of the total activity of the crude extracts. The molecular weight was 24.7 kDa and the amino acids of the N-terminal sequence were AQSVPYGVSQIKAPA. The fibrinolytic enzyme activity had an optimum temperature of $40^{\circ}C$ and an optimum pH of 8.0, and the enzyme was stable in the ranges $20-40^{\circ}C$ and pH 6.0-8.0. Enzyme activity was increased by $Ca^{2+}$ and $Co^{2+}$ but inhibited by $Cu^{2+}$, EDTA, and PMSF. It is suggested that the purified enzyme is a metallo-serine protease.

• Journal of Life Science
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• v.18 no.12
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• pp.1705-1711
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• 2008

To investigate the relationship between cold stress and the activity of ascorbate peroxidase(APX), dehydroascorbate reductase (DHAR), mRNA expression level of two enzymes, hydrogen peroxide content was studied in lettuce leaves under stress condition imposed by cold stress at $4^{\circ}C$ for 24 hr in the dark and following recovery at $20^{\circ}C$ from cold stress. Hydrogen peroxide content increased gradually in lettuce leaves during cold stress, but decreased slightly following recovery from cold stress. Soluble protein content, however, decreased gradually during cold stress, and then rapidly returned to normal levels following recovery. Total chlorophyll content decreased gradually during cold stress, and then keep constant following recovery. The patterns of chlorophyll a and b content similar to that of total chlorophyll content, and carotenoid content didn't change. The ratio of chlorophyll a and total chlorophyll was increased during cold stress, but decreased with rapid during cold stress, and then the ratio returned to normal levels following recovery. During cold stress, the activity of APX and DHAR in the lettuce leaves increased dramatically, and also transcript levels of mRNA of APX and DHAR, as determined by probing 32P-labeled single stranded RNA of APX and DHAR, highly increased and returned to normal levels following recovery, respectively. Relationship between APX and DHAR activity and hydrogen peroxide highly related ($R^2$=0.8715 and 0.8643), whereas between hydrogen peroxide and total chlorophyll content and soluble content related reversely ($R^2$=0.5021 and 0.8915).

• Food Science of Animal Resources
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• v.27 no.1
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• pp.47-52
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• 2007

Quality evaluations of seasoning chicken wing treated with pine needles during storage of 6 days at $4^{\circ}C$ were assessed. Seasoning chicken containing 0.5-1.3% (w/w) pine needle during storage at $4^{\circ}C$ was allowed to the growth of Staphylococcus aureus. pH values of seasoning chicken containing pine needles after 6 days of storage were not significantly different (p>0.05) than those of the controls. The rate of drip loss on seasoning chicken containing pine needles after 24 hr of storage was significantly different (p<0.05) than that of the controls. Sensory scores of seasoning chicken containing 0.8-1.3% pine needles for odor and flavor were in the "liked more" to typical category during storage of 6 days at $4^{\circ}C$. For odor and flavor scores, seasoning chicken containing 1.0-1.3% pine needles compared to the controls and other treatments increased during storage days due to fresh odor of pine needles. Seasoning chicken containing 0.5-1.3% pine needles after 6 days of storage were no significantly different levels (p>0.05) of Hunter color $L^*$ values compared to controls. Hunter color $a^*$ and $b^*$ values of seasoning chicken containing 0.5-1.3% pine needles after 6 days of storage were significantly different (p<0.05) than those of the controls.

• Applied Biological Chemistry
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• v.40 no.6
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• pp.472-477
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• 1997

The effects of roasting Cassia tora L. were investigated for proximate composition, color, volatile flavor profile, microbial growth and alcohol fermentation. While moisture, protein and fat contents decreased with increasing roasting temperature, fiber and ash contents increased. The L, a and b values of Cassia tora L. extracts decreased with increasing temperature, and only a small difference in total color difference$({\Delta}E)$ was observed. A little difference in major flavor components between raw and roasted treatment was found during roasting. Furfuryl alcohol, a major component of coffee flavor, was separated from Cassia tora L. extracts extracted with ethyl ether. The yeast growth was the highest on the water-extract of Cassia tora L. roasted at $160^{\circ}C$. With increased levels of water-extract at $160^{\circ}C$, S. cerevisiae grew rapidly for 24 hr incubation and the growth rate was higher than the unroasted control group. The growth rate of Bacillus subtilis was the highest in a treatment of 0.5% concentration. Little differences in ${\alpha}-amylase$ produced from Bacillus subtilis were observed among the treatment groups. The total alcohol content increased with increasing roasting temperature during alcohol fermentation.

• Korean Journal of Community Nutrition
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• v.13 no.6
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• pp.922-933
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• 2008

The purpose of this study was to investigate the effects of nutrition education using Food Exchange System on elementary students' nutrition knowledge, dietary attitude and nutrients intake. Nutrition education lessons (40 min /lesson, 4 times), '5 major nutrients and functions', '6 food groups and sources of 6 food groups', 'good choice of snacks and eating out' as class lesson, 'daily needed energy and food exchange units' as individual lesson, were provided to 70 elementary students (4th grade 33 students, 5th grade 37 students) in Jeonbuk Province. We assessed the changes in nutrition knowledge, dietary attitude, food habit using a questionnaire and nutrient intake using 24 hr recall method by nutrition education. In nutrition knowledge, there were significant increases in scores of 'functions of carbohydrate', 'functions of protein', 'functions of lipid', 'foods of carbohydrate', and 'foods of lipid'. In dietary attitude, there were significant increases in scores of 'taking a meal with joy', 'taking a meal at ease', 'taking a meal with sufficient protein intake' and 'taking a meal without spicy foods' by nutrition education. There were significant changes in the type of breakfast and in the frequency of snacks. After education, in type of breakfast, it showed higher number of students ate rice oriented meal than they did before education. and in frequency of snacks, it showed lower number of students ate snacks 'over 3 times' than they did before education. In Carbohydrate : Protein : Fat (CPF) ratio (%), it was significantly changed from 55.8 : 17.7 : 26.6 to 63.6 : 15.3 : 21.1. In evaluation of nutrient intake by Dietary Reference Intakes for Koreans (KDRIs), vitamin A, thiamin, niacin, vitamin $B_6$, calcium, phosphate, iron and zinc showed positive changes in distribution of number of children by intake level. That is, there were significant improvements in intakes of vitamin A, thiamin, niacin, vitamin $B_6$, calcium, phosphate, iron and zinc. These results showed that nutrition education using Food Exchange System for elementary students improved nutrition knowledge, dietary attitude and nutrients intake. It suggest that nutrition education using Food Exchange System may improve dietary behaviors and reduce an incidence of obesity in elementary students.

• Journal of Biosystems Engineering
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• v.3 no.2
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• pp.100-113
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• 1978

Drying grain with conventional artificial drying methods requires great quantities of petroleum fuels. Depletion of fossil fuel increases the need of the utilization of solar energy as an alternative to petroluem fuels for drying grain , an energy intensive agricultural operation. Many techniques for the utilization of solar energy in grain drying have been developed, however, there are many problems in adopting solar energy as an energy sources for drying grain. Futhermore, very little research has been done on solar grain drying in Korea. This study was conducted to evaluate the availability of solar energy for drying of rough rice in Chuncheon, Suweon, and Jinju areas based on 50year meteorological data, and to analyze experimentally the performance of a solar air collector for dying grain, and to find the effects of solar heated air compared to unheated air on the rate of drying and energy consumption required for drying of rough rice. The results of this study was may be summarized as follows ; 1. Monthly average daily total radiation on a horizontal surface in October was 260.6 ly/day for Chuncheon, 240.3 ly/day for Suweon , and 253.4 ly/day for Jinju area, respectively. 2. the ratio of monthly average daily diffuse radiation to daily total radiation on a horizontal surface was approximately 0.41 for Chuncheon, 0.45 for Suweon, and 0.44 for Jinju area, respectively. 3. Although the statistical distribution curves of daily total radiation for the three locations were not identical , the differences among them were not large and may be neglected for many practical purposes. 4. I was estimated that the optimum tilting angle of the collector in October was approximately 46 degrees for Chuncheon and Suweon and 45 degrees for Jinju. 5. The ratio of the total radiation on a optimum tilting plane to that on a horizontal plane was estimated to be 1.36 for Chuncheon, 1.31 for Suweon, and 1.27 for Jinju , respectively. 6. The collection efficiency of the solar air collector ranged from 47. 8 to 51. 5 percent at the air flow rates of 251. 1-372.96 $m^3$/hr. High efficiency remained nearly , constant during the best sunshine hours, 10 a.m. to 2 p.m. and decreased during other hours. More energy was collected as the air flow rate incresed. 7. The average temperature rise in the drying air from the solar collector for the test period varied from $6.5^\circC$ to $21.8^\circC$ above the ambient air temperature. 8. Solar-dried rough rice averaged 13.7 percent moisture (w.b.) after 130 hours of drying with the air flow rate of 1. 64 ccm/$m^3$, and rough rice dried with natural air averaged 15.1 percent moisture (w.b.) after 325 hours of drying with the same air flow rate. 9. Energy saving of 2.4 kwh per $m^3$ percentage point of moisture removed was obtained from solar heated air drYing. The solar bin used 53.3 percent less energy per percentage point of moisture removed than the natural air bin.