• Preventive Nutrition and Food Science
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• v.2 no.4
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• pp.301-303
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• 1997

To elucidate the contents of phytic acid and minerals in rice produced in Korea, samples of 68 verieties of brown rice and 9 varieties of polished rice were analyzed for phytic acid by colorimetric method, and Ca, Fe, Mg and Zn contents by the atomic absorption spectrophytometer. Selenium was measured by fluorometry. Averages of phytic acid content of the 68 brown rice were 12.6 g/kg, whereas that of the 8 polished rice were 1.83 g/kg on dry matter. Averages of Ca, Fe, Mg and Zn contents on the 68 brown rice were 111, 7.4, 1,068 and 19.1 mg/kg, and those of the polished rice were 45.6, 2.1, 250 and 14 mg/kg, respectively. A averge of selenium content of the brown rice was 38.3 $\mu\textrm{g}$/kg.

• Preventive Nutrition and Food Science
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• v.16 no.2
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• pp.179-183
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• 2011

This study was conducted to determine the biological activities of 70% ethanol extracts from rice husks of nine rice cultivars in Korea. The relative antioxidant activities of rice husk extracts were evaluated by determining DPPH, ABTS radical scavenging activity and reducing power. The contents of total polyphenol, flavonoid and r-oryzanol were measured by spectrophotometric methods. Among the extracts of rice husks, Nokmi rice husks tended to have the most effective antioxidant activities compared to other rice husk varieties. Seolgaeng rice husk extract showed anti-proliferative activity against cancer cell lines (MCF7 and NCI-H460), and Hongjinju rice husk extract significantly exhibited mitogenic activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1513-1517
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• 2016

Rice bran contains high amounts of fiber and various phytochemicals, including vitamin E, ${\gamma}$-oryzanol, and phenolic acids. The oxidative stabilities of corn oil added with three rice bran extracts from two rice cultivars (Dasan 1 and Ilpum) were evaluated. The three rice bran extracts were unsaponifiable matter of rice bran (USM), methanolic extract of rice bran oil (MEO), and methanolic extract of defatted rice bran (MEDR). Each sample was stored at $50^{\circ}C$ for 24 days. Oxidation of these samples was determined every 3 days by measuring the peroxide value (POV) and conjugated diene value (CDV). Vitamin E content was analyzed on day 0 and day 24. The results show that the POV and CDV values of samples increased gradually during the storage period. The order of oxidative stability was shown as BHT> MEDR> MEO> USM> control, regardless of cultivars. In the case of vitamin E, ${\alpha}$-T, ${\gamma}$-T, ${\alpha}$-T3, and ${\gamma}$-T3 contents decreased by 89%, 31%, 83%, and 32% after storage for 24 days, respectively. In conclusion, MEDR showed higher oxidative stability and may have potential as a source of natural antioxidants in the oil industry.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.526-532
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• 2017

Development, survival, and reproduction of brown planthopper (BPH) Nilaparvata lugens $St{\aa}l$ (Hemiptera: Delphacidae), were studied in laboratory at $25{\pm}2^{\circ}C$, $65{\pm}5%$ RH and a 16L : 8D hours photoperiodism on five rice cultivars of: Dongjin 1ho, Chungchungbyeo, Jangseongbyeo, Chinnongbyeo and Jungmo 1045. BPH nymphs successfully survived on all rice cultivars, although survival rate was lowest on Jangseongbyeo (36.0%). Developmental time of immature stages ranged from $11.7{\pm}0.59d$ on Jungmo 1045 to $12.8{\pm}0.59d$ on Chinnongbyeo. Reproductive period and female longevity were longest on Dongjin 1ho, Chinnongbyeo and Jungmo 1045 while highest fecundity of N. lugens being observed on these three rice cultivars. Highest and lowest net reproductive rates were calculated on rice cultivars, Jungmo 1045 and Jangseongbyeo, respectively. Mean generation time was the longest on rice cultivar Dongjin 1ho. Respective descending order of intrinsic rates of population increase were on Jungmo 1045, Chinnongbyeo, Dongjin 1ho, Chungchungbyeo and Jangseongbyeo. These population parameters showed that N. lugens can successfully survive and reproduce on Chinnongbyeo and Jungmo 1045.

• Proceedings of the Korean Society of Crop Science Conference
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• 1991.05a
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• pp.52-53
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• 1991

• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.266-267
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• 2006

• Proceedings of the Korean Society of Crop Science Conference
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• 1994.06a
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• pp.64-65
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• 1994

• Proceedings of the Korean Society of Crop Science Conference
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• 1992.05a
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• pp.82-83
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• 1992

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2002.11a
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• pp.69-72
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• 2002

작물생육모형은 작물의 광합성과정 등 주요 생리과정을 정량적으로 연구하기 위해 30여 년 전부터 소개되기 시작하였다. 다양한 환경조건 하에서 생장 및 발육의 종합적인 모의가 가능한 정도로 발전한 최근에는 주요 식량작물에 대해 실용수준의 모형들이 개발되어 다양한 용도로 쓰이고 있다.(중략)

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2002.11a
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• pp.73-76
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• 2002

남한 벼 품종들의 북한 서부지역 적응성을 평가하고자 11개 품종의 유전적 특성을 갖도록 모수가 조정된 벼 생육모형 CERES-rice를, 선행연구에 의해 생성된 496개 재배구역별 일기상 자료를 이용하여 30년 간씩 구동함으로써 각 재배구역의 품종별 기후학적 적응성을 평가하였다.(중략)