• 분석과학
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• 제37권1호
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• pp.12-24
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• 2024

In this study, laser-induced breakdown spectroscopy (LIBS) was used to estimate the degree of rice polishing. As-threshed rice seeds were dehusked and polished for different times, and the resulting grains were analyzed using LIBS. Various atomic, ionic, and molecular emissions were identified in the LIBS spectra. Their correlation with the amount of polished-off matter was investigated. Na I and Rb I emission line intensities showed linear sensitivity in the widest range of polished-off-matter amount. Thus, univariate models based on those lines were developed to predict the weight percent of polished-off matter and showed 3-5 % accuracy performances. Partial least squares-regression (PLS-R) was also applied to develop a multivariate model using Si I, Mg I, Ca I, Na I, K I, and Rb I emission lines. It outperformed the univariate models in prediction accuracy (2 %). Our results suggest that LIBS can be a reliable tool for authenticating the degree of rice polishing, which is closed related to nutrition, shelf life, appearance, and commercial value of rice products.

• Preventive Nutrition and Food Science
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• 제2권4호
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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.

• 한국식품과학회지
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• 제28권2호
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• pp.360-365
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• 1996

벼(Oryza sativa L.)의 가식부인 쌀의 brassinosteroid 활성물질의 존재를 구명하기 위하여 벼를 도정하여 미강과 백미를 얻고 이들을 각각 MeOH로 추출하여 얻어진 추출물을 rice inclination test의 생물검정법으로 검정한 결과 활성이 인정되었다. 각각의 추출물을 생물검정법을 지표로 용매분획, silica gel adsorption chromatography, Sephadex LH-20 column chromatography, charcoal adsorption chromatography 등의 수법으로 brassinosteroid 활성물질을 정제하고, silica gel adsorption chromatography, TLC 등에 의해 활성본체를 분리하고 각 활성획분을 HPLC에 의해 활성본체 구명을 시도한 결과 미강의 활성획분에서는 castasterone과 teasterone이 동정되었다. 완숙된 쌀에서 brassinosteroid 활성물질의 확인 및 동정은 본 연구가 최초로 생각되며, brassinosteroid 활성물질은 주로 미강에 존재하였으며, 그 함량은 g중량당 castasterone이 0.15 ng 이고 teasterone은 0.37 ng 수준이었다.

• Journal of Radiation Protection and Research
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• 제27권3호
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• pp.127-146
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• 2002

원자력 사고후 시간경과에 따른 작물체내 핵종 농도를 보다 현실적으로 예측할 수 있는 방법을 수립하고 단위 건침적에 대하여 백미와 배추내 $^{90}Sr$ 및 $^{137}Cs$의 50 년간 농도를 예측하였다. 비생육기 사고의 경우 농도는 두 핵종 모두 시간경과에 따라 서서히 감소하였고 50 년 내내 $^{90}Sr$이 $^{137}Cs$보다 높았다. 생육기 사고의 경우 처음 1년간 농도는 비생육기 사고에 비해 대체로 $^{90}Sr$은 최고 30 배, $^{137}Cs$은 최고 1,000 배 정도까지 높았다. 50 년간의 누적농도는 백미에서는 비생육기 사고의 경우 $^{90}Sr$이, 생육기 사고의 경우 $^{137}Cs$이 더 높았으나 배추에서는 어느 경우에나 $^{90}Sr$이 더 높았다. 생육기 사고시 50 년간의 누적농도에 대한 지배적 경로는 대체로 $^{90}Sr$의 경우 뿌리흡수, $^{137}Cs$의 경우 작물체 직접오염이었다. 재부유의 영향은 무시할 수 있을 정도였다. 예측결과에 입각하여 사고 조건별로 대책의 방향을 제시하였다.

• 한국환경농학회지
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• 제34권4호
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• pp.260-267
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• 2015

BACKGROUND: The current study was conducted to examine the species specific accumulation of Cd and Pb in 11 crop species (Soybean, Sesame, Corn, Polished rice, Carrot, Potato, Garlic, Spring onion, Chinese leek, Red pepper, Eggplant), through cultivating them under the same condition with metal contaminated soils.METHODS AND RESULTS: Eleven crop species were cultivated in three different soils contaminated with Cd and Pb and harvested. Edible parts of each crop was pretreated and analyzed to determine Cd and Pb concentrations, and subsequently bioconcentration factors (BCFs) were calculated. In general, the crops of which seeds are used as food showed high concentrations of both Cd and Pb. For instance, Cd concentrations in crops cultivated in Soil A was in the order of soybean (0.432 mg kg^-1) > sesame (0.385) > polished rice (0.176) > carrot (0.116) > corn (0.060) > red pepper > (0.047) > potato (0.044) > egg plant (0.025) > garlic (0.023) > spring onion (0.016) > Chinese leek (0.011). BCFs showed the same order.CONCLUSION: From this study, it can be conclude that seeds plants should not be cultivated in Cd and Pb contaminated soils to secure food safety from metal contaminated soils.