Myoung-Gun Choung | Kangwon National University (original) (raw)

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Research paper thumbnail of Evaluation of Sesquiterpenoids Content and Growth Characters in Clonal Lines from a Cross between Atractylodes japonica Koidz. ex Kitam. and A. macrocephala Koidz

The Korean Journal of Medicinal Crop Science, 2006

Research paper thumbnail of Development of Forchlorfenuron Residues in Agricultural Commodities Using HPLC-UVD/MS

한국농약과학회 학술발표대회 논문집, Apr 1, 2017

Research paper thumbnail of Evaluation of the Vitamin B Content of Edible Insects

Journal of the Korean Society of Food Science and Nutrition

Research paper thumbnail of The Phenolics and Antioxidant Properties of Black and Purple versus White Eggplant Cultivars

Molecules

The total phenolic content, anthocyanins, phenolic acids, antioxidant capacity and α-amylase inhi... more The total phenolic content, anthocyanins, phenolic acids, antioxidant capacity and α-amylase inhibitory activity of black (Aydin Siyahi), purple (Kadife Kemer) and white (Trabzon Kadife) eggplants grown in Turkey were subjected to a comparative investigation. The black cultivar exhibited the highest total phenolic (17,193 and 6552 mg gallic acid equivalent/kg fw), flavonoid (3019 and 1160 quercetin equivalent/kg fw) and anthocyanin (1686 and 6167 g delphinidin-3-O-glucoside equivalent/kg fw) contents in crude extracts of the peel and pulp. The majority of the caffeic acid was identified in the ester (2830 mg/kg fw) and ester-bound (2594 mg/kg fw) forms in the peel of ‘Kadife Kemer’ and in the glycoside form (611.9 mg/kg fw) in ‘Aydin Siyahi’, as well as in the pulp of these two eggplants. ‘Kadife Kemer’ (purple eggplant) contained the majority of the chlorogenic acid in free form (27.55 mg/kg fw), compared to ‘Aydin Siyahi’ in the ester (7.82 mg/kg fw), glycoside (294.1 mg/kg dw) an...

Research paper thumbnail of Non-destructive Near Infrared Reflectance Spectroscopic Technique for Selecting High Protein and Oil Soybean Lines

Research paper thumbnail of Anthocyanin 함량이 높은 감자 신품종 "자영

`자영`은 2003년 `대서` 품종과 AG34314 계통 간의 교잡후대에서 유래되었으며, 국립식량과학원 고령지농업연구센터의 감자육종 프로그램을 거쳐 선발되었다. 2006년과 ... more `자영`은 2003년 `대서` 품종과 AG34314 계통 간의 교잡후대에서 유래되었으며, 국립식량과학원 고령지농업연구센터의 감자육종 프로그램을 거쳐 선발되었다. 2006년과 2007년 대관1-104호라는 계통명으로 지역적응시험을 수행하여 주요생육특성, 괴경특성, 수량성 및 병해특성을 검토하였으며, 2007년 `자영`으로 명명하여 국립종자관리원에 신품종으로 출원하였다. `자영` 감자는 모양이 비교적 둥글고 눈이 얕으며 껍질과 속이 모두 자주색이다. ha당 평균 수량은 37.4톤이었고 봄재배에서 가장 높은 수량성을 나타냈다. `자영`은 감자더뎅이병과 잎말림바이러스병에 높은 저항성을 나타내었으나, 역병에는 감수성이었다. 건물함량은 비교적 높은 20.3%로서 칩가공용으로도 적합하였다. 안토시아닌 함량은 가을재배에서 가장 높은 43.7 mg/100 g이었고, 작형별 평균 함량은 `자심` 품종보다 4.7배 정도 더 많았다.

Research paper thumbnail of Characterization of Soybean Isoflavones Using LC/ES-MS

Research paper thumbnail of Characteristic Changes in Brown Rice (Oryza sativa L.) Cultivars of 3 Ecotypes During Different Storage Conditions

Food Science and Biotechnology, 2009

The aim of this study investigated the fluctuations of 3 characters from 3 ecotypes [early ripeni... more The aim of this study investigated the fluctuations of 3 characters from 3 ecotypes [early ripening (ER), middle ripening (MR), and late ripening (LR)] of 20 Korean brown rice cultivars in different storage systems [time: 12 and 24 weeks, temperature: low (10℃) and room (25℃)]. With increase of storage time and temperature, lipoxygenase activity, and fat acidity increased, whereas germination rate was reduced. ER cultivars exhibited the highest lipoxygenase activity of 35.49±2.46 unit/㎎ protein during 24 weeks storage at 25℃, followed by LR (32.73±1.33) and MR (32.66±1.62) cultivars. The amounts of fat acidity also were observed by the same order (ER: 20.40±2.12>LR: 19.68±1.86>MR: 19.64±1.35 ㎎ KOH/100 g). Germination rate slightly decreased with increase of time and temperature (MR>LR>ER), but MR and LR cultivars showed the most significant changes (ER: 60.90±23.47%, MR: 32.66±13.95%, and LR: 32.53±5.87%). On the basis of above results, MR cultivars were evaluated the highest qualit...

Research paper thumbnail of Change in Anthocyanin contents by Cultivation and Harvest Time in Black-Seeded Soybean

The Korean Journal of Crop Science, 2004

The purpose of this experiment was to obtain informations about variation of anthocyanin content ... more The purpose of this experiment was to obtain informations about variation of anthocyanin content within black-seeded soybean testa according to cultivation and harvest time. Three varieties, Ilpumgeomjeongkong, Geomjeongkong 2, Tawonkong were tested in this experiment. Seeds were planted on April 15 (early planting), May 15 (optimum planting), and June 15 (late planting), respectively. Harvest time was R6 (full seed), R7 (physiological maturity), and R8 (harvest maturity), respectively. The content of delphinidin-3-glucoside (D3G), cyanidin-3-glucoside (C3G), petunidin-3-glucoside (Pt3G), and total anthocyanin (TA) had all increased gradually from April 15 to June 15 as well as R6 to R8. There was no varietal difference in D3G, but C3G and TA of Geomjeongkong 2 were higher than other two varieties. Pt3G was the highest Tawonkong of varieties. The value of L as anthocyanin color difference had gradually decreased from April 15 to June 15 and R6 to R8, Geomjeongkong 2 among three vari...

Research paper thumbnail of Optimal Simultaneous Extraction Condition of Caffeine and Catechin Constituents in Green Tea

Research paper thumbnail of Characterization of Anthocyanins in Seed Coats of Kidney Bean (Phaseolus vulgaris L.)

Research paper thumbnail of Preharvest Sprayable 1-Methylcyclopropene (1-MCP) Effects on Fruit Quality Attributes and Cell Wall Metabolism in Cold Stored ‘Fuji’ Apples

Korean Journal of Horticultural Science and Technology, 2018

Research paper thumbnail of Simultaneous Pesticide Analysis Method for Bifenox, Ethalfluralin, Metolachlor, Oxyfluorfen, Pretilachlor, Thenylchlor and Trifluralin Residues in Agricultural Commodities Using GC-ECD/MS

Korean Journal of Environmental Agriculture, 2018

Research paper thumbnail of Analytical Method for Flusulfamide as Benzenesulfonamide Fungicide, Residues in Major Agricultural Commodities

Korean Journal of Environmental Agriculture, 2018

Research paper thumbnail of Isolation and Charaterization of Bioactive Peptides from Hwangtae (yellowish dried Alaska pollack) Protein Hydrolysate

Preventive Nutrition and Food Science, 2008

Research paper thumbnail of Development of Analytical Method for Fipronil Residues in Agricultural Commodities Using GC-ECD/MS

Korean Journal of Environmental Agriculture, 2015

Research paper thumbnail of Determination of Quintozene Residues in Agricultural Commodities Using GC-ECD/MS

The Korean Journal of Pesticide Science, 2015

Research paper thumbnail of Changes of Microclimate Responses and Chlorophyll Content(SPAD) to Different Shading Materials on Korean Ginseng (Panax ginseng C. A. Meyer) Bed

Research paper thumbnail of The Changes of Bioactive Component Concentrations in Different Aged-Peony (Paeonia lactiflora Pall.) Root

This study was conducted to establish the standard of quality evaluation in Korean cultivated peo... more This study was conducted to establish the standard of quality evaluation in Korean cultivated peony root(Paeoniae Radix). The diameter of fresh root and the concentrations of paeoniflorin, abliflorin and five phenolic compounds at different root ages in Euisung cultivar were investigated. The diameters of fresh root were 5.5mm, 10.3mm, 15.6mm and 19.1mm in one-year, two-year, three-year and four-year-old, respectively. It was also found that the diameter of fresh root was uniformly increased with the increase of root age. The concentrations of paeoniflorin, albiflorin, (+) -catechin and benzoic acid in one-year-old peony root(6.44%, 1.55%, 0.80% and 0.36%, respectively) were higher than those in three-(3.49%, 0.62%, 0.43% and 0.26%) or four-year-old(3.28%, 0.47%, 0.34% and 0.20%). The concentrations of gallic acid, (-) -epicatechin and (+) -taxiforin were higher in three- (0.26%, 0.09% and 0.26%, respectively) or four-year-old (0.26%, 0.10% and 0.29%) than those in one-year-old (0.25 %, 0.08 % and 0.23 %) by contraries. Excepting (-) -epicatecin, the concentrations of paeoniflorin, albiflorin and four phenolic compounds in the root of unremoved cork layer were higher than those in the root of removed cork layer.

Research paper thumbnail of Variation of Bioactive Component Contents in Plant Parts of Paeonia lactiflora Pall

Comparative analysis of paeoniflorin, albiflorin and phenolic compound contents as bioactive comp... more Comparative analysis of paeoniflorin, albiflorin and phenolic compound contents as bioactive components of peony was performed by Reverse Phase-High Performance Liquid Chromatography (RPHPLC) using the four- year-old peony which were different plant parts and pretreatment, such as removing or unremoving the cork layer of peony root before drying. The contents of paeoniflorin, albiflorin, (+)-taxifolin , (+)-catechin and (-)-epicatechin were the highest in rhizome part, but those of gallic acid and benzoic acid in the leaves were higher than other parts. The contents of albiflorin, gallic acid, benzoic acid and (-)-epicatechin in the cork layer were higher than in those of the core, but the contents of paeoniflorin, (+)-taxifolin and (+)-catechin in the core were higher than those in the cork layer. In general, the rhizome part of peony root has been used only propagation purpose, but this part contained high contents of bioactive component. Therefore, it is needed that medicinal application of rhizome part in peony root was firmly investigated. Also, In the use of peony root for medicinal purpose, the use of peony root with cork layer can be efficient way on the practical use of useful components and the reduction of labor for removing the cork layer.

Research paper thumbnail of Evaluation of Sesquiterpenoids Content and Growth Characters in Clonal Lines from a Cross between Atractylodes japonica Koidz. ex Kitam. and A. macrocephala Koidz

The Korean Journal of Medicinal Crop Science, 2006

Research paper thumbnail of Development of Forchlorfenuron Residues in Agricultural Commodities Using HPLC-UVD/MS

한국농약과학회 학술발표대회 논문집, Apr 1, 2017

Research paper thumbnail of Evaluation of the Vitamin B Content of Edible Insects

Journal of the Korean Society of Food Science and Nutrition

Research paper thumbnail of The Phenolics and Antioxidant Properties of Black and Purple versus White Eggplant Cultivars

Molecules

The total phenolic content, anthocyanins, phenolic acids, antioxidant capacity and α-amylase inhi... more The total phenolic content, anthocyanins, phenolic acids, antioxidant capacity and α-amylase inhibitory activity of black (Aydin Siyahi), purple (Kadife Kemer) and white (Trabzon Kadife) eggplants grown in Turkey were subjected to a comparative investigation. The black cultivar exhibited the highest total phenolic (17,193 and 6552 mg gallic acid equivalent/kg fw), flavonoid (3019 and 1160 quercetin equivalent/kg fw) and anthocyanin (1686 and 6167 g delphinidin-3-O-glucoside equivalent/kg fw) contents in crude extracts of the peel and pulp. The majority of the caffeic acid was identified in the ester (2830 mg/kg fw) and ester-bound (2594 mg/kg fw) forms in the peel of ‘Kadife Kemer’ and in the glycoside form (611.9 mg/kg fw) in ‘Aydin Siyahi’, as well as in the pulp of these two eggplants. ‘Kadife Kemer’ (purple eggplant) contained the majority of the chlorogenic acid in free form (27.55 mg/kg fw), compared to ‘Aydin Siyahi’ in the ester (7.82 mg/kg fw), glycoside (294.1 mg/kg dw) an...

Research paper thumbnail of Non-destructive Near Infrared Reflectance Spectroscopic Technique for Selecting High Protein and Oil Soybean Lines

Research paper thumbnail of Anthocyanin 함량이 높은 감자 신품종 "자영

`자영`은 2003년 `대서` 품종과 AG34314 계통 간의 교잡후대에서 유래되었으며, 국립식량과학원 고령지농업연구센터의 감자육종 프로그램을 거쳐 선발되었다. 2006년과 ... more `자영`은 2003년 `대서` 품종과 AG34314 계통 간의 교잡후대에서 유래되었으며, 국립식량과학원 고령지농업연구센터의 감자육종 프로그램을 거쳐 선발되었다. 2006년과 2007년 대관1-104호라는 계통명으로 지역적응시험을 수행하여 주요생육특성, 괴경특성, 수량성 및 병해특성을 검토하였으며, 2007년 `자영`으로 명명하여 국립종자관리원에 신품종으로 출원하였다. `자영` 감자는 모양이 비교적 둥글고 눈이 얕으며 껍질과 속이 모두 자주색이다. ha당 평균 수량은 37.4톤이었고 봄재배에서 가장 높은 수량성을 나타냈다. `자영`은 감자더뎅이병과 잎말림바이러스병에 높은 저항성을 나타내었으나, 역병에는 감수성이었다. 건물함량은 비교적 높은 20.3%로서 칩가공용으로도 적합하였다. 안토시아닌 함량은 가을재배에서 가장 높은 43.7 mg/100 g이었고, 작형별 평균 함량은 `자심` 품종보다 4.7배 정도 더 많았다.

Research paper thumbnail of Characterization of Soybean Isoflavones Using LC/ES-MS

Research paper thumbnail of Characteristic Changes in Brown Rice (Oryza sativa L.) Cultivars of 3 Ecotypes During Different Storage Conditions

Food Science and Biotechnology, 2009

The aim of this study investigated the fluctuations of 3 characters from 3 ecotypes [early ripeni... more The aim of this study investigated the fluctuations of 3 characters from 3 ecotypes [early ripening (ER), middle ripening (MR), and late ripening (LR)] of 20 Korean brown rice cultivars in different storage systems [time: 12 and 24 weeks, temperature: low (10℃) and room (25℃)]. With increase of storage time and temperature, lipoxygenase activity, and fat acidity increased, whereas germination rate was reduced. ER cultivars exhibited the highest lipoxygenase activity of 35.49±2.46 unit/㎎ protein during 24 weeks storage at 25℃, followed by LR (32.73±1.33) and MR (32.66±1.62) cultivars. The amounts of fat acidity also were observed by the same order (ER: 20.40±2.12>LR: 19.68±1.86>MR: 19.64±1.35 ㎎ KOH/100 g). Germination rate slightly decreased with increase of time and temperature (MR>LR>ER), but MR and LR cultivars showed the most significant changes (ER: 60.90±23.47%, MR: 32.66±13.95%, and LR: 32.53±5.87%). On the basis of above results, MR cultivars were evaluated the highest qualit...

Research paper thumbnail of Change in Anthocyanin contents by Cultivation and Harvest Time in Black-Seeded Soybean

The Korean Journal of Crop Science, 2004

The purpose of this experiment was to obtain informations about variation of anthocyanin content ... more The purpose of this experiment was to obtain informations about variation of anthocyanin content within black-seeded soybean testa according to cultivation and harvest time. Three varieties, Ilpumgeomjeongkong, Geomjeongkong 2, Tawonkong were tested in this experiment. Seeds were planted on April 15 (early planting), May 15 (optimum planting), and June 15 (late planting), respectively. Harvest time was R6 (full seed), R7 (physiological maturity), and R8 (harvest maturity), respectively. The content of delphinidin-3-glucoside (D3G), cyanidin-3-glucoside (C3G), petunidin-3-glucoside (Pt3G), and total anthocyanin (TA) had all increased gradually from April 15 to June 15 as well as R6 to R8. There was no varietal difference in D3G, but C3G and TA of Geomjeongkong 2 were higher than other two varieties. Pt3G was the highest Tawonkong of varieties. The value of L as anthocyanin color difference had gradually decreased from April 15 to June 15 and R6 to R8, Geomjeongkong 2 among three vari...

Research paper thumbnail of Optimal Simultaneous Extraction Condition of Caffeine and Catechin Constituents in Green Tea

Research paper thumbnail of Characterization of Anthocyanins in Seed Coats of Kidney Bean (Phaseolus vulgaris L.)

Research paper thumbnail of Preharvest Sprayable 1-Methylcyclopropene (1-MCP) Effects on Fruit Quality Attributes and Cell Wall Metabolism in Cold Stored ‘Fuji’ Apples

Korean Journal of Horticultural Science and Technology, 2018

Research paper thumbnail of Simultaneous Pesticide Analysis Method for Bifenox, Ethalfluralin, Metolachlor, Oxyfluorfen, Pretilachlor, Thenylchlor and Trifluralin Residues in Agricultural Commodities Using GC-ECD/MS

Korean Journal of Environmental Agriculture, 2018

Research paper thumbnail of Analytical Method for Flusulfamide as Benzenesulfonamide Fungicide, Residues in Major Agricultural Commodities

Korean Journal of Environmental Agriculture, 2018

Research paper thumbnail of Isolation and Charaterization of Bioactive Peptides from Hwangtae (yellowish dried Alaska pollack) Protein Hydrolysate

Preventive Nutrition and Food Science, 2008

Research paper thumbnail of Development of Analytical Method for Fipronil Residues in Agricultural Commodities Using GC-ECD/MS

Korean Journal of Environmental Agriculture, 2015

Research paper thumbnail of Determination of Quintozene Residues in Agricultural Commodities Using GC-ECD/MS

The Korean Journal of Pesticide Science, 2015

Research paper thumbnail of Changes of Microclimate Responses and Chlorophyll Content(SPAD) to Different Shading Materials on Korean Ginseng (Panax ginseng C. A. Meyer) Bed

Research paper thumbnail of The Changes of Bioactive Component Concentrations in Different Aged-Peony (Paeonia lactiflora Pall.) Root

This study was conducted to establish the standard of quality evaluation in Korean cultivated peo... more This study was conducted to establish the standard of quality evaluation in Korean cultivated peony root(Paeoniae Radix). The diameter of fresh root and the concentrations of paeoniflorin, abliflorin and five phenolic compounds at different root ages in Euisung cultivar were investigated. The diameters of fresh root were 5.5mm, 10.3mm, 15.6mm and 19.1mm in one-year, two-year, three-year and four-year-old, respectively. It was also found that the diameter of fresh root was uniformly increased with the increase of root age. The concentrations of paeoniflorin, albiflorin, (+) -catechin and benzoic acid in one-year-old peony root(6.44%, 1.55%, 0.80% and 0.36%, respectively) were higher than those in three-(3.49%, 0.62%, 0.43% and 0.26%) or four-year-old(3.28%, 0.47%, 0.34% and 0.20%). The concentrations of gallic acid, (-) -epicatechin and (+) -taxiforin were higher in three- (0.26%, 0.09% and 0.26%, respectively) or four-year-old (0.26%, 0.10% and 0.29%) than those in one-year-old (0.25 %, 0.08 % and 0.23 %) by contraries. Excepting (-) -epicatecin, the concentrations of paeoniflorin, albiflorin and four phenolic compounds in the root of unremoved cork layer were higher than those in the root of removed cork layer.

Research paper thumbnail of Variation of Bioactive Component Contents in Plant Parts of Paeonia lactiflora Pall

Comparative analysis of paeoniflorin, albiflorin and phenolic compound contents as bioactive comp... more Comparative analysis of paeoniflorin, albiflorin and phenolic compound contents as bioactive components of peony was performed by Reverse Phase-High Performance Liquid Chromatography (RPHPLC) using the four- year-old peony which were different plant parts and pretreatment, such as removing or unremoving the cork layer of peony root before drying. The contents of paeoniflorin, albiflorin, (+)-taxifolin , (+)-catechin and (-)-epicatechin were the highest in rhizome part, but those of gallic acid and benzoic acid in the leaves were higher than other parts. The contents of albiflorin, gallic acid, benzoic acid and (-)-epicatechin in the cork layer were higher than in those of the core, but the contents of paeoniflorin, (+)-taxifolin and (+)-catechin in the core were higher than those in the cork layer. In general, the rhizome part of peony root has been used only propagation purpose, but this part contained high contents of bioactive component. Therefore, it is needed that medicinal application of rhizome part in peony root was firmly investigated. Also, In the use of peony root for medicinal purpose, the use of peony root with cork layer can be efficient way on the practical use of useful components and the reduction of labor for removing the cork layer.