• Proceedings of the Korean Society of Crop Science Conference
• /
• 2018.10a
• /
• pp.42-42
• /
• 2018

Anthocyanins has a strong antioxidant capacity but exhibit poor stability in water. Therefore, stability of anthocyanin from purple potato (Solanum tuberosum L.) was encapsulated by the application of food polymers. Solid formulation of purple potato was prepared using whey protein, tapioca and lecithin by capillary rheometer at $80^{\circ}C$. The ratio of the polymer and potato powder was 2:8. Total phenolic compound, total flavonoid, total anthocyanin and antioxidant activity was investigated by the spectrophotometer. Result revealed that total phenolic compound (TP) ($5321{\mu}g/100g$), total flavonoid (TF) ($1352{\mu}g/100g$) total anthocyanin (TA) ($764{\mu}g/100g$) and free radical antioxidant activity (DPPH) (86%) was higher in 0.01 M acetic acid mediated lecithin based formulation compared to control (Potato powder) (TP: $1357{\mu}g/100g$; TF) ($634{\mu}g/100g$, TA) ($264{\mu}g/100g\;DPPH$) (64%). Lecithin is a strong emulsifier having capacity to extract bioactive compound and encapsulate extracted compound by nonpolar tail and negatively charged head. Therefore, it would be concluded that lecithin might be used as an encapsulating agent for the bioactive compound from purple potato.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2018.10a
• /
• pp.274-274
• /
• 2018

Anthocyanins has a strong antioxidant capacity but exhibit poor stability in water. Therefore, stability of anthocyanin from purple potato (Solanum tuberosum L.) was encapsulated by the application of food polymers. Solid formulation of purple potato was prepared using whey protein, tapioca and lecithin by capillary rheometer at $80^{\circ}C$. The ratio of the polymer and potato powder was 2:8. Total phenolic compound, total flavonoid, total anthocyanin and antioxidant activity was investigated by the spectrophotometer. Result revealed that total phenolic compound (TP) ($5321{\mu}g/100g$), total flavonoid (TF) ($1352{\mu}g/100g$) total anthocyanin (TA) ($764{\mu}g/100g$) and free radical antioxidant activity (DPPH) (86%) was higher in 0.01 M acetic acid mediated lecithin based formulation compared to control (Potato powder) (TP: $1357{\mu}g/100g$; TF) ($634{\mu}g/100g$, TA) ($264{\mu}g/100g\;DPPH$) (64%). Lecithin is a strong emulsifier having capacity to extract bioactive compound and encapsulate extracted compound by nonpolar tail and negatively charged head. Therefore, it would be concluded that lecithin might be used as an encapsulating agent for the bioactive compound from purple potato.

• Journal of Plant Biotechnology
• /
• v.37 no.1
• /
• pp.110-114
• /
• 2010

Highest increase of biomass was observed when tissue-cultured potato (Solanum tuberosum L. cv. Chubaek) shoots were cultured in a liquid medium containing 1/3 MS solution in a 18 L bioreactor, as compared to 1/4 and 1/2 MS solution. The medium containing 1/4 MS solution showed higher increase of shoot biomass than one containing 1/2 MS solution. Potato microtubers were formed when the medium was exchanged with the medium for microtuber formation and incubated under dark condition. The microtubers were observed first at some axillary buds one week after incubation under dark condition and then at most of the axillary buds by the end of 3 weeks. The 1.5 MS liquid medium and $20^{\circ}C$ were optimal conditions. By the end of 6 weeks, more 1,000 microtubers were formed in the 18 L bioreactor. Then, greened microtubers were harvested after one week culture under light condition.

• Journal of Plant Biotechnology
• /
• v.37 no.1
• /
• pp.89-95
• /
• 2010

Dihydroflavonol 4-reductase (DFR) is a key enzyme of the flavonoid biosynthesis pathway which catalyses the NADPH-dependent reduction of 2R,3R-trans-dihydroflavonols to leucoanthocyanidins. In this study we describe cloning and expression of the genes encoding the flavonoid-biosynthetic enzyme DFR in Gypsophila paniculata L. Inspection of the 1279 bp long sequence revealed an open reading frame 1063 bp, including a 36 bp 5' leader region and 181 bp 3' untranslated region. Comparison of the coding region of this DFR cDNA sequence including the sequences of Arabidopsis thaliana, Citrus sinensis, Dianthus caryophyllus, Ipomoea batatas, Matthiola incana, Nierembergia sp, Petunia hybrida, Solanum tuberosum, Vitis vinifera reveals an identity higher than 69% at the nucleotide level. The function of this nucleotide sequences was verified by comparison with amino acid sequences of the amino-terminus and tryptic peptides from purified plant enzyme, by northern blotting with mRNA from wild type and mutant plants, by in vitro expression yielding and enzymatically active reductase, as indicated by the small leucopelargonidin peak. Genomic southern blot analysis showed the presence of only one gene for DFR in Gypsophila paniculata.

• Food Science and Biotechnology
• /
• v.18 no.1
• /
• pp.113-117
• /
• 2009

A method was developed using enhanced liquid chromatography coupled with electrospray ionization mass spectrometry for the analysis and quantitation of 2 main potato glycoalkaloids, $\alpha$-chaconine, and $\alpha$-solanine, without any pre-concentration or derivatisation steps. Calibration curves generated by this technique exhibited a linear dynamic range from 0.025 to $50{\mu}g/mL$ and from 0.05 to $50{\mu}g/mL$ for $\alpha$-chaconine and $\alpha$-solanine, respectively. Matrix effects were evaluated by comparing calibration curves measured in matrix-matched and solvent-based systems. Ion suppression due to matrix effects was weak and extraction recoveries of 88 to 114% were obtained in different sample matrices spiked with analyte concentrations ranging from 15 to $35{\mu}g/mL$. Potatoes that had been genetically modified to tolerate glufosinate contained the same glycoalkaloid levels as their non-transgenic counterpart. We suggest complementing compositional comparison assessment strategy by validating quantitative analytical methods for the toxic glycoalkaloids in potato plants.

• Horticultural Science & Technology
• /
• v.31 no.1
• /
• pp.24-31
• /
• 2013

This study was conducted to determine the characteristics of quality and yield in potatoes grown at paddy field before rice transplantation during the spring season. Three potato cultivars ('Jowon', 'Haryeong', and 'Goun') were grown in Gangneung (asl 5 m) and Seocheon (asl 20 m). In both locations, weather condition belonged to the fourth zone (spring cropping) in potato production location's distribution of Korea. Daily mean soil temperature in both the locations was $0.2-0.6^{\circ}C$ lower than air temperature, while soil moisture was adequate level to potato growth in spite of spring drought. TR ratio was not affected by location, but by cultivar. Specific gravity, starch content, dry matter rate, and yield were significantly influenced by location and by cultivar. There was no difference in total tuber number by location, however there was a large gap in marketable tuber yield according to locations and cultivars. There were high negative relationships between yield and main qualities such as dry matter rate and starch content, while high positive correlation was observed between main qualities. It was possible to produce potato before rice transplanting at drained paddy fields located in representative two locations of potato spring cropping and their characteristics in growth and quality were similar to those generally well known in upland cultivation. Paddy field was thought to be more favorable than upland in terms of available soil moisture supply against spring drought. Further research, however, was needed to increase soil temperature and also preliminary review on proper cultivar according to location seemed to be needed for high yield.

• Korean Journal of Soil Science and Fertilizer
• /
• v.46 no.6
• /
• pp.463-468
• /
• 2013

The level of nitrous oxide ($N_2O$), a long-lived greenhouse gas, in atmosphere has increased mainly due to anthropogenic source, especially application of nitrogen fertilizers. Quantifying $N_2O$ emission from agricultural field is essential to develop national inventories of greenhouse gases (GHGs) emission. The objective of the study was to develop emission factor to estimate direct $N_2O$ emission from agricultural field in Gangwon-do, Korea by measuring $N_2O$ emissions from potato (Solanum tuberosum), red pepper (Capsicum annum L.), and Chinese cabbage (Brassica campestris L.) cultivation lands from 2009 to 2012. Accumulated $N_2O$ emission was $1.48{\pm}0.25kg$ $N_2O-N\;ha^{-1}$ for red pepper, $1.27{\pm}0.27kg$ $N_2O-N\;ha^{-1}$ for potato, $1.49{\pm}0.06kg$ $N_2O-N\;ha^{-1}$ for Chinese cabbage cultivated in spring, and $1.14{\pm}0.22kg$ $N_2O-N\;ha^{-1}$ for fall Chinese cabbage. Emission factor of $N_2O$ calculated from accumulated $N_2O$ emission, nitrogen fertilization rate, and background $N_2O$ emission was $0.0051{\pm}0.0016kg$ $N_2O-N\;ha^{-1}$ N for cropland in Gangwon province. More extensive study is deserved to be conducted to develop $N_2O$ emission factor for upland crops in Korea through examining the emission factors from various regions and crops because $N_2O$ emission is influenced by many factors including climate characteristics, soil properties, and agricultural practices.

• Preventive Nutrition and Food Science
• /
• v.21 no.2
• /
• pp.110-116
• /
• 2016

This study was performed to evaluate and compare the antioxidant substance content and antioxidant activities of white (Superior) and colored (Hongyoung, Jayoung, Jasim, Seohong, and Jaseo) potatoes. The potatoes were extracted with 80% ethanol and were evaluated for the total polyphenol, flavonoid, and anthocyanin contents and for 1,1-diphenyl-2-picrylhydrazyl (DPPH)/2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity, reducing power, and ferrous metal ion chelating effect. The total polyphenol, flavonoid, and anthocyanin contents of Hongyoung and Jayoung were higher than white and other colored potatoes. All colored potato extracts, except for Jaseo and Seohong, showed higher ABTS radical scavenging activities than the general white potato extract. Hongyoung and Jayoung had the highest ABTS and DPPH radical scavenging activities. Optical density values for the reducing power of Jayoung and Jaseo at concentration of 2 mg/mL were 0.148 and 0.090, respectively. All colored potato extracts had lower ferrous metal ion chelating effect than the white potato. A significant (P<0.05) positive correlation was observed between total polyphenol content and total flavonoid content (r=0.919), anthocyanin content (r=0.992), and ABTS radical scavenging activity (r=0.897). Based on these results, this research may be useful in developing the Hongyoung and Jayoung cultivars with high antioxidant activities.

• Korean Journal of Soil Science and Fertilizer
• /
• v.49 no.5
• /
• pp.548-554
• /
• 2016

Optimal range of soil physical quality to enhance crop productivity or to improve environmental health is still in dispute for the upland soil. We hypothesized that the optimal range might be established by comparing soil physical parameters and their interactions inhibiting crop growth. The parameter identifying optimal range covered favorable conditions of aeration, permeability and root extension. To establish soil physical standard two experiments were conducted as follows; 1) investigating interactions of bulk density and aeration porosity in the laboratory test and 2) determining effects of soil compaction and deep & conventional tillage on physical properties and crop growth in the field test. The crops were Perilla frutescens, Zea mays L., Solanum tuberosum L. and Secale cereael. The saturated hydraulic conductivity, bulk density from the root depth, root growth and stem length were obtained. Higher bulk density showed lower aeration porosity and hydraulic conductivity, and finer texture had lower threshold bulk density at 10% aeration bulk density. Reduced crop growth by subsoil compaction was higher in silt clay loam compared to other textures. Loam soil had better physical improvement in deep rotary tillage plot. Combined with results of the present studies, the soil physical quality was possibly assessed by bulk density index. Threshold subsoil bulk density as the upper value were $1.55Mg\;m^{-3}$ in sandy loam, $1.50Mg\;m^{-3}$ in loam and $1.45Mg\;m^{-3}$ in silty clay loam for optimal soil physical quality in upland.

• Horticultural Science & Technology
• /
• v.19 no.4
• /
• pp.459-464
• /
• 2001

Leaf disks from cultivar 'Kennebec' and one selection line (ND 860-2) were cultured on Murashige-Skoog medium with various combinations of indole acetic acid (IAA) and zeatin riboside. Shoots, roots and callus were induced at various combinations of plant growth regulator levels. The medium containing $3.5mg{\cdot}L^{-1}$ IAA and $4.0mg{\cdot}L^{-1}$ zeatin riboside produced the most plantlets. Rooted regenerants were grown in the greenhouse. The growth of regenerated plants obtained from the MS medium supplemented with $7.0mg{\cdot}L^{-1}$ IAA and $3.0mg{\cdot}L^{-1}$ zeatin riboside was significantly greater than those grown from nodal expalnts. In ND 860-2, a leaf chimera with chlorophyll deficient (light yellow) sectors was found in plants regenerated fiom leaf disks (grown on MS medium supplemented with $3.5mg{\cdot}L^{-1}$ IAA and $3.0mg{\cdot}L^{-1}$ zeatin riboside) but not in plants grown from nodal explants. The phenotypic variability was also observed in the tuber number, size and weight.