• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.844-847
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• 2001

Factors affecting thermostability of polyphenol oxidase (PPO) from potato were studied for the purpose of providing useful information for food processing operations. The enzyme was most stable at pH 7.0 and it was inhibited to 70% after heat treatment at 8$0^{\circ}C$ for 1 min. The z-value for the thermal inactivation of the PPO was 12.17$\pm$0.58$^{\circ}C$. The thermostability of the enzyme was reduced by addition of sodium chloride. And the activity was inhibited by addition of reducing reagents such as 2-mercaptoethanol and dithiothreitol.

• Journal of Plant Biotechnology
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• v.1 no.2
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• pp.85-90
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• 1999

In order to protect fungal diseases, leaf disc explants of Solanum tuberosum cultivar, Belchip, was infected with an Agrobacterium MP90 strain containing chimeric gene construct, consisting of antibiotic resistance and chitinase gene driven by the CaMV 35S promoter, for transformation. Regenerated multiple shoots were selected on a medium containing kanamycin and carbenicillin after exposure to Agrobacterium. The presence and integration of the npt II and chitinase gene were confirmed by polymerase chain reaction(PCR). Northern blot analysis indicated that the genes coding for the enzyme could be expressed in potato plants. The chitinase activity of transgenic potato plants was higher than the control potato.

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2529-2532
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• 2014

• Korean Journal of Plant Tissue Culture
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• v.27 no.1
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• pp.39-45
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• 2000

Two maize transposable elements, immobilized Ac (iAc) and Ds, have been introduced into the genome of a diploid potato clone (Solanum tuberosum Group Phureja clone 1.22). The iAc is a modified Ac that is supposed to be unable to transpose but is expected to trans-activate the transposition of a Ds that is unable to transpose by itself. When the leaf and stem explants of in vitro shoots of the clone 1.22 were inoculated with Agrobacterium tumefaciens strains harboring binary vectors containing the iAc and the Ds, calli were formed from the explants on media containing 50 mg/L of kanamycin, and shoots were regenerated from the calli. The regenerated shoots formed roots when cultured on media containing 100 mg/L of kanamycin, whereas untransformed shoots did not form roots on the same media. The PCR amplification of the DNA's from the transgenic plants confirmed that the iAc and the Ds elements were introduced into the potato genome of 1.22.

• Proceedings of the Korean Nuclear Society Conference
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• 2002.05a
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• pp.427.2-427
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• 2002

• Proceedings of the Korean Society of Crop Science Conference
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• 2020.11a
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• pp.90-90
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• 2020

• Journal of Plant Biology
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• v.39 no.2
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• pp.93-98
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• 1996

In order to enhance the system of potato transformation and further regeneration, potato was transformed using the Agrobacterium tumefaciens harboring $\beta$-glucuronidase (GUS) gene. We found that a series fo modified medium ttained 100% shoot regeneration within 5 weeks after the preincubated explants on stage I medium were infected with Agrobacterium. Callus appeared at the cut edges of stem segments on stage II medium, mainly at the basal parts. Some explants started to form shoots after two to three weeks on stage III medium containing kanamycin (50 mg/L). When transferred to MS medium containing 200 mg/L kanamycin, 81% of the transformed shoots formed roots at the cut edge of the plantlets. In contrast, untrasformed shoots never rooted and became yellowish after few weeks under the same conditions. Southern and northern analysis indicated in vitro shoot regeneration on the callus derived from the potato explants, which were incubated with Agrobacteria. The regeneration cycle was shortened after the transformatin and finally the transformation efficiency was highly enhanced.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.385-390
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• 2009

A resveratrol synthase (RS) gene was isolated from peanut (Arachis hypogaea, L. cv. Jinpoong) plants. This gene was placed under the control of the cauliflower mosaic virus 35S promoter (CaMV35S) and introduced into two Korean varieties of potato (Solanum tuberosum L. cvs. Jasim and Jowon) plants by Agrobacterium-mediated gene transfer. Putative transformants were screened by PCR with primers designed from CaMV 35S promoter, NOS terminator and RS gene. Most of selected transgenic potato plants showed the amplification of expected fragments by PCR of genomic DNA with gene-specific primers, while they were absent in untransformed control plants. Expression of the resveratrol synthase gene was also examined by northern blot analysis. The transformants showed a band which was lacking in the control plant, confirming that the introduced gene is transcribed into mRNA in the transformants. The strength of the band, which reflected the level of mRNA expression, differed among the individual transformants. Among the transformants obtained, the highest trans-resveratrol content in the transgenic young leaves of purple-fleshed "Jashim" was $2.11{\mu}gg^{-1}$ fresh weight and that in the microtubers in vitro of purple fleshed "Jashim" was $8.31{\mu}gg^{-1}$ fresh weight. This amount of resveratrol may have a positive biological effect on human health.

• Plant Disease and Agriculture
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• v.5 no.1
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• pp.64-66
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• 1999

Black leg occurred in potato (Solanum tuberosum L.) grown in Pyungchang, Kangwon-Do, Korea. The symptoms began as small water-soaked lesions on stem, and the affected stems discolored black to brown. It became yellow under dry condition. When lower parts of potato were affected in the field, wilting of leaves and desiccation of the stem were developed. The causal organism was isolated from lesions and identified as Erwinia carotovora subsp. atroseptica based on the morphological, physiological and biochemical characteristics. E. carotovora subsp. atroseptica is the first described bacterium which causes black leg in potato in Korea.

• Journal of Plant Biotechnology
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• v.42 no.2
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• pp.77-82
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• 2015

We found that a long period of in vitro culture is a critical factor on the low transformation rate for a specific potato genotype, Solanum tuberosum L. var. Atlantic when phosphinothricin (PPT) was added to select putative transformants in a solid media. The fresh explants of the newly produced plants from a micro-tuber was able to increase the transformation rate significantly while the old explants prepared from a plant maintained for longer than 6 months in vitro by sub-culturing every 3 ~ 4 weeks resulted in a very low transformation frequency. However, Jowon cultivar was not so much influenced by the period of in vitro culture with high transformation rate (higher than 10.0%). Further research need to be explored for the reason why a particular potato genotype, Atlantic is more vulnerable than the Jowon cultivar during the regeneration stage resulting in the low transformation frequency.