• Journal of the Korean Home Economics Association
• /
• v.42 no.4
• /
• pp.187-194
• /
• 2004

The concentration of potato(Solanum tuberosum L.) glycoalkaloids(PCA) (i.e., ${\alpha}$-chaconine and ${\alpha}$-solanine) in Korean cultivated potato plant, and in the different varieties, parts and weights of the potato tubers, were determined by high-performance liquid chromatography(HPLC). The highest concentrations of PGA in potato plants were found in the roots, followed by the stems and leaves. A large quantity of PGA existed in the periderm of 'Atlantic' potatoes, whereas 'Irish Cobbler' contained the lowest amount in five cultivated potato tubers.'Irish Cobbler' potatoes were divided into three parts and the PGA content in each part was determined. It was found that both of the end parts of the potatoes contained higher PGA than the middle part. The PGA contents in four different sizes of potatoes increased toward the smaller size. Thesignificantly high level of PGA was contained in the smallest size potato tubers, which have been used widely for Korean cooking.

• Natural Product Sciences
• /
• v.15 no.3
• /
• pp.134-138
• /
• 2009

In an attempt to establish anti-ulcerogenic activity of potato tubers, inhibitory activity against ethanol- and indomethacin-induced gastric ulcer models in rats was evaluated for the first time. From several varieties of potato tubers including Solanum tuberosum L. cv. Superior (white skin and fresh potato) and two new varieties of (Bora valley and Gogu valley), raw potato juice was prepared and the starch was obtained from each juice by filtration and drying. Upon oral administration to rats, raw potato juice showed more or less inhibitory activity. The starch showed higher and dose-dependent inhibitory activity, suggesting that the active ingredient in raw potato juice may be the starch. Particularly, the starch obtained from the tubers of new potato variety, "Bora valley," with purple color, showed the highest inhibitory activity (62.4% and 37.1% inhibition of ulcer index at 500 mg/kg), while omeprazole (proton pump inhibitor) used as a reference drug showed 74.4% and 75.7% inhibition at 20 mg/kg against ethanol- and indomethacin-induced ulcer formation, respectively. The present study provides a first evidence of anti-ulcerogenicity of raw potato juice and the starch. Especially, the starch from "Bora valley" strongly inhibited ulcer formation in rats. Considering that these are food components, they may be safely used for anti-ulcerogenic nutraceuticals.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.47
• /
• pp.135-139
• /
• 2002

The standard of quality was required to promote the consumption of potato and produce the high quality processing products. It will contribute the stability for processing products and the marketability of potato. The quality was determined based on size of tuber and content of dry matter. Even though the criteria of potato quality was involved many characters of tubers, the most important things were grading and packing of potato to create the consumption. For processing of raw materials, the standard of tubers had create between producer and processor according to size of tuber and content of dry matter. The evaluation of quality was performed over the standard to enhance the control of quality. In addition, the seed potato should be taken the evaluation to disease in the field during the period of cultivation and managed under the strict regulation in storage before release to farmer. Then, the producer of seed potato will make a good relationship to farmer with high quality tubers.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2010.10a
• /
• pp.14-14
• /
• 2010

Vitamin C (ascorbic acid) is an essential component for collagen biosynthesis and also for the proper functioning of the cardiovascular system in humans. Unlike most of the animals, humans lack the ability to synthesize ascorbic acid on their own due to a mutation in the gene encoding the last enzyme of ascorbate biosynthesis. As a result, vitamin C must be obtained from dietary sources like plants. In this study, we have developed two different kinds of transgenic potato plants (Solanumtuberosum L. cv. Taedong Valley) overexpressing strawberry GalUR and mouse GLoase gene under the control of CaMV 35S promoter with increased ascorbic acid levels. Integration of the these genes in the plant genome was confirmed by PCR and Southern blotting. Ascorbic acid(AsA) levels in transgenic tubers were determined by high-performance liquid chromatography(HPLC). The over-expression of these genes resulted in 2-4 folds increase in AsA intransgenic potato and the levels of AsA were positively correlated with increased geneactivity. The transgenic lines with enhanced vitamin C content showed enhanced tolerance to abiotic stresses induced by methyl viologen(MV), NaCl or mannitol as compared to untransformed control plants. The leaf disc senescence assay showed better tolerance in transgenic lines by retaining higher chlorophyll as compared to the untransformed control plants. Present study demonstrated that the over-expression of these gene enhanced the level of AsA in potato tubers and these transgenics performed better under different abiotic stresses as compared to untransformed control. We have also investigated the mechanism of the abiotic stress tolerance upon enhancing the level of the ascorbate in transgenic potato. The transgenic potato plants overexpressing GalUR gene with enhanced accumulation of ascorbate were investigated to analyze the antioxidants activity of enzymes involved in the ascorbate-glutathione cycle and their tolerance mechanism against different abiotic stresses under invitro conditions. Transformed potato tubers subjected to various abiotic stresses induced by methyl viologen, sodium chloride and zinc chloride showed significant increase in the activities of superoxide dismutase(SOD, EC 1.15.1.1), catalase, enzymes of ascorbate-glutathione cycle enzymes such as ascorbate peroxidase(APX, EC 1.11.1.11), dehydroascorbate reductase(DHAR, EC 1.8.5.1), and glutathione reductase(GR, EC 1.8.1.7) as well as the levels of ascorbate, GSH and proline when compared to the untransformed tubers. The increased enzyme activities correlated with their mRNA transcript accumulation in the stressed transgenic tubers. Pronounced differences in redox status were also observed in stressed transgenic potato tubers that showed more tolerance to abiotic stresses when compared to untransformed tubers. From the present study, it is evident that improved to lerance against abiotic stresses in transgenic tubers is due to the increased activity of enzymes involved in the antioxidant system together with enhanced ascorbate accumulated in transformed tubers when compared to untransformed tubers. At moment we also investigating the role of enhanced reduced glutathione level for the maintenance of the methylglyoxal level as it is evident that methylglyoxal is a potent cytotoxic compound produced under the abiotic stress and the maintenance of the methylglyoxal level is important to survive the plant under stress conditions.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.46 no.2
• /
• pp.121-124
• /
• 2001

Potato (Solanum tuberosum L.) tubers of 10, 20, 30, 40, and 50 g were planted in plug trays with vermiculite-based root medium on 10 August 2000 and grown for 15 days in a glasshouse to determine the effects of mini-tuber size on plug seedling growth and field performance of plug seedlings. For a control, common potato tubers weighing 50 g were also planted. As size of seed tubers planted increased from 10 to 50 g, seedling height decreased from 24.6 to 20.0cm while shoot number per seedling increased from 2.0 to 3.5, main stem diameter from 4.3 to 6.1mm, and fresh weight of root + top from 9.3 to 19.4 g/seedling. At 90 days after transplanting plug seedlings, the total number of tubers per plant increased from 3.62 to 4.72, average tuber weight from 62.9 to 72.8g, and total tuber yield 20.5 to 23.6 t/ha with increase in seed tuber size. Plug seedlings raised from 50g tubers produced 22% more tubers per plant and had 21 % higher＞80g tuber yield than the directly planted potatoes.

• Journal of Plant Biology
• /
• v.30 no.4
• /
• pp.287-298
• /
• 1987

The regenerative capacities of protoplasts isolated from potato (Solamum tuberosum L.) tubers and tobacco (Nicotiana tabacum L.) mesophyll tissues were examined, and then their intergeneric protoplast fusion was carried out. The potato tuber-derived protoplasts proliferated into the calli some of which showed rudimentary shoot-like structures, which had not been attempted before from tubers, while the tobacco protoplasts were regenerated into the whole plants. Intergeneric protoplast fusion between potato and tobacco was carried out and the heteroplasmic fusion products were formed. The first cell division of some of them was observed after 5 days of culture.

• Korean Journal of Food Science and Technology
• /
• v.7 no.3
• /
• pp.159-167
• /
• 1975

Present work was conducted to investigate the combined effects of gamma-radiation and chemical treatment on the inhibition of sprouting and decay of potato tubers. Irish Cobbler, Apollo and Shimabara potato tubers were immersed in 1000, 2000 and 3000 ppm solution of salicylic acid for 2 minutes, and then irradiated at doses of 5, 10, and 15 krad using an indoor gamma room of approximately 10,000 Ci of $^{60}Co$. Treated tubers were stored for 8 months at room temperature. The results of this work are summarized as follows: 1. Moisture content of irradiated potato tubers was changed less than the control, and decreased gradually along with an extended storage period. Ascorbic acid content was remarkably decreased by gamma-radiation and an extended storage period. 2. Reducing sugar content of irradiated potato tubers tended to increase greatly compared with unirradiated potato tubers, however, starch content of irradiated potato tubers decreased compared with the control. Reducing sugar and starch content of all groups also decreased gradually along with an extended storage period. 3. The storageability of Irish Cobbler variety was best among three varieties and Shimabara variety was worst among them when gamma-radiation is treated singly or in combination with the chemical. Sprouting of potato tubers was more suppressed in combination treatment than single treatment. 4. Decay of potato tubers was more reduced in combination treatment than single treatment. Chemical treatment or gamma-radiation followed by chemical treatment had no influence on decay or spronting of potato tubers. 5. Weight loss of potato tubers was considerably increased as storage period became extended. Shrinkage was, more serious in Shimabara than in rish Cobbler.

• Korean Journal of Food Science and Technology
• /
• v.4 no.1
• /
• pp.29-35
• /
• 1972

Effects of various dosages of gamma ray ranging from 0 to 16 krad on sprout inhibition and nutritive value of potato tubers were investigated with Irish Cobbler variety. Sprout growth was gradually suppressed with increasing dosage, and completely inhibited with 16 krad treatment. Under this optimum dosage, weight loss of tubers was markedly reduced and tubers kept firm throughout the 2 month storage period. Irradiation had no adverse effects on the cooking quality of potato tubers. Moisture content of stored potato tubers was shown to be in inverse proportion to sprout growth. Tubers treated with 16 krad tended to contain somewhat higher percentage of total carbohydrate than those treated with lower dosages. Significantly larger amounts of ascorbic acid were retained in 8 and 16 krad treatments than in 0 and 2 krad treatments.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.60 no.2
• /
• pp.231-238
• /
• 2015

This study was carried out to determine environmental factors affecting the anthocyanin content of color-fleshed potato (Solanum tuberosum L.) tubers. After planting of two color-fleshed potato cultivars of 'Hongyoung' and 'Jayoung' in different 14 locations, their soil chemical properties and meteorological data were evaluated, and anthocyanin contents of tubers were analyzed after harvest, additionally their relationship among them was analyzed through correlation analysis. In comparison with two cultivars, purple-fleshed 'Jayoung' potatoes showed higher anthocyanin content than red-fleshed 'Hongyoung' in almost locations. When locations were divided to three categories (highland, sub-highland and lowland) according to altitude, in general, highland-grown tubers had the higher content of anthocyanin compared to those grown in lowland. An analysis of the results of chemical components of soil showed that anthocyanin content of color-fleshed potato tubers was negatively correlated with the pH of soil. In addition, mean temperature and minimum temperature from 80 to 100 days after planting most significantly affected on the accumulation of anthocyanin in color-fleshed potato tubers, that is, higher content of anthocyanin was observed in tubers produced in locations with lower mean temperature and minimum temperature from 80 to 100 days after planting. This information can be useful to producers and industries in selection of proper fields for the production of color-fleshed potato tubers having high quality in Korea.

• Applied Chemistry for Engineering
• /
• v.24 no.5
• /
• pp.525-529
• /
• 2013

Contents of the total polyphenols and flavonoids in the dietary fiber from tubers and stalks of domestic sweet potatoes were investigated. In addition, their antioxidant activity as well as the potent anti-cancer effects through the growth inhibition in human colon cancer cells (HT-29) in vitro were tested. The total flavonoids as naringin equivalents in dietary fiber from tubers and stalks of sweet potatoes were $0.5{\pm}0.001$ naringin/g extract and $2.0{\pm}0.008$ mg naringin/g extract dry basis, respectively. The amounts of the total polyphenols as gallic acid equivalents were $2.8{\pm}0.01$ mg gallic acid/g dry basis and $6.3{\pm}0.03$ mg gallic acid/g dry basis, respectively. 1,2-Diphenyi-1-picrylhydrazyl (DPPH) radical-scavenging activity of the dietary fiber from stalks was 2.4 times higher than that of the dietary fiber from tubers. Interestingly, a strong growth inhibition on HT-29 cells was observed in both dietary fibers originated from stalks and tubers of sweet potato in a dose-dependent manner. In addition, we found that the dietary fiber from tubers and stalks of sweet potato increased the gene expression of tumor suppressor p53. The great potential value in the prevention of various diseases including cancer the potential value could be confirmed through effects of the dietary fiber from tubers and stalks of sweet potato on antioxidant activity and anticancer in human colon cancer.