• Current Research on Agriculture and Life Sciences
• /
• v.28
• /
• pp.25-29
• /
• 2010

The colored sweet potato, particularly purple sweet potato, has been well known to contain anthocyanins abundantly. This study was conducted to examine the antioxidant properties of purple sweet potato. The chopped purple sweet potato was extracted 2 times with water or acetone for 18 hours at $28^{\circ}C$. The antioxidative potential of each solvent extract was assessed by DPPH free radical scavenging activity assay, FRAP assay, and total phenolic contents. The results showed that both extracts had not only high DPPH free radical scavenging activity but had high level of total phenolic compounds. Furthermore, both solvent extracts were found to have antioxidative effects in human colon cancer cells (HCT 116, HT 29) in DCFDA assay. The notable antioxidant activity of purple sweet potato suggests its significant health benefit and deserves further study to develop into functional food ingredient.

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

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.52 no.4
• /
• pp.447-452
• /
• 2007

This experiment was conducted to enhance the colored potatoes utilization and to determine the biological activity of colored potato extracts. In order to understand the factors responsible for the potent antioxidant and antihypertensive ability of colored potatoes, it has been evaluated for anti-oxidative activity using Fenton's reagent/ethyl linoleate system and for free radical scavenging activity using the 1,1-diphenyl-2-picryl hydrazyl free radical generating system. There were significant differences of antioxidant activities in $50{\mu}g/mL$ extracts treatment among different colored potatoes. About two-fold higher radical scavenging activity was found in 'Daegwan 1-102', 'Daegwan 1-104' and 'Jasim' compared to that in 'Superior'. Based on the flesh color tested, potatoes with purple tuber showed higher radical scavenging activity than red potatoes, while white potato showed the lowest radical scavenging activity. The ability of 80% ethanol extracts from colored potatoes to influence the inhibitory activity of angiotensin converting enzyme(ACE) and xanthine oxidase(XOase) has also been investigated. Expect 'Jasim', the high levels of inhibition activity of xanthine oxidase in two colored potatoes such as 'Daegwan 1-102' and 'Daegwan 1-104' were highly correlated to $IC_{50}$ values of ACE inhibition activity. The various therapeutic benefit claims in the new functional medicinal usage of colored potatoes ascribed to the phenolic compounds and anthocyanin. This result revealed that the extracts of colored potatoes are expected to be good candidate for development into source of free radical scavengers and anti-hypertentive agent.

• Culinary science and hospitality research
• /
• v.20 no.4
• /
• pp.157-168
• /
• 2014

We investigated the anti-obesity effects of small colored potato extracts by high pressure water extraction process on body weight, plasma lipid levels in high-fat diet-induced obese mice. Experimental groups were divided into basal diet only (Normal), high fat diet control (HFD), small colored potato water extracts (CP), and high-fat diet and small colored potato water high pressure extracts (HCP) groups. The levels of hematological variables were not significantly different among the four groups. Compared with the HFD group's serum total cholesterol level of $86.01{\pm}1.16mg/dL$, the levels of the CP and HCP groups were significantly lowered to $80.29{\pm}1.28$ and $77.21{\pm}4.21mg/dL$, respectively. Compared with the HFD group's LDL-cholesterol level of $18.92{\pm}2.44mg/dL$, the LDL-cholesterol levels of the CP and HCP groups were significantly lowered to $13.52{\pm}1.26$ and $12.93{\pm}1.26mg/dL$, respectively. Also, compared to the HFD group's serum triglyceride level of $82.71{\pm}3.94mg/dL$, the level of the HCP group was significantly lowered to $63.24{\pm}6.32mg/dL$. These results suggested that dietary supplementation of small colored potato extracts using high pressure water extraction does not have any adverse effects on the hematological variables, while improving the lipid content and reducing hepatic damage of the high-fat fed rats.

• Biomedical Science Letters
• /
• v.17 no.1
• /
• pp.55-60
• /
• 2011

Skin is a physical barrier against diverse injury and damages. Exposure to ultraviolet (UV) radiation causes detrimental skin injuries such as inflammation and cell death. The value of natural pigments could be applied to many usages including cosmetics. This study was conducted to examine the protective effect of natural pigments extracted from mulberry, balsam pear, purple-colored sweet potato, pehmannia root, gardenia fruit, and black rice against UV-induced cell death in HaCaT cells, human keratinocyte cell lines. In the present study, the exposure of 50 mJ/$cm^2$ UV-B for 24 hr induced cell death in HaCaT cells, which was prevented by the pretreatment of extracts of mulberry, balsam pear, purple-colored sweet potato, rehmannia root, gardenia fruit, and black rice. In addition, the exposure of 50 mJ/$cm^2$ UV-B for 24 hr also increased lipid peroxide (LPO) formation, compared to control in HaCaT cells, which was prevented by the pretreatment of extracts of mulberry, balsam pear, purple-colored sweet potato, rehmannia root, gardenia fruit, and black rice. In conclusion, the extracts of mulberry, balsam pear, purple-colored sweet potato, rehmannia root, gardenia fruit, and black rice prevented the UV-B-induced cell apoptosis via the inhibition of oxidative stress in HaCaT cells.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.41 no.8
• /
• pp.1035-1040
• /
• 2012

This study was aimed to evaluate and compare the biological activities and total phenolic content of ethanol extracts of white (Superior) and colored potatoes (Red, Rose, Haryoung, Blue, Jaseo, and Jasim). Various ethanol extracts (250, 500, 1,000, and $2,000{\mu}g/mL$) were assessed for antioxidant activities of DPPH free radicals and hydroxyl radical scavenging. The cytotoxic activity of the extracts (0, 30, 60, $100{\mu}g/mL$) was also carried out by a human cancer cell lethality bioassay method. Results showed that the DPPH and hydroxyl radical scavenging activities, of all extracts increase in a concentration-dependant manner. All color-fleshed potato extracts, except for Red and Haryoung, showed higher radical scavenging activities than the general white potato extract. Cytotoxicity of the extracts as determined in THP-1 cells showed that Blue and Jasim was highly toxic at most concentrations tested. In addition, the Blue extract had the highest cytotoxic activity on $HepG_2$ cells at the concentration $100{\mu}g/mL$. The contents of total phenolic (TPC) in the extracts significantly varied from 120.0 mg/100 g powder (Superior) to 151.1 mg/100 g powder (Blue), and TPC of all color-fleshed potato extracts was higher than that of white. The greatest positive correlation was found between phenolic contents and hydroxyl radical scavenging activity (r=0.776, p<0.05), and a strong negative correlation was found between hydroxyl radical scavenging activity and cytotoxic activities on $HepG_2$ cells (r=-0.795, p<0.05). The present study demonstrates that color-fleshed potatoes have higher antioxidant and stronger anticancer activities than general potato. These results provide useful and important information for potato breeders and researchers, in order to increase the antioxidant capacity and functional value of colored potatoes for use in the food and pharmaceutical industries.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.53 no.2
• /
• pp.233-238
• /
• 2008

This experiment was conducted to enhance the colored potatoes utilization and to determine the biological activity of colored potato extracts. In order to understand the factors responsible for the potent anti-oxidant ability of colored potatoes, it has been evaluated for anti-oxidative activity using oxygen radical absorbance capacity (ORAC) assay. 'Hongyoung' extract was significant anti-oxidant activities in ORAC assay. About two-fold higher radical absorbance capacity was found in 'Hongyoung' compared to that in 'Jayoung'. The ability of 80% ethanol extracts from colored potatoes to influence the inhibitory activity of nitric oxide (NO) and nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) has also been investigated. The various therapeutic benefit claims in the new functional medicinal usage of colored potatoes ascribed to the phenolic compounds and anthocyanin. This result revealed that the extracts of colored potatoes are expected to be good candidate for development into sources of free radical scavenger or COX-2 inhibiting agents.

• The Korean Journal of Food And Nutrition
• /
• v.25 no.3
• /
• pp.529-537
• /
• 2012

This study examined the manufacturing characteristics of sweet potato doenjang in order to gain a more efficient use of the sweet potato. Sweet potato(Sinwhangmi, Sinjami) koji(mixed sweet potato paste and soybean powder in a ratio of 1:1) was cultured with Aspergillus oryzae KCCM 11372 at $35^{\circ}C$ for 48 h. Sweet potato doenjang was fermented for 60 days using a sweet potato koji(20%, 45%) and steamed soybean(70%, 45%), with salt accounting for 10%. The glutamic acid content was determined to be much higher in sweet potato doenjang using Sinwhangmi koji(45%) and steamed soybean (45%), than that of general doenjang. The DPPH radical scavenging activity has the largest $EC_{50}$(0.9 mg) in sweet potato doenjang using Sinjami potatoes 45%. Sensory evaluation indicated a good preference for sweet potato doenjang using Sinwhangmi(45%) and steamed soybean(45%).

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2001.11b
• /
• pp.25-32
• /
• 2001

Potatoes have been recognized for a long time as one of the major food crops as well as horticultural crops. Potato production as a table food has been decreased in developed countries, while it has been steadily increased in the third world countries for it importance as food source. It is a new trend to look for the food, not only as a feeding crop but also healthy food. It is also time for the potato producers to look for the potato having high economic value as found in medicinal plants. There are great diversities in potato species, indicating that valuable compounds can be found in different amounts, depending on potato species. We screened the cultivars, breeding clones, and germplasms based on the vitamin C, Vitamin E, antioxidant compounds, diverse sugar types, important amino acids, and other valuable compounds. We could select the breeding clones KC003, 98Wl17, 99j717, and Vally 8 (A group) due to their high levels of antioxidant compounds, and it can be said that most of the red and purple colored potato clones belong to the A group. In the contents of essential amino acids, ‘Taebook Valley’,‘Summer Valley’ and other breeding clones were found to be high in amount. We also made crosses between breeding clones with high biological function and low agronomic traits and low biological function with high quality in agronomic characteristics . The patterns of genetic trends of these offsprings in comparison with their parents will be reported as well. And the potential of using potato as antibody production of anti-cancer will be discussed.

• Journal of the Korean Society of Food Culture
• /
• v.20 no.4
• /
• pp.487-497
• /
• 2005

War against Japanese(1592-1599) and war against Manchurian(1636-1637), which had been occurred in Korean Peninsula throughout the history, and frequent trade with foreign countries since $18^{th}$ century have led to a distribution of foreign food into Korea. Several examples for this include tomato, apple, watermelon, maize, pea, cowpea, peanut, potato from China and red pepper, pumpkin, and sweet potato from Japan. Since these foods had been brought into Korea, they have been cultivated suitable for Korea's climate and land. Foreign foods with a few exceptions tend to have high calories. For instance, along with potato and sweet potato, pumpkin is considered a high-calorie food containing lots of starches as it becomes ripening. This helped a wide spread of the foreign foods across the nation where intake of high-calorie foods was critical for Korean people's nutrition at that time. Among those foods introduced from foreign countries, red pepper had a greatest impact on the dietary life-style of Chosun Dynasty. The use of red pepper has been greatly expanded from main ingredient to seasoning and garnishing in various forms of red pepper such as red pepper paste, red pepper powder, and thick soy paste mixed with red pepper. Red pepper was made eating habits is hot besides dye red colored to traditional food, because steaming and boiling is frequently cook method, fermentation food also food color is achromatic therefore food color is and mixture with red pepper, picked fish and chinese cabbage new kimchi culture came into being.