Hye-Lim Jang

Biological Activities and Total Phenolic Content of Ethanol Extracts of White and Flesh-colored Solanum tuberosum L. Potatoes

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 μg/mL) were assessed for antioxidant activities of DPPH free radicals and hydroxyl radical scavenging. The cytotoxic activity of the extracts (0, 30, 60, 100 μg/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 HepG2 cells at the concentration 100 μg/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 HepG2 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.

Comparison of Physicochemical Properties and Antioxidant Activities between Lentinula edodes and New Cultivar Lentinula edodes GNA01

The new cultivar Lentinula edodes, which is named ‘Lentinula edodes GNA01’, was bred by mating strains isolated from ‘L26’ and ‘Kyoungwon9015’ obtained from Sammyungjin Research Institute, Fujian, China. L. edodes GNA01 does not have stipes like L. edodes, although it generally has a similar spherical shape. Moisture and crude protein contents of L. edodes GNA01 were lower than those of L. edodes. Meanwhile, L. edodes GNA01 contained higher levels of crude ash, crude lipid, crude fiber, and carbohydrates than L. edodes. The β-carotene content (19.05 μg/100 g) of L. edodes GNA01 was about three times higher than that of L. edodes. In addition, vitamin D content (118.53 μg/100 g) of L. edodes GNA01 was more than twice that of L. edodes. L. edodes GNA01 was a good source of mineral elements, with K and Mg contents of 2,277.50 mg/100 g and 203.15 mg/100 g, respectively. The major fatty acids of L. edodes GNA01 were C16:0 and C18:2, and L. edodes GNA01 had the highest linoleic acid (C18:2) content of 1,087.66 mg/100 g. Total phenol content of L. edodes GNA01 was 12.52 mg GAE/g, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities and ferric reducing antioxidant power (FRAP) values of L. edodes GNA01 were lower than those of L. edodes at all concentrations. However, DPPH radical scavenging activities and FRAP values of L. edodes GNA01 were above 80% and 0.9 at a concentration of 10 mg/mL, respectively.

Establishment of Mixing Ratio of Multigrain Rice for Adolescent and Aged People and Its Nutritional and Functional Estimation

This study was conducted to determine the proper mixing ratio of multigrains-added cooked rice for adolescent and aged people and analyze the nutritional and functional properties. As a result of sensory evaluation according to mixing ratio of polish rice and grains, the palatable grain mixing ratio of mixed grain rice for adolescent and aged people was 40% and 30%, respectively. The ratio of general grains to specialized grains was 9:1 in mixed grain rice for adolescent (MGA) and 8:2 in multigrain rice for aged people (MGAP). The ratio of mung bean to BacTae was 2:1 in MGA, and the ratio of adlay to buckwheat was 1:1 in MGAP. MGA contained the highest amount of crude protein, crude fat and minerals among the samples. In contrast, MGAP showed higher amounts of polyphenols and antioxidant activity compared to polished rice and MGA.

Nutritional compositions in roots, twigs, leaves, fruit pulp, and seeds from pawpaw (Asimina triloba [L.] Dunal) grown in Korea

Pawpaw (Asimina triloba L.) roots, twigs, leaves, fruit, and seeds were analyzed for their nutritional compositions. Seeds exhibited significantly higher levels of crude protein, lipid, fiber, and dietary fiber than those of the other parts. Sucrose in fruit was 9321.24 mg%, which was the highest among the samples. The total essential amino acid to total amino acid ratio was highest in the leaves, and the leaves contained the highest amount of potassium. The calcium content ranged between 8.15-153.41 mg%. Oleic and linoleic acids in seeds were 5905.11 and 8045.56 mg%, respectively, which were the highest among the pawpaw parts. The highest amount of linolenic acid was measured in the leaves, and β-carotene, vitamin C, and vitamin E were also the most abundant in the leaves. These results suggest that every part of pawpaw is a good source of an important food item. Additionally, this study provides basic data for improving the sitological value of pawpaw.

Changes in the phenolic compounds and antioxidant activities of mustard leaf (Brassica juncea) kimchi extracts during different fermentation periods

This study was conducted to investigate the changes in the total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activities of 80% methanol and water extracts from mustard leaf kimchi during different fermentation periods. The methanol extract exhibited higher TPC and TFC than the water extract. Both extracts from kimchi fermented for two months showed the highest antioxidant effects against the scavenging activities of 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radicals and 2,2-azino-bis diammonium salt (ABTS) radicals. Moreover, the methanol extract from kimchi fermented for two months showed the highest nitrite scavenging activity. The highest metal (Fe2+) chelating effect of the methanol extract and water extract was observed after three months and one month, respectively. Caffeic acid showed the highest increase with fermentation. These findings suggest that the antioxidant activities of kimchi depend on the fermentation period. Accordingly, this study provides basic data for improving the antioxidant activity of mustard leaf kimchi through the establishment of their fermentation period.