• Journal of the East Asian Society of Dietary Life
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• v.25 no.5
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• pp.893-901
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• 2015

This study investigated the effects of thawing conditions on physiological activities and quality of peeled garlic. Peeled frozen garlic was analyzed after thawing at low temperature ($4^{\circ}C$), room temperature ($20^{\circ}C$), tap water ($20^{\circ}C$), radio frequency of 27.12 MHz, and 2.45 GHz in a microwave. As a result, the time required to thaw garlic to $0^{\circ}C$ by various thawing methods was shortest at2.45 GHz in a microwave, followed by $20^{\circ}C$ tap water, radio frequency of 27.12 MHz, $20^{\circ}C$, and $4^{\circ}C$. Microwave thawing was faster than other methods, but it resulted in significant non-uniformity of heating. The hardness of peeled garlic significantly decreased upon freeze-thawing, whereas it showed improved hardness upon radio-frequency thawing. Total color difference in garlic increased upon freeze-thawing, and it was not improved by various thawing methods. Antioxidant activities were determined for DPPH radical scavenging ability, SOD-like activity, and reducing power. Total phenolic compounds and flavonoids in garlic extract were measured as $3.222{\pm}0.214{\mu}g$ GAE/g and $0.149{\pm}0.03{\mu}g$ QE/g, respectively. The content of total phenolic compounds was significantly reduced by 2.45 GHz microwave thawing ($1.90{\pm}0.02{\mu}g$ GAE/g); however, flavonoid contents were slightly reduced under freezing and thawing conditions. The DPPH radical scavenging ability of garlic extracts was not affected by thawing methods; however, SOD-like activity and reducing power were slightly reduced by freeze-thawing. These results indicate that physiological activities were not improved by radio-frequency thawing; however, thawing time and maintain hardness were reduced compared with conventional thawing methods.

• Preventive Nutrition and Food Science
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• v.19 no.1
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• pp.34-39
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• 2014

This study evaluated the influence of cooking methods (blanching, pan-frying, and microwaving) on the antioxidant activity of Ligularia fischeri (LF) using myoglobin methods against five different reactive oxygen species (ROS) (i.e., 2,2-diphenyl-1-picrylhydrazyl (DPPH), hypochlorite ions, hydroxyl radicals, peroxyl radicals, and peroxynitrite ions). With respect to DPPH scavenging activity, the antioxidant activities of blanched LF and pan-fried LF were significantly higher (P<0.05) than that of fresh LF for all cooking times. Pan-fried LF and microwaved LF showed higher antioxidant activities against hydroxyl radicals and peroxyl radicals than uncooked LF, while the protective effect of blanched LF was low, except for the at the 3 min cooking time point. Microwaved LF showed high antioxidant activity against all ROS at the 2 min cooking time point. Interestingly, LF that had been microwaved for 2 min and 3 min had high antioxidant values, whereas blanched LF and pan-fried LF had low antioxidant values. The activities of cooked LF against five different ROS were characterized comprehensively by 5-axe cobweb charts.

• Food Science and Preservation
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• v.22 no.3
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• pp.428-436
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• 2015

Five extraction conditions (AE, autoclave extraction; OE, oven extraction; HWSE, hot water and sonication extraction; HWASE, hot water acidified with 0.5% (v/v) acetic acid and sonication extraction; and BE, boiling extraction) were examined to compare the effects of different hot water extraction methods on the antioxidant properties of blueberries. The extraction yields of the AE, OE, HWSE, HWASE, and BE were 7.94%, 8.35%, 8.55% 9.15%, and 8.50%, respectively. The polyphenol and flavonoid contents of AE were 3.47 mg GAE/g and 1.59 mg RE/g, respectively, which were highest centents among others. Those of OE were ranked second to the highest. The total anthocyanin content of HWSE (5.29 mg/g) was significantly higher than that of others whereas that of AE showed the lowest content (0.96 mg/g). The order of ABTS radical and alkyl radical scavenging activities was as follows: AE > BE > OE > HWSE > HWASE. The antioxidant properties were considerably correspondent with the total polyphenol and flavonoid content. DPPH radical scavenging activity was quite high in HWSE, AE, and BE extraction, however, there were no significant differences among the five extraction methods in the aspect of $Fe^{2+}$ ion chelating activities. Moreover, AE showed the highest SOD activity, and protected the dermal fibroblast the best against $H_2O_2$-induced cytotoxicity. In conclusion, it was suggested that the autoclave extraction (AE) would be the most effective method for preparing blueberry hot water extracts with relatively high antioxidant activities.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.3
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• pp.350-358
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• 2014

This study investigated the changes of antioxidant compounds and antioxidant activity of adzuki bean by drainage methods in poorly drained sloping paddy field. The soil moisture contents of under pipe and open ditch drainage on very poorly drained paddy soil were $18.52{\pm}4.58$ and $19.01{\pm}4.25%$, and imperfectly drained paddy soil were $14.87{\pm}4.82$ and $18.64{\pm}3.85%$, respectively. Moisture, protein, fat and ash contents of adzuki bean with drainage methods were 10.10~11.60, 14.13~21.75, 0.02~0.73 and 2.81~3.45 g/100 g, respectively. The total polyphenol, flavonoid and tannin contents, and radical scavenging activity of adzuki bean showed significant differences by drainage methods. The total polyphenol, flavonoid, and tannin contents by drainage methods were 2.73~4.14 mg GAE/g, 1.07~1.43 mg CE/g, and 1.27~1.84 mg TAE/g, respectively. The DPPH and ABTS radical scavenging activities were 2.84~4.47 and 5.11~6.74 mg TE/g, respectively. The antioxidant compounds and radical scavenging activity of the adzuki bean by drainage methods were frequently affected soil water.

• The Korean Journal of Food And Nutrition
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• v.30 no.3
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• pp.482-490
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• 2017

This study was carried out to analyze the pasting and antioxidant characteristics of cooked mixed grains consisting of germinated millet and rice with varying addition rates and cooking methods. In this study, we chose two foxtail millets: glutinous ('Samdachal') and non-glutinous ('Samdame'), along with a glutinous proso millet ('Ibaekchal'). Cooked mixed grain rice-added germinated millet was cooked by general and high pressure cooking methods, with and without fermented alcohol. The peak and trough viscosity of germinated millet were decreased significantly with increasing amounts of germinated millet. The phenolic compounds and radical scavenging activity of cooked rice-added germinated millet increased significantly with the addition of germinated millet (p<0.05). The total polyphenol contents of cooked rice-added germinated Samdachal, Samdame, and Ibaekchal were 127.74~194.11, 128.20~192.56, and $128.88{\sim}171.28{\mu}g\;GAE/g$, respectively. The total flavonoid contents were 13.79~30.23, 14.77~25.99, and $15.28{\sim}29.56{\mu}g\;CE/g$, respectively. DPPH and ABTS radical scavenging activities were 3.31~5.73 and 6.31~9.69 mg TE/100 g for cooked rice-added germinated Samdachal; 3.14~8.58 and 6.05~10.19 mg TE/100 g for Samdame; and 3.37~7.45 and 6.27~9.27 mg TE/100 g for Ibaekchal, respectively. In this study, phenolic compounds and radical scavenging activity of cooked mixed grain rice-added germinated millet with different addition rates and cooking methods can be used as basic data for manufacturing processed products.

• Food Science and Preservation
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• v.23 no.2
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• pp.233-238
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• 2016

A effect of extraction methods, including stirrer extraction method (SE), ultrasonification extraction method (USE), reflux extraction method (RE), autoclave extraction (AE) and low temperature high pressure extraction (LE) method on the antioxidative and antimicrobial activities of ethanol extracts of Oenothera biennis was investigated. The extraction yield (46.33%), total polyphenol (463.05 mg GAE/g) and flavonoid (71.71 mg RHE/g) content of Oenothera biennis extract obtained by RE were higher than those from other extraction methods. The antimicrobial activity of Oenothera biennis extract was only observed against Bacillus cereus among other tested organisms (Bacillus cereus, Staphylococcus aureus, Escherichia coli and Salmonella Typhimurium). Oenothera biennis obtained by RE showed the best DPPH radical scavenging ability (74.40%), ABTS radical scavenging ability (65.29%), reducing power (1.370 ($OD_{700}$)) and ferrous ion chelating ability (90.14%) compared with other tested extraction methods tested. The RE method was the most efficient method for extracting crude antioxidant and antimicrobial substances from Oenothera biennis. These results suggested that Oenothera biennis obtained by RE could be used as a bioactive and functional material in the food industry.

• Korean Journal of Food Science and Technology
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• v.49 no.3
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• pp.311-317
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• 2017

In this study, the phenolic content and antioxidant activity of rice cooked using different methods with different amounts of germinated brown rice (10, 20, 30, and 50%) were compared. Germinated brown rice was cooked using general and high-pressure cooking methods with and without fermented alcohol. Pasting characteristics decreased, and total polyphenol and flavonoid contents, and DPPH and ABTS radical scavenging activities increased with increasing amounts of germinated brown rice. Moreover, germinated brown rice cooked by general cooking method with fermented alcohol showed higher antioxidant activity than that showed by rice cooked by other cooking methods. The results obtained in this study are expected to serve as basic data for manufacturing of processed products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1249-1254
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• 2013

The effect of extraction methods, such as reflux extraction (RE), autoclave extraction (AE), low temperature high pressure extraction (LTPE) and ultrasonification extraction (USE) on antioxidant activity of various species of Artemisia (Artemisia capillaris T., Artemisia princeps P., Artemisia annua L.) was investigated. The extraction yield of RE and AE was higher than other methods tested for all Artemisia. The total polyphenol and flavonoid content of Artemisia sp. extracts from RE was highest of the extraction methods tested. The total polyphenol and flavonoid content of A. capillaris T. extracted by RE was 260.82 mg GAE/g and 11.52 mg RHE/g, respectively. The A. capillaris T. extract showed higher DPPH and ABTS radical scavenging activity than that of the other tested Artemisia sp. Nitrite scavenging activity and superoxide dismutase (SOD)-like activity of various extracts from RE was 45.48% and 68.29% (A. capillaris T.), 45.73% and 61.43% (A. princeps P.), and 44.25% and 58.19% (A. annua L.), respectively. The RE method was the most effective method for extracting antioxidant substances from various A. capillaris T. compared with AE, LTPE and USE. These results suggest that extracts of Artemisia sp. from RE can be used as bioactive and functional materials in the food industry.

• The Korean Journal of Food And Nutrition
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• v.26 no.1
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• pp.29-34
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• 2013

The objective of this study was to manufacture three kinds of domestic sweet potato Makgeolli using a mixture design and an optimization technique. The effects of four different manufacture methods, such as simultaneous saccharification and fermentation (SSF) with or without malt and separate hydrolysis and fermentation (SHF) with or without malt were determined. The SSF methods of Makgeolli produced higher alcohol content than that of SHF methods. The sensory score was not influenced by different making methods. Fourteen experimental points were selected, and rice (10~50%), sweet potato (10~50%) and water (40~60%) were chosen as independent variables. The measured responses were sensory preference, total polyphenol content, and DPPH radical scavenging activities. The ratio of the optimum sweet potato Makgeolli mixture formulation was developed as 15.11 (rice): 44.89 (sweet potato): 40 (water) using the optimization technique. The desirability of the optimum mixture formulation was 0.839. Yellow sweet potato Makgeolli using the optimum mixture formulation produced higher soluble sugar content compared to others. Regular sweet potato Makgeolli produced higher pH. The purple sweet potato Makgeolli's total polyphenol content and DPPH radical scavenging activity were measured to be the highest at $771.91{\pm}1.42mg\;GAE/{\ell}$, $131.55{\pm}4.03%$.

• Food Science and Preservation
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• v.23 no.1
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• pp.97-103
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• 2016

The antioxidant and digestive enzyme inhibitory effects of Eisenia bicyclis extracted by various extraction methods (RE, reflux extraction; SE, ultrasonification extraction; AE, autoclave extraction; LE, low-temperature high-pressure extraction) were investigated. The extraction yield (55.21%) and the laminarin (39.03%), fucoidan (24.75%), total polyphenol (115.68 mg GAE/g) and flavonoid (36.67 mg RHE/g) contents of AE were higher than those in other methods. The DPPH radical (86.60%, 500 mg%), ABTS radical (58.56%, 25 mg%), nitrite (86.38%, 100 mg%) scavenging activities of the Eisenia bicyclis extracted by AE were higher than those of Eisenia bicyclis extracted by other methods. The ABTS radical and nitrite scavenging activities were above 98% in all tested Eisenia bicyclis extracts and these activities were dependent on its concentration. The inhibitory effects of AE against amylase (50 mg%) and ${\alpha}$-glucosidase (5 mg%) were 64.76% and 86.71%, respectively. The AE showed the best inhibitory effect of Eisenia bicyclis extracts (50 mg%) against trypsin (24.37%) and ${\alpha}$-chymotrypsin (49.05%), respectively. These results suggest that Eisenia bicyclis extracted by AE can be used as a bioactive and functional material in the food industry.