• Journal of Applied Biological Chemistry
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• v.61 no.1
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• pp.25-31
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• 2018

This study investigated the effect of different $O_2$ transmission rate (OTR) of films on surface temperature, weight loss, pH, $O_2$, $CO_2$ and sensory characteristics, microbial quality, total phenolic contents and 1,1-diphenyl-2-picryl hydrazyl radical scavenging activity of fresh-cut lettuce during storage at $10^{\circ}C$ for 7 days. $80{\pm}5g$ of fresh-cut lettuce were packaged with oriented polypropylene films respectively. The OTR of packaging materials was 5,000, 8,000 and $10,000cc/m^2{\cdot}day{\cdot}atm$. Quality characteristics showed significant differences during storage. The surface temperature was averaged 13 and lower in higher OTR of films. The weight loss of lettuce ranged from 2.8 to 5.4% and the highest loss showed in $5,000cc/m^2{\cdot}day{\cdot}atm$ of film. pH was increased during storage and the highest pH was found in $5,000cc/m^2{\cdot}day{\cdot}atm$. The $O_2$ content in the packaging was decreased with increasing $CO_2$ content during storage. The lowest $CO_2$ was found in $10,000cc/m^2{\cdot}day{\cdot}atm$. As OTR was decreased, antioxidant profile of lettuce was decreased. Total aerobic bacteria showed from 5.48 to 6.59 log CFU/g. From the result of the overall sensory test, the marketability of fresh-cut lettuce stored at $10^{\circ}C$ seemed to be maintained effectively over 5 days.

• Journal of Applied Biological Chemistry
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• v.52 no.4
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• pp.200-204
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• 2009

The change of biological activities of melon were investigated during frozen storage. The total phenolic concentrations in melon juice and water extract were 296.25 and $433.25\;{\mu}g/mL$, respectively. The total flavonoid contents in melon juice and water extract were 20.83 and $53.58\;{\mu}g/mL$, respectively. Antioxidant activities of melon juice and water extract were determined. The DPPH of water extract of melon (85.84%) was higher than the melon juice (60.58%). ABTS of melon juice and water extract were 94.50 and 99.30%, respectively. SOD-like activity and xanthine oxidase inhibitory activity of melon of water extracts were higher than those of melon juice. $\alpha$-Glucosidase inhibitory activity of melon juice and water extract were 22.42 and 23.43%, respectively. The changes in the antioxidant activity of melon was insignificant until 6 months of frozen storage. Therefore, it was expected that frozen storage of melon was useful preservation expedient for consistent supply of raw materials.

• Food Science and Preservation
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• v.23 no.3
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• pp.387-392
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• 2016

The antioxidant activities of brownish natural dyeing agents, extracted from seven kinds of plants, were tested. Total polyphenol content, DPPH and ABTS radical scavenging activities, and singlet oxygen quenching effect were determined for hot water extracts and floral waters of plants. DPPH and ABTS radical scavenging activites increased with increasing amounts of the extracts from Uncaria gambir R. and Terminalia chebula R. displayed remarkable scavenging effects at concentrations below 0.1 mg/mL, in comparison with the positive control, ascorbic acid. However, antioxidant effects of the floral water, obtained from steam distillation of tested plants, were inefficient at concentration below 0.2 mg/mL. In particular, the natural dyeing agent effectively suppressed singlet oxygen induced by photosensitizer in in vitro assay systems. The concentrations ($IC_{50}$) required to exert 50% of singlet oxygen were 120 and $190{\mu}g/mL$ for hot water extracts from Uncaria gambir R. and Phellinus linteus, respectively. Among all the tested samples, the Uncaria gambir R. and Phellinus linteus extracts contained higher amount of total phenolic contents. The results suggest that naturally occurring dyeing agents are beneficial as natural antioxidants, encouraging further extensive studies.

• Food Science and Preservation
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• v.17 no.1
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• pp.131-138
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• 2010

To obtain basic data on the use of lotus as a raw material in functional food, antioxidant and anticancer activities of the leaf and root were investigated. Total flavonoid and total phenolic contents, at 12.84 mg/g and 24.33 mg/g respectively, were higher in white lotus leaf (WLL) than in any other part of the plant. The radical-scavenging activity of different tissues of lotus, measured in the DPPH radical-scavenging assay, increased with higher concentrations of solvent fractions. The butanol fraction of white lotus leaf showed the highest DPPH radical-scavenging activity. The reducing power of fractions increased in a dose-dependent manner. The butanol fraction of WLL had the greatest reducing power, and showed strong antioxidant activity in the linoleic acid system, and high-level inhibition of tyrosinase. Fractions from lotus were also capable of scavenging nitrite, depending on the concentration of the fractions. Butanol fractions of the leaf of white and red lotus scavenged 95.61% and 92.15% of available nitrite, respectively, when used at 1 mg/mL concentrations. Butanol fractions from leaf of white and red lotus exhibited the strongest inhibitory effects on human lung and colon cancer cells.

• Food Science and Preservation
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• v.17 no.1
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• pp.139-144
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• 2010

This study was carried out to investigate potential applications of the extract of Castanopsis cuspidata var. sieboldii $N_{AKAI}$ nut as a functional food ingredient. The pH and $^{\circ}Brix$ of nut were 6.43 and 3.17, respectively. L, a and b values as Hunter's color were 83.07, 1.49 and 10.48, respectively. Total content of monosaccharide was 54.26 mg% and organic acids were composed of oxalic acid 495.37 mg%, formic acid 200.03 mg%, malic acid 93.65 mg%, citric acid 27.80 mg%, and succinic acid 16.61 mg%. Total phenolic contents in various solvent extracts were as follows: water 27.69 mg%, 75% ethanol 16.50 mg%, ethyl acetate 16.50 mg%, and methanol 10.30 mg%. The antioxidant activity ($SC_{50},\;{\mu}g/mL$) of the nut extracts by various solvents was in the order of ethyl acetate 74.88 > methanol 155.00 > n-hexane 213.33 > ethanol 249.33 > butanol 274.78 > chloroform 314.67 > 75% ethanol 848.33 > water extracts 869.67. The results indicated that the extract of C. cuspidata nut contained a potential food ingredient.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1415-1422
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• 2014

Hot water extraction concentrate was prepared from Alliun hookeri root (AHR) to evaluate its applicability to yogurt. The highest antioxidant activity of hot water concentrates was obtained under extraction conditions of 4 hr at $95^{\circ}C$. Antioxidant activities measured by DPPH radical assay, ABTS radical cation assay, reducing power, and cheating activity were highly correlated with total phenolic (89.51 mg/g) and total flavonoid (52.71 mg/g) contents, with R values of 0.94 and 0.96, respectively. Yogurt was fermented with a commercial lactic acid bacteria mixed strain (Yo-mix$^{TM}$ 305) for 10 hr at $42^{\circ}C$ after addition of 0~10% (w/w) hot water concentrates from AHR to yogurt base. As fermentation proceeded, pH and $^{\circ}Brix$ of yogurt decreased from 6.57~6.60 to 4.34~4.51 and from 8.10~8.90% to 4.60~5.25%, respectively, whereas titrate acidity, viscosity, and viable cell numbers increased from 0.22~0.23% to 1.01~1.10%, from $0mPa{\cdot}s$ to $202.55{\sim}290.50mPa{\cdot}s$, and from 6.40~6.80 log CFU/mL to 8.60~9.20 log CFU/mL, respectively. There was no significant difference in any sensory attribute between the control and 2.5% addition group, suggesting that 2.5% hot water concentrate from AHR could be used to manufacture yogurt.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.12
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• pp.1628-1632
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• 2007

The present study describes the preliminary evaluation of antioxidant activities and antigenotoxic effect of Rhododendron mucromulatum Turcz. flowers (RMF). The samples were prepared by extracting RMF with four different solvents (methanol, ethanol, acetone, and water), and antioxidant properties were evaluated by determining total phenolic contents (TPC), DPPH radical scavenging activity (RSA), and reducing power (RP). Water extract showed the highest total phenol content (328.1 mg/g gallic acid equivalents). Acetone extract showed the most potent RSA and RP. The $IC_{50}$ for RSA and RP in the acetone extract were 78 mg/mL and 454 mg/mL, respectively. The 200 mM $H_2O_2$ induced DNA damage, measured by Comet assay, was inhibited with water, methanol and acetone extract in dose dependent manner in human leukocytes. The inhibition rates were 42, 62, and 52% at the concentrations of 50 mg/mL of water, methanol and acetone extracts, respectively. These results suggest that R. mucromulatum Turcz. has significant antioxidative activity and protective effect against oxidative DNA damage.

• The Korean Journal of Food And Nutrition
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• v.19 no.4
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• pp.398-409
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• 2006

Changes of component(amino acid, free sugar, fatty acid and mineral) and antioxidant effect by pickling of soybeans we.e investigated. Soybean cultivars, Daewon, Pungsannamul, Hwaeum(yellow bean), Ilpum Black and Zynuni(black bean) were soaked in persimmon vinegar for 10 days at $20^{\circ}C$. The major amino acids of raw soybeans were glutamic acid, aspartic acid, lysine and leucine. The content of total amino acid decreased by pickling. The major free sugar of raw soybeans were glucose, fructose and sucrose. Sucrose decreased and glucose and fructose increased by pickling. Maltose was found only in pickled Daewon and Ilpum Black. Linoleic and linolenic acid content of raw soybeans were $49.3%{\sim}57.1%\;and\;7.8{\sim}8.9%$, and the fatty acid contents did not change by pickling. The major mineral elements were K, P and Mg, and their compositions except for Na did not change by pickling. Total phenolic compound, vitamin $B_1$ and C content increased during pickling. The antioxidant effects, electron donating abilities, nitrite-scavenging abilities increased by pickling.

• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.206-212
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• 2013

In the current study, antioxidant properties of extracts from different parts of Taraxacum officinale were determined by measuring the radical scavenging activity of 1,1-diphenyl-2-picryl hydrazyl(DPPH) and 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). The antioxidant activity of aerial and root parts of this plant was measured in extracts obtained from various solvents, e.g., water, 50, 70, 100% ethanol, and hot-water. The hot-water extracts had the highest radical scavenging activities. A further study was conducted to determine the total antioxidant activity of hot-water extract fractions obtained from different solvents, e.g., chloroform, ethyl acetate, n-butanol, and water. The ethyl acetate fraction of this extract displayed the strongest DPPH and ABTS radical scavenging activity and the highest total phenolic contents. The inhibitory effect of individual solvent fractions on the production of nitric oxide in LPS-stimulated RAW 264.7 cells was measured. The results indicated that the ethyl acetate fraction of aerial and roots part extracts significantly reduced nitric oxide productions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1211-1219
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• 2013

Dasik is a kind of traditional Korean dessert, which has polysaccharides as the major base. Dasik was prepared using rice and various ingredients and its antioxidant properties were determined. In addition, textural changes and sensory evaluation were conducted on Dasik during 7-day storage at $4^{\circ}C$. Dasik containing brown rice, red ginseng, and rice bran oil showed higher radical scavenging ability, reducing power, total flavonoid, and total phenolic contents among tested rice-based samples. Dasik prepared using black sesame seeds showed the highest radical scavenging ability and reducing power compared to rice-based Dasik. In sensory evaluation, 10 trained panelists found that hardness of the rice-based Omija Dasik sample increased significantly (P<0.05) while moistness and softness attributes decreased as the storage period of Dasik increased. The roasted bean Dasik and black sesame Dasik samples were evaluated similarly and their moistness decreased significantly (P<0.05) with longer storage period. The overall and texture acceptability of the rice-based Omija Dasik and the roasted bean Dasik samples decreased significantly (P<0.05), and scores of willingness to try again of the rice-based Omija Dasik decreased as the storage period of Dasik increased. Positive or negative correlations among the results from sensory evaluation and textural analysis were observed in Dasik.