• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.6
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• pp.798-803
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• 2011

We investigated the changes in chemical composition and antioxidant activity of Deoduk (Codonopsis lanceolata) and Doragi (Platycodon grandiflorum) with heating. Deoduk and Doragi were heated to $110\sim150^{\circ}C$ for 2 hours. The total polyphenol content of Deoduk and Doragi reached high values of 6.31 and 7.34 mg/g, respectively, at $150^{\circ}C$. The total polyphenol content of raw Deoduk and Doragi were 0.60 and 0.59 mg/g, respectively. The DPPH radical scavenging activity ($IC_{50}$) of Deoduk and Doragi decreased from 13.94 and 6.83 mg/mL, respectively, in raw samples to 0.81 and 0.94 mg/mL, respectively, in samples heated to $150^{\circ}C$. The ABTS radical scavenging activity of Deoduk and Doragi increased from 0.43 and 0.21 mg AA eq/g, respectively, in raw samples to 3.55 and 4.83 mg AA eq/g, respectively, in samples heated to $150^{\circ}C$. The reducing power of raw Deoduk and Doragi was 0.1 and 0.06, respectively, which was increased to 0.54 and 0.50, respectively, in samples heated to $150^{\circ}C$. Fructose content decreased after heating to $130^{\circ}C$. The sucrose content of the samples increased slowly with heating up to $120^{\circ}C$, but was not detected at warmer temperatures. The organic acid and 5-HMF of the samples increased gradually with increasing temperature.

• Food Science and Preservation
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• v.16 no.3
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• pp.333-341
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• 2009

The antioxidant properties of green tea leaves and powder extracts were determined using several tests including estimation of reducing power, DPPH(1,1-diphenyl-2- picrylhydrazyl) radical-scavenging activity, and FRAP(Ferric reducing/antioxidant power) assay. All tests indicated that extracts of green tea powder had higher antioxidant activities than extracts of green tea leaves, and the activities were concentration-dependent. However, each test yielded somewhat different results with respect to storage conditions. The reducing power of green tea leaves was highest at $1,000{\mu}g/mL$, storage at $4^{\circ}C$, and an Aw(water activity) value of 0.23. However, the reducing power of green tea powder, assayed at $1,000{\mu}g/mL$, was high under all storage conditions(with variations in temperature and Aw), and was about 1.5.2-fold greater than that of green tea leaves. Radical-scavenging activity, as assessed by the DPPH assay, increased in a dose-dependent manner over the range $15{\sim}125{\mu}g/mL$. At higher concentrations, activities were $80{\sim}90%$ of maximal were attained. The FRAP activity of green tea extract also increased with rising concentration. Particularly in the case of green tea leaves, antioxidant activity was most greatest with storage at $-20^{\circ}C$ and Aw values of 0.69 and 0.23 when assayed at a concentration of $1,000{\mu}g/mL$. These results indicate that the most important factor during storage of green tea is not the Aw value but rather temperature, and that use of refrigeration($4^{\circ}C$) is preferable to increase or maintain the antioxidant activities of biological components in green tea.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.8
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• pp.1206-1212
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• 2010

This study was performed to establish optimum extraction condition of Tricholoma matsutake. A central composite design was applied to investigate the effects of independent variables, extraction temperature ($X_1$), extraction time ($X_2$) and water per sample ($X_3$) on dependent variables such as soluble solids contents ($Y_1$), total phenolics contents ($Y_2$), reducing sugar contents ($Y_3$), electron donating ability ($Y_4$) and nitrite scavenging ability ($Y_5$). The optimum extraction conditions were predicted and monitored by response surface methodology using SAS program based regression analysis. Soluble solids content, electron donating ability and nitrite scavenging ability were highly affected by water per sample. However, the contents of total phenolics and reducing sugar were affected by water per sample and extraction temperature as well. The optimum extraction conditions for soluble solids were 34.84 mL/g (water/sample) at $78.85^{\circ}C$, for 3.33 hr. In contrast, the optimum extraction conditions of electron donating ability were temperature of $91.00^{\circ}C$, time of 1.62 hr and water per sample of 39.42 mL/g. Taken together, the optimum ranges for hot water extraction of Tricholoma matsutake were $70{\sim}90^{\circ}C$, 2~4 hr and 30~50 mL/g.

• Food Science of Animal Resources
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• v.22 no.1
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• pp.20-29
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• 2002

The functional sausage added to effective extracts are prepared to carried out to investigate functional and storage characteristics. This products were stored at different temperature. The changes of pH were tended to be a little ranged from pH 6.07 to pH 6.35 in control. At the same time, the pH changes treated with plant extracts showed the same tendency as control. The treatments using natural extracts revealed a little low TBARS value during storage at 10$^{\circ}C$. The nitrite scavenging ability of extracts from pine needle were higher than those of green tea extracts, irrespective of storage temperature. The VBN content was tended to be increased as storage time goes by, irrespective of storage temperature. The treatments using plant extracts revealed a little low VBN content, compared to control during storage. The changes of total bacteria were more increased to 2.2${\times}$10$^1$∼3.2 ${\times}$ 10$\^$6/ CFU/g during storage at 30$^{\circ}C$ than 2.2${\times}$10$^1$∼3.3${\times}$10$^2$CFU/g in case of storage at 10$^{\circ}C$. The treatments using plant extracts revealed an antimicrobial activity until storage at 3 days, compared to control. The lightness of sausage color were a little more decreased gradually during storage at 30$^{\circ}C$ than those of storage at 10$^{\circ}C$. Overall, the lightness of sausage color treated with pine needle extracts were a more bright than those of control. However, the redness of sausage color treated with pine needle and green tea showed the most lowest red color, compared to control. Sensory test suggested that the changes of sausage color, flavor, texture and taste were tended to be decreased gradually. In conclusion, pine needle extract was the most effective natural resources on the basis of the functional and physico-chemical properties of sausage of sausage.

• The Korean Journal of Food And Nutrition
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• v.29 no.3
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• pp.438-447
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• 2016

This study was conducted in order to investigate the physiochemical properties and antioxidative activity of red ginseng manufactured using the high temperature high pressure (HTHP) process, which is faster and simpler than the conventional process. According to increasing the steaming temperature, pressure and time, the content of minor non-polar ginsenosides, such as Rg3, Rk3, Rh4, Rk1 and Rg5 gradually increased. Also, the contents of acidic polysaccharide, total phenolic compounds and maltol gradually increased. Based on the results of the physiochemical properties and appearance quality, the optimum conditions of HTHP process were estimated as $140^{\circ}C$, $3kg/cm^2$ in 20 min. The total phenolic compounds and maltol contents of the HTHP process red ginseng (1.0% and 2.49 mg%, respectively) were higher than those of conventional red ginseng (0.23% and 0.60 mg%, respectively). In addition, the antioxidative activity was investigated using DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-aziono-bis(3-ethylbenzthiazoline-6-sulfonic acid)) radical scavenging activity. DPPH and ABTS radical scavenging activities of HTHP process red ginseng increased by 3.4 and 3.6 folds, respectively, compared with conventional red ginseng. In addition, total phenolic compounds and maltol contents, as well as the antioxidant activity of the HTHP process red ginseng were similar to black ginseng. The present results suggest that the HTHP process is available for the development of value-added red ginseng products.

• Korean Journal of Food Science and Technology
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• v.45 no.5
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• pp.550-556
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• 2013

Reflux extraction properties of Schisandra chinensis were investigated with different extraction conditions of ethanol concentration (0-99%), extraction time (2-8 h), and extraction temperature ($40-100^{\circ}C$). Different chemical properties, such as reducing sugars (RS), titratable acidity (TA), Hunter's color values, total phenolic compounds (TPC), and antioxidant activity (DPPH and ABTS assays) were analyzed for the corresponding extracts. The results showed that RS and TA increased as the extraction temperature increased. For each parameter, the maximum value was achieved, when extraction was carried out with 50% ethanol for 8 h at $100^{\circ}C$. Redness ($a^*$) of the extract decreased as all 3 extraction parameters were increased. TPC increased significantly as the extraction time and temperature increased; further, the highest TPC was achieved, when extraction was carried out with 50% ethanol. The same tendency was observed for DPPH and ABTS radical scavenging activities. The highest TPC and antioxidant activity were obtained, when extraction was carried out with 50% ethanol for 4-6 h at $60-80^{\circ}C$, respectively.

• Journal of the Korean Wood Science and Technology
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• v.39 no.4
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• pp.291-302
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• 2011

The study was to investigate whitening and antioxidation effects by determining the tyrosinase inhibition activity, DPPH radical scavenging and superoxide dismutase like activity of essential oils from Cryptomeria japonica and Chamaecyparis obtusa. The aim of the present study was to suggest preliminary data for research whitening and anti-oxidant effects material of C. japonica and C. obtusa essential oils and confirm supplementary worth of natural volatile organic compounds (nVOCs). Essential oils of C. japonica and C. obtusa leaves were extracted by steam distillation method of clevenger type, and nVOCs were extracted by high-temperature reactor for utilizing nVOCs condensates released during drying of C. japonica and C. obtusa at 80, 100, and $120^{\circ}C$ temperature conditions, respectively. In the activity of whitening and antioxidation, C. japonica oil was more effective than C. obtusa oil. nVOCs of C. japonica and C. obtusa showed highly activity of tyrosinase inhibitory at higher temperature. Antioxidation activity only shown on nVOCs of C. japonica produced at $120^{\circ}C$.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.5
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• pp.713-722
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• 2011

This study was conducted to monitor the quality characteristics of Acai (Euterpe oleracea Mart.) ethanolic extracts by a response surface methodology. The independent variables in the extraction experiments were ethanol concentration (0~100%), extraction temperature ($35{\sim}95^{\circ}C$), and ratio of solvent to sample (10~30 mL/g). The coefficients of determinations ($R^2$) were 0.9596 (p<0.01), 0.9356 (p<0.01), and 0.8842 (p<0.05) for total polyphenol, total flavonoid, and electron donating ability, respectively. The electron donating ability and nitrite scavenging effect improved with an increase in ethanol concentration as opposed to extraction temperature. Anthocyanin content with extraction conditions was 74.421~291.841 mg/L and the coefficient of determinations ($R^2$) was 0.9792 (p<0.01). ORAC (oxygen radical absorbance capacity) with extraction conditions was 137.73~562.94 ${\mu}moles$ TE/g and increased with an increase in ethanol concentration and a decrease in the ratio of solvent to sample content. Estimated conditions for maximum extraction including yield, total polyphenol, total flavonoid, electron donating ability, anthocyanin content, and ORAC were 28~58% for ethanol concentration, $60{\sim}68^{\circ}C$ for extraction temperature, and 10~12 mL/g for ratio of solvent to sample.

• Journal of Aquaculture
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• v.19 no.1
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• pp.57-63
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• 2006

This study was conducted to investigate the effects of dietary supplementation of spirulina (SPI) and asthaxanthin (AST) on growth performance and antioxidant activity in juvenile olive flounder (Paralichthys olivaceus) in low temperature season. Total 180 fish ($27.8{\pm}0.3g$, average weight ${\pm}S.D.$) were randomly divided into 12 groups, and 3 groups were fed one of four isonitrogenous (52% CP) and isocaloric $(18.3\;MJ\;kg^{-1})$ diets containing no SPI and AST, 0.5% SPI, 0.5% AST, and 0.5% each SPI and AST (designated by diets Control, SPI, AST and SPI+AST, respectively). After 6 weeks of feeding trial, the growth performance, feed utilization, whole body composition and survival of fish were not significantly affected by the experimental diets. There were no significant differences in hematocrit, hemoglobin, alanine aminotransferase and aspartate aminotransferase of fish fed all the experimental diets. The DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging assay indicated numerically increased antioxidant activity in liver of fish fed the SPI diet compared to that of fish fed the control diet, even though it was not significant. The present study shows that a low level (0.5%) of dietary supplementation of SPI and/or AST does not affect growth and feed utilization and intake of juvenile olive flounder in low temperature season.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.637-644
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• 2013

This study was conducted to obtain the baseline data for fermented tea with King oyster (Pleurotus eryngii) mushroom mycelium as well as to investigate the possibility of development for deodeok processing products. For this research, the physicochemical properties and antioxidant activity for fermented tea were confirmed by different roasting temperatures and roasting times. The results of the physicochemical properties, browning, turbidity, reducing sugar, total polyphenol and total flavonoid contents, were increased with increasing roasting temperature and roasting time, whereas the pH was decreased. The results of the antioxidant activity test of fermented tea, DPPH radical-scavenging activity, FRAP and reducing power, were increased with increasing roasting temperature and roasting time. The preference of fermented tea was confirmed as being the highest when roasted at $180^{\circ}C$ for 30 min. Although fermented tea did not have a unique flavor of mushroom and burnt flavor, it had strong color, flavor and taste. For this reason, fermented tea production for high content of functional materials and high preference is possible by roasting at $180^{\circ}C$ for 30 min. As for the results of this study, the physical properties of fermented deodeok were relatively stable on high temperature exposure and furthermore, the development of a variety of foods will be possible because fermented deodeok has an antioxidant capacity.