• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.226-230
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• 1994

In order to compare fall cultivars of Chinese cabbage for kimchi preparation, their physicochemical and organoleptic properties during kimchi fermentation were investigated. When physical characteristics of ten fall cabbage cultivars were compared, `Olympic' had the heaviest average weight and `Chungsan' was the longest in total length. They were also analyzed chemically and compared on water content, vitamin C and reducing sugars. `Noranmat' had the highest water content and `Chungsan' had the highest contents of vitamin C and reducing sugar. Kimchi samples prepared with each fall cultivar were fermented at $4^{\circ}C$ for $40^{\circ}C$ Says, of which pHs and total acid contents were measured and sensory characteristics were compared. Their pHs of `Lipdong' and `Taebok' were lowered most slowly and their pHs of all cultivars were lowered to less than pH 4.0 after the storage of 40 days. Their total acid contents of most cultivars were ranged from 0.55 to 0.59% after the same period. It was shown from the result of sensory eva uation that `Karaksin-1' and `Olympic' were considered to be the best among fall cultivars of Crinese cabbage for kimchi preparation.

• Korean Journal of Food Science and Technology
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• v.43 no.3
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• pp.263-270
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• 2011

This study was performed to acquire processing and reducing factors of difenoconazole during ginseng processing, and to establish the maximum residue limits of ginseng and its commodities. Difenoconazole was used in two fields (Wonju and Icheon) containing 6 year old ginseng plants. The amount of residue at Wonju and Icheon were

• Korean Journal of Food Science and Technology
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• v.49 no.5
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• pp.494-501
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• 2017

Waffles with cinnamon powder added in different proportions (0-12% of wheat flour) were baked to investigate the effects of baking on the physicochemical properties and antioxidant activity. Compared with the control without cinnamon, baking loss was lower in waffles with cinnamon, which led to a decrease in waffle hardness. This was attributable to the higher water-holding capacity of cinnamon than wheat flour. With the increase in the amount of cinnamon, the springiness, resilience, and cohesiveness of the waffle decreased, which was thought to result from the decrease in gluten formation by the proportional decrease of wheat flour. The total reducing capacity and DPPH radical scavenging activity of the waffle was significantly increased. This was substantially in agreement with the observations that cinnamon had an appreciable total reducing capacity and radical scavenging activity that were unchanged by heat treatment. This indicates that the antioxidant functionality of cinnamon could be effectively added to thermally processed food.

• Journal of Life Science
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• v.28 no.5
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• pp.540-546
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• 2018

Annona muricata, generally known as soursop, graviola, or sirsak, is native to the warmest tropical areas of North and South America and is now widely distributed throughout tropical and subtropical parts of the world, including India and Nigeria. This study tested the contents of polyphenolic compounds, flavonoids, and minerals, as well as the antioxidative effects of DPPH radical-scavenging activity, Fe/Cu-reducing power, linoleic-acid peroxidation using thiobarbituric-acid (TBA) methods and peroxidation of rat-hepatocyte microsomes, and ${\beta}$-carotene bleaching assay. These were tested with in-vitro experimental models using water, ethanol, and methanol extracts of the Annona muricata leaf (AMl). Water extracts of AMl showed the highest extraction yield (1.76%). The total polyphenol-compound concentration was the highest in the methanol extract of AMl. However, the flavonoids concentration was the highest in the ethanol extracts of AMl. AMlMl major minerals were Ca, K, and Mg. In DPPH radical-scavenging activity, the contents exhibited a strong scavenging effect on the ethanol and methanol extracts of AMl. Additionally, the Fe/Cu-reducing power was strong in ethanol and methanol extracts of AMl. $Fe^{2+}$/ascorbate-induced linoleic-acid peroxidation using TBA methods and auto-oxidation of rat-hepatic microsomes showed strong antioxidative activities in ethanol extracts of AMl. ${\beta}$-Carotene bleaching was also highest in the ethanol extracts of AMl. These results may provide the basic data to understand the chemical characteristics and antioxidative effects of Annona muricata leaf extract for the development of functional foods.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.461-469
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• 2003

Effects of fruit of Lycium chinense (Chinese matrimony vine) on enzyme activities, and microbial and physicochemical properties of kochjuang were investigated during 12 weeks of fermentation. Enzyme activities were higher during middle of fermentation, and protease activities increased as the ratio of L. chinense increased. Facultative anaerobic bacteria counts decreased in L. chinense-added kochujang, whereas viable cell count of yeasts was higher in 1% L. chinense-added kochujang. Consistency of kochujang decreased by addition of L. chinense. Hunter L- and a-values of L. chinense added kochujang were high, causing slight change in total color difference (E) as the ratio of L chinense increased. Moisture contents of kochujang increased during fermentation, whereas water activities decreased. As the ratio of L. chinense increased, water activities increased. Titrable acidities and oxidation-reduction potential increased by addition of L. chinense. Total sugar contents of kochujang decreased rapidly during fermentation, whereas reducing sugar contents increased up to $2{\sim}4$ weeks of fermentation. As the ratio of L. chinense increased, reducing sugar contents decreased. Ethanol contents of kochujang increased during fermentation, with higher values in 3% L. chinense-added kochujang. Amino and ammonia nitrogen contents of kochujang increased L. chinense content increased. After 12 weeks of fermentation, sensory results showed 3% L. chinense-added kochujang showed highest taste and overall acceptability, and color acceptability increased as L. chinense content increased.

• Journal of the Korea Institute of Building Construction
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• v.11 no.6
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• pp.587-596
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• 2011

Ultra rapid-hardening cement is widely used for latex-modified mortar and concrete as repair and finishing material during urgent work. The purpose of this study is to evaluate the improvements in strength made to SBR cement mortars by the adding of various admixtures and by the use of different curing methods. SBR cement mortar was prepared with various polymer-cement ratios, curing conditions and admixture contents, and tested for flow, flexural and compressive strengths. From the test results, it was determined that the flow of SBR cement mortar increased with an increase in the polymer-cement ratio, and the water reducing ratio also increased. The strength of cement mortar is improved by using SBR emulsion, and is strengthened by adding metakaoline. The strength of SBR cement mortar cured in standard conditions was increased with an increase in the polymer-cement ratio, and attained the maximum strengths at polymer-cement ratios of 15 % and 10 %, respectively. The maximum strengths of SBR cement mortar are about 1.8 and 1.3 times the strengths of plain mortar, respectively. In this study, it is confirmed that the polymer-cement ratio and curing method are important factors for improving the strengths of rapid-hardening SBR cement mortar.

• Food Science and Preservation
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• v.11 no.4
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• pp.544-549
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• 2004

Major components and antioxidant activity of fermented tea were investigated. Contents of total flavonoid and total phenol showed the highest score in ethanol extract ($481.4\;{\mu}g/g$ and 33.5 g/100g), respectively. Their contents in hot water extract ($405.7\;{\mu}g/g$ and 23.6 g/100g) were lower than those of the others extracts. However, their contents of ethyl acetate extract($495.2\;{\mu}g/g$, 39.5 g/100g) from fermented tea stored for 1 year had the highest amount among all tested samples. Catechins of fermented tea were found to be EGC, GC, catechin, catechol and EGCG. However, they were not detected in hot water extract. Scavenging activities of DPPH free radical of all extracts from fermented tea were increased in proportion to their concentration and were $72.4\%$ for fermented tea and $80.9\%$ for fermented tea stored for 1 year. Reducing power of ethanol extract at $500\;{\mu}g/mL$ were 0.78 as OD value of 700 nm for fermented tea and 0.88 for fermented tea stored for 1 year, respectively. Antioxidant activities of ethyl acetate extracts at $3000\;{\mu}g/mL$ were $86.6\%$ for fermented tea and $73.7\%$ for fermented tea stored for 1 year, respectively.

• Journal of Life Science
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• v.26 no.9
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• pp.1022-1026
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• 2016

In this study the hot water extract was prepared from Hydrocotyle sibthorpioides (Araliaceae) leaves and stems to study antioxidant activities and lipoxygenase inhibition. The extract showed the protective hydroxyl radical (-OH) which can damage virtually all types of macromolecules: carbohydrates, nucleic acids (mutations), lipids (lipid peroxidation), and amino acids. Hydroxyl radical scavenging activity of H. sibthorpioides was 78.6%. The extract showed strong activity against 1, 1- diphenyl 2-picrylhyorazyl (DPPH) which is a well-known radical and a trap (scavenger) for other radicals. DPPH scavenging activity of leaves of H. sibthorpioides was evaluated at 8.0 mg/ml was 86.0%. Lipoxygenases (LOXs) constitute a heterogeneous family of lipid peroxidizing enzymes capable of oxygenating polyunsaturated fatty acids to their corresponding hydroperoxy derivatives. The inhibitory effect of 15-LOX by H. sibthorpioides was assayed using a Morgan microplate assay. The extract of H. sibthorpioides was 55.5% inhibitory effects on the inhibition of LOX at 8.0 mg/ml. The IC₅₀ values for OH activity, DPPH activity, and LOX inhibition from leaves 5.23 mg/ml, 6.44 mg/ml, and 3.71 mg/ml, respectively. Antioxidative activity assay showed that the water extracts from leaf and stem had a strong reducing power. These results show that H. sibthorpioides has some phytochemical constituents which may be active against the free radicals (OH and DPPH) and lipoxygenase enzyme.

• Food Science and Biotechnology
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• v.15 no.1
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• pp.63-69
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• 2006

The primary objective of this study is to determine whether a diet supplemented with brown rice koji (BRK) results in a reduced stress response in rats and mice. BRK, which has been suggested as a candidate for use as a stress- and fatigue-fighting supplement, was compared with red ginseng extract (RG) for its stress-reducing potential. The animals in this study were divided into no-stress, stress, RG, and BRK groups of 8 to 10 animals each. Stress was induced by means of immobilization (being restrained in plastic tubes for 30 min and electroshock (0.5 mA in mice or 2 mA in rats for 5 min). The no-stress group was not exposed to stress. Rats in the RG group received oral doses of 200 mg RG extract/kg body weight daily. The BRK group was fed a 30% BRK diet and exposed to stress. Animals were given supplements for 7 days before being exposed to stress, and then were given supplements for 5 days with exposure to stress. When the stress exposure ended, the animals were observed for stress-related changes in behavior and their plasma corticosterone levels were measured. BRK supplementation was associated with a partial blockade of the effects of stress on locomotion and elevated plus-maze test results in rats and mice. It was also associated with a partial reduction in stress-induced behaviors such as freezing, burrowing, smelling, face-washing, and rearing. BRK supplementation did not have a significant effect on plasma corticosterone levels, which were increased in the animals exposed to stress (p<0.01). The mice in the RG group received RG in water (2 mg RG/ mL $H_2O$), and the BRK group received a 30% BRK diet (weight) for 7 days. Both groups were evaluated for signs of fatigue. BRK supplementation increased endurance, as indicated by time on the rota-rod, in cold water, and on the horizontal wire. These results suggest that BRK supplementation partially protects the animal from the effects of stress and may also contribute to resistance to fatigue on physical exertion.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.8
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• pp.961-966
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• 2006

This study was worked out to investigate antioxidant activity of solvent extracts from wild grape skin by measuring electron donating ability (EDA), reducing power, superoxide dismutase (SOD)-like activity, thiobarbituric acid reactive substances (TBARS) and nitrite scavenging ability. Total phenolic compound and flavonoids contents were the highest in ethyl acetate extract, $54.4{\pm}1.18\;mg/100\;g$ and $645.1{\pm}5.05\;mg/100\;g$, respectively. The EDA and reducing power of solvent extracts from wild grape skin were proportionally increased with concentration and ethyl acetate extract $(79.2{\pm}0.06%)$ showed the stronger than BHT $(74.1{\pm}0.15%)$ at concentration of $100\;{\mu}g/mL$, especially. SOD-like ability of ethyl acetate $(25.1{\pm}0.41%)$ and butanol $(20.2{\pm}0.13%)$ extracts were stronger than other extracts at concentration of $100\;{\mu}g/mL$. TBARS of ethyl acetate extract was higher than ascorbic acid. Nitrite scavenging ability of solvent extracts from wild grape skin (pH 2.5, $1000\;{\mu}g/mL$) were in order of ethyl acetate $(90.5{\pm}0.75%)$>butanol $(65.9{\pm}2.16%)$>hexane $(58.1{\pm}1.74%)$>chloroform $(55.4{\pm}1.02%)$>water $(40.9{\pm}0.35%)$. Antioxidant activity of solvent extracts from wild grape skin was the highest in ethyl acetate extract from the results of our experiments.