• The Korean Journal of Food And Nutrition
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• v.17 no.1
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• pp.25-31
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• 2004

The quality and sensory characteristics of kimchi during fermentation at 15 $^{\circ}C$ were evaluated. Kimchi was prepared with Chineses cabbage which was brined in 10% salt water added dill hot-water extracts(DK) and stevia hot-water extracts(SK) respectively. The pHs and reducing sugar contents of kimchi were decreased with increasing the fermentation time whereas lactic acid(%) was increased. The pH of DK was lower than control, and the lactic acid(%) contents of DK, SK were equal or higher than control in the first stage of fermentation. Also, the reducing sugar contents of DK, SK were lower than control. These results showed that the fermentation of DK and SK were faster than that of control in the first stage of fermentation. But the lactic acid(%) contents of DK, SK were higher than control after the 12th day of fermentation. It showed that it is possible to extend the preservation of kimchi. With increasing fermentation time, the L value of kimchi juice was increased, and the a value was decreased, and the b value was constant. Especially, the a value of DK, SK was higher than control. It meant that DK, SK kept more carotenoids in kimchi than control. On the 6th day of fermentation, the sensory evaluation analyzed by ANOVA followed Duncan's multiple range test showed that the levels of the green smell and the moldy flavor of DK were significantly lower than control(p<0.05) and the levels of the green smell, the green flavor and the moldy smell of SK were significantly lower than control(p<0.05), too. And the level of overall flavor of DK, SK was higher than control. The most preference among experimental groups was SK and then control, DK. The levels of TBARS of DK, SK were generally lower than control, and the level of TBARS of DK was lower than SK.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.11
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• pp.1351-1357
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• 2007

"Hae-Songi" mushroom is a kind of Hypsizigus marmoreus, one of the edible mushrooms. Powder and hot water extracts of the mushroom fruit-body were investigated for their proximate composition, amino acid contents, ${\beta}-glucan$ contents, total phenolic contents and antioxidant activity. The measured antioxidant activity included free radical scavenging activity against DPPH, reducing power $Fe^{2+}$ chelating ability and SOD activity. Mushroom extracts exhibited in vitro antioxidant activity. This mushroom contained high protein (29%, total amino acid contents 204.86 mg/g), free amino acids (46.53 mg/g) and ${\beta}-glucan$(0.11%). At a concentration of 1% extracts solutions (w/v) according to different extraction times, DPPH free radical-scavenging activities were found to exhibit $89%{\sim}92%$ inhibition. Positive correlations $(R^2=0.9901{\sim}0.7424)$ were found between total phenolic content in the mushroom hot water extracts and their antioxidant activity. In this study, it is demonstrated that "Hae-Songi" mushroom may possess potential for use as a health food, due to theirantioxidant capacity.

• Korean Journal of Food Science and Technology
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• v.49 no.2
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• pp.215-221
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• 2017

The biological activity of water-soluble polysaccharide (WSP) fractions extracted from Cedrela sinensis was examined in this study. Cedrela sinensis was extracted using hot water, ultrasonication, and enzymes (Viscozyme, Shearzyme) and precipitated using ethanol to produce crude polysaccharides. The yield (3.51%) and total polysaccharide content (28.03 g/100 g) of WSP extracted using Shearzyme (WSPs) were highest compared to other extracts. The antioxidant activity of WSP extracted using hot water was highest and had the lowest $IC_{50}$ values in DPPH, ABTS, hydroxyl radical scavenging activity, reducing power, and superoxide dismutase-like activity. Tyrosinase inhibitory activity increased as the concentration increased. All extracts showed higher retardation effects on glucose and bile acid compared to the control; particularly, WSPs showed a similar glucose retardation effect to carboxymethyl cellulose. This study suggests that WSP from C. sinensis can be used as a functional food material.

• Korean Journal of Food Science and Technology
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• v.39 no.5
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• pp.515-520
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• 2007

To establish the roasting conditions of dandelion leaves for the manufacture of processed foods such as beverages and tea, we investigated the physicochemical and sensory characteristics of dandelion leaves and their hot water extracts by roasting treatment. As the number of roasting times increased, the free sugar content of the roasted dandelion leaves decreased, and in particular, free amino acid and total polyphenol content decreased greatly after only 1 roasting treatment. The amino nitrogen and total polyphenol contents of the roasted dandelion leaf hot water extracts also decreased greatly, and their L-, a-, and b-values showed much lower values than those of the raw leaf extracts. However, a greater amount of reducing sugars was extracted in the roasted leaves than in the raw leaves, suggesting that the roasting process allows for easier extraction of the compounds in dandelion leaves. Five sensory characteristics, including astringent taste, bitter taste, peen flavor, burnt taste, and sweet odor, were deduced through quantitative descriptive analysis of the hot water extracts. Among them, astringent taste, bitter taste, and green flavor showed significant differences between roasting treatments. The sensory evaluation results show that as the number of roasting times increased, the palatability of the hot water extracts increased greatly, in terms of color and taste.

• Journal of Korean Society on Water Environment
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• v.26 no.6
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• pp.910-918
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• 2010

In recent years, riparian buffer system has been known as one of the effective best management practices. However, establishment of riparian buffer system in aspect of plant species and its position in the riparian buffer zone has not been investigated due to lack of efficient evaluation method for the analysis of water quality improvement with established riparian buffer system. To solve this problem, the SWAT-REMM prototype was developed by the researchers in Canada. But, SWAT-REMM model can not consider the $NO_3-N$ load into riparian buffer system through subsurface flow. Thus to solved this problem, Fortran code of SWAT-REMM model was modified. This modified SWAT-REMM system was applied to the Bonggok watershed. Three riparian buffer scenarios, 15 m, 10 m, 5 m width for tree and grass, were made to evaluate the effects of riparian buffer system on water quality improvement. Reduction efficiency of T-N by riparian buffer system of 15 m wide was the greatest (6 ~ 37%, depending on subwatershed characteristics) among 3 scenarios. It indicates that the reduction efficiency of T-N load has increasing-tendency, as buffer width increasing. The results obtained from the analysis showed that wide buffer zones are found to be more effective in reducing non-point pollutant than narrow buffer zones in the riparian buffer zone system. Hence, the SWAT-REMM model could be efficiently used for evaluation and design the most effective riparian buffer systems to reduce pollutant loads to the watershed although many limitations still exist in SWAT-REMM model.

• Journal of Food Hygiene and Safety
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• v.31 no.2
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• pp.119-125
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• 2016

Antioxidative components and activities of the extracts from Pleurotus ostreatus extracted at different ethanol concentration were analyzed and their correlation were investigated. Ergothioneine, total phenolic compounds, and flavonoid contents of the extracts from P. ostreatus extracted with hot water (0% ethanol) were the highest ($2.98{\pm}0.05$, $9.51{\pm}0.45$, and $2.83{\pm}0.03mg/g$, respectively) and the contents were decreased according to increase of ethanol concentration for extraction. DPPH and ABTS radical scavenging activities of the extracts from P. ostreatus extracted with hot water were the highest ($80.41{\pm}0.56$ and $91.47{\pm}0.11%$, respectively). FRAP value also showed the highest reducing power by $8.86{\pm}0.33\;FeSO_4\;eq$. mM in hot water extracts. Positive correlations were found between ergothioneine contents and antioxidative active components and antioxidant activity of the extracts from P. ostreatus. Results indicate that hot water extraction was most efficient for the extracts with high antioxidative activities from P. ostreatus.

• Asian Journal of Turfgrass Science
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• v.24 no.2
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• pp.199-204
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• 2010

Much of the coal ash by thermal power plant has gradually been increased, however researches on the recycling of bottom ash has not been investigated enough so far. In this research, the lysimeter test was conducted to find out the possibilities of bottom ash as soil amendment to improve the physiochemical properties of sandy topsoil of turfgrass in golf course. The turfgrass growth test and leaching test were conducted on the lysimeter. The lysimeter columns were manufactured with various topsoil mixing ratios of 0, 10, 20, 30, and 50% of bottom ash with sand. As a result of leachate analysis through the lysimeter column, the higher ratios of bottom ash mixed affect significantly on water holding capacity of topsoil sand media with decreasing of the percolation rate. The results of leachate analysis in every three days interval, the pH of leachate increased with the bottom ash ratios, but the volume of $NO_3$-N, $NH_4$-N and K decreased significantly. However, the level of EC of leachate had constantly maintained. These results indicate that the application of bottom ash may improve turfgrass growth with water holding capability and fertility of sandy topsoil. However, the negative effects of the bottom ash also evaluated by reducing water permeability and solubility of $PO_4$-P by adsorption into soil particles. The results indicates that the reasonable mixing ratio of the bottom ash as soil amendment should be less than 20% (v/v) with sand which has a low water-holding and fertility in golf course topsoil layers.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.323-329
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• 2005

In this paper, performance of a hybrid sequential aerobic-anaerobic natural system was investigated. Continuous aerobic and anoxic conditions were created by alternatively placing waste stabilization pond (WSP) and wale. hyacinth pond (WHP). Two pilot-scale treatment lines were built and operated; The first consists of WSP integrated with WHP and the second of WSP connected with Dark Pond(DP), namely control system ponds which were used to examine the effects of water hyacinth on nitrification and de-nitrification. The overall performance in nitrogen was 86% reduction in WSP-WHP and 36% in WSP-control pond system. Nitrogen was mostly removed by nitrification and de-nitrification which simultaneously occurred in the same water hyacinth ponds. For the de-nitrification, benthic layer was found out to be adequate support as a carbon source. In addition, WSP-WHP system was very effective in reducing phosphorus. Overall P removal efficiency in WSP-WHP is 81%, while it is only 16% in WSP-control. difference in phosphorus reduction between those two systems is thought to be caused by the plants and probably their roots producing extra-cellular materials, but these aspects need to be further studied.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.654-661
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• 2013

The current research is designed to analyze sterilization effects on mulberries in terms of storage temperature and storage period after treating with tap water (TW), electrolyzed water (EW) and aqueous chlorine dioxide ($ClO_2$). The treated $ClO_2$ concentrations are 10, 50, 100 and 200 ppm. In each concentration, the mulberries are soaked for 30 seconds respectively. The sterilization effects are being compared at room temperature ($25^{\circ}C$) and at $4^{\circ}C$, respectively. And the enzyme activity related to quality is also being investigated and analyzed about for browning inhibition effects. Microbial sterilizing power increases more in treating plots with EW and $ClO_2$ than treating plot with TW. Futhermore sterilizing power of $ClO_2$ increased sharply on high concentration treatment plot as well. Sterilization effects of $ClO_2$ during storage time are better at cold temperature. Pictures taken from scanning electron microscope reveal that there are no microbes in sterilizing solutions treatment plots. From measurement of the enzyme activity, it is concluded that activities decrease more in sterilizing solutions treatment plots as comparing with TW treated plot during the time. The amount of total polyphenolics decrease with the time passing and EW and $ClO_2$ treatment shows less contents than TW treatment. Thus, EW and $ClO_2$ treatment of mulberris are considered as method to improve safety by reducing total plate count and to contribute to quality maintenance and to extend storage time.

• 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.