• Korean Journal of Medicinal Crop Science
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• v.24 no.4
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• pp.294-302
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• 2016

Background: Crop rotation plays an important role in improving soil chemical properties, minimizing the presence of disease pathogens, and assists in neutralizing autotoxic effects associated with allelochemicals. Methods and Results: Five rotation crops of sudan grass, soybean, peanut, sweet potato, and perilla were cultivated for one year with an aim to reduce yield losses caused by repeated cropping of ginseng. In 2-year-old ginseng grown in the same soil as a previous ginseng crop, stem length and leaf area were reduced by 30%, and root weight per plant was reduced by 56%. Crop rotation resulted in a significant decrease in electrical conductivity, $NO_3$, and $P_2O_5$ content of the soil, whereas organic matter, Ca, Mg, Fe, Cu, and Zn content remained-unchanged. Soil K content was increased following crop rotation with sudan grass and peanut only. Rotation with all alternate crops increased subsequent ginseng aerial plant biomass, whereas root weight per plant significantly increased following crop rotation with perilla only. A significant positive correlation was observed between root rot ration and soil K content, and a significant negative correlation was observed between ginseng root yield and the abundance of actinomycetes. Crop rotation affected the soil microbial community by increasing gram negative microbes, the ratio of aerobic microbes, and total microbial biomass whereas decreases were observed in actinomycetes and the ration of saturated fatty acids. Conclusions: In soil exhibiting crop failure following replanting, crop rotation for one year promoted both soil microbial activity and subsequent ginseng aerial plant biomass, but did not ameliorate the occurrence of root rot disease.

• Journal of the Korean Society of Food Culture
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• v.13 no.3
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• pp.191-196
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• 1998

The influence of organic acid dips on the quality properties, color, cooking quality, textural and sensory properties, and reducing microbial population of LL(Long Life) noodles was studied. The contents of organic acid used were 0.2% based on flour weight and LL noodles were treated by dipping in pH $2.5{\pm}0.1$ for $60{\sim}90sec$. The whiteness of LL noodles treated with dl-malic acid was higher than that of others. The shear extrusion force and hardness of LL noodles treated with dl-malic acid were shown much higher value than those of others except treated with dl-malic acid. acetic acid(=1:1). At cooking quality examination of LL noodles treated with organic acids, weight of cooked LL noodles treated with dl-malic acid was decrease but volume was appeared in vice versa. Extraction amounts of LL noodles treated with dl-malic acid, dl-malic acid : acetic acid(=1:1) during cooking were much smaller than those of others. Total counts of microorganism of LL noodles treated with dl-malic acid,dl-malic acid. acetic acid(=1:1) were disappeared during storage at $30^{\circ}C$ but treated with latic acid, acetic acid were increase during storage. Sensory properties of cooked LL noodles which was treated with dl-malic acid showed quite acceptable.

• Food Science of Animal Resources
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• v.21 no.4
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• pp.337-343
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• 2001

Changes of Physicochemical compositions in domestic broiler chickens of different marketing standard range from 5ho (Korean traditional weight unite for chicken) to 16ho were assessed. The moisture contents of chicken breast were 74.00 ∼ 76.15% and there were no significant trend with weight difference. The chicken breasts of the light weight range(5ho∼8ho) contained high fat contents of 2.35∼2.78%. The chicken breasts of the heavy weight range(12ho∼16ho) contained low fat contents of 0.47 ∼0.66%. The chicken breasts of the heavy weight range had more protein contents than those of the light weight range. The chicken breast of the light weight range showed low Warner Braztler shear force (WBS) values when compared to those taken from chicken of the heavy weight range. However. there was no significant differences in water ho1ding capacity (WHC ) and cooking loss(p>0.05). In meat color the L* values (lightness) were 61.83∼71.33 and there were no significant differences for samples in different weight range except 5ho and 13ho. The b* valuers (yellowness) were 1.73 ∼6.79 and the values decreased with increasing chicken weight. In mineral composition. calcium and iron contents were decreased with increasing chicken weight. Phosphate, potassium and magnesium contents increased as weight ranges increased. The thigh meat separated from 11ho to 16ho had a similar tendency. In chemical composition(%). WBS, WBC. cooking loss, meat colors and mineral contents, compacted to breast in the same weight ranges. The results from this study would provide a basic information for establishment of marketing standard of chicken.

• Journal of the Korean Society of Safety
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• v.26 no.4
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• pp.47-58
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• 2011

Halogen free intumescent flame retardants(IFRS), such as the mixture of melamine phosphate(MP) and char forming agents(pentaerythritol(PER), di-pentaerythritol(DiPER), tris(2-hydroxyethyl) isocyanurate(THEIC)), were prepared and characterized. Polypropylene(PP)/$IFR_S$ composites were also prepared in the presence of ethylene diamine phosphate(EDAP) as a synergist and used into flame retardant PP powder coatings. Thermoplastic PP powder coatings at 20 wt% flame retardant loading were manufactured by extruded and then mechanical cryogenic crushed to bring them in fine powder form. These intumescent flame retardant powder coatings($IFRPC_S$) were applied on mild steel surface for the purpose of protection and decorative. It is a process in which a $IFRPC_S$ particles coming in contact with the preheated mild steel surface melt and form a thin coating layer. The obtained MP flame retardant was analyzed by utilizing FTIR, solid-state $^{31}P$ NMR, ICP, EA and PSA. The mechanical properties as tensile strength, melt flow index(MFI) and the thermal property as TGA/DTA and the fire safety characteristics as limiting oxygen index(LOI), UL94 test, SEM were used to investigate the effect of $IFRPC_S$. The experimental results show that the presence of $IFR_S$ considerably enhanced the fire retardant performances as evidenced by the increase of LOI values 17.3 vol% and 32.6 vol% for original PP and $IFRPC_S$-3(PP/MP-DiPER/EDAP), respectively, and a reduction in total flaming combustion time(under 15 sec) in UL94 test of $IFRPC_S$. The prepared $IFRPC_S$-3 have good comprehensive properties with fire retardancy 3.2 mm UL94 V-0 level, LOI value 32.6%, tensile strength $247.3kg/cm^2$, surface roughness Ra $0.78{\mu}m$, showing a better application prospect. Through $IFRPC_S$-2(PP/MP-PER/EDAP) and $IFRPC_S$-3 a better flame retardancy than that of the $IFRPC_S$-1(PP/MP/EDAP) was investigated which was responsible for the formed more dense and compact char layer, improved synergy effect of MP and PER/DiPER.

• Current Research on Agriculture and Life Sciences
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• v.20
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• pp.55-63
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• 2002

This experiment was to know properties of Sericin Jam that development, growth of silkgland, content of sericin and composition of amino acid in hemolymph. The characters of Sericin Jam can he seen form this experiment. Hatching ratio was 85% in Sericin Jam and 95% in Jam 120. Especially hatching period of Sericin Jam was longer than Jam 120 and also hatching of Sericin Jam was ununiform. The larval duration of Sericin Jam was 20 days and 23 hours, and Jaw 120 was 21 days and 22 hours. In Sericin Jam, middle silkgland contain a great p arts in silkgalod and posterior silkgand is short and no curves. The period of mounting to emergence was 12 days in Sericin Jam. The period of pupa was 7day. It is property of Sericin Jam that the period is short. Cocoon was very thin and light in Sericin Jam. Weight of cocoon shell of Sericin Jam is 2.7cg. The sericin protein quantity was 100% in cocoon shell of Sericin Jam, about 28% in cocoon shell of Jam 120, however the sericin ratio per Sericin Jam cocoon was 34.6% compare to cocoon shell of Jaw 120 in sericin protein quantity. The amino acids in hemolymph of Sericin Jaw was much hidtidine, lysine, glut amic acid. And the amount of almost amino acids were increased depends upon development at t he 5th instar.

• Restorative Dentistry and Endodontics
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• v.34 no.2
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• pp.130-136
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• 2009

The aim of this study was to develop a method for measuring the slumping resistance of flowable resin composites and to evaluate the efficacy using rheological methodology. Five commercial flowable composites (Aelitefil flow:AF, Filtek flow:FF, DenFil flow:DF, Tetric flow:TF and Revolution:RV) were used. Same volume of composites in a syringe was extruded on a glass slide using a custom-made loading device. The resin composites were allowed to slump for 10 seconds at $25^{\circ}C$ and light cured. The aspect ratio (height/diameter) of cone or dome shaped specimen was measured for estimating the slumping tendency of composites. The complex viscosity of each composite was measured by a dynamic oscillatory shear test as a function of angular frequency using a rheometer. To compare the slumping tendency of composites, one way-ANOVA and Turkey's post hoc test was performed for the aspect ratio at 95% confidence level. Regression analysis was performed to investigate the relationship between the complex viscosity and the aspect ratio. The results were as follows. 1. Slumping tendency based on the aspect ratio varied among the five materials (AF

• Journal of Life Science
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• v.28 no.11
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• pp.1369-1378
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• 2018

Prunus mume Siebold & Zucc., a member of the Rosaceae family (called Maesil in Korea), has been widely distributed in East Asia, e.g. Korea, Japan and China, and its fruit has been used as a traditional drug and health food. In this study, we evaluated physicochemical properties and physiological activities of condensed Prunus mume juice treated with pectinase (PJ). The values of total acidity, pH, sugar contents, turbidity moisture content of the PJ were 35.81%, 2.73, $54.36^{\circ}Brix$, 2.75 and 51.32%, respectively. The PJ had effective DPPH radical scavenging activity, reducing power effect, $H_2O_2$ scavenging activity and ${\beta}$-carotene bleaching effect. DPPH radical scavenging activities of PJ was 46.31%; their reducing power ($OD_{700}$) was 1.80; $H_2O_2$ scavenging activity of PJ was 91.62%; and ${\beta}$-carotene bleaching effect of PJ was 73.02%. Also, PJ showed effective levels of ${\alpha}$-glucosidase inhibition activity. The cell viability was measured by SRB assay. The PJ significantly decreased the cell viability of mouse melanoma cells (B16) and human melanoma cells (SK-MEL-2 and SK-MEL-28) in a dose-dependent manner, however, there was no effect on human keratinocyte HaCaT. In morphological study, PJ-treated SK-MEL-2 cells showed distorted and shrunken cell masses. Total polyphenol contents and total flavonoid contents of PJ were 588.31 mg% (gallic acid equivalent) and 860.45 mg% (rutin equivalent). The antiproliferative effect of PJ seems to be associated with the antioxidant activity of its flavonoid and polyphenol contents. In conclusion, PJ may be beneficial in development of a functional food material.

• The Korean Journal of Food And Nutrition
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• v.26 no.1
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• pp.85-91
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• 2013

For shelf-life improvement of the domestic peach, a treatment with low dose UV-C (0~3.0 $kJ/m^2$) irradiation was performed and the spoilage rate and changes of physico-chemical and sensory properties of the peach were investigated. Control showed spoilage at day 4, and then 50% of control showed spoilage at day 8. However, samples treated with low dose UV-C showed lower percentage of spoilage than those of control at day 8. Weight changes of control and the samples with UV-C treatment showed no difference during the storage period. There was no difference in pH of samples among the treatments but they were increased by storage time. Hardness of samples was not different among treatments at initial stage of storage after UV-C treatment. However, the hardness of control sample was decreased faster than those of the samples with low dose UV-C treatment after 6 days of storage. No significant changes in lightness, redness and yellowness of the samples by UV-C treatment were observed. The sensory parameters including taste, flavor, and color at initial and during storage period were not different among treatments except for texture and overall acceptance. The scores for texture and overall acceptance of control were decreased faster than those of UV-C treatments during storage. In general, samples treated with low dose UV-C showed higher sensory quality than control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.796-804
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• 2010

This study was conducted to compare and analyze the qualitative property of MLT (mulberry leaf tea) and FMLT (fermented mulberry leaf tea) based on the antioxidant, anticancer activities of various extracts. When the antioxidant activity of MLT and FMLT extracts was evaluated, the electron donating activity was found to increase proportionally as the concentration of each extract increased. In addition, the extract of FMLT showed a higher electron donating activity than that of MLT. Furthermore, the ethanol extracts showed the highest electron donating ability. When the SOD activity was evaluated, it was also found to increase proportionally with the concentration of each extract. Furthermore, the SOD activity of the ethanol extract group was the highest, whereas the SOD like activities of both MLT and FMLT were similar. When nitrite decomposition was evaluated for each pH, the highest value was observed at pH 1.2. Finally, the nitrite deleting ability was the highest for the ethanol extracts. When each extract of MLT and FMLT was analyzed in vitro for anticancer effects, they were found to decrease the number of cancer cells proportionally as the concentration of extract increased for both HeLa cells and MCF-7 cells. Furthermore, FMLT was found to exert a greater inhibition of cancer cells than MLT. Among the extract groups, the ethanol extract induced the greatest inhibition of the development of cancer cells, and these effects were greater against MCF-7 cells than HeLa cells.

• Korean journal of food and cookery science
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• v.24 no.6
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• pp.905-911
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• 2008

Dried and roasted Gugija (Lycii fructus) were extracted with water, 50% ethanol and 100% ethanol, after which the physico-chemical properties of the extracts were evaluated. The extraction yield was higher when using water for the extraction solvent than when the other solvents were used, while the water extract of roasted Gugija had the highest yield. Furthermore the pH of the extracts increased as the ethanol concentration increased, and the pH of dried Gugija was higher than that of roasted Gugija when extracted using the same extraction solvent. The sugar concentrations of the extracts from dried and roasted Gugija were $15.0{\sim}20.1\;%Brix$ and $18.0{\sim}21.2\;%Brix$, respectively. The total polyphenol contents of the extracts from the dried and roasted Gugija were $6.9{\sim}19.0\;mg/g$ and $12.4{\sim}15.8\;mg/g$, respectively. Dried Gugija extract with water had a higher the total polyphenol contents than the other extract. The total polyphenol contents of roasted Gugija extracts were higher than those of dried Gugija, when using 50% or 100% ethanol for extraction solvent. The electron donating ability and total antioxidant activity of dried Gugija were $67.6{\sim}87.7%$ and $58.6{\sim}85.0%$, respectively, whereas those of roasted Gugija were $84.7{\sim}89.8%$ and $80.6{\sim}83.7%$, respectively. Dried and roasted Gugija extracts were higher electron donating ability and total antioxidant activity, when using water, and 50% or 100% ethanol, respectively. The predominant amino acid in all extracts was threonine. The essential amino acids constituted approximately $44.9{\sim}63.6%$ and $45.4{\sim}59.0%$ of the total amino acids of extracts from the dried and roasted Gugija, respectively. Finally, the total polyphenol contents and antioxidant activities showed that optimal extraction solvent would be water, and 50% or 100% ethanol for dried and roasted Gugija, respectively.