• Bulletin of the Korean Chemical Society
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• v.10 no.1
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• pp.1-5
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• 1989

The nonempirical molecular connectivity indexes of a number of mono- and disubstituted purines were calculated. Very good correlations were obtained between anticancer activity (log 1/c) and toxic activity (log 1/) of tIhese compounds and their molecular connectivity indexes and physicochemical constants. Our structure-activity relationship is discussed briefly in relation to theories of general QSAR.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.3
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• pp.54-63
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• 1999

Quantifications of fish farm influences on stream water quality may provide basic informations on watershed management to reduce environmental impact due to fish farm development and to conserve stream water quality in forested watershed area. In this research stream water qualities around (Mt.) Paekun area were monitored by seasons and the following results were obtained. Due to the increase of pH in effluent water from the fish farm it was believed that alkalization of stream water can be accelerated by large scale development of fish farms in the forested watershed area. Negative effects on stream water quality was also observed by indications of increase in electrical conductivity and temperature of effluent water from the fish farm. Decreases of physicochemical indexes such as the amount of dissolved oxygen, percentage of dissolved oxygen and total amount of ion in effluent water from the fish farm were also negative aspects in downstream ecology. It is recommended that water purification system as well as eco-friendly fish farm design be incorporated to large scale fish farm development plan in forested watershed area.

• Culinary science and hospitality research
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• v.14 no.3
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• pp.136-142
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• 2008

This study was conducted to investigate the correlation of the physicochemical quality index(pH, acidity, reducing sugar content and lactic acid bacterial count) and sensory index(sourness) of Kakdugi during the fermentation at 5$^{\circ}C$, 10$^{\circ}C$ and 20$^{\circ}C$ respectively. Also, the relations between physicochemical quality index and overall acceptability were carried out. The pH range, based on the middle sour intensity point of 4.5, was 5.75 at 5$^{\circ}C$ fermentation, whereas that was 4.2 at 10$^{\circ}C$ and 20$^{\circ}C$ fermentation. The pH showing the highest overall acceptability decreased along with increased fermentation temperature. The reduced sugar content decreased rapidly up to 0.9% acidity, but after that, decreased slowly from more than 0.9% acidity at all fermentation temperatures. With increased fermentation temperature, the reduced sugar content showing the highest overall acceptability also showed the decreasing tendency. Change patterns of lactic acid bacterial count and sourness didn't coincided at 5$^{\circ}C$ fermentation, whereas those did at 10$^{\circ}C$ and 20$^{\circ}C$ fermentation. The indexes showing high significant correlations with sourness of Kakdugi fermented at 5$^{\circ}C$ were not pH and lactic acid bacterial count but acidity and reducing sugar content(p<0.05). The sourness of Kakdugi fermented at 10$^{\circ}C$ and 20$^{\circ}C$ showed high significant correlations with all of the physicochemical index(p<0.05).

• Journal of Microbiology and Biotechnology
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• v.30 no.9
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• pp.1310-1320
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• 2020

Low-quality soil for land reuse is a crucial problem in vegetation quality and especially to waste disposal sites in mining areas. It is necessary to find suitable materials to improve the soil quality and especially to increase soil microbial diversity and activity. In this study, pot experiments were conducted to investigate the effect of a mixed material of humic acid, super absorbent polymer and biochar on low-quality soil indexes and the microbial community response. The indexes included soil physicochemical properties and the corresponding plant growth. The results showed that the mixed material could improve chemical properties and physical structure of soil by increasing the bulk density, porosity, macro aggregate, and promote the mineralization of nutrient elements in soil. The best performance was achieved by adding 3 g·kg^-1 super absorbent polymer, 3 g·kg^-1 humic acid, and 10 g·kg^-1 biochar to soil with plant total nitrogen, dry weight and height increased by 85.18%, 266.41% and 74.06%, respectively. Physicochemical properties caused changes in soil microbial diversity. Acidobacteria, Bacteroidetes, Chloroflexi, Cyanobacteria, Firmicutes, Nitrospirae, Planctomycetes, and Proteobacteria were significantly positively correlated with most of the physical, chemical and plant indicators. Actinobacteria and Armatimonadetes were significantly negatively correlated with most measurement factors. Therefore, this study can contribute to improving the understanding of low-quality soil and how it affects soil microbial functions and sustainability.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.1
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• pp.32-40
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• 2001

Quantifications of fish farm influences on stream water quality may provide basic informations on watershed management to reduce environmental impact due to fish farm development and to conserve stream water quality in forested watershed area. In this research stream water qualities around Mt. Paekun area were monitored seasonally and the following results were obtained. Due to the increase of pH in effluent water from the fish farm it was believed that alkalization of stream water can be accelerated by large scale development of fish farms in the forested watershed area. Negative effects on stream water quality were observed by indications of increase in electrical conductivity and temperature of effluent water from the fish farm. Decreases in physicochemical indices such as the amount of dissolved oxygen, percentage of dissolved oxygen, total amount of cation, total amount of anion and total amount of ion in effluent water from the fish farm were also negative aspects in downstream ecology. It is recommended that water purification system as well as eco-friendly fish farm design should be incorporated to large scale fish farm development plan in forested watershed area.

• The Korean Journal of Food And Nutrition
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• v.32 no.4
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• pp.395-400
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• 2019

This study attempts to analyze the physicochemical characteristics of rice flour developed as rice powder for exclusive use, steamed rice cake recipes developed as basic recipefor rice cakes. The study also aims to compare the quality characteristics of steamed rice cakes in an effort to establish the possibilities of developing various rice cake recipes. The moisture content and amylose content increased as the rice powder particles for exclusive use became finer. With regards to water uptake, in the case of the Hungara type, the water uptake increased as rice powder particles increased in size. In the case of the Shingil and commercial types, the water uptake decreased as rice powder particles increased in size, and solubility and swelling force decreased as rice powder particles increased in size. In the case of chromaticity, Sulgidduk made with rice powder for exclusive use the brightness (L value) increased as powder particles became finer and the yellow indexes (b value) decreased, and this was especially pronounced in the Shingil type. The measurements of changes in the mechanical textures of Sulgidduk showed that rice types with larger particles led to lower hardness, cohesiveness, springiness, and chewiness.

• Journal of the Korean Society of Food Culture
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• v.22 no.6
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• pp.813-819
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• 2007

Physicochemical and sensory properties of sponge cakes using 2 kinds of domestic wheat flour(white flour, whole wheat flour) and imported cake flour were investigated. In the proximate analysis, white flour had higher contents of water and protein compared with those of imported flour. Whole wheat flour had the highest contents of protein, lipid and ash. Regarding the batter, imported flour sample showed lower specific gravity and higher viscosity than those of domestic flour sample, implying that there was more air incorporation and higher batter stability. As a result, imported flour batter produced larger cake compared to that of domestic flour batter. But indexes of symmetry and uniformity showed no significant difference among the samples. In textural analysis using rheometer, cakes with imported flour were softer compared with that with domestic flour. In gumminess and brittleness, cakes with domestic white flour showed the highest value while that with the imported flour showed the lowest value. For the color measurements of cake crumb, no significant difference in DE was found among the samples. Regarding the cross-sections of the cake observed using SEM, imported flour produced cake with smaller and more even air cells compared to that with the domestic flour cake. In sensory evaluation, cakes with the domestic white flour showed the highest moistness value. But there was no significant difference in springiness, firmness, adhesiveness and ease of swallow among the samples. In conclusion, cakes with domestic white flour and whole wheat flour were as good as that with imported cake flour for the sponge cake preparation.

• Journal of Animal Science and Technology
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• v.66 no.3
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• pp.614-629
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• 2024

Hanwoo beef is in high demand because of its unique flavor, freshness, and high-fat content. However, the longer rearing period required to enhance marbling in Hanwoo cattle has adverse environmental consequences, such as greenhouse gas emissions and overall rearing costs. To address consumer preferences for leaner and healthier meat, the Korean meat industry has recently introduced Hanwoo heifer meat as an alternative source, but its quality traits are still unclear. Nevertheless, there is a limited body of research exploring the impact of Hanwoo gender (steer, heifer, and cow) and their corresponding slaughter ages on meat quality traits. This study looked into how gender affected the physicochemical and qualitative features of Hanwoo striploin at their respective slaughter ages. Results revealed that cow striploin has higher levels of moisture (66.81%) and protein (20.76%), whereas it contains lower levels of fat (10.66%) and cholesterol (34.66 mg/100 g). Regarding the physicochemical properties, cow striploin exhibited significantly lower shear force, color indexes, and soluble collagen (p < 0.05). However, chondroitin (1.19%) and muscle fiber area (1,545.23 ㎛²) were significantly higher in steer striploin than in heifer and cow (p < 0.05). Cow striploin exhibited significantly higher levels of oleic acid, unsaturated fatty acids (UFAs), and monounsaturated fatty acids (MUFAs) while having lower levels of eicosadienoic acid and atherogenic index compared to the other two groups. Cows and heifers had higher concentrations of amino acid metabolites than striploin from steers. Furthermore, bioactive metabolites such as carnitine and carnosine content were found higher in cow and heifer respectively. Overall, Hanwoo cattle gender influences the qualitative attributes of striploin; nevertheless, compared to steer and heifer striploin, cow striploin is a relatively good source of protein, fatty acid content, and metabolites conducive to a healthy diet.

• YAKHAK HOEJI
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• v.30 no.3
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• pp.128-138
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• 1986

Three newly synthesized alkanol esters of d-2-(6-methoxy-2-naphthyl) propionic acid, NAPROXEN were examined for physicochemical properties and biopharmaceutical characteristics. These esters were very stable in solid state, but more than 90% of these esters were hydrolysed to the parent, naproxen in rabbit's liver hornogenates. They showed higher dissolution rate in the artificial gastric and intestinal juice, and significantly greater partition coefficient in n-octanol, when compared with naproxen. The absorption rate constants of these esters were increased, while the elimination rate constants were decreased, comparing with naproxen. The ulcerogenic doses on gastric and intestinal mucosa were increased remarkably, and the antiinflammatory dose against carrageenininduced edema on rat hind paw was decreased markedly in these esters, and thus the safety indexes of these esters were higher than that of naproxen.

• Analytical Science and Technology
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• v.37 no.5
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• pp.295-305
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• 2024

5-Hydroxymethyl-2-furaldehyde (5-HMF) is considered one of the main quality indexes of various food products. Its metabolism in humans can potentially lead to carcinogenic compounds. Metallic ions such as Zn, Mg, Mn, and Fe have been reported to enhance 5-HMF formation. Recently, studies on adsorbents that can extract specific organic and inorganic substances with one adsorbent have been conducted. However, simultaneous analysis of organic and inorganic materials typically requires distinct pre-treatment and analytical methods, which increase a lot of labor and cost. In this study, hybrid imprinted polymer (HIP) by mixing 5-HMF imprinted polymer (FIP) and zinc ion imprinted polymer (ZIIP) were generated to extract two analytes, Zn ion and 5-HMF, simultaneously. Physicochemical characterization of HIP was conducted by Fourier-transform infrared spectroscopy, scanning electron microscopy, and sorption tests. Extraction conditions including adsorbent mixing ratio, adsorbate mixing range, and equilibrium time were optimized. Freundlich adsorption model was as the best-fitting isotherm model to elucidate the adsorption mechanism. Affinity of Zn ion and 5-HMF on HIP was superior to non-HIP. In conclusion, HIP showed reasonable feasibility that could be used as an adsorbent to be used for simultaneous extraction of organic and inorganic compounds present in the sample.