• Korean Journal of Environmental Agriculture
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• v.10 no.1
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• pp.77-83
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• 1991

An animal experiment was performed to investigate the effects of dietary cadmium on growth rates and cadmium accumulations in internal organic tissues and blood by feeding mice with dietary $cdcl_2$ additives and/or brown rice with high cadmium content as during a 12-week feeding period. The results were as follows : Mice weights decreased with increasing levels of dietary cadmium at the end of a 9-week feeding period. The weights of mice organs in the cadmium-free feeding group were higher than in the cadmium-added groups, and the weights of mice organs did not show any significant differences among feeding groups with different levels of dietary cadmium. The concentrations of cadmium in kidney and liver were much higher than in other internal organs and blood, and the next higher concentration was in the heart. The cadmium accumulation in all internal organs and blood increased with increasing dietary cadmium levels, respectively. The ratios of cadmium accumulation in organ tissues and total blood of cadmium-added groups increased with decreasing dietary cadmium levels.

• Food Science and Preservation
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• v.23 no.1
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• pp.117-126
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• 2016

This study was performed to provide information for improving the quality characteristics of tangerine peel Soksungjang. Tangerine peel Soksungjangs were prepared with 10% tangerine peel powder by addition of different koji such as Rhizopus oligosporus (RS, RTS) and Aspergillus oryzae (AS, ATS). As a result, the moisture content was not changed and crude protein content decreased during fermentation in all samples. The pH of RS (Soksungjang manufactured with Rhizopus oligosporus koji) and RTS (Soksungjang manufactured with Rhizopus oligosporus koji and 10% tangerine peel powder) was not changed, whereas pH of AS (Soksungjang manufactured with Aspergillus oryzae) and ATS (Soksungjang manufactured with Aspergillus oryzae koji and 10% tangerine peel powder) decreased rapidly after 10 days of fermentation. The acidity values of all the samples increased during fermentation. The major free sugars were glucose, fructose, and maltose; while, the major organic acids were citric acid, succinic acid, acetic acid, and lactic acid in all the samples. The amino nitrogen content and protease activity were highest in the AS and ATS. Conversely, the reducing sugar content and ${\alpha}$-amylase activity were highest in the RS and RTS. The major free amino acids in all samples were glutamic acid, lysine, leucine, and arginine. Sixty kinds of volatile flavor compounds were identified from all samples; the majority of which were 21 alcohols, 14 hydrocarbons, 5 esters, and others identifies as acids, ketones, and aldehydes.

• Journal of the East Asian Society of Dietary Life
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• v.6 no.1
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• pp.105-114
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• 1996

Certain Fungi Including Aspergillus flavus produce low molecular secondary metabolite that is toxic to human and animals, which have been termed mycotoxin. Given the proper humidity and temperature like summer in Korea, are capable of growing of those hazard fungi and elaborating mycotoxin on almost any organic substrate such as traditional foodstuffs and their raw materials including rice, barley, corn, meju, doenjang and gochujang etc. Until now, some people have examined to isolate various fungi such as Aspergillus sp., Penicillium sp. and Fusarium sp. from traditional foodstuffs and raw materials, and have screened various mycotoxin producing strains. Some mycotoxin contamination such as aflatoxin, ochratoxin, deoxynivalenol (DON) and zearalenone etc. also have been confirmed from similar above samples. But these data are different each other and inconsistent in experimental conditions and methods. Especially, almost experiments have been finished for one time. So more consistent experimental method and data are necessary to evaluate objectiely the safety of traditional foodstuffs subjected to the mycotoxin. For this purpose, we have to apply a new advanced technology to develop more simple and rapid methods for determination of mycotoxin and also have to concentrate our efforts on activation of research and accumulation of technology nth sustaining investment of financial support and enlargement of research installation. With those harmonious efforts, it should be possible to examine continuously nd systematically the mycotoxin contamination in our traditional foodstuffs and to assure the safety of them. Then we can maintain and develop the better traditional foodstuffs suited to internationalization.

• Food Science and Preservation
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• v.20 no.1
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• pp.127-133
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• 2013

The quality characteristics of Hwanggeumju (a type of traditional Korean rice wine), which has been described in an ancient document (Sangayorok), were investigated. During its fermentation, its pH gradually decreased from 4.23 to 3.96); and after four days of fermentation, its sugar content significantly decreased. After seven days, its alcohol content rapidly increased to 15.8 percent. Its major organic acid is lactic acid, but malic, succinic, citric and acetic acid were also detected in it. The free amino acid analysis showed relatively high alanine, arginine, asparagine, glutamic acid and leucine contents. The sensory evaluation resulted in high scores for color, turbidity and taste.

• Korean Journal of Plant Resources
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• v.18 no.2
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• pp.270-278
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• 2005

This experiment was conducted to develop and design a product that is convenient and helpful to both patients and ordinary people who want to maintain their health. In this experimentation, the experimental rat have been given with high fat food to induce Diabetes. Organic brown rice was given as their main energy source and natural complex food, most of materials were freeze-dried, was given to observe its effects on their glucose amount in the plasma. The results are as follows. During 28 days of basal diets, as observing their weight variations, normal group gained weights, but the natural complex food(NCF) groups lost their weights. As comparing the amount of neutral fat levels in the plasma between the diabetes group who just had basal group and one who had NCF, group with NCF groups' level was much lower than the other group who just had basal food. As comparing total cholesterol levels in the plasma, with diabetes group with basal food, $50\%$ and $100\%$ NCF groups' levels were lowered than that group. Regarding HDL-cholesterol level, all NCE groups had around 30mg/dl and there were not much fluctuation among groups. As for LDL-cholesterol level, the $100\%$ NCF group had the lowest level and showed almost the same as the normal group. The amounts of the glucose in the plasma were lowered in all NCF groups. Among those NCE groups, $100\%$ NCF group had 120mg/dl to reach almost the same as the normal group.

• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.204-210
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• 2015

Makgeolli is made from rice or flour, yeast, and nuruk, a fermentation starter. The flavor of makgeolli is affected by sugars, amino acids, organic acids and volatile flavor compounds produced by various microorganisms. In this study, lactic acid bacteria (LAB) were isolated from unsterilized makgeolli samples collected from several provinces in Korea, and then later identified. Under anaerobic conditions, LAB density ranged from $5.0{\times}10^6$ to $1.5{\times}10^8CFU/mL$; yeast density ranged from $2.5{\times}10^7$ to $1.5{\times}10^8CFU/mL$. Of the LAB isolated from makgeolli, 1,126 were analyzed using restriction fragment length polymorphism (PCR-RFLP) analysis of 16S rRNA, which allowed for classification into five groups. Of the 1,126 LABs tested, 130 produced ${\gamma}$-aminobutyric acid (GABA).

• Journal of Life Science
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• v.25 no.4
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• pp.425-432
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• 2015

This study was performed to develop high-value-added biomaterials for health and beauty products. Extracts of ethanol and hot water and their subsequent organic solvent fractions were prepared from Lees of Wookukseng (LW), a commercialized Korean traditional rice wine. We investigated their activities on blood coagulation, platelet aggregation, hemolysis against human red blood cells (hRBCs), and anti-oxidation. The water content, pH and brix of the LW were 80.3%, 3.94 and 13.0°, respectively. The yield of ethanol extraction (6.62%) was 3.15 times higher than that of hot-water extraction (2.1%), and the ethyacetate fraction (EAF) of ethanol extract showed the highest content of total polyphenol (128 mg/g) among the various fractions. In anticoagulation activity assay, the EAF of ethanol extract showed a 15-fold extension in TT, PT, and aPTT, indicating that the EAFs contain various inhibitory substances against thrombin, prothrombin and coagulation factors. In anti-platelet aggregation activity assay, the butanol fraction and water residue of ethanol extract showed significant inhibition activity. The activities were comparable to aspirin, a commercial anti-thrombosis agent. The above extracts and fractions did not show hemolysis activity against hRBC up to 5 mg/ml, and had radical scavenging activity against DPPH anion, ABTS cation and nitrite. Our results suggest that the active fractions prepared from LW, which has no specific usage until now, have a high potential as novel resources for anti-thrombosis agents.

• Applied Biological Chemistry
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• v.40 no.5
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• pp.438-441
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• 1997

The relatedness of naturalized Bradyhizobium japonitum populations with soil physico-chemical characteristics as affected by paddy rice-upland soybean rotation cropping with conventional and none fertilization in Chilgog clay loam soils were determined as follows. The populations of B. japonicum in soils were increased from about $10^1$ in continuous paddy upto $10^1cells/g.soil$ only in one-year rotation of upland use with soybean cropping. Compared to the densities in plots of conventional fertilization, those in none fertilization were high ranging from 1.9 to 10 fold in 2-year upland use rotation and both in 3-year upland use rotation and 4-year upland use, respectively. The populations were positively correlated with soil organic matter $contents(r=0.83^*),\;Ca/K(r=0.74^*),\;and(Ca+Mg)/K(r=0.72^*)$ and were negatively correlated with soil $hardness(r=-0.73^*)$. And the soil populations increased by paddy-upland rotation resulted in superior symbiotic potentials to those in continuous paddy use in terms of nodule mass, nitrogenase activity, and soy-bean shoot dry weight.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.2
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• pp.98-104
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• 2001

Cultivation area of the plastic film-house has been continuously increased with the increase of consumers' income. Intensive land use without fallowing or crop rotation caused severe problem such as salt accumulation in soils and in turn retarded growth and low productivity. This study was carried out to solve them derived from longterm intensive farming practices. Seven farmers who are practicing plastic film-house cultivation were recommended for case study by municipal government and selected for their excellency of cultivation and soil management. The cultivation periods of these systems were in the range of 5 to 40 years in the regions mainly located in alluvial soil cultivated with cucumber, tomato and red pepper. The soils texture of the excellent farmers' fields were silt loam or sandy loam, ranged from 7 to 15 percents of clay contents. Soil bulk density, depth of plowing layer and soil aggregates contents of the farmers' soils were 0.89, 23.1 cm, 61.6% whereas those in neighboring soils were 1.10, 17.8 cm, 54.2 %, respectively. And pH, OM and $NO_3-N$ of the farmers' soils also were better than those of neighboring soils. There was no difference in population densities of nematode between the good farmers' and neighboring soils, but actinomyces and Fusarium densities of recommended farmers' soils were better than neighboring soils. The major farming practices by the good farmers were characterized by deep plowing with flooding, amendment of crude organic matter, and reduction of chemical fertilizer application before transplanting, and also drip irrigation and liquid manure application after planting. They also conducted solar sterilization with or without flooding, removal of plastic films during rainy days and culturing rice or corn as rotation crops to avoid the problems mentioned above.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.5
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• pp.361-368
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• 2000

This study was carried out to investigate the influence of artificial zeolite on the change of temperature, gas emission, water content and chemical properties during the composting process with the mixture of animal feces, broken bark and extruded rice hull. Artificial zeolite was added 0, 0.5, 1, 3 and 5% volume of the raw composting material, and proceeded 1.2m every day with mobile stacking escalator. Temperature was increased, and water content was decreased in the composting pile by addition of artificial zeolite. This caused to accelerate decomposition of organic matter during composting. $NH_3$ was emitted the highest at 6th day after stacking, then decreased gradually. And addition of artificial zeolite caused to decrease greatly in $NH_3$ emission from composting pile. As result of this, content of nitrogen in the compost was increased by addition of artificial zeolite. Emission of $CH_4$ was the highest at early stacking stage, and that was decreased drastically at 8th day. Emission of $CH_4$ was also decreased greatly by addition of artificial zeolite at 5th days after stacking. It may be resulted from adsorption of $CH_4$ into the molecular sieve structure of artificial zeolite and low water content by high temperature fermentation.