• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.3
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• pp.291-306
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• 1984

The possibility of formation of carcinogenic N-nitrosamines such as nitrosodimethylamine(NDMA), nitrosodiethylamine (NDEA) and nitrosopyrolidine (NPYR) during the fermentation of Kimchi was investigated. Three different types of Kimchi, formulated with chinese cabbage, red pepper powder and garlic, with or without one of both fermented shrimp and anchovy juice, were cured for 75 days at $5^{\circ}C$. The changes in contents of nitrates, nitrites, pH, ascorbic acid, secondary amines, trimethyl-aminoxide (TMAO), trimethylamine (TMA) and NDMA were analyzed periodically during the fermentation. TMAO, TMA. DMA, nitrate, nitrite and ascorbic acid were analyzed by colorimetric methods, and NDMA, NPYR and NDEA were determined by the method of GLC-TEA. Although the total secondary amines markedly increased, no significant changes in the levels of TMAO and TMA were observed during the fermentation Kimchi added with fermented shrimp or anchovy juice. The predominating component of secondary amines was confirmed to be dimethylamine by means of nitrosating technique coupled with gas chromatography. No appreciable increase in the level of nitrites was appeared although nitrate level in the Kimchi apparently decreased. Non detectable or trace level of nitrosamine formation was detected whereas the nitrates fairly decreased during the fermentation of Kimchi. This could be explained by the fact that the lack of nitrites was resulted in the system due to rapid consumption of nitrites formed from nitrates by the reactions with ascorbic acid and amino acids which have been known as inhibitors of nitrosation reaction.

• Food Science and Preservation
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• v.21 no.4
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• pp.587-592
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• 2014

Brassica spp. vegetables have been known to have biological activities such as anti-cancer and anti-inflammatory activities. In this study, we investigated the in vitro physicochemical characteristics and antioxidant activities of commonly used Brassica spp. sprout vegetables such as kohlabi (Brassica oleracea var. gongyloides), red radish (Raphanussativus L. var. sativus), broccoli (B. oleracea var. italica), cabbage (B. rapavar. glabra Regel), rape (B. napus), radish (R. sativus), and tatsoi (B. campestris var. narinosa) sprouts. Our results showed that the vegetables with the highest total phenolics contents were the radish sprout ($24.40{\pm}1.24mg\;TAE/g$) and kohlabi sprout extracts ($23.97{\pm}0.46mg\;TAE/g$). Furthermore, the vegetable with the highest total flavonoid content was the radish sprout extract ($15.30{\pm}1.35mg\;CE/g$). However, the kohlabi sprout extract showed the highest DPPH radical scavenging value ($IC_{50}=1.95mg/mL$) and ORAC value (79.03 mM TE/g). In addition,the six kinds of Brassica spp. sprout vegetable extracts, except tatsoi, significantly inhibited the reactive oxygen species (ROS) production and showed that intracellular oxidative stress is closely related tothe accumulation of differentiated adipocytes and fat during the adipogenesis of 3T3-L1 preadipocytes. These results suggest that Brassica spp. sprout vegetables, especially kohlabi and radish sprout extracts, can be used to develop natural antioxidants.

• Journal of Nutrition and Health
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• v.31 no.7
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• pp.1151-1157
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• 1998

Many type II diabetic patients use folk remedies to. treat diabetes in Korea. The physiology, pathology, usage, and prescriptions of folk remedies are not well established, and the effects of those remedies were handed down by word of mouth of experienced persons. Most of these remedies can cause unexpected side effects if consumed in large amounts since patients lack scientific backgrounds and the precise effects as well as the possible side effects have not been proven. The purpose of this survey was to investigate the prevalence of diabetic f31k remedies used by adult diabetic patients who use diet therapy to treat diabetes. This information can be used for a basic scientific approach to diabetic f31k remedies. The results of the survey were as follows : 1) Thiry-nine patients(53.4%) out of a total of 75 patients, answered that they used folk remedies. 2) There were 54 kinds of folk remedies f3r diabetes, and the most popular ones are silk worm powder, red jinseng, silkworm pupa, raw lentils, and cabbage, that to accounted for 97.4% of the experienced group. 3) The most common way to be exposed to folk remedies were recomnendations by friends and relatives, and through the mass communication such as TV, newspaper, magazine. As fir as the effects of the flok remedies goes, 17% answered that they experienced positive effects in controlling blood glucose levels and 5.7% reported negative effects. Moreover, 17.1% answered that they experienced side effects like stomach ache and bloating. 4) The 82.9% of the experienced group answered that they used silkworm powder, which was the most popular one in folk remedies. 5) 75% of the experienced group patients showed positive responses to folk remedies, saying that they will try new folk remedies if introduced. Even 66.7% of inexperienced group showed their interest saying that they will try new folk remedies.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.3
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• pp.71-81
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• 2009

Food waste has been actively used as a composting material in order to reduce the environmental pollution load and to enhance the recycling of resources. In this study, the longterm effects of continuous application of food waste compost to soils on both the crop production and the soil properties were examined to ensure the safety of food waste compost in agricultural use. In addition, we collected the preliminary data for establishing standard application rate of food waste compost for agricultural utilization. Based on conventional nitrogen application rate of chemical fertilizer for crop cultivation, pig manure compost $(24g\;N\;kg^{-1}$, $8g\;P_2O_5\;kg^{-1}$, and $10.4g\;K_2O\;kg^{-1})$ and food waste compost ($20g\;N\;kg^{-1}$, $20.1g\;P_2O_5\;kg^{-1}$, and $6.5g\;K_2O\;kg^{-1}$) were applied to the upland soil in $2{\times}2{\times}2m$ lysimeter in which lettuce (Lactuca sativa var. crispa), Chinese cabbage (Brassica campestris subsp. napus var. pekinensis), red pepper (Capsicum annuum), and potato (Solanum tuberosum) were grown continuously. The crops grown in soils to which food waste compost applied showed better growth responses than the control, whereas some variations were observed in the crops grown in chemical fertilizer treated soils. Continuous application of food waste compost increased the contents of organic matter, nitrogen, and phosphorus, which resulted in improving soil aeration.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.3
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• pp.103-134
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• 1977

The physiological and biochemical role of potassium for upland crops according to recent research reports and the nutritional status of potassium in Korea were reviewed. Since physical and chemical characteristics of potassium ion are different from those of sodium, potassium can not completely be replaced by sodium and replacement must be limited to minimum possible functional area. Specific roles of potassium seem to keep fine structure of biological membranes such as thylacoid membrane of chloroplast in the most efficient form and to be allosteric effector and conformation controller of various enzymes principally in carbohydrate and protein metabolism. Potassium is essential to improve the efficiency of phoro- and oxidative- phosphorylation and involve deeply in all energy required metabolisms especially synthesis of organic matter and their translocation. Potassium has many important, physiological functions such as maintenance of osmotic pressure and optimum hydration of cell colloids, consequently uptake and translocation of water resulting in higher water use efficiency and of better subcellular environment for various physiological and biochemical activities. Potassium affects uptake and translocation of mineral nutrients and quality of products. potassium itself in products may become a quality criteria due to potassium essentiality for human beings. Potassium uptake is greatly decreased by low temperature and controlled by unknown feed back mechanism of potassium in plants. Thus the luxury absorption should be reconsidered. Total potassium content of upland soil in Korea is about 3% but the exchangeable one is about 0.3 me/100g soil. All upland crops require much potassium probably due to freezing and cold weather and also due to wet damage and drought caused by uneven rainfall pattern. In barley, potassium should be high at just before freezing and just after thawing and move into grain from heading for higher yield. Use efficiency of potassium was 27% for barley and 58% in old uplands, 46% in newly opened hilly lands for soybean. Soybean plant showed potassium deficiency symptom in various fields especially in newly opened hilly lands. Potassium criteria for normal growth appear 2% $K_2O$ and 1.0 K/(Ca+Mg) (content ratio) at flower bud initiation stage for soybean. Potassium requirement in plant was high in carrot, egg plant, chinese cabbage, red pepper, raddish and tomato. Potassium content in leaves was significantly correlated with yield in chinese cabbage. Sweet potato. greatly absorbed potassium subsequently affected potassium nutrition of the following crop. In the case of potassium deficiency, root showed the greatest difference in potassium content from that of normal indicating that deficiency damages root first. Potatoes and corn showed much higher potassium content in comparison with calcium and magnesium. Forage crops from ranges showed relatively high potassium content which was significantly and positively correlated with nitrogen, phosphorus and calcium content. Percentage of orchards (apple, pear, peach, grape, and orange) insufficient in potassium ranged from 16 to 25. The leaves and soils from the good apple and pear orchards showed higher potassium content than those from the poor ones. Critical ratio of $K_2O/(CaO+MgO)$ in mulberry leaves to escape from winter death of branch tip was 0.95. In the multiple croping system, exchangeable potassium in soils after one crop was affected by the previous crops and potassium uptake seemed to be related with soil organic matter providing soil moisture and aeration. Thus, the long term and quantitative investigation of various forms of potassium including total one are needed in relation to soil, weather and croping system. Potassium uptake and efficiency may be increased by topdressing, deep placement, slow-releasing or granular fertilizer application with the consideration of rainfall pattern. In all researches for nutritional explanation including potassium of crop yield reasonable and practicable nutritional indices will most easily be obtained through multifactor analysis.

• Journal of Nutrition and Health
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• v.41 no.5
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• pp.439-447
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• 2008

There is a limitation to estimate vitamin $B_{12}$ intake due to lack of data on vitamin $B_{12}$ content in many Korean foods. In this study, vitamin $B_{12}$ content was determined in some soybean or vegetable-fermented foods, edible seaweeds and other frequently consumed foods in Korea by microbioassay using Lactobacillus delbruecki ATCC 7830. The traditional type of Doenjang and Chungkookjang contained 1.85 ${\mu}g/100$ g and 0.69 ${\mu}g/100$ g of vitamin $B_{12}$, respectively, while the factory-type of Doenjang and Chungkookjang contained 0.04-0.86 ${\mu}g/100$ g and 0.06-0.15 ${\mu}g/100$ g. Vitamin $B_{12}$ was not detected in steamed soybeans and Tofu which is a not-fermented soybean product, indicating that vitamin $B_{12}$ in Doenjang and Chungkookjang might be produced during the fermentation process. The Korean-style soy sauce contained 0.04 ${\mu}g$ vitamin $B_{12}$/100 mL, but vitamin $B_{12}$ was not detected in Japanese-style soy sauce and white miso. Commercial Kimchi, a representative Korean vegetable- fermented food, made of Korean cabbage, Yeolmu, or Mustard leaves contained 0.013-0.03 ${\mu}g$ vitamin $B_{12}$/100 g, while Kimchi without red pepper and fermented fish sauce (White Kimchi) did not. Vitamin $B_{12}$ content was very high in some edible seaweeds such as laver (66.76 ${\mu}g/100$ g dry weight) and sea lettuce (84.74 ${\mu}g/100$ g dry weight), and it was 17.12 ${\mu}g/100$ g of dried small anchovy, 1.07 ${\mu}g/100$ g of whole egg, and 0.02 ${\mu}g/100$ g of coffee mix. From these results, it is assumed that Koreans take substantial amount of vitamin $B_{12}$ from plant-origin foods. And, with these data, we will be able to calculate dietary vitamin $B_{12}$ content more correctly than before. In conclusion, soybean-fermented foods, Kimchi, laver and sea lettuce are recommendable as good sources of vitamin $B_{12}$ for vegetarians or Korean elderly on grain and vegetable based diet.