• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.10 no.1
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• pp.32-44
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• 2000

The practice of welding stainless steel is known to produce various valance states of chromium. $CO_2$ flux cored arc welding on stainless was performed in fume collection chamber. Content of total chromium and hexavalent chromium in fumes, content of hexavalent chromium in total chromium, solubility of hexavalent chromium were investigated. Content of total chromium in fumes increases from 2~3% to 7~9% as a function of input energy, but hexavalent chromium, less than 1.2% in fumes, is not related to input energy. Hexavalent chromium in fumes exists as solubles up to 90%. Content of total chromium in flux cored arc welding fumes and solubility of hexavalent chromium are similar to shielded metal arc welding fumes, but content of hexavalent chromium is similar to metal inert gas welding fumes. These characteristics are relevant to flux of wires and $CO_2$ shielding gas.

• Korean journal of food and cookery science
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• v.15 no.2
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• pp.95-101
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• 1999

This study was carried out to prepare green teas by traditional roasting manufacturing process, Ku Geung Ku Po and to determine the quality charateristics of the green teas by examining the change of their main components induced during this roasting process. The content of total sugars in unroasted tea leaves was 7.82%. Its content of roasted teas was decreased by increasing the number of roasting and there was significantly differences between samples. The content of total sugars in 9th roasted green tea was 3.98%. The total nitrogen contents of green teas produced by this process were 4.96∼6.38%. The more the number of roasting and the less content of tannin in green teas. And the ratio of total nitrogen and tannin in tea leaves 21.97 but its ratio in 9th roasted tea was increased to 45.54. The ascorbic acid in tea leaves consisted in 1,820.3 mg/100g but its content was decreased by increasing the number of roasting process. Whereas the content of caffeine in green teas was not reduced significantly by this traditional method. Of all amino acids, green tea produced by Ku Jeung Ku Po was rich glutamic acid, lysine and aspartic acid. And especially, phenylalanine, which was rarely found in other green teas, was abundant in these green teas. The compositions of glutamic acid and methionine were increased as increasing the number of roasting process but those of aspartic acid and arginine decreased by these processing. The main fatty acids of Ku Jeung Ku Po green tea were linolenic acid, linoleic acid and palmitic acid and the contents of unsaturated fatty acid in green teas were composed over 70% of total fatty acid. And the fatty acid contents in green teas were not affected during Ku Jeung Ku Po's process. The contents of minerals in these teas was rich in the oder of potassuim. magnessuim and calciumim, and these contents were not observed the prominant change during the process.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.990-997
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• 1995

Effect of preparation method on Yulmoo kimchi(watery kimchi prepared with Yulmoo, leaf radish) fermentation was investigated by measuring physicochemical, microbiological and sensory properties for 20 days. Yulmoo kimchi was fermented at 4$^{\circ}C$ after keeping at room temperature(27$\pm$0.5$^{\circ}C$) for 8 hours. Four types(A, B, C, D) of Yulmoo kimchi were prepared. Sample A was made without wheat flour paste and red pepper powder and sample B was made with wheat flour paste. Sample C was made with red pepper powder, and sample D was made with wheat flour paste and red pepper powder. pH was slowly lowered and stabled after 10 days in all samples. Total acid content increased in all samples. Reducing sugar content initially increased and decreased thereafter. Especially, reducing sugar content of sample B increased in the early stage of fermentation and maintained initial reducing sugar content after 20 days. Total vitamin C content reduced during fermentation in all samples. Especially initial total vitamin C content of sample D increased more than those of other samples relatiely. Lightness and yellowness showed no difference, but on the other hand redness increased gradually in all samples. The number of lactic acid bactgeria reached maximum value in 10~13 days with the total cell numbers and gradually decreased thereafter in all samples. The number of lactic acid bacteria and total cell number of sample D was much more than those of any other samples. As a result of the sensory evaluation, Yulmoo kimchi showed significant difference in all characteristics. Sample D showed the highest scores in all characteristics before 10 days of fermentation. However, after 10 days sample B showed the highest scores.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.2
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• pp.162-166
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• 1991

Twenty brands of five different types of deep-fat fried foods including doughnuts, vegetables, fried chicken and french fries were purchased from food stores and fast food restaurants in Daegu city. These sample were analyzed for their total lipid content and fatty acid composition. The total lipid contents of each type of foods were over 20% by weight on an average. One brand of the doughnuts had the highest lipid content of 55.2%. The average polar lipid content of the five different types of samples was approximately 40% of the total lipid content. The fatty acid compositions of the total lipid in the deep-fat fried foods were similar to one another. HTe major fattyacids were oleic acid, stearic acid, linoleic acid in order of content. Minor fatty caids ere myristic acid, palmitic acid, palmitoleic acid, linolenic acid, behenic acid and erucic acid.

• Journal of Applied Biological Chemistry
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• v.65 no.4
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• pp.413-419
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• 2022

The applicability of Brussels sprouts, which are widely cultivated in Jeju, as a functional biomaterial in the cosmetics and food industries is investigated. The active ingredients (total phenols and flavonoids, β-carotene, vitamin C, free sugar, minerals, glucosinolates, and isothiocyanates) and antioxidant activities of 70% ethanol extracts of Brussels sprouts and cabbage were analyzed. The total phenol, flavonoid, vitamin C, and β-carotene contents of Brussels sprouts were approximately 36%, 2.5 times, 2.3 times, and 65% higher than those of cabbage, respectively. The total free sugar content of Brussels sprouts was 58%-72% lower than that of cabbage. The K content was the highest among the other minerals, and there was little difference between the two samples. The Na content was approximately three times higher in cabbage than in Brussels sprouts. The total glucosinolate content of Brussels sprouts was 34.5 mol SE/g DW, twice that of cabbage. The sinigrin content of Brussels sprouts was thrice (10.06 μmol/g DW) that of cabbage. The isothiocyanate (sulforaphane, I3C) content in Brussels sprouts was double that of cabbage. The antioxidant activity of Brussels sprout extract was 2.5 to 2.8 times higher in 1,1-Diphenyl-2-picrylhydrazyl radical scavenging capacity and 3.3 to 3.6 times higher in 2,2'-Azino-bis(3-ethybenzothiazoline-6-sulfonic acid) radical scavenging capacity than those of cabbage extract. These are important basic data for the study of glucosinolates and isothiocyanates, which have anticancer activity, as well as antioxidant-related substances of Brussels sprout, which has high potential for use as a biomaterial in functional foods and cosmetics.

• The Korean Journal of Food And Nutrition
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• v.36 no.5
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• pp.395-402
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• 2023

As the consumption of corn increases, the production of by-products is also increasing. In this study, functional substances and antioxidant activities of corn by-products were investigated to determine their applicability as functional materials. Total polyphenol, flavonoid contents, and ABTS antioxidant activity were the highest in leaves. The total phenolic acid content was the highest in cobs; p-coumaric and ferulic acid were the main components. Phytosterol content in leaves and stems was high at 64 and 50 days after sowing, 261.4 and 274.7 mg/100 g, respectively. β-sitosterol of the leaves and stems was the highest, 149.2 and 138.7 mg/100 g. The total phytosterol content of grains and by-products harvested 106 days after sowing was in the order of: corn silk, husk, grain, leaf, stem, and cob. Among the phytosterols, β-sitosterol was the highest, followed by stigmasterol and campesterol, and the composition was different depending on part. The total phytosterol content was the highest in husk and corn silk, but the stems and leaves, which account for 50% of the total corn biomass, also contained high phytosterol content. Therefore, corn leaves and stems are expected to be used as functional raw materials for the development of functional materials in the future.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.4
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• pp.680-685
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• 1994

Total nitrogen content, proline, free amino acids, sugars, invertase and diastase activities in native bee-honey (NBH) and foregin bee-honey (FBH) harvested from our different areas of Kangwon , Korea were determined. The total nitrogen contents of NBH and FBH were 0.077$\pm$0.033mg% and 0.055$\pm$0.022mg%, respectively. Proline content in NBH was 42$\pm$10mg% and waqs found to be much lower than that in FHB. Phenylalanine and proline were major free amino acids both in NBH and FBH . The content of total free amino acid in FBH were twice as much as that in NBH , however isomaltose content in NBH were almost two times more than that in FBH. Other sugars including fructose, glucos , sucrose and maltose were also analyzed. No differences were found between NBH and FBH in invertase activities, but comparing to these of FBH ,lower values of diastase activity in NBH were observed.

• Journal of Ecology and Environment
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• v.34 no.3
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• pp.251-257
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• 2011

The purpose of this study was to investigate the acclimation responses of Tamarix chinensis to cold stress. We evaluated the acclimation responses by measuring biomass, daily elongation rate, chlorophyll content, and total soluble carbohydrate content. The plant samples comprised leaves from seedlings of 2 different ages (8 and 12 weeks); the leaves were collected 0, 2, and 4 weeks after cold treatment. We found that the cold-treated samples showed reduced daily elongation rates and chlorophyll content. Further, these samples showed more than 8-fold increase in the total soluble carbohydrate content. However, the seedling ages did not have a significant influence on the growth of cold-treated seedlings. On the basis of these findings, we can conclude that T. chinensis seedlings aged less than 1 year old show acclimation to cold stress by accumulating soluble carbohydrates. This study may help us understand how T. chinensis seedlings acclimatize to their first cold season.

• Korean Journal of Food Science and Technology
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• v.53 no.1
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• pp.63-71
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• 2021

In this study, a comparative analysis was carried out between the 'Beta Tiny' and 'TY Nonari' cherry tomato cultivars harvested at the pink and red stages. Samples of the red stage were stored at room temperature for 9 days, during which physicochemical qualities, antioxidant compounds, and activities were measured. As cherry tomato ripening and storage progressed, firmness was reduced, whereas the lycopene content increased. Total phenolic content and antioxidant activity showed no significant changes as ripening and storage progressed; however, total flavonoid content of 'Beta Tiny' showed a significant increase (p<0.05). The main polyphenols in the two cultivars were identified as chlorogenic acid, rutin, and (-)-epigallocatechin gallate, among which chlorogenic acid showed a significant decrease (p<0.05) as ripening and storage progressed. A strong correlation was found between total phenolic and flavonoid content (R=0.744), and ABTS radical scavenging activity (R=0.975). Additionally, a negative correlation was shown by lycopene and chlorogenic acid (R= -0.934).

• Korean Journal of Food Science and Technology
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• v.52 no.6
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• pp.627-631
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• 2020

High amounts of lemon seeds are discarded as by-products of processing industries. It is important to find some measures, whereby they could be used in value-added ways. Although few studies have been conducted on lemon seed oils, no study has been conducted on the nutrient content of lemon seed sprouts. The objective of this study was to investigate the nutritional value and antioxidant potential of lemon seeds and sprouts. The 1,1-diphenly-2-picrylhydrazyl radical-scavenging potential, total polyphenol, and total free amino acid content were higher in the sprouts than in the seeds. Similarly, the content of such mineral elements as Fe, Na, and Zn, increased with germination. However, salicylic acid and total mineral content were lower in the sprouts than in the seeds. The results indicate that lemon seeds and sprouts could be regarded as high-value materials in food and cosmetic industries.