• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.05a
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• pp.23.1-26
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• 2003

This study is intended to investigate the properties of early strength development by application of TEA to the field. According to the results, when TEA is added, fluidity is almost same to base concrete, and increases upto aimed slump after field flowing. Setting time does not differ in the case of base and TEA, but is retarded after flowing. The time when compressive strength gains 5 MPa, which side form can be removed, is 23 hours, and so the removal time is shortened by 1hours in comparison with plain concrete. But compressive strength is almost same to that of plain concrete at 28 days. The rebound value of P type schmidt hammer show similar tendency to compressive strength, and the rebound value of structure is higher than that of standard curing specimen due to heat capacity effect and drying by the air outside. Therefore, it is thought that if the rebound value of P type schmidt hammer is controled. by about 26 in consideration of open air environment, it is very effective to determine the removal time of side forms.

• Journal of the Korea Convergence Society
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• v.9 no.7
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• pp.149-154
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• 2018

This article intended to examine the anti-plaque activity of 4 essential oils of Lavender, Tea tree, Eucalyptus, Lemongrass against Streptococcus mutans. In the results of measuring the anti-plaque effect against Streptococcus mutans, Minimum anti-adhesive concentration of Lavender oil was 1.0% and that of Tea tree, Eucalyptus, lemongrass essential oils was 0.5 %. Also, it was confirmed that the essential oils have the effect of inhibiting acid generation by Streptococcus mutans. It was confirmed that pH of the concentration was lowered by the acid generation under the MAC by measuring pH of the solution after incubating Streptococcus mutans and the essential oils in the thermostatic bath varying their concentration. From these results, the essential oils, particularly, Tea tree, Eucalyptus, Lemongrass essential oils are the natural material inhibiting the plaque generation and the potential that they can be used to develop the oral care products was confirmed.

• Journal of Life Science
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• v.12 no.2
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• pp.75-79
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• 2002

Tea catechins, the most important compounds in tea polyphenols, can efficiently scavenge superoxide anion free-radical ($O_2$.), hydroxyl radical. (.OH) The mechanism of scavenging active oxygen free radicals was investigated by ESR spin trapping technique and Chemiluminescence. Results showed that various tea catechins constitute an antioxidant cycle in accordance with the decreasing order of the first reductive potential, and produce the effect of cooperative strength each other. Esterificated catechins could scavenge active oxygen free radicals more effectively than the non-esterificated ones. When.OH and $O_2$.- were scavenged by (-)-epigallocatechin gallate [(-)- EGCG], the stoichiometric factors were 6, and the rate constants of scavenging reaction reached $7.71{\times}10^6$ and $3.52{\times}10^{11}$ L $mmol^{-1}s^{-1}$, respectively. In the mean time, tea catechins could scavenge superoxide anion fiee radical ($O_2$-.) and hydroxyl radical (.OH) in a dose dependent manner. But at higher concentration or pH value, tea catechins can induce the prooxidant.

• Food Science and Preservation
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• v.7 no.2
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• pp.171-176
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• 2000

Drink and tea-bag were processed with safflower seed powder. Drinks were processed with 90$^{\circ}$C hot water extraction. Yield, soluble solid, pH and centrifugation residue of drinks were ranged in 79.2~89.3%, 0.6~0.99%, 5.98~6.40 and 1.00~1.18, respectively. Sensory score of overall acceptance in drinks were highest at that of enzyme treated drink. Tea-bag was processed with roasted safflower seed powder, alone(1.2g) and the mixtured tea-bags were consisted of persimmon leaves, pine needle and angelica gigas powder in same amount, respectively. Teas were prepared with extraction at 80$^{\circ}$C water for 2 min. Soluble solid and sensory evaluation score of teas were the highest when the tea was processed with safflower seed alone.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.297-303
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• 2006

Cuticular waxes on tea (Camellia sinensis L.) loaves consisted mainly of alkanes, fatty acids, primary alcohols, triterpenes, and a group of unknown compounds, dominated by primary alcohols and triterpenes. Tea tree accessions used in this study were M-1, M-2, Sakimidori, and Yabukita. For all accessions, the alkane, fatty acid, and primary alcohol constituents consisted of a homologues series, and the major constituents of primary alcohol class were the C28 and C30 homologues. Triterpenes consisted of friedelin, $\beta-amyrin$, and three unidentified ones and friedelin was the most abundant. Leaf area and the total amounts of cuticular waxes per leaf increased with lower leaf position from the apical bud in Yabukita variety. With different leaf position, total wax amount per unit leaf area on the youngest leaves of P1 (the uppermost leaf position) showed the largest amount $(12.80{\mu}g/cm^2)$, and on mature loaves of P2 to P6 ranged from 7.08 to $7.77{\mu}g/cm^2$, and then on the oldest loaves of P7 (the lowest leaf position) remained at an increased level $(17.53{\mu}g/cm^2)$. During leaf development (lower leaf position), the amount of primary alcohols decreased from P1 to P6 and increased at P7, whereas that of triterpenes increased from P1 to P7. The percentage of each wax class in the total wax amount occurred a decrease in primary alcohol and an increase in triterpene, with leaf age.

• Korean journal of food and cookery science
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• v.4 no.1
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• pp.41-46
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• 1988

Omija tea with a pH range of 2.8~3.0 was stored at $25^{\circ}C$ to study its spoilage due to microbial growth. Titratable acidity was increasing during the storage period in the tea stored with the Omija fruits but not in removed of the fruits after extraction. Microbial cells began to show up earlier in the tea without the fruits than that with the fruits. Four strains of yeasts and a strain of mold were isolated from spoiled Omija tea. Morphological, cultural and physiological characteristics of yeasts were investigated and the yeasts were identified as Rhodotorula rubra, Saccharomyces kluyveri, Cryptococcus hungaricus and Candida humicola. Morphological characteristics of the isolated mold was observed and the mold was identified as Mucor circinelloides f. janssenii.

• The Korean Journal of Food And Nutrition
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• v.18 no.4
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• pp.325-333
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• 2005

This experiment was carried out to investigate the effect of green tea powder on the growth and acid production of lactic culture in reconstituted skim milk. The supplementation level of green tea powder to reconstituted skim milk was $0.5\%,\;1.0\%,\;1.5\%,\;2.0\%\;and\;2.5\%$. Reconstituted skim milk containing green tea powder was fermented by single or mixed culture of Streptococcus thermophilus, Lactobacillus acidophilus and Lactobacillus casei. Supplementation of green tea powder did not significantly stimulate growth and acid production of Streptococcus thermophilus and Lactobacillus casei. But the growth and acid production of Lactobacillus acidophilus were slightly enhanced by the addition of green tea powder. When green tea powder was added to reconstituted skim milk at the level of $0.5\%\;or\;1.0\%$, all mixed cultures oi lactic acid bacteria showed high number of viable cell count and the acid production than 3 kinds of single cultures. Therefore, it was suggested to manufacture the yoghurt with the addition of $0.5\~1.0\%$ green tea powder and the inoculation of mixed cultures of lactic acid bacteria for on the stimulation of growth of the lactic culture.

• Journal of Ginseng Research
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• v.47 no.6
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• pp.773-783
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• 2023

Background: Gray mold, caused by Botrytis cinerea, is one of the major fungal diseases in agriculture. Biological methods are preferred over chemical fungicides to control gray mold since they are less toxic to the environment and could induce the resistance to pathogens in plants. In this work, we try to understand if ginseng defense to B. cinerea could be induced by fungal hypovirulent strain △BcSpd1. BcSpd1 encodes Zn(II)₂Cys₆ transcription factor which regulates fungal pathogenicity and we recently reported △BcSpd1 mutants reduced fungal virulence. Methods: We performed transcriptomic analysis of the host to investigate the induced defense response of ginseng treated by B. cinerea △BcSpd1. The metabolites in ginseng flavonoids pathway were determined by UPLC-ESI-MS/MS and the antifungal activates were then performed. Results: We found that △BcSpd1 enhanced the ginseng defense response when applied to healthy ginseng leaves and further changed the metabolism of flavonoids. Compared with untreated plants, the application of △BcSpd1 on ginseng leaves significantly increased the accumulation of p-coumaric acid and myricetin, which could inhibit the fungal growth. Conclusion: B. cinerea △BcSpd1 could effectively induce the medicinal plant defense and is referred to as the biological control agent in ginseng disease management.

• The Korean Journal of Food And Nutrition
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• v.18 no.1
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• pp.48-53
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• 2005

Herbs and yucca(Yucca shidigera) are widely used a source of tea and otherwise such as botanical medicine, essential oil for perfumes, cosmetics, and food spices. This study was carried out to investigate the characteristics of herb tea prepared with lemon verbena, spearmint, apple mint, Korea mint, rosemary, pineapple sage, Chrysanthemum indicum, stevia, lavender, lemon balm cultivated in Korea and effects by addition of yucca. Approximate composition of yucca were as follows: moisture 5.88%, crude protein 5.46%, crude fat 0.69%, crude ash and 7.59%. pH of herb tea mixed yucca at 80℃ was decreased in lemon verbena, spearmint, apple mint, Korea mint, and rosemary in comparison herb tea alone, but soluble solids were similar in two tea. In the result of sensory test, herb tea and herb tea mixed Yucca were not difference with a few exceptions. pH of mentha(Korea mint) tea by addition of yucca was decreased according to increment amount of yucca. The sensory evaluation score of mentha tea by addition of yucca were increased when the tea was processed with 0.01∼0.04% yucca.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1279-1285
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• 2010

This study was conducted to investigate the effects of green tea or coffee consumption on the serum lipids profiles. This study analyzed data of 1,343 participants (753 males and 590 females) among the people who underwent medical check-up. The subjects were divided by three groups as pattern of green tea or coffee consumption. Anthropometric measurements, biochemical analysis and nutrient intake using a food frequency questionnaire were performed. There were no significant differences among groups in height, % body fat, waist circumference, and body mass index. There was no significant difference among groups in energy intake. Fat intake was significantly higher in green tea and coffee group than the control group in men subjects. The intakes of dietary Fe, vitamin A, $\beta$-carotene, and folate was the lowest in coffee group (p<0.05). The intakes of dietary fat was the highest in coffee group in male subjects (p<0.05). Serum concentrations of total cholesterol and LDL-cholesterol were green tea< control< coffee group in order by multivariate analysis after adjusting for confounding factors. The serum concentrations of total cholesterol and LDL-cholesterol were significantly lower in green tea group than coffee group by multivariate analysis after adjusting for confounding factors (p<0.05). However, there was no significant difference in the serum concentrations of total cholesterol and LDL-cholesterol between green tea and control group. These results suggest that green tea consumption didn't show positive effects in preventing hyperlipidemia but coffee consumption showed negative effects in hyperlipidemia.