• Biomedical Science Letters
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• v.17 no.1
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• pp.21-25
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• 2011

We have analyzed 11 different commercial brands provided by Daboo Culture and Art Center. This study was carried out to determine the antibacterial activity of water extract from puer tea ingredients against Staphylococcus aureus (S. aureus) and Listeria monocytogenes (L. monocytogenes). Antibacterial activity of the water extracts was shown against S. aureus and L. monocytogenes by paper disc method. In case of S. aureus, antibacterial activity of the extracts appeared as clear inhibitory zone. This antibacterial activity was greater along with pH and showed the highest effect at pH 10. In case of L. monocytogenes, antibacterial activity of the extract appeared as clear inhibitory zone. Some Puer tea appeared to be more powerful in antibacterial activity against S. aureus and L. monocytogenes. The polyphenol compounds were 3.46~8.68%, depending upon samples. In conclusion, puer tea is considered as a good choice for well-being food.

• Korean journal of food and cookery science
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• v.21 no.6 s.90
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• pp.936-941
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• 2005

Green tea was extracted with different solvents such as hot water, varying concentrations of ethanol and carbon dioxide fluid. The carbon dioxide fluid extraction of green tea was a very effective extraction method in terms of antioxidant yield and stability. At pressure of 125kgf, antioxidant extract of green tea produced a yield 1.87 and 2.8 times higher than hot water and $95\%$ ethanol extract, respectively. Antioxidant extract of carbon dioxide fluid was also very stable during 7-day storage at 35?.

• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.842-846
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• 2004

To elucidate quality changes of pine nuts and walnuts coated with green tea extract-containing protein film during storage, pine nuts and walnuts were coated with soy protein isolate (SPI) and zein film containing green tea extract, and stored at $35^{\circ}C$ for 4 weeks. During storage, peroxide, acid, and 2-thiobarbituric acid (TBA) values increased with increasing storage time regardless of treatments. Degrees of lipid oxidation were lowest in protein coating containing green tea extract, followed by protein coating and control. After 4 weeks, for pine nuts, 40, 32, and 21% of peroxide, acid, and TBA values respectively decreased by treatment of zein film coating containing green tea extract compared with control. For walnuts, 29, 24, and 21% of peroxide, acid, and TBA values respectively decreased. With SPI film coating, 41, 36, and 8% of peroxide, acid, and TBA values of pine nuts respectively decreased. For walnuts, 26, 28, and 5% of peroxide, acid, and TBA values respectively decreased by treatment of SPI film coating containing green tea extract.

• Korean journal of food and cookery science
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• v.16 no.1
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• pp.40-46
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• 2000

The sensitivity of various pathogenic bacteria(Listeria monocytogenes, Staphylococcus aureus, Aeromonas hydrophila, Escherichia coli O157:H7 and Salmonella typhimurium) to the pine needle and green tea extracts was tested. Water extract of pine needle(PNW), 70% ethanol extract of pine needle(PNE), water extract of green tea(GTW) and 70% ethanol extract of green tea(GTE) were prepared for the test of antibacterial activty. Tryptic soy broth(TSB) containing 0∼2%(w/v) of pine needle and green tea extracts were inoculated with 10$\^$5/∼10$\^$6/ cells/ml of each bacterium and incubated at 35$\^{C}$ for 24 hours. The standard plate count method was used to measure the inhibitory effect of the extracts. Minimum inhibitory concentration(MIC) and minimum bactericidal concentration(MBC) were derived from the survival curves of pathogenic bacteria. Antibacterial activities of the pine needle and green tea extracts were compared with that of sodium benzoate, a preservative, by clear zone test. L. monocytogenes, S. aureus and A. hydrophila were completely inhibited at 0.4∼1.6% level while E. coli and S. typhimurium were very resistant to the pine needle extracts. Green tea extracts completely inhibited all strains tested at 0.2∼1.0% level and bactercidal to all strains except L. monocytogenes at 0.5∼2.0% level. Antibacterial activities of pine needle and green tea extracts were stronger than that of sodium benzoate. The order of antibacterial activities of pine needle and green tea extracts to the pathogenic bacteria was GTE > GTW > PNE > PNW. This result suggests that green tea extracts can be used as an effective natural antibacterial agent in food.

• Journal of Nutrition and Health
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• v.12 no.3
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• pp.33-39
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• 1979

The antithiamin activity(ATA) and tannin content were determined for 10 kinds of herbal teas popular in Korea, also on the urinary thiamin excretion and growth rate of rats provided with certain of these teas replacing water. The results are summarized as follows: 1) The tea bag and IT-A had higher ATA (mg thiamin destroyed/g tea), while GT-A and Omiza-tea had lower activity. Different brands of the teas refulted in extremelw different ATA ana tannin content. 2) The body meight gain in the feeding groups of GT-B and GE-B were a little lower than that of the feeding groups of water, LT and IT-A, but these differences were not significant. 3) The food consumption, the food efficiency and the drink consumption of all groups for the total feeding term were not significant. 4) The thiamin excretion was higher in the LT, GT-B groups but lower in the If-A group -when compared to the water group, none of these results were significant.

• Food Science and Preservation
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• v.8 no.2
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• pp.206-212
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• 2001

Water extract of green tea(GTW) and 70% ethanol extract of green tea(GTE) were prepared for the test of antibacterial activity. The sensitivity of Staphylococcus aureus and Salmonella typhimurium to the green tea extracts in various pH of culture broth was tested. Tryptic soy broth(TSB) containing 0∼2%(w/v) of green tea extracts was adjusted to pH 5.0∼7.0 and inoculated with 10$\^$5/∼10$\^$6/ cells/ml of each bacteria. The plate counting method and clear zone test were used to determine inhibitory effect of green tea extracts. Green tea extracts completely inhibited the growth of S. aureus at 0.5% level and bactercidal at 0.5∼1.0% level of GTW and GTE at pH 5.0∼7.0. Green tea extracts were bactercidal to S. typhimurium at 1.5∼2.0% level of GTW and 1.0∼2.0% level of GTE at pH 7.0. Sal. typhimurium was more resistant than S. aureus. in same concentration of green tea extracts at same pH. The resistance of S. aureus and Sal. typhimurium was increased with decreasing pH of culture broth. The morphology of S. aureus cells treated with green tea extracts showed damage of cell wall and cytoplasmic membrane. Severely damaged cells of S. aureus lost electron dense material and cytoplasm. Green tea extracts stimulated autolysis and cell death of S. aureus. This result suggests that green tea extracts can be used as an effective natural antibacterial agent in food.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.1063-1067
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• 2004

To elucidate the effect of protein films containing an antioxidant on lipid oxidation of fish paste products during storage, zein and soy protein isolate (SPI) films containing green tea extract were prepared and their physical properties were examined. Tensile strength and elongation of the protein films decreased by the addition of green tea extract compared to the control. Due to the addition of green tea extract, SPI film had an increase in yellowness, but zein film had a decreased yellowness. Wrapping of fried fish paste products by the zein and SPI films containing the antioxidant retarded lipid oxidation at 2 day storage by 3.6 mg MDA/kg sample and 3.6 mg MDA/kg sample, respectively, for instant fish paste compared to the control. For processed fish paste, they decreased the degree of lipid oxidation by 1.6 mg MDA/kg sample and 0.6 mg MDA/kg sample, respectively.

• Journal of the Korean Applied Science and Technology
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• v.22 no.3
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• pp.241-249
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• 2005

This experiment extracted the natural green-tea using ethanol and obtained the refined oil component after filterated green-tea extract. This study tested the antimicrobial effect as characteristics experiment, and analyzed refined oil component with pH-meter and GC/MS. In the result of this experiment, it obtained the next conclusions. In the first result of extraction experiment, it could know that extraction ratio of refined oil component appeared about 9.0%. In the second result of characteristics experiment, it could certificate that in case of increasing the refined oil component in concentration of 100ppm and above, and according to passage of cultivation time, the number of S-aureus and E-coli in microbe decreased less and less. But in case of blank test not adding the refined oil component, the number of microbe increased more and more. In these phenomena, it could certificate that refined oil component of green-tea appeared antimicrobial effect against microbe. In the third result of instrumental analysis, refined oil component of green-tea appeared about 7.6 in 1% distilled water solution with pH-meter, and the aromatic components of benzene, bonyl acetate, campene, ${\alpha},{\beta},{\gamma}$-pinnene etcs from refined oil component of green-tea was detected with GC/MS.

• Journal of the Korean Applied Science and Technology
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• v.36 no.1
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• pp.23-33
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• 2019

After making tea by steaming the Burdock(Arctium lappa) nine times and drying it nine times, the ingredients and functions of the Burdock tea were compared to those of M company. The tea's calories were 346.48kcal/100g, carbohydrates were 72.75g/100g, crude protein was 11.98g/100g, and crude ash was 5.01g/100g. The total of free sugars were 31.93mg/100, among them, fructose was 26.27, sucrose was 1.27 mg/100g. The inorganic material contents were 1,476.21mg/100g of potassium, 255.96 mg/100g of calcium and 311.41 mg/100g of magnesium. The saturated fatty acids were 40.73mg/100g and the unsaturated fatty acids were 59.27mg/100g, among which the linoleic acid was 41.28mg/100g, the palmitic acid was 33.11mg/100g, the oleic acid was 10.07mg/100g and linolenic acid was 7.92mg/100g. DPPH radical scavenging was 33.9% of teas that were developed, 2.3% of M's tea for comparison, and 37.2% of indiex material. ABTS radical scavenging were 90.7% of teas developed, 85.9% of M's tea and 37.2% of index materials, and SOD like activities were 11.3% of teas developed and 50.5% of M's teas. The flavonoid content was 2.6 fold of the tea developed, 2.9 fold of M's tea and 1.7 fold of index material. The polyphenol content was 33.8 fold of teas developed, 38.9 fold of the M's tea and 13.8 fold of the index material. The sensory evaluation compare to the one-time extract and the five-time extract. Based on the one-time extract, the color were 65.9 % of the five-time extract tea were developed, 12.8 % of the M's tea. Flavour were 78.0% of the tea developed and 33.3% of the M's tea, tastes were 71.4% of the tea developed, 20.7% of the M's tea. The cart for comparison showed that while the extract decreased as we developed it, the overall symbolism decreased to 21.4% after five time extracts, the developed tea decreased to 72.1%. We believe that the developed tea will have a greater effect on preventing and improving diseases as it has a stronger antioxidant function, more effective substances, and a higher level of symbolism than the comparative M squared tea and surface substance.

• Journal of Ginseng Research
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• v.1 no.1
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• pp.79-88
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• 1976

A determinatien of the saponins in ginseng tea and extract was carried out by using the quantitative TLC autodetector equipped with a hydrogen flame ionization detector. In order to apply to the Quality central of the ginseng tea and extract. the optimum condition and recovery percentage for the quantitative determination of saponins in these products duo studied. The results obtained were as follows: The method was adequate to estimate whether the ginseng extract used for the Products and She raw ginseng extract were the same quality or net. Most of the individual peak area was increased with the concentration of the total saponin. But some of the peak areas were net increased quantitatively in the ease of the sample containing high concentration ginseng extract. To deternine the saponins in ginseng tea correctly high volume low concentration was better than the low volume high concentration. Optimum concentration of ginseng extract in sample to determine the individual saponins was in the range of 0.5∼1.5g. The recovery percentage of the total saponin was 99.5% on the average.