• 한국식품영양학회지
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• 제30권6호
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• pp.1149-1156
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• 2017

We investigated the quality characteristics and the antioxidant efficacy of roasted maize tea according to different moisture contents (9% to 14%) using the puffing system (PS) and the roasting system (RS). Compared with the RS, the PS caused higher turbidity (0.017 vs. 0.003 in PS-14% vs. RS-14%), brown color intensity (0.170 vs. 0.059 in PS-14% vs. RS-14%), a-values (0.20 vs. -0.44 in PS-14% vs. RS-14%), b-values (7.90 vs. 5.57 in PS-14% vs. RS-14%), and a lower L-value (19.67 vs. 21.03 in PS-14% vs. RS-14%). Total polyphenol and flavonoid contents of roasted maize tea were increased along with the moisture content and they were higher with the PS (polyphenol; 5.95 mg GAE/g, flavonoids; 1.27 CE/g in PS-14%) than with the RS (polyphenol; 5.39 mg GAE/g, flavonoids; 1.12 mg CE/g in RS-14%). The DPPH and ABTS radical scavenging effects of roasted maize tea were also increased along with the moisture content, and the scavenging efficacy was significantly higher with the PS (DPPH; 160 mg TE/100g, ABTS; 507 mg TE/100g in PS-14%) compared with the RS (DPPH; 120 mg TE/100g, ABTS; 362 mg TE/100g in RS-14%). The polyphenol levels were significantly correlated with turbidity, brown color intensity, and L, a, and b-values of the roasted maize tea. In addition, an increase of the total polyphenol content in roasted maize tea induced antioxidant activities. As a result, an increase in polyphenols during the roasting process induced antioxidant activities which could prevent damage from free radicals.

• 대한방사선협회지
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• 제28권1호
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• pp.39-48
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• 2002

The Green tea, one of the most popular and favorite drinks in eastern societies, has been reported to have various therapeutic properties. These includes anti-cancer, anti-oxident, anti-endocrine disrupter effects. Its anti-cancer effect was said to be ac

• 한국식품영양과학회지
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• 제39권8호
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• pp.1201-1206
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• 2010

갈색 유색미의 생산증대와 소비증진을 위한 방편으로 GABA 함량이 높은 갈색 유색미차를 개발하기 위한 기초연구를 행하였다. 이를 위해 볶음온도와 시간을 달리하여 갈색 유색미를 볶은 후 색도와 GABA 함량을 측정하였고, 이들의 분쇄물을 열수로 침출한 후 갈색도, 탁도, 환원당, 가용성 고형분, 총 polyphenol, pH와 같은 이화학적 특성을 측정하였다. 또한 $170^{\circ}C$에서 10, 20, 30분간 볶은 갈색 유색미의 차의 관능적 특성을 알아보았다. 볶음온도와 시간이 증가함에 따라 갈색 유색미의 L값, a값, b값의 색도는 모두 감소하였고, GABA 함량도 낮아졌다. $170^{\circ}C$에서 10분간 볶은 경우의 GABA 함량이 6.83 mg/100 g으로 가장 높았고, $220^{\circ}C$에서 11분간 볶은 경우가 가장 함량이 낮았다. 갈색유색미 차의 갈색도, 탁도, 환원당, 가용성 고형분, 총 polyphenol 함량은 갈색 유색미의 볶음온도와 시간이 증가함에 따라 증가하였으며, pH는 이와는 반대로 감소하였다. 30분간 볶아 만든 갈색 유색미 차의 색, 향, 맛, 종합적 기호도가 가장 높았는데, 이는 다른 차보다 색, 향, 맛이 가장 강하였기 때문이었다. 이에 GABA 함량도 높고 소비자의 기호도를 만족하는 차를 개발하기 위해서는 GABA 함량이 높은 10분간 볶은 갈색 유색미와 30분간 볶은 갈색 유색미를 적절히 혼합하여 제조할 필요가 있을 것으로 생각되었다.

• Journal of Applied Biological Chemistry
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• 제54권1호
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• pp.33-40
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• 2011

Ionizing radiation can be used to improve the color of green tea extract to brighter. As a result, the irradiated green tea extract can be applied easier and broader in food or cosmetic industry. To confirm the retention of the biological activities of the cosmetic products added with green tea polyphenols (PPs), the real cosmetic products including a skin lotion (PS) and an essence (PE) cream were manufactured. Irradiation also applied to the manufactured cosmetic products to see their improvement of color and changes of biological activity. The PP showed 72% of electron donating ability (EDA) at a 5 ppm concentration and the PS and PE containing 2% PP showed higher than 60%, which was similar inhibition activity to vitamin C. The inhibition of superoxide dismutase (SOD)-like activity of PP, PS, and PE were higher than 55% at a 500 ppm concentration and the inhibition of xanthine oxidase (XOase) were also higher than 65% at a 200 ppm concentration. The measurement of lipid oxidation by addition of $Cu^{2+}$ and $Fe^{2+}$ as prooxidants showed that PP and PS had higher metal chelating ability for $Fe^{2+}$ than that of PE and the ability increased by increase of polyphenol concentration isolated from green tea. The $Cu^{2+}$ chelating ability of PP and PS showed higher than 90% at a 200 ppm concentration. Therefore, it is concluded that addition of PP in manufacturing PS and PE retains its biological activities including EDA, inhibition of XOase and SOD-like activity, and metal chelating ability in the manufactured cosmetic products. In addition, irradiation of PS and PE improved color of the products containing PP brighter without any adverse changes in biological activity of the products.

• 생명과학회지
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• 제6권2호
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• pp.104-110
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• 1996

The present study was conducted to elucidate the functional property of tea extract obtained from tea extracts, semi-fermented tea(oolong tea) and fermented tea(black tea). Tea extracts exhibited remarkable nitrite-scavenging actions, and the action increased with the increased of the amount of tea extracts. The nitrite-scavenging actionof tea extracts showed pH dependent, highest at pH 1.2 and lowest at pH6.0. The nitrite-scavenging rate in tea extracts/amine/nitrite systems proved to be faster than that in amine/nitrite systems. To screen the nitrite-scavenging factors, tea extracts were fractionated into water-soluble, methanol-soluble, methanol-precipitate and crude catechin fraction. Among these fractions of tea extracts, the crude catechin fraction possessed greater nitrite-scavenging action than the other fractions. The nitrite-scavenging action of tea extracts increased with the contents of total phenols and an absorbance at 280nm, nitrite-scavenging factors were supposed to be and catechins in tea polyphenol compounds.

• Journal of Applied Biological Chemistry
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• 제55권2호
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• pp.95-101
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• 2012

본 논문에서는 오죽(Phyllostachys nigra Munro)의 잎과 죽순을 사용하여 차 가공공정을 통한 오죽잎차와 오죽죽순차가 제조되었고, 이들에 대한 영양성분 분석을 실시하였다. 뿐만 아니라, 일반적인 차를 음용하는 조건($80^{\circ}C$ 물, 10분)에서 이들 차로부터 얻을 수 있는 수용성 물질의 추출율과 총 폴리페놀 함량, 총 플라보노이드 함량이 가공되지 않은 오죽 원재료 및 마테차, 녹차와 비교되었다. 마지막으로 차 음료에 포함된 항산화능과 각 항산화 화합물을 탐색하고자 온라인, 오프라인 항산화 분석이 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and di(phenyl)-(2,4,6trinitrophenyl)iminoazanium (DPPH) 라디칼에 대해서 이루어졌다. 본 논문의 결과는 오죽으로부터 제조된 이들 차가 다양한 영양성분을 함유하고 있고, 건강에 이로운 전통차로 음용될 수 있음을 보여주었다.

• 대한의생명과학회지
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• 제17권1호
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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.

• 한국유기농업학회지
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• 제29권4호
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• pp.613-623
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• 2021

This study was conducted to investigate the effect of addition levels of coffee and green tea by products extract including polyphenols through hot water extraction on rumen fermentation. The treatment groups consisted of coffee extract (CO), green tea extract (GR) and mixed extract (MIX), and the addition level was 10 µL, 20 µL and 30 µL of three levels. The experiment consisted of a total of 10 experimental groups including the control group, and a full factorial design was used. The effect of polyphenol addition in coffee and green tea by-products was analyzed through main and interaction effect of statistical analysis. The total polyphenol content of the extracts was 106.15, 79.10 and 185.25 ㎍ GAE/g DM for coffee by-product, green tea by-product and mixture, respectively. Total gas production was significantly lower in the treatment groups than in the control (114.00 mL/gDM) (p<0.05). Methane emission tended to decrease as the polyphenol addition level increased. Moreover, the MIX showed the lowest methane emission when 30 µL was added (p<0.05). Volatile fatty acids showed a significant difference compared to the treatment group as a control (98.06 mM) (p<0.05), but there was no change according to the level of polyphenols. As a result of the main effect and interaction, it is thought that the effect on methane reduction and improvement of rumen fermentation in MIX20 can be expected. In a series of studies, the addition of 20 µL of a blended extract of coffee and green tea by-products is thought to reduce methane to levels that do not inhibit rumen fermentation.

• Preventive Nutrition and Food Science
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• 제7권3호
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• pp.327-331
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• 2002

Tea is a pleasant, popular and safe beverage in the world. During the past decade, epidemiological studies have shown that tea catechins intake is associated with lower risk of cardiovascular disease. Tea provides a dietary source of health-promoting components to help humans reduce a wide variety of cancer risks and chronic diseases. The antioxidative activity of tea-derived catchins has been extensively studied. The antioxidant effect is a synergistic action between catechins e.g. EGCG, EGC, ECG, EC, pheophytins a and b, and other components in tea leaves, which aye more bioavailable for human body. Green tea has a Higher content of catechins than other kinds of tea. Green tea extract with hot water has high potential and more efficiency to reduce cancer risk than any other tea products or pure EGCG. Protein, iyon, and other food components may interfere with the bioavailability of ten catechins. Interaction of catechins with drug affects the cancer-preventive activity of some cancer-fighting medication. Further studies are required to determine the bioavailability of tea catechins and cancer-preventive functionality.

• Applied Biological Chemistry
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• 제50권3호
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• pp.210-216
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• 2007

방사선 조사한 녹차 폴리페놀을 스킨과 에센스에 첨가하여 방부제를 첨가하지 않았을 때의 항균효과 및 방부효과를 검증하고 무방부제 화장품으로서의 가능성을 검토하였다. 항균력 측정 결과, C. albicans를 제외한 모든 균주에서 항균효과가 나타났으며, 피부상재균인 S. aureus에서 항균효과가 높게 나타났다. MIC 측정 결과, E. coli와 C. albicans의 경우 2,500 ppm에서, S. aureus의 경우 1,000 ppm에서 저해농도를 나타내었으며, MBC 측정 결과, C. albicans를 제외한 모든 균주에서 측정이 가능하였으며, E. coli의 경우 10,000 ppm, S. aureus의 경우 5,000 ppm에서 모든 균이 사멸하였다. 시간에 따른 생균수 측정 결과, 시간이 지남에 따라 균의 증식을 억제하여 항균력이 뛰어남을 알 수 있었다. 이와 같은 결과로 미루어 보아 녹차폴리페놀은 스킨과 에센스에 첨가 시 항균효과가 우수하여 화장품 첨가제로 이용이 가능할 것으로 사료된다.