• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.1
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• pp.154-159
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• 1995

Inhibition of xanthine oxidase by tea extracts obtained from non-fermented tea(steamed green tea and roasted green tea), semi-fermented tea(oolong tea) and fermented tea(black tea) were investigated. The crude catechin fraciton had a hgher inhibitory effect against xanthine oxidase, and the effect was increased with the addition of tea extracts. Their inhibitory effect were hardly influenced until extracted three times with hot water. According to the investigation of catechins in the crude catechin fraction obtained from tea extracts, (-)-epicatechin-(EC), (-)-epicatechin gallate(ECg). (-)-epigallocatechin(EGC) and (-)-epigallocatechin gallate(EGCg) were 80.1$\mu\textrm{g}$/mg 113.5$\mu\textrm{g}$ /mg, 186.3$\mu\textrm{g}$/mg and 367.7$\mu\textrm{g}$/mg in steamed green tea, and 75.6$\mu\textrm{g}$/mg, 114.7$\mu\textrm{g}$/mg, 193.7 $\mu\textrm{g}$/mg and 381.9$\mu\textrm{g}$/mg in roasted green tea, and 69.4$\mu\textrm{g}$/mg, 110.0$\mu\textrm{g}$/mg, 127.1$\mu\textrm{g}$.mg and 464.9$\mu\textrm{g}$/mg in oolong tea, and 78.1$\mu\textrm{g}$/mg, 171.8$\mu\textrm{g}$/mg, 80.7$\mu\textrm{g}$/mg and 51.4$\mu\textrm{g}$/mg in black tea, respectively. Order of the content of these catechins was (-)-EGCg>(-)-EGC>(-)-ECg>(-)-EC in steamed green tea, roasted green tea and oolong tea, and was (-)-ECg>(-)-EGC>(-)-EC>(-)-EGCg in black tea. Also the concentration of catechins was hardly influeced until extracted three times. The inhibition ratio of xanthine oxidase by autherntic catechins was hardly influenced until extracted three times. The inhibition ratio of xanthine oxidase by authentic catechins was 94.9% and 87.6% by addition of 5.0$\mu\textrm{g}$/ml of (-)-EGCg and (-)-ECg, respectively. the inhibitors of xanthine oxidase were supposed to be due to (-)-ECg and (-)-EGCg in tea polyphenol compounds.

• Preventive Nutrition and Food Science
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• v.2 no.2
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• pp.138-143
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• 1997

Crude catechin extracts were prepared using ethyl acetate from Korean Puerariae Radix (PR) and their biological effects on the alcoholic liver damage were investigated in male Sprague-Dawley rats (6 weeks old). Ethanol (5g ethanol/kg body weight/day) administration was performed for 8 weeks and after ethanol consuming rats were treated with one or two% catechin extracts of diet for 8 weeks. At the end of experimental period, lipid hydroperoxides in liver were analyzed using a chemiluminescence-high performance liquid chromatography (CL-HPLC) method. Compared with control animals, ethanol consumed rats showed lighter body weights, lower ratios of liver/body weight, higher activities of GOT and GPT, and increased lipid hydroperoxide amount in liver. With one or two% catechin extracts treatment, GOT and GPT activities returned to normal ranges. Lipid hydroperoxide contents in liver of on or two% PR treated rats lowered to 20% or 25% respectively, compared with the levels of those ethanol consumed animals without catechin extracts treatment. Therefore, we concluded that on or two% PR crude catechins treatment could be effective for alcoholic liver damage caused by lipid peroxidation.

• YAKHAK HOEJI
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• v.36 no.3
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• pp.205-211
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• 1992

A simple dignostic method using Fast Atom Bombardment mass spectrometry was applied to the characterization of green tea flavonols from the eluates of Sepahadex LH-20 column chromatography. From the ethyl acetate extracts, crude mixture of flavonol fraction(Fr.$1{\sim}4$) were separated by the stepwise gradient elution with 30, 45, and 60% aqueous acetone. Procyanidine B analogues were found to be typical constituents of Fr. 1. Main components of Fr. 2 were catechins and gallo-catechins. Fr. 3 contained mainly ester type compounds, catechin-gallates, gallocatechin-gallates with their analogues. Fr. 4 was contaminated with some phthalate esters.

• Journal of Life Science
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• v.6 no.2
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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.

• Food Science and Preservation
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• v.15 no.4
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• pp.576-581
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• 2008

The chemical components of the wild vegetables Solidago virgaurea spp. gigantea, Aster glehni var. hondoensis, and Aruncus dioicus var. kamtschaticus grown on Ulleung island, Korea were investigated. In dried powders of these three wild vegetables, the contents of moisture, crude protein, crude lipid, crude fiber, and crude ash were 3.77-5.72%, 15-29%, 3.50-6.68%, 4.00-6.01%, and 8.70-10.54%, respectively. There were differences in the levels and nature of organic acids in the vegetables; the major organic acids were succinic acid, citric acid, and malonic acid. The major free amino acids in the vegetables were glutamic acid, aspartic acid, arginine, and phenylalanine. Riboflavin contents were 90 mg% in Aruncus dioicus var. kamtschaticus and $2{\sim}3$ mg% in the other vegetables. The thiamin contents were 113 mg% in Aster glehni var. hondoensis, 85 mg% in Aruncus dioicus var. kamtschaticus, and 71 mg% in Solidago virgaurea spp. gigantea. The major fatty acids in the three vegetables were linolenic acid, linoleic acid, and palmitic acid; 60% of total fatty acid was linolenic acid. Catechins were present at 5.37 mg% in Aruncus dioicus var. kamtschaticus, 2.46 mg% in Solidago virgaurea spp. gigantea, 1.29 mg% in Aster glehni var. hondoensis.(-) ECC was detected in only Aruncus dioicus var. kamtschaticus. The contents of Ca, P, and Na in the three vegetables were higher than the contents of other minerals.

• Journal of Food Hygiene and Safety
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• v.13 no.4
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• pp.377-382
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• 1998

This study was carried out to measure the contents of moisture, crude ash, crude fat, total amino acid, with amino acid composition, vitamin C, ${\beta}-carotene$, vitamin E, total catechins, EGCG, EGC, ECG, EC, GA, caffeine, theobromine and theophylline of the green tea I, II, III, oolong, and black tea. The content of crude fat of green tea I, II, III, oolong, and black teas was 1.1, 2.5, 4.9, 0.8 and 1.2% respectively, total amino acid content was 0.87, 0.78, 0.60, 0.63 and 1.05% respectively, and theanine content was 0.52, 0.48, 0.31, 0.41 and 0.61%, respectively. Total amino acid content of green tea increased in the order of green tea I> green tea II> green tea III, and among the teas, the content of theanine was the highest in the amino acids present. The content of vitamin C of green teal, II, III, oolong, and black tea was 101.6, 87.5, 95.9, 99.1 and 108.0 mg%, respectively, ${\beta}-carotene$ content was 270, 268, 481, 80 and 181 ppm, respectively. Among the ${\alpha}-,\;{\beta}-,\;{\gamma}-\;and\;{\delta}-tocopherol$, the content of ${\alpha}-tocopherol$ was the highest in vitamin E present, and ${\beta}-\;and\;{\delta}-tocopherol$ were not detected in the samples of green teal, II, III, oolong, and black teas. The total catechins of green teal, II, III, oolong, and black teas was 10.5, 10.4, 7.2, 8.4 and 1.8% respectively, and among them, EGCG content was the highest. The content of EGC increased in the order of green tea I > green tea III > green tea II > oolong tea> black tea. The contents EGCG and ECG increased in the order of oolong tea> green tea I > green tea II> green tea III> black tea, and the highest contents of EGCG and ECG were observed in the samples of oolong tea. The content of GA was 0.01, 0.02, 0.05, 0.13 and 0.31%, respectively, and the highest contents of GA, caffeine and theobromine were observed in the sample of black tea. The highest content of theophylline, however, was observed in the sample of green tea I.

• Food Science of Animal Resources
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• v.23 no.2
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• pp.180-185
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• 2003

Rats(Sprague-Dawley) were randomly assigned to the following four groups, control, exercise only, exercise and the intake of DNA, exercise, and the intake of DNA plus crude catechin. 0.4% of DNA from salmon egg and 0.1% crude catechins from Puerariae thunbergiana roots were fed to the rats. The exercise group was exercised in a treadmill at 20 m/min speed for 6 wks. Body weight and body fat weight of 4 groups were investigated, and the body fat composition and antioxidant activity were evaluated by measuring the weight of organs and biochemical test. After 6 wks, body weight did not show any significant differences among those 4 groups, but body fat weight in exercised groups was significantly decreased. The weight of liver, epididymal adipose tissue(E.A.T) and perirenal adipose tissue(P.A.T) were significantly decreased in groups of exercise only, exercise and the intake of DNA, exercise and the intake of DNA plus crude catechin(p<0.05). Phospholipid, cholesterol and triglyceride levels of serum were decreased by exercise, but HDL-cholesterol level of serum was significantly increased(p<0.05). GOT, GPT and glucose levels in serum were slightly decreased by crude catechin, but serum NEFA levels were significantly increased by crude catechin(p<0.05). Results indicated that excercise with the intake of crude catechin would be helpful for the functional development of the compositions in blood lipid.

• Food Science of Animal Resources
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• v.18 no.4
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• pp.348-357
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• 1998

This study was conducted to investigate the effects of mugwort extracts on the blood ethanol concentration and liver function in rats. Sprague-Dawley rats were used, the rats administered with 25% ethanol (5g/kg$.$B.W.) were devided into three groups (CON-E ; 25% ethanol administered to the CON-E) according to the administered ethanol concentration and the levels of administered mugwonts. Mugwont roots extracts were administered via the caudal vein. Ethanol concentration was measured at the time of 0, 1, 2 and 3hr by gas chromatography. GOT(Glutamic Oxaloacetic Transaminase) and GPT(Glutamic Pyruvic Transaminase) were measured at the time of 0 and 5hr. Components of each extracts were analyzed by using high performance liquid chromatography. Cell number, GOT and GPT were investigated by using rat hepatocyte culture. Megwort extracts were added at the levels of 1% or 2%. Hepatocyte culture were into five groups according to the addition levels. The results were summarized as follows ; 1. Catechin contents of 8∼10mg/100g and the contents of (-)-epigallocatechin was high in the water extracts. 2. Ethanol degradation efficiency declines in the following order : MDW-E＞MOH-E＞CON-E. 3. The numbers of rat hepatocytes declines in the following order : 2% MDW-L＞1%MDW-L＞1%MOH-L＞CON-L＞2%MOH-L. These results suggest that crude catechin of mugwort extracts may play important roles to degrade ethanol and recover liver function in rats.

• Korean journal of food and cookery science
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• v.15 no.3
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• pp.224-230
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• 1999

The purpose of this study was to find out the optimal mixing ratio of green tea powder, sugar, and water for the preparation of Seolgiddeok through Response Surface Methodology based on the color, sensory, and texture test. The oganoleptic and textural properties of Seolgiddeok prepared with various concentrations of green tea powder (0% (control group), 0.5% (GT-0.5 group), 1% (GT-1.0 group), 1.5% (GT-1.5 group), 2% (GT-2.0 group)), and their quality changes during storage were also investigated. The optimal mixing ratio of green tea powder, sugar, and water for preparing the best quality Seolgiddeok was 1.0%, 12%, and 22%, respectively. The proximate composition of green tea powder was 21.70% of crude protein, 8.49% of crude lipid, 2.95% of reducing sugar, and 6.40% of ash. The contents of crude lipid, reducing sugar, and catechins in Seolgiddeok added with a green tea powder were increased with increasing the content of green tea powder. The hardness and gumminess of GT-1.0 group were the lowest among four groups, whereas GT-1.0 and GT-2.0 groups had the lowest cohesiveness. While the control group was the lowest in adhesiveness, the springness was not significantly different among all groups. GT-0.5 and GT-1.5 groups were the highest in sweet taste and colorfulness, respectively. However, GT-1.0 group had the best overall quality. Total microbial numbers, the acidity and pH in Seolgiddeok during storage were decreased with increasing green tea powder content, and especially those of GT-1.0 and GT-1.5 groups were relatively the lower than others. The “L” value (lightness) of the control group (no additives) was the highest among five groups, and the value was decreased with storage period, and especially GT-0.5 groups had the lowest brightness. The“a”value (reddness) of the control group was the highest, followed by GT-0.5, GT-1.0, GT-1.5, and GT- 2.0 group in order. The“b”value (yellowness) was increased with the increase of green tea powder content. Above results indicated that GT-1.0 group showed the best quality of Seolgiddeok through organoleptic and rheology tests.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.2
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• pp.190-194
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• 2008

Physicochemical properties of the green tea component enriched mushroom (Flammulina velutipes) were investigated. The yield of mushroom was highest with green tea powder untreated sample and the yield was decreased by the addition of green tea powder. However, hardness was increased by the addition of green tea powder. Analysis of catechins and caffeine in mushrooms showed that catechins were not transferred into mushrooms, whereas caffeine content was increased. The content of total polyphenol in mushroom was not affected by the addition of green tea powder and crude catechins. Analyses of aroma patterns using the electronic nose based on GC with SAW sensor showed that new peaks occurred from 3 to 6 sec in green tea added mushroom. This study showed that functional components and quality of mushroom were possibly improved by incorporating green tea powder in growth medium.