• Korean Journal of Soil Science and Fertilizer
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• v.35 no.6
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• pp.381-386
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• 2002

A field experiment was conducted to evaluate the effect of split-application of slow-release fertilizer on the tea plant. The yield of the 1st harvested tea leaves had increased 12% in the slow-release fertilizer(two time split manuring) compared with the traditional manuring(four time split manuring), but that of the slow-release fertilizer to one time split manuring had decreased $6{\pm}3%$. In case of the 1st harvested leave, the contents of chemical components related to quality such as total nitrogen, total amino acid, chlorophyll, vitamin C and theanine were somewhat higher in the leaves of slow-release fertilizer(two time split manuring) treatment than in the traditional manuring, but that of tannin was low. The one time split manuring of slow-release fertilizer had a contrary tendency with two time split manuring treatment. In scoring test, appearance and quality of green tea were more excellent in the two time split manuring compared with one time split manuring of slow-release fertilizer and with the traditional manuring (four time split manuring). Therefore, use of slow-release fertilizer increased yield and quality of tea leaves, and decreased loss of nitrogen, phosphate and potassium.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.9
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• pp.1439-1447
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• 2019

Objective: The aim of this study was to evaluate the effect of dietary incorporation of tanninrich woody species on meat oxidative stability, carcass traits and meat quality in goats. Methods: Two tannin-rich species were tested using a three-treatments feeding trial, where treatments consisted of: Larrea divaricata and Acacia aroma both at 12.5% in dry matter basis of the diet and a control diet (alfalfa hay). All feeding diets were iso-protein and iso-energy. Carcass conformation, carcass compactness, carcass fatness and subcutaneous fat deposition were evaluated. Intake, liveweigh, Longissimus thoracis et lumborum muscles of goats were analyzed in order to evaluate quality parameters such as pH value, instrumental color evaluation, water holding capacity, total phenolic content, antioxidant activity, meat oxidative stability and fatty acid profiles in meat. Results: Feed intake, liveweight gain, carcass, and meat traits did not differ among treatments. Changes in meat lipid profile among treatments were observed for oleic and elaidic acid contents. Meat total phenolic content and antioxidant activity did not differ among treatments; although, meat oxidative status after storage at room temperature, as well as under refrigerated and frozen conditions were different between control and both supplemented groups. Conclusion: The inclusion of Acacia aroma and Larrea divaricata leaves in goat diet enhanced meat oxidative stability. Modulation of the ruminal biohydrogenation of fatty acids produced by condensed tannins of these plant species need to be further investigated.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.5
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• pp.720-726
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• 1995

Chemical components relevant to the characteristic taste of the Korean native persimmon(Diospyros kaki, Thumb) leaf tea were analyzed. Samples were processed by using three different methods ; SHT(steamed and then hot-air dried), DHT(dried in the shade, steamed and then hot-air dried) and RHT(roasted and then hot-air dried). The components analyzed were general compositions of dried perisimmon leaves and extracted solution. The composition of moisture, ash, crude lipid and total nitrogen did not show significant variation among different processing methods of the persimmonleaf tea. The contents of caffeine, tannin and vitamin C in persimmon leaf tea were in the range of $178.4~209.8{\mu}mol/g$, 29.1~38.5mg% and 325.3~2084.7mg%, respectively. The vitamin C content was significantly higher in the RHT than other treatments. The contents of caffeine, tannin and vitamin C in the tea extracted solution were in the range of $101.5~130.1{\mu}mol/g$, 15.4~25.9mg% and 111.0~1274.3mg%, respectively. The vitamine C in the tea solution was the highest in the RHT treatment and 61.1% of vitamin C in the leaf tea was extracted out in these processing methods. The major amino acids contained in the leaf tea were in decreasing order glutamic acid, aspartic acid, leucine and phenylalanine, these four amino acids consisting 38.9~39.8% of the total amino acid contained in the persimmon leaf tea. The major amino acids contained in the tea solution were glutamic acid, proline, histidine and arginine. Six kinds of 5'-nucleotides, CMP, AMP, UMP, IMP, GMP and hypoxanthine were detected and CMP was the most abundant component in fresh leaf, leaf tea and tea solution. The second highest 5'-nucleotides in both leaf tea and tea solutions were GMP, AMP and UMP in all processing method. The highest free sugar contained in the fresh leaf tea and tea solution was sucrose.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.257-261
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• 2003

Chemical components relevant to the characteristic antimicrobial activities of the Korean chestnut (Castanea crenata S. et Z.) leaves and flowers were analyzed. The composition of free sugar were sucrose, maltose in the chestnut flowers and sucrose, glucose, fructose in the chestnut leaves. The contains of tannin were 0.16% in the chestnut flower and 1.98% in the chestnut leaves. In fatty acids case, the linoleic contents were significantly high in the chestnut leaves and flowers. The organic acids showed high composition to succnic and citric acid in the chestnut leaves. The ammo acid compositions showed high contents to aspatic acid, proline, glutamic acid, glycine and methionine in the chestnut leaves and flowers. The total amino acid showed significantly higher in the chestnut leaves than flowers. The major minerals contained in the chestnut leaves and flowers were K, Ca, Ng, Fe, Mn and Al. Ascorbic acids were detected highly in the chestnut leaves and flowers.

• Korean journal of food and cookery science
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• v.21 no.5
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• pp.709-716
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• 2005

The aim of this study was to determine the optimal cooking conditions for astringent persimmon concentrates. With increasing time of concentration, the moisture contents and L-, a- and b-values all decreased, whereas the brix level and viscosity increased. The crude protein, fiber and ash increased and the vitamin C decreased by concentrating. The pH was the lowest at 23 hrs of boiling concentration. With longer boiling concentration time, the fructose, glucose, and sucrose levels increased but the maltose level decreased. The DPPH radical scavenging effects of astringent persimmon concentrates were more than 92%. The total phenolics, flavanol tannin, leucoanthocyanin, and chlorogenic acid levels increased with longer boiling concentration time. In the sensory evaluation of the astringent persimmon concentrates, overall acceptability was the best at the 23-hr boiling concentration. From the above results, the 23-hr boiling, astringent persimmon concentrates could be useful for cooking in terms of obtaining the high amounts of phenolic compounds as functional compounds and overall acceptability.

• Applied Biological Chemistry
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• v.39 no.4
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• pp.327-331
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• 1996

This experiment was conducted to establish the efficient extraction condition for anthocyanin and tannin pigments contained in rice bran of colored rices. Efficiency of the pigment extraction was maximum when the concentration of mired solvent of methanol(3) : ethanol(7) was 70%. In purple rite(anthocyanin pigment), ‘Kilimheugmi’, 80% ethanol containing 0.5% malic acid showed the highest extraction efficiency and stability with a maximum absorbance wavelength$(\lambda_{max})$ at 538 nm. In red rice(tannin pigment), ‘Jagwangdo’, 80% ethanol containing 0.01% citric acid showed the highest extraction efficiency and stability with a maximum absorbance wavelength$(\lambda_{max})$ at 456 nm. The relative optical density of the pigments increased until the solvent temperature was reached at $70^{\circ}C$, but drastically decreased over at $90^{\circ}C$ due to color change. The higher amount of the pigment was ertracted from the longer shaking time of the solvent. Ten minutes was enough for the grinding time of rite bran in solvent. Supernatant of the pigment extractives after one day storage at $4^{\circ}C$ in dark chamber revealed higher optical density than the filtration of the pigment extractives.

• Food Science and Biotechnology
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• v.15 no.5
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• pp.728-734
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• 2006

The tannins represent a highly heterogeneous group of water-soluble plant polyphenols that may play an important role in antimutagenic and antioxidant properties. We investigated the antioxidant function of tannic acid in comparison to other phenolic compounds including catechin, chlorogenic acid, cinnamic acid, ellagic acid, and gallic acid for their ability to scavenge several stable radicals and reactive oxygen species (ROS) such as ${\bullet}DPPH^+$, ${\bullet}ABTS^+$, hydrogen peroxide, hydroxyl radical, and superoxide radical. The ability of tannic acid to decrease paraquat-induced lipid oxidation in mouse liver and lung through its antioxidant properties was also assessed. The results showed that almost all the tested compounds have stable radical scavenging activity except cinnamic acid. Tannic acid, gallic acid, and ellagic acid demonstrated remarkable ROS scavenging properties toward $H_2O_2$, ${\bullet}OH^-$, ${\bullet}O_2^-$ and especially only tannic acid could inhibit paraquat-induced lipid peroxidation effectively in mouse liver and lung. Based on these results, it appears that increased number of galloyl and ortho-hydroxyl groups enhances the antioxidant activity of phenolic compounds and tannic acid is evaluated as the most effective antioxidant among all the tested compounds. These results suggest that the tannins, especially tannic acid, can be used as therapeutic agent for various diseases caused by ROS.

• Journal of the East Asian Society of Dietary Life
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• v.12 no.1
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• pp.32-37
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• 2002

In order to promote the utilization of persimmon leaf as food, chemical components in freeze dried Persimmon leaves were analyzed. The proximate composition was composed of moisture(79.65%), crude protein(17.97%), crude fat(1.33%), ash(2.37%), crude fiber(2.01%). During growth, moisture content was decreased and crude fat, crude fiber and ash were increased, respectively. Free sugar was composed of glucose, fructose, sucrose, raffinose. Nonvolatile organic acid contents were composed of oxalic acid, levulenic acid, magic acid and citric acid in the order. 18 amino acids of total amino acid in persimmon leaves were detected and major amino acid were glutamic acid, aspartic acid, leucine, phenylalanine, arginine and valine. The soluble tannin and vitamin C of persimmon leaves were 6859.37 mg% and 1487.12 mg%. During growth, its contents increased and then decreased after 20th June.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.4
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• pp.478-482
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• 2000

Whole cassava (Manihot esculenta, Crantz) crop was harvested about 10-15 cm above ground at 3 months after planting and sun dried for 1-3 days or until the leaves were crispy-dried and the branches and stems were mostly wilted to produce cassava hay. Cassava hay (CH) contained 86.3% DM, 8.9% ash, 23.6% CP, 44.3% NDF, 30.0% ADF, 5.8% ADL, 0.257% condensed tannin and 0.35 mg % HCN, respectively. In addition, CH contained relatively higher amino acid than alfalfa hay especially methionine, isoleucine, leucine and lysine. Ruminal fermentation of CH resulted in high concentrations of $C_2$, $C_3$, and $C_4$ at 72, 17 and 7 mol/100 mole, respectively. A feeding trial was conducted to study on effect of feeding of cassava hay in late lactating dairy cows fed on urea-treated rice straw during the dry season on their intake, ruminal pH, $NH_3$-N, milk yield and compositions. Thirty, Holstein-Friesian crossbred cows in their first lactation were randomly assigned in a randomized complete block design to receive five different dietary treatments: T1=supplementation of concentrate to milk yield at 1:2, T2=supplementation of concentrate to milk yield at 1:2+0.56 kg DM, T3=supplementation of concentrate to milk yield at 1:3+1.3 kg DM CH, T4=supplementation of concentrate to milk yield at 1:4+1.70 kg DM CH, T5=CH fed on ad libitum+small concentrate supplement. All cows received urea-treated rice straw as a roughage source throughout a 80 d feeding trial. The experiment revealed that cassava hay contained high level of protein and minimal level of tannin at 3 months of harvest. Tannin intake ranged from 1.44 to 13.36 g/hd/d and did not affect on urea-treated rice straw intake. Milk yield across treatments were similar (5.4-6.3 kg/hd/d) (p>0.05) but 3.5% FCM was highest in cows received CH at 1.70 kg/hd/d. Feeding of cassava hay resulted in increasing milk fat (4.0 to 4.6%) (p<0.05) and milk protein (3.8 to 5.3%) (p<0.05). Moreover, the use of CH could reduce concentrate supplementation to milk yield from 1:2 to 1:4, respectively, thus resulted in more milk income return.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.2
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• pp.99-104
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• 1983

Chemical changes of major tea constituents by tea manufacture were examined by the quantitative masurements of tannin, caffeine, free sugars and total amino acid. The sample used in this experiments was fresh green and black tea leaves, green tea prepared by classical panning process and black tea prepared by commercial process. The results obtained are as follows: Compared with fresh tea leaves, tannin was increased 2% in green tea and decreased 56.5% in black tea by tea manufacture. Caffeine was increased 25.9% in green tea and decreased 3.1% in black tea. Total free sugars were decreased 78.2% and 76.7% in green tea and black tea, respectively. Total amino acids were decreased 26.1% and 18.8% in green tea and black tea, respectively.