• Korean Journal of Plant Tissue Culture
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• v.27 no.1
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• pp.51-55
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• 2000

To investigate the effect of media and growth regulators in micropropagation of persimmon (Diospyros kaki Thunb.), dormant axillary buds taken from trees of persimmon cultivars such as Ichikikeijiro, Tonawase and Hiratenenashi were used. Shoot tips were successfully cultured in full or half of nitrogen strength of MS medium. The most effective cytokinins for shoot proliferation and elongation of persimmon cv. Ichikikeijiro were 5 mg/L and 2 mg/L zeatin, respectively. Shoots were successfully rooted in 1/2N-MS medium with 1 mg/L IBA.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.4
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• pp.276-280
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• 2013

D. kaki and D. lotus are used as rootstocks for astringent persimmons in Korea but characteristics of their seedlings have not been determined. In this experiment, their seeds were sown in 3-L pots on April 18 and the seedlings were grown until October 24. Growth and nutrient absorption were compared at the end of the season after destructively harvesting the seedlings. Seedling growth of D. lotus was much faster than that of D. kaki in terms of total stem length, stem diameter, and number of leaves. However, chlorophyll value and specific leaf weight were higher in D. kaki than in D. lotus. Dry weight of D. lotus was 3.6- and 3.7-fold higher than that of D. kaki in above-ground parts and the root, respectively. D. kaki seedlings were characterized by higher concentrations of N, P, K, Ca, and Mg in the leaves, stem, or the root. However, total contents of the elements were 1.8- to 3.7-fold higher in a D. lotus seedling due to its greater dry weight. Since D. lotus seedlings absorbed more inorganic elements on a tree basis and grew more vigorously than D. kaki seedlings, the level of fertilization for astringent persimmons should be adjusted depending on rootstocks to maintain the trees at the optimum vigor.

• Preventive Nutrition and Food Science
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• v.16 no.4
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• pp.328-332
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• 2011

After preparation of acetone, ethanol, methanol, and water extracts (10 g/300 mL) of dried persimmon (Diospyros kaki cv. Fuyu) flower-buds, total phenolic contents (TPC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (RSA), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) RSA, reducing power (RP), and tyrosinase inhibitory activity of the extracts were evaluated. The methanol extracts produced the highest TPC (113.39 mg gallic acid equivalents/g), DPPH RSA ($IC_{50}=40.25\;{\mu}g/mL$), ABTS RSA ($IC_{50}=58.17\;{\mu}g/mL$) and RP ($IC_{50}=69.43\;{\mu}g/mL$) activities while the water extracts generated the lowest values. The ethanol extract showed the highest tyrosinase inhibitor activity (88.90%) at a concentration of 1 mg/mL. These results indicated that persimmon flower-buds may be a useful source of natural antioxidants.

• Food Science and Preservation
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• v.4 no.1
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• pp.45-51
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• 1997

In our studies on the role of $\beta$-galactosidase in fruit softening, significant difficulty, was encountered in our attempts to extract RNA from persimmon(Diospyros kaki L. cv. Fuyu) fruit due to astringency and tannin content. Initial, unsuccessful RNA extractions involved methods using guanidinium isothiocyanate/CsCl with and without polyvinylpyrrolidone(PVP), phenol/sodium lauryl sulfate(SDS), guanidinium hydrochloride, as well as polysomal RNA purification method that used 0.2 M Tris-HCI (pH 9.0) containing KCI, Mg-acetate, EDTA, $\beta$-mercaptoethanol, and sucrose. A method was devised which employed treatment of fruit with CO2 gas to diminish astringency prior to RNA extraction, followed by extraction of tissue powders with Proteinase K extraction buffer containing PVP and ascorbate at an alkaline pH. This procedure resulted in the removal of tannins and other polyphenolics and extraction of relatively large amount of high-quality RNA suitable for cDNA library construction and polymerase chain reaction(PCR). Futhermore, the procedure does not use the toxic and corrosive chemical guanidinium isothiocyanate or require ultracentrifugation.

• Proceedings of the Korean Society of Life Science Conference
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• 2000.09a
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• pp.97-97
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• 2000

• Archives of Pharmacal Research
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• v.28 no.6
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• pp.667-674
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• 2005

The leaves of Persimmon (Diospyros kaki L.) has long been used for tea in Korea since it was thought to be effective against hypertension. An anticoagulant fraction was purified through gel filtration G-100, hydrophobic, gel filtration G-150, and FPLC, Phenyl superpose column chromatographies. The purified fraction was homogenous and its Mr was estimated 10,000 Da by gel filtration and SDS-PAGE. The purified fraction was sensitive to treatment of subtilisin B, but not to heat and its activity was not changed after periodate oxidation, indicating that the activity was not due to carbohydrates. It delayed thrombin time (TT), activated partial thromboplastin time (APTT), and prothrombin time (PT) using human plasma. TT was more sensitive than APTT and PT, suggesting that the anticoagulant activity may be caused by a degradation or a defect of fibrin or thrombin. It did not cause the hydrolysis of fibrin after incubation. However, it inhibited thrombin-catalyzed fibrin formation with a competitive inhibition pattern. These results indicate that it may be an antithrombotic agent and that it is bound to fibrinogen binding sites of thrombin.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1035-1038
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• 2009

Phytochemical investigation of the methanolic extract of Diospyros kaki leaves led to the isolation of osmanthuside H (1) and a new phenol glycoside, named gamnamoside [4-(3-hydroxypropyl)-2-methoxyphenol $\beta$-D-apiofuranosyl( 1 $\rightarrow$ 6)$\beta$-D-glucopyranoside] (2) along with (-) catechin (3) through a series of reversed phase column chromatography and preparative C18 HPLC. The structures of the isolates were determined by spectroscopic methods including IR, UV, HRTOFMS, and 2D NMR. Compounds 1, 2, and 3, showed good inhibitory activities ($IC_{50}$) of 175.4, 94.4, and 126.6 ${\mu}g/mL$ respectively, whereas a reversible ADH inhibitor, 4-methylpyrazole, showed the $IC_{50}$ of 326.6 ${\mu}g/mL$ against alcohol dehydrogenase (ADH).

• Korean Journal of Pharmacognosy
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• v.53 no.1
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• pp.29-41
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• 2022

This study was conducted to verify the availability of immature persimmon ethanol extract (IPEE) as a natural and functional ingredient in protecting inflammation and allergy of skin based on the mechanism. The major content analysis, antioxidant activities, anti-allergic activity, anti-inflammatory effect, and safety related to irritation of IPEE were evaluated. The gallic acid content per 10 mg/mL of IPEE was 0.522% (5.22 mg/g). The total polyphenol and flavonoid contents were 428.3 mg/g and 31.1 mg/g, respectively. In ABTS+ activity, DPPH ability and SOD-like activity, it showed a concentration-dependent increase, which indicated IPEE has excellent antioxidant activities. As for the anti-allergy test in RBL-2H3 cells, the IPEE showed a decrease in β-hexosaminidase secretion as the concentration increases, and IPEE tended to decrease IL-4 secretion in all RBL-2H3 cells compared to the IgE + HSA group. IPEE showed good anti-inflammatory effect in RAW 264.7 cells by decrease of NO production and inflammation cytokines (TNF-α and IL-6). Also IPEE showed non-irritant in BCOP assay. By the results of this study, the IPEE containing high tannins, had good antioxidant, anti-allergic, and anti-inflammatory effects, which indicated that the immature persimmon is considered to be a useful for the development of related functional ingredients.

• Proceedings of the Korean Society of Life Science Conference
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• 2000.09a
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• pp.96-96
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• 2000

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.4
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• pp.500-505
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• 2010

The antioxidant activity of methanol extracts from five different parts (flesh, peel, core, seed, calyx) of Jangseong Daebong persimmon (Diospyros kaki cv. Hachiya) were evaluated by determining total phenol content (TPC), DPPH radical scavenging activity (RSA), ABTS RSA, and reducing power (RP). The flesh extract gave the highest yield (92.93%) while the lowest yield was obtained from the seed (5.17%). The seed extract showed the highest total phenolic content ($76.47\pm0.009$ mg GAE/g extract), DPPH RSA ($IC_{50}=52.05\pm1.61\;{\mu}g/mL$), ABTS RSA ($IC_{50}=30.94\pm0.41\;{\mu}g/mL$) and RP ($IC_{50}=87.94\pm0.37\;{\mu}g/mL$). In addition, the calyx extract also showed high antioxidant activity. On the other hand, the core extract gave the lowest TPC and all antioxidant assays. In particular, HT-29 cells showed extensive cell death when treated with $500\;{\mu}g/mL$ of calyx extracts. Thus, these results suggest that methanolic extracts of Jangseong Daebong persimmon seed and calyx may serve as a potential source of natural antioxidant for food and nutraceutical application.