• 대한한의학회지
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• 제24권1호
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• pp.141-154
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• 2003

Objectives : This study was undertaken to define the effect of Diospyros kaki L. Radix or Diospyros kaki L. Folium on phenylephrine-induced arterial contraction and the mechanism of Diospyros kaki L. Radix or Diospyros kaki L. Foliuminduced relaxation. Methods : In order to investigate the effect of Diospyros kaki L. Radix or Diospyros kaki L. Folium on contracted rabbit carotid arterial strips, transverse strips with intact or damaged endothelium were used for the experiment using organ bath. Diospyros kaki L. Radix or Diospyros kaki L. Folium extract was infused into contracted arterial strips induced by phenylephrine. To analyze the mechanism of Diospyros kaki L. Radix or Diospyros kaki L. Folium-induced relaxation, Diospyros kaki L. Radix or Diospyros kaki L. Folium extract was infused into contracted arterial strips induced by phenylephrine after treatment with indomethacin, $N{\omega}-nitro-L-arginine$, methylene blue or tetraethylammonium chloride, and $Ca^{2+}$ was infused into contracted arterial strips induced by phenylephrine after treatment of Diospyros kaki L. Radix or Diospyros kaki L. Folium in a $Ca^{2+}$-free solution. Results : Diospyros kaki L. Radix or Diospyros kaki L. Folium showed relaxation effect on arterial strip with endothelium contracted by phenylephrine, but in the strips without endothelium, Diospyros kaki L. Radix or Diospyros kaki L. Folium-induced relaxation was significantly inhibited. The endothelium-dependent relaxation induced by Diospyros kaki L. Radix or Diospyros kaki L. Folium was decreased by pretreatment with $N{\omega}-nitro-L-arginine$ or methylene blue but it was not observed in the strips pretreated with indomethacin or tetraethylammonium chloride. When $Ca^{2+}$ was applied to the strips which were contracted by phenylephrine in a $Ca^{2+}$-free solution, arterial contraction was increased. However, pretreatment with Diospyros kaki L. Radix or Diospyros kaki L. Folium inhibited contractile response to $Ca^{2+}$. Conclusions : Diospyros kaki L. Radix or Diospyros kaki L. Folium may suppress influx of extra- cellular $Ca^{2+}$ through the formation of nitric oxide in the vascular endothelial cells.

• 대한한의학방제학회지
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• 제29권4호
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• pp.181-189
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• 2021

Objectives : The calyx of Diospyros kaki Thunb. has usually been used to treat obstinate hiccup. This study investigated the protective effects of Diospyros kaki using C2C12 myoblasts of H₂O₂-induced oxidative stress. Methods : Cell viability and cytotoxicity were determined by MTT assay. The level of reactive oxygen species (ROS), malondialdehyde (MDA), and reduced glutathione (GSH) were measured by using optical properties. Results : The calyx of Diospyros kaki Thunb. extract showed no toxicity to C2C12 myoblasts until 20 ㎍/mL concentration and increased cell viability compared to the H₂O₂ treated group. The calyx of Diospyros kaki Thunb. extract inhibited the production of ROS and MDA at all concentrations. In addition, the calyx of Diospyros kaki Thunb. extract increased the concentration of GSH. Conclusion : This study provides that the calyx of Diospyros kaki Thunb. can be used as a potential material that exhibit antioxidative and protective effects on H₂O₂-induced oxidative stress in C2C12 Myoblasts.

• Journal of Microbiology and Biotechnology
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• 제18권2호
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• pp.314-321
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• 2008

Acaricidal effects of materials derived from Diospyros kaki roots against Dermatophagoides farinae and D. pteronyssinus were assessed using impregnated fabric disk bioassay and compared with that of the commercial benzyl benzoate. The observed responses varied according to dosage and mite species. The $LD_{50}$ values of the chloroform extract of Diospyros kaki roots were 1.66 and $0.96{\mu}g/cm^2$ against D. farinae and D. pteronyssinus. The chloroform extract of Diospyros kaki roots was approximately 15.2 more toxic than benzyl benzoate against D. farinae, and 7.6 times more toxic against D. pteronyssinus. Purification of the biologically active constituent from D. kaki roots was done by using silica gel chromatography and high-performance liquid chromatography. The structure of the acaricidal component was analyzed by GC-MS, $^1H-NMR,\;^{13}C-NMR,\;^1H-^{13}C$ COSY-NMR, and DEPT-NMR spectra, and identified as plumbagin. The acaricidal activity of plumbagin and its derivatives (naphthazarin, dichlon, 2,3-dibromo-1,4-naphthoquinone, and 2-bromo-1,4-naphthoquinone) was examined. On the basis of $LD_{50}$ values, the most toxic compound against D. farinae was naphthazarin $(0.011{\mu}g/cm^2)$ followed by plumbagin $(0.019{\mu}g/cm^2),$ 2-bromo-1,4-naphthoquinone $(0.079{\mu}g/cm^2)$, dichlon $(0.422{\mu}g/cm^2)$, and benzyl benzoate $(9.14{\mu}g/cm^2)$. Additionally, the skin color of the dust mites was changed from colorless-transparent to dark brown-black by the treatment of plumbagin. Similar results have been exhibited in its derivatives (naphthazarin, dichlon, and 2-bromo-1,4-naphthoquinone). In contrast, little or no discoloration was observed for benzyl benzoate. From this point of view, plumbagin and its derivatives can be very useful for the potential control agents, lead compounds, and indicator of house dust mites.

• 식물조직배양학회지
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• 제27권1호
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• pp.51-55
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• 2000

감나무 (Diospyros kaki Thunb.)의 기내번식에 효과적인 배지 및 생장조정제를 구명하고자 일목계차랑 (Ichikikeijiro), 도근조생 (Tonawase), 평핵무 (Hiratenenasi) 3품종을 공시재료로 하여 시험한 결과, 신초의 생존에 가장 효과적인 배지는 MS 배지였으며 MS 배지내 질소원의 함량을 1/2∼1배로 조정한 경우가 신초의 증식 및 신장에 효과적이었다. 1/2N-MS배지에 2 mg/L zeatin 처리시 0.9 cm로 가장 많은 신초 신장을 보였고, 5 mg/L 처리시 증식된 신초수가 6.2개로 가장 많았다. 증식된 신초의 발근은 동일 배지에 1 mg/L IBA 처리시 가장 효과적이었다.

• 생약학회지
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• 제45권2호
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• pp.181-185
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• 2014

This study was carried out to investigate the acute toxicity of the bark of Diospyros kaki (Ebenaceae) in mice. The aqueous extract of the bark of Diospyros kaki (AEDK) was administered orally at a doses of 5 mg/kg, 50 mg/kg, 300 mg/kg and 2,000 mg/kg. In this study, number of deaths, clinical signs, body weights and pathological examinations were investigated after administration of AEDK. There were neither dead animals nor significant changes of body weights during the experimental period. In addition, no differences were found between control and AEDK treated groups in clinical signs, organ weights and gross pathological findings. AEDK did not show any toxic effect in mice.

• 생약학회지
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• 제51권2호
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• pp.139-145
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• 2020

The leaves of Diospyros kaki Thunb. were used to treat heart disease and hypotension in traditionally East Asia. The purpose of this study is to simultaneously quantitiative analyze the content of flavonoids in leaves of D. kaki. The isolated flavonoids from the leaves of D. kaki, and the structure of the isolated flavonoids were analyzed based on ¹H and ¹³C NMR spectrum compared to literature data. Simultaneous quantitative analysis of the isolated flavonoids was validated using high performance liquid chromatography (HPLC). Results showed that the calibration curves of the flavonoid compounds were confirmed that they have a large linearity with a correlation coefficient (R²) of 0.99. In the intra-day and inter-day analysis, accuracy and precision of five compounds were measured that accuracy was 94.39 to 114.47% and precision was less than 3.00%. Content analysis showed hyperoside (1.30 ± 0.09%), astragalin (0.81 ± 0.06%), trifoline (1.58 ± 0.07%), quercetin (0.13 ± 0.02%) and kaempferol (1.33 ± 0.25%).

• 생명과학회지
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• 제23권3호
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• pp.383-388
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• 2013

본 연구는 감꼭지 추출물과 용매별 분획물에 대한 미백효과를 측정하였다. 감꼭지를 70% 에탄올로 추출한 다음 헥산, 에틸아세테이트, 부탄올, 물 순으로 순차적으로 분획하였다. 분획물 중 에틸아세테이트 분획물은 B16F10 멜라노마 세포 내에서 멜라닌 생성을 억제 효능과 티로시나아제 활성이 우수하였고, 멜라닌 생성에 관련된 단백질 발현 양상을 측정하기 위해 western blotting을 한 결과, 감꼭지 에틸아세테이트 분획물은 농도 의존적으로 무첨가군에 비해 티로시나아제, TRP-1, TRP-의 발현이 억제되었다. 이상의 결과에 따라 감꼭지 에틸아세테이트 분획물의 미백 소재로서 개발할 수 있을 것이라 사료된다.

• Mycobiology
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• 제49권1호
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• pp.54-60
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• 2021

During the screening of Korean microflora, a fungal strain (KNU-PT-1804) belonging to the genus Pestalotiopsis was isolated from persimmon tree (Diospyros kaki) bark collected from North Gyeongsang Province, Korea. The strain, KNU-PT-1804, produced smaller conidia compared with related species P. kenyana, P. neglecta, and P. telopeae. The novelty of the strain was confirmed based on phylogenetic analysis using molecular datasets of internal transcribed spacer (ITS) regions, β-tubulin (TUB2), and translation elongation factor 1-alpha (TEF1α) genes. Molecular phylogeny strongly supports that the strain is distinct from previously known Pestalotiopsis species, and we proposed the novel species, Pestalotiopsis kaki sp. nov., and provide a detailed description and illustration.

• 생약학회지
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• 제44권2호
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• pp.182-187
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• 2013

This study was conducted to investigate glutathione S-transferase(GST) activity, tyrosinase inhibitory effect and elastase inhibitory effect in persimmon calyx(calyx of Diospyros kaki Thunberg) for screening of functional materials from natural products. As a result, EtOAc extract of persimmon calyx turned out to be having tyrosinase inhibitory effect and elastase inhibitory effect. The active constituents of tyrosinase and elastase inhibitory effect were isolated from EtOAc extract of persimmon calyx. Their structure of compounds were identified as ursolic acid and (-)-daucosterol by spectroscopic evidence, respectively.

• 한국균학회지
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• 제44권2호
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• pp.118-121
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• 2016

경상북도 상주시에 서식하는 감나무 주변의 부엽토로부터 국내에 아직 기록되지 않은 진균을 분리하였다. 형태학적 및 계통학적 분석을 통해 분리한 균의 동정을 실시하였으며, 분석 결과 해당 균은 Phialophora sessilis로 확인되었다. 본 연구를 통해 P. sessilis가 국내에 존재함을 최초로 보고하였다.