• Journal of Microbiology and Biotechnology
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• v.12 no.6
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• pp.989-992
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• 2002

Sweet persimmon (Diospyros kaki Thunb.) is widely cultivated in the southern part of Korea and its cultivation is increasing. However, anthracnose disease caused by Colletotricuhum species is one of the major hinderances to the cultivation and production of sweet persimmon. Therefore, in the current study, PCR was used to specifically detect Colletotrichum spp., based on the sequences of the ITS II regions in the rDNA. Using the sequence data, CO-1 was designated to detect Colletotrichum together the with ITS 4 primer. The result showed that a single segment of ca. 500 bp was observed only in Colletotrichum, but not in any other fungal and bacterial isolates. The annealing temperatures and template DNA quantites were also investigated to identify optimal conditions for detection. Using these species-specific primers, a unique band was obtained at annealing temperatures ranging from $55^{\circ}C\;and\;61^{\circ}C$ and template DNA levels from 10 pg- $10{\mu}g$.

• The Korean Journal of Ecology
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• v.13 no.4
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• pp.251-266
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• 1990

Extrafloral nectaries have been shown in many studies to promote mutualistic interactions between plants and insects(usually ants) that visit the glands. The insects gain sugars, water and amino acids secreted by the extrafloral nectaries and benefit the plants by reducing the damage caused by plant's inseet herbivores. Little is known about the occurrence of extrafloral nectaries in plants growing in Asia. To learn about the occurrence of extrafloral nectary bearing plants in Korea, living plants and herbarium material were examined for the glands. In addition, the cover of plants with extrafloral nectaries and the proportion of woody plants with extrafloral nectaries were measured in three forest communities on Kangwha Island. 131 species of plants belonging to 53 genera and 30 families were found to have extrafloral nectaries. These 131 species comprise about 4.0% of Korea's flora, a highet percentage of extrafloral nectary bearing plants than occurs in the studied areas of North America. Extrafloral nectary bearing plants occupied 7, 23 and 55% of the covers and comprised 15, 21 and 15% of the woody plants in the three different forests, a significant level of occurrence. Many important Korean crop plants were found to have extrafloral nectaries including : sesame (Sesamum indicum L.), squash (Cucurbita moschata Duchesne), sweet potato (Ipomoea batatas Lam), persimmon (Diospyros kaki Thunb.) cotton (Gossypium indicum Lam.), mung bean (Phaseolus radiatus L.), red bean (Phaseolus angularis W.F.), peach (Prunus persica (L) Batsch.), plum (Prunus salicina Lindl.). Many of these cultivated and wild plants may receive protection by ants and other beneficial insects that visit their extrafloral nectaries.

• Korean Journal of Plant Resources
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• v.29 no.3
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• pp.313-321
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• 2016

Persimmon has long been established as one of the major fruits in Korea. The southern parts of Korea were traditionally the pocket areas for good persimmon production; however, rising temperatures have gradually rendered the southern regions unsuitable for successful harvest. Ecology of fruit growing areas affects the productivity of various types of crops, including fruit trees such as persimmon. The quality characteristics of the fruit of persimmon cv. Dongchul grown in Gangwondo, which lies in the northern part of South Korea, were investigated. Different physicochemical, nutritional, and antioxidant properties of fruit were evaluated to assess the locational effect on the quality of persimmon fruits grown in Gangwondo. The results of this study showed that persimmon cv. Dongchul grown in Gangwondo maintains many of the physicochemical (4.33% crude protein and 4.32% crude fiber), nutritional (total mineral content: 461.51 and vitamin C content: 15.28 ㎎/100 g), and antioxidant properties (polyphenol content: 633.1 ㎎ gallic acid equivalent/100 g) those are found in other three commercial cultivars ‘Daebong’, ‘Kyengsan Bansi’, and ‘Sangju Doongsi’ grown in Korea. Overall results of this study imply that ‘Dongchul’ cultivar of persimmon could commercially be grown in Kangwondo, Korea.

• Korean Journal of Medicinal Crop Science
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• v.27 no.3
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• pp.186-193
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• 2019

Background: Astringent persimmon (Diospyros kaki Thunb. cv. Kojongsi) peels are by-products of dried persimmons. This study aimed to evaluate the antioxidant activities of Kojongsi persimmon peel (KPP) extracts prepared by 15 different extraction methods: 5 heating durations (0.5 - 2.5 h) at 3 heating temperatures (50, 70, and $90^{\circ}C$). Methods and Results: An increase in heating temperature increased the antioxidant effect of KPP extracts. Those prepared by heating at 1 h had the highest total phenol content, regardless of the heating temperature. In addition, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and cell-protective effects against $H_2O_2-induced$ oxidative stress were dependent on the total phenol contents of the extract. However, the KPP-induced increased in catalase expression was dependent on heating temperature and duration. Conclusions: These results suggest that extraction by heating at $90^{\circ}C$ for 1 h may enhance KPP's antioxidant effects, which mainly involve non-enzymatic antioxidant systems.

• Korean Journal of Plant Resources
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• v.31 no.5
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• pp.515-521
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• 2018

This was carried out to develop a chromosome-doubled (12x) persimmon that will be used as a crossing parent to select seedless persimmon cultivars with the change of the consumption trend recently. To obtain a chromosome-doubled (12x) persimmon, colchicine was applied at the meristem of seedlings in vitro derived from cross among hexaploid persimmon (Diopyros kaki Thunb.). These were treated with 0.03%, 0.05% and 0.1% colchicine respectively for doubling chromosome, and it was most effective at the concentration of 0.05% colchicine. After colchicine treatment, we conducted tests to elucidate conditions for inducing shoot and root development. As the result, the shoots grew best when cultivated at 1/2MS media plus 10 and $30{\mu}M$ zeatin respectively, and the roots grew best when cultivated at 1/2MS media after dipping for 5 seconds at 10 mM NAA+5% DMSO. We also compared seedlings that have chromosome (6x) do not doubled and crossing parents (6x) and chromosome-doubled seedlings (12x). As the result, these chromosome-doubled seedlings (12x) showed lower stomatal density and larger stomatal size.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.540-544
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• 2001

The effect of long day treatment on the growth and flower bud differentiation of persimmon tree grown in a heated plastic house was investigated. The rate of leaf sprout was 65% in the long day treatment and 71% in natural day (control). In the long day, the shoot grew 16.7 cm longer, full bloom and harvest days were shorter, fruit weight was 16% lighter, and the sweetness and firmness of fruit were lower. The photosynthesis rate in the long day treatment was higher, showing the tendency of increasing with time. However, the rate of photosynthesis increased after 1600 hours showed higher than the control. Carbohydrate accumulation in the shoot was decreased, with higher nitrogen content and lower C/N ratio in the long day. The number of flower primordia per bud was less, and the days for differentiation was longer in the long day.

• Journal of Nutrition and Health
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• v.32 no.4
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• pp.337-352
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• 1999

The effects of dried leaf powders and ethanol extract of persimmon, green tea and pine needle on lipid metabolism, lipid peroxidation and antioxidative activity were investigated in rats. Forty-nine male Spargue-Dawley rats weighing 107.8$\pm$1.8g were blocked into seven groups according to body weight. Rats were raised for four weeks with diets containing either 5%(w/w) dried leaf powders of one of three different Korea traditional teas, persimmon(Diospyros kaki Thunb), green tea(Camellia Sinensis O.Ktzc)or pine needle(pinus Koreansis Sieb. Et Zucc), or ethanol from equal amounts of each dried tea powder. Food intake, weight gain, food efficiency ratio, and weights of liver, kidney and epididymal fat were significantly higher in the green-tea-powder group, and significantly lower in the pine-needle-powder and pine-needle-extract groups. Persimmon-leaf powder was found to decrease plasma total lipid, triglyceride and cholesterol concentration by increasing fecal total lipid triglyceride and cholesterol excretions. Liver cholesterol concentration was significantly lower in the green-tea and pine-needle-extract groups. Red-blood-cell superoxide dismutase(SOD) and glutathione peroxidase(GSH-px) activities were significantly increased in rats fed green-tea extract. Liver SOD activity was increased in rats fed pine-needle powder or extract, and liver GSH-px activity was increased in rats fed greentea powder. Plasma and liver thiobarbituric acid reactive substance(TBARS) concentration were both decreased in rats fed dried leaf posers or extracts of persimmon or green tea. It is believed that high vitamin E levels in persimmon leaf, and high flavonoid, beta-carotene and vitamin C levels in green tea effectively inhibited lipid peroxidation. In conclusion, persimmon and green tea leaves were effective in lowering lipid levels and inhibiting lipid peroxidation in animal tissue, while pine needles were effective and lowering body weight gain. From these results, persimmon and green tea leaves can be recommended in the treatment and prevention of chronic discorders such as cardiovascular disease, cancer and aging. As ethanol extracts from these teas were also effecitive in lowering tissue lipid levels and inhibiting lipid peroxidation, we recommend the use of discarded tea grounds for this.

• Korean journal of food and cookery science
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• v.30 no.5
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• pp.620-630
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• 2014

Traditionally, the persimmon Gojongsi (Diospyros kaki Thunb) is peeled to make dried persimmons and the skins are thrown away. In this study, the quality characteristics of cookies containing persimmon peel powder were tested for recycling of the persimmon peels. The amounts of persimmon peel powder added to the cookies were about 0, 5, 7, 9 and 11%. The densities of the cookies of the control group and the persimmon peel powder containing experimental group were 1.25 and 1.25~1.37 respectively. The pH was 6.02 for the control group and 5.95~6.01 for the experimental group. Significant differences in the moisture content were observed between groups at 3.34 and 2.16~3.31 for the control and experimental groups, respectively (p<0.05). The spreadabilities and loss rates of the cookies increased with increasing amounts of persimmon peel powder (p<0.05). In contrast, the loss rates and leavening rate of the cookies decreased significantly with decreasing amounts of persimmon peel powder (p<0.05). The lightness of the cookies showed significant decrease (p<0.05), while the redness and yellowness increased with increasing amounts of persimmon peel powder. The hardness (kg) of the control group was 0.847 while that of the experimental group was 0.904~1.110. In the QDA, the results of sensory characteristic analysis showed that the experimental group earned 11% higher scores for color, flavor, taste, and bitterness, 7% higher for appearance and 9% higher for after taste. The consumer acceptance test revealed the experimental group to have a 7% more positive evaluation for color, favor, taste and texture than the control group. On the grounds of the experiment above, the optimal mixture ratio from the sensory test was found to be 7% persimmon peel powder in the cookies.

• Food Science of Animal Resources
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• v.36 no.1
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• pp.90-99
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• 2016

This study evaluated the effects of two Korean traditional plant extracts (Diospyros kaki THUNB. leaf; DK, and Nelumbo nucifera leaf; NN) on the fermentation, functional and sensory properties of herbal yogurts. Compared to control fermentation, all plant extracts increased acidification rate and reduced the time to complete fermentation (pH 4.5). Supplementation of plant extracts and storage time were found to influence the characteristics of the yogurts, contributing to increased viability of starter culture and phenolic compounds. In particular, the increase in the counts of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus was highest (2.95 and 1.14 Log CFU/mL respectively) in DK yogurt. Furthermore, supplementation of the plant extracts significantly influenced to increase the antioxidant activity and water holding capacity and to produce volatile compounds. The higher antioxidant activity and water holding capacity were observed in NN yogurt than DK yogurt. Moreover, all of the sensory characteristics were altered by the addition of plant extracts. Addition of plant extracts increased the scores related to flavor, taste, and texture from plain yogurt without a plant extract, as a result of volatile compounds analysis. Thus, the overall preference was increased by plant extracts. Consequently, supplementation of DK and NN extracts in yogurt enhanced the antioxidant activity and physical property, moreover increased the acceptability of yogurt. These findings demonstrate the possibility of using plant extracts as a functional ingredient in the manufacture of herbal yogurt.

• Korean Journal of Organic Agriculture
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• v.22 no.3
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• pp.413-421
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• 2014

This study was conducted into the effects of cover crops among the hairy vetch, red clover, rye, and hairy vetch+rye on the soil chemical and physical properties, and fruit yield in mature 'Fuyu' persimmon (Diospyros${\times}$kaki Thunb.) trees. The shallow-rooted red clover had poor dry matter production, resulting in the lowest coverage (66%) on the orchard floor. In contrast, the highest dry matter production observed in rye and hairy vetch+rye. Estimated N, P and K production from the cover crops were the highest on the hairy vetch+rye plots, increasing soil chemicals at a depth of 0-30 cm soil. Rye or hairy vetch+rye treatments decreased the soil bulk density and solid phase. As the hairy vetch+rye treatment increased fruit yield and sugar contents, it could be proposed as an suitable cover crop for improving productivity of persimmon trees.