• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.146-152
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• 2011

In the course of a study in relation to the production of taste, and functional enhancements in root crop chips, which were prepared by soaking dried yam slices in fruit juices, we investigated the physiological characteristics and biological activities of 8 different commercially available juices including; apple, omija (fruit of Maximowiczia typica), grape, wild grape, orange, tomato, red ginseng and black garlic juice. The average water contents, pH, brix and acidity of the juices used were $85.59{\pm}5.80%$, $3.90{\pm}0.64$, $12.19{\pm}4.70%$, and $0.49{\pm}0.19%$, respectively. The polyphenol content of black garlic and grape juice were 1.50 and 1.21 mg/ml, respectively, and those were higher than the average content (0.57 mg/mL) of the juices. Evaluation of anticoagulation activity showed that only omija juice has a strong thrombin inhibition, which is comparable to that of aspirin (1.5 mg/mL). Omija, grape and orange juice all exhibited antibacterial activity, but no antifungal activity. The 8 different juices, and in particular grape and black garlic juice, showed strong antioxidant activity in DPPH and ABTS radical scavenging activity assays, with wild grape juice demonstrating potent nitrite scavenging activity. These results suggest that omija, grape and black garlic juice can be used as soaking solutions to produce taste, and other functional enhancements, for root crop chips.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.6
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• pp.36-42
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• 2012

The empty fruit bunch fibers(EFB) of oil palm were examined for optimal utilization of the EFB fibers. The EFB fibers were obtained by shredding EFB, followe by removal of fines. The surface properties of the fibers were modified with various pre-treatments, such as hot water extraction, the soaking treatments with NaOH, $ClO_2$ and n-hexane. The changes in the fiber surface were examined with FT-IR method, which showed the changes in chemical compositions such as pectin, lignin, and etc. according to the pre-treatment methods. And the z-directional tensile testing of the fiber mold made of the treated EFB fibers showed the changes in the bonding strength by the pre-treatments. The fiber mold made of EFB fibers treated with $ClO_2$ showed the greater increase in the tensile energy absorption although the NaOH treatment resulted in the severer impact on the EFB fibers.

• Mycobiology
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• v.33 no.3
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• pp.163-165
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• 2005

In April 2002 and 2003, soft rot on fruit of eggplant (Solanum melongena) caused by Choanephora cucurbitarum was observed in the experimental fields at Gyeongnam Agricultural Research and Extension Services in Korea. The disease began with water-soaking and dark-green lesions, and then the infected tissues were rapidly rotten. Sporangium was subglobose in shape and sized $40{\sim}130\;{\mu}m$. Monosporous sporangiola were elliptic, fusiform or ovoid, brown in color, and measured as $12{\sim}20\;{\times}\;6{\sim}14\;{\mu}m$. Sporangiospores having three or more appendages were elliptic, fusiform or ovoid in shape, dark brown or brown in color, and sized $14{\sim}20\;{\times}7{\sim}16\;{\mu}m$. The fungus grew well on potato dextrose agar between 15 and $40^{\circ}C$ and its optimum growth temperature was $30^{\circ}C$. Based on morphological characteristics, the causal fungus of the fruit soft rot of eggplant was identified as C. cucurbitarum. This is the first report on the soft rot of S. melongena caused by C. cucurbitarum in Korea.

• The Plant Pathology Journal
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• v.19 no.5
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• pp.266-268
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• 2003

In 2002, sooty mold was observed on persimmon (Diopyros kald) from the Jinju Agricultural Products Wholesale Market in Gyeongnam, Korea. The lesion of the sooty mold usually appeared as scars or wounds formed on the surface of the fruits. The symptom started with water soaking lesion, then the fruit softened rapidly. Colony of the causal pathogenic fungus was dark green in color on potato dextrose agar. The diameter of growing hyphae was 1-2 $\mu\textrm{m}$. The mostly one-celled conidia were ovoid, lemon or cylinder in shape, blastophores, and sized 46-132 $\mu\textrm{m}$. Erected conidiophores were long-branched chains and their lengths varied from 24 to 346 $\mu\textrm{m}$ with 2-5 $\mu\textrm{m}$ width. The optimum temperature for mycelial growth was about 2$0^{\circ}C$. Based on their mycological characteristics, the fungus was identified as Cladosporium cladosporioides. This is the first report in Korea of the sooty mold of persimmon caused by the said fungus.

• Korean Journal of Food Science and Technology
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• v.20 no.1
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• pp.95-99
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• 1988

The changes of texture, composition of cell wall polysaccharides, polygalacturonase (PG) activity and soaking effect during preserving of persimmon at various tempoeratures were estimated for the purpose of investigating the softening characteristics of persimmon fruit. The softening of persimmon was most promoted at $25^{\circ}C$, where in the higher temperature, at $45^{\circ}C$ it was inhibited. During softening adhesiveness increased, cohesiveness and gumminess decreased. This phenomenon was obvious at $25^{\circ}C$. By soaking in water at $50^{\circ}C,\;70^{\circ}C$ for 30 minutes PG activity and softening was inhibited. Ionically associated pectin (IAP) and covalently bounded pectin (CBP) fractionated from crude cell wall of fresh persimmon were respectively degraded about 60% by PG curde enzyme of softened persimmon. And the degraded ratio of polysaccharides composed of pentose and hexose was very similar to that of polyuronide.

• Korean Journal Plant Pathology
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• v.13 no.3
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• pp.145-151
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• 1997

An unusual young fruit rot of apple caused by two species of Phytophthora was epidemic from late May to early July of 1996 in Andong, Uisung and Chungwon areas of Korea. The disease spread to over 30 apple orchards in the areas and percent of the infected tree and fruit was ca. 10~90% and 1`15%, respectively. Water soaking lesions or spots on leaves and shoot blight were also developed by the pathogen. Among 39 isolates collected, 25 were identified as P. cactorum and the others were as zp. cambivora on the basis of their distinctive morphological characters. While the former fungus was homothallic, all isolates of the latter were A1 mating types. Koch's postulate was fulfilled. Both fungi showed strong pathogenicity not only to young fruits, leaves and shoots of apple but also to those of pear and peach. Several vegetables tested did not show symptoms even by wound inoculation. An Occurrence of young fruit rot of apple caused by Phytophthora has not been reported in Korea, especially, P. cambivora has not been recorded previously as the causal agent of the disease in the world.

• Research in Plant Disease
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• v.11 no.2
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• pp.204-207
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• 2005

A Rhizopus soft rot caused by Rhizopus stolonifer occurred on Momordica charantia at Daesan-myon, Chang-won city, Gyeongnam province from 2003 to 2005. The disease usually started from wound on fruit with water-soaking lesions. The lesion rapidly expanded and softened. The fungal mycelia grew vigorously and sporangia, sporangiophores, and stolons were formed on surface of the fruit. Spoyangiophores were $15\~30{\mu}m$ in width. Sporangia were globose or hemispheric and $90\~180{\mu}m$ in size. The color of sporangia was white and cottony at first and turned to brownish black with many spores at maturity. Columella were hemispheric and $80\~150{\mu}m$ in size. Sporangiospores were irregular round or oval, brownish-black streaked and $7\~18{\times}6\~12{\mu}m$ in size. The optimum temperature for mycelial growth of the fungus on PDA was $25^{\circ}C$. On the basis of mycological characteristics and pathogenicity to host plants, the causal fungus was identified as Rhizopus stolonifer (Ehrenberg ex. Fr,) Lind. This is the first report of Rhizopus soft rot on M. charantia caused by R. stolonifer in Korea.

• Journal of Bio-Environment Control
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• v.15 no.1
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• pp.91-99
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• 2006

This study was conducted to determine the influence of postharvest dipping treatment with aminoethoxyvinylglycine (AVG) on ethylene production and composition of non-cellulosic neutral sugars in cell walls of 'Tsugaru' apple fruits during storage. Fruits were harvested on August 20, soaked in AVG 50 and 75 $mg L^{-1}$ solution for 5 minutes, and stored in cold storage chamber at $0{\pm}1^{\circ}C$ for 60 days. Fruit quality factor, ethylene productions, and cell wall component changes were investigated at 20 days interval. As a result, the fruit firmness and acid content were much higher in AVG treated fruits than those of untreated one during 60 days of cold storage. Ethylene production of AVG treated fruits was reduced to the level of 1/10 compared with untreated one. As to the change of non-cellulosic neutral sugars in the cell walls of 'Tsu- garu' fruits, the major sugar was arabinose and galactose in water, CDTA and $Na_2CO_3$ soluble fractions. The content of arabinose and galactose in untreated fruits increased as the softening of fruits was in progress, but the fruits treated with AVG showed a little change during storage, so it is predicted that these two cell wall compositional sugars were not solubilized by the treatment of AVG. Accordingly, the marketability of 'Tsu- garu' fruits could remarkably increase when soaking the fruits in AVG solution after harvest.

• Research in Plant Disease
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• v.22 no.1
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• pp.18-24
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• 2016

This study was conducted to elucidate the cultural and pathogenic characteristics of Cladosporium cucumerinum PT1 and resistance of 81 commercial cucumbers (Cucumis sativus). Cucumber leaves and fruits appeared as scab were collected from a plastic film house located in Pyeongtaek, Gyeonggi-province, Korea in late March, 2015. A casual fungus was isolated from the diseased fruits on potato dextrose agar and it was identified as C. cucumerinum PT1 based on the morphological characteristics. To find out the effect of wounding and fruit size on the development of cucumber scab, small (<10 cm long), medium (10 to 20 cm long), and large (>20 cm long, commercially mature fruit) size cucumber fruits were harvested, C. cucumerinum PT1 pathogens were inoculated with a single droplet of suspension ($1{\times}10^5$ spores/ml) on wounded or unwounded cucumber fruits. Small fruits were completely damaged with showing severe water-soaking symptoms and fast pathogen growth regardless of wounded or unwounded. Meanwhile slight water-soaking symptoms on medium and large size fruits occurred and disease development into plant tissues was observed only on wounded fruits. Disease resistance of 81 commercial cucumber cultivars was evaluated on third-stage seedlings and small fruits by inoculating suspension ($1{\times}10^5$ spores/ml) of C. cucumerinum PT1. As a result, mini and pickling cultivar groups were resistant, 'Cheoeumcheoreom' cultivar was symptomless and the other cultivars were resistant to medium resistant. On the other hand, most of cucumber cultivars belonging to the other groups were susceptible. Disease resistance of cucumber against cucumber scab was significantly different among cultivars and a few cucumber cultivars showed different disease resistant responses to two bioassay methods using seedlings and small fruits. Therefore, to screen scab resistance in cucumber, a test using both fruits and seedlings is advisable. We think that the selected resistant cultivars can be used to control cucumber scab effectively under the farmhouse condition.

• Research in Plant Disease
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• v.13 no.3
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• pp.157-163
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• 2007

Hot water treatment that is the most appropriate seed disinfection method for organic vegetable farming was evaluated in this study. Among the leafy vegetable seeds lettuce that was the most sensitive to hot water was suitable to treat at $45^{\circ}C$ for 25 min, while Chinese cabbage and radish seeds were optimally treated at $50^{\circ}C$ for 25 min. The treatments resulted in similar or higher seed germination rate than non-treated seeds and promoted plant growth. In addition, fungi such as Alternaria, Aspergillus, Penicillium, or Mucor grown on the seeds were suppressed over 90% and the bacterial growth on lettuce seeds reduced 98.5% by the treatment. Among the fruit vegetable seeds pumpkin that was vulnerable to hot water was suitable to treat at $50^{\circ}C$ for 15 min, while cucumber and hot pepper seeds revealed optimum treatment at $50^{\circ}C$ for 25 min as chinese cabbage and radish. The treatment also showed similar or higher seed germination rate and growth than non-treated seeds. Furthermore, fungi such as Rhizopus, Aspergillus, Penicillium or Mucor grown on the seeds reduced from 72.0% to 95.4%. The bacterial growth on cucumber and red pepper seeds was suppressed from 65.5% to 86.0% by the treatment. Results indicated that the hot water treatment is practical for disinfection of organic vegetable seeds and the optimum temperature and soaking time varied among the seeds.