• BMB Reports
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• v.32 no.6
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• pp.541-546
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• 1999

When we compared the chitinase activity of various plant sources using colorimetric or active gel-staining assay methods, the specific activity of pumpkin leaves was the highest among the samples we analyzed. The highly active chitinase from pumpkin leaves (designated PL-ChtIII) was purified to homogeneity using affinity chitin gel and HPLC Mono-Q anion-exchange cloumn chromatographies. In contrast to other members of the class III chitinase family, PL-ChtIII showed a strong binding affinity to the regenerated chitin gel column. The apparent molecular weight of PL-ChtIII was estimated to be 29 kDa on SDS-PAGE gel, while its optimum pH and temperature were shown to be pH 6.0 and $60^{\circ}C$, respectively. Analyzing the reaction products of PL-ChtIII with swollen chitin as substrate, the dimer and tetramer of N-acetylglucosamine were produced as major products in the first hour of the enzymatic reaction along with a small amount of monomers and trimers. As the reaction time increased, dimeric N-acetylglucosamine became the predominant form of reaction product.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.2
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• pp.183-189
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• 2014

We investigated noodles supplemented with functional ingredients for their antioxidant properties, including total phenol, flavonoid contents, electron donating, nitrite scavenging abilities and ferrous ion chelating effect. The total polyphenol contents of functional noodles arranged in order of decreasing concentration were kudzu (7.98%) > green tea (4.99%) > pumpkin (5.03%) > mulberry leaves (4.99%) > mugwort (4.23%) > cactus (3.57%) > kelp (3.33). The total flavonoid contents in green tea noodles were the highest as 4.35%. The electron donating ability in mugwort noodle was the highest as 12.27% at 1,000 ppm. This amount was 4.85 times than that of wheat flour noodle (2.53%). The nitrite scavenging ability of functional noodles at pH 1.2 arranged in order of decreasing concentration were green tea (66.52%) > cactus (55.12%) > kudzu (52.67%) > pumpkin (50.50%) > mulberry leaves (43.58%) > kelp (41.41%) > mugwort (37.66). The nitrite-scavenging ability of green tea noodle was lower than ascorbic acid (natural antioxidant) 77.83%, while that of green tea noodle was similar with BHT (artificial antioxidant) 69.45%. The ferrous ion chelating effect of noodles containing kelp were the highest as 27.02%. All of the experimental results showed good antioxidant property. Thus, noodles supplemented with mulberry leaves, cactus, mugwort, green tea, pumpkin, kelp or kudzu, demonstrated to have good functional effects for human health.

• Preventive Nutrition and Food Science
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• v.21 no.2
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• pp.132-137
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• 2016

Enhanced production of individual phenolic compounds by subcritical water hydrolysis (SWH) of pumpkin leaves was investigated at various temperatures ranging from 100 to $220^{\circ}C$ at 20 min and at various reaction times ranging from 10 to 50 min at $160^{\circ}C$. Caffeic acid, p-coumaric acid, ferulic acid, and gentisic acid were the major phenolic compounds in the hydrolysate of pumpkin leaves. All phenolic compounds except gentisic acid showed the highest yield at $160^{\circ}C$, but gentisic acid showed the highest yield at $180^{\circ}C$. The cumulative amount of individual phenolic compounds gradually increased by 48.1, 52.2, and $78.4{\mu}g/g$ dry matter at $100^{\circ}C$, $120^{\circ}C$, and $140^{\circ}C$, respectively, and then greatly increased by $1,477.1{\mu}g/g$ dry matter at $160^{\circ}C$. The yields of caffeic acid and ferulic acid showed peaks at 20 min, while those of cinnamic acid, p-coumaric acid, p-hydroxybenzoic acid, and procatechuic acid showed peaks at 30 min. Antioxidant activities such as 2,2-diphenyl-1-picrylhydrazyl and ferric reducing antioxidant power values gradually increased with hydrolysis temperature and ranged from 6.77 to 12.42 mg ascorbic acid equivalents/g dry matter and from 4.25 to 8.92 mmol $Fe^{2+}$/100 g dry matter, respectively. Color $L^*$ and $b^*$ values gradually decreased as hydrolysis temperature increased from $100^{\circ}C$ to $140^{\circ}C$. At high temperatures ($160^{\circ}C$ to $220^{\circ}C$), L* and b* values decreased suddenly. The $a^*$ value peaked at $160^{\circ}C$ and then decreased as temperature increased from $160^{\circ}C$ to $220^{\circ}C$. These results suggest that SWH of pumpkin leaves was strongly influenced by hydrolysis temperature and may enhanced the production of phenolic compounds and antioxidant activities.

• Korean Journal Plant Pathology
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• v.1 no.3
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• pp.173-177
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• 1985

The objective of the study is to determine differences between cucurbits in the pathogenicity of Didymella bryoniae isolated from the naturally infected seeds of cucumber and pumpkin. Primary seedling infection of cucumber(Cucumis sativus L.), oriental melon(Cucumis melo var. makuwa Makino), pumpkin(Cucurbita pepo L.) and watermelon (Citrullus vulgaris Shrad.) occurred on the radicle, hypocotyl and cotyledons and symptoms on each crop were very similar. Infection of the radicle generally caused pre-emergence rot, while infection on the hypocotyl and cotyledons provided further inoculum for infection of the first true leaves and the stem. In cross inoculation tests, all isolates of D. bryoniae could infect cucumber, oriental melon, pumpkin and watermelon at different growth stages and there were not much differences in pathogenicity or susceptibility between isolates of the pathogen and crops tested. The susceptibility of cucumber and pumpkin was markedly influenced by prevailing humid conditions.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.3
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• pp.368-374
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• 2014

We investigated the physical and cooking properties of commercial noodles supplemented with functional ingredients. RVA (rapid visco analyzer), color, water activity, texture and cooking properties were tested. Noodles containing kudzu showed the highest initial gelatinization temperatures, whereas noodle containing kelp displayed the highest peak viscosity and set back. Holding strength and final viscosity were highest in noodles containing mugwort. The L value ($94.89{\pm}0.02$) of wheat flour noodle was the highest. Among functional noodles, L value ($88.65{\pm}0.01$) and a value ($7.42{\pm}0.02$) of cactus noodle were the highest, whereas b value of pumpkin noodle was $40.81{\pm}0.03$, which was higher value than in other noodles. Water activity of cactus noodle was highest (0.455), but the difference was not significant. Cooking properties (including weight, volume, and water absorption) and turbidity of pumpkin noodles showed the highest growth rate. In terms of texture, hardness was highest ($12836.8{\pm}7.1g/cm^2$) in green tea noodles, and cohesiveness and gumminess were highest in kelp and mugwort noodles. Considerig the quality characteristics of noodles supplemented with mulberry leaves, cactus, mugwort, green tea, pumpkin, kelp or kudzu, pumpkin noodles were most stable in terms of gelatinization and cooking properties.

• The Plant Pathology Journal
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• v.16 no.4
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• pp.216-221
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• 2000

Mixed infection of watermelon mosaic potyvirus II isolated from pumpkin (WMV-P) and cucumber green mottle mosaic tobamovirus from watermelon (CGMMV-W) caused extremely severe symptoms such as progressive silting and death of watermelon plants. Single infections of either WMV-P or CGMMV-W on the same hosts produced only vein clearing and/or mosaic on the upper leaves. In cells infected with WMV-P, potyvirus-characteristic inclusions of pinwheels, scrolls and cylindrical inclusions were present in the cytosol. Parallel arrays of virus particles in the tonoplast were also common. In cells infected with CGMMV-W, virus particles occurred as stacked-bands of scattered randomly in the cytosol and vacuoles in all type cells. Many cells also contained vesiculated mitochondria with fibril-containing vesicles. Cells infected mixedly with WMV-P and CGMMV-W contained structural features that were not observed in cells infected singly with the two viruses. A particle of WMV-P potyvirus was surrounded by evenly spaced nine particles of CGMMV-W tobamovirus, which made a unique nonagon ring. The angled layers having $60^{\circ}$-$135^{\circ}$ were alternating layer, herringbone, crosshatching and ladder figures.

• The Plant Pathology Journal
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• v.15 no.6
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• pp.345-347
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• 1999

A scab disease on eggplant (Solanum melongena L. cv. Chukyang) in plastic film houses around Kimhae area in Korea during the winter season of 0998-1999. The disease started on leaves with small dark brown spots which were gradually expanded to 1 to 3 mm diameter lesions. Later, the central parts of the lesions became collapsed and detached to make holes. Dark brown mold was grown out of the lesions on the lower side of leaf. Numerous conidia were produced on the lower side of leaf. Numerous conidia were produced on the diseased leaves and appeared to be readily dispersed in the air. A fungus was isolated from the diseased leaves, and tested for Koch's postulates to prove the causal agent of the desease. The isolated fungus grew on potato dextrose agar, forming greenish black to pale brown colonies. Conidia were ellipsoidal, fusiform or subspherical, mostly one-celled but occasionally septated, and formed in long branched chains on the erected conidiophores which were pale olevaceous brown and variable in length between 12.4 and $393.4\mu\textrm{g}$. The fungus was identified as Cladosporium cucumerinum Ellis Arthur based on the above morphological characteristics examined. The optimum temperature for mycelial growth and conidial formation was about 20 to $25^{\circ}$. In addition to cucumber, the fungus was also pathogenic to watermelon, pumpkin and oriental melon. This is the first report on the scab disease of eggplant in Korea.

• The Plant Pathology Journal
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• v.22 no.3
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• pp.295-302
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• 2006

The present study addressed the efficacy of nanosized silica-silver for controlling plant pathogenic microorganisms. The nanosized silica-silver consisted of nano-silver combined with silica molecules and water soluble polymer, prepared by exposing a solution including silver salt, silicate and water soluble polymer to radioactive rays. The nanosized silica-silver showed antifungal activity against the tested phytopathogenic fungi at 3.0 ppm with varied degrees. In contrast, a number of beneficial bacteria or plant pathogenic bacteria were not significantly affected at 10 ppm level but completely inhibited by 100 ppm of nanosized silicasilver. Among the tested plant pathogenic fungi, the new product effectively controlled powdery mildews of pumpkin at 0.3 ppm in both field and greenhouse tests. The pathogens disappeared from the infected leaves 3 days after spray and the plants remained healthy thereafter. Our results suggested that the product developed in this study was effective in controlling various plant fungal diseases.

• Applied Biological Chemistry
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• v.42 no.3
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• pp.267-270
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• 1999

• Korean journal of applied entomology
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• v.20 no.4 s.49
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• pp.191-195
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• 1981

Cucurbits including pumpkin (Cucurbita pepo), gourd (Lagenariaa siceraria), cucumber (Cucumis sativus), melon(Cucumis melo) and watermelon(Cucurbita anguria) were diseased with mosaic symptoms. The causal virus was identified as watermelon mosaic virus(WMV). The WMV was transmitted by Myzus persicae Sulzer, and no seed borne virus was found. The virus caused large local lesions on the inoculated leaves of the Chenopodium amaranticolor and mosaic symptom on the upper leaves of Cucumis melo, Cucumis sativus, Lagenaria siceraria, Cucurbita anguria and Cucurbita pepo. There were no symptoms on the inoculated leaves of the Nicotiana tabacum var. Bright yellow, Nicotiana glutinosa, Vigna unguiculata. Petunia hybrida and Datura stramonium. Thermal inactivation point was $55\~65^{\circ}C$, dilution end point was $10^{-4}\;10^{-5}$ and longevity in vitro of the virus was $7\~8$ days. The virus showed positive reaction against watermelon mosaic virus antiserum in microprecipitin tests. The virus particles were flexuous rods in size of 750 nm.