• BMB Reports
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• 제32권6호
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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.

• 동아시아식생활학회지
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• 제24권2호
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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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• 제21권2호
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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.

• 한국식물병리학회지
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• 제1권3호
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• pp.173-177
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• 1985

본 연구는 자연이병된 오이와 호박 종자에서 분리한 덩굴마름병균(만고병균)의 병원성의 차이를 조사한 것이다. 오이, 참외, 호박 및 수박의 유묘에 대한 일차 감염은 유근$\cdot$배축$\cdot$자엽에 나타났으며 병징은 작물에 관계없이 비슷하였다. 유근이 병들었을때는 발아전 부패현상으로 나타났고 배축과 자엽의 감염은 제1엽과 줄기로 이어지는 접종원이었다. 교호접종시험 결과 공시된 덩굴마름병균의 모든 분리균은 오이, 참외, 호박, 수박의 종자 및 유묘에 대하여 병원성이 있었으나 분리균이나 공시작물간에는 차이가 별로 나타나지 않았다. 오이와 호박의 감수성은 다습조건에 의해서 크게 영향을 받았다.

• 동아시아식생활학회지
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• 제24권3호
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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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• 제16권4호
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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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• 제15권6호
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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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• 제22권3호
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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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• 제42권3호
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• pp.267-270
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• 1999

• 한국응용곤충학회지
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• 제20권4호
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• pp.191-195
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• 1981

모자익병징을 나타내는 호박, 박, 오이, 참외, 수박의 박과작물에서 Watermelon Mosaic Virus(WMV)를 분리동정하였다. 이병주로 부터 분리된 WMV는 복숭아혹진딧물(Myzus persicae, Sulzer)에 의해 쉽게 충매전염되었고 종자전염은 되지 않았다. 지표식물검정결과 명아주에서는 접종엽에 대형의 국부병반이, 호박, 박, 오이, 참외, 수박에서는 접종상엽에서 모자익병반이 나타났고 담배(Nicotiana tabacum, Bright yellow), 담배 (Nicotanan glutinosa), 동부, 페추니아, 독말풀에서는 반응이 나타나지 않았다. WMV isolate의 물리적 성질은 내열성 $55\~65^{\circ}C$, 내희석성 $10^{-4}\~10^{-5}$배, 내보존성 $7\~8$일간이었다. WMV isolate의 항혈청반응은 미량침강법에서 양성으로 나타났고 바이러스립자의 형태는 전자현미경검경결과 대부분이 750nm의 사상입자이었다. 이상의 시험결과로 박과 작물에서 분리한 바이러스가 WMV 임이 확인되었다.