• Journal of the Korean Wood Science and Technology
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• v.37 no.4
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• pp.414-420
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• 2009

We dyed traditional Korean hand-made papers (Hanji) with colorants extracted from fruits of Alnus japonica to investigate the effect of various dyeing factors (mordant, dye concentration and dyeing assistant) on colors, K/S values and light fastness of the dyed Hanji. The dyed hanji had brown color. The K/S value of dyed Hanji was increased by mordanting with alum and copper acetate. $a^*$ and $b^*$ value of dyed Hanji was decreased slightly by mordanting with alum and Iron(II) chloride. The K/S value and $b^*$ of dyed Hanji increased with increasing concentration of dye, but $L^*$ value of dyed Hanji decreased. The K/S value of dyed Hanji was also increased by fixing agent. When Hanji was mordanted with Iron(II) chloride and was not mordanted, use of fixing agent resulted in greater increase of K/S value. Use of fixing agent resulted in poor light fastness. When fixing agent was used, mordanting with copper acetate resulted in smaller color difference than mordanting with alum after aging test.

• The Korean Journal of Food And Nutrition
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• v.28 no.4
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• pp.728-736
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• 2015

Cronobacter species (Cronobacter spp.), previously known as Enterobacter sakazakii, are gram negative food borne pathogenic bacteria. They pose a very high risk of infection to neonates and immuno-compromised individuals and can affect the human central nervous system. Consequently, survivors often suffer from severe neurological impairment including hydrocephalus, quadriplegia, and developmental delays. Cronobacter spp. were not only isolated from plant food and products such as cereals, fruits, vegetables, legume products, herbs, and spices but also from animal source foods such as milk, meat, fish, and products made from these foods. Therefore, rapid detection of Cronobacter spp. is essential for food safety. Many detection methods have been developed since the Cronobacter spp. were first reported. However, the development of more rapid, sensitive, and easy-to-use detection methods for the Cronobacter spp. is required. In this review, our aim was to study and compare the available detection methods for Cronobacter spp., including culture-based, molecular biology-based, and immunology-based methods. This study will contribute to the development of new and rapid detection method for Cronobacter spp.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1045-1051
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• 1996

The influence of electrolyzed acid-water (oxidation-reduction potential (ORP): above 1,150 mV, pH : 2.5) on the survival of some microorganisms was investigated. It was observed that the ORP of electrolyzed acid-water was kept at the level of above 1,000 mV for 15 days at room temperature. Escherichia coli. Salmonella typhi, Staphylococcus aureus and Saccharomyces cerevisiae were not detected after 10 to 40 min in electrolyzed acid-water. However, Bacillus cereus showed higher tolerance to electrolyzed acid-water than other test microorganisms. After 60 min of inoculation, only 0.4% of initial population remained. The investigation of surface sterilization effect on some vegetables was carried out too. Total count of cabbage, Chinese cabbage and kale were reduced to below 3% of initial count, and no coliform was detected after 20 to 60 min of immersion in 5 volumes of electrolyzed acid-water. In the lettuce, total and coliform counts were reduced to 90% and 2% of initial population. This study shows that the electrolyzed acid-water has a potential for the sterilization of food products such as vegetables and fruits which cannot be thermally sterilized.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.3
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• pp.427-432
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• 2005

This study was performed to investigate the effect of natural plant extracts on acetylcholinesterase (AChE) activity and the free radical scavenging activity. The methanolic extracts of plants were tested for AChE inhibitory activity using Ellman's colorimetric method in 96-welled microplates and antioxidant activity as the scavenging effect of 1, 1-diphenyl-2-picryl hydrazyl radical (DPPH). The results showed that AChE activities were inhibited (about 20-30%) in whole plant extract of Daucus carota var. sativa, Hypericum erectum and Fragaria yezoensis. AChE activities were inhibited (about 32-34%) in stems extract of Gingko biloba and leaves extract of Rhododendrondron yedoensa var. poukhanense. Fruit extract of Zanthoxylum schinifolium inhibited (about 18%) AChE activity. And the DPPH scavenging effects as antioxidant activity were similar to L-ascorbic acid in whole plant extract of Fragaria yezoensis and fruits extract of Comus officinalis.

• Korean journal of applied entomology
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• v.53 no.3
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• pp.209-215
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• 2014

This study was performed to monitor the seasonal occurrence of Pseudococcus comstocki (Kuwana) by using pheromone traps and to test a mating disruption technique to control this pest in pear orchards. We compared the attractiveness of rubber septa loaded with 1.5 and 3.0 mg of the pheromone, 2,6-dimethyl-1,5-heptadien-3-yl acetate. A total of 1,021 and 1,431 males were caught in traps baited with 1.5 mg and 3 mg of the pheromone, respectively. The numbers of males caught were not affected by trap color, although yellow traps were more attractive than white traps. In 2012, P. comstocki males were captured between June and October, with peaks in late June, early August, and late September. In 2013, the males were trapped between June and October, with peaks in middle June, late July, and late September. In pheromone mating disruption tests, catches were reduced by 17.7, 65.3, and 62.9% in orchards treated with 450, 900, and 1,350 mg per 10 a of the pheromone, respectively. At harvest, 3.4, 2.9, and 4.8% of fruits in orchards treated with 450, 900, and 1,350 mg per 10 a were damaged by P. comstocki, while 9.5% were damaged in the control orchard.

• Food Science and Preservation
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• v.21 no.2
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• pp.206-214
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• 2014

In this study, the characteristics of alcohol fermentation using Elaeagnus multiflora juice were studied under static fermentation condition in an effort to develop new types of functional wine. After 9 days of fermentation at $25^{\circ}C$, the pH, soluble solids, reducing sugar, viable cell numbers, and alcohol contents were shown to be 3.32~3.33, $7.8{\sim}9.0^{\circ}C$, 29.84~31.05 g/L, 7.26~8.73 cfu/mL, and 11.0%, respectively. The heat treated juice exhibited significantly higher antioxidant activity than untreated juice while the soluble phenolic and flavonoid contents became higher. Also, the fermented wine after the heat treated at $120^{\circ}C$ for 30 min contained free sugar such as fructose (0.42 g/L) and glucose (0.09 g/L), major organic acids such as lactic acid (7.32 g/L), malic acid (2.59 g/L), succinic acid (2.16 g/L), and oxalic acid (3.08 g/L), and major flavanols and phenolic acids such as catechin (99.45 mg/L), epicatechin (264.55 mg/L), epigallocatechin (82.19 mg/L), gallic acid (6.44 mg/L), and salicylic acid (60.53 mg/L). In addition, DPPH radical and ABTS radical scavenging activities and FRAP assay results were 70.47%,, 65.93%, and 1.254, respectively. These results suggest that it is possible to produced a new type of wine using Elaeagnus multiflora fruits.

• Korean Journal of Agricultural Science
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• v.14 no.1
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• pp.16-25
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• 1987

Colletotrichum acutatum, C. coccodes, C. dematium and C. gloeosporioides were detected in seed samples of red pepper (Capsicum annuum). C. dematium and C. gloeosporioides were the predominant species, maximum seed infection of the species in some samples were 84% and 28%, respectively. C. acutatum and C. coccodes were recorded only in low percentages of 1-2. The blotter method proved more suitable for detecting Colletotricum spp. than the deep freezing blotter or agar plate methods. Plating of seed components showed that C. dematium and C. gloeosporioides were recovered more frequently from seed coat, and decreasing amounts of infection were observed in the endosperm and cotyledon. Seed-borne C. dematium and C. gloeosporioides caused seed rot, damping-off, seedling blight and brown discoloration of cotyledon and hypocotyl when infected seeds were sown in agar of test tube or in soil. Inoculation experiments showed that C. acutatum was pathogenic to red fruit of red pepper and C. coccodes was highly pathogenic to red fruit and weakly pathogenic to leaf of the plant. C. dematium was highly pathogenic to leaf and green fruit and C. gloeosporioides was pathogenic to not only leaf but also green and red fruits. Host range of the four seed-borne species of Colletotrichum was also investigated.

• Food Science and Preservation
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• v.7 no.4
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• pp.409-413
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• 2000

Previously, the methanolic extracts of thirty Korean medicinal plant seeds were screened for tyrosinase inhibitors using a rapid and simple TLC method, which was superior to a conventional spectrophotometrical in vitro assay. As a result, the methanolic extracts of Thuja orientalis seeds was found to have strong tyrosinase inhibitory activity. To isolate active tyrosinase inhibitors, the seeds were defatted with n-hexane under reflux, and then extracted twice with methanol under reflux at 90$^{\circ}C$. The methanolic extract was evaporated to a small volumn in vacuo, and then successively fractionated with ether, ethyl acetate and n-butanol. The ether extract showing significant tyrosinase inhibitory activity was solubilized with 5% NaHCO$_3$and then acidified with 6N HCI. The ether souble acidic fraction was successively ohromatographed on silica gel, Sephadex LH-20 and preparative TLC. Among four compounds isolated, two of them showed stronger tyrosinase inhibitory activity, comparable to that of L-ascorbic acid (IC$\sub$50/=28$\mu\textrm{g}$/$m\ell$). These results suggest that Thuja orientalis seeds may be useful as potential sources of antibrowning agents in fruits and vegetables, and anti-melanoma agents in cosmetics and phamaceuticals.

• Applied Biological Chemistry
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• v.49 no.3
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• pp.209-214
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• 2006

Various varieties of mulberry fruit and wines were investigated to determine their chemical properties and fermentation characteristics. Mulberry wines were manufactured with 'Cheongnosang', 'Cheonhyunosang', 'Deokcheonsang', 'Hwachosipmunja', 'Hwanyoupdaeyoup', 'Jasan', 'Mansaengbaeckpinosang', 'Palcheongsipyung', 'Sabangso' and 'Susungppong'. The factors for wine fermentation and quality such as soluble solids, polyphenol and organic acids were analyzed. The contents of soluble solid, reducing sugar and polyphenol, which were affected significantly by each other, were higher for 'Hwanyoupdaeyoup', 'Jasan' and 'Palcheongsipyung' mulberry than other varieties. Organic acids such as citric, malic, succinic and acetic acid were detected in the mulberry fruits. 'Palcheongsipyung' mulberry fruit had a higher content of souble solids $(14.6^{\circ}Brix)$ and polyphenol compounds (2.15 mg/ml). After fermentation, 'Palcheongsipyung' mulberry wine showed the lowest acetic acid in 3.23 mg/ml and the highest citric acid in 12.3 mg/ml. From these results, 'Palcheongsipyung' mulberry fruit was the most suitable for the fermentation of mulberry wine.

• Research in Plant Disease
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• v.11 no.1
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• pp.21-27
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• 2005

It was confirmed that anthracnose pathogen, Colletotrichum acutatum, could specifically grow on PDA amended with $100\mu\textrm{g}$ /ml of ampicillin and tetracycline, and 100 $100\mu\textrm{g}$/ml of mixture with carbendazim and diethofencarb. There was a positive correlation between the number of colony enumerated on semi-selective media and the disease severity on pepper fruits caused by C. acutatum. Using semi-selective media for C. acutatum, the number of pathogen on soil and plant debris infected by anthracnose pathogen was investigated. In plant debris, the colony number of C. acutatum was more than in soil. For the identification of colony appeared on semi-selective media, 10 isolates were selected randomly. They were identified as C. acutatum through PCR using C. acutatum-specific primer.