• Journal of Applied Biological Chemistry
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• v.61 no.1
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• pp.25-31
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• 2018

This study investigated the effect of different $O_2$ transmission rate (OTR) of films on surface temperature, weight loss, pH, $O_2$, $CO_2$ and sensory characteristics, microbial quality, total phenolic contents and 1,1-diphenyl-2-picryl hydrazyl radical scavenging activity of fresh-cut lettuce during storage at $10^{\circ}C$ for 7 days. $80{\pm}5g$ of fresh-cut lettuce were packaged with oriented polypropylene films respectively. The OTR of packaging materials was 5,000, 8,000 and $10,000cc/m^2{\cdot}day{\cdot}atm$. Quality characteristics showed significant differences during storage. The surface temperature was averaged 13 and lower in higher OTR of films. The weight loss of lettuce ranged from 2.8 to 5.4% and the highest loss showed in $5,000cc/m^2{\cdot}day{\cdot}atm$ of film. pH was increased during storage and the highest pH was found in $5,000cc/m^2{\cdot}day{\cdot}atm$. The $O_2$ content in the packaging was decreased with increasing $CO_2$ content during storage. The lowest $CO_2$ was found in $10,000cc/m^2{\cdot}day{\cdot}atm$. As OTR was decreased, antioxidant profile of lettuce was decreased. Total aerobic bacteria showed from 5.48 to 6.59 log CFU/g. From the result of the overall sensory test, the marketability of fresh-cut lettuce stored at $10^{\circ}C$ seemed to be maintained effectively over 5 days.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.3
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• pp.211-218
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• 1982

The specific heat capacity and density of soybean oil and soy protein composing of the soybean curd were measured between $30^{\circ}C\;and\;-40^{\circ}C$. The thermal conductivity of soybean oil was measured to be 0.160 and 0.140, $W/m{\cdot}K$ at unfrozen and frozen states, respectively. The effective thermal conductivity of the soybean curd depended not only on its water content but also on its fat and protein contents.

• Journal of Applied Biological Chemistry
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• v.60 no.4
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• pp.351-355
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• 2017

Tolaasin, peptide toxin produced by Pseudomonas tolaasii, causes a brown blotch disease on the cultivated mushrooms. Tolaasin peptides form membrane pores and disrupt cellular membrane structure. Molecular actions of tolaasin consist of the aggregation of peptide molecules, binding to the cell membrane, and formation of membrane pores. Therefore, the inhibitions of any of these actions are able to suppress the blotch disease. We have isolated and identified several tolaasin inhibitors (named tolaasin inhibitory factors, TIF) from food additives. TIFs were able to suppress the blotch-formation by the pathogen inoculated to the mushrooms. In this study, TIFs were incubated under various conditions and their activities for the inhibition of tolaasin-induced hemolytic activity were investigated. Since TIFs are unsaturated carbon compounds, they were sensitive to the air exposure and light irradiation. In the anaerobic conditions, TIFs were stable and their activities were decreased by 10% for three months. However, near 90% of TIF activity was suppressed by two weeks in the presence of air and sun light. Temperature did not show any significant effects on the activity of TIF, since storages at 5, 25, $45^{\circ}C$ did not show any difference. Therefore, for the stable storage of TIF compounds, container should be designed to be dark and air-tight.

• Polymer(Korea)
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• v.35 no.1
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• pp.7-12
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• 2011

Poly(lactic-co-glycolic acid) (PLGA) is a biodegradable synthetic polymer with acceptable mechanical strength and well-controlled degradation rate. Also, it can be easily fabricated into many shapes. Silk fibroin contains powerful bioactive molecules. We fabricated natural/synthetic hybrid films using 0, 10, 20, 40 and 80 wt% of silk fibroin. Schwann cells (SCs) were seeded on PLGA/silk fibroin hybrid films and confirmed the effects of adhesion and proliferation on SCs according to the content of silk fibroin. In this study, we confirmed PLGA/silk fibroin hybrid film containing 40% and 80% of silk fibroin interrupted adhesion and proliferation of SCs. Films containing 10% and 20% of silk, however, provided suitable environment for growth and proliferation of SCs. These results suggest that silk fibroin provides suitables surface to neural cells and its proper content provides proper culture conditions to improve cell adhesion and proliferation.

• Korean journal of applied entomology
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• v.46 no.2
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• pp.325-330
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• 2007

Among various food base baiting materials, beer and macerated cucumber were the most effective to induce slug that is a troublesome pest on leafy vegetables, especially on lettuce. However, the baits attracted only but did not kill the pest. When the baits were combined with various insecticidal organic materials, a few combinations such as beer and cigarette mixture successfully induced and killed the slug in the field test. The most effective combination of beer 50ml and a cigarette contained in a small plastic box killed 25 slugs per night. While macerated cucumber 50ml and a cigarette mixture killed only 4.3 slugs. The bait of beer and cigarette mixture revealed 68.4% control value against slug damage when treated for 3 consecutive days in a lettuce cultivation greenhouse. The bait also effectively reduced the slug damage in a lettuce nursery showing 58.3% control value. The method seemed highly useful for the control of slug in the organic farming system in which application of pesticides are strictly prohibited.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.43 no.4
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• pp.381-390
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• 2017

This study was conducted to determine 16 preservatives and 18 UV filter ingredients levels in 100 sunblock products. The order of detection rates of preservatives was phenoxyethanol (n=61), benzoic acid (n=19), methyl paraben (n=11), benzyl alcohol (n=8), propyl paraben (n=7). Also the order of detection rates of UV filter ingredients was titanium dioxide (n=81), ethylhexyl methoxycinnamate (n=69), zinc oxide (n=48), ethylhexyl salicylate (n=48), bis-ethylhexyloxyphenol methoxyphenyltriazine (n=44). The content of the detected preservatives and UV filter ingredients was within maximum allowed amount established by KFDA. In addition, preservatives and UV filter ingredients, which were not labeled in the products, were detected in 31 and 2 products respectively.

• Korean journal of applied entomology
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• v.58 no.1
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• pp.69-76
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• 2019

This study was evaluated to increase the production efficiency of Gryllus bimaculatus De Geer, which are recently increasing attention as industrial insects in Korea. In this study, the hatching rate and larval period were investigated along with temperature and humidity, as well as the survival rate and ovipositional temperatures along with rearing density. The optimum relative humidity for hatching was highest at 90%, which shows the hatching rate of 90%. The highest hatching rate was 98.3% at $20^{\circ}C$. The hatching period was shortest at $35^{\circ}C$ incubation, which shows 7.1 days in average. The survival rate at 3,000-20,000 individuals in the breeding container was 34-18% after rearing for 35 days. In the effect test of feeding vegetables, the survival rate was 1.8 times and the biomass weight 2.5 times higher than that of normal individuals respectively. The number of laying eggs by temperature was highest at $25^{\circ}C$, which shows 1,710 eggs after reading for 30 days.

• Journal of Life Science
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• v.29 no.10
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• pp.1120-1125
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• 2019

The short-lived nematode Caenorhabditis elegans has been used as a model organism for many studies, including lifespan extension. To screen common seaweeds for natural anti-aging agents, the lifespan of C. elegans (N2 wild-type strain) was measured by its hatch rate, growth rate, survival rate, chemotaxis, brood size, and egg-laying time after exposure to nematode growth medium (NGM) containing seaweed extracts. Approximately 30 animals synchronized at the first larval stage were incubated until they reached their adult stages before laying their eggs and were transferred to fresh NGM every 3 days. We also identified the major active compound from the seaweed by gas chromatography-mass spectrometry and tested its optimal dose for longevity. Of 13 common seaweed species, an ethanol extract of the brown seaweed Hizikia fusiformis showed the greatest effect on hatching, growth, and survival rates. The lifespan of C. elegans was significantly expanded 1.54-fold and 1.23-fold in the presence of the ethanol extract (0.05 mg/ml) and the main active component, fucosterol (0.05 mg/ml), respectively. Exposure to the ethanol extract also increased chemotaxis 1.13-fold, decreased brood size 0.74-fold, and shortened egg-laying time 0.96-fold. These results suggest that the aquaculturable H. fusiformis may be a promising source of a diet supplement to support health care.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.27 no.3
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• pp.129-139
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• 2021

We studied the consumer preference for the packaging of "Samgyetang" retort product in order to improve its function and design. A total of 319 eligible respondents (male 175, female 144) were surveyed with a questionnaire asking on the general characteristics for the preference of the packaging function, type of retort package, packaging design, convenience, cooking method of retort product and characteristics of "Samgyetang" retort product. The collected data was analyzed using a chi-square (X²) statistical test in SPSS program. The results showed that the retort packages with opacity and microwaveable types were preferred. Also, most respondents expressed that it needs to be improved for cooking convenience. Another question results showed that the consumers are considering the taste and cost of a product more important than the brand of its product when purchasing. Based on the results of the questionnaire, the study suggested that many consumers want the convenience of packaging and product protection for high value added product. The results help to provide consumer's demand for packaging development and to provide the greatest advantages in terms of production and marketability of "Samgyetang" retort product.

• The Journal of the Korea Contents Association
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• v.22 no.7
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• pp.102-115
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• 2022

To research the changes of Ramyun in Korea, this paper was went over an historical study through the content analysis of ads. from 1963 to 2012. The study period was divided into 6 stages based on GNI(Gross National Income). The advertisements were classified into new advertisements and all ones, and the advertisements of new Ramyun were categorized with 4 ways. And the most emphasized messages of advertisements and advertising models of each periods were also examined. The total number of new advertisements was 185(3.7/y) and 650 total advertisements(13.7/year). The most emphasized messages were changed from 'taste' and 'high calorie' to 'noodles', 'function(specific nutrition)'. The advertising models were actors, comedians, popular singers, in turn. The 1960's was the period when the fewest new products were advertised to consumers most often. 1980-1996 was the period when the most new products were advertised the most. During the depresseions, all ads were more frequently and new ads were lower advertised. Above results, each period was named as follow, respectively ; the Expansion period(1963~1969), the Set-up period(1970~1979), the Competition period (1980~1987), the Bipolarization period(1988~1997), the Transition period(1998~2003), the Stabilization period(2004~2012).