• Journal of Korean Society of Forest Science
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• v.76 no.2
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• pp.119-126
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• 1987

This study was carried out to elucidate the desirable PEG molecular weight and it's blending methods which can promote the dimensional stabilization of Corpus controversa, Quercus variabilis and Prunus sargentii. The results may be summarized as follows: 1. PEG polymer loading in woods was affected by specific gravity of wood. And the PEG polymer loading was satisfactory except in Quercus variabilis, which shows the blending method of PEG V was proper. 2. Bulking coefficiency of PEG V was high in Corpus controversa and Prunus sargentii, and it is necessary to paint or coat water-proofing wood preservative: for high bulking coefficiency of Quercus variabilis. 3. In the treatment of PEG V, the antishrink efficiency of Prunus sargentii was 82.59% and that of Quercus variabilis 62.79%. 4. Dimensional stabilization of hardwoods did not have apparant relation with PEG blending method. 5. Judging from results, PEG-400 and PEG-1000 would be enough for dimensional stabilization of hardwood having high specific gravity if other factors are considered well.

• Korean Journal of Clinical Laboratory Science
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• v.49 no.3
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• pp.256-262
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• 2017

Essential oil from herb is known to exert pharmacological effects on the human body. In this study we investigated the antibacterial activity of 4 essential oils (teetree, rosemary, melisa, and lavender), as well as the blended mixture oil of teetree, rosemary, and melisa (TRM) on three bacteria, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Antibacterial analysis was performed using the standard disk diffusion method, and minimum inhibition concentration was determined by the broth microdilution method with different concentrations of essential oils (0.5, 1, 2 and 3 mg/mL). After incubation at $37^{\circ}C$ for 24 h, the antibacterial activity was assessed by measuring the zone of growth inhibition surrounding the disks. Herb oil with the inhibition zones showed varied values ranging from6 to 25 mm. However, the components of herb oil of TRM are as highly active as the teetree oil against pathogens, generating large inhibition zones for both gram negative and positive bacteria (13~22 mm and 8 mm inhibition zones). In the analysis for MIC, TRM showed growth-inhibitory effects at 0.0625% for S. aureus and E. coli, and 1.25% for P. aeruginosa. This result demonstrated that the anti-microbial activity of TRM was greater than a single herb oil, including oxacillin, rosemary, and teetrea. As a single herb oil, both rosemary and teetrea also had an anti-microbial effect by itself, and we can expect that the blended oil mixture may exert a synergistic effect against multidrug resistant bacteria, suggesting its future application in natural preservative agents for health food and cosmetics.

• Korean journal of food and cookery science
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• v.16 no.1
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• pp.40-46
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• 2000

The sensitivity of various pathogenic bacteria(Listeria monocytogenes, Staphylococcus aureus, Aeromonas hydrophila, Escherichia coli O157:H7 and Salmonella typhimurium) to the pine needle and green tea extracts was tested. Water extract of pine needle(PNW), 70% ethanol extract of pine needle(PNE), water extract of green tea(GTW) and 70% ethanol extract of green tea(GTE) were prepared for the test of antibacterial activty. Tryptic soy broth(TSB) containing 0∼2%(w/v) of pine needle and green tea extracts were inoculated with 10$\^$5/∼10$\^$6/ cells/ml of each bacterium and incubated at 35$\^{C}$ for 24 hours. The standard plate count method was used to measure the inhibitory effect of the extracts. Minimum inhibitory concentration(MIC) and minimum bactericidal concentration(MBC) were derived from the survival curves of pathogenic bacteria. Antibacterial activities of the pine needle and green tea extracts were compared with that of sodium benzoate, a preservative, by clear zone test. L. monocytogenes, S. aureus and A. hydrophila were completely inhibited at 0.4∼1.6% level while E. coli and S. typhimurium were very resistant to the pine needle extracts. Green tea extracts completely inhibited all strains tested at 0.2∼1.0% level and bactercidal to all strains except L. monocytogenes at 0.5∼2.0% level. Antibacterial activities of pine needle and green tea extracts were stronger than that of sodium benzoate. The order of antibacterial activities of pine needle and green tea extracts to the pathogenic bacteria was GTE > GTW > PNE > PNW. This result suggests that green tea extracts can be used as an effective natural antibacterial agent in food.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.397-406
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• 1998

Hen egg white lysozyme (HEWL) is very valuable as a natural preservative in food processing due to its selective bactericidal activity. HEWL which traditionally isolated by crystallization or freeze drying was simply separated from 13 different hen egg white (HEW) proteins by a single-step ultrafiltration. Freeze dried HEW (0.25%, w/v) dissolved in a citrate-phosphate buffer (pH 4.6) was ultrafiltered with a PM30 membrane under various operating conditions, by changing concentration, temperature, transmembrane pressure $({\triangle}P_T)$, and stirring speed. Optimum separation conditions were decided when maximal flux was obtained. Under the optimum separation conditions, the effect of membrane material and fouling on flux as time passed as well as lysozyme concentration, protein concentration, specific activity (SA) in the permeate were measured. Best separation conditions of HEWL with PM30 membrane were sample concentration 0.25%, temperature $35^{\circ}C$, ${\Delta}P_T\;30\;psi$, and stirring speed 300 rpm. During the first 12 min, the flux of YM30 was higher, but at the steady-state it was lower than that of PM30. The SA of the PM30 permeate was over 2 times higher in spite of the lysozyme and protein concentration being lower than that of YM30 permeate. The flux of 5 times used PM30 decreased 30% compared to a new PM30, but both had the same tendency in flux decrease when time passed. Both of them reached a steady-state after 35 min and remained at 70% of the initial flux. In the PM30 permeate, the lysozyme concentration and SA were 110 units/mL and 2,821 units/mg protein, respectively. Therefore, PM30 membrane separation was very effective for separation of antimicrobial lysozyme.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.4
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• pp.65-73
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• 2008

Due to the amendment of the Act for Urban Parks in 2005, local governments have to establish long-range plans for securing and managing urban parks and green areas. This study aims to propose a method of setting priorities for green areas of land to be preserved before the development stage through the introduction of the concept of Green Infrastructure Assessment, and provide basic data to establish the network of urban parks and green areas by applying the GIA method to the city of Daejeon. The concept of GIA and the process of analysis have been drawn as a result of literature research and case studies. The results of this study show that an introduction of the GIA concept to set park and open space planning promotes the connection of the city planning process as well as presents very a reasonable source to facilitate sustainable development. Also, other results present a priority ranking for protection of parks and green areas as well as a means to manage potential focus areas. This study, does have research limitations such as a limited study area, scale, and conflicts between domestic and foreign computing data. Further studies need to set the planning process and examine the index survey to apply this method to various situations and areas.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.7
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• pp.1106-1111
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• 2004

This study was performed to investigate the antimicrobial effect of the Indigofera kirilowii extracts against food-borne pathogens. The Indigofera kirilowii was extracted with methanol at room temperature, and fractionation of the methanol extract from Indigofera kirilowii was carried out by using petroleum ether, chloroform, ethyl acetate, and methanol, respectively. The antimicrobial activity of the Indigofera kirilowii extracts was determined using a paper disc method against food-borne pathogens and food spoilage bacteria. The ethyl acetate extract of Indigo/era kirilowii showed the highest antimicrobial activity against Staphylococcus aureus and Shigella dysenteriae. The water extract of Indigofera kirilowii showed relatively low antimicrobial activity against microorganisms used in this experiment. The synergistic effect has been found in combined extracts of Indigofera kirilowii and Pulsatilla koreana as compared to each extract alone. The growth inhibition curve was determined using ethyl acetate extracts of Indigofera kirilowii against S. aureus and S. dysenteriae. The ethyl acetate extract of Indigofera kirilowii showed strong antimicrobial activity against S. aureus at the concentration of 4,000 ppm. The 4,000 ppm of ethyl acetate extract from Indigofera kirilowii retarded the growth of S. aureus more than 24 hours and S. dysenteriae up to 48 hours. This study showed the possibility of using ethyl acetate extract of Indigofera kirilowii as a material of food preservative.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.1
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• pp.51-57
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• 1992

The preservative effect of chitosan film packing on quality of lightly-salted and dried horse mackerel was studied. In preparation of chitosan film, blue crab shell chitosan was dissolved in dilute acetic acid$(1.0\%,\;v/v)$, filtered, and spreaded on plastic plate and dried at $50\pm2^{\circ}C$. The chitosan film thus obtained was neutralized with 1.0N NaOH for 2 hrs and dried at room temperature after washing several times with distilled water. The lightly-salted and dried horse mackerel product was prepared by drying for 4 hrs at $40\pm2^{\circ}C$ in hot air dryer after packing with the chitosan film. During storage at $5.0\pm0.5^{\circ}C$, moisture content of the product was higher than that of the reference, but contents of VBN(volatile basic nitrogen) , amino nitrogen, and TMA of the product on dry basis were lower than those of the reference. Viable cell count, TBA value, and peroxide value of the product were also lower than those of the reference. Judging from the result of sensory evaluation, the chitosan film packing in the storage of lightly-salted and dried horse mackerel was remarkably elongated shelf-life of the product. From the results of chemical and sensory evaluation, it was concluded that chitosan film packing was an effective method for retaining the quality of lightly-salted and dried horse mackerel.

• Journal of Korean society of Dental Hygiene
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• v.10 no.2
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• pp.311-322
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• 2010

Objectives : Since the program about sodium lauryl sulfate that might cause oral dryness and taste change including oral tissue allergy was on the air, the ingredients of D.I.Y dentifrices without sodium lauryl sulfate have been sold in online shopping mall and ordinary people can make the dentifrices easily. But there have not been any reports about the effect of dental plaque removal and preference about D.I.Y dentifrices. Therefore, this study was designed as a pilot study which aimed to investigate the effect of dental plaque removal and prefernece about D.I.Y dentifrices. Methods : 6 subjects were collected to test the effect of dental plaque removal with D.I.Y dentifrices with written consent. They didn't brushed the teeth during 12 hours until the check-up time on the next day. The O'leary index was calculated in baseline, 1 minute, 2 minute, 3 minute after brusing with D.I.Y dentifrices and market dentifrices. The preference about D.I.Y dentifrices through self-administered questionnaire was surveyed in 51 subjects after using D.I.Y dentifrices. Results : 1. The market dentifrices could remove larger amount of dental plaque than D.I.Y dentifrices, but, it wasn't significant. 2. In feeling refreshment, the market dentifrices had more positive answers significantly. 3. In feeling taste change, the market dentifries had more duration of taste change significantly. 4. In feeling oral dryness, the market dentifrices had more duration of oral dryness after toothbrushing. but, it wasn't significant. 5. As a result about reviewing the dental journals about ingredients of D.I.Y dentirices, green tea, sodium carbonate, bamboo salt, propolis had each evidence. But, We could not find out the evidences of calculus adhesion by corn starch, preservative by napri, disinfectant of peppermint. Conclusions : Although we cannot find the difference of the effect of dental plaque removal between D.I.Y dentifrices and market dentifrices, and D.I.Y dentifrices have the merits of decrease of oral dryness and taste change, it was suggested to have another test about stability and safety of D.I.Y dentifrices for safety of the user of D.I.Y dentifrices.

• Korean Journal of Food Science and Technology
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• v.39 no.1
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• pp.66-70
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• 2007

Lactobacillus fermentum YL-3 was encapsulated to increase acid tolerance and its total viability. After micro-encapsulation of L. fermentum YL-3 cells with sodium alginate and soybean oil, the morphology of the microcapsule was observed using confocal laser scanning microscopy (CLSM) after staining with pyronin Y and fluorescein isothiocyanate. The sizes of the microcapsules were 120-126 ${\mu}m$, 444-486 ${\mu}m$ and 401-463 ${\mu}m$ when manufactured at pH 2, 3 and 4, respectively. The microcapsule could hold live cells of L. fermentum YL-3 up to $1.2{\times}10^{7}$, $8.1{\times}10^{7}$ and $1.1{\times}10^{8}$ CFU/mL at pH 2, 3 and 4, respectively. The acid tolerance and preservative ability of L. fermentum YL-3 in microcapsule and macrocapsule at $4^{\circ}C$ and $25^{\circ}C$ were tested. L. fermentum YL-3 cells were evenly located in the alginate capsule matrix structure and the firmness of microcapsule was highest at pH 2. Micro-encapsulation showed the most effective acid tolerance at pH 2.0 and preservation of viability at $4^{\circ}C$. However, at $25^{\circ}C$, the macrocapsules showed more effective cell protection than the microcapsules. The application range for microcapsules could be wider than for macrocapsules in the food industry.

• Microbiology and Biotechnology Letters
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• v.35 no.1
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• pp.66-72
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• 2007

Yam has been recognized as healthy food due to its various biological activities, such as anti-obesity, antimicrobial, anticancer and immune-stimulation activities. In this study, antibacterial activities of 800 more natural plant extracts against yam-putrefactive psychrotrophic bacterium, Pseudomonas rhodesiae YAM-12, were evaluated to select a natural preservative, which is useful to long-term storage of yam and fresh-cut production. Finally, the clove oil was selected, and applied for the production of yam fresh-cut. The 1% of clove oil treated fresh-cut showed minor color changes during 31 days storage at $4^{\circ}C$ and the microbial growth was not detected. When the artificially contaminated fresh cut by dipping with P. rhodesiae YAM-12 suspension for 3 min was treated 1% clove oil, the microbial growth was identified to $10^4$ CFU/g from $10^3$ CFU/g with minor color changes. Whereas, treatment of sterilized water, or 100 ppm NaOCl into artificially contaminated fresh cut showed severe putrefaction $(10^8\;CFU/g)$ and color changes. Considering the previous reports that clove oil has antimicrobial, antioxidation, and antithrombosis activity, the use of clove oil into the yam fresh cut will provide market safety and consumer acceptability by prevention of microbial putrefaction and its biological activity.