• Applied Biological Chemistry
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• v.12
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• pp.57-67
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• 1969

1) Many bacterial strains identified as Bacillus megeterium, Bacillus subtilis and Bacillus licheniformis were aboundantly found in summer jokal kimchi, but the most dominant strains in summer kimchi were Lactobacillus plantarum and Loctobacllus buchneri. 2) Bacillus groups found in kimchi were sensitive in a low concentration of AF-2, but groups of lactic acid bacteria were resistant to a high concentration of AF-2. 3) Allowable concentration of AF-2 in Korean kimchi is less than 10 p.p.m. 4) AF-2 was not suitable for the juicy kimchi as a preservative because the color of juicy kimchi was somewhat changed into orange red when 10 p.p.m. of AF-2 was added. 5) High concentration of AF-2 leads the hetero-fermentation of kimchi bacteria to the homofermentation. 6) Microflora of kimchi was influenced even in the concentration of 10 p.p.m. but it was impossible to check the acidification of kimchi in summer with 50 p.p.m. concentration of AF-2. 7) About 25% of AF-2 was consumed in kimchi fermentation for day at $23^{\circ}-25^{\circ}C$.

• Journal of the Korean Wood Science and Technology
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• v.38 no.6
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• pp.532-540
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• 2010

The strength properties of wooden model retaining wall made of pitch pine (Pinus rigida Miller) was evaluated. Three different types of wooden model retaining wall were made of the 11cm square timber treated with CUAZ-2 (Copper Azole). The retaining wall was made into the 4 layers of crossbar and the 3 layers of vertical-bar, of which the size was 86 cm high, 200 cm long and 96 cm wide. Type I was control and in Type II 20 cm vertical-bars and 93 cm vertical-bars were arranged alternately to decrease wood usage. TypeIII was similar to TypeII except that the connection between crossbars was reinforced with the wooden armature. In each type, the strength properties of retaining wall were investigated by horizontal loading test and the deformation of structure by image processing (AICON 3D DPA-PRO system). In horizontal loading test of Type I, Type II and Type III was 63.17, 57.80, and 60.97 kN/m, respectively. The deformation of the top layer in Type II was 1.5 times larger than in Type I and Type III. Consequently, the economic efficiency and strength performance were better in Type III than in Type I and Type II.

• Journal of the Korean Wood Science and Technology
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• v.48 no.4
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• pp.513-526
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• 2020

The existing preservation methods are difficult to be applied to a large dimension log which is needed for making traditional wooden ship 'Jalur' in Riau Province. Novel techniques to provide the use of readily available species to replace traditional species alternative were investigated. These included infusion and a combination of injection and bandage-wrapping methods for preserving living trees of Balam (Macaranga conifera (Rchb.f. & Zoll.) Müll.Arg.) and Bintangor (Calophyllum soulattri Burm.f.). Water-based boron compounds were applied as wood preservatives. In total, 18 discs from the bottom, middle, and top of four trees and two controls were used. Trees undergoing treatment were also used to see how wood anatomical structure might affect the boron penetration. The overall aim was to identify the best method for use in Jalur manufacturing. The results showed that in infused Balam tree where the hose position for the preservative intake was deep (10-15 cm from the bark), no boron compound was observed in the outer sapwood. Combination of injection and bandage-wrapping method gave higher percentage of boron penetration at bottom and middle of Balam tree. However, infused Bintangor showed 100% boron penetration. The larger vessel diameter, the absence of tyloses, and the simple perforation plates in Bintangor wood were likely to have contributed to the higher penetration of boron. The combination of bandage-wrapping and infusion, or alternatively by infusing the living trees close to the bark, and at as low as position in the stem gives better protection when treatments are applied to living trees.

• Applied Biological Chemistry
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• v.49 no.2
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• pp.108-113
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• 2006

This study was conducted to analyze the acidity and turbidity changes of immersion solutions as well as changes in aerobic bacteria, E. coli, anaerobic bacteria, yeast and mold counts of mulberry leaf soybean curds during storages at $4^{\circ}C$ and $25^{\circ}C$ in different immersion solutions such as distilled water, grapefruit seed extract (300 ppm) and alkaline ionic water. The acidities of immersion solutions of distilled water, grapefruit seed extract and alkaline ionic water after 18 days of storage at $4^{\circ}C$ were 0.021, 0.008 and 0.002%, respectively. After 5 days of storage at $25^{\circ}C$ were 0.042, 0.029 and 0.009%, respectively. The turbidities of the above mentioned immersion solutions were 0.50, 0.29 and 0.21 after 18 days of storage at $4^{\circ}C$ and 0.38, 0.34 and 0.27, respectively, after 5 days of storage at $25^{\circ}C$. The acidity and turbidity changes of immersion solutions were sensitive to storage temperatures. The aerobic bacteria count of mulberry leaf soybean curds after 18 days of storage at $4^{\circ}C$ was still below $10^7\;CFU/g$, the beginning point of soybean curd putrefaction; in contrast, this value was reached within one day in distilled water at $25^{\circ}C$ and between 2 and 3 days in alkaline ionic water. Grapefruit seed extract and alkaline ionic water had a better preservative effect at $4^{\circ}C$ than at $25^{\circ}C$ storage temperature.

• Journal of Food Hygiene and Safety
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• v.24 no.2
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• pp.143-147
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• 2009

A survey of food preservatives, sulfur dioxide and microbial contamination levels was conducted on 73 seasoned dried fishes(41 squids, 17 filleted fish, 6 Alaska pollack, 9 others) collected from domestic markets and internet. Among preservatives, only sorbic acid was detected in 25 samples including 23 seasoned dried squids, 1 seasoned filleted fish and 1 seasoned dried Alaska pollack with a range $0.01{\sim}0.92g/kg$. Sulfur dioxide was detected from one sample(seasoned dried squid) and its content was 10.5 mg/kg. All samples were contaminated by total aerobic bacteria, and the degree was $3.00{\sim}6.45\;log_{10}$ CFU/g(average level was $5.09\;log_{10}$ CFU/g). Escherichia coli, Salmonella spp. and Staphylococcus aureus were not detected in all samples. On the basis of the results above, most of the seasoned dried fishes were appropriate for Korea food standard, yet biological hygiene control will be needed constantly.

• The Journal of the Korean Society for Microbiology
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• v.21 no.4
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• pp.435-439
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• 1986

The viability of tubercle bacilli in the sputum specimens has been investigated after different periods of storage at diffeent temperatures and in the presence of different preservatives. No loss of culture positives was observed for one week storage at $4^{\circ}C$, but 9.8% 19.5%C, and 26.8% of sputums failed to yield positives on 2, 3, and 4 weeks of storage respectively. At $25^{\circ}C$ even one week storage made 19.5% of sputums fail to yield positive culture and 2, 3, and 4 weeks of storage made 36.6% 70.7%, and 90.2% of sputums fail to yield positive culture respectively. And contamination was unacceptably high beyond one week of storage at $25^{\circ}C$. Contamination of sputum specimens could be protected fairly well by 0.5% boric acid, by 5% trisodium phosphate or by 0.5% cetylpyridium chloride, but, except CP, the former two had no advantage at all to protect viability of tubercle bacilli over the specimens without preservative. The CP was much less harmful to the viability of tubercle bacilli than BA, yielding 61.0% and 31.7% of culture positives on 3 and 4 weeks of storage in the presence of CP, while BA yielded 34.1% and 4.9% of positives on the same respective periods of storage. Therefore CP may be useful to preserve sputums if it takes more than 2 weeks to transport them at the temperature of over $25^{\circ}C$.

• The Korean Journal of Food And Nutrition
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• v.23 no.2
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• pp.154-161
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• 2010

The aim of this study was to investigate antibacterial activities of essential oil from C. morifolium against four Grampositive bacteria and six Gram-negative bacteria. The antibacterial activity of the oils was determined by agar-well diffusion assay, minimum inhibitory concentration(MIC), and minimum bactericidal concentration(MBC). Essential oil of C. morifolium had a large inhibition zones especially against Salmonella enterica(21 mm) and Bacillus cereus(19 mm). Essential oil of C. morifolium generally showed higher antibacterial activity against Gram-positive bacteria than Gram-negative bacteria. MIC of essential oil from C. morifolium was 5 ${\mu}g/m{\ell}$ against ten food-borne pathogens. MBC values were determined to be from 5 to 20 ${\mu}g/m{\ell}$ against eight bacteria except Salmonella choleraesuis and Listeria monocytogenes. Therefore, the essential oil of C. morifolium and its components have a potent antibacterial activity against food-borne pathogens, and is expected to be used as a novel food preservative.

• Journal of Life Science
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• v.20 no.6
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• pp.934-939
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• 2010

We have previously reported recombinant productions of bacteriocins using yeast expression plasmid pAUR123, which contains the alcohol dehydrogenase (ADH) promoter, in Saccharomyces cerevisiae cells and their antibacterial activities. In order to improve the antibacterial activities of bacteriocidal yeast cells, a strong glyceraldehyde phosphate dehydrogenase (GPD) promoter gene of S. cerevisiae was amplified and inserted upstream into bacteriocin genes such as the OR-7, Subpeptin JM4-A or JM4-B gene in the corresponding recombinant yeast plasmid. Yeast cells transformed by the recombinant plasmid containing the GPD promoter represented higher antibacterial activities against both Gram positive B. subtilis and Gram negative E. coli cells compared to those transformed by the corresponding recombinant plasmid containing the ADH promoter. Thus, yeast cells harboring the recombinant plasmid containing the GPD promoter constructed in this study could be applied in the food preservative or animal feed industries.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.4
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• pp.126-137
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• 2014

Characteristics of heating and drying of Canadian-imported Douglas-fir timber using microwave in order to secure convenience and quality of drying timber and to get basic data for secondary conservation treatment are as follows: As the results of analysis of change curves of internal temperature of the timber after irradiating it, round timber and board timber showed stable heat distribution, heat consumption and surface water-content in heating with 30kW for 30 minutes and 120 minutes and with 40kW for 3 minutes and 9 minutes, respectively. Especially, surface water-content distribution according to heating by microwave showed very even leveling and water-content decrease rate was also more 30% compared to its weight showing excellent dry efficiency. And in case of soaking timbers into liquid chemicals for secondary conservation according to the analysis results of heat consumption, it is expected that large amount of preservative will be permeated. Therefore, timber heated by microwave is remarkably available for using industrial materials and developing secondary utilized products with its fast water-content decrease and dryness and higher heat consumption.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.458-464
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• 1999

The value of lysozyme as a natural food preservative is continuously increased due to its unique antimicrobial activity. To determine the optimum separation concentration among the various hen egg white protein (HEWP) concentrations (0.25, 0.5, 1.0, w/v), protein concentrations, lysozyme concentrations, specific activities (SA), and purification factors of prefiltered solution (PFS) and PM30 permeate solution (PMS) were compared. The purity of lysozyme separated at each step was analyzed and confirmed by gel permeation chromatography and electrophoresis. The fouling deposits on membrane were observed by SEM. The non-enzymatic proteins were removed over 99% by ultrafiltration (UF). The increased feed concentration did not contribute to the increase of SA. SA of PMS was 18 to 31 times higher than that of PFS. The optimum feed concentration was decided as 0.25% based on SA and purification factor. The non-enzymatic region of gel chromatogram was proved to be ovalbumin. The thickness of deposit on the UF membrane was approximately $0.9{\mu}m$ and removed by cleaning with 0.1 N NaOH. Therefore, UF using PM30 membrane was very effective to separate the antimicrobial lysozyme from various HEWPs.