• Journal of Food Hygiene and Safety
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• v.29 no.4
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• pp.253-259
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• 2014

This study was conducted to investigate survival of Bacillus cereus (B. cereus) on stainless steel and polyvinyl chloride (PVC) and its transfer from two material to lettuce. The stainless steel and PVC were innoculated with B. cereus and stored at 6 combination conditions (temperature : $20^{\circ}C$ and $30^{\circ}C$, relative humidity (RH) : 43%, 69%, and 100%). Although the total numbers of B. cereus at RH 43% and RH 69% were reduced by 3.53-4.00 log CFU/coupon within 24 h regardless of material type, the spore numbers of B. cereus was lasted at 3.0 log CFU/coupon. When two materials were stored at $30^{\circ}C$, RH 100%, the spore numbers of B. cereus was rapidly increased by 3.0 log CFU/coupon. In addition, the reduction rate of B. cereus was decreased in the presence of organic matter. Transfer rate of B. cereus from surface of stainless steel and PVC to lettuce was increased by 10 times in the presence of water on the lettuce surface. As a result of this study, the presence of B. cereus on produce contact surfaces can increase the risk of cross-contamination. Thus, it is important that the packing table and conveyer belt in post harvest facility should be properly washed and sanitized after working to prevent cross-contamination.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.332-336
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• 2004

An anaerobic PCE(tetrachloroethylene) dechlorinating bacterial culture from a landfill soil was enriched and characterized. The enrichment culture could dechlorinate 60$\mu$mol/$m\ell$ of PCE during a month of incubation and cis-DCE(cis-dichloroethylene) was observed as a main product of PCE dechlorination. Microbial analysis of the dechlorinating enrichment culture by rising PCR-DGGE (Polymerase chain reaction-Denaturing gradient gel electrophoresis) method showed that at least three microorganisms were related to the anaerobic PCE dechlorination.

• Natural Product Sciences
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• v.9 no.4
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• pp.220-222
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• 2003

Two new abietane diterpenes with rearranged skeleton; aegyptinol and aegyptinone C; have been isolated and identified for the first time from the anti-microbial petroleum ether extract of the roots of Salvia aegyptiaca L. Their chemical structures have been elucidated by interpretation of the detailed 1D-and 2D-NMR spectra, as well as other spectroscopic tools. In addition, full assignment of $^{13}C-NMR$ of aegyptinone B was also conducted for the first time.

• Journal of Microbiology and Biotechnology
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• v.2 no.1
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• pp.41-45
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• 1992

Shikonin production was examined in a bubble column bioreactor system with the hairy roots of Lithosphermum erythrorhizon. The volumetric productivity was higher than those obtained from other reactor configurations with free or immobilized cells of the same cell line. The productivities of the bubble column reactor, with and without a product absorption trap, were 7.4 and 4.5 mg of shikonin/l/d, respectively. This indicated the importance of the product removal in the design and operation of the shikonin production system with hairy root culture.

• Journal of Dairy Science and Biotechnology
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• v.36 no.1
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• pp.26-31
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• 2018

Tarak is a traditional Korean fermented milk product, which is prepared by the addition of rice wine to milk. The major microbial strains found in Tarak are Leuconostoc citreum, Lactobacillus plantarum, Lactococcus lactis, Saccharomyces cerevisiae, and Pichia kudriavzevii. The activity of lactic acid bacteria isolated from traditional Korean foods of Taraki against the carcinogenic bacteria Helicobacter pylori, Escherichia coli O157:H7, and Cronobacter sakazakii was characterized. Tarak extract significantly increased the proliferation of T-lymphocyte Jurkat (clone E6-1) cells. Tarak also inhibited the tyrosinase activity and melanin biosynthesis induced by an ${\alpha}$-melanocyte-stimulating hormone in pituitary intermediate lobe.

• Food Science and Industry
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• v.50 no.2
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• pp.27-36
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• 2017

Today, the food packaging industry has a great interest in using active packaging to fresh food product as a solution for the future to positively provide its quality, safety and shelf life. Many researches have extensively studied functional packaging strategies in recently years. Controlled release packaging (CRP) is an innovative packaging technology in the packaging polymer matrix from which can active agents are delivered in a controlled way into the product. CRP technology is well-suited for controlling release of antimicrobial compounds and antioxidants to prevent food degradation reactions such as microbial growth and lipid oxidation. Advances in CRP technology allow food packaging manufacturers to challenge the development of better functional food packaging systems. This overview examines the most recent developments and technologies of active packaging for applying the food industry. The scope of this article has mainly been focused on controlled releasing systems.

• The Korean Journal of Pesticide Science
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• v.10 no.1
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• pp.56-65
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• 2006

An antagonistic bacterial isolate, that inhibits the growth of plant pathogens, was selected and identified from 5,000 isolates screened from the rhizosphere of various crop plants. An isolate Bacillus sp. N32, tested against Colletotrichum gloeosporioides causing anthracnose disease in hot pepper, produced both a heat resistant antifungal protein and a heat sensitive antifungal protein. The heat resistant protein was partially purified by Ammonium sulfate fractionation and gel filtration chromatography. The bioautography showed that the proteins possessed high antifungal activity. The biosynthetic gene cluster responsible for the heat resistant antifungal protein was cloned from cosmid library using DNA probe obtained from PCR product with the primers targeting the conserved nucleotide sequence of the synthetic genes reported earlier, Most of the clones obtained showed higher homology to fengycin antibiotic synthetic gene family reported earlier. On the other hand, the heat sensitive protein was isolated from SDS-PAGE and electroblotting to determine the N-terminal amino acid sequences. The heat sensitive antifungal protein gene was cloned from the ${\lambda}-ZAP$ libraries using a DNA probe based on the N-terminal amino acid sequences of the heat sensitive protein. We are contemplating to clone and sequence the whole gene cluster encoding the heat sensitive protein for further analysis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.5
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• pp.612-617
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• 2009

Fresh vegetable juice is a non-heat treated product and the only step to reduce microbial growth is washing. Therefore, the materials for fresh vegetable juice including Angelica keiskei, Brassica loeracea var. acephala, and Daucus carota L. were treated by ozone after the first washing process and investigated for microbial and chemical changes. The number of the total aerobic bacteria in materials after selection step were $8.2{\times}10^5{\sim}5.0{\times}10^6\;CFU/g$, which was a higher contamination level than the limit of Korea food code ($10^5\;CFU/g$). However, after the 1st washing process and ozone treatment, the total aerobic bacterial number was reduced to $4.7{\times}10^4{\sim}6.7{\times}10^4\;CFU/g$, which showed 2 log microbial reduction. After the 2nd washing step followed by ozone treatment, there was no difference in microbial number. The number of colifroms in the materials of fresh vegetable juice were $8.0{\times}10^3{\sim}3.5{\times}10^3\;CFU/g$ initially but showed $1.5{\times}10^2{\sim}3.0{\times}10^2\;CFU/g$ after the ozone treatment (1 log reduction). On the other hand, there was no changes in the contents of ascorbic acid, flavonoids, polyphenols, minerals (cadmium and lead) during all processes. In addition, no color changes were observed during washing process. Therefore, ozone treatment in the materials of fresh vegetable juice decreased the microbial numbers. Also, chemical characteristics of ozone treated sample were not different when compared with control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.7
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• pp.1109-1114
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• 2013

Microbial community analysis was performed on Tarak, a traditional Korean fermented milk product, by 16S rDNA cloning and pyrosequencing to obtain basic data for the standardization and systematization of the Tarak manufacturing process. Microbial analysis of the prokaryotic community revealed a slight difference in microbial abundance between Bontarak (n) and Tarak (n+1), but Firmicute was dominant at the phylum level. At the genus level, the Lactobacillus and Leuconostoc genera constituted over 90% of the population in Bontarak, but Lactococcus was the dominant genus in Tarak. Bontarak and Tarak showed further differences at the species level. Leuconostoc citreum was the dominant species in Bontarak, constituting 40% of the population. In eukaryotic community analysis, all samples were composed of Ascomycota at the phylum level. At the genus level, Saccharomyces was dominant in Bontarak (85% of the population), while Issatchenkia was dominant in Tarak (95% of the population). At the species level, Saccharomyces cerevisiae was detected at a relative abundance in Bontarak (82%), and Pichia kudriavzevii was the dominant species in Tarak, with a relative abundance of 95%. Sensory evaluation indicated that Tarak had a better appearance and texture than Bontarak. As sweetness was not significantly different between the two samples just slightly higher in Tarak, this was likely due to a significant decrease in sourness in Tarak. These results suggest that the microbial community used affects the quality of Tarak produced. Thus, a stable microbial community must be maintained for the production of Tarak with consistent quality.

• Journal of Soil and Groundwater Environment
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• v.17 no.3
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• pp.32-38
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• 2012

This study was conducted to evaluate the slurping process affecting the variation of free product and VOCs concentration and the bioaugmentation effect on bioremediation process. Free products and soil gas were extracted from 30 extraction wells installed in a petroleum contaminated area. The extraction system was operated for 10 hours per day with 1 hour on-and-off mode. The thickness of free product in extraction well was decreased from 11.7 cm to 4.5 cm and the VOCs concentration was increased from 10.37 ppm to 30.78 ppm during the operation period. After the slurping process for 2 months, contaminated soil was treated with bioremediation process in 2 cells, $15{\times}40$ m, biologically enhanced with adjusting oxygen, moisture and nutrients concentration. Total 1,400 L of microbial inoculant, Naturesys. (Dong Myung Ent. Co.) was added to the pile B, which has an outstanding ability for degrading petroleum hydrocarbons. The results showed that bioremediaton effect in soil with the microorganisms solution is 33% higher than that in soil with only residual bacteria.