• Journal of Microbiology and Biotechnology
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• 제10권2호
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• pp.227-232
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• 2000

Fresh pine needles were collected and extracted with 95% methanol and the extract was concentrated to determine its antimicrobial activity. The methanol extract had a considerable inhibitory effect on the tested bacteria, such as Esherichia coli 0157;H7, Listeria monocytogenes, Salmonella typhimurium, and Staphylococcus aureus. The methanol extract of pine needles was further fractionated to chloroform, ethylacetate, butanal, and water fractions. Among these four fractions, the butanol and water fractions, which showed a relatively strong inhibitory effect on all of the tested bacteria, were purified and the minimum ingibitory concentration (MIC) was determined for each microorganism. The MIC raged between 25 mg/ml and 45 mg/ml depending on the microorganism. the purified active fractions were applied to sterilized milk as a model food system to define the antimicrobial effectiveness and it was found that the antimicrobial activities in the water fractions were stronger than those in the butanol fractions.

• 한국식품위생안전성학회지
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• 제37권3호
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• pp.121-128
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• 2022

The rapid development of biotechnology has increased the importance of microorganisms or their genetic information. Thus, the Nagoya Protocol on access to genetic resources and the fair and equitable sharing of benefits arising from their utilization was established, and countries are working to secure industrially and academically useful bioresources to deal with the agreement. In the case of Korea, because 67% of bioresources are imported from abroad, we are required to secure domestic bioresources as well. The number of isolated foodborne illness-causing microorganisms is predicted to invrease based on the incresing number of outbreaks of foodborne illness each year. Consequently, appropriate long-term preservation methods are necessary to secure the isolated microorganisms for the purpose of research and resourcification. Therefore, the long-term preservation methods for bacteria, fungi, viruses, and protozoa were investigated in this study, from domestic and international bioresource banks, and the functions of the cryoprotectants were reviewed and discussed. This review should be informative in the preservation of microorganisms and contribute to the development of biotechnology.

• 한국식품조리과학회지
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• 제32권4호
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• pp.476-491
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• 2016

Purpose: This study investigated consumers' perception of food safety and risk from foodborne illness and consumption pattern of meat and processed meat products in Korea. Methods: A quantitative survey was performed by trained interviewers, surveying 1,500 adults who were randomly selected from six major provinces in Korea. Results: Most of the respondents reported foodborne illness risk related to the consumption of raw meat but not related to heated meat and processed meat products. As respondents perceived the risk of food poisoning from raw meat, the purchase and intake decreased (p<0.001). Most of the respondents considered a low possibility of foodborne illness at home. Seventy-seven percent of the respondents thought that bacteria and virus are the main causes of foodborne illness. Improper storage practice (40.7%) and unsafe food material (29.3%) were the main risk factors contributing to foodborne illness. Perception and practice of food safety was significantly different by the residency area. The most preferred meat, processed meat, and processed ground meat products were pork (58%), ham (31.1%), and pork cutlet (40.4%), respectively. The most preferred cooking method was roasting, regardless of the type of meat, but the second preference for cooking method was significantly affected by the type of meat (p<0.001): stir-fried pork, beef with seasoning, fried-chicken and boiled duck. Frequency of eating out was 0.75/day on weekdays and 0.78/day on weekends at the mainly Korean BBQ restaurant. Conclusion: The results of this study could be used to develop science-based education materials for consumer and the specific guideline of risk management of meat and processed meat products.

• Journal of Microbiology and Biotechnology
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• 제28권2호
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• pp.227-235
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• 2018

Foodborne illness represents a major threat to public health and is frequently attributed to pathogenic microorganisms on fresh produce. Recurrent outbreaks often come from vegetables that are grown close to or within the ground. Therefore, the first step to understanding the public health risk of microorganisms on fresh vegetables is to identify and describe microbial communities. We investigated the phyllospheres on Chinese cabbage (Brassica rapa subsp. pekinensis, N = 54). 16S rRNA gene amplicon sequencing targeting the V5-V6 region of 16S rRNA genes was conducted by employing the Illumina MiSeq system. Sequence quality was assessed, and phylogenetic assessments were performed using the RDP classifier implemented in QIIME with a bootstrap cutoff of 80%. Principal coordinate analysis was performed using a weighted Fast UniFrac matrix. The average number of sequence reads generated per sample was 34,584. At the phylum level, bacterial communities were composed primarily of Proteobacteria and Bacteroidetes. The most abundant genera on Chinese cabbages were Chryseobacterium, Aurantimonadaceae_g, Sphingomonas, and Pseudomonas. Diverse potential pathogens, such as Pantoea, Erwinia, Klebsiella, Yersinia, Bacillus, Staphylococcus, Salmonella, and Clostridium were also detected from the samples. Although further epidemiological studies will be required to determine whether the detected potential pathogens are associated with foodborne illness, our results imply that a metagenomic approach can be used to detect pathogenic bacteria on fresh vegetables.

• Fisheries and Aquatic Sciences
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• 제25권9호
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• pp.463-472
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• 2022

In this study, a microbial risk assessment was performed for the bacteria Vibrio parahaemolyticus, which causes a foodborne illness following the consumption of Jeotgal, a fermented seafood in South Korea. The assessment comprised of six stages: product, market, home, consumption, dose-response, and risk. The initial contamination level (IC) was calculated based on the prevalence of V. parahaemolyticus in 90 Jeotgal samples. The kinetic behavior of V. parahaemolyticus was described using predictive models. The data on transportation conditions from manufacturer to market and home were collected through personal communication and from previous studies. Data for the Jeotgal consumption status were obtained, and an appropriate probability distribution was established. The simulation models responding to the scenario were analyzed using the @RISK program. The IC of V. parahaemolyticus was estimated using beta distribution [Beta (1, 91)]. The cell counts during transportation were estimated using Weibull and polynomial models [δ = 1 / (0.0718 - 0.0097 × T + 0.0005 × T²)], while the probability distributions for time and temperature were estimated using Pert, Weibull, Uniform, and LogLogistic distributions. Daily average consumption amounts were assessed using the Pareto distribution [0.60284,1.32,Risk Truncate(0,155)]. The results indicated that the risk of V. parahaemolyticus infection through Jeotgal consumption is low in South Korea.

• 동아시아식생활학회지
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• 제22권5호
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• pp.692-700
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• 2012

The antibacterial activity of the ethanol extract of Cornus officinalis against some bacteria related to foodborne illness and food spoilage was investigated. In the case of the disc diffusion assay, clear zones due to the inhibition of proliferation by Cornus officinalis extract were 8.5~18.3 mm at $4,000{\mu}g/disc$. The inhibitory effect of Cornus officinalis was as follows: Escherichia. coli ${\geq}$ Listeria monocytogenes ${\geq}$ E. coli O157:H7 > Bacillus cereus > Staphylococcus aureus > Pseudomonas aeruginosa > Salmonella typhimurium. In addition, the MIC of Cornus officinalis extract toward B. cereus was the lowest at 1,000 ppm. The extract inhibited the growth of E. coli, L. monocytogenes, E. coli O157:H7, and Bacillus cereus throughout the growth stage. However, the growth of P. aeruginosa, S. aureus, and S. typhimurium was only inhibited by the extract during the lag phase. The constituents of all cells tested were released, especially E. coli and E. coli O157:H7. Observation of the cells using SEM demonstrated a morphological change and disruption of cells in response to treatment with Cornus officinalis extract. Based on these findings, the ethanol extracts of Cornus officinalis showed strong antimicrobial activity against all tested bacteria, indicating that Cornus officinalis can be a useful natural antimicrobial reagent.

• 한국축산식품학회지
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• 제32권2호
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• pp.241-246
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• 2012

This report outlines the development of a rapid, simple, and sensitive detection system for pathogenic bacteria using a capillary electrophoresis-based, single strand conformation polymorphism (CE-SSCP) combined with PCR. We demonstrate that this method, used with primers targeting the V4 region of the16S rRNA gene, is capable of the simultaneous detection of 10 microbes that could be associated with foodborne illness, caused by animal-derived foods: Salmonella enterica, Listeria monocytogenes, Escherichia coli O157:H7, Campylobacter jejuni, Staphylococcus aureus, Bacillus cereus, Clostridium perfringens, Yersinia enterocolitica, Vibrio parahaemolyticus, and Enterobacter sakazakii. The traditional detection techniques are time-consuming and labor-intensive, due to the necessary task of separate cultivation of each target species. As such, the CE-SSCP-PCR method, that we have developed, has the potential to diagnose pathogens rapidly, unlike the traditional technique, in order to prevent foodborne illness in a much more efficient manner.

• 한국식품조리과학회지
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• 제28권1호
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• pp.9-15
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• 2012

This study analyzed the antibacterial activity of a Rubus coreanum (Bokbunja) ethanol extract. The antimicrobial activity was determined by disc diffusion, minimum inhibitory concentration (MIC), and growth inhibition methods with seven kinds of bacteria related to foodborne illness (Bacillus cereus, Escherichia coli, Escherichia coli O157:H7, Listeria monocytogenes, Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella typhimurium). In the results, disc diffusions of the ethanol extract from R. coreanum (9.8-17.5 mm at $4,000{\mu}g/disc$) clearly showed the antimicrobial activity of the extract against all tested microorganisms. Rubus coreanum promoted an inhibitory effect as follows: E. coli O157:H7 > P. aeruginosa > L. monocytogenes > E. coli > S. aureus > B. cereus ${\geq}$ S. typhimurium. In the MIC test, R. coreanum showed high antimicrobial effect against L. monocytogenes at 500 ppm. Moreover, the R. coreanum ethanol extract showed strong growth inhibition against microorganisms, similar to the MIC results. These results show that a R. coreanum ethanol extract has powerful antimicrobial activity against all tested microorganisms, suggesting that R. coreanum will be useful as a potential natural preservative.

• Journal of Biosystems Engineering
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• 제31권2호
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• pp.128-134
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• 2006

Frequent outbreaks of foodborne illness demand the need for rapid and sensitive methods for detection of these pathogens. Recent development of biosensor technology has a great potential to meet the need for rapid and sensitive pathogens detection from foods. An antibody-based fiber-optic biosensor and an automated reagents supply system to detect Listeria monocytogenes were developed. The biosensor for detection of Listeria monocytogenes in PBS and bacteria spiked food samples was evaluated. The automated reagents supply system eliminated cumbersome sample and detection antibody injection procedures that had been done manually. The biosensor could detect $10^4$ cfu/ml of Listeria monocytogenes in PBS. By using the fiber-optic biosensor, $2x10^8$ cfu/ml of Listeria monocytogenes in the food samples were detectable.

• Journal of Microbiology and Biotechnology
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• 제28권4호
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• pp.551-560
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• 2018

Bellflower root (Platycodon grandiflorum), which belongs to the Campanulaceae family, is a perennial grass that grows naturally in Korea, northeastern China, and Japan. Bellflower is widely consumed as both food and medicine owing to its high nutritional value and potential therapeutic effects. Since foodborne disease outbreaks often come from vegetables, understanding the public health risk of microorganisms on fresh vegetables is pivotal to predict and prevent foodborne disease outbreaks. We investigated the microbial communities on the bellflower root (n = 10). 16S rRNA gene amplicon sequencing targeting the V6-V9 regions of 16S rRNA genes was conducted via the 454-Titanium platform. The sequence quality was checked and phylogenetic assessments were performed using the RDP classifier implemented in QIIME with a bootstrap cutoff of 80%. Principal coordinate analysis was performed using the weighted Fast UniFrac distance. The average number of sequence reads generated per sample was 67,192 sequences. At the phylum level, bacterial communities from the bellflower root were composed primarily of Proteobacteria, Firmicutes, and Actinobacteria in March and September samples. Genera Serratia, Pseudomonas, and Pantoea comprised more than 54% of the total bellflower root bacteria. Principal coordinate analysis plots demonstrated that the microbial community of bellflower root in March samples was different from those in September samples. Potential pathogenic genera, such as Pantoea, were detected in bellflower root samples. Even though further studies will be required to determine if these species are associated with foodborne illness, our results indicate that the 16S rRNA gene-based sequencing approach can be used to detect pathogenic bacteria on fresh vegetables.