• Journal of Food Hygiene and Safety
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• v.32 no.4
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• pp.306-313
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• 2017

This study systemically analyzed the data on the microbial levels in fresh vegetables in Korea to identify the points to control. We scanned the studies published between 2001 and 2015 in peer-reviewed research papers on the microbial levels in fresh vegetables produced in Korea. Plant products were categorized by using the US IFSAC (Interagency Food Safety Analytics Collaboration) category. The most consumed, the non-heat treated, the epidemiological foodborne diseases sources of fresh vegetable in foodservice (KCDC data) were identified by literature review. Articles were screened using National Digital Science Library (NDSL) search engine regarding to microbial hazards in plant products. Based on the total plate count number and coliforms on the 89 data cases from 26 published articles, the total plate count number was high in the order of sprouts, leaf and stem, bulbs and roots, vine-grown, solanaceous, melons, and pome. Escherichia coli was frequently detected in leaf and stem and sprouts products. Focused on the microbial data of leek, lettuce and cabbage, the levels of total plate count, coliforms and Bacillus cereus showed the levels of 4.15~7.69 log CFU/g, 1~6.99 log CFU/g, and 0.51~3.9 log CFU/g, respectively, by 33 published papers. The levels of environmental factors affecting the microbial safety of lettuce and leek before harvest were investigated. Manure, soil, hands, scale, gloves were the major potential microbial contamination points to control. In addition, GAP (good agricultural practice), microbial testing, and improvement of irrigation methods are required to provide the safer fresh produce.

• Journal of Dairy Science and Biotechnology
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• v.29 no.2
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• pp.51-57
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• 2011

Milk and dairy products are nutritionally one of the most important food in human health and the quality of raw milk is significantly important to ensure safety of dairy products. However, milk and dairy products are commonly related with chemical and microbial contaminations. Therefore, rapid and reliable detection of hazardous (e.g. pathogenic bacteria, pesticides, antibiotics, microbial toxins) in milk and dairy products is essential to ensure human health and food safety. Conventional methods for detection of food hazardous are mostly time-consuming to yield a results. Recently, biosensors have been focused as its rapidity and high sensitivity to analyse chemical and microbial hazardous from a variety of foods and environments. This study reviewed the recent trends and applications of biosensors as rapid detection method of hazardous in milk and dairy products.

• Food Science of Animal Resources
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• v.34 no.6
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• pp.792-798
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• 2014

The distribution channel of meat by-products from the pig farm to the final consumer can include a meat processor, wholesale market, wholesaler, retailer, and butcher shop. Bacterial contamination at any of these steps remains to be a serious public health concern. The aim of this study was to evaluate the distribution channel and microbial characteristics of pig by-products in Korea. Upon evaluation of pig by-products in cold storage, we found that the small and large intestine were significantly (p<0.05) higher in pH value compared to the heart and liver. The total plate counts were not significantly different among offals until cold storage for 7 d. The coliform count after 1 d of cold storage was significantly (p<0.05) higher in small and large intestine than in the other organs. The coliform count of heart, liver, and stomach showed a higher coliform count than small and large intestine until 7 d of cold storage. As determined by 16S rRNA sequencing, contamination of major pig by-products with Escherichia coli, Shigella spp., and other bacterial species occurred. Therefore, our results suggest that a more careful washing process is needed to maintain quality and hygiene and to ensure the safety of pig by-products, especially for small and large intestine.

• Korean Journal of Veterinary Service
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• v.45 no.3
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• pp.155-164
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• 2022

This study was conducted for safety evaluation on 130 pet food products, which are distributed in Gwangju, South Korea. The microbial contamination part and the usage of food additives part were mainly investigated. The five microorganisms that we tested were total viable cell counts (TVC), Coliforms, Salmonella spp., Campylobacter spp., pathogenic Escherichia coli and there were 15 products that exceed the microbial criteria or detected food poisoning bacteria. Specifically, Coliforms (13 products, 10%), TVC (9 products, 6.9%), Salmonella spp. (2 products, 1.5%), and E. coli (2 products, 1.5%) were followed. On the other hand, food additives such as preservatives, antioxidants and sodium nitrite were detected in 61 products. Among the preservatives, sorbic acid and benzoic acid were detected in 58 (44.6%) products. In antioxidants, Butylated hydroxytoluene (BHT) was detected in 3 (2.3%) products. In addition, preservatives and antioxidants were detected in 8 of 20 products labeled as 'additive-free'. Microbial contamination tended to occur mainly in small-scale individual homemade feed stores, while food additives were all detected in pet shops and supermarkets. Currently, the criteria for microorganisms and food additives for pet foods are insufficient in Korea. So, it is necessary to establish detailed feed standards and specifications for companion animals.

• Journal of Environmental Health Sciences
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• v.24 no.3
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• pp.70-76
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• 1998

Activation bacteria, identified from commercial microbial products, were applied to leachate treatment. Total seven strains of bacteria Enterobacteriaceae spp. (5), Bacillus sp. (1), Aeromonas sp. (1) were seeded in the leachate and cultured in the shaking incubator at 25$^{\circ}$C and 250 rpm. While cultured, they were sampled in given time intervals and the removal rates of SS, COD, BOD, T-N.and T-P were measured an indicators of leachate treatment. Through the screening test, four of 7 strains of bacteria were considered to be effective and they were named as "effective group". The capability of leachate treatment was observed on three different groups of bacteria single, effctive, and total mixed. The result showed that the removal rates of COD and SS for the total mixed group were 64 and 71% respectively. BOD removal rate was reached nearly 99% by seeding of effective griup and removal rates of T-P and T-N were 83 and 82% respectively. However seeding of single strain was less effective than that of any mixed group in leachate treatment.

• Korean Membrane Journal
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• v.3 no.1
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• pp.1-8
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• 2001

A lab-scale submerged membrane bio-reactor (MBR) with intermittent aeration was carried out for investigating the behavior of soluble microbial products (SMP). The SMP concentration of mixed liquor at Run 1 accumulated immediately at the end of running and biodegradable SMP converted into non-biodegradable SMP, but it did not occurred at the Run 2 and 3. The SMP formation coefficient (k) at the anoxic phase was a little higher than oxic phase, and the lowest k was investigated at Run 3. The combination of biological denitrification with the MBR Process was advantageous in the prevention of membrane bio-fouling.

• Archives of Pharmacal Research
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• v.26 no.9
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• pp.686-696
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• 2003

Ethyl (coumarin-4-oxy)acetate 1 was prepared through the reaction of 4-hydroxycoumarin with ethyl bromoacetate. Compound 1 was allowed to react with hydrazine hydrate to produce coumarin-4-oxyacetic hydrazide 2. The synthesis of N-(arylidene and alkylidene)-coumarin-4-oxyacetic hydrazones 3-20 was performed. The preparation of 2-substituted-3-[(coumarin-4-oxy) acetamido]thiazolidinones 21-26 and 2-[(coumarin-4-oxy )methyl]-4-acetyl-5-substituted-$\Delta^2$-1,3,4-oxadiazolines 27-33 was performed by the reaction of the hydrazones 3, 4, 7, 9, 12, 14 with mercaptoacetic acid and the hydrazones 3, 4, 5, 7, 12, 15, 16 with acetic anhydride, respectively. The antiviral activities, cytotoxicities and structure-activity relationship (SAR) towards different microorganisms of the prepared compounds were studied.

• Journal of Applied Biological Chemistry
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• v.58 no.3
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• pp.209-218
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• 2015

Fructooligosaccharides have been mainly produced by microbial fructosyltransferases (FTase) enzymes. The present work focuses on the optimization of medium composition and cultivation parameters affecting FTase produced by Penicillium aurantiogriseum AUMC 5605 in shake flask cultivation. FTase production was optimized in two steps using DeMeo's fractional factorial design. A 1.46-fold increase in FTase production (105.4 U/mL) was achieved using the optimized culture medium consisting of (g/L): sucrose, 600; yeast extract, 10; $K_2HPO_4$, 5; $MgSO_4{\cdot}7H_2O$, 0.5; $(NH_4)_2SO_4$, 1.0 and KCl, 0.5. The obtained results showed that the maximum FTase enzyme activity was produced at initial cultivation pH values ranging from 6.0-6.5, at agitation speed of 200 rpm and using vegetative fungal cells as inoculum. Moreover, results showed that optimization of medium composition and some cultivation parameters resulted in an increase of about 93.7% in the enzyme activity than the nonoptimized cultivation conditions after 96 h of cultivation. Additionally, maximum production and specific production rates recorded 2340 U/L/h and 102 U/L/h/g cells, respectively.

• Research in Plant Disease
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• v.19 no.4
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• pp.259-264
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• 2013

To investigate Fusarium mycotoxin contamination in rice samples from rice processing complexes (RPCs), paddy rice and rice-milling products such as husks, brown rice, blue-tinged rice, broken rice, rice bran, discolored rice, and polished rice were collected from nationwide in 2012. Three hundred seventy one samples of rice and its by-products were analyzed for three trichothethenes including nivalenol (NIV), deoxynivalenol (DON), and zearalenone (ZEA) by LC/MS. Discolored rice samples were found to have the highest contamination of DON, NIV or ZEA, followed by broken rice. Polished rice samples were largely free from mycotoxins, except three samples which were contaminated with NIV or DON at safety level. The rice byproduct samples were contaminated at higher level and frequencies than polished rice samples.

• Korean Journal of Environmental Agriculture
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• v.39 no.4
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• pp.343-351
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• 2020

BACKGROUND: Irrigation water is known to be one of the major sources of bacterial contamination in agricultural products. In addition, anti-microbial resistance (AMR) bacteria in food products possess serious threat to humans. This study was aimed at investigating the prevalence of foodborne bacteria in irrigation water and evaluating their anti-microbial susceptibility. METHODS AND RESULTS: Surface water (n = 66 sites) and groundwater (n = 40 sites) samples were collected from the Gyeongi and Gangwon provinces of South Korea during April, July, and October 2019. To evaluate the safety of water, fecal indicators (Escherichia coli) and foodborne pathogens (E. coli O157:H7, Salmonella spp., and Listeria monocytogenes) were examined. E. coli isolates from water were further tested for antimicrobial susceptibility using VITEK2 system. Overall, detection rate of foodborne pathogens in July was highest among three months. The prevalence of pathogenic E. coli (24%), Salmonella (3%), and L. monocytogenes (3%) was higher in surface water, while only one ground water site was contained with pathogenic E. coli (2.5%). Of the 343 E. coli isolates, 22.7% isolates were resistant to one or more antimicrobials (ampicillin (18.7%), trimethoprim-sulfamethoxazole (7.0%), and ciprofloxacin (6.7%)). CONCLUSION: To enhance the safety of agricultural products, it is necessary to frequently monitor the microbial quality of water.