• Korean Journal of Soil Science and Fertilizer
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• v.17 no.1
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• pp.67-76
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• 1984

This experiment was conducted to find out the changes in microflora of submerged soil uncultivated rice plant by application of CNP herbicide (2, 4, 6 - Trichlorophenyl-4-Nitrophenyl ether) under conditions applied with compost, rice straw, glucose or without organic material. The soil, sandy loam textured was incubated in green house for 66 days. Sampling and analysis of microorganisms were carried out during submergence periods. The results were summarilized as follows. 1. Number of aerobic total bacteria was increased by application of CNP herbicide during submerbed 50 days, afterthen, could not seen the difference. The application of rice straw increased number of aerobic bacteria regardless of CNP herbicide application or not, but glucose tended to decrease. 2. Number of Fungi was constantly maintained at $8-20{\times}10^3$ levels during period of submergence regardless of application of CNP herbicide and organic materials or not. 3. The CNP herbicide application tended to decrease the number of actinomycetes, particularly, in the treatments without organic substances and rice straw were remarkably decreased. 4. Anaerobic-and gram-negative bacteria populations were not showed any difference by application of herbicide and organic materials. 5. The ratios of aerobic bacteria to fungi and aerobic bacteria to actinomycetes appeared high values by application of herbicide and of organic substances. 6. At 66 days after submergence, the ratio of chromogenic actinomycetes to the total number of actinomycetes was lowered in application of herbicide. On the other hand, the percentage of both pretense-positive and cellulase-positive actinomycetes to the total isolates were higher in the treatment with herbicide than An without herbicide, particularly. The ratios of pretense-positive actinomycetes were high in the rice straw application regardless of herbicide application or not, but cellulase-positive actinomycetes was not remarkably difference.

• Journal of Environmental Health Sciences
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• v.32 no.1 s.88
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• pp.77-88
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• 2006

This study were conducted to investigate the microbial contamination level in 5 tomato farms in Western Gyeongnam. A total of 130 samples was examined for sanitary indicator bacteria, such as aerobic plate count (APC), coliforms, and Escherchia coli, and pathogenic bacteria such as E. coli O157:H7, Salmonella spp., Staphylococcus aureus, and Listeria monocytogenes. APC and coliform count ranged $0\~6.62\;and\;0\~4.52 log_{10}\;CFU/(ml,\;g,\;100\;cm^2,\;hand)$, respectively, and $32.5\%$ were contaminated with E. coli. Especially, most of the samples from employees are high as above $4.0\;log_{10}\;CFU/(ml,\;g,\;100\;cm^2,\;hand)$ in APC. S. aureus, detected at $10.7\%$, was found in employees' hands, irrigation water, and hydroponic solution. whereas E. coli $O157:H7$, Salmonella spp, and L. monocytogenes were not detected. These results will provide fundamental microbiological information for introduction of good agricultural practice (GAP)system in tomato farms.

• Preventive Nutrition and Food Science
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• v.13 no.1
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• pp.45-50
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• 2008

The effect of aqueous chlorine dioxide ($ClO_2$) treatment on microbial growth and quality of chicken leg during storage was examined. Chicken leg samples were treated with 0, 50, and 100 ppm of $ClO_2$ solution and stored at $4^{\circ}C$. Aqueous $ClO_2$ treatment significantly decreased the populations of total aerobic bacteria, yeast and mold, and coliforms in chicken leg. One hundred ppm $ClO_2$ treatment reduced the initial populations of total aerobic bacteria, yeast and mold, and coliforms by 0.93, 1.15, and 0.94 log CFU/g, respectively. The pH and volatile basic nitrogen values in the chicken leg decreased with increasing aqueous $ClO_2$ concentration, while concentrations thiobarbituric acid reactive substances (TBARS) increased during storage regardless of aqueous $ClO_2$ concentration. Sensory evaluation results revealed that the quality of the chicken leg treated with aqueous $ClO_2$ during storage was better than that of the control. These results indicate that aqueous $ClO_2$ treatment can be useful for improving the microbial safety of chicken leg during storage.

• Food Science and Preservation
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• v.16 no.3
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• pp.454-458
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• 2009

The effect of UV-C irradiation on microbial growth and quality of red pepper powder during storage was examined. Red pepper powder was irradiated with doses of 27, 54, or $108\;kJ/m^2$ and stored at $20^{\circ}C$ for 4 weeks. UV-C treatment of red pepper powder decreased the populations of total aerobic bacteria and Bacillus cereus in proportion to radiation dose. In particular, total aerobic bacteria and B. cereus populations decreased by 1.03 and 0.90 log CFU/g after irradiation at $108\;kJ/m^2$, respectively, compared with control values. UV-C irradiation caused negligible changes in the Hunter color L, a, or b values. Sensory quality results on red pepper powder were not significantly different between treatments. Therefore, UV-C irradiation can be used to inhibit microbial growth in red pepper powder, without impairing quality during storage.

• Food Science of Animal Resources
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• v.32 no.5
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• pp.561-570
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• 2012

The objective of this study was to evaluate the effects of an atmospheric pressure plasma (APP) jet on L. monocytogenes inactivation, quality characteristics, and genotoxicological safety of cooked egg white and yolk. APP treatment using He gas resulted in a 5 decimal reduction in the number of L. monocytogenes in cooked egg white, whereas that using $He+O_2$, $N_2$, and $N_2+O_2$ decreased the number further, and to undetectable levels. All treatments of cooked egg yolk resulted in undetectable levels of inoculated L. monocytogenes. There were no viable cells of total aerobic bacteria after APP treatment on day 0 while the control showed approximately 3-4 Log CFU/g. On day 7, the numbers of total aerobic bacteria had increased by approximately 3 log cycles in cooked egg white, but there were no viable cells in cooked egg yolk after 2 min of APP jet. APP treatment decreased the $L^*$-values of cooked egg white and yolk significantly on day 0. No significant sensory differences were found among the cooked egg white samples, whereas significant reductions in flavor, taste, and overall acceptability were found in cooked egg yolks treated with APP jets. SOS chromotest did not reveal the presence of genotoxic products following APP treatments of cooked egg white and yolk. Therefore, it can be concluded that APP jets can be used as a non-thermal means to enhance the safety and extend the shelf-life of cooked egg white and yolk.

• Food Science of Animal Resources
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• v.36 no.2
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• pp.283-288
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• 2016

The objective of this study was to investigate the microbial count of duck meat and duck meat products commercially available in Korea. High hydrostatic pressure (HHP) treatment was applied at 0.1, 300, 400, and 500 MPa for 5 min to enhance the microbiological safety of duck meats. The levels of total aerobic bacteria were in the ranges of 3.53-6.19 and 3.62-6.85 Log CFU/g in raw and smoked duck products, respectively. By DNA sequence analysis, we identified microorganisms responsible for spoilage, with the most common species in the raw and smoked duck products being Aeromonas spp. or Pseudomonas spp. and Leuconostoc mesenteroides, respectively. HHP treatment significantly reduced the levels of total aerobic bacteria in raw and smoked duck products. This study demonstrates that HHP treatment may be used to effectively improve the safety of raw and smoked duck meat products.

• Journal of Radiation Industry
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• v.7 no.2_3
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• pp.93-99
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• 2013

This study was conducted to evaluate the effect of gamma irradiation on the microbiological and sensory characteristics of frozen Bibimbap. Frozen Bibimbap vegetables were contaminated by microbial levels of $2.70{\sim}6.67log\;CFU\;g^{-1}$ in total aerobic bacteria. Frozen Bibimbap was contaminated by microbial levels of $4.8log\;CFU\;g^{-1}$ in total aerobic bacteria, but microorganisms in gamma-irradiated samples at above 25 kGy were not found at detection limit less then $1log\;CFUg^{-1}$. Sensory characteristics of the gamma-irradiated Bibimbap were decreased depending upon the irradiation dose, and sensory scores of the samples irradiated with doses higher than 10 kGy were significantly decreased. Therefore, the application of combination of the various food processing technology should be considered for the sterilization of Bibimbap, without any deterioration of quality occurred by high dose irradiation.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.1
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• pp.9-14
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• 2022

Packages of different atmospheres (air (control), 100% CO₂, vacuum, and vacuum + O₂ absorber) were prepared for 0.4 kg rice cake (ddukgukdduk) using gas-barrier plastic film and stored at 10℃ for 11 days. The stored products were evaluated in their packages atmosphere, total aerobic bacteria, yeast and molds, texture and sensory quality during storage period. In the air package, the O₂ concentration decreased from initial 21% to 16% on storage 4 days and the CO₂ concentration increased to 23% on storage of 11 days, which resulted from the growth of microorganisms. CO₂ concentration decreased from initial 98% to 36% on storage 11 days in the 100% CO₂ package. It is reasoned that CO₂ was dissolved into the product reducing the volume of the package. Vacuum and vacuum +O₂ absorber package maintained shrunk vacuum condition until 11 days of storage. Total aerobic bacteria count increased significantly in the control package (6.41 log (cfu/g) after 11 days) compared to the 100% CO₂ package (4.96 log (cfu/g) after 11 days). Yeast and molds were 6.66 in control package, 3.43 in 100% CO₂ package, 4.66 in vacuum package, and 3.78 in vacuum + O₂ absorber package after 11 days. There was no significant difference between control and the other treatments for the texture of the stored products. Sensory quality was the worst in control package on the storage of 8 days. All treatment groups except control improved the quality preservation, but vacuum and vacuum + O₂ absorber packages suffered from cracking of the product. Thus 100% CO₂ flushing is suggested as a desired packaging condition.

• Journal of Nutrition and Health
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• v.31 no.3
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• pp.305-314
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• 1998

Microflora in 14 breast-fed(BF) and 15 formula-fed(FF) infants were investigated before (2-3 months after birth) and after weaning (5-7 months birth) to find the floral differences between the two lactation groups and the floral changes after weaning. Bifidolbacteria showed the highest count among the species of microflora in the BF group before and after weaning, but in the FF group, streptococci showed the highest count before weaning and bifidobacteria after weaning. Before weaning , the count of bifidobacteria, lactobacilli and total acaerobes were significantly higher in the BF group than in the FF. However, the frequencies of clostridia and klesidella , along with the counts of streptococci and eubacteria, were higher in the FF group. After weaning , the only difference was that the total count of aerobic bacteria was higher in the BF group. The counts of streptococci in the BF group and lactobacilli and total anaerobes in the FF group after weaning were significantly higher than before weaning. However, the count of total aerobes in the FF group after weaning was significantly lower than the count before weaning.

• Microbiology and Biotechnology Letters
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• v.40 no.3
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• pp.190-196
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• 2012

In this study, a total of more than 1,000 bacteria, including 739 species of aerobic bacteria, 80 species of urease producing bacteria and 303 species of photosynthetic bacteria, were isolated from red-pepper field soils located in the Gyeongsan Province of the Republic of Korea. Amongst these, 158 species of aerobic bacteria, 70 species of urease producing bacteria and 228 species of photosynthetic bacteria were found to be auxin producing soil bacteria through quantification analysis with the Salkowski test. The latter groupings were then tested for antifungal activities to ${\beta}$-Glucanase and siderophore using CMC congo red agar and CAS blue agar media. In addition, the selected strains were examined for antifungal activity against various phytopathogenic fungi on PDN agar media. Six strains; BCB14, BCB17, C10, HA46, HA143, and HJ5, were noted for their ability to both produce auxin and act as antifungal substances. 16S rDNA sequence comparison analyses of these six strains identified them as Bacillus subtilis BCB14, B. methylotrophicus BCB17, B. methylotrophicus C10, B. sonorensis HA46, B. subtilis HA143, and B. safensis HJ5.