• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.9
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• pp.1445-1450
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• 2004

The plum (Prunus salicina L., cv. ‘Soldam’) fruits were harvested at different growth stages, and then extracted using 80% methanol, respectively. The methanol extracts of plum were investigated for their growth inhibition on 6 kinds of human cancer cells using MTT assay and for their activity to induce quinone reductase (QR) in murine Hepa1c1c7 cells. Among various methanol extracts of plum, the plum 1~4 (immature fruit), which thin out 10~25 days before final harvest, showed higher anticarcinogenic activity against 5 kinds of cancer cells than plum 5~9 (intermediate-mature and mature fruit). Especially, plum 1 and 2 were exhibited the strongest growth inhibiting activities to AGS, HepG2 and MDA cancer cells. Also the plum extracts induced the activity of QR, an anticarcinogenic marker enzyme, in Hepa1c1c7 cells while the induction of QR activities by adding plum extracts were shown to be a little difference depending on growth stages. These results suggested that methanol extracts of immature plum can be considered as an effective natural cancer chemoprevention materials.

• Journal of Food Hygiene and Safety
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• v.25 no.1
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• pp.59-64
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• 2010

The effects of vinegar, alcohol and ascorbic acid on the color, microorganism, sensory properties and flavor pattern of minced ginger (MG) were investigated during storage for 28 days at $30^{\circ}C$. The values of L (lightness), a (redness) and b (yellowness) of the control (T-0) and all the treatments changed slightly at the initial stage of storage, however the elapse of time accelerated the changes. The total bacterial counts of T-0 showed $5.37{\times}10^7\;CFU/g$ at the initial stage, but the MG-treatments decreased the bacteria above 4 log compared to T-0. It was showed that the additives were effective for inhibition of the growth of microorganism. Sensory properties of flavor intensity test showed no significant difference between T-0 and MG-treatments (p < 0.05). The result of volatile flavor contents of electronic nose analyzer (ENZ) showed that MG-treatments (T-I, T-II, T-III) was recognized stronger than non-treatment at the initial stage, but the change of flavor compound were stabilized soon regardless of type or quantity of additives during total storage period at $30^{\circ}C$.

• Journal of Food Hygiene and Safety
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• v.32 no.5
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• pp.363-370
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• 2017

In this study, we stored frozen shrimp (Litopenaeus vannamei) at $4^{\circ}C$ during 12 days and investigated the effect of chitosan coating with natural preservatives (0.05% carvacrol, 0.05% thymol) on the growth of microorganism (mesophilic bacteria, psychrophilic bacteria, Pseudomonas spp., $H_2S$ producing bacteria) and physiological characteristics (total volatile basic nitrogen and pH) and sensory evaluation (appearance, odor and general acceptance). Chitosan coating with natural antimicrobial compounds (0.05% carvacrol and 0.05% thymol) had inhibited the growth of all the target microorganism and showed the significant antimicrobial activity (p < 0.05) to mesophilic bacteria, psychrophilic bacteria and $H_2S$ producing bacteria until 12 day (the last day of this study). These treated groups had showed the significant difference (p < 0.05) in total volatile basic nitrogen and all the sensory characteristics but not in pH. Therefore, chitosan coating combined with natural antimicrobial compounds (0.05% carvacrol and 0.05% thymol) showed the effective antimicrobial activity on major spoilage microorganism on shrimp and could be used to elongate the shelf life of refrigerated shrimp.

• Culinary science and hospitality research
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• v.8 no.3
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• pp.249-257
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• 2002

Gamma irradiation(1~10 kGy) was applied to chicken for the evaluation of their microbiological safety. In 3kGy-irradiated sample, the initial level of microbial contamination in chicken was 1.8$\times$10$^4$CFU/g (Coliforms), 2.2$\times$10$^3$CFU/g(Salmonella) and 2.7$\times$10$^3$CFU/g(Listeria), All kinds of contaminated microorganism were sterilized by 7kGy-irradiation. Also, irradiation followed by freeze storage at the same time was very effective in inhibiting bacterial growth. The pH was slightly increased during storage period and titratable acidity decreased. However, no significant changes in pH and acidity were observed by gamma irradiation.

• Journal of Microbiology
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• v.40 no.4
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• pp.267-273
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• 2002

Urinary tract infection (UTI) is one of the most common domiciliary and nosocomial bacterial infections prevalent in both males and females. UTI is diagnosed on the basis of clinical symptoms, microscopy and culture of urine. In order to evaluate the efficacy of microscopic detection for presumptive diagnosis of UTI we analyzed urine samples of Nepalese patients. We have conducted Gram staining and counting of pus cells, red blood cells (RBC) and epithelial cells. We observed that RBC and epithelial cell counts were not sensitive enough to be used for presumptive diagnosis of UTI. However, pus cell counts as well as Gram stain are sensitive and significant enough to presume UTI. When the Gram stain result was compared with the culture result, it was statistically significant. From this, we suggest that Gram stain of centrifuged urine is a very sensitive screening method to detect bacteriuria. In addition, we found that E. coli was the most predominant microorganism causing UTI and nitrofurantoin was the most effective antibiotic against the isolated urinary pathogens.

• Proceedings of the Korean Society of Crop Science Conference
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• 2005.10b
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• pp.182-183
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• 2005

• Journal of environmental and Sanitary engineering
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• v.13 no.2
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• pp.156-164
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• 1998

This study was performed to select media for the development of biological activated carbon process. Using activated carbon made by Norit, Calgon, Samchully Co., removal efficiency of humic acid by the isothermal adsorption test and biodegradation of organic matters by microbes attached to BAC and observation and counting of microbes attached to BAC were examined. The removal efficiency of humic acid with dose of activated carbon was influenced by initial concentration. Compared with other activated carbon, Norit was found to be most effective in view of adsorption capacity, biodegradation of organic matter, and attachment characteristics of microorganism. In conclusion, Norit which has high adsorption capacity and good biodegradation of organic matter was recommended for selecting media in BAC process.

• Journal of Environmental Health Sciences
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• v.16 no.2
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• pp.127-133
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• 1990

The purpose of the study was to identify the characteristics of the pathogenic microorganism Actinobacillus actinorayceteracomitans. The experiments of this study consist of the decision of existence or nonexistence of Actinobacillus actinorayceterncoraitans in the air of dental clinics, the effect of sugar on the growth of Actinobacillus actinorayceteracoraitans, and the sensitivity of Actinobacillus actinoraycetemcoraitans to Fluorine and antibiotics. The results of the experiments are as follows. 1. Actinobaeillus actinornyceteracornitans did not exist in the air of 4 dental clinics in Seoul 2. The growth of Actinobacillus actinornycetemcornitans in the media containing glucose or sucrose was faster than in the media without these, and glucose was more effective than sucrose. 3. Actinobacillus actinomyceteracoraitans was not susceptible to Fluorine at concentration between 0 ppm and 300 ppm. 4. Order of sensitivity of Actinobacillus actinomycetemcomitans to antobiotics was as follows: Tetracycline > Kanamycin > Ampicillin.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.6
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• pp.571-575
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• 2005

A simple, but effective on-line method for estimating the mycelial cell mass concentration from agitation speed data, a most readily-available process variable, has been developed for DO-stat cultures of Agaricus blazei. The dynamic change of dissolved oxygen concentration (DOC) in the initial transient period and the change in yield were considered in the development of the estimation algorithm or estimator. Parameters in the estimation algorithm were calculated from the agitation speed data at 20% of DOC. The proposed estimator could accurately predict the cell mass concentration regardless of DOC levels in the tested range of $10{\sim}40%$, showing a good extrapolation capability.

• The Korean Journal of Community Living Science
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• v.21 no.1
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• pp.13-18
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• 2010

This study was performed to investigate the antimicrobial effects of Euphorbia humifusa ethanol-extract against food-borne pathogens. The growth inhibitory effects of the extract at a concentration of 250, 500, 1,000 or 2,000 mg/L on food poisoning microorganism were determined against Salmonella typhimurium, Listeria monocytogenes, Yersinia enterocolitica, Escherichia coli O157:H7 and Staphylococcus aureus. The microorganisms growth was not affected by the extract at the concentration up to 250 mg/L, but was significantly (p<0.05) inhibited by the extract at a concentration higher than 1,000 mg/L. The extract of Euphorbia humifusa had strong antimicrobial activity against all test strains at a concentration of 2,000 mg/L. The results in the present study demonstrate antimicrobial effects of Euphorbia humifusa ethanol-extract against food-borne pathogens, suggesting that Euphorbia humifusa could be an effective natural antibacterial agent in food.