• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.31 no.6
• /
• pp.835-841
• /
• 1998

The antimicrobial activities of horseradish ( Wasahia japonica) root extract against 4 kinds of food poisoning bacteria and 3 kinds of molfs were examined. The antimutagenic activity of horseradish ( Wasahia japonica) root extracts was also examined by Ames test with Salmonella tyhimurium TA 98 The antimicrobial activities of distilled water extracts from horseradish root were stronger than those of ethanol extracts, and stronger against molds than bacteria. Of the kinds of bacteria, Vibrio parahaemolyticus was best inhibited by the distilled water extracts from horseradish root. The antimicrobial activity of distilled water extracts from horseradish root were stronger against 3-Amino-1, 4-dimethyl-5H-pyrido{4,3-b}indole than 2-Amino-3,-8-dimethylimidazo-[4,5-f]quinoxaline.

• Fisheries and Aquatic Sciences
• /
• v.25 no.5
• /
• pp.287-297
• /
• 2022

The objective of this study was to evaluate the probability of norovirus foodborne illness by raw oyster consumption. One hundred fifty-six oyster samples were collected to examine the norovirus prevalence. The oyster samples were inoculated with murine norovirus and stored at 4℃-25℃. A plaque assay determined norovirus titers. The norovirus titers were fitted with the Baranyi model to calculate shoulder period (h) and death rate (Log PFU/g/h). These kinetic parameters were fitted to a polynomial model as a function of temperature. Distribution temperature and time were surveyed, and consumption data were surveyed. A dose-response model was also searched through literature. The simulation model was prepared with these data in @RISK to estimate the probability of norovirus foodborne. One sample of 156 samples was norovirus positive. Thus, the initial contamination level was estimated by the Beta distribution (2, 156), and the level was -5.3 Log PFU/g. The developed predictive models showed that the norovirus titers decreased in oysters under the storage conditions simulated with the Uniform distribution (0.325, 1.643) for time and the Pert distribution (10, 18, 25) for temperature. Consumption ratio of raw oyster was 0.98%, and average consumption amount was 1.82 g, calculated by the Pert distribution [Pert {1.8200, 1.8200, 335.30, Truncate (0, 236.8)}]. ₁F₁ hypergeometric dose-response model [1 - (1 + 2.55 × 10^-3 × dose)^-0.086] was appropriate to evaluate dose-response. The simulation showed that the probability of norovirus foodborne illness by raw oyster consumption was 5.90 × 10^-10 per person per day. The annual socioeconomic cost of consuming raw oysters contaminated with norovirus was not very high.

• Journal of Food Hygiene and Safety
• /
• v.35 no.5
• /
• pp.459-467
• /
• 2020

In this study, we investigated the changes in both ambient temperature and microbial contamination of fresh convenience foods (FCFs) caused by the behavior of consumers after purchase. According to consumer survey results, it took 0.5 to 3 h put the purchased FCF in a home refrigerator or consume it. Only aerobic bacteria and Staphylococcus aureus (below maximum permitted limit) were detected in FCFs obtained from a local market. During storage of FCFs in a vehicle trunk for up to 3 h. the external and internal temperatures of FCFs were found to be 19 and 18.5℃ in spring, 44 and 42℃ in summer, 31.3 and 29.2℃ in autumn, and 17.6 and 16.8℃ in winter, respectively. Changes in contamination levels of aerobic bacteria on FCFs stored in a vehicle trunk for up to 3 hours are as follows: 2.72 → 3.41 log CFU/g in spring, 3.11 → 4.32 log CFU/g in summer, 3.08 → 3.81 log CFU/g in autumn, 2.71 → 3.36 log CFU/g in winter. S. aureus exceeding the tolerance was detected even when the FCFs were stored in a vehicle trunk for 1 h in summer and autumn and 2 h in spring and winter. Among three boxes (corrugated box, styrofoam box, and corrugated box coated with an aluminum film), the styrofoam box maintained the lowest temperature and showed the lowest growth rate of microorganisms on FCF after storage for 3 h in the vehicle trunk depending on whether ice was added. These results indicated that the possibility of food poisoning occurs when FCFs are exposed to the external environment. It is necessary to provide guidelines regarding storage temperature and allowable time for safe consumption of FCFs after purchase.

• The Korean Journal of Food And Nutrition
• /
• v.14 no.6
• /
• pp.548-561
• /
• 2001

Listeria spp. from sea water, fishes and shellfishes have been troubled in many countries. So we exam ined its distribution rates, biochemical characteristics of a separated strain, growth curve of pH at set times to 4 species of standard strain, and yes or no of growth inhibition for precautionary measure of food poisoning by L. monocytogenes, garlic, mustard, wasabi, and green tea extracts including sensitivity of antibiotics 10 species. As its results, check numbers of its positivity to Listeria spp. were 32 species in total examination body 200 species, and its isolation rates were 16%, L. innocua was 14.0%, L. monocytogenes 1.0%, and L. seeligeri 1.0% by the strain species. All the standard strain of 4 species showed growth inhibition bellow pH 3.0, its pH conditions of the optimum growth at 7.0∼8.0, and its growth was more active in alkali co]tuition than in acid condition. Its growth inhibition examination by garlic extracts had an the worst effects with O.D values of 0.078∼0.210. But the case of mustard and wasabi had weakened effect, and the case of green tea had some effect as the time went by. The results of sensitivity examination of antibiotics 10 species were as fellows. L. innocua of the 16 cases showed sensitivity of 100% in all 5 species, Ampicillin, etc, and Ciprofloxacin showed sensitivity of 43.7% and gentamicin, 93.7%. But tetracycline showed tolerance of 31.3% , cefotaxine. 75%, nalidixic acid, 100%. L. monocytogenes of the 6 cases showed sensitivity of 100% in all 6 species, ciprofloxacin, etc.

• Korean Journal of Poultry Science
• /
• v.33 no.2
• /
• pp.159-164
• /
• 2006

To investigate the effects of salt contents in diet and water on the growth of broiler chicks, 288 heads of Hubbards strain chicks, were fed with com-soybean meal diets containing 0, 0.25, 0.5, 0.75 1.0, 2.0, 3.0, or 4.0% salt from 1d to l4d posthatching. And 180 chicks were also supplemented with salt to their water at 0, 0.1, 0.2, 0.5 or 1.0%. Feed intake and weight gain tended to decrease as the salt levels in diets increased and those were the lowest in 4% group as 481 g and 168 g, however, mortality was the highest in 4% group as 75.0%. As for the salt levels in water, feed intake and weight gain were low as 427 g and 162 g in 1% group, while mortality was 77.8%. Salt poisoning chicks were shown with thirsty, appetite deficiency, rising impossibility, sleepiness, or convulsions, and in autopsy, were shown with ascites, hydropericardium, cardiac hypertrophy, hemorrhage of eyelid, hemorrhage of trachea, hemorrhage of intestine, etc. Conclusively, salt content above 4% in diet or 1% in water could reduce the performance in broiler chicks.

• Journal of Nutrition and Health
• /
• v.12 no.1
• /
• pp.59-68
• /
• 1979

This work was carried out to detect the enterobacterial contamination in summer kimchies and their antagonis tic activity with lactic acid bacteria during kimchi fermentation. And obtained results were as in the followings. 1) Severe cases of enterobactrial contamination were found in every kimchi material and in the first step of summer kimchi fermention. 2) Some pathogenic or food poisonous strain of Salmonellaspp. was identified among the contaminated enterobacteria. 3) Pathogenic strains of Salmonella typhi, Shigella flexneri or E. coli which were added to kimchi fermention, were contineously detected for 10days at the temperature of $10^{\circ}C$. Food poisonous strain of Vibrio parahemolyticus was more resistant than the above stains in the kimchi fermentation. 4) And in summer condition(over $30^{\circ}C$) the added pathogenic strains of enterobacteria were also detected for 2 day at pH of 4.5 kimchi fermentation. 5) The antagonistic activity of enterobacteria in lactate buffer solution of pH 4.8 was more stron than that in the kimchi fermentation at $30^{\circ}C$ of summer condition. 6) According to the above results, sanitary washing processes for every kind of kimchi material (vegitables) are required to reduce the enterobacterial concentration which is usually contaminated. And some fermentation period is also required to avoid the possible kimchi food poisoning.

• Asian-Australasian Journal of Animal Sciences
• /
• v.25 no.2
• /
• pp.278-285
• /
• 2012

Poultry products are an important source of Salmonella enterica. An effective way to reduce food poisoning due to Salmonella would be to breed chickens more resistant to infection. Unfortunately host responses to Salmonella are complex with many factors involved. To learn more about responses to Salmonella in young chickens of 2 wk old, a cDNA Microarray containing 13,319 probes was performed to compare gene expression profiles between two chicken groups under control and Salmonella infected conditions. Newly hatched chickens were orally infected with S. enterica serovar Enteritidis. Since the intestine is one of the important barriers the bacteria encounter after oral inoculation, intestine gene expression was investigated at 2 wk old. There were 588 differentially expressed genes detected, of which 276 were known genes, and of the total number 266 were up-regulated and 322 were down-regulated. Differences in gene expression between the two chicken groups were found in control as well as Salmonella infected conditions indicating a difference in the intestine development between the two chicken groups which might be linked to the difference in Salmonella susceptibility. The differential expressions of 4 genes were confirmed by quantitative real-time PCR and the results indicated that the expression changes of these genes were generally consistent with the results of GeneChips. The findings in this study have lead to the identification of novel genes and possible cellular pathways, which are host dependent.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.28 no.1
• /
• pp.15-22
• /
• 1995

To study ecological properties of Vibrio cholerae non-Ol and Vibrio mimicus which have been described as new food poisoning bacteria recently, the influence of factors such as temperature, salinity, pH and chemical oxygen demand (COD) on detection rate and density of these bacteria were evaluated. Fifty four seawater samples and 49 bottom deposit samples from estuary of Kum river from March 26th, 1993 to February 22nd, 1994 were used for this study. The detection rate of V cholerae non-O1 were $16.7\%$ for seawater and $10.2\%$ for bottom deposit, respertively. The total detertion rate of V. cholerae non-O1 $(11.7\%)$ was a little higher than V mimicus $(10.7\%)$. Both V choierae non-O1 and V. mimicus were mainly detected in estuary water of which showed temperature $24^{\circ}C$ above and salinity $10\%o$ below. These bacteria were also detected in bottom deposit on January when the water temperature was $3.5^{\circ}C$. From these results, we supposed that temperature, salinity and organic material were important factors to growth of V. cholerae non-O1 and V. mimicus. V cholerae non-O1 might be grown better than V. mimicus under the fluctuating aquatic environmental condition such as salinity.

• Preventive Nutrition and Food Science
• /
• v.7 no.2
• /
• pp.168-173
• /
• 2002

Gastrointestinal infections kill over two million people each year, and pathogen contamination of livestock causes many cases of food poisoning. Two candidate intestinal probiotic strains, L. rhamnosus GR-1 and L. fermentum RC-14 were found to inhibit the growth of Salmonella typhi, Shigella dysenteriae, E. coli O157:H7, Listeria monocytogenes, L. innocua, Enterococcus faecalis, and Bacteroides fragilis. In a series of mouse experiments, L. rhamosus GR-1 and L rhamnosus GG protected against S. typhimurium infection and translocation to the liver and spleen, reduced mortality and induced intestinal phagocytic and immunoglobulin responses. In a second series of experiments, the combination of L. rhamnosus GR-1 and L. fermentum RC-14 was superior to L. rhamnosus GG and placebo in protecting the mice from the lethal effect of salmonella. In summary, the use of combinations of probiotic lactobacilli as dietary supplements or foods could be considered for people at high risk of salmonella intestinal infection. Given the post-infection complications that can arise, such natural methods warrant further exploration especially given the increasing problem of antibiotic resistance and the lack of alternative measures available to many developing countries.

• Applied Chemistry for Engineering
• /
• v.32 no.5
• /
• pp.516-523
• /
• 2021

A study using selective catalytic reduction (SCR) was conducted in conjunction with ammonia as a reducing agent for controlling nitrogen oxides, a typical secondary inducer of fine dust in the atmosphere. For NH₃-SCR experiments, a commercial catalyst of V/W/TiO₂ only and also V/W-Sb/TiO₂ catalyst with Sb were used, and phosphorous durability was confirmed. As a result of NH₃-SCR experiments, it was confirmed that the addition of Sb to V/W/TiO₂ had durability against phosphorous. In addition, the physical and chemical properties were comparatively analyzed through BET, XPS, H₂-TPR, NH₃-TPD, and FT-IR analysis. From the anaylsis results, when Sb was added to V/W/TiO₂ catalyst, P was also added resulting in the formation of SbPO₄ and the generation of VOPO₄ was suppressed. The phosphorous durability was confirmed by maintaining the redox characteristics of the catalyst before P was added.