T-2 toxin and HT-2 toxin, belong to type A trichothecences, are the most toxic mycotoxins among the trichothecene family. These mycotoxins are commonly found in cereals such as maize, wheat, barley, oats and rice, and their occurrence in food can be of concern. This review investigated the current trends of patents and researches on T-2 toxin and HT-2 toxin pertaining to natural occurrence, toxicity, metabolism, risk assessment, analytical and screening methods, and reduction/detoxification techniques. As compared with other Fusarium mycotoxins, there are limited data for natural occurrence and risk assessment, and regulatory limit and official analytical methods on T-2 toxin and HT-2 toxin in domestic and foreign countries. In particular, selective deacetylation at the C3 and/or C4 positions of T-2 toxin by carboxyesterase present in foods was reported to cause the disappearance of T-2 and the extremely high HT-2 recoveries. Currently, regulatory limits for T-2 and HT-2 are under discussion in EU. For enforcement purposes it is essential to have available precise and reliable analytical methods applicable at the regulatory levels for the T-2 toxin and HT-2 toxin and relevant commodities. In addition, a further study on natural occurrence, risk assessment and reduction/detoxification techniques will be recommended.
Highly pathogenic avian influenza virus (HPAIV) is already panzootic in poultry and caused a considerable economic loss in poultry industry. In addition, HPAIV continues to cross species barriers to infect humans and other mammals, often with fatal outcomes. In this study, the virucidal efficacy of Citra-Kill® composed to quaternary ammonium chloride and citric acid was investigated against avian influenza H9N2 virus (AIV). A virucidal efficacy was determined with the viability of AIV contacted with the disinfectant in the allantoic membrane of chicken embryos. Citra-Kill® and AIV was reacted on the distilled water (DW), hard water (HW) or organic matter suspension (OM) condition. On DW condition, AIV was inactivated with 2,000 fold dilutions of Citra-Kill®. When the antiviral effect on HW condition was evaluated, the antiviral activity of the disinfectant showed on 1,500 fold dilutions against AIV. With the investigation of the antiviral effect of the disinfectant on OM condition, AIV was inactivated on 500 fold dilutions of Citra-Kill®. As Citra-Kill® possesses virucidal efficacy against AIV, the disinfectant solution can be used to limit the spread of animal viral diseases.
A total of 187 samples of leafy vegetables and fruits were acquired at traditional markets and department stores in Seoul, Korea. Samples were tested for microorganism distributions and for the presence of pathogenic bacteria. The aerobic mesophilic counts ranged between 2.5 and 9.4 log CFU/g, with the highest count recorded from the dropwort. Counts of psychrotrophic microorganisms were as high as those of the mesophilic microorganisms. Total coliform populations between 1.0 and 7.8 log CFU/g were found in 90.9% of the samples. Microbiological counts for fruits were very low. Escherichia coli was isolated in 24 (12.8%) samples. Staphylococcus aureus and Clostridium perfringens contamination were found in 15 (8.0%) and 20 (10.7%) samples. Salmonella species and Listeria monocytogenes were detected in 2.7 and 0.5% of samples, respectively. Among the total 187 samples, 8 samples were contaminated by more than two pathogens. E. coli O157:H7 was not detected in any of the samples. The microbial contamination levels determined in the present study may be used as the primary data to execute microbial risk assessment of fresh vegetables and fruits.
This study was conducted to evaluate the microbiological hazard on nursery school children's hands and to investigate the reduction effect of hand washing education. A total of 59 nursery school children's hands were tested. The average number of total aerobic bacteria was 3.72 ± 0.38 log CFU/hand. Five children's hands(2 male and 3 female) were positive(14.3%) for the coliform bacteria. These results showed that hand washing education are required repetitively. Among the pathogenic bacteria tested in this study, Staphylococcus aureus and Bacillus cereus were detected in 9(25.7%) and 16(45.7%) out of 35 their hands, respectively. Twelve out of sixteen B. cereus isolates(70.0%) produced enterotoxin. The results indicate that the hand hygiene of nursery school children needs to be improved. Comparing before and after hand washing in educated and non-educated group, the reduction effect of total aerobic bacteria on their hands was 0.42 and 0.60 log CFU/hand, respectively. The educated group showed 0.18 log CFU/hand higher reduction effect than non-educated group but microorganism did not eliminate perfectly. From the results, using a hand sanitizer after washing with soap and the continuous hand washing education are required to control the contaminated bacteria on nursery school children's hands.
The current standard for testing tetrodotoxin (TTX) in foodstuffs is the mouse bioassay (MBA) in Korea as in many other countries. However, this test suffers from potential ethical concerns over the use of live animals. In addition, the mouse bioassay does not test for a specific toxin thus a sample resulting in mouse incapacitation would need further confirmatory testing to determine the exact source toxin (e.g., TTX, STX, brevotoxin, etc.). Furthermore, though the time of death is proportional to toxicity in this assay, the dynamic range for this proportional relationship is small thus many samples must be diluted and new mice be injected to yield a result that falls within the quantitative dynamic range. Therefore, in recent years, there have been many efforts in this field to develop alternative assays. High performance liquid chromatography (HPLC) coupled with mass spectrometry (MS) has been emerged as one of the most promising options. A LC-MS-MS method involves solid-phase extraction (SPE) and followed by analysis using an electrospray in the positive ionization mode and multiple reactions monitoring (MRM). To adopt LC-MS-MS method as alternative standard for testing TTX, we performed a validation study for the quantification of TTX in puffer fish. This LC-MS-MS method showed good sensitivity as limits of detection (LOD) of 0.03~0.08 μg/g and limits of quantification (LOQ) of 0.10~0.25 μg/g. The linearity (r2) of tetrodotoxin were 0.9986~0.9997, the recovery were 80.9~103.0% and the relative standard deviations (RSD) were 4.3~13.0%. The correlation coefficient between the mouse bioassay and LC/MS/MS method was higher than 0.95.
This study was carried out to investigate the toxicity of food Red No.2 in the Sprague-Dawley (SD) female rat for 4 weeks. SD rats were orally administered for 28 days, with dosage of 500, 1,000, 2,000 mg/kg/day. Animals treated with food Red No.2 did not cause any death and show any clinical signs. They did not show any significant changes of body weight, feed uptake and water consumption. There were not significantly different from the control group in urinalysis, hematological, serum biochemical value and histopathological examination. In conclusion, 4 weeks of the repetitive oral medication of food Red No.2 has resulted no alteration of toxicity according to the test materials in the group of female rats with injection of 2,000 mg/kg. Therefore, food Red No.2 was not indicated to have any toxic effect in the SD rats, when it was orally administered below the dosage 2,000 mg/kg/day for 4 weeks.
Salmonella spp. and Brucella spp. have caused a considerable disease of farmed animals and economic loss in animal farming and food industry. In this study, the disinfection efficacy of Vital-Oxidel®, a commercial disinfectant, composed to chlorine dioxide, betaine hydrochloride, and propylene glycol was evaluated against S. typhimurium and Brucella ovis. A bactericidal efficacy test by broth dilution method was used to determine the lowest effective dilution of the disinfectant following exposure to test bacteria for 30 min at 4oC. Vital-Oixdel® and test bacteria were diluted with distilled water (DW), hard water (HW) or organic matter suspension (OM) according to treatment condition. On OM condition, the bactericidal activity of Vital-Oixdel® against S. typhimurium and Brucella ovis was lowered compared to that on HW condition. As Vital-Oxidel® possesses bactericidal efficacy against animal pathogenic bacteria such as S. typhimurium and Brucella ovis, this disinfectant solution can be used to control the spread of bacterial diseases.
This study is a survey of regulatees' perception on main contents and enforcement effect of the Act, the retailers at food stores within Green Food Zone, for the effective enforcement of “The Special Act on the Safety Management of Children's Dietary Life” legislated in 2008. Percentage, frequency analysis, and T-test are derived from the survey carried out to the 175 retailers at food stores within Green Food Zone, across the country except Jejudo, for the two months March and April of 2011. The survey results are as follows. Over 80% of the respondents are aware of comprehensive policy for child food safety and the enforcement of 'the Special Act' and considering the rate of satisfaction on food safety information provided by government, over 90% of the respondents, virtually most of them, are satisfied. The rate of awareness of Green Food Zone is about 80% and that of outstanding business for children is about 50%, showing little perception of it. The comparison of the survey result of 2011 with that of 2010, which have the same questions to the retailers within Green Food Zone, still indicates a need for enhancement of understanding on absolute standard, though it showed fairly better improvement in general. Several proposals are given in this study based on the survey results, which will contribute to the children food safety and health improvement in the end.
Antibiotic resistance in animal isolates of enterococci is a public health concern, because of the risk of transmission of antibiotic-resistant strains or resistance genes to humans through the food chain. This study investigated phenotypic and genotypic resistances profile of tetracycline in 245 Enterococcus isolates from bovine milk. A total of 245 enterococci were isolated from 950 milk samples. The predominant strain was E. faecalis (n = 199, 81.2%) and E. faecium (n = 25, 10.2%). E. avium (n = 7, 2.9%), E. durans (n = 6, 2.5%), E. gallinarum (n = 4, 1.6%), and E. raffinosus (n = 4, 1.6%) were also isolated. Of the 245 enterococcal isolates 76.3% (n = 187) displayed tetracycline resistance (≥ 16 μg/ml). Of the 187 tetracycline-resistant isolates, 83.4% (n = 156), 16.1% (n = 30), and 26.7% (n = 50) possessed the genes tet(M), tet(L), tet(S) respectively. While 3.2% (n = 6) of the tetracycline- resistant isolates possessed all three genes tet(M) + tet(L) + tet(S), 8.6% (n = 16), 16.0% (n = 30), and 2.7% (n = 5) of them possessed two genes tet(M) + tet(L), tet(M) + tet(S), and tet(L) + tet(S) respectively. The tetracycline resistance pattern investigated in this study was attributable mainly to the presence of tet(M).
In this study, a method was developed using molecular biological technique to distinguish an authenticity of meats for processed meat products. The genes for distinction of species about meats targeted at 12S or 16S genes in mitochondrial DNA and the species-specific primers were designed by that PCR products' size was around 200bp for applying to processed products. The target materials were 10 species of livestock products and it checked whether expected PCR products were created or not by electrophoresis after PCR using species-specific primers. The results of PCR for beef, pork, goat meat, mutton, venison, and horse meat were 131, 138, 168, 144, 191, and 142 bp each. The expected PCR products were confirmed at 281, 186, 174, and 238 bp for chicken, duck, turkeymeat, and ostrich. Also, non-specific PCR products were not detected in similar species by species-specific primers. The method using primers developed in this study confirm to be applicable for composite seasoning including beefs and processed meat products including pork and chicken. Therefore, this method may apply to distinguish an authenticity of meats for various processed products.
Fish contain both the neurotoxin methyl mercury (MeHg) and nutrients important for brain development. The developing brain appears to be most sensitive to MeHg toxicity and mothers who consume fish during pregnancy expose their fetus prenatally. Although brain development is most dramatic during fetal life, it continues for years postnatally and additional exposure can occur when a mother breast feeds or the child consumes fish. This raises the possibility that MeHg might influence brain. We evaluated the relationship between fish consumption and mercury exposure levels in umbilical cord blood of the pregnant women of the city of Tongyeong city, Korea. A total of 159 pregnant women residing in the city of Tongyeong, Korea were recruited for the study between October 2010 and March 2011. Fish consumption was evaluated using food frequency questionnaires including detailed questions on fish consumption. We used ANOVA to estimated the particular relevance between the frequency of fish consumption and the umbilical cord blood mercury concentration, and other various factors. The average mean concentration of mercury levels in umbilical cord blood of pregnant women who participated in our study were 2.69 ± 2.50 ppb, ranging from 0.01 to 14.80 ppb. The mean concentration of umbilical cord blood mercury exposure was lower than the level recommended by WHO (5.0 ppb), but the mercury exposure level exceeded the WHO recommended in 17 (10.7%) cases of umbilical cord blood. Mercury levels in cord blood of pregnant women were 2.04 ± 2.00 ppb, ranging from 0 to 8.00 ppb in below 29 years old and 3.18 ± 2.74 ppb, ranging from 0.01 to 14.80 ppb in more 30 years old. In this study, there was a significant difference for the frequency of eating fish between the groups (p < 0.01). The level of the groups that ate fish 3 to more times per week (4.15 ± 4.02 ppb) was significant higher as compared with the level of other groups that ate fish 1 to times per week (2.63 ± 2.22 ppb) and none per week (1.06 ± 1.44 ppb), respectively. We found that the mercury concentration of umbilical cord blood associate with fish consumption and this was statistically significant and this fact revels that fish consumption is positively related to mercury levels in the umbilical cord blood. We need systematic and periodic research on the general population to prevent mercury poisoning, which can be cause by low-level mercury exposure from dietary intake such as chronic fish consumption
The present study was evaluated the antibacterial effect of the combination of Coptidis rhizoma, Glycyrrhiza uralensis Fischet, Schizandra chinensis and Corni Fructus(1:1:1) extracts(CGSC10). Furthermore, the effectiveness of CGSC10, sodium chlorate, and the combination of CGSC10 and sodium chlorate(CGSCS10) against E. coli O157:H7 infection was studied using ICR female mice. During the incubation period, the dose of 5, 10, and 20% CGSC10 was inhibited the growth of E. coli O157:H7 by 34.7, 60.2, and 76.4%, respectively. For 7 days after single challenge with E. coli O157:H7, forty female ICR mice were divided into four experimental groups which were administered in drinking water with saline, 10% CGSC10, 15 mM sodium chlorate, and CGSCS10, respectively. On the 3rd day, the number of E. coli O157:H7 in mouse feces was significantly decreased by administration of CGSC10, 15 mM sodium chlorate, and CGSCS10 (p < 0.001). On the 7th day-after administration, CGSC10, sodium chlorate, and CGSCS10 were decreased the number of E. coli O157:H7 by 27.1, 67.7, and 83.3%, respectively. According to the results of the present study, administration of CGSCS10 to mice can reduce the severity of E. coli O157:H7 infection. In addition, it is suggested that CGSCS10 represents a good candidate for the treatment of enteric infections in domestic animals.
This study was investigated to determine the contamination levels of total aerobic bacteria, coliform group, E. coli and food-borne pathogens of side dishes from 2 traditional markets (100 samples) and 2 super markets (100 samples) located on Ulsan. The levels (range) of total aerobic bacteria was 4.75 log CFU/g (1.60~6.92 log CFU/g) in traditional market and 4.62 log CFU/g (2.00~6.46 log CFU/g) in super market, respectively. Coliform was detected in 64 and 66 samples sold at traditional markets and super markets, respectively. E, coli was detected in 4 and 6 samples sold at traditional markets and super markets, respectively. The food-borne pathogens, namely Bacillus cereus and Listeria monocytogenes were detected in 1 sample sold at traditional markets, respectively, and Bacillus cereus was detected in 4 samples sold at super markets. However, other pathogens such as Salmonella spp., Shigella spp., Vibrio parahaemolyticus, Yersinia enterocolitica, Clostridium perfringens, Camphylobacter jejuni and Pathogenic E. coli were not detected. The Saengchae and Seasoned Jeotgal were relatively vulnerable compared to the others in the food-borne pathogens.
This study was designed to evaluate a repeated oral dose toxicity and immunomodulating activity of Pulsatilla koreana and Artemisiae annuae in Sprague-Dawley rats. The female rats were treated with Pulsatilla koreana and Artemisiae annuae of control group, low group (0.5 ml/kg), medium group (1 ml/kg), high group (2 ml/ kg) for distilled water, intragastrically for 4 weeks, respectively. To ensure the safety of Pulsatilla koreana and Artemisiae annuae such as the following were observed and tested. We examined the body weight, the feed intake, the clinical signs, the ophthalmological test, the hematological and the serum biochemical analysis. We also observed the histopathological changes of liver and kidney in rats. Hematological results were the increase of neutrophils, lymphocytes and monocytes in the high dose group of Pulsatilla koreana. The increase immune cells in the high dose group of Pulsatilla koreana might immunomodulating activity. No significant differences in body weight, feed intake, serum biochemical analysis and histopathological between control and fed group were found. In conclusion, Pulsatilla koreana and Artemisiae annuae is physiologically safe and improve immunomodulating activity.
We compared between an automated most-probable-number technique TEMPO®TVC and traditional plating methods PetrifilmTM for estimating populations of total aerobic bacteria in various livestock products. 257 samples randomly selected in local retail stores and 87 samples inoculated with E. coli ATCC 25922, Staphylococcus aureus ATCC 12868 were tested in this study. The degree of agreement was estimated according to the CCFRA (Campden and Chorleywood Food Research Association Group) Guideline 29 and the agreement indicates the difference of two kinds methods is lower than 1 log base 10(log10). The samples of hams, jerky products, ground meat products, milks, ice creams, infant formulas, and egg heat formed products were showed above 95% in the agreement of methods. In contrast, proportion of agreement on meat extract products, cheeses and sausages were 93.1%, 92.1%, 89.1%, respectively. One press ham and five sausages containing spice and seasoning, two pork cutlets containing spice and bread crumbs, two meat extract product and two natural cheeses and one processing cheese with a high fat content, and one ice cream containing chocolate of all samples showed the discrepancy. Our result suggest that TEMPO®TVC system is efficient to analyses total aerobic bacteria to compare manual method in time-consuming and laborious process except livestock products having limit of detection.