Norovirus (NoV) is a major cause of food poisoning outbreaks in Korea. Most NoV outbreaks originate from envi-ronmental contamination, but bivalves such as oysters are also important vectors. Oyster ...Crassostrea gigas contami-nation by NoV has been reported in Korea, but no quantitative analyses of NoV have been performed. We investi-gated the NoV concentration in 21 oyster samples from a Korean commercial oyster-growing area with confirmed fecal contamination from January to December 2012, using real-time reverse transcription-polymerase chain reac-tion. Additionally, we assessed the NoV concentration after heating to investigate the effects of heat treatment on NoV-infected oysters. In NoV-positive samples, the cycle threshold (Ct) values were 37.43-39.41 and 36.77-39.30, while viral concentrations were 8.97×102-2.24×102 and 3.05×102-7.47×101 copies/g for genogroups I and II, respec-tively. After heat treatment, NoV genogroup I decreased by 83.4%, 88.0%, 89.4% and 100% at 60℃, 68℃, 70℃, and 100℃, respectively, for 15 min, while genogroup II respectively decreased by 67.3%, 76.3%, 80.1%, and 89.8% under the same conditions.
The contamination status of Vibrio parahaemolyticus in commercially valuable shellfish from the south and west coasts of Korea and the antimicrobial resistance patterns of isolated V. ...parahaemolyticus were investigated from July through October, 2011. The range of V. parahaemolyticus concentrations in oysters Crassostrea gigas and short neck clams Venerupis philippinarum was <30~290 MPN/100 g and <30~46,000 MPN/100 g, respectively, and greater than 10,000 MPN/100 g of V. parahaemolyticus was detected from 7 of 40 short neck clams. During the survey period, 436 strains of V. parahaemolyticus were isolated (129 from oysters and 307 from short-neck clams) and the antimicrobial resistance patterns of all of the isolates were examined. Antimicrobial resistance against at least one antibiotic was seen in 79.8% of the oyster isolates (103 strains) and 63.8% of the short neck clam isolates (196 strains). The anti-microbial resistance patterns were relatively simple because the antimicrobial resistance of the isolates was simply due to resistance to ampicillin. Only one oyster isolate and three short neck clam isolates showed multiple antibiotic resistance, i.e., resistance against more than four antibiotics.
The geographical distribution of the toxic blue-lined octopus (commonly known as the blue-ringed octopus), Hapalochlaena spp., around the East/Japan Sea was investigated. Observation records of the ...octopus were gathered using commercial search engines on the Internet. A questionnaire to complement and enhance the base data was conducted that targeted fishermen from areas where the octopus was most likely to occur, i.e., the southeast coast and islands of Korea in the East/Japan Sea. Overall, 32 observational records of the blue-lined octopus were found from Korea and Japan. In Korea, only one record, from 2003, was found on a website; none of the 240 fishermen who participated in the questionnaire reported seeing blue-lined octopus. However, a total of 31 observations of the blue-lined octopus from 2004 to July 2010 were found from 17 different regions in the East/Japan Sea and neighboring waters in Japan. Twenty-two cases were from coastal Honshu Island, and nine were from the west coast of Kyushu Island, Japan. The northern distributional boundary of the blue-lined octopus on the Japanese coast was off Fukui Prefecture around latitude $36^{\circ}$10' N. Our results indicate that the blue-lined octopus is distributed extensively along the Japanese coast, at a low frequency, in the East/Japan Sea.
Simultaneous determination of macrolide residues in fish and shrimp by liquid chromatography-tandem mass spectrometry Jo, M.R., Southwest Sea Fisheries Research Institute, Yeosu, Republic of Korea; Lee, H.J., Southeast Sea Fisheries Research Institute, National Fisheries Research and Development Institute, Tongyeong, Republic of Korea; Lee, T.S., Southwest Sea Fisheries Research Institute, Yeosu, Republic of Korea ...
Food science and biotechnology,
06/2011, Letnik:
20, Številka:
3
Journal Article
Recenzirano
A sensitive and selective analytical method for 7 macrolides determination by LC-tandem mass spectrometry (LC-MS/MS) in fish and shrimp was developed. Samples were extracted by liquid-liquid ...extraction steps using 70% acetonitrile. The positive ionization produced the molecular related ions, (M+2H)²+, at m/z 422.3 for spiramycin I, and (M+H)+, at m/z 734.5, 772.4, 828.4, 837.4, 916.5, and 814.4 for erythromycin A, kitasamycin, josamycin, roxithromycin, tylosin A, and oleandomycin, respectively, were the precursor ions for collision-induced dissociation (CID) and 2 diagnostic product ions for each analyte were identified to carry out selected reaction monitoring (SRM) LC-MS/MS analyses. The recovery rates of macrolides in fish and shrimp samples were in the range 68.2-89.0, 72.8-91.6% and 75.2-87.0, 64.4-83.2% for the concentration of 50 and 100 ng/g, respectively.
Background: The present study evaluated the efficacy of a combination of ibandronate and cholecalciferol on the restoration of the levels of 25-hydroxyvitamin D (25OHD) and various bone markers in ...postmenopausal women with osteoporosis. Methods: This was a randomized, double-blind, active-controlled, prospective 16-week clinical trial conducted in 20 different hospitals. A total of 201 postmenopausal women with osteoporosis were assigned randomly to one of two groups: the IBN group, which received a once-monthly pill containing 150 mg ibandronate (n=99), or the IBN+ group, which received a once-monthly pill containing 150 mg ibandronate and 24,000 IU cholecalciferol (n=102). Serum levels of 25(OH)D, parathyroid hormone (PTH), and various bone markers were assessed at baseline and at the end of a 16-week treatment period. Results: After 16 weeks of treatment, the mean serum levels of 25(OH)D significantly increased from 21.0 to 25.3 ng/mL in the IBN+ group but significantly decreased from 20.6 to 17.4 ng/mL in the IBN group. Additionally, both groups exhibited signifi-cant increases in mean serum levels of PTH but significant decreases in serum levels of bone-specific alkaline phosphatase and C-telopeptide of type 1 collagen (CTX) at 16 weeks; no significant differences were observed between the groups. However, in subjects with a vitamin D deficiency, IBN+ treatment resulted in a significant decrease in serum CTX levels compared with IBN treatment. Conclusion: The present findings demonstrate that a once-monthly pill containing ibandronate and cholecalciferol may be useful for the amelioration of vitamin D deficiency in patients with postmenopausal osteoporosis. Moreover, this treatment combination effectively decreased serum levels of resorption markers, especially in subjects with a vitamin D deficiency, over the 16-week treatment period.
To secure the biological safety of live fish and shellfish for raw consumption, the germicidal effects of electrolyzed seawater were evaluated. Upon direct exposure to electrolyzed seawater, coliform ...group bacteria were killed and decreased to undetectable levels after 1 day. The physicochemical characteristics of the seawater were stable during the test period. A byproduct of chlorine disinfection, trihalomethane, was not generated by the electrolysis of seawater. Vibrio parahaemolyticus infection in a live fish was effectively resolved by electrolyzed seawater and became undetectable after 12-36 h of treatment. Bioaccumulation of coliform group and fecal coliform bacteria in live oysters Crassostrea gigas was removed within 18 h of treatment. This study demonstrated that electrolyzed seawater is an effective and safe germicidal agent for the traditional retail market and can help to prevent outbreaks of foodborne disease associated with the consumption of raw fish and shellfish.
수산생물 종류별 마비성 패류독소 축적 및 정화 목종수; Jong Soo Mok; 오은경 ...
한국수산과학회지,
10/2012, Letnik:
45, Številka:
5
Journal Article
Odprti dostop
To compare the accumulation of paralytic shellfish poison (PSP) in different marine organisms, the occurrence and vailation of PSP were surveyed in blue mussel Mytilus edulis, oysler Crassostrea ...gigas, short neck clam Ruditapes philip-pinarum, bay scallop Argopecten irradians, and warty sea squirt Stvela clava collected from Jinhae Bay, Korea, in 2005 and 2006 year. We also investigated the ability of the blue mussel to detoxify PSP by relaying and depuration (via the water flow or water circulation system). In the marine organisms examined, PSP levels were the highest in blue mussel, followed in order by bay scallop, oyster, short neck clam, and warty sea squirt. Comparing the maximum PSP levels in the bivalve species examined in 2005 and 2006, PSP in blue mussel was 1.6-2.0, 4.0-5.9, and 5.1-6.0 times higher than in bay scallop, oyster, and short neck clam, respectively. Therefore, blue mussel could be useful as a bioindicator for PSP monitoring. With the increasing PSP levels in blue mussel in 2006, the proportion of PSP in its digestive gland increased to 95.1% when the maximum level was detected from the whole tissues of blue mussel on May 29. Subsequently, the PSP proportion in the digestive gland decreased as the PSP level in whole tissue decreased, The detoxification of PSI` in blue mussel was greatest with relaying, followed by the water flow, and water circulation systems, Relaying decreased the PSP level below the regulatory limit of 80ug/100g after 2 days in low toxic sample with 124ug/l00g, and after 7 days in high toxic sample with 401 pg /100 g. During depuration in the blue mussel with 401ug/100g via the water how system, the PSP amounts in the digestive gland decreased by about 50% after I day, and about 77% after 7 days. In contrast, the PSP amounts in the soft body, gill, and mantle did not change significantly with depuration.
A sensitive and selective analytical method for 7 macrolides determination by LC-tandem mass spectrometry (LC-MS/MS) in fish and shrimp was developed. Samples were extracted by liquid-liquid ...extraction steps using 70% acetonitrile. The positive ionization produced the molecular related ions, $(M+2H)^{2+}$, at m/z 422.3 for spiramycin I, and $(M+H)^+$, at m/z 734.5, 772.4, 828.4, 837.4, 916.5, and 814.4 for erythromycin A, kitasamycin, josamycin, roxithromycin, tylosin A, and oleandomycin, respectively, were the precursor ions for collision-induced dissociation (CID) and 2 diagnostic product ions for each analyte were identified to carry out selected reaction monitoring (SRM) LC-MS/MS analyses. The recovery rates of macrolides in fish and shrimp samples were in the range 68.2-89.0, 72.8-91.6% and 75.2-87.0, 64.4-83.2% for the concentration of 50 and 100 ng/g, respectively.
An enzyme-linked immunosorbent assay (ELISA)-on-a-chip (EOC) biosensor combined with cell concentration technology based on immuno-magnetic separation (IMS) was investigated for use as a potential ...tool for early screening of Listeria monocytogenes (L. monocytogenes) in food products. The target analyte is a well-known pathogenic foodborne microorganism and outbreaks of the food poisoning typically occur due to contamination of normal food products. Thus, the aim of this study was to develop a rapid and reliable sensor that could be utilized on a daily basis to test food products for the presence of this pathogenic microorganism. The sensor was optimized to provide a high detection capability (e.g., 5.9 ${\times}\;10^3$ cells/mL) and, to eventually minimize cultivation time. The cell density was condensed using IMS prior to analysis. Since the concentration rate of IMS was greater than 100-fold, this combination resulted in a detection limit of 54 cells/mL. The EOC-IMS coupled analytical system was then applied to a real sample test of fish intestines. The system was able to detect L. monocytogenes at a concentration of 2.4 CFU/g after pre-enrichment for 6 h from the onset of cell cultivation. This may allow us to monitor the target analyte at a concentration less than 1 CFU/g within a 9 h-cultivation provided a doubling time of 40 min is typically maintained. Based on this estimation, the EOC-IMS system can screen and detect the presence of this microorganism in food products almost within working hours.
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