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Publications (8)14.22 Total impact

  • Article: Application of DNA Technique for Identifying the Species of Different Processed Products of Swordfish Meat
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    ABSTRACT: Polymerase chain reaction technology and sequence analysis were used to identify the species in fresh, frozen, cooked, sterilized, and dressed dried fried meat of swordfish Xiphias gladius. The specific primers L-HS I, II, III, and IV, in conjunction with H-CSBDH, produced 357-, 238-, 137-, and 87-bp fragments, respectively, in the control region of swordfish mitochondrial DNA, but not for other billfish. These fragments were useful for detecting the species used in processed products claiming to be X. gladius. The primers L-HS IV and H-CSBDH produced 87-bp mtDNA fragments to identify the species of dressed dried fried swordfish meat products. Using L-HS IV and H-CSBDH primers’gene fragment to judge, it was found that only 45.8% (11/24) commercial samples of dressed dried fried products were made from swordfish.
    Journal of Food Science 06/2008; 69(1):FCT1 - FCT6. · 1.66 Impact Factor
  • Article: Identification of Toxin and Fish Species in Cooked Fish Liver Implicated in Food Poisoning
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    ABSTRACT: The cooked fish liver retained by the victims was assayed for toxicity and mitochondrial DNA. Meanwhile, 8 live specimens of puffer Takifugu niphobles were also assayed. The toxicity of cooked fish liver was 280 ± 20 mouse units per gram (MU/g). All specimens of T. niphobles showed high toxicity (more than 850 MU/g) in the liver. The toxin from cooked fish liver and liver of T. niphobles was identified to be tetrodotoxin. The cooked fish liver and fresh liver of T. niphobles showed the same sequence genotype and the same single restriction site for Bsa I. Therefore, the species of cooked fish liver was suggested as T. niphobles.
    Journal of Food Science 07/2006; 67(3):948 - 952. · 1.66 Impact Factor
  • Article: Determination of tetrodotoxin in human urine and blood using C18 cartridge column, ultrafiltration and LC-MS.
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    ABSTRACT: Six fishermen were victims (including one death) of food poisoning from unknown fish on their boat in central Taiwan Strait, in April 2001. The symptoms were like those of tetrodotoxin (TTX) poisoning. As there was no remaining fish, a new protocol was developed to determine TTX in the urine and blood of the victims. The urine and blood samples were cleansed using a C18 Sep-Pak cartridge column, and the toxin was extracted by methanol. The eluate was filtered through a microcentrifuge filter. The filtrate was freeze-dried, dissolved in distilled water, and determined by LC-MS. The recovery was more than 88.9%. The detection limit was 15.6 nM. A linear relationship between response and concentration was obtained between 93.75 and 9375 nM of TTX. It was shown that the urine and blood of the victims contained TTX. The range of TTX was 4.5-40.6 nM in blood and 47-344 nM in urine. Judging from the symptoms of the victims and the experimental data, the causative agent of the food poisoning was identified as TTX.
    Journal of Chromatography B 03/2006; 832(1):75-80. · 2.89 Impact Factor
  • Article: Microflora and tetrodotoxin-producing bacteria in a gastropod, Niotha clathrata.
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    ABSTRACT: Shellfish (Niotha clathrata) were collected in both July and November from three locations in Taiwan (Pingtung, Kaohsiung and Chiai Prefecture) and assayed for anatomical distribution of tetrodotoxin (TTX) and aerobic heterotrophic bacteria. Pingtung specimens showed higher toxicity than those from Kaohsiung and Chiai, and did not show much seasonal variation. At each site, the total aerobic bacterial counts in November samples were higher than in July. The predominant genera were Vibrio, Pseudomonas, Pasteurella, Aeromonas and Plesiomonas. Vibrio comprised more than 35% of the genera, with V. alginolyticus as the major species. The viable counts of Vibrio species were higher in November than in July. However, the results did not suggest any relationship between the total count or viable count and the toxicity of the shellfish. HPLC, UV and gas chromatographic-mass spectrometric analyses demonstrated that some of the bacteria isolated, such as V. alginolyticus, V. parahaemolyticus, Pseudomonas spp. Plesiomonas sp. and Aeromonas sp., produced TTX and/or related substances.
    Food and Chemical Toxicology 12/1995; 33(11):929-34. · 3.00 Impact Factor
  • Article: Gonyautoxin-3 as a minor toxin in the gastropod Niotha clathrata in Taiwan.
    D F Hwang, C A Cheng, S S Jeng
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    ABSTRACT: Paralytic toxicity was detected in the gastropod mollusc Niotha clathrata collected from South Taiwan in April and November 1993. Each seasonal toxin was partially purified from toxic specimens of N. clathrata by ultrafiltration using a membrane (Diaflo YM-2), followed by chromatography on a column (Bio-Gel P-2). Two toxin fractions (I and II) were then obtained for each seasonal shell toxin. The ratio of fraction I to fraction II for each seasonal shell toxin was about 4:1 according to tetrodotoxin bioassay. Based on analyses by TLC, electrophoresis, and HPLC, fraction I toxin contained tetrodotoxin and its derivative anhydrotetrodotoxin, and fraction II toxin contained gonyautoxin-3 for each seasonal shell toxin.
    Toxicon 01/1995; 32(12):1573-9. · 2.51 Impact Factor
  • Article: Comparison of paralytic toxins in aquaculture of purple clam in Taiwan.
    D F Hwang, Y H Tsai, C A Cheng, S S Jeng
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    ABSTRACT: Food poisoning incidents due to ingesting the cultured purple clam Soletellina diphos occurred in western Taiwan in February 1991. Clam specimens, sediment and the dinoflagellate Alexandrium tamarensis were collected and assayed for lethality as paralytic shellfish poison (PSP). The lethality of purple clam, wet sediment and phytoplankton was 1700 mouse units per specimen (MU/specimen), 0.05 MU/g and 3.6 x 10(-5) MU/cell, respectively. The toxins obtained from clam, sediment and phytoplankton consisted of gonyautoxins 1-4, along with trace amounts of neosaxitoxin.
    Toxicon 30(5-6):669-72. · 2.51 Impact Factor
  • Article: Microflora and tetrodotoxin-producing bacteria in a gastropod, Niotha clathrata
    [show abstract] [hide abstract]
    ABSTRACT: Shellfish (Niotha clathrata) were collected in both July and November from three locations in Taiwan (Pingtung, Kaohsiung and Chiai Prefecture) and assayed for anatomical distribution of tetrodotoxin (TTX) and aerobic heterotrophic bacteria. Pingtung specimens showed higher toxicity than those from Kaohsiung and Chiai, and did not show much seasonal variation. At each site, the total aerobic bacterial counts in November samples were higher than in July. The predominant genera were Vibrio, Pseudomonas, Pasteurella, Aeromonas and Plesiomonas. Vibrio comprised more than 35% of the genera, with V. alginolyticus as the major species. The viable counts of Vibrio species were higher in November than in July. However, the results did not suggest any relationship between the total count or viable count and the toxicity of the shellfish. HPLC, UV and gas chromatographic-mass spectrometric analyses demonstrated that some of the bacteria isolated, such as V. alginolyticus, V. parahaemolyticus, Pseudomonas spp., Plesiomonas sp. and Aeromonas sp., produced TTX and/or related substances.
    Food and Chemical Toxicology.
  • Article: Determination of tetrodotoxin in human urine and blood using C18 cartridge column, ultrafiltration and LC–MS
    [show abstract] [hide abstract]
    ABSTRACT: Six fishermen were victims (including one death) of food poisoning from unknown fish on their boat in central Taiwan Strait, in April 2001. The symptoms were like those of tetrodotoxin (TTX) poisoning. As there was no remaining fish, a new protocol was developed to determine TTX in the urine and blood of the victims. The urine and blood samples were cleansed using a C18 Sep-Pak cartridge column, and the toxin was extracted by methanol. The eluate was filtered through a microcentrifuge filter. The filtrate was freeze-dried, dissolved in distilled water, and determined by LC–MS. The recovery was more than 88.9%. The detection limit was 15.6 nM. A linear relationship between response and concentration was obtained between 93.75 and 9375 nM of TTX. It was shown that the urine and blood of the victims contained TTX. The range of TTX was 4.5–40.6 nM in blood and 47–344 nM in urine. Judging from the symptoms of the victims and the experimental data, the causative agent of the food poisoning was identified as TTX.
    Journal of Chromatography B.