• Journal of Life Science
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• v.13 no.4
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• pp.390-399
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• 2003

Four species of the genus of Listeria were isolated from seawater and sea food in Kyungnam province, South Korea. These isolated strains were classified into Listeria sp. from different samples by appropriate cultivation conditions and biochemical tests including serological test. In a day enrichment cultivation, the following strains were found out of 100 samples: L. innocua (35%), L. ivanovii (4%), L. monocytogenes (4%), and L. welshimeri (1%). For seven days enrichment culture, L. innocua (38%), L. ivanoii (5%), L. monocytogenes (7%), and L. welshimeri (1%) were isolated. From these results, Listeria species were more efficiently isolated in seven day enrichment broth than in one day enrichment. However, these isolated Listeria species were less grown in the selective medium than in the enrichment medium. Isolation rates of Listeria species showed differency for each sample and Listeria species were more abundantly isolated in shrimps (80%) and crayfishes (80%) than little neck clams (50%), seawater (25%) and mussels (20%). From the results of serological classes for the seven L. monocytogenes, two strains were defined as type I and the other five strains as type IV.

• Journal of Nutrition and Health
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• v.45 no.1
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• pp.94-102
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• 2012

There is a limitation to estimate vitamin $B_{12}$ intake due to a lack of data on vitamin $B_{12}$ content in many Korean foods. In this study, vitamin $B_{12}$ content was determined in some seaweeds, fish, and shellfish and their product that are consumed in Korea using a modified microbioassay with Lactobacillus delbruecki ATCC 7830. Dried laver and dried seasoned and toasted laver contained very high levels of vitamin $B_{12}$ (66.8 and $55.2-71.3\;{\mu}g$/100 g, respectively. Sea lettuce and seaweed fulvescene also contained high vitamin $B_{12}$ content of 5.47-9.41 and $6.46-7.20\;{\mu}g$/100 g, respectively, whereas sea mustard and sea tangle contained low levels of vitamin $B_{12}$; vitamin $B_{12}$ was not detected in seaweed fusifome. Pacific saury, trout, sea-bass, or squid contained 12.01, 2.00, 0.49 and $2.33\;{\mu}g$ vitamin $B_{12}$/100 g, respectively. Ochellatus octopus, and naked sand lance contained 0.72-1.43 and $3.68\;{\mu}g$ vitamin $B_{12}$/100 g, respectively. Dried Alaska pollack con-tained $0.19-2.64\;{\mu}g$ vitamin $B_{12}$/100 g. Shellfish such as little neck clam and small ark shellfish contained high levels of vitamin $B_{12}$ of $30.5-40.5\;{\mu}g$/100 g, and mussel and abalone contained 17.71 and $7.82\;{\mu}g$/100 g, respectively. Of unique Korean traditional fermented seafood products, salt-fermented products of squid ($2.91\;{\mu}g$/100 g), clams ($34.31\;{\mu}g$/100 g), Ala-ska pollack roe ($9.98-12.02\;{\mu}g$/100 g), hairtail guts ($4.58\;{\mu}g$/100 g) or small shrimp ($0.58-1.55\;{\mu}g$/100 g), and fish sauce from anchovies ($1.52-1.78\;{\mu}g$/100 mL), sand eel ($0.22-0.24\;{\mu}g$/100 mL) or small shrimp ($0.19-0.78\;{\mu}g$/100 mL) were analyzed. A few commercial brands of flying fish roe ($0.73-1.73\;{\mu}g$/100 g), canned tuna ($0.40\;{\mu}g$/100 g), and fried fish paste ($0.25-0.69\;{\mu}g$/100 g) were also analyzed. In conclusion, vitamin $B_{12}$ content in these foods, chosen considering the Korean food culture, should contribute to improve the present vitamin $B_{12}$ food database. It may be helpful to estimate vitamin $B_{12}$ intake more correctly than before, and provide additional information for dietary education related to vitamin $B_{12}$ and meal management.

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