• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.21 no.1
• /
• pp.50-56
• /
• 1988

In order to fine some proper bacterial food for Tigriopus japoncus, bacterial flora of the tide pool inhabited by the copepod has been isolated and tested as bacterial food. Food effect and optimum density of the bacteria in terms of survival rate of the copepod was measured in the larval and the adult stages. Among the 264 strains of isolated bacteria, Acinetobacter spp. Moraxella, spp., Flavobacterium spp. and Pseudomonas spp. were certified as effective food for the copepod. According to the experimental results, Acinetobacter spp. AG-3 was the most effective food for all the stages from nauplius to adult, while Moraxella spp. and Flavobacterium spp. were effective for copepodite stage, and Pseudomonas spp. for the adult stage only. The optimum density of bacteria for the food was about $10^6\;cell/ml$, which was the same average density of bacteria in the tide pool.

• Korean journal of food and cookery science
• /
• v.12 no.3
• /
• pp.312-319
• /
• 1996

Oyster (Crassostrea virginica) and Weakfish (Cynoscion regalis) were stored at 6, 0, -4 and -20$^{\circ}C$ for up to 45 days and examined for changes in microflora. Aerobic plate counts (incubated at 21$^{\circ}C$) were performed at selected times during storage and 495 isolates (255 isolates from oyster and 240 isolates from Weakfish) were randomly selected from the plates during the storage. Before the storage of the fishes, viable counts of oyster were 4.9${\times}$10$\^$5/ CFU/g of meat and those of Weakfish were 1.5${\times}$10$^4$ CFU/cm$^2$of skin. Microflora of oyster before storage, the major isolates identified as Pseudomonas spp. (67%) and Vibrio spp. (20%). Pseudomonas ll1/1V-H and Flavobacterium/Cytophaga were predominant genus in the microflora of oyster during cold storage at 6, 0, -4 and -20$^{\circ}C$. The composition of the microflora of Weakfish before storage, Acinetobacter (40%) and Moraxella (33%) were the major species, with Pseudomonas and Vibrio constituting a small percentage of the total isolates. The microflora shifted to predominantly Pseudomonas spp. during storage at 6. 0 and -4$^{\circ}C$, making up from 60 to 100％ of isolated strains. During frozen storage, the percentage of isolates identified as Mnraxella increased to 40-60% of the total isolates. During cold storage, halophilic bacteria (Pseudomonas lII/IV-H and Vibrio) were predominant in oyster while nonhalophilic bacteria (Pseudomonas III/IV-NH and Moraxella) were predominant in Weakfish. Vibrio spp. were higher in oyster than in Weak fish. Listeria spp. were not isolated but unidentified ${\beta}$-hemolytic bacteria were islolated from both of the fishes during cold storage.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.23 no.1
• /
• pp.7-11
• /
• 1990

As the putrefaction of fish is greatly relied on the microorganisms inhabited in the viscera of them, we investigated the microfloral changes in the viscera of sardine, Sardinops melanosticta, which has been caught a lot in adjacent sea of Korea but showed rapid spoilage, after storages with various temperature. The following results were obtained. Viable cell counts at $25^{\circ}C$ of the viscera of sardine were $1.6\times10^5/g$ at the fresh sample, $1.5\times10^5/g$ at the frozen sample, $2.9\times10^8/g$ at the spoiled samples. The most predominant microbial genera from the fresh sardine were Moraxella spp.($31.4\%$) and Pseudomonas spp.($28.6\%$), but Enterobacteriaceae($83.1\%$) was in spoiled sample. While Moraxella spp.($46.2\%$) and Flavobacterium-Cytophaga($21.0\%$) were predominant in the frozen sample and Enterobacteriacear($69.6\%$) was in the thawed-spoiled sample. The rates of proteolytic enzyme producing bacteria were $20\%$ in the fresh sample, $22\%$ in the frozen sample but the rates were increased to $52\%,\;29\%$ in the spoiled sample and the thawed-spoiled sample respectively.

• Journal of fish pathology
• /
• v.13 no.1
• /
• pp.67-73
• /
• 2000

This study was carried out to elucidate the preliminary ecosystem of the heterotrophic bacterial flora in Kunsan Bay located in western costal area of Korea. Samples were collected at 5 sampling stations. Among 123 bacterial isolates, 9 genera of bacteria were appeared as follows; Vibrio spp.(44 isolates/35.7%), Pseudomonas spp.(42 isolates/34.1%), Aeromonas spp.(11 isolates/8.9%), Moraxella spp.(9 isolates/7.3%), Enterobacteria spp.(6 isolates/4.8%), Bordetella spp.(3 isolates/2.4%), Alkaligenesis spp.(3 isolates/2.4%), Flavobacterium spp.(2 isolates/1.6%), and Staphylococcus spp.(3 isolates/2.4%) respectively. Total viable heterotrophic bacteria was ranged from $5{\times}10^3$ to $1{\times}10^5$ CFU/ml and the most abundant viable counts of bacterial population were showed at the stations 2 and 3. This result indicates that the coastal area around Kunsan bay is getting to contaminate far more by municipal wastewaters and industrial byproducts. and so the outbreak of the bacterial diseases will be increased in fish farms.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.25 no.4
• /
• pp.314-321
• /
• 1992

To study the seasonal variation of heterotrophic bacteria on the blades of Porphyra species, samples were collected In the intertidal zone near Mokp'o of the Yellow Sea from February to December, 1990 Annual distribution of heterotrophic bacteria on the blades of Porphyra species ranged from $6.9\times10^2\;to\;1.04\times10^5\;cfu/cm^2$ at site 1, and from $9.4\times10^3\;to\;2.93\times10^5\;cfu/cm^2$ at site 2. Average sixty-five percent of isolates from the blades of Porphyra species were rods and $52.1-82.7\%$ of isolates were Gram-negative. Most isolates showed starch hydrolysis$(68\%)$ on March, but showed Poor utilization of carbon sources and no $H_2S$ production. Dominant genus isolated from the baldes of Porphyra species were Alcaligenes spp., Moraxella spp., on March and Micrococcus spp., Moraxella spp., Corynebacterium spp., on November.

• Applied Biological Chemistry
• /
• v.34 no.3
• /
• pp.279-286
• /
• 1991

In order to investigate the possibility of the microbial degradation of the persistent pollutant 3, 3', 4, 4'-tetrachloroazobenzene (TCAB) in our environment, four strains of microorganisms were isolated from industrial wastes by the enrichment technique. They were identified as Achromobacter group VD, Pseudomonas alcaligenes, Moraxella spp., and Alcaligenes faecalis, respectively. These microorganisms utilized TCAB as a sole carbon source in the $MM_2$ salt medium.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.25 no.4
• /
• pp.307-313
• /
• 1992

To study the seasonal variation of heterotrophic bacteria near the surrounding seawater of Porphyra forming area, samples were collected in the intertidal waters of Mokp'o of the Yellow Sea from February to December, 1990. Annual distribution of heterotrophic bacteria ranged from $7.5\times10^2\;to\;1.1\times10^5\;cfu/ml,$ annual distribution of physiological characteristic bacteria ranged from $5.0\times10\;to\;4.34\times10^4\;cfu/ml$ for proteolytic bacteria, from 0 to $1.35\times10^4\;cfu/ml$ for lipolytic bacteria and from 0 to $1.2\times10^4\;cfu/ml$ for amylolytic bacteria. Sixty-five percent of isolates from seawater were rods, and $76.7\%$ of isolates were Gram-negative. Most isolates were mesophiles and showed utilization of various carbon sources such as glucose, maltose, lactose, sucrose and arabinose. Most isolates also showed tolerance to a broad range of salt concentration. Dominant genus in seawater were Flavobacterium spp., in February, Moraxella spp., Acinetobacter spp. in March, Bacillus spp., Chromobacterium spp., Micrococcus spp., Vibrio spp. in July and Chromobacterium spp., Micrococcus spp., Bacillus spp. in November.

• Journal of fish pathology
• /
• v.13 no.2
• /
• pp.111-119
• /
• 2000

One hundred and twenty three strains of bacterial flora collected from Kunsan bay and examined for drug resistance to 9 antibiotics. The isolated and examined bacteria were Vibrio spp.(44 strains), Pseudomonas spp.(42 strains), Aeromonas spp.(26 strains), Moraxella spp.(9 strains), Enterobacteria spp.(6 strains), Bordetella spp.(3 strains), Alkaligenesis spp.(3 strains), Staphylococcus spp.(3 strains), and Flavobacterium spp.(2 strains). The drugs used were Ampicillin(AM), Penicillin-G(PM), Rifampicin(RF), Streptomycin(SM), Oxolinic acid (OA), Nalidixic acid(NA), Oxytetracycline(OT), Amikacin(AK), and Enorfloxacin(EF). Forty two strains were found to be sensitive to all drugs. The remaining strains showed resistance to various combinations of drugs. Among the resistant strains were mostly restricted to AM(54 strains/43.9%), PM(47 strains/38.2%), RF(35 strains/28.4%), SM(9 strains), OA(5 strains/ 4.06%), and NA(1 strains/0.8%), in combination at high degree showing 15 different drug resistant patterns. The most frequently showed resistant patterns were AM-PM-RF(16 strains/13.4%), AM-PM(8 strains/6.5%), and PM-RF(7 strains/5.6%). These results suggested that Kunsan bay were contaminated with various strains of highly resistant strains to drugs(AM, PM and RF). These results suggest that high levels of various antibiotics have already been introduced to Kunsan bay. Furthermore it seems that chemotherapy of fish disease has become extremely difficult because of the acquirement of multi-drug resistance to wide range of antibiotics.

• Journal of Korea Soil Environment Society
• /
• v.1 no.2
• /
• pp.35-42
• /
• 1996

Seawater samples were collected from P'ohang coastal area during April 1995 - January 1996. The distribution of total heterotrophic bacteria and crude oil-degrading bacteria (CDB) were studied. In addition, biodegradation of crude oil was investigated through mono and mixed culture. The heterotrophic bacterial distribution was in the range of 4.1 $\times$ $10^4$- 1.2 $\times$ $10^5$ CFU/$m\ell$, respectively. The percent of crude oil-degrading bacteria against total heterotrophic bacteria was 0.05-0.54% which was lower than other marine samples reported. Therefore it could be suggested that the distribution of crude oil-degrading bacteria in the seawater of P'ohang coastal area was highly affected by presence of petroleum hydrocarbon. Taxonomical characteristics of 26 isolates were investigated. The results of identification were showed 7 genera which were Acinetobacter spp., Bacillus spp., Citrobacter spp., Micrococcus spp., Moraxella spp., Rhodococcus spp., and Serratia spp. Appearance of Enterobacteriaceae indicated that the seawater was polluted with wastewater. Also genus of Bacillus had predominant in CDB on P'ohang coastal area. In flask culture, biodegradation of crude oil was enhanced by addition of mixed culture of CDB.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.18 no.1
• /
• pp.57-62
• /
• 1985

The three tide pools of Kanagawagen Aburatsubo coast, Japan were studied for 5 months (June-October, 1991) to know the physicochemical factors and changes of the microflora, In the tide pools salinity was ${\simeq}35\%0$, temperature range was $14{\sim}32^{\circ}C$ and pH range was $7.4{\sim}8.9$. Particulate organic carbon (POC) was $255{\sim}3980\;{\mu}g-at/l$, and total phosphate-P was $1.0{\sim}27.0\;{\mu}g-at/l$. The numbers of suspended bacteria and heterotrophic bacteria on the algae were $10^4{\sim}10^7/ml$ and $10^6{\sim}10^8/g$, respectively. Bacterial flora isolated from the Samples were Acinetobacter spp., Moraxella spp., Flavobacterium spp. and Pseudomonas spp., While Acinetobacter spp. was predominant among them. T. japonicus occurred dominantly with densities of $2200{\sim}7000/l$ during $August{\sim}september$. During this period the sharp increases of the unicellular microalgae and the protozoans were observed. According to the experimental results (POC, total phosphate-P, numbers and composition of bacterial flora), T. japonicus seemed to inhabit the environment with high eutrophication and high variability.