• Journal of Microbiology
• /
• 제42권2호
• /
• pp.74-79
• /
• 2004

Ingestion of shellfish-associated Vibrio parahaemolyticus is the primary cause of potentially severe gas-troenteritis in many countries. However, only Kanagawa phenomenon (hemolysin) positive (KP$\^$+/) strains of V. parahaemolyticus are isolated from patients, whereas >99％ of strains isolated from the environment do not produce this hemolysin (i.e. are KP$\^$-/). The reasons for these differences are not known. Following a temperature downshift, Vibrio parahaemolyticus enters the viable but noncultur-able (VBNC) state wherein cells maintain viability but cannot be cultured on routine microbiological media. We speculated that KP$\^$+/ and KP$\^$-/ strains may respond differently to the temperature and salinity conditions of seawater by entering into this state which might account for the low numbers of cul-turable KP$\^$+/ strains isolated from estuarine waters. The response of eleven KP$\^$+/ and KP$\^$-/ strains of V. parahaemolyticus following exposure to a nutrient and temperature downshift in different salinities, similar to conditions encountered in their environment, was examined. The strains included those from which the KP$\^$+/ genes had been selectively removed or added. Our results indicated that the ability to produce hemolysin did not affect entrance into the VBNC state. Further, VBNC cells of both biotypes could be restored to the culturable state following an overnight temperature upshift.

• Fisheries and Aquatic Sciences
• /
• 제25권8호
• /
• pp.429-440
• /
• 2022

This study assessed the effects of oxygen and ozone nanobubbles on gill morphology, weight gain, and mortality of Pacific white shrimp (Penaeus vannamei), as well as the level of Vibrio parahaemolyticus and water quality of shrimp culture tanks under lab conditions. Two experiments were carried out with oxygen macrobubble, ozone macrobubble, oxygen nanobubble, ozone nanobubble, and control treatments (air-stone macrobubble). Experiments were done in triplicate in 100 L tanks with 15‰ saline water, and 20 shrimp per tank. Tanks in Experiment 1 were not inoculated with bacteria; tanks in Experiment 2 were inoculated with V. parahaemolyticus at a concentration of 10⁶ CFU/mL. The results revealed that short treatments with ozone nanobubbles had minimal impact on shrimp gills, mortality, and growth rates, reduced V. parahaemolyticus concentration in water compared to the other groups, and improve water quality. These laboratory results indicate that ozone nanobubble treatment may be useful for controlling V. parahaemolyticus. More work is needed to find the best protocol to apply the technology on a commercial scale.

• 한국수산과학회지
• /
• 제47권5호
• /
• pp.508-515
• /
• 2014

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 antimicrobial 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.

• 한국수산과학회지
• /
• 제49권4호
• /
• pp.460-466
• /
• 2016

From 2013 through 2015, we investigated the contamination status and antimicrobial resistance patterns of pathogenic Vibrio parahaemolyticus in commercially valuable seawater and shellfish (Oyster Crassostrea gigas, short-neck clam Venerupis philippinarum, ark shell Scapharca broughtonii and mussel Mytilus galloprovinciallis) from the southern coast of Korea. The detection rate of V. parahaemolyticus was highest in short-neck clams (23.7%), followed by ark shells (19.2%), oysters (15.9%), mussels (13.6%), and seawater (8.6%). The following percentages of PCR assays of shellfish were positive for the thermostable direct hemolysin-related hemolysin gene (trh) : oysters (12.8%), short-neck clams(11.8%), and ark shells (3.4%). Similar assays for the thermostable direct hemolysin gene (tdh) resulted in positive results for short-neck clams (5.9%) and ark shells (3.4%). Antimicrobial resistance was present in 100% of 8 tdh (+) and 2 trh (+) V. parahaemolyticus isolates challenged with ampicillin. However, all pathogenic V. parahaemolyticus were sensitive to 14 other antibiotics. To ensure the safety of shellfish consumption, the continuous monitoring of the prevalence and distribution of virulence factors of V. parahaemolyticus in shellfish farms is needed.

• 한국수산과학회지
• /
• 제50권6호
• /
• pp.662-668
• /
• 2017

This study investigated the antimicrobial resistance patterns of Escherichia coli and Vibrio parahaemolyticus isolated from oysters Crassostrea gigas, short-necked clams Ruditapes philippinarum and corb shells Cyclina sinensis from the West Coast of Korea from June through November 2013. The antimicrobial susceptibility patterns of the isolated strains of E. coli and V. parahaemolyticus to 12 antimicrobial agents used in Korea for clinical or veterinary therapy were analyzed. Antimicrobial resistance to at least one antibiotic was seen in 52.0% of the E. coli isolates (156 strains) and 44.3% of the V. parahaemolyticus isolates (194 strains). The resistance of the E. coli (34.0%) and V. parahaemolyticus (41.8%) isolates to ampicillin was highest. Multiple antimicrobial resistance against at least three antimicrobials was seen in 9.0% of the E. coli isolates and 1.0% of the V. parahaemolyticus isolates.

• 한국식품영양과학회지
• /
• 제32권8호
• /
• pp.1351-1356
• /
• 2003

배추김치의 항균작용을 실험한 본 연구에서 1개월간 발효된 배추김치즙 시료(염분 2.8%, 산도 1.34%, PH 4.1)를 2% 함유한 보통 한천 배지에서 실험군의 집락수 억제율은Salmonella enteritidis ATCC 13076이 가장 낮은 63%이었고 Enterobacter cloacae ATCC 13047과 Staphylococcus aureus ATCC 6538p은 각각 72%, 76%이었고 Vibrio parahaemolyticus ATCC 17802은 가장 높은 90%를 보였다. Vibrio parahaemolyticus ATCC 17802는 배추김치즙 함량이 6%에서 100%발육 억제효과를 보여 실험균 중 배추김치즙에 대한 저항력이 가장 약했으나 동일한 배추김치즙 시료농도(6%)에서 Salmonella enteritidis ATCC 13076, Enterobacter cloacae ATCC 13047, Staphylococcus aureus ATCC 6538p는 각각 89%, 90%, 91% 의 집락수 억제 효과를 보였다. 배추김치즙 함량 10%에서 모든 실험군의 집락가100% 억제되는 효과를 보였다. 실험결과 1개월간 충분히 발효된 배추김치에는 어떤 식중독균도 생존할 수 없을 것으로 밝혀졌다.

• Fisheries and Aquatic Sciences
• /
• 제25권9호
• /
• pp.463-472
• /
• 2022

In this study, a microbial risk assessment was performed for the bacteria Vibrio parahaemolyticus, which causes a foodborne illness following the consumption of Jeotgal, a fermented seafood in South Korea. The assessment comprised of six stages: product, market, home, consumption, dose-response, and risk. The initial contamination level (IC) was calculated based on the prevalence of V. parahaemolyticus in 90 Jeotgal samples. The kinetic behavior of V. parahaemolyticus was described using predictive models. The data on transportation conditions from manufacturer to market and home were collected through personal communication and from previous studies. Data for the Jeotgal consumption status were obtained, and an appropriate probability distribution was established. The simulation models responding to the scenario were analyzed using the @RISK program. The IC of V. parahaemolyticus was estimated using beta distribution [Beta (1, 91)]. The cell counts during transportation were estimated using Weibull and polynomial models [δ = 1 / (0.0718 - 0.0097 × T + 0.0005 × T²)], while the probability distributions for time and temperature were estimated using Pert, Weibull, Uniform, and LogLogistic distributions. Daily average consumption amounts were assessed using the Pareto distribution [0.60284,1.32,Risk Truncate(0,155)]. The results indicated that the risk of V. parahaemolyticus infection through Jeotgal consumption is low in South Korea.

• 동아시아식생활학회지
• /
• 제20권6호
• /
• pp.881-887
• /
• 2010

천연식품 보존제의 개발과 이용에 대한 기초 자료를 확보하고자 31종의 한약재 추출물 중 S. aureus와 V. parahaemolyticus 등 식중독 유발균에 대해 우수한 항균 활성을 가지는 한약재를 선발하고, 선발된 한약재 추출물의 농도나 분획물의 항균 활성 등을 검토한 결과는 다음과 같다. 물과 메틸알콜을 용매로 추출하여 S. aureus와 V. parahaemolyticus에 대한 항균 활성을 조사한 결과, 지유, 황련 및 마치현 등이 강한 항균 활성을 가지며, 물보다는 메틸알콜 추출액의 항균 활성이 높은 것으로 나타났다. 특히 지유의 물 및 메틸알콜 추출물 모두 S. aureus 및 V. parahaemolyticus에 대하여 강한 항균 활성이 있었다. 지유 추출물은 S. aureus에 대해서는 5% 희석 농도까지 항균 활성이 인정되었으나, V. parahaemolyticus에 대해서는 10% 희석 농도까지 항균 활성이 인정되었다. 지유 추출물의 EtOAc, BuOH 및 $H_2O$ 분획물은 S. aureus와 V. parahaemolyticus에 대하여 항균 활성이 있었으며, S. aureus에 대해서는 EtOAc 분획물은 5%, BuOH 분획물은 2% 그리고 $H_2O$ 분획물은 1% 희석 농도까지 항균 활성이 인정되었으며, V. parahaemolyticus에 대해서는 EtOAc 분획물은 1% 희석 농도, $H_2O$ 분획물은 2% 그리고 BuOH 분획물은 5% 희석 농도까지 항균 활성이 있는 것으로 나타났다.

• 한국식품위생안전성학회지
• /
• 제38권4호
• /
• pp.246-254
• /
• 2023

장염비브리오균은 급성 설사와 같이 수인성·식품매개 질병을 일으키는 것으로 알려져 있다. 본 연구에서는 제주지역 해수, 수족관수, 유통 수산물에서 분리한 장염비브리오균을 real-time PCR을 이용하여 잠재적인 독소 유전자 또는 종특이성 유전자(tdh, trh, tlh, toxR)를 조사하고, 이 균주의 유전적인 특성을 PFGE로 분석하였다. 총 245개 시료 중 해수에서 33주, 수족관수에서 7주, 수산물에서 50주로 90주(36.7%)의 장염비브리오균을 분리하였다. 모든 장염비브리오균에서 tdh 유전자는 검출되지 않았지만, tlh 유전자 또는 toxR 유전자는 검출되었다. 또한, 해수에서 3주와 수산물에서 1주 분리된 균주에서 trh 유전자가 검출되었다. 매달 해수를 정량검사한 결과 장염비브리오균은 수온과 양의 상관관계를 가지고 있었다. 90주의 장염비브리오균은 64.0-97.3% 범위에서 유사한 유전자 상동성을 보였다. 이중에서 13개 유형에서 유전자 상동성이 100%였다. 이러한 결과는 일부 독소 유전자를 가진 장염비브리오균이 분리되었고, 해수, 수족관물, 유통 수산물에서 분리된 장염비브리오균 사이에 유전적 유사성이 있기 때문에 식중독 역학조사에 도움이 되도록 지속적인 모니터링이 필요함을 나타낸다.

• 대한미생물학회지
• /
• 제22권1호
• /
• pp.61-70
• /
• 1987

Authors have isolated phages of V. parahaemolyticus from shellfish and investigated some of their characteristics. The results obtained were as follows: Twenty-three phage strains(9.2%) out of 250 specimens were isolated. Plaques of phages were small, clear or turbid and $0.5{\sim}1.5mm$ in diameter. The electron micrographs of K3 phages showed two morphology; one was a hexagonal head about 105nm with a tail about 12nm, the other was a hexagonnal head about 60nm with a tail about 25nm. The host ranges of pahges were limited to V. parahaemolyticus strains and there appeared to be no relationship between the K serotypes of V. parahaemolyticus strains and the host ranges of the phage isolates. The adsorption rate of phages were more than 80% for $10{\sim}15$ minutes, the inactivation rate at $60^{\circ}C$ was more than 99% for $40{\sim}45$ minutes. The pH stability range was between 6.0 and 8.0. The inactivation rate of phages by UV irradiation was more than 99% for $45{\sim}75$ seconds.