• 한국식품영양학회지
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• 제18권1호
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• pp.81-87
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• 2005

본 연구에서는 식중독 유발 세균에 대한 항균 활성이 우수한 천연 항균성 물질을 검색하기 위해 예로부터 민간과 한방에서 널리 이용되어온 황련을 각종 유기용매로 추출하여 식중독 유발 세균에 대한 항균 활성을 조사해 보았다. 황련을 petroleum ether, chloroform, ethyl acetate, methanol를 이용하여 실온에서 각각 용매별로 계통 분획하고, 열수추출물을 얻은 후, 9종의 식중독 유발세균(Staphylococcus aureus, Bacillus cereus, Salmonella enteritidis, Shigella flexneri, Escherichia coli, Salmonella typhimurium, Shigella dysenteriae, Pseudomonas aruginosa, Shigella sonnei)에 대하여 항균효과를 조사하였다. 황련 추출물의 농도별 항균 활성 검색에서는 황련의 methanol 추출물이 가장 큰 항균효과를 보였으며 S. aureus와 E. coli가 가장 민감하게 반응하는 균주였다. 황련의 methanol 추출물과 백화사설초의 methanol 추출물을 혼합하여 항균력을 측정해 본 결과 두 추출물을 섞어 첨가했을 경우가 단독으로 사용했을 시 보다 상승효과를 나타내었다. 또한 황련의 methanol 추출물이 식중독 유발세균의 성장에 미치는 효과를 검정하기 위해 S. aureus 및 E. coli의 배양액에 황련의 methanol 추출물을 각각 4,000 ppm 농도로 첨가했을 시, E. coli이 생육이 60시간 이상까지 억제됨을 관찰할 수 있었고, S. aureus의 생육도 36시간까지 지연시킬 수 있었다. 이상의 결과 황련의 methanol 추출물은 S. aureus와 E. coli이 성장을 효과적으로 억제시킬 수 있음을 알 수 있었다.

• 한국환경농학회지
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• 제30권4호
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• pp.459-465
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• 2011

BACKGROUND: Nowadays, Chemical antiseptics have become great problems for health and environmental, so that developing of new substitutes for chemical antiseptics is more and more important. Natural product is a kind of environment-friendly additive that could be used as antiseptic in food industry. Thuja orientalis cv Aurea Nana is a gymnospermous plant of the family Cupressaceae, native to northwestern China and widely naturalised elsewhere in Korea and Japan. This study was aimed to investigate the antibacterial potential of various organic extracts from T. orientalis cones against some food-borne and food-spoilage bacteria. METHODS AND RESULTS: Hexane extract (HE), chloroform extract (CE), ethyl acetate extract (EAE) and methanol extract (ME) were obtained from female cones of T. orientalis. The antibacterial activities of various extracts were tested by standard agar diffusion and minimum inhibitory concentrations (MICs) against five gram-positive and six gram-negative bacteria. Cell viability and morphology change of L. monocytogenes ATCC 10943 treated with hexane extract were also observed. The various extracts displayed remarkable antibacterial effects against all the gram-positive bacteria but did not show any effect against the gram-negative bacteria. Hexane extract has the highest inhibitory effect on cell viability of L. monocytogenes ATCC 10943. SEM observation also demonstrated the damaging effect of the hexane extract on the morphology of L. monocytogenes ATCC 10943 at the minimum inhibitory concentration. CONCLUSION(s): The tested gram-positive bacteria were significantly inhibited by organic extracts of T. orientalis cone. Hexane extract was the most potent against Listeria monocytogenes ATCC 10943, as evidenced by the lowest MIC level and the complete inhibition of cell viability within shortest exposure time, along with SEM observation.

• 식물병연구
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• 제26권2호
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• pp.88-94
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• 2020

Recently, the severe dieback of apple trees resulting from soil-borne diseases has occurred in South Korea. The casual agents of dieback were surveyed on 74 apple orchards that had been damaged nationwide in 2016-2019. The number of apple orchards affected alone by Phytophthora rot, violet root rot, and white root rot was 31, 34, and 3, respectively. Also, the total number of mixed infection orchards was 6. Out of 9,112 apple trees affected by dieback, the trees damaged by Phytophthora rot, violet root rot, and white root rot were 3,332, 3,831, and 44, respectively. Moreover, the total number of mixed infection apple trees was 1,905. The provinces mainly affected were Gyeongnam, Gyeongbuk, Chungbuk, and Jeonbuk. The survey on these infected apple orchards will be available to form management strategy for the dieback that had been increased by soil-borne fungal pathogens.

• The Plant Pathology Journal
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• 제35권2호
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• pp.156-163
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• 2019

Our study investigated the available chlorine content, contact time and difference among strains of each pathogen for sodium hypochlorite (NaOCl) to control chemically against soil-borne fungal pathogens, such as Phytophthora rot by Phytophthora cactorum, violet root rot by Helicobasidium mompa, and white root rot by Rosellinia necatrix, causing die-back symptom on apple trees. As a result, the colony growth of Phytophthora cactorum was inhibited completely by soaking over 5 s in 31.25 ml/l available chlorine content of NaOCl. Those of H. mompa and R. necatrix were inhibited entirely by soaking over 160 s in 62.5 and 125 ml/l available chlorine content in NaOCl, respectively. Also, inhibition effect on available chlorine in NaOCl among strains of each soil-borne pathogen showed no significant difference and was similar to or better than that of fungicides.

• Preventive Nutrition and Food Science
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• 제16권4호
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• pp.376-380
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• 2011

We investigated the total phenolic and flavonoid contents and the antimicrobial activity of ethanol extracts obtained from Saussurea lappa C.B. Clarke. The ethanol extracts of S. lappa C.B. Clarke were fractionated with various solvents (n-hexane, chloroform, and n-butanol). The antimicrobial activity of S. lappa C.B. Clarke was examined by disc-diffusion and micro-dilution susceptibility assays with six food-borne pathogens, and compared to that of the synthetic antibiotics. It is found that the S. lappa C.B. Clarke ethanol extract and n-hexane fraction have strong activity against B. cereus and V. parahaemolyticus strains compared to ampicillin. The inhibitory concentration ($IC_{50}$) values of hexane fraction against L. monocytogenes, B. cereus, and B. subtilis were 62.5, 250 and 500 ppm, respectively. Therefore, these data suggest that S. lappa C.B. Clarke may be useful as antimicrobial agents against food-borne pathogens.

• Food Science and Biotechnology
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• 제17권6호
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• pp.1345-1348
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• 2008

Titanium dioxide ($TiO_2$) shows antibacterial effects when exposed to near ultra violet (UV) light. In this study, $TiO_2$ photocatalytic continuous reactor was designed and applied to food-borne pathogens such as Vibrio parahaemolyticus ATCC 17802, Salmonella choleraesuis ATCC 14028, and Listeria monocytogenes ATCC 15313. $TiO_2$ films were prepared by conventional sol-gel dip-coating method using titanium tetra iso-propoxide (TTIP). The antibacterial activity of photocatalytic reactor with various flow rates and UV-A illumination time showed effective bactericidal activity. As the UV-A illumination time increased, survival rates of those bacteria decreased. After 60 min of UV-A illumination, the survival rates of V. parahaemolyticus and S. choleraesuis were less than 0.1%. However, that of L. monocytogenes was about 5% at that time point. These results present an effective way to exclude pathogenic bacteria from aqueous foods.

• 한국환경보건학회지
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• 제46권2호
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• pp.184-191
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• 2020

Objectives: This study was performed to analyze cases of food poisoning outbreaks reported in Chungcheongnamdo Province in 2019 and report it as effective data for preventing food poisoning in the future. Methods: Food poisoning outbreaks were analyzed to detect virus, bacteria, and protozoa according to the Manual for Detection of Foodborne Pathogens in Outbreaks to clarify the causes of food poisoning that occurred in Chungcheongnam-do Province in 2019. Results: Among the 79 cases of food poisoning outbreaks, 59 cases (74.7%) were in general restaurants, 15 cases (19.0%) in food service institutions, three cases at banquets, and two cases in take-out food. The 42 cases at general seafood restaurants made up the majority of food poisoning in Chungcheongnam-do. Food poisoning pathogens were shown in 13 cases (86.7%) out of the 15 cases at food service institutions, and 10 cases were related to Norovirus. Among the 79 cases, food-borne pathogens were identified in 35 cases of outbreaks, accounting for 44.3%. The confirmed pathogens were as follows: bacteria (24 cases), Norovirus (12 cases) and Kudoa septempunctata. (five cases). The food-borne bacteria were pathogenic E. coli (12 cases), Staphylococcus aureus (six cases), Salmonella spp. (two cases), Campylobacter jejuni, Bacillus cereus, Clostridium perfringens, and Vibrio parahaemolyticus (one case). Conclusions: To prevent food poisoning, it is necessary to analyze regional characteristics and environments and to hold a campaign for the prevention of food poisoning based on that analysis. In addition, when food poisoning occurs, the results of analyzing its cause and spread based on accurate epidemiological survey need to be shared.

• Journal of Microbiology and Biotechnology
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• 제6권6호
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• pp.461-467
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• 1996

Four strains of lactic acid bacteria (LAB), that lower the pH of sausage $\leq$ 4.2 within 24 h of incubation at $37^{\circ}C$, were screened from 57 bacteriocin producing LAB which were isolated from kajamie shikhae and natural fermented sausages. The proteinaceous nature of the bacteriocin was confirmed by losing antimicrobial activity after pronase treatment. Inhibitory activity against pathogens, times of bacteriocin production and sensory tests were compared between 4 isolates and 3 commercial starters. Especially, strain NFS #8-1, screened from natural fermented sausage and identified as Pediococcus acidilactici, antagonized a large number of foodborne pathogens including Listeria monocytogenes, Aeromonas hydrophila, Bacillus cereus, Clostridium perfringens, Salmonella typhimurium and Staphylococcus aureus. Production of bacteriocin by strain NFS #8-1 was early in the growth phase (mid log phase) and its sensory acceptance was high. The feasibility of using strain NFS #8-1 as a starter for the production of microbiologically safe fermented sausage is envisaged.

• 한국식품위생안전성학회지
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• 제26권2호
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• pp.114-119
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• 2011

본 연구에서는 신선편의 채소와 과일에서 주로 검출되는 대장균(E. coli Ol577:H7), 리스테리아(L. monocytogenes), 살모넬라(Salmonella, spp.), 형색포도상구균(S. aureus)을 검출하고 동정할 수 있는 real time PCR 방법을 melting curve 분석을 활용하여 single tube 반응으로 두 종의 식중독균을 동시 검출하는 방법을 개발하고자 하였다. 대장균의 ${\beta}$-glucuronidase (uidA), 황색포도상구균의 thermonuclease (nuc), 리스테리아의 hemolycin (hly), 살모넬라의 tetrahionate reductase (ttr) 를 특이적으로 검출할 수 있는 4종의 프라이머 세트에 대한 real-time PCR의 melting curve 분석을 통하여 황색포도상구균과 대장균 동시분석 시 $T_m$ 값이 $80.6{\pm}0.9^{\circ}C$와 $86.9{\pm}0.5^{\circ}C$, 리스테리아와 살모넬라 동시분석 시 Tm 값이 $80.4{\pm}0.6^{\circ}C$와 $88.1{\pm}0.11^{\circ}C$로 확인하였고, 그 결과 정제되어진 각 식중독균의 genomic DNA를 주형으로 한 duplex real-time PCR 방법이 uniplex real-time PCR 방법과 마찬가지로 10 genome equivalents 까지 검출할 수 있는 민감도를 나타내었다. 또한, 양배추에 네 종의 식중독균을 접종하고, 증균배양 없이 DNA를 추출하여 duplex real-time PCR 을 수행한 결과 모든 식종목균에서 $10^3$ CFU/g의 검출 한계를 나타내었다. 결과적으로 개발된 melting curve 분석을 이용한 duplex real-time PCR 방법은 식품안전 증진을 위한 시간, 노동력, 비용 절감에 있어서 유효한 방법이 될 것으로 판단된다.

• 한국식품과학회지
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• 제37권6호
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• pp.1005-1011
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• 2005

본 연구에서는 높은 분리능을 가지고 있을 뿐만 아니라 실험의 재현성과 경제성의 측면에서도 많은 장점을 갖고 있는 ERIC DNA sequence를 응용한 ERIC-PCR을 이용하여 Salmonella, E. coli, Shigella, Vibrio 등 4속의 주요 그람 음성 식중독유발 세균들의 분리 동정 방법을 확립하고자 하였다. ERIC-PCR 결과, E. coli의 경우 0.3kb, 0.42kb 및 1.2kb의 band가 모든 균주에서 공통적으로 확인되었고, Salmonella속으로부터는 0.22kb, 0.4kb 및 0.7kb의 band가 증폭되었다. Shigella속은 모든 표준균주와 분리균주로부터 0.33kb와 1.25kb의 band가 증폭되었으며, S. sonnei의 경우 위의 주요 2개 band 이외에도 대부분의 균주에서 0.44kb, 2.0kb 및 3.05kb의 band가 증폭되어 다른 종의 Shigella와 구별되는 fingerprinting pattern을 나타내었다. 그리고 V. parahaemolyticus의 경우 표준균주와 분리균주 모두 0.51kb와 1.5kb의 band가 증폭되어 V. cholerae, V. mimicus 등과 같은 다른 종의 Vibrio와 구별되는 fingerprinting pattern을 나타내었다. 이와 같이 4속의 모든 식중독 균주마다 ERIC-PCR후 생성되는 fingerprinting pattern에서 3-5개의 공통적인 band가 증폭되는 것이 확인되어 이를 이용한 속 수준의 분리 동정과 이러한 주요 band들 이외의 부수적인 band들을 고려하여 종 수준까지의 분리도 가능함을 확인하였다. 따라서 본 연구의 결과는 ERIC 반복적 DNA 염기서열을 이용한 ERIC-PCR이 식중독균의 분리 동정 방법으로 사용될 수 있음을 확인하였으며, 나아가 더 많은 속(genus)의 식중독세균을 대상으로 한 새로운 분리 동정 방법을 확립하는데도 응용이 될 수 있을 것이다.