• 한국식품저장유통학회지
• /
• 제16권5호
• /
• pp.759-764
• /
• 2009

매실에 설탕을 가한 후 삼투압의 원리를 이용하여 제조한 매실 침출액의 총고형분은 55.08%였고, pH는 3.1이었으며, 산도는 구연산으로서 1.52%였다. 이 매실 침출액의 식중독세균에 대한 항균활성을 조사한 결과, 공시된 모든 균주 중에서Vibrio parahaemolyticus에 대해 31.2 mm의 저해환을 보여 이 균에 대한 매실 침출액의 항균활성이 가장 강하였고, 다음으로 Bacillus cereus, Staphylococcus aureus 및 Salmonella typhymurium의 순으로 활성이 강하였다. 매실 침출액은 공시된 모든 시험균주에 대해 생육저해효과가 있는 것으로 나타났다. 특히 Vibrio parahaemolyticus에 대해서는 0.25%에서 생육이 억제되어 생육저해효과가 가장 높은 것으로 나타났고, 이 균에 대한 MIC도 1.0%로 가장 낮았다. Bacillus cereus와 Staphylococcus aureus에 대해서는 2%이상의 농도에서는 생육이 완전히 억제되었으나, 1.0%이하의 농도에서는 생육이 촉진되는 것으로 나타나 매실 침출액 중의 미지의 성분이 이들의 주요 영양원으로 이용되었음을 알 수 있었다. 매실 침출액의 열 및 pH 안정성을 측정한 결과, $65{\sim}125^{\circ}C$의 온도범위에서 열에 안정하였고, pH 7로의 중화에 따른 영향을 받지 않았다.

• 한국임상수의학회지
• /
• 제24권2호
• /
• pp.130-136
• /
• 2007

Artemisia capillaris THUNB is a perennial herb that belongs to the family Compositae spp and the most common plant among the various herbal folk remedies used in treatment of abdominal pain, hepatitis, chronic liver disease, jaundice and coughing in Korea. In this study, antimicrobial effects of Artemisia capillaris extracts on the food poisoning bacteria were investigated for further clinical application, which is an alternative for the use of antibiotics and their unexpected resistance. Artemisia capillaris extract using ethyl acetate showed the highest antimicrobial effects on S. enteritidis, E. coli O157 : H7, L. monocytogenes and S. aureus. The chloroform extract showed strong effects on all kinds of bacteria; whereas ethanol and methanol extracts showed weaker effects. Finally, ether and water extracts showed the weakest effects under the same conditions. The minimum inhibitory concentration (MIC) of ethyl acetate extract was 1 mg/mL for E. coli O157 : H7 and L. monocytogenes, and 2 mg/mL for S. enteritidis and S. aureus. The inhibitory effects on all the bacteria continued for 12 hours after incubation using 20 mg/mL and 30 mg/mL of ethyl acetate extract. The inhibitory effects continued maximally for 72 hours. The results of these studies indicate Artemisia capillaris extract exhibited excellent antimicrobial and inhibitory effects on the food poisoning pathogenic bacteria; S. enteritidis, E. coli O157 : H7, L. monocytogenes and S. aureus.

• Journal of Advanced Marine Engineering and Technology
• /
• 제37권8호
• /
• pp.855-861
• /
• 2013

저온에서 NOx 저감률이 높은 작은 기공을 갖는 Cu-chabazite SCR 촉매는 150 에서 $300^{\circ}C$ 범위의 낮은 배기가스 온도를 갖는 박용 디젤엔진에 적용성이 높다. 불행하게도, 박용디젤엔진용 연료는 체적베이스로 1.5% 이상의 높은 레벨의 황을 함유 할 수 있다. 이것은 공연비 50:1로 엔진 운전시에 배기가스에 이산화황의 레벨이 500 ppm에 해당된다. 배기가스에 포함되어 있는 높은 레벨의 이산화황은 Cu-chabazite SCR 촉매의 NOx 저감률을 감소시키는 역할을 할 수 있다. 본 연구에서는 Cu-chabazite SCR촉매의 황 피독에 의한 NOx 저감 성능을 연구하기 위하여 벤치플로 시스템을 구축하였다. Cu-chabazite SCR 촉매를 황 피독 시키기 위하여 5% 이산화탄소, 14% 산소, 5% 물과 나머지 질소로 만들어진 배기가스에 500 ppm의 이산화황을 각각 150, 200, 250, $300^{\circ}C$에서 2시간씩 노출 시켰다. 황 피독후 Cu-chabazite SCR 촉매의 불활성 한계를 측정하기 위하여 저온(150~$300^{\circ}C$)에서 NOx 저감 성능을 평가하였다. 또한, 600 과 $700^{\circ}C$에서 각각 30분씩 탈황 작업을 수행하여, 황 피독된 Cu-chabazite SCR 촉매의 NOx 저감 성능이 회복될 수 있는 온도를 결정하였다.

• 한국식품위생안전성학회지
• /
• 제16권1호
• /
• pp.11-15
• /
• 2001

한천은 국내의 풍부한 수산자원 중의 하나이나, 그 자체로만 이용할 뿐 가공을 통한 이용률은 떨어지고 있다. 따라서 한천의 이용 효율을 높이기 위하여 장내 균총 중의 유해균과 유익균에 대한 한천 올리고당의 증식저해 및 증진효과를 알아보았다. 장내 균총 중 유해균으로 Clostridium perfringens를 유익균으로 Bifidobacterium infantis를 대표군으로 하여 한천 올리고당의 효과를 살펴본 결과, 한천 올리고당을 0.2% 첨가한 경우 B. infantis은 증식이 현저하게 상승한 반면 Cl. perfringens는 효과가 없었다. 또한 pH 및 NaCl의 농도에 따라 한천 올리고당이 장내 균총에 미치는 영향에 차이가 있어, B. infantis은 pH 4.5 이상과 염 농도 1%이내에서 증진된 반면 Cl. perfringens은 염농도에서만 차이가 있었다. 이들을 혼합하여 배양한 결과 B. infantis의 증식이 증가함에 따라 Cl. perfringens의 증식은 현저히 억제되는 현상이 관찰되었다.

• 한국식품위생안전성학회지
• /
• 제16권3호
• /
• pp.159-167
• /
• 2001

집단식중독 환자에서 분리한 Staphylococcus aureus에 대한 항생제 감수성, enterotoxin 형별을 PCR로 조사한 결과는 다음과 같았다. 1. 의심환자분변 413건중 105건(25.4%)에서 Staphylococcus aureus coagulase 양성 균주가 분리되었다. 2. enterotoxin 생산성을 PCR로 조사한 결과 총 45주(42.9%)에서 enterotoxin gene이 확인되었으며, 이 중 H형 단독생산주가 29주(64.4%)로 가장 많았으며. A형 단독생산주 5주(11.1%), A형 및 H형 혼합생산주 4주(8.9%), G형 생산주 2주(4.4%)및 I형 생산주 1주(2.2%)이었다. 3. 시험한 105주 중 48주(45.7%)에서 항생제 내성이 확인되었으며, 이 중 penicillin에 대한 내성이 38.1%로 가장 높았으며, ampicillin과 penicillin은 중등도 내성이 각각 42.9%, 61.0%이었다. chloramphenicol, clindamycin, methicillin. trimethoprim, vancomycin은 모두 감수성이었다. 또한 단제 내성이 85.4%를 차지하였으며, 2제 내성이 12.5%, 3제내성이 2.1%이었다.

• 한국수산과학회지
• /
• 제53권6호
• /
• pp.851-860
• /
• 2020

Shrimp in seasoned soy sauce (S-SS) is a popular seafood product in Korea, but it could be potentially hazardous; thus, this study was conducted to investigate its safety. Commercial S-SS were collected and analyzed for pH, volatile basic nitrogen (VBN), hygenic indicator microorganisms (viable cell count, coliforms, and Escherichia coli), food poisoning bacteria (Staphylococcus aureus, Vibrio parahaemolyticus, and Listeria monocytogenes), preservatives (dehydroacetic acid, sorbic acid, benzoic acid, and its salt, parahydroxybenzoate), tar colorants, and sensory properties. Domestic and foreign standards were also investigated for S-SS. Commercial S-SS ranged from to 6.2-7.3 for pH, 13.7-39.1 mg/100 g for VBN, and 4.6-6.9 log CFU/g for viable cells. The coliforms and E. coli of commercial S-SS were from ND to 3.4 log CFU/g and negative, respectively. Food poisoning bacteria, preservatives, and tar colorants were not detected in commercial S-SS. Only the coliform count and presence of E. coli in commercial S-SS exceeded the set standards of vietnam, while all items were within domestic and foreign standards.

• Journal of Electrochemical Science and Technology
• /
• 제9권2호
• /
• pp.133-140
• /
• 2018

$Sr_{0.92}Y_{0.08}Ti_{0.5}Fe_{0.5}O_{3-{\delta}}$ (SYTF0.5) is investigated as an alternative anode in $H_2$ fuels containing $H_2S$ (0-200 ppm). Although additional ionic conductivity is introduced by aliovalent substitution of $Ti^{4+}$ by $Fe^{3+}$ in the B-site, the SYTF0.5 has lower electrical conductivity than that of the $Sr_{0.92}Y_{0.08}TiO_{3-{\delta}}$. Due to the mixed ionic and electronic conductive (MIEC) property exhibited in the SYTF0.5 anode, the electrochemical performance of the SYTF0.5 anode is improved, as well as the sulfur tolerance. The maximum power densities in $H_2$ at $900^{\circ}C$ for the SYT anode and the SYTF0.5 anode were 56.9 and $98.6mW/cm^2$, respectively. The maximum power density in the SYTF0.5 anode at 200 ppm of $H_2S$ concentration decreased by only 12.9% (86.3 to $75.2mW/cm^2$).

• Journal of Industrial and Engineering Chemistry
• /
• 제68권
• /
• pp.187-195
• /
• 2018

$Sr_{0.92}Y_{0.08}Ti_{1-x}Ni_xO_{3-{\delta}}$ (SYTN) was investigated in the presence of $H_2S$ containing fuels to assess the feasibility of employing oxide materials as alternative anodes. Aliovalent substitution of $Ni^{2+}$ into $Ti^{4+}$ increased the ionic conductivity of perovskite, leading to improved electrochemical performance of the SYTN anode. The maximum power densities were 32.4 and $45.3mW/cm^2$ in $H_2$ at $900^{\circ}C$ for the SYT anode and the SYTN anode, respectively. However, the maximum power densities in 300 ppm of $H_2S$ decreased by 7% and by 46% in the SYT and the SYTN anodes, respectively. To enhance the sulfur tolerance and to improve the electrochemical properties, the surface of SYTN anode was modified with samarium doped ceria (SDC) using the sol-gel coating method. For the SDC-modified SYTN anode, the cell performance was mostly recovered in the pure $H_2$ condition after 500-ppm $H_2S$ exposure in contrast to the irreversible cell performance degradation exhibited in the unmodified SYTN anode.

• 한국패류학회지
• /
• 제2권1호
• /
• pp.1-9
• /
• 1986

The authors carried out paralytic shellfish poison bioassay on the 9 kinds of shellfishes collected from Pusan and Kyungnam areas of Korea from April to July, 1986. The areas are the main producing district of fisheries in Korea and the samples were collected from their producing sites-natural, cultured and marketed. There were little or no PSP in the majority of the shellfishes, but 3 natural (Pusan Il-Kwang $700{\mu}g$, Koje Okpo $648{\mu}g$, Chungmoo Madong $124{\mu}g/100gm$ meat) and 1 marketed (Pusan Chakalchi $490{\mu}g/100gm$ meat) blue mussels contained relatively high PSP only in April. It is considered that there will be a possibility of paralytic shellfish poisoning, and control program for preventing the poisoning is necessary in Korea.

• 한국광물학회지
• /
• 제12권1호
• /
• pp.43-53
• /
• 1999

The medical mineral menas a single mineral or a complex of minerals. It is natural material. using the medical action of he major or the minor elements, and traditional medicine stuff which has been used since long time ago. Jusa, cinnabar as the mineral name, is the product of the hydrothermal process. It is used to relax the body and cure high blood pressure, apoplexy and cardiopathy. Jusais the major component of "An shin hwan" and "Woo hwang chung shim hwan" nowadays because it has such an excellent calm effect. In addition, it is used to cure cancers such as esophageal cancer and gastric cancer. Jusa composed of mercuric sulfide causes mercury poisoning such as Minamata disease. It is dealt with mineralogical property and chemical composition medical stuff in Korea and China, as well asmercury poisoning and medical action of Jusa in this study. In order to predct accumulation of the interior of the body of the major and minor elements in Jusa, leaching experiment of Jusa by artificial gastric juice was done as well as thermodynamic reaction modelling to know concentration of each species of body fluid. The minor elements of 24 species such as As, Pb, Cd, a and Fe by leaching reaction of Jusa and artificial gastric juice were leached. We can know the fact that as is less than 1 ppm, Hg is less than 25 ppm and Cd and m are not detected. In addition, mercury exists as species of Hg2+, HgCl+, HgCl2, HgCl3-, HgCl42-, HgClOH, HgS(H2S)2, Hg(HS)3-, HgS22-, HgOH and Hg(OH)2 by reaction modelling between Jusa and artificial gastric juice. The concentration of sulfide complexes is 24.2 ppm and that of others is less than 10 ppm. According to increasing pH, the concentration of HgS(H2S)2, Hg(HS)3+, HgS22- and Hg(OH)2 increases, whereas the concentration of HgCl+, HgCl2, HgCl3- and HgCl42- decreases. Therefore, Jusa is very useful for the development of new medicine because it is possible to predict formation of the body species and species accumulation on mercury known as a toxic element and concentration changes of toxicity and efficiency.city and efficiency.