• 한국식품과학회지
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• 제21권3호
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• pp.435-440
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• 1989

식품의 안전성 평가를 위한 기초자료로서 각종 활성산소 소거제 및 환원제를 사용하여 식품성분간의 상호반응에 의하여 당의 분해로 생성되는 저분자 카르보닐 화합물의 돌연변이원성과 그 억제기구를 검토하였다. 그 결과, 카르보닐화합물의 돌연변이원성은 glyceraldehyde 등의 ${\alpha}-hydroxycarbonyl$ 화합물보다 glyoxal등의 ${\alpha}-dicarbonyl$ 화합물이 큰 것으로 나타났으며, 그 중에서 methyl glyoxal이 가장 큰 것으로 밝혀졌다. 각종 활성산소 소거제 및 환원제의 돌연변이원성 억제작용은 cysteine, glutathione 및 sodium bisulfite의 억제작용이 큰 것으로 나타나 이들 카르보닐화합물의 돌연변이원성은 주로 산화에 의해 생성되는 일중항산소$(^1O_2)$ 및 그 자체의 반응성에 크게 기인하는 것으로 밝혀졌다. 또한, 이들 카르보닐화합물의 돌연변이원성은 첨가된 활성산소 소거제에 의하여 카르보닐화합물의 자동산화로 생성된 일중항산소, 수산라디칼, 과산화수소 및 superoxide anion 등의 소거 및 환원제에 의하여 카르보닐화합물의 반응성의 소실로 인하여 억제되는 것으로 생각된다. 한편, 공시한 각 활성산소 소거제 및 환원제 단독으로는 돌연변이원성이 없는 것으로 나타났다.

• 한국식품조리과학회지
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• 제14권4호
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• pp.333-338
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• 1998

산마의 총 식이섬유가 2-AF와 MNNG에 대해서는 각각12.4%와 18.7%의 억제효과를 나타냈으며, 재배마는 33.2%와 49.1%의 억제효과를 보여 재배마의 $\alpha$-cellulose는 각각 0.5%, 1.0%농도에서 70.0%와 76.9%로 가장 높은 억제효과를 나타냈으며 MNNG에 대해서는 모든 농도에서 90% 이상의 억제효과를 나타냈다. Pectin의 2-AF에 대한 억제효과는 산마의 경우 0.1% 농도일 때 42.5%로 가장 높았고, 재배마는 억제효과를 나타내지 않았다. MNNG에 대해서는 산마 1.0%와 재배마 0.7% 농도일 때 각각 51.8% 와 31.0%로 가장 높은 억제효과를 나타냈다. 반응 시간에 따른 억제 효과는 2-AF에 대해 산마, 재배마 및 표품의 $\alpha$-cellulose (0.5%)는 3시간일 때, MNNG에 대해서는 6시간일 때 최고의 억제 효과를 나타냈다. 산마, 재배마 및 표품의 pectin(1.0%)의 2-AF에 대해 반응 시간이 경과함에 따라 억제 효과가 점진적으로 감소하였으며 MNNG에 대해 1시간 30분일 때 높은 억제 효과를 나타냈다. 산마와 재배마에서 추출한 $\alpha$-cellulose와 pectin은 2-AF에 의해 유발되는 돌연변이원성에 비해 MNNG에 의해 유발되는 돌연변이원성을 더 효과적으로 억제하였다.

• 한국식품조리과학회지
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• 제26권2호
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• pp.165-170
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• 2010

Although the demand of ready-to-eat (RTE) foods such as Kimbab is growing, large quantities and wide distribution of these foods is difficult due to their short shelf-life, exposed packaging with hygienic risk, and decreased quality at refrigerator temperatures. This study was undertaken to develop preservation and storage methods to extend the shelf-life of RTE rice products using microwave and packaging methods such as vacuum and modified atmosphere packages. RTE rice ball samples inoculated with Escherichia coli, Salmonella Typhimurium, Listeria monocytogenes, Staphylococcus aureus or Bacillus cereus were microwave treated for 0, 30, 60, 90 and 120 seconds. Populations of pathogens on the rice balls were significantly reduced with an increase in treatment time. There were more than 5 log reductions of all pathogens when the samples were microwave treated for 60 seconds. RTE rice balls inoculated with two pathogens (S. aureus and B. cereus) were packaged via air, vacuum, $N_2$ gas, and $CO_2$ gas following microwave treatment for 90 seconds. The initial S. aureus and B. cereus concentration before treatment was 7.60 and 6.59 log CFU/g, and these levels were reduced by 3.37 and 2.18 log CFU/g after microwave treatment. The levels of pathogens were significantly increased during storage time at room temperature. $CO_2$ packaging was the most effective at inhibiting microbial growth among the tested packaging methods. The levels of total mesophilic count, S. aureus and B. cereus after 5 days of storage were 7.7, 8.8 and 9.3 log CFU/g in air packaged samples and 2.4, 3.2 and 8.3 log CFU/g in $CO_2$ gas packaged samples, respectively. However, after 3 days of storage higher levels of B. cereus were observed in all samples, indicating that the samples were not safe to be consumed. Base on these results, microwave treatment and MAP packaging methods using $CO_2$ gas could be used as a potential method for extending the shelf-life of RTE foods.

• 한국축산식품학회지
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• 제29권2호
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• pp.269-277
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• 2009

이 연구는 기능성 요구르트를 이용한 신선계육의 포장이 냉장유통조건에서 닭고기의 미생물학적, 이화학적, 그리고 관능적 품질특성에 미치는 영향을 알아보기 위하여 실시되었다. 닭고기의 가슴살, 정육, 절단육을 기능성 요구르트와 함께 폴리에칠렌 백에 포장한 다음, $10^{\circ}C$에서 저장하면서 0, 2, 4, 7일 후에 시료를 채취하여 미생물학적, 이화학적 품질 특성을 요구르트를 첨가하지 않은 대조구와 비교하였다. 기능성 요구르트를 첨가한 포장에서 저장기간을 통하여 총미생물수와 대장균군의 수가 현저하게 감소하였으며, 대조구의 경우에는 $10^{\circ}C$에서 2일 저장 후에 미생물학적 또는 관능적인 품질 기준의 한계에 도달하였으나, 기능성 요구르트를 첨가한 포장에서는 동일한 조건에서 4일 후에도 신선육의 품질기준에 적합한 상태로 유지되었다. 따라서 이 연구에서 확인된 결과에 의하면 기능성 요구르트를 이용한 신선계육의 포장방법은 냉장유통 되는 닭고기의 총세균수와 대장균수를 현저히 낮추어줌으로써 유통기한을 연장할 수 있는 새로운 방법으로 이용할 수 있을 것으로 사료된다.

• Toxicological Research
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• 제20권4호
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• pp.365-374
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• 2004

Inhalation toxicity, mutagenicity, and immunotoxicity tests were performed using a smoke generation system to investigate the safety of Herbrette, a tobacco substitute made with the leaves of Perilla frutescens. ICR mice were exposed to nicotine-free Herbrette smoke with concentrations of 0 (control), 4.08 $\pm$ 1.32 mg/$m^3$ (low dose), 7.72 $\pm$ 2.14 mg/$m^3$ (medium dose) and 12.83 $\pm$ 1.69 mg/$m^3$ (high dose) total particulate matters (TPM) for 4 weeks. When compared to the control group, the body weights, organ weights in the exposed groups did not show any significant differences. However, certain change of several serum chemical data and biochemical parameters were observed, however, the changes were within normal physiological ranges. Moreover, no changes in organ weight, and no gross/microscopic changes were observed between the exposed and control groups. Salmonella typhimurium reverse mutation, in vivo chromosomal aberration and micronucleus assays revealed that Herbrette did not induce mutagenicity. Upon evaluation of peripheral cellular immunity of mice through in vitro lymphocyte proliferation assay, no significant difference was observed in mean stimulation index between the exposed and control groups. Taken together, our results strongly suggest that Herbrette may not cause toxicity on mice under current condition.

• Molecular & Cellular Toxicology
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• 제2권3호
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• pp.176-184
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• 2006

The controversy on genotoxicity of molinate, an herbicide, has been reported in bacterial system, and in vitro and in vivo mammalian systems. To clarify the genotoxicity of molinate, we performed bacterial gene mutation test, in vitro chromosome aberration and mouse lymphoma $tk^{+/-}$ gene assay, and in vivo micronucleus assay using bone marrow cells and peripheral reticulocytes of mice. In bacterial gene mutation assay, no mutagenicity of molinate ($12-185{\mu}g/plate$) was observed in Salmonella typhimurium TA 98, 100, 1535 and 1537 both in the absence and in the presence of S-9 metabolic activation system. The clastogenicity of molinate was observed in the presence ($102.1-408.2\;{\mu}g/mL$) of metabolic activation system in mammalian cell system using Chinese hamster lung fibroblast. However, no clastogenicity was observed in the absence ($13.6-54.3\;{\mu}g/mL$) of metabolic activation system. It is suggested that the genotoxicity of molinate was derived some metabolites by metabolic activation. Molinate was also subjected to mouse lymphoma L5178Y $tk^{+/-}$ cells using microtiter cloning technique. In the absence of S-9 mixture, mutation frequencies (MFs) were revealed $1.4-1.9{\times}10^{-4}$ with no statistical significance. However, MFs in the presence of metabolic activation system revealed $3.2-3.4{\times}10^{-4}$ with statistical significance (p<0.05). In vivo micronucleus (MN) assay using mouse bone marrow cells, molinate revealed genotoxic potential in the dose ranges of 100-398 mg/kg of molinate when administered orally. Molinate also subjected to acridine orange MN assay with mouse peripheral reticulocytes. The frequency of micronucleated reticulocytes (MNRETs) induced 48 hr after i.p. injection at a single dose of 91, 182 and 363 mg/kg of molinate was dose-dependently increased as $10.2{\pm}4.7,\;14.6{\pm}3.9\;and\;28.6{\pm}6.3\;(mean{\pm}SD\;of\;MNRETs/2,000\;reticulocytes)$ with statistical significance (p<0.05), respectively. Consequently, genotoxic potential of molinate was observed in in vitro mammalian mutagenicity systems only in the presence of metabolic activation system and in vivo MN assay using both bone marrow cells and peripheral reticulocytes in the dose ranges used in this experiment. These results suggest that metabolic activation plays a critical role to express the genotoxicity of molinate in in vitro and in vivo mammalian system.

• 한국식품저장유통학회지
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• 제20권5호
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• pp.712-719
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• 2013

본 연구에서는 수입되는 발효유 starter를 대체하기 위해 전통발효식품으로부터 유산균을 분리 및 동정하여 이를 이용한 유산균주의 발효유 적합성 및 probiotics로서의 가능성을 확인하기 위한 기초자료로 사용하고자 실시하였다. 전통발효식품 배추김치, 젓갈 및 장류에서 분리해 낸 유산균주는 11종이며, 이 중 내산성 및 내담즙성이 우수한 L. plantarum A, Leu. lactis B 및 L. acidophilus C를 선택하여 항균활성 및 발효유제조 적용연구를 실시하였다. 3종의 균종에 대한 항균활성은 병원성 미생물인 Li. monocytogenes NCTC 11994에 대해서 높은 항균활성을 보였다. 항균활성이 있는 3종의 유산균주를 사용하여 발효유를 제조한 결과 대조구인 ABT 5보다는 미생물학적 및 이화학적 변화가 유의적으로 차이는 났으나 관능검사 결과 색, 향기, 조직감, 맛 및 전체적인 기호도가 대조구 대비 80% 이상으로 단독 균주임을 감안하면 우수한 관능적 특성을 가지고 있고, 추후 관능적 특성을 높이기 위한 복합균주에 대한 연구가 추가적으로 진행된다면 발효유 스타터로서의 이용 가능성이 높을 것으로 판단된다.

• 한국수산과학회지
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• 제33권5호
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• pp.388-392
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• 2000

Alginate의 광범위하고 효율적인 이용을 목적으로 평균분자량이 약 10,000 (HAG-10), 50,000 (HAG-50) 및 100,000 (HAG-100) 정도의 저분자 alginate를 제조하였으며, 이 저분자 alginate의 항돌연변이 효과와 cholesterol, glucose 및 카드뮴과의 결합능을 측정하여 그 물리${\cdot}$화학적 특성을 비교, 검토하였다. Ames test로 저분자 alginate의 항돌연변이 효과를 측정한 결과, $aflatoxin B_1 (AFB_1)$에 대한 간접돌연변이원성과 N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)에 대한 직접돌연변이원성의 항돌연변이 효과는 HAG-10이 가장 높았고, 다음으로 HAG-50, HAG-100 및 alginate의 순으로 나타나 저분자화가 진행될수록 그 효과는 증가하는 것으로 나타났다. 저분자 alginate의 cholesterol, glucose 및 카드뮴에 대한 결합능은 alginate가 가장 높았고, 다음으로 HAG-50과 HAG-100은 유사하였으며, HAG-10은 결합능을 거의 보이지 않았다.

• 한국약용작물학회지
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• 제18권6호
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• pp.389-397
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• 2010

This work was to improve antimicrobial activities of horseradish by encapsulated with edible biopolymers such as lecithin and gelatin since it has been difficult to directly use horseradish extracts into foods and food containers due to its strong and undesirable flavors. It was shown that most of the nanoparticles containing the extracts were well formed in round shape with below 400 nm diameter as well as fairly stable and less odd flavors in various pH ranges by measuring zeta potentials. The encapsulation efficiencies of nanoparticles were estimated as 66.6% and 53.4% for lecithin and gelatin, respectively. Minimal Inhibitory Concentration (MIC) of both nanoparticles against G(+), Listeria monocytogenes and G(-), Salmonella typhimurium were also measured as 79 ppm based on AIT concentrations in the extracts, whose activities were about 65% higher than the case of adding crude extract. It was also found that the nanoparticles efficiently penetrated into the cell membrane and started to destruct the cells after 6 hours cultivation under Transmision Electron Microscopy observation. These results prove that the nano-encapsulation of the horseradish extracts can be employed to directly treat into the foods and food containers for antimicrobial purposes with the aids of aerosolization system, by using small amounts of the extracts and having less flavors due to masking effects of nanoparticles.

• Journal of Microbiology and Biotechnology
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• 제20권12호
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• pp.1735-1743
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• 2010

The full-length genes gyrB (2,415 bp), parC (2,277 bp), and parE (1,896 bp) in Edwardsiella tarda were cloned by PCR with degenerate primers based on the sequence of the respective quinolone resistance-determining region (QRDR), followed by elongation of 5' and 3' ends using cassette ligation-mediated PCR (CLMP). Analysis of the cloned genes revealed open reading frames (ORFs) encoding proteins of 804 (GyrB), 758 (ParC), and 631 (ParE) amino acids with conserved gyrase/topoisomerase features and motifs important for enzymatic function. The ORFs were preceded by putative promoters, ribosome binding sites, and inverted repeats with the potential to form cruciform structures for binding of DNA-binding proteins. When comparing the deduced amino acid sequences of E. tarda GyrB, ParC, and ParE with those of the corresponding proteins in other bacteria, they were found to be most closely related to Escherichia coli GyrB (87.6% identity), Klebsiella pneumoniae ParC (78.8% identity), and Salmonella Typhimurium ParE (89.5% identity), respectively. The two topoisomerase genes, parC and parE, were found to be contiguous on the E. tarda chromosome. All 18 quinolone-resistant isolates obtained from Korea thus far did not contain subunit alternations apart from a substitution in GyrA (Ser83$\rightarrow$Arg). However, an alteration in the QRDR of ParC (Ser84$\rightarrow$Ile) following an amino acid substitution in GyrA (Asp87$\rightarrow$Gly) was detected in E. tarda mutants selected in vitro at $8{\mu}g/ml$ ciprofloxacin (CIP). A mutant with a GyrB (Ser464$\rightarrow$Leu) and GyrA (Asp87$\rightarrow$Gly) substitution did not show a significant increase in the minimum inhibitory concentration (MIC) of CIP. None of the in vitro mutants exhibited mutations in parE. Thus, gyrA and parC should be considered to be the primary and secondary targets, respectively, of quinolones in E. tarda.