• 한국미생물·생명공학회지
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• 제42권2호
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• pp.99-105
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• 2014

가정에서 제조된 된장을 산성조건에서 계대 배양한 후 균체외 mannanase 를 생산하는 Bacillus sp. YB-1401를 분리하였다. 분리균의 당이용능을 비롯한 생화학적 특성은 Brevibacillus laterosporus와 유사도(61.1%)가 가장 높은 반면에 16S rRNA 유전자의 염기서열은 B. amyloliquefaciens와 유사도가 가장 높았다. 분리균 YB-1401의 mannanase 생산성은 mannans에 의해 급격하게 증가하였으며, 특히 곤약(4%)이 첨가된 배지에서 약 265 U/ml로 최대 생산성을 보였다. 분리균의 mannanase는 $55^{\circ}C$와 pH 5.5 반응조건에서 최대활성을 보였으며 pH 3.5-11.0의 범위에서 1시간 방치하였을 때 실활이 거의 일어나지 않았다. 또한 LBG와 guar gum 및 mannooligosaccharides를 mannanase로 분해하였을 때 주된 반응산물로 mannobiose와 mannotriose가 생성되었으며 mannose도 소량 생성되었다.

• Food Science and Biotechnology
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• 제17권3호
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• pp.447-456
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• 2008

Limonene, pinene, and isoprene are abundant and ubiquitous volatile organic compounds (VOCs) which are found in various natural products and also produced from various manufacture processes. Limonene and pinene are major components of food additives and household products for enrichment of good flavors and elimination of malodors, and isoprene is a basal motif of monoterpenes such as limonene and pinene. They have shown many beneficial effects such as chemopreventive, chemotherapeutic, and antioxidant activities. Upon certain conditions, however, adverse effects of these compounds on human health have also been reported. Although they do not seem to have acute and severe toxicity to human, they can easily generate secondary organic aerosols (SOAs) when they react with oxygen and/or ozone, which have shown certain toxic effects on experimental animal models as well as on humans. Numerous household and scented products containing limonene, pinene, and isoprene are widely used in these days. However, biological consequences upon exposure to these products are largely unknown. The aim of this review is to summarize and analyze the current understanding on the biological effects of VOCs, in particular limonene, pinene, and isoprene, as well as their SOAs.

• 한국식품위생안전성학회지
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• 제10권2호
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• pp.89-95
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• 1995

Highly lethal Listeria monocytogenes, causing bromatoxism through vegetables, dairy products, meat products and shellfish etc, was examined for possible contamination in market beef. USDA, FDA, Malthus and Modified Cold Enrichment methods were used for the detection of Listeria spp.. Samples of domestic and imported market beef were collected from local meat shopsat Seoul, Korea. Total two hundreds and six of Listeria spp. were isolated and identified from beef. Among 206 isolates, the number of L. welshimeri was one hundred and twenty-one(44.8%). The numbers of isolated L. innocua, L. murrayi, L. monocytogenes, L. grayi, L. seeligeri, and L. ivanovii were 49(18.1%), 14(5.2%), 12(4.4%), 6(2.2%), 2(0.7%), and 2(0.7%), respectively. Detection rates of Listeria spp. varied among four methods. The highest detection rate of Listeria spp. in market beef was found at USDA method and that of L. monocytogenes was found at Malthus method.

• Journal of Microbiology and Biotechnology
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• 제11권2호
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• pp.302-309
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• 2001

Colony blot hybridization using a VVHP DNA probe derived from the sequence of the hemolysin gene, vvhA, was specific in identifying all V. vulnificus strains, thereby, eliminating the need for any additional phenotypic identification. The colony blot hybridization procedure revealed a sensitivity and broad applicability sufficient for the direct enumeration of V. vulnificus in various natural samples, without the use of enrichment or culturing on selective medis. V. vulnificus was detected in all natural samples collected during August and May at concentrations ranging from $2.1{\times}10^1\;to\;4.0{\times}10^3$ organisms per ml. However, during November and February, when the mean temperatures of the seawater were $12^{\circ}C$ and $5^{\circ}C$, respectively, V. vulnificus was not detected in any natural samples.

• 한국식품위생안전성학회지
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• 제9권4호
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• pp.205-211
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• 1994

From 120 soil and activated sludge, the strains able to grow on benzoate and m-Toluate have been isolated after selective enrichment which were later identified as Psudomonas sp. according to its morphological and biochemical characteristics. Ben-2 strain contained two plasmid DNA having about 120 Kb and below 2.0 Kb by agarose gel electrophoresis. Form the comparative investigation of catechol 1,2-oxygenase and catechol 2,3-oxygenase activities in Ben-2 strain and its cured strain, Ben-2 strain has both of these two enzymes while cured strain has catechol 1,2-oxygenase only.

• 한국식품위생안전성학회지
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• 제31권6호
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• pp.465-470
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• 2016

본 연구는 전처리 방법이 새싹채소 재배에 사용되는 종자 중 식중독 세균의 검출율에 영향을 미치는지에 대해 검증하기 위해 시중 유통되고 있는 새싹채소 재배용 종자 19종을 수집하여 종자를 세척 방법과 발아 방법으로 전처리한 후 E. coli, E. coli O157:H7, Salmonella spp., L. monocytogenes의 검출율을 비교하였다. 또한 인위적으로 Salmonella enterica를 접종한 알팔파 종자에 대해서 무처리, 세척, 발아 방법으로 전처리한 후 S. enterica의 검출율을 검정하였다. 시중 유통되고 있는 종자를 수집하여 분석한 결과, 세척 방법과 발아 방법 등의 전처리 방법에 따라 E. coli 검출율과 양성시료에 차이가 있었음을 확인하였다. 인위적으로 S. enterica를 접종한 알팔파 종자에 대한 검출율 비교 검정에서도 분석시료량 대비 전처리방법별로 검출율이 차이가 나는 것으로 나타났고, 선택배지 종류에 따라서도 S. enterica의 검출율이 차이가 났다. 결론적으로 새싹채소 재배용 종자의 식중독 세균 분석에 있어서 종자의 전처리 방법, 시료당 분석시료량, 선택배지 종류 등이 검출율에 영향을 미치는 것으로 나타났다.

• Journal of Microbiology and Biotechnology
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• 제18권10호
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• pp.1689-1694
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• 2008

The ability to detect Salmonella spp. is essential in the prevention of foodborne illness. This study examined a Salmonella spp. detection method involving the application of immunomagnetic separation and immunoliposomes (IMS/IL) encapsulating sulforhodamine B (SRB), a fluorescent dye. A quantitative assay was conducted by measuring the fluorescence intensity of SRB that was produced from an immunomagnetic bead-Salmonella spp.-immunoliposome complex. The results indicated detection limits of $2.7{\times}10^{5}$ and $5.2{\times}10^{3}$ CFU/ml for Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) and Salmonella enterka subsp. enterka serovar Typhimurium (S. Typhimurium), respectivley. The signal/noise ratio was improved by using 4% skim milk as a wash solution rather than 2% BSA. In addition, higher fluorescence intensity was obtained by increasing the liposome size. Compared with the conventional plating method, which takes 3-4 days for the isolation and identification of Salmonella spp., the total assay time of to h only including 6 h of culture enrichment was necessary for the Salmonella detection by IMS/IL. These results indicate that the IMS/ IL has great potential as an alternative rapid method for Salmonella detection.

• Journal of Microbiology and Biotechnology
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• 제16권8호
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• pp.1301-1305
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• 2006

The development of rapid, infallible, and sensitive methods of detecting foodborne pathogens has received much impetus in recent years owing to an increased public awareness of the health hazards. For the rapid and simultaneous detection of these foodborne pathogens, a multiplex PCR method was developed. Yersinia enterocolitica, Staphylococcus aureus, and Shigella spp. are bacteria of concern because of their specific growing condition that enables them to live at low temperatures. In order to detect each pathogenic bacterium, specific primers from Y. enterocolitica, St. aureus, and Sh. flexneri were selected and validated successfully. To apply this method to food stored at low temperature, Y. enterocolitica, St. aureus, and Sh. flexneri were artificially inoculated in lettuce and incubated for enrichment. The multiplex PCR assays were able to simultaneously detect three pathogens, and the presence of three bands was observed at initial inoculation levels of approximately 1$\times$10$^1$ CFU/g in lettuce. Therefore, this method could be used for simultaneous detection of Y. enterocolitica, St. aureus, and Shigella spp. contaminated in lettuce during cultivation, transportation, preservation, and storage.

• 한국식품영양학회지
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• 제27권2호
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• pp.256-266
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• 2014

The purpose of this study was to determine the optimal mixing conditions of soybean oil and bread crumbs mixture for pork patty. The experiment was designed according to the central composite design of response surface methodology. There were ten experimental points, including two replicates for soybean oil and bread crumbs. The physicochemical and mechanical analyses of each sample, including pH, cooking loss, thickness increase, moisture content, lightness, hardness, adhesiveness, springiness, chewiness, and gumminess showed significant differences (p<0.05). The results of sensory evaluation showed significant differences in tenderness, juiciness, and overall quality (p<0.05). The optimum formulation calculated by numerical and graphical method was 13.61 g of soybean oil and 6.35 g of bread crumbs. The results obtained in this study will be useful to the meat industry, which tends to decrease the saturated fatty acid content with a concomitant enrichment in the unsaturated fatty acids content.

• Preventive Nutrition and Food Science
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• 제20권4호
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• pp.284-291
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• 2015

In this study, we attempted to enrich cyclo-His-Pro (CHP) using enzymatic hydrolysis of yeast and to evaluate the functionality of yeast hydrolysate (YH)-enriched CHP. Flavourzyme offered a better performance in enhancing CHP content than other proteases. The CHP enrichment conditions were optimized as follows: addition of 1% Flavourzyme, 48-h incubation at 60oC, and pH 6.0. The CHP content significantly increased by 20-fold after ultra-filtration (UF). Maximal CHP translation was obtained after heating for 8 h at 50oC and pH 7.0. YH showed poor foaming capacity between pH 3.0 to 9.0. The emulsifying activities of YHs were slightly higher at near acidic pH. Increase in heating temperature and time resulted in decreased CHP content. The results indicate that YH is more heat stable after UF. Therefore, the CHP in YH after UF can be used as a food additive with physiological CHP activity and high heat stability.