• 한국미생물·생명공학회지
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• 제40권4호
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• pp.303-309
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• 2012

Keratinases are of particular interest because of their action on insoluble keratins and generally on a broad range of protein substrates. Alkalophilic and neutrophilic actinomycete strains isolated from different soil samples, rich in keratinaceous substances were screened for keratinolytic activity. An alkalophilic isolate, TBG-S13A5, was found to possess good keratinolytic activity and was able to utilize feather as the sole carbon and nitrogen source. TBG-S13A5 exhibited an off-white aerial mass color with a rectus-flexibilis type of spore chain. The morphological, microscopical and biochemical characters were comparable with that of Streptomyces albidoflavus. Fatty acid methyl ester profiling (FAME) and 16S rDNA sequence analysis confirmed its identity as a strain of S. albidoflavus. Under submerged fermentation conditions, maximum protease production was recorded on the $5^{th}$ day of incubation at $30^{\circ}C$, using basal broth of pH 9.0 with 0.25% (w/v) white chicken feather. This strain could affect feather degradation when the initial pH was 8 and above and maximum protease production was recorded when the initial pH was around 10.5. The effectiveness of the crude enzyme in destaining and leather dehairing were also demonstrated.

• 대한수의학회지
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• 제37권1호
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• pp.137-146
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• 1997

About Clostridium perfringens causing clinically necrotic enteritis or isolated from the intestinal contens of healthy chicken, We examined the usefulness of a rapid identification method by gas-liquid chromatography as well as the types of toxins. For this study, there were used 169 chickens including 116 broilers, 27 layers and 26 breeders which collected from 9 healty flock and 21 diseased flock showing necrotic enteritis. Among them, Cl perfringens was isolated from 30 chickens(17.8%) including 7 breeders(26.9%), 5 layers(18.5%) and 18 broilers(15.5%). Isolation of Cl perfringens was mainly from ceca (100%) and followed by small intestines(70.0%) and livers(16.7%), respectively. Average concentration of the pathogen in intestinal contents was $10^{3.8}CFU/g$ in cases occuring necrotic enteritis and on the contrary $10^{3.8}CFU/g$ in healthy cases. All isolates tested showed the same characterstics in biochemical tests compared to those in standard strain. Analysis of gas-liquid chromatography to volatile fatty acids produced by Cl perfringens in PYG broth showed the typical peaks of acetic and butyric acids compatible with the standard chromogram and was confirmed as a effective and reliable tool for rapid identification of the bacteria. Toxin types of 30 strains were mostly classified in A type(26 isolates) and the rest in C type(2 isolates) and unidentifed type(2 isolates). All the isolates were highly susceptible to amphicillin, amoxicillin and cephalothin.

• 한국축산식품학회지
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• 제40권5호
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• pp.758-771
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• 2020

This study was to investigate the prevalence and characteristics of antimicrobial-resistant Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) from 4,264 retail meat samples including beef, pork, and chicken in Korea between 2013 and 2018. A broth microdilution antimicrobial susceptibility testing was performed for S. aureus. Molecular typing by multilocus sequence typing (MLST), spa typing, and pulsed-field gel electrophoresis (PFGE), was performed on mecA-positive S. aureus strain. S. aureus was isolated at a rate of 18.2% (777/4,264), of which MRSA comprised 0.7% (29 strains). MLST analysis showed that 11 out of the 29 MRSA isolates were predominantly sequence type (ST) 398 (37.9%). In addition, ST72, ST692, ST188, ST9, and ST630 were identified in the MRSA isolates. The spa typing results were classified into 11 types and showed a high correlation with MLST. The antimicrobial resistance assays revealed that MRSA showed 100% resistance to cefoxitin and penicillin. In addition, resistance to tetracycline (62.1%), clindamycin (55.2%), and erythromycin (55.2%) was relatively high; 27 of the 29 MRSA isolates exhibited multidrug resistance. PFGE analysis of the 18 strains excluding the 11 ST398 strains exhibited a maximum of 100% homology and a minimum of 64.0% homology. Among these, three pairs of isolates showed 100% homology in PFGE; these results were consistent with the MLST and spa typing results. Identification of MRSA at the final consumption stage has potential risks, suggesting that continuous monitoring of retail meat products is required.

• 한국식품과학회지
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• 제30권4호
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• pp.916-923
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• 1998

인체장염 유발균으로 최근 문제가 되고 있는 미호기성 식중독균 Campylobacter jejuni의 오염 방지와 식품 속에서의 검출을 위한 실험으로서 두종의 인체 유래 C. jejuni를 이용하여 증균 선택배지에서의 증식과 우유, 닭고기등에서의 첨가 후의 잔존 양상을 온도별로 조사하였다. C. jejuni는 Supplemented Brucella Broth (SBB)에서 호기적 조건에서도 최적조건인 미호기적 배양에 비해 $60{\sim}80%$ (24시간)의 생육이 관찰되었다. SBB에 C. jejuni를 생균수가 $10^7{\;}cfu/mL$과 $10^3{\;}cfu/mL$ 되도록 접종하여 호기조건에서 42, 25, $5^{\circ}C$에서 7일간 배양하였을 때 $42^{\circ}C$에서는 $10^7{\;}cfu/mL$과 $10^3{\;}cfu/mL$ 접종시료 모두 $1{\sim}2$일 후 $>10^8$으로 급격히 증가하다가 7일에는 $>10^7$으로 유지되었다. $5^{\circ}C$에서는 배양 초기 접종된 량을 거의 유지하다가 7일 경과후에 $<1/2log_{10}$ 정도가 감소하였다. $25^{\circ}C$에서는 $1{\sim}2$일 이 후 급격히 감소하여 4일 이 후에는 균이 거의 검출되지 않는 수준이었다. 가열 처리된 우유와 잘게 썰은 닭고기에 $10^7/mL$ 되도록 균을 접종한 후 42, 25, $5^{\circ}C$에서 14일간의 생균수의 변화를 조사한 결과, 우유에서는 SBB에서와 유사한 결과를 보였고, 닭고기에서는 $42^{\circ}C$의 최적조건에서 4일 이후 균이 검출되지 않아 균의 생육이 유지된 $4^{\circ}C$의 냉장조건과 대조를 이뤘다. 이상의 결과에 의하여 C. jejuni가 오염된 식품이 유통되고 취급될 때 냉장온도에서 가장 그 생육이 안정하게 보존되며, 실온에서는 생육이 불안정하여, 식품에 따라 최적 온도에서도 생육 양상이 다르다는 것을 알 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제20권4호
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• pp.569-576
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• 2007

Four hundred and fifty tilapias ($6.77{\pm}0.23$ g) were assigned randomly to six groups to evaluate the feasibility of the tested antibacterial peptides (ABPs) and oligosaccharides as substitutes for antibiotics. The control group was fed with a commercial tilapia diet; other five groups were fed with the same commercial diet supplemented with konjac glucomannan (KGLM), cluster bean galactomannan (CBGAM), and three animal intestinal ABPs derived from chicken, pig and rabbit at 100 mg/kg respectively. After 21 days of feeding, growth, disease resistance, and in vivo anti-adherence were determined. Furthermore, the inhibitory effect of tested agents on adhesion of Aeromonas veronii biovar sobria (A.vbs) strain BJCP-5 to tilapia enteric epithelia in vitro was assessed by cell-ELISA system. As a result, the tested agents supplemented at 100 mg/kg show significant benefit to tilapia growth and disease resistance (p<0.05), and the benefit may be correlated with their interfering in the contact of bacteria with host mucosal surface. Although none of the tested agents did inhibit the growth of BJCP-5 in tryptic soy broth at $100{\mu}g/ml$, all of them did inhibit the adhesion of A.vbs to tilapia enteric epithelia in vivo and in vitro. In vitro mimic assays show that three ABPs at low concentrations of $25{\mu}g/ml$ and $2.5{\mu}g/ml$ have the reciprocal dose-dependent anti-adherence effect. The inhibition of ABPs may be correlated with a cation bridging and/or receptor-ligand binding, but not with hydrophobicity. The KGLM and CBGAM inhibited the adherence of BJCP-5 to tilapia enteric epithelia with dose-dependent manner in vitro, and this may be through altering bacterial hydrophobicity and interfering with receptor-ligand binding. Our results indicate that the anti-adherence of the tested ABPs and oligosaccharides may be one of the mechanisms in promoting tilapia growth and resistance to A.vbs.

• 한국식품위생안전성학회지
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• 제24권4호
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• pp.385-390
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• 2009

This survey was conducted to monitor the total sugar, sodium, and artificial sweetener contents of light meals from the school zone in Gwangju, from November, 2008 to April, 2009. A total of 100 samples were tested. HPLC/ELSD was used for the determination of total sugar contents and AAS for sodium contents. Total sugar amounts were the sum of both mono-and disaccharide according to nutritional information standard defined by the Korea Food and Drug Administration. The results were as follows by the form of total sugar content(sodium content): $5.7\;{\pm}\;1.9%$($4.6\;{\pm}\;1.6\;mg/g$) for Tteokbokki, $7.6\;{\pm}\;5.1%$($5.4\;{\pm}\;2.7\;mg/g$) for Chicken(skewed), $15.4\;{\pm}\;3.2%$($3.0\;{\pm}\;0.9\;mg/g$) for Bun(fish-shaped), $0.6\;{\pm}\;0.3%$($3.7\;{\pm}\;1.0\;mg/g$) for Sundae, $0.9\;{\pm}\;0.3%$($7.4\;{\pm}\;1.4\;mg/g$) for Oden(with broth), $20.5\;{\pm}\;6.2%$($2.9\;{\pm}\;0.6\;mg/g$) for Waffle, $6.8\;{\pm}\;2.2%$($4.7\;{\pm}\;1.0\;mg/g$) for Hotdog, $14.2\;{\pm}\;2.8%$($3.1\;{\pm}\;1.6\;mg/g$) for Hotteok, $6.6\;{\pm}\;2.1%$($3.9\;{\pm}\;0.6\;mg/g$) for Toast, $10.1\;{\pm}\;3.7%$($2.3\;{\pm}\;0.7\;mg/g$) for Fry(sweet potato), $1.6\;{\pm}\;0.7%$($4.0\;{\pm}\;0.7\;mg/g$) for Fry(etc), and $9.3\;{\pm}\;2.4%$($4.0\;{\pm}\;0.6\;mg/g$) for Doughnut. In addition, sodium saccharin, one of the artificial sweeteners, was tested. Among 60 samples from February to April, 2009, 11 samples had sodium saccharin(6.7~101.0 mg/kg).

• 대한지역사회영양학회지
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• 제8권6호
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• pp.901-909
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• 2003

This study was conducted to devise a scheme for the development of foods designated as Yookmee (“6 dishes), which are representative food of Daejeon area. The Yookmee consist of Seolleongtang(ox bone soup and boiled rice), Samgyetang (chicken stew stuffed with glutinous rice and ginseng), Dolsotbap (boiled rice mixed with vegetables), Goojeukmook (acorn jelly), Sootgol-naengmyeon (cold buckwheat noodles with broth) and Daecheongho minmulgogi-maeuntang (spicy hot freshwater fish soup). A questionnaire was developed and administered by means of an interview regarding the subjects' recognition of and preference for the six dishes, their usual eating places and eating frequencies, the need for some standardization of recipes and for nutrition labeling including serving sizes and nutrient content. The total number of subjects who participated in this study were 328 (male 112, female 216) living in Daejeon. The subjects who were aware of the presence of Yookmee were more in their thirties or older (15%) compared to those in their twenties (9.6%) The percentages of the subjects who recognized the Yookmee as the representative foods were twice among those in their thirties (over 60%), as compared to 31.5% in their twenties (p<0.001). Samgyetang was one of the favorite foods of all the Yookmee among those in their twenties and Goojeukmook was the favorite for all the other age groups. The incidence of those eating one of Yookmee more than once a month was 51.5% in all the age groups, but the intake frequency was lower among those in their twenties (43.8%). The percentage of those who recommended Yookmee as a food for guests was the highest among those in their fifties (54.7%). The first reason why the subjects do not recommend these foods was because they were unfamiliar with Yookmee; among those in their thirties and forties the 2nd reason was because it is not much enough in quality or quantity to be served as a food for guests. Over 60% of the subjects felt the need for standardization of Yookmee, recipes for especially those in their fifties did feel the needs (92.5%). Furthemore, regarding labeling of sowing sizes and nutrients contents, over 80% of the subjects wanted these, and this desire tended to increase with age. From these results, it seems reasonable to accept Yookmee as the representative foods of Daejeon, despite the fact that many people do not yet currently do so. Since most of the subjects (85.4%) partake Yookmee outside of their homes, it is recommended that efforts need to be expanded on enhancing the nutritional quality, the taste and the quality control of Yookmee by standardizing the recipes, labeling the serving sizes and nutrient contents, and providing educational and publicity programs.

• 생명과학회지
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• 제16권1호
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• pp.22-29
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• 2006

유기물이 풍부한 토양에서 분리하여 동정한 Bucillus stearothermophilus DL-3균주의 배양액과 사과박, 간장박 및 미강 등을 사용하여 2종류의 미생물 제재를 제조하고 닭과 돼지의 생육에 미치는 영향을 조사하였다. 사과박의 주성분은 탄수화물이며 간장박의 주성분은 단백질이다. B. stearothermophilus DL-3 균주의 배양액과 미강을 사용하여 제조한 미생물 제제를 미생물 제제 A로 명명하고 B. stearothermophilus DL-3균주의 배양액, 사과박, 간장박 및 미강을 사용하여 제조한 미생물 제제를 미생물 제제 B로 명명하였다. 미생물 제재가 닭 및 돼지의 생육에 미치는 영향을 검토하기 위하여 일반사료를 급여한 구, 일반사료의 $10\%$를 미생물 제재 A로 대체하여 급여한 구 및 일반사료의 $10\%$를 미생물 제재 B로 대체하여 급여한 구로 나누어 효과 검정실험을 수행하였다. 실험에 사용한 각 구의 평균 병아리 무게는 각각 $41.1{\pm}2.5g,\;41.6{\pm}3.2g$ 및 $42.3{\pm}2.9g$이었다. 급여를 시작하지 28일 후, 각 구에 속한 병아리들의 평균 무게는 각각 $547.7{\pm}91.7g,\;560.1{\pm}17.2g$ 및 $562.2{\pm}32.5g$이었으며 각 구에 속한 병아리들의 평균 무게 증가는 각각 506.6 g, 518.5 g 및 519.9 g이었다. 즉, 일반사료의 $10\%$를 미생물 제재 A로 대체하여 급여한 군과 일반사료의 $10\%$를 미생물 제재 B로 대체하여 급여한 군은 일반사료를 급여한 군에 비하여 각각 $2.4\%$ 및 $2.6\%$의 무게 증가를 나타났다. 각 구의 평균 돼지 무게는 각각 $9.3{\pm}1.0kg,\;9.4{\pm}1.1kg$ 및 $9.6{\pm}1.0kg$이었다. 급여를 시작한지 35일 후, 각 구에 속한 돼지들의 평균 무게는 각각 $19.3{\pm}4.1kg,\;20.2{\pm}3.9kg$ 및 $20.8{\pm}4.2kg$이었으며 각 구에 속한 돼지들의 평균 무게 증가는 각각 10.7 kg, 10.8 kg 및 11.2 kg이었다. 닭의 사료 효과 검정 결과와 같이 일반사료의 $10\%$를 미생물 제재 A로 대체하여 급여한 군과 일반사료의 $10\%$를 미생물 제재 B로 대체하여 급여한 군은 일반사료를 급여한 군에 비하여 각각 $1.6\%$ 및 $5.2\%$의 무게 증가를 나타났다.