• Journal of Microbiology
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• 제42권4호
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• pp.315-318
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• 2004

This study was undertaken to determine the suitability of tomato juice as a raw material for production of probiotic juice by four lactic acid bacteria (Latobacillus acidophilus LA39, Lactobacillus plantarum C3, Lactobacillus casei A4, and Lactobacillus delbrueckii D7). Tomato juice was inoculated with a 24­h-old culture and incubated at $30^{\circ}C$. Changes in pH, acidity, sugar content, and viable cell counts dur­ing fermentation under controlled conditions were measured. The lactic acid cultures reduced the pH to 4.1 or below and increased the acidity to $0.65\%$ or higher, and the viable cell counts (CFU) reached nearly 1.0 to $9.0\times10^9/ml$ after 72 h fermentation. The viable cell counts of the four lactic acid bacteria in the fermented tomato juice ranged from $10^6\;to\;10^8\;CFU/ml$ after 4 weeks of cold storage at $4^{\circ}C$. Pro­biotic tomato juice could serve as a health beverage for vegetarians or consumers who are allergic to dairy products.

• 농업과학연구
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• 제38권3호
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• pp.485-491
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• 2011

Yogurt was prepared from skim milk added with 2, 4 or 6% of green whole grain of barley, wheat, glutinous rice and common rice, respectively. Changes in pH, titratable acidity, viable cell counts and viscosity during fermentation were monitored and its sensory evaluation was also performed. The optimum level of additives such as green whole grain of barley, wheat, glutinous rice and common rice for yogurt manufacture was selected to 2%. The samples added with green whole grain of barley and wheat powders reached pH 4.5 in 12 hours. After 4 hours of fermentation, pH, the viable cell counts and viscosity in samples added with 2% green whole grain of barley, wheat, glutinous rice and common rice powders were the highest. Especially, in overall sensory evaluation using 5 parameters, the sensory scores of glutinous rice and common rice 2% yogurts were significantly high. From this experiment, the additives optimum level of glutinous rice and common rice powders was selected to be 2%.

• 한국식품위생안전성학회지
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• 제1권1호
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• pp.47-50
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• 1986

Sanitary condition for raw milk in Korea was investigated in this study. It is hoped that the information will be used for reference in future endeavors of study in the field of public health and food sanitation in Korea. The results were summerized as follows: 1) The viable cell counts of bacteria in raw milk were tend to be increased under the various atmospheric temperature, and the correlation coefficient between temperature and total viable cells was r=+0.921(p<0.01). 2) The correlation coefficient between methylene blue reduction time test and viable cell counts of bacteria in raw milk was r=-0.799(p<0.01). 3) The relationship between total solid rate(%) and milk fat rate(%) was highly significant level as r=+0.745(p<0.01). 4) Highly significant correlation coefficient was r= +0.945(p<0.01) between milk fat and protein rate in raw milk.

• 한국식품영양과학회지
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• 제39권6호
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• pp.864-871
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• 2010

흰 마늘/흑 마늘 첨가에 따른 김치 젖산균을 이용한 발효물을 제조하여 품질 및 기능성 평가를 수행하였다. 고형분 함량은 17% 흰 마늘 습식분쇄물과 22.63% 흑 마늘 습식분쇄물이다. 마늘 혼합물에 Leuconostoc mesenteroides 균주를 이용하여 24시간 동안 젖산 발효시킨 발효물의 생균수와 점도는 흑 마늘의 첨가농도가 증가함에 따라 감소하였으며, 흑 마늘을 10% 수준으로 첨가한 경우에 생균수는 $1.6\times10^{11}$ cfu/mL, 점도는 9.31 $Pa{\cdot}s^n$를 나타내었다. 마늘 발효물의 물과 70% EtOH 추출물의 polyphenol 함량은 각각 6.29 mg/mL, 5.99 mg/mL이며, DPPH 소거 활성은 $IC_{50}$ 값이 1.03 mg/mL, 1.07 mg/mL, ACE 저해 활성의 $IC_{50}$값은 68.54 mg/mL과 72.78 mg/mL이다. ACE 저해활성은 흑 마늘이 많이 첨가될수록 높게 나타났으며 그중에서 70% EtOH 추출보다 물 추출에서 높은 활성을 나타내는 것으로 나타났다. 마늘 발효물의 sucrose 전환율은 흑 마늘 첨가 농도가 낮을수록 급격하게 증가하면서 흑 마늘 20%, 10%, 0% 첨가에서 각각 20%, 65%, 85%를 보였다. 흑 마늘 10% 함유 발효물의 저장 중 점도는 완만하게 감소하였으며, 생균수는 냉장저장 1주 후 $1.6\times10^{11}$ cfu/mL에서 $6.5\times10^{10}$ cfu/mL로 감소하였으며, 냉동저장이 냉장저장보다 높은 생균수를 나타내었다.

• 한국축산식품학회지
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• 제21권2호
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• pp.133-141
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• 2001

Adherence of probiotic bacteria to intestinal epithelium is found to be the most principal characteristics among the various physiological functionality. This study was conducted to investigate the effect of bifidobacterial growth properties and condition on the Caco-2 cell adherence and to construct a basic data on adherence-related research. Among 20 strains of bifidobacteris tested, when measured by cell surface hydrophobicity(CSH) and cell agglutination(CA), Bifidobacterium bifidum ATCC29521, Bif. adolescentis K8, and Bif. infantis K9 were selected. Using these strains, variations of Caso-2 cell adherence depending upon experimental condition were analyzed. The results obtained are as follows : Even though Bif. bifidum ATCC29521, Bif. adolescentis K8, and Bif. infantis K9 reached more 85% cell surface hydrophobicity there was no significant difference in cell agglutination, when reached 31.54$\pm$0.54mg/ml. By direct count method for adherence, viable cell count of M3, K1, K2, K8, K9 and K10 reached more 100 counts per 100 Caco-2 cells. When Bif. bifidum ATCC29521, Bif. adolescentistis K8, and Bif. infantis K9 were used to compare the adherence depending upon viable cell counts, reaction time, and growth phase, the more viable cell count, and the more adhered cell counts, the less adherence percentage. In addition, there was no difference in adherence percentage of bifidobacteria when bifidobacteria was incubated from 1 to 8 hrs after Caco-2 cells already formed monolayer. Considering of the effect of growth phase of bifidobacteria on adherence variation, all strains showed the highest adherence during the early stage of stationary phase. In conclusion, adherence of bifidobacteria was affected by strain specificity, viable cell count, and growth activity.

• 한국식품영양학회지
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• 제21권2호
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• pp.176-183
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• 2008

This study examined the anti-microbiological effects of chlorine treatment on the surface of fresh fruits, in order to improve microbiological safety in school foodservice operations. Non-peeled fruit(strawberries) and peeled fruit(bananas) were treated with different concentrations of chlorinated water and rinsing numbers, followed by microbiological testing. The fruits were immersed at different concentrations of chlorinated water(0 ppm, 50 ppm, and 100 ppm) and durations(3 min and 5 min), and were then rinsed with tap water(one time, two times, or three times). The total viable cell counts of both the strawberries and bananas ranged from $10^3$ CFU/g to $10^4$ CFU/g, and coliform levels ranged from $10^2$ CFU/g to $10^3$ CFU/g. As the chlorine concentration, immersion time, and rinsing number increased, anti-microbiological activity increased. The largest microbial reduction was shown with immersion for 5 min in 100 ppm chlorinated water and three rinsings. In the strawberries, this treatment reduced the initial population of total viable cells and coliforms by 3.29 log CFU/g and to an undetectable level, respectively, no total viable cells or coliforms were detected on the banana surface following this treatment. However, after a sterilization treatment with immersion for 5 min in 50 ppm chlorinated water and three rinsings, the total viable cell counts and coliform counts of the strawberries and bananas decreased to acceptable levels, based on the microbiological standards for ready-to-eat foods. Overall, it was shown that the sterilization treatment of 50 ppm chlorinated water, soaking for 5 min, and three rinsings provided an effective reduction in surface microbes, and enhanced the microbiological safety of the fruit.

• 한국균학회지
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• 제39권2호
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• pp.151-153
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• 2011

한국 전통 생 막걸리의 최적 저장 조건을 확립하기 위하여 먼저 전통 생 막걸리를 제조한 후 $4^{\circ}C$와 $20^{\circ}C$에 저장하면서 효모와 총 세균, 젖산균 수의 변화를 조사하였다. 효모는 $20^{\circ}C$에서 30일 저장 후 89%가 감소 되었으나, $4^{\circ}C$저장에서는 큰 변화가 없었다. 총 세균수는 $20^{\circ}C$에서 30일 저장시 98.0%가 감소 되었고 젖산균 역시 99%가 감소되었다. 그러나 $4^{\circ}C$저장에서는 65%미만의 낮은 감소를 보였다. 위의 결과와 관능검사 결과 등을 종합하였을 때 본 연구에서 제조한 생 막걸리는 $4^{\circ}C$와 $20^{\circ}C$에서 15일까지도 큰 품질저하 없이 음용할 수 있는 상태로 저장이 가능한 것으로 판단된다.

• 대한의생명과학회지
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• 제22권4호
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• pp.215-219
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• 2016

The problems of tuberculosis and its drug resistance are very severe. Therefore, rapid and accurate drug susceptibility assay is required. Recently, there has been an increased understanding of the genetic mechanism of Mycobacterium tuberculosis (MTB) drug resistance as well as advancement of molecular technologies. While many gene mutations correlate well with drug resistance, many genes do not show a strong correlation with drug resistance. For this reason, the current study assessed the utility of rpoB mRNA as a target to detect live mycobacteria. In this study, RT-PCR targeting of rpoB mRNA in BCG treated with rifampin was performed. Conventional RT-PCR and real-time PCR targeting rpoB mRNA as well as 85B mRNA was performed to determine whether these two methods could distinguish between viable and non-viable MTB. The levels of rpoB and 85B mRNA detected by RT- PCR were compared in parallel with colony forming unit counts of BCG that were treated with rifampin for different periods of time. The data suggests that that even though both mRNA levels of rpoB and 85B decreased gradually when rifampin-treatment increased, the rpoB mRNA seemed to represent live bacteria better than 85B mRNA. This study clearly indicates that RT-PCR is a good method to monitor viable cell counts in the liquid culture treated with the anti-tuberculosis drug.

• 한국식품영양학회지
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• 제13권1호
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• pp.71-77
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• 2000

New type yogurt base were prepared from milk added with skim milk powder or purple sweet potato, and fermented by lactic acid bacteria (Streptococcus thermophilus and Bifidobacterium infantis, 1:1, v/v). The yogurt proudcts were evaluated for acid production(pH, titratiable acidity), number of viable cell, viscosity, sensory properties, and color value. The composition of some organic acids was also analyzed by GC. The acid production slightly decrerased by addition with purple sweet potato. There was no significant difference in viable cell counts between control (yogurt added with only skim milk powder) and yogurt added with purple sweet potato, and viable cell counts of all samples were above 9.08 log cfu/ml. Viscosity of yogurt added with purple sweet potato(36,800∼46,000 centipoise) was higher than that of yogurt added with only skim milk powder(32,200 centipoise). The overall sensory score of yogurt added with purple sweet potato(38.6%, dry base) was the best of tested yogurt. The major organic acid of yogurt added with purple sweet potato was lactic acid. its content was 0.997∼1.203%. malic acid, succinic acid, oxalic acid, and fumaric acid were analyzed out a little. Lightness and yellowness decreased by addition with purple sweet potato but redness increased. Total color difference($\Delta$E) with yogurt addition with purple sweet potato and only skim milk powder were very high(above 11.46).

• 환경생물
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• 제26권3호
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• pp.247-251
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• 2008

통영, 인천, 군산 및 홍성의 해수 미생물에서 각종 어업용구의 재료로 사용될 수 있는 Mater-Bi$^{(R)}$, PHBV, PBSA 및 PCL의 분해거동을 조사하였다. Acinetobacter lwoffu/junii와 Shewanella algae/putrefaciens는 모든 해수속에 서식하고 있었으며 Eikenella corrodens 역시 비록 YITEK 결과의 신뢰도가 조금 낮은 수준으로 동정되었지만 모든 해수에서 검출되었다. 해수에서는 Mater-Bi$^{(R)}$가 PHBV, PBSA및 PCL보다 더 빠르게 분해되어 토양 환경에서의 분해와는 다른 거동을 나타내었다. 인천의 해수가 이들 플라스틱에 대하여 가장 높은 분해활성을 보였으며 이는 인천의 해수가 가장 많은 수의 total viable count를 포함하고 있는데 일부 기인하는 것으로 사료된다.