현재 대부분의 수삼은 흙이 묻은 상태로 유통되고 있는데 소비자의 편이성을 고려하여 수삼을 세척한 후 포장한 상태로 유통시키기 위한 연구의 일환으로 수삼의 세척처리 방법에 따른 표면세척효과 및 미생물 감균 효과를 조사하였다. 수확 직후 수삼의 부위별 생균수는 5.85~6.63 log CFU/ea범위로 뇌두 부위가 가장 많았고 다음으로는 지근과 주근 순이었다. 부위별 곰팡이 수는 3.67~5.12 log CFU/ea범위로 뇌두 부위가 많았으며 주근과

한국원자력연구원 지하처분연구시설의 지하심부에 생존하는 미생물을 이용하여 용존우라늄의 제거 및 광물화에 대한 실험을 실시하였다. 미생물은 철환원박테리아와 황산염환원박테리아로 구분하여 개별적으로 실험을 실시하였으며, 실험 후 X-선 회절분석 및 주사전자현미경을 이용하여 생성광물을 확인하였고 용액상의 농도 변화는 유도결합플라즈마분석기를 이용하여 분석하였다. 철환원박테리아에서는 우라늄과 철이온이 공존할 때, 우라늄보다는 철이온이 선택적으로 환원과정에 참여하였으며, 결과적으로 우라늄의 환원 및 제거가 거의 이루어지지 못하였다. 하지만, 망간이 포함된 조건에서는 상당량의 우라늄 제거 효과가 나타났다. 황산염환원박테리아에서는 철과 망간이 공존할 때, 철이 선택적으로 황과 결합하여 맥키나와이트(FeS)라는 황화광물을 형성하였으며, 망간으로 구성된 황화광물은 만들어지지 않았다. 하지만, 망간이 공존하는 경우에 우라늄의 제거는 훨씬 효과적이었는데, 이는 황화광물에 불순물로 포함된 망간이 우라늄의 흡착 및 포획에 큰 영향을 미치기 때문인 것으로 판단된다.

The objectives of this research are to evaluate and compare the oxygen transfer coefficients(KLa) in both a general bubbles reactor and a micro-nano bubbles reactor for effective operation in sewage treatment plants, and to understand the effect on microbial kinetic parameters of biomass growth for optimal biological treatment in sewage treatment plants when the micro-nano bubbles reactor is applied. Oxygen transfer coefficients(KLa) of tap water and effluent of primary clarifier were determined. The oxygen transfer coefficients of the tap water for the general bubbles reactor and micro-nano bubbles reactor were found to be 0.28 hr -1 and 2.50 hr -1 , respectively. The oxygen transfer coefficients of the effluent of the primary clarifier for the general bubbles reactor and micro-nano bubbles reactor were found be to 0.15 hr -1 and 0.91 hr -1 , respectively. In order to figure out kinetic parameters of biomass growth for the general bubbles reactor and micro-nano bubbles reactor, oxygen uptake rates(OURs) in the saturated effluent of the primary clarifier were measured with the general bubbles reactor and micro-nano bubbles reactor. The OURs of in the saturated effluent of the primary clarifier with the general bubbles reactor and micro-nano bubbles reactor were 0.0294 mg O2/L․hr and 0.0465 mg O2/L․hr, respectively. The higher micro-nano bubbles reactor's oxygen transfer coefficient increases the OURs. In addition, the maximum readily biodegradable substrate utilization rates(Kms) for the general bubbles reactor and micro-nano bubbles reactor were 3.41 mg COD utilized/mg active VSS․day and 7.07 mg COD utilized/mg active VSS․day, respectively. The maximum specific biomass growth rates for heterotrophic biomass(μmax) were calculated by both values of yield for heterotrophic biomass(YH) and the maximum readily biodegradable substrate utilization rates(Kms). The values of μmax for the general bubbles reactor and micro-nano bubbles reactor were 1.62 day -1 and 3.36 day -1 , respectively. The reported results show that the micro-nano bubbles reactor increased air-liquid contact area. This method could remove dissolved organic matters and nutrients efficiently and effectively.

본 연구에서는 계육 창상부위의 원인이 되는 세균을 동정하였다. 계육의 등과 다리 창상 부위로부터 무작위 선별법을 통해 총 10주의 균주를 분리하였다. 순수 분리 배양된 균주의 세포막 지방산 조성 분석 결과, 5 균주가 높은 유효성을 지녔으며, Shigella sonnei, Proteus mirabilis, Escherichia coli로 동정되었다. 또한 16S rRNA sequence를 실시한 결과, 동정된 균주는 Shigella sonnei(

쌀겨의 발효는 온도상승이 되면서 열을 많이 발생하여 온도가 60-70도로 상승한다. 이 발효에서 분리된 Bacillus coagulans는 효소온욕시 사용되는 주요 미생물로서, 이를 응용하여 피부미용건강에 사용되어질 수 있다. 쌀겨발효 중 온도유지에 관련이 있는 major microflora의 분리 연구를 수행한 결과, 고초균이라 판단되는 균주 10여종을 분리하였으며 이를 분자분류학적인 연구를 수행한 결과 Bacillus coagulans로동정하

To understand the initial changes in the microbial activities of wetland soil after construction, dehydrogenase activity (DHA) and denitrification potential (DNP) of soil from 1 natural wetland and 2 newly constructed wetlands were monitored. Soil samples were collected from the Daepyung marsh as a natural wetland, a treatment wetland in the West Nakdong River, and an experimental wetland in the Pukyong National University, Busan. The results showed that the DHA of the natural wetland soil was 6.1 times higher than that of the experimental wetland and similar to that of the treatment wetland 6 months after wetland construction (fall). Few differences were observed in the DNP between the soil samples from the natural wetland and 2 constructed wetlands four months after wetland construction (summer). However, 6 months after the construction (fall), the DNP of the soil samples from the natural wetland was 12.9 times and 1.8 times higher than that of the experimental wetland and the treatment wetland, respectively. These results suggested that the presence of organic matter as a carbon source in the wetland soil affects the DHA of wetland soil. Seasonal variation of wetland environment, acclimation time under anaerobic or anoxic wetland conditions, and the presence of carbon source also affect the DNP of the wetland soil. The results imply that the newly constructed wetland requires some period of time for having the better contaminant removal performance through biogeochemical processes. Therefore, those microbial activities and related indicators could be considered for wetland management such as operation and performance monitoring of wetlands.

이산화염소수 또는 푸마르산이 전처리된 고추, 생강, 당근의 초기 미생물수 감소 효과에 관한 연구를 하기 위하여 이산화염소수 5, 10, 50 ppm과 푸마르산 0.1, 0.3, 0.5%를 고추, 생강, 당근에 5분간 각각 처리하였다. 이산화염소수와 푸마르산 전처리는 총균수, 효모와 곰팡이 수를 유의적으로 감소시켰는데, 특히 50 ppm의 이산화염소수를 고추에 처리 시 총균수, 효모 및 곰팡이 수가 1.52, 1.81 log CFU/g 감소시킨 반

건강 웰빙식품의 하나로서 수요가 증가하고 있는 새싹채소류는 미생물학적 관점에서 생산단계별 위해분석과 안전성 기준이 부재한 실정이다. 본 연구에서는 생산현장에서 새싹채소의 재배공정별 미생물학적 오염도를 분석 평가하였다. 새싹채소 종자의 일반세균수 및 대장균군수는 각각 3.04~5.21 log CFU/g, 1.80~3.86 log CFU/g의 범위로 나타났으며, 소독유무에 관계없이 재배기간 동안 일반세균(6.99~8.26 log CFU/g) 및 대장

The potential of encapsulated inuloprebiotics from domestic Jerusalem artichokes (Helianthustuberosus) as natural antibacterial growth promotor for an antibiotic replacement in broiler chickens was presently assessed through assays of growth performance, serum immunoglobulin production and influence on caecal microflora. Two hundred-forty, 1-day-old, male broilers (Ross 308) were randomly allotted to four treatments (T1–T4), with three replicate pens per treatment and 20 chicks per pen. Broiler chicks were fed a basal diet (T1: control) or basal diet plus antibiotics (T2: Chlorotetracycline, 0.10%), 300 ppm of the inuloprebiotics (T3), or 450 ppm of the inuloprebiotics (T4) for 35 days. Body weight, dressing percentage or weight of breast and thigh muscles relative to carcass weight of T3 and T4 broiler chickens was significantly (P＜0.05) higher than T1 and T2 broiler chickens. The weight of abdominal fat from T3 and T4 broiler chickens were significantly (P

Microbial contamination levels in a fresh-cut leafy vegetable processing plant were evaluated. Total plate counts of samples collected from the walls, equipment, and raw materials ranged from CFU/100 , CFU/100 , and CFU/g, respectively. No coliforms were detected on walls; however, equipment and raw materials contained coliforms in concentrations ranging from ND (not detected)to CFU/100 and CFU/g, respectively. Additionally, total plate counts for falling and floating bacteria in the processing plant were CFU/plate and , respectively. Pathogenic microorganisms such as Escherichia coli, Salmonella spp, Staphylococcus aureus, or Listeria monocytogenes were not detected on walls, equipment, or raw materials. Overall, the results of this study indicate that hygiene control in the fresh-cut processing plant should be improved.

We evaluated the microbiological quality of a facility in which freshly cut onions were prepared. The total plate counts on walls, equipment, and raw materials were ND (not detected) to CFU/100 , CFU/100 , and CFU/g, respectively. No coliforms were detected on walls however, coliforms were detected at concentrations of ND to CFU/100 and CFU/g on equipment and raw materials, respectively. The total plate counts for falling and floating bacteria in the processing plant were ND to CFU/plate and , respectively. Pathogenic microorganisms such as Escherichia coli, Salmonella spp, Staphylococcus aureus, and Listeria monocytogenes were not detected on walls, equipment, or raw materials. Overall, the results of the study indicate that hygiene control at the fresh-cut processing plant should be improved.

Response surface methodology (RSM) is frequently used for optimization studies. In the present work, RSM was used to determine the antimicrobial activitiesof grapefruit seed extract (GFSE) and a lactic acid mixture (LA) against Staphylococcus aureus, Bacillus cereus, Escherichia coli, Salmonella typhimurium, Pseudomonas fluorescens, and Vibrio parahaemolyticus. A central composite design was used to investigate the effects of independent variables on dependent parameters. One set of antimicrobial preparations included mixtures of 1% (w/w) GFSE and 10% (w/w) LA, in which the relative proportions of component antimicrobials varied between 0 and 100%. In further experiments, the relative proportions were between 20% and 100%. Antimicrobial effects against various microorganisms were mathematically encoded for analysis. The codes are given in parentheses after the bacterial names, and were S. aureus (), B. cereus (), E. coli (), S. typhimurium (), P. fluorescens (), and V. parahaemolyticus (). The optimum antimicrobial activity of the 1% (w/w) GFSE:10% (w/w) LA mixture against each microorganism was obtained by superimposing contour plots ofantimicrobial activities on measures of response obtained under various conditions. The optimum rangesfor maximum antimicrobial activity of a mixture with a ratio of 1:10 (by weight) GFSE and LA were 35.73:64.27 and 56.58:43.42 (v/v), and the optimum mixture ratio was 51.70-100%. Under the tested conditions (a ratio of 1% [w/w] GFSE to 10% [w/w] LA of 40:60, and a concentration of 1% [w/w] GFSE and 10% [w/w] LA, 70% of the highest value tested), and within optimum antimicrobial activity ranges, the antimicrobial activities of the 1% (w/w) GFSE:10% (w/w) LA mixture against S. aureus (), B. cereus (), E. coli (), S. typhimurium (), P. fluorescens (), and V. parahaemolyticus () were 24.55, 25.22, 20.20, 22.49, 23.89, and 28.04 mm, respectively. The predicted values at optimum conditions were similar to experimental values.

Trickling filter has been extensively studied for the domestic wastewater treatment especially for the small scale plants in rural area. The performance of the trickling filter depends on the microbial community and their activity in the biofilms on the media. Nitrification, denitrification, and phosphorus removal of the trickling filter from the wastewater depend on the activity and the amount of the specific microorganisms responsible for the metabolism. For the estimation of the performance of a trickling filter, batch nitrification experiment and fluorescence in situ hybridization (FISH) were carried out to measure the microbial activity and its distribution on the media of the trickling filter. Batch nitrification activity measurement showed that the top part of the 1st stage trickling filter had the highest nitrification activity and the maximum activity was 0.002 g NH4-N/g MLVSS․h. It is thought that higher substrate (ammonia) concentration yields more nitrifying bacteria in the biofilms. The dominant ammonia oxidizer and nitrite oxidizer in the biofilm were Nitrosomonas species and genus Nitrospira, respectively, by FISH analysis. Less denitrifiers were found than nitrifiers in the biofilm by the probe Rrp1088 which specifically binds to Rhodobacter, Rhodovulum, Roseobacter, and Paracoccus. Phosphorus accumulating bacteria were mostly found at the surface of the biofilm by probe Rc988 and PAO651 which specifically binds to Rhodocyclus group and their biomass was less than that of nitrifiers.

녹차는 생리활성의 촉진작용뿐아니라 항암, 항산화, 고혈압 억제효과, 체중조절 등 다방면의 약리효과를 보이는 것으로 보고되고 있다. 아울러, 녹차의 항균 및 항진균 작용에 관한 연구결과도 발표되고 있으나, 항균작용 기작에 접근한 기초 연구는 별로 많지 않다. 본 연구는 식품변패미생물에 대한 녹차추출물의 항균작용을 구명하는 기초자료를 획득하는데 그 목적이 있다. 녹차추출물의 항균력을 조사한 결과, 이상의 농도에서 뚜렷한 항균활성을 보였고, 광역의

본 연구에서는 새싹종자 소독처리 여부에 따른 재배기간별 미생물 오염도 수준을 파악하고, 종자소독이 발아율에 미치는 영향을 분석하였다. 수입산 새싹종자 알팔파(alfalfa), 브로콜리(broccoli), 클로버(clover), 적양배추(red cabbage), 적무(red radish) 5종에 대하여 소독제 처리 여부에 따른 발아율과 재배기간별 미생물 분석을 실시하였다. 소독제 종류에 관계없이 새싹종자(알팔파, 클로버, 적무)는 48시간 후 90

수산 가공 부산물인 자숙액을 식품 및 공중보건 소재로 이용하기 위해 자숙액의 위생화를 위한 감마선 조사기술의 이용가능성을 검토하였다. 톳, 참치 및 굴 자숙액을 시료로 하여 1-5 kGy의 감마선을 조사하여 미생물 생존율을 측정하였고 생존미생물을 동정하였다. 굴 자숙액에서는 호기성 미생물이 검출되지 않았으나, 톳 및 참치 자숙액에서는 약 6.4 및 3.1 log CFU/g의 호기성 미생물이 검출되었고, 저장기간이 증가함에 따른 미생물 수에는 유의

이 연구의 목적은 대구 경북지역 초등학교에 공급되는 냉장, 냉동유통 제품인 어육류와 냉동가공제품의 유통단계를 분석하고, 유통과정에서의 미생물 변화와 학교급식에 이용되는 식재료의 미생물 품질 평가를 위하여 실시되었다. 쇠고기와 돼지고기는 가공업체에서 학교로 냉동차량을 이용하여 직배송 되었으나 다른 어육류와 냉동가공제품들은 농산물과 함께 직납업체를 거쳐 냉장()으로 혼재 배송되고 있었다. 학교 도착 후 일반세균과 대장균군의 수는 각각 절단생선 ,