• 한국조리학회지
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• 제21권6호
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• pp.195-205
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• 2015

본 연구는 고추씨 분말을 부재료로 이용하여 0%, 10%, 20%, 30% 별로 첨가량을 달리한 고추씨 고추장을 제조하여 $28^{\circ}C$에서 100일 동안 숙성시키면서 화학적 특성을 조사하였다. 총 균수는 발효 기간 중 2.7~3.22 log CFU/g 의 수준을 유지하였으며. 처리구간에 차이는 없었고, 산도의 변화는 pH와 반대로 숙성기간 동안 증가하는 경향을 보여 숙성 100일째 고추씨분말 첨가 고추장의 산도는 0.45~0.42 mg% 수준이었다. DPPH 라디칼 소거 활성은 제조 초기보다 고추씨첨가량이 많을수록 숙성 될수록 증가하였다. 기호성 등의 관능검사에서 고추씨가루(20% 첨가)에서 가장 발효에 적합한 조건으로 판단된다.

• Journal of Microbiology and Biotechnology
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• 제20권7호
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• pp.1128-1133
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• 2010

The diversity and abundance of ammonia-oxidizing bacteria (AOB) in activated sludge were compared using PCR-DGGE and real-time PCR assays. Activated sludge samples were collected from five different types of wastewater treatment plants (WWTPs) mainly treating textile, paper, food, and livestock wastewater or domestic sewage. The composition of total bacteria determined by PCR-DGGE was highly diverse between the samples, whereas the community of AOB was similar across all the investigated activated sludge. Total bacterial numbers and AOB numbers in the aerated mixed liquor were in the range of $1.8{\times}10^{10}$ to $3.8{\times}10^{12}$ and $1.7{\times}10^6$ to $2.7{\times}10^{10}$ copies/l, respectively. Activated sludge from livestock, textile, and sewage treating WWTPs contained relatively high amoA gene copies (more than $10^5$ copies/l), whereas activated sludge from food and paper WWTPs revealed a low number of the amoA gene (less than $10^3$ copies/l). The value of the amoA gene copy effectively showed the difference in composition of bacteria in different activated sludge samples and this was better than the measurement with the AOB 16S rRNA or total 16S rRNA gene. These results suggest that the quantification of the amoA gene can help monitor AOB and ammonia oxidation in WWTPs.

• Asian-Australasian Journal of Animal Sciences
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• 제24권8호
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• pp.1086-1091
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• 2011

This experiment was designed to investigate the effect of lerak extract on the dynamic of rumen microbes in the in vitro fermentation of diet with different ratios of forage and concentrate. In vitro fermentation was conducted according to the method of Tilley and Terry (1963). The design of experiment was a factorial block design with 2 factors. The first factor was the ratio of forage and concentrate (90:10, 80:20, and 70:30 w/w) and the second factor was the level of lerak extract (0, 0.6, and 0.8 mg/ml). Total volatile fatty acid (VFA) concentration, proportional VFA and NH3 concentration were measured at 4 h incubation. Protozoal numbers in the buffered rumen fluid after 4 and 24 h of incubation were counted under a microscope. Bacterial DNAs of buffered rumen fluid were isolated from incubated samples after 24 h of incubation using a QiaAmp kit. Total bacteria, Fibrobacter succinogenes, Ruminococcus albus, and Prevotella ruminicola were quantified using real time polymerase chain reaction (PCR). Lerak extract markedly reduced protozoal numbers in buffered rumen fluid of all diets after 24 h of incubation. Total bacteria did not change with lerak extract addition. While no difference in F. succinogenes was found, there was a slight increase in R. albus number and a significant enhancement in P. ruminicola number by increasing the level of lerak extract in all diets. Propionate concentration significantly increased in the presence of lerak extract at level 0.8 mg/ml. It was concluded that the addition of lerak extract could modify rumen fermentation and had positive effects on rumen microbes.

• 한국식품위생안전성학회지
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• 제12권3호
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• pp.205-209
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• 1997

Alcohol treatment was applied to ginseng powder for the improving hygienic quality of ginseng powder. A bacterial strain designated as GT5 was isolated from ginseng powder contaminated and was identified as Escherichia coli species by IMVIC test method. Ethanol used as alcohol, inhibited strongly the growth of coliforms in ginseng powder at the concentrations of 50 to 90%. Ethanol treatment also decreased numbers of total bacteria at the same concentrations. There was not significant changes in saponin of ginseng powder after treated with ethanol. However, ethanol treatment caused a decrease in Hunter's color L value and an increase in a and b values of ginseng powder. As a hygienic quality control of ginseng powder, ethanol treatment could be cosidered as an effective means for decontaminating microorganisms in ginseng powder.

• 대한지하수환경학회지
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• 제5권4호
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• pp.215-222
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• 1998

지하수 세균 군집에 미치는 환경요인의 영향을 분석하기 위하여, 서울 시내에서 음용수로 사용하는 2개 정점과 음용수외 생활용수로 사용하고 있는 8개 정점을 대상으로 조사하였다. 물리.화학적 환경요인과 중금속의 농도, 및 세균 군집의 분포 등 40개 변수를 분석한 결과, 음용수로 사용하는 정점을 제외한 나머지 정점에서 질산성 질소와 암모니아가 용수목적별 수질기준의 기준치 이상으로 측정되었다. 총세균은 5.1~41.4$\times$$10^{5}$cells/ml 범주로, 종속영양세균과 기능성 세균군집은 0.01~29.6$\times$$10^4$cfu/ml의 범주로 조사되었다. 세포외 효소의 활성도는 0.005~11.3$\mu$M/l/hr 의 범주로 나타났고, lipase, phophatase, $\beta$-glucosidase, cellulase, chitinase, amylase 순으로 활성도가 나타났다. 정점별로 조사된 세균 군집에 미치는 환경요인의 상호관계는 대응분석(correspondence analysis)과 다차원 척도법 분석(multidimensional scaling; MDS)으로 하였으며, 그 결과 4개의 집단으로 구분되었으며, 세균 군집에 미치는 주요한 환경요인은 정점별 잠재오염원과 일치하는 양상을 보였다.다.

• Journal of Animal Science and Technology
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• 제65권2호
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• pp.387-400
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• 2023

Ruminal protozoa, especially entodiniomorphs, engulf other members of the rumen microbiome in large numbers; and they release oligopeptides and amino acids, which can be fermented to ammonia and volatile fatty acids (VFAs) by amino acid-fermenting bacteria (AAFB). Studies using defaunated (protozoa-free) sheep have demonstrated that ruminal protozoa considerably increase intraruminal nitrogen recycling but decrease nitrogen utilization efficiency in ruminants. However, direct interactions between ruminal protozoa and AAFB have not been demonstrated because of their inability to establish axenic cultures of any ruminal protozoan. Thus, this study was performed to evaluate the interaction between Entodinium caudatum, which is the most predominant rumen ciliate species, and an AAFB consortium in terms of feed degradation and ammonia production along with the microbial population shift of select bacterial species (Prevotella ruminicola, Clostridium aminophilum, and Peptostreptococcus anaerobius). From an Ent. caudatum culture that had been maintained by daily feeding and transfers every 3 or 4 days, the bacteria and methanogens loosely associated with Ent. caudatum cells were removed by filtration and washing. An AAFB consortium was established by repeated transfers and enrichment with casamino acids as the sole substrate. The cultures of Ent. caudatum alone (Ec) and AAFB alone (AAFB) and the co-culture of Ent. caudatum and AAFB (Ec + AAFB) were set up in three replicates and incubated at 39℃ for 72 h. The digestibility of dry matter (DM) and fiber (NDF), VFA profiles, ammonia concentrations, pH, and microscopic counts of Ent. caudatum were compared among the three cultures. The co-culture of AAFB and Ent. caudatum enhanced DM degradation, VFA production, and Ent. caudatum cell counts; conversely, it decreased acetate: propionate ratio although the total bacterial abundance was similar between Ec and the Ec + AAFB co-culture after 24 h incubation. The ammonia production and relative abundance of C. aminophilum and P. anaerobius did not differ between AAFB alone and the Ec + AAFB co-culture. Our results indicate that Ent. caudatum and AAFB could have a mutualistic interaction that benefited each other, but their interactions were complex and might not increase ammoniagenesis. Further research should examine how such interactions affect the population dynamics of AAFB.

• Asian-Australasian Journal of Animal Sciences
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• 제13권11호
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• pp.1554-1560
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• 2000

Ninety-six crossbred (Large White${\times}$Landrace${\times}$Duroc) pigs, weaned at 35 days of age, were assigned to four dietary treatments in order to investigate the effects of oral antibiotics on the performance and the intestinal microflora of weanling pigs. Pigs were fed either a basal diet, without antibiotics, or the basal diet plus either 50 ppm acetylspiramycin, 50 ppm olaquindox, or 100 ppm bacitracin zinc. The pigs were housed eight per pen with three pens per treatment in an environmentally controlled nursery. Ten days after weaning, three pigs from each treatment were slaughtered and intestinal pH, microflora, and volatile fatty acid concentration were determined. At the end of the 4 week trial, the remaining pigs were weighed and feed consumption was measured. Average daily gains for pigs fed acetylspiramycin, olaquindox, bacitracin zinc and the control diet were 0.43, 0.40, 0.37, and 0.34 kg per day (p=0.001), respectively. Antibiotic addition did not modify feed intake, but acetylspiramycin improved feed conversion (p=0.003). In comparison with the control, acetylspiramycin significantly increased Bifidobacteria numbers in the jejunum (p=0.082) and ileum (p=0.014) and decreased total bacterial counts throughout the intestine (p<0.01 except for the ileum where p=0.079). Acetate production was significantly lower in the cecum (p=0.028) and colon (p=0.079) of pigs fed acetylspiramycin. In addition to increasing numbers of Bifidobacteria in the jejunum (p=0.082) and ileum (p=0.014), olaquindox increased Lactobacillus in the jejunum (p=0.004) and decreased E. coli in the colon (p=0.022). Bacitracin zinc increased Lactobacillus numbers in the jejunum (p=0.004) and Bifidobacterium concentrations in the jejunum (p=0.082) and ileum (p=0.014).

• 한국식품저장유통학회지
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• 제18권1호
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• pp.7-12
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• 2011

파프리카(Capsicum annuum var. angulosum)는 우리나라의 대표적인 수출농산물로서 지속적인 수출확대를 위해서는 안전성 확보가 중요하다. 지금까지 수출과채류의 생물학적 위해요소에 대한 연구는 많이 이루어 지지 않았다. 본 연구는 우리나라의 대표적인 수출 농산물인 파프리카를 대상으로 미생물오염실태를 모니터링하고, 보관온도에 따른 세균오염도 변화를 분석하였다. 파프리카의 평균 총호 기성균 수는 $2.3{\pm}0.3$ log CFU/g이었으며, 대장균군은 발견되지 않았다. 파프리카에서는 황색포도상구균이 발견되지 않았으며, 또한 Salmonella spp., Listeria spp. 및 E. coli O157:H7도 검출되지 않았다. 파프리카를 상온 및 $4^{\circ}C$에 각각 보관후 20일동안 세균 오염도를 측정한 결과, 상온에 보관시 총호기성균 수는 구입 14~16일에 가장 많이 증가하 였으나(4배 이상), $4^{\circ}C$에 보관시에는 세균 수 증가가 완만하였다. 대장균군은 상온에서 2회 검출되었으나, $4^{\circ}C$에서는 검출되지 않았다. 이상의 결과로 보아, 수출용 파프리카는 생물학적으로 안전하였으나, 상온에 장기간 보관시 유해미생물의 오염 가능성이 있으므로 유통과정중 철저한 위생관리가 요구된다.

• 상하수도학회지
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• 제26권3호
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• pp.399-408
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• 2012

The overall goal of this study was to characterize and quantify ammonia-oxidizing bacteria (AOB) in four different full-scale sequence batch reactor (SBR) wastewater treatment plants. Also, this study focused on assessing the occurrence of the alternative ammonia-oxidizing microbes such as anammox (anaerobic ammonia oxidation) bacteria (AMX) and ammonia-oxidizing archaea (AOA) in these systems. Based on total AOB numbers and the estimated cell density in the mixed liquor samples, AOB constituted 0.3 - 1.8% of the total bacterial population in the four WWTPs. Based on clone library, Nitrosomonas ureae-like AOB were dominant in plant A and B, while plant C and D had Nitrosomonas nitrosa-like AOB as major AOB group. The four different AMX primer sets targeting AMX 16S rRNA gene produced PCR amplicons distantly related to Chlamydia and Planctomycetales group bacteria. However, it was not clear these groups of bacteria perform anammox reaction in the SBR plants. Also, molecular evidence of AOA was found in one of the SBR plants, with a sequence located in the deep branch of the sediment creanarchaeota group.

• 미생물학회지
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• 제38권1호
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• pp.31-37
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• 2002

경북 경산시 에 위치한 남매지 에서 세균군집 의 구조를 fluorescent in situ hybridization(FISH) 방법을 이용하여 분석하였고 아울러 세균군집크기에 영향을 주는 환경요인을 측정하여 그 상관성을 파악하고자 하였다. 담수계에 우점하는 것으로 알려진 proteobacteria($\alpha$.$\beta$.$\gamma$-subclasses)와 글Cytophaga-Flavobacterium (CF) group에 속하는 진정세균군의 연중변화를 정점별로 측정하였다. 총세균수에 대한 각 세균군집 비율은 정점간의 큰 차이 없이 $\alpha$-subclass가 4.0~29.2%,$\beta$-subclass가 1.7~25.8%, $\gamma$-subclass가 1.8~12.8%를, 그리고 CF group은 4.9~36.3%의 군집 비율을 나타냈다. 온도,SS, pH, DOC,질산염, 조류 현존량 등 환경요인과 세균군집 간의 상관관계를 분석한 결과, 총세균수는 수온, DOC,55, eubacteria는 DOC, 녹조류 현존량, $\gamma$-subclass 세균군은 DOC, CF group세 균은 녹조류 현존량과 양의 상관성을 나타낸 반면 $\beta$-subclass는 남세균 . 총 조류 현존량과 음의 상관성을 나타냈다.