• Journal of Microbiology
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• 제45권6호
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• pp.479-484
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• 2007

Bacterial communities at 10 cm, 100 cm, and 200 cm depths in a 100-year-old lead-zinc tailing heap were evaluated by constructing 16S rRNA gene libraries. In total, 98 operational taxonomic units (OTUs) were identified from 193 clones at a 3% sequence difference level. The OTU number and species richness decreased with the depth. Species composition was significantly different between the three libraries. Fifty-seven percent of the examined clones were Acidobacteria and 27% belonged to Proteobacteria. Other sequences included Chloroflexi, Firmicutes, Chlamydiae, Actinobacteria, Gemmatimonadetes, Nitrospira, and three unclassified OTUs. Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Firmicutes, and Actinobacteria were mainly distributed in the rhizosphere of naturally colonizing plants; however, Deltaproteobacteria, Acidobacteria, and Chloroflexi tended to inhabit the deeper tailings (below the 100 cm-depth).

• 한국동물위생학회지
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• 제24권1호
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• pp.89-94
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• 2001

In order to investigate the relationship between milk hygienic quality and some environmental factors such as the herd size and types of milking machines, we sampled and examined the level of total bacterial count, coliforms, Staphyococcus aureus, somatic cell counts(SCC) and fat rates in raw milk. of the 84 dairy farms, the prevalence of level on number of standard plate count over 100,000cfu/$m\ell$ and coliforms over 1,000cfu/$m\ell$ in bulk milk were 25.0% and 15.6%, respectively. Also, 2 farms(2.4%) were exceed the level on number of 500cfu/$m\ell$ S aureus in raw milk. The prevalence of dairy herd with first grade of total bacterial count(TBC) according to bucket, pipe line and parlour milking system was 40.0%, 74.0% and 84.0%, respectively. The prevalence of dairy herd with first grade of TBC according to grade 1, 2 and 3 by SCC was 77.8%, 83.2%. and 69.2%, respectively. Therefore, the relationships between hygienic quality in raw milk and the herd size, types of milking machines, were significant. In conclusion, this study could be overemphasized the importance of herd management condition for milk hygienic qualify.

• 한국어병학회지
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• 제11권1호
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• pp.23-27
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• 1998

1991년 1월부터 1997년 12월까지 제주도 넙치양식장의 감염어에서 발생한 세균성질병의 연도별 발생상황은 단독 감염질병에 있어서는 1997년에 243건(26.8%)으로 가장 높았고, 1993 년에 82건(9.1%)으로 가장 낮았다. 혼합 감염질병에 있어서는 1997년에 94건(28.1%)으로 가장 높았으며 1991년에 18건(5.4%)으로 가장 낮았다. 단독감염의 월별발생상황은 8월에 132건 (14.6%)으로 가장 높았고, 1월에 38건(4.2%)으로 가장 낮았다. 혼합감염의 월별발생상황은 월별차이는 별로 없었으나 11월과 12월에 각각 9건으로 가장 낮았다. 단독 감염의 세균 종류별 연도별 발생 상황은 비브리오증이 437건(48.2%)으로 가장 높았으며 활주세균증이 22건(2.4%)으로 가장 낮았다. 혼합 감염의 연도별 빌생 상황은 비브리오+활주세균증이 178건(53.1%)으로 가장 높았으며 에드와드+연쇄구균증이 28건(8.4%)으로 가장 낮았다.

• 한국식품위생안전성학회지
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• 제38권1호
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• pp.19-25
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• 2023

비가열 닭고기 분쇄육의 제조 시 향신료의 첨가에 의한 세균의 증식 억제 효과에 대하여 연구하였다. 닭가슴살 분쇄육의 일반성분은 수분 72.98±0.15%, 조단백질 23.37±0.46%, 조지방 1.00±0.03%, 조회분 1.90±0.03%였다. 향신료 첨가에 의한 미생물 증식 억제 효과는 로즈마리 > 마늘 > 겨자 순이었으며, 첨가량이 증가할수록 억제 효과가 커졌다. 닭고기 분쇄육의 일반세균 및 대장균 증식 억제를 나타내는 향신료의 최적 첨가 농도는 로즈마리 2%, 마늘 4%, 겨자 1.2%였다. 일반세균 및 대장균에 대한 증식 억제 효과는 단독 및 혼합 첨가 시 저장기간 동안 기간별로 차이가 있었고, 저장 9일째 억제 효과는 MixA(97.4%) > 로즈마리(96.9%) > MixB(96.3%) > 마늘(53.7%) > 겨자(33.3%) 순이었다. 닭고기 분쇄육에 살균마늘과 비살균마늘을 첨가하여 비교했을 때 일반세균 수는 살균마늘 처리구가 비살균마늘 처리구에 비해 초기 2.6-3.0 log CFU/g, 9일째 2.4-3.2 log CFU/g 정도 낮았고, 저장기간이 경과할수록 그 수가 감소하였다. 비살균마늘 처리구는 대조구보다 높은 일반세균 수를 나타냈으며, 저장기간이 경과할수록 증가하는 경향을 나타냈다. 대장균 수의 경우 살균마늘 처리구가 비살균마늘 처리구에 비해 저장 0일째 0.4-1.0 log CFU/g, 9일째 0.5-1.5 log CFU/g 정도 낮았으며, 저장기간의 경과에 따른 변화는 일반세균 수와 비슷한 경향을 나타냈다. 결론적으로 로즈마리, 마늘, 겨자의 다양한 혼합적용에 의해 닭고기 분쇄육 제품의 미생물적 안전성이 향상되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제27권8호
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• pp.1131-1140
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• 2014

This research focused on the effects of different doses of Bacillus subtilis KN-42 on the growth performance, diarrhea incidence, faecal bacterial flora, and the relative number of Lactobacillus and Escherichia coli in faeces of weaned piglets to determine whether the strain can serve as a candidate antimicrobial growth promoter. A total of 360 piglets (initial body weight $7.14{\pm}0.63$ kg) weaned at $26{\pm}2$ days of age were randomly allotted to 5 treatment groups (4 pens per treatment with 18 pigs per pen) for a 28-day trial. Dietary treatments were basal diet without any antimicrobial (negative control; NC), basal diet supplemented with 120 mg/kg feed of neomycin sulfate (positive control; PC) and basal diet supplemented with $2{\times}10^9$ (L), $4{\times}10^9$ (M) and $20{\times}10^9$ (H) CFU/kg feed of B. subtilis KN-42. During the overall period, average daily gain and feed efficiency of piglets were higher in groups PC, M, and H than those in group NC (p<0.05), and all probiotics and antibiotics groups had a lower diarrhea index than group NC (p<0.05). The 16S rDNA gene-based methods were used to analyze faecal bacterial flora on day 28 of experiment. The result of denaturing gradient gel electrophoresis analysis showed that supplementation of B. subtilis KN-42 to the diet changed the bacterial communities, with a higher bacterial diversity and band number in group M than in the other four groups. Real-time polymerase chain reaction analysis showed that the relative number of Lactobacillus were higher in groups PC and H than in group NC (p<0.05), and the supplemented B. subtilis KN-42 to the diet also reduced the relative number of E. coli (p<0.05). These results suggest that dietary addition of B. subtilis KN-42 can improve the growth performance and gastrointestinal health of piglets.

• 생명과학회지
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• 제22권11호
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• pp.1463-1469
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• 2012

전통발효식품인 고추장의 기능성을 부가하고 맛과 기호성을 개선하기 위하여 토마토 퓨레조청을 첨가한 고추장을 최적발효조건을 설정하기 위해 소금의 농도를 달리하여 GCJ 14, 16, 18, 20의 조건으로 제조한 후 발효하여 고추장의 이화학적 성분의 변화로 발효의 최적조건을 설정하였으며, 기능성 성분인 라이코펜의 함량을 분석하였다. 그 결과 토마토 퓨레 조청 함유 고추장의 pH의 변화는 발효기간동안 감소하였으며, 당도는 감소하였다 증가를 반복하였으며, 수분과 염도, 색도는 유의적인 변화를 나타내지 않았다. 미생물의 변화는 발효가 진행됨에 따라 총균수와 유산균수는 증대되었으며, 총균수 대비 유산균의 생성비율은 GCJ 18와 GCJ 20조건에서 높은 비율을 확인하였다. 토마토 기능성 성분인 라이코펜의 함량의 변화는 발효과정 동안 유의적 변화를 나타내지 않았다. 그리고 제조된 고추장의 조단백질, 조지방, 조회분, 탄수화물의 일반성분함량의 변화와 맛, 기호성 등의 관능검사에서 GCJ 20에서 가장 발효에 적합한 조건으로 판단된다. 따라서 토마토 퓨레조청 함유 고추장으로 현대인의 기호에 맞으면서 기능성이 부과된 고추장의 개발의 가능하다고 사료된다.

• 미생물학회지
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• 제36권2호
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• pp.125-129
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• 2000

낙동강 연안 수역에서 세균의 생산성과 생산물량을 측정하여 미생물의 먹이고리에 기여하는 정도를 파악하기 위해 미생물학적 요인과 주요 환경요인을 측정하였다. 낙동강 연안 수계는 겨울철 갈수기에 유입되는 부영양화 담수의 영향을 많이 받았다. 종속영양세균과 총세균의 개체수는 각각$5.4{\times}10^2 ~ 3.2{\times}10^4, 2.2{\times}10^5 ~ 9.8{\times}10^5 $cells/ml이었으며, 세균의 평균 체적과 생물량은 각각 0.023~0.201$\mu$$m^3$/cell, 0.010~0.140$\mu$g-C/ml로 정점별, 계절별 차이는 크지 않았으나 체적과 총세균수가 반비례하였다. Thymidine pool size는 12.93~44.66nM로, 동계에 비해 하계에 세균이 이용하기 쉬운 pool로 이루어져 하계의세균 이차 생산성 측정치가 과소 평가될수 있음을 보여주고 있다. 종속영양세균의 이차생산성은 0.12~22.38$\mu$g-C/l/h의 변화 범위를 나타내었으며, 담수 유출부와 인접한 정점에서 가장 낮은 값을 보였다. 동계에 세균 생산성의 분포는 엽록소 a 및 수온 변화와 밀접한 상관성을 보였으며, 또한 세균 생산량도 많은 영향을 미치는 것으로 나타나 본 조사 수역에서 측정된 세균 생산성의 상당 부분은 식물플랑크톤의 공합성 산물을 이용하는 세균 생물량의 증가임을 알 수 있다.

• The Plant Pathology Journal
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• 제23권3호
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• pp.203-209
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• 2007

Infection structures were observed using a fluorescence microscope at the penetration sites on the leaves of potato plants pre-inoculated with the bacterial strains Pseudomonas putida TRL2-3, Micrococcus luteus TRK2-2, and Flexibacteraceae bacterium MRL412, which mediated an induced systemic resistance on potato plants against late blight disease caused by Phytophthora infestans. In order to compare the infection structures on the leaves expressing systemic acquired resistance, the leaves of potato plants pre-treated with DL-3-amino butyric acid (BABA) were also observed after challenge inoculation with the same pathogen. The infection structures were investigated. The total number of germination and appressorium formation of P. infestans were counted. Furthermore, the frequencies of fluorescent epidermal cells at the penetration sites, which indicate a defense response of plant cell, were estimated. There were no differences on the germination rates of the fungal cysts among the untreated control, BABA pre-treated, and bacterial strains pre-inoculated plants. However, appressorium formation was slightly decreased on the leaves of BABA pre-treated plants compared to those of untreated as well as bacterial strains pre-inoculated plants. Furthermore, the frequencies of fluorescent cells of BABA pre-treated and bacterial strains pre-inoculated were higher than that of untreated plants, indicating an active defense reaction of the host cells against the fungal attack. On the other hand, the pre-treatment with BABA caused a stronger fluorescent of epidermal cells at the penetration sites compared to the pre-inoculation with the bacterial strains. Interestingly, the frequency of fluorescent cells by BABA, however, was lower than that by the bacterial strains. Based on the results it is suggested that the infection structures showing resistance reaction on the leaves of potato plants were different between by pre-inoculation with bacterial strains and by pre-treatment with BABA against the late blight pathogen.

• 한국연초학회지
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• 제15권1호
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• pp.34-48
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• 1993

This experiment were conducted to investigate heterosis and combining ability for several mutant characters by analyzing dialled crosses of flue-cured tobacco. In a dialled cross of 3 flue-cured varieties and the mutant line 83H -5, the heterosis was somewhat higher in Fl than in F2. For growth character, the heterosis was 0.28-6.03% in plant height, leaf number, leaf shape index and yield, and was 43.2% for bacterial wilt disease index. The mutant line 83H-5 showed significantly negative GCA effect for plant height, leaf width and bacterial wilt disease index in Fl and F2, leaf length in F2, and positive GCA effect for total alkaloids, total nitrogen in Fl and days to flower in F2, respectively. Specific combining ability(SCA) in 83H-5 x Hicks was significant in negative effect for leaf length(F2), number of leaves(F2), leaf shape(F1, F2), bacterial wilt(F2) and alkaloids(F1), and in 83H-5 x NC 2326 in positive effect for leaf length(F1, F2) and leaf width(F2), and for 83H-5 x NC 82 in positive effect for plant height(F1, F2) and leaf width(F2), and for 83H-5 x NC 82 in Positive effect for Plant height(F1, F2), leaf length(F2) and yield(F1, F2).

• Asian-Australasian Journal of Animal Sciences
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• 제13권12호
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• pp.1708-1716
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• 2000

A study was made of diurnal changes in the ruminal bacteria associated with feed particles, i.e., non-associated (NAB), loosely associated (LAB), and tightly associated with particles (TAB), and the TAB concentration in different particle sizes from sheep fed orchardgrass (OG) or alfalfa (ALF) hay. Diaminopimelic acid (DAPA) was used to determine the TAB mass. Results showed that the bacterial masses in NAB and LAB were small, but comprised over 90% in TAB. The TAB mass in the ALF group sharply increased within 2 h after feeding and decreased afterward. The TAB mass showed the same trend in the OG group, increasing from 0 h to 2 h, but remained at the same level up to 14 h after feeding. The peak bacterial mass was, however, lower in the OG than the ALF group. The TAB concentration reflected the changes in total particulate tightly associated bacterial masses in both groups of hay fed sheep. Number of bacterial colonies per particle increased as the particulate size decreased in both groups. This difference, however, tended to decline as the postprandial period was prolonged. DAPA, however, tended to overestimate the TAB mass in the reticulo-rumen digesta of the hay fed sheep.