• Clinical and Experimental Pediatrics
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• 제56권9호
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• pp.369-376
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• 2013

A complex interplay between genetic and environmental factors partially contributes to the development of allergic diseases by affecting development during prenatal and early life. To explain the dramatic increase in the prevalence of allergic diseases, the hygiene hypothesis proposed that early exposure to infection prevented allergic diseases. The hygiene hypothesis has changed to the microbial hypothesis, in which exposure to microbes is closely linked to the development of the early immune system and allergic diseases. The intestinal flora may contribute to allergic disease through its substantial effect on mucosal immunity. Based on findings that exposure to microbial flora early in life can change the Th1/Th2 balance, thus favoring a Th1 cell response, probiotics may be beneficial in preventing allergic diseases. However, evidence from clinical and basic research to prove the efficacy of probiotics in preventing allergy is lacking. To date, studies have yielded inconsistent findings on the usefulness of probiotics in allergic diseases. It is difficult to demonstrate an exact effect of probiotics on asthma, allergic rhinitis, and food allergy because of study limitations, such as different first supplementation period, duration, different strains, short follow-up period, and host factors. However, many studies have demonstrated a significant clinical improvement in atopic dermatitis with the use of probiotics. An accurate understanding of the development of human immunity, intestinal barrier function, intestinal microbiota, and systemic immunity is required to comprehend the effects of probiotics on allergic diseases.

• 한국초지조사료학회지
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• 제35권4호
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• pp.321-326
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• 2015

본 시험은 동계작물인 쌀보리의 알곡에 대한 사료로서의 활용도를 제고하고자 미생물 분포를 분석하고, 발효과정중 이화학적 및 미생물학적 특성의 변화 분석을 통하여 효과적인 발효사료 제조방법을 제시하고자 수행하였다. 즉, 수확된 쌀보리 종실에 시판 생균제를 기준에 맞게 접종한 후 공기와 접촉하지 않도록 밀봉하여 $37^{\circ}C$에서 7일간 발효를 통해 쌀보리 종실의 저장성과 안전성을 증진시킬 수 있다. 쌀보리 종실 자체에 Staphylococcus속과 Bacillus속의 미생물들이 다수 존재하여 자연발효의 가능성이 있음을 보여 주었다. 또한 생균제를 접종하지 않은 쌀보리 종실도 기간이 경과됨에 따라 산도가 저하되고 유산균 수가 증가하여 발효가 이루어지고 있는 것으로 나타났다. 그러나 쌀보리 종실에 생균제를 접종하였을 경우, 발효 7일차에 pH가 $4.33{\pm}0.02$로 발효가 더 빨리 진행되었으며, 유산균의 수도 전체 발효기간 동안 미 접종 대조구에 비해 높게 유지되었으나, 효모의 수에 있어서는 차이가 나타나지 않았다. 발효에 의해 쌀보리 종실의 산도가 저하됨에 따라 초기 $10^7cfu/g$ 이상 검출되었던 대장균이 발효 7일차 이후부터는 전혀 검출되지 않아 발효가 쌀보리 종실의 안전성을 유지시키는 데 있어 효과적인 저장방법으로 나타났다.

• Advances in environmental research
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• 제2권1호
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• pp.61-80
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• 2013

Quantification of viable forms of microbial community (bacteria and fungi) using culture-dependent methods was done in order to characterize the indoor air quality (IAQ). Role of those factors, which may influence the concentration of viable counts of bacteria and fungi, like ventilation, occupancy, outdoor concentration and environmental parameters (temperature and relative humidity) were also determined. Volumetric-infiltration sampling technique was employed to collect air samples both inside and outside the schools. As regard of measurements of airborne viable culturable microflora of schools during one academic year, the level of TVMCs in school buildings was ranged between 803-5368 cfu/$m^3$. Viable counts of bacteria (VBCs) were constituted 63.7% of the mean total viable microbial counts where as viable counts of fungi (VFCs) formed 36.3% of the total. Mean a total viable microbial count (TVMCs) in three schools was 2491 cfu/$m^3$. Outdoor level of TVMCs was varied from 736-5855 cfu/$m^3$. Maximum and minimum VBCs were 3678-286 cfu/m3 respectively. Culturable fungal counts were ranged from 268-2089 cfu/$m^3$ in three schools. Significant positive correlation (p < 0.01) was indicated that indoor concentration of viable community reliant upon outdoor concentration. Temperature seemed to have a large effect (p < 0.05, p < 0.01) on the concentration of viable culturable microbial community rather than relative humidity. Consistent with the analysis and findings, the concentration of viable cultural counts of bacteria and fungi found indoors, were of several orders of magnitude, depending upon the potential of local, spatial and temporal factors, IO ratio appeared as a crucial indicator to identify the source of microbial contaminants.

• 농업과학연구
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• 제40권2호
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• pp.131-137
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• 2013

The inhibitory effect of citrus peel extract, onion peel extract, calcium lactate and phosvitin on microbial growth was investigated in seasoned chicken breast meat during aerobic storage at $4^{\circ}C$, $10^{\circ}C$ and $20^{\circ}C$. Citrus peel and onion peel extract significantly improved (p<0.05) the microbial quality of the sample by reducing the initial counts of the microbial flora compared to control and other two treatments. Data clearly revealed that the counts of the total aerobic bacteria significantly increased with the increase in storage temperature. The shelf life of all samples stored under $20^{\circ}C$ was less than 6 days, while the shelf life of citrus and onion treatment can be extended more than 9 days at $4^{\circ}C$ and more than 6 days at $10^{\circ}C$ in aerobic storage condition. These results indicated that citrus and onion peel extracts are efficient treatment methods to prevent microbial spoilage of seasoned chicken products during storage at $4^{\circ}C$. However, there was an adverse effect of addition of citrus and onion peel extract on several sensory attributes which need to be improved by reformulation of seasoning.

• 한국토양비료학회지
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• 제32권1호
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• pp.76-83
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• 1999

가축분 퇴비가 토양의 미생물상에 미치는 영향을 조사하고자 농업과학기술원 시험포장에 시용량($8Mg\;ha^{-1}$, CM-8구: $29Mg\;ha^{-1}$, CM-29구: $57Mg\;ha^{-1}$, CM-57구)을 달리하여 돈분퇴비를 시비하고 봄배추를 재배하면서 생육시기별로 토양을 채취하여 미생물상을 조사한 결과를 요약하면 다음과 같다. 미생물의 생균수는 무비구(대조구)에 비하여 화학비료구(NPK구)에서 세균, 방선균, 사상균수는 높았으나 세균 중에서 Bacillus속과 형광성 Pseudomonas속 균수는 현저히 낮았다. 반면에 퇴비 구에서는 Bacillus속을 제외한 모든 미생물이 시용량에 비례하여 증가하였고, 퇴비 $57Mg\;ha^{-1}$ 시용구(CM-57)에서는 세균 사상균, 방선균, 형광성 Pseudomonas속 균수가 대조구에 비하여 각각 3.4, 2.3, 3.2, 3.1배 높았다. 퇴비구에 있어서 세균(Bacillus속 포함)의 경우 배추의 생육초기에 정점에 도달하였으나, 형광성 Pseudomonas속은 생육후기에 사상균과 방선균은 수확기에 최고의 밀도를 보였다. 한편 토양미생물의 근권효과는 형광성 Pseudomonas속이 가장 컸다. 재배토양의 화학성분은 pH를 제외한 모든 항복에서 퇴비시용량에 비례하여 증가하는 경향이었으며, NPK구의 경우 EC와 K함량은 $0.89dS\;m^{-1}$ 및 $1.64cmol^+kg^{-1}$로 각각 대조구에 비하여 3.4 및 5.0배로서 모든 처리구 가운데 가장 높았다. 배추의 수량은 대조구가 $44Mg\;ha^{-1}$이었으나 퇴비구에서는 시용량에 비례하여 증수되어 CM-57구에서 $163Mg\;ha^{-1}$으로 처리구 중 가장 많은 수량을 거두었고 NPK구에서는 이보다 적은 $143Mg\;ha^{-1}$이었다.

• 한국토양비료학회지
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• 제47권6호
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• pp.451-456
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• 2014

Organic amendment practices can influence diversity and activities of soil microorganisms. There is a need to investigate this impact compared with other types of materials. This study was carried out to evaluate the long term effects of chemical and organic fertilizer on soil microbial community in upland field. During the last 11 years green manure, rice straw compost, rapeseed cake, pig mature compost, NPK, and NPK + pig mature compost were treated in upland soil. Organic fertilizer treatment found with high bacterial colony forming units (CFUs) as compared to chemical and without fertilizer treatment. There was no significant difference in the actinomycetes and fungal population. The average well color development (AWCD) value was the highest in green manure and, the lowest in without fertilizer treatment. Analyses based on the denaturing gradient gel electrophoresis (DGGE) profile showed that rice straw compost and pig mature compost had a similar banding pattern while rapeseed cake, NPK, NPK + pig mature compost and without fertilizer treatment were clustered in another cluster and clearly distinguished from green manure treatment. Bacterial diversity can be highly increased by the application of organic fertilizer while chemical fertilizer had less impact. It can be concluded that green manure had a beneficial impact on soil microbial flora, while, the use of chemical fertilizer could affect the soil bacterial communities adversely.

• Journal of Microbiology and Biotechnology
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• 제30권11호
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• pp.1640-1650
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• 2020

Colorectal cancer (CRC) is the leading cause of common malignant neoplasm worldwide. Many studies have analyzed compositions of gut microbiota associated with various diseases such as inflammatory bowel diseases (IBD) and colon cancer. One of the most representative bacteria involved in CRC is enterotoxigenic Bacteroides fragilis (ETBF), a species belonging to phylum Bacteroidetes. We used ETBF colonized mice with azoxymethane (AOM)/dextran sulphate sodium (DSS) and zerumbone, a compound with anti-bacterial effect, to determine whether zerumbone could restore intestinal microbiota composition. Four experimental groups of mice were used: sham, ETBF colonized AOM/DSS group, ETBF colonized AOM/DSS group zerumbone 60 mg kg-1 (ETBF/AOM/DSS + Z (60)), and only zerumbone (60 mg kg^-1)-treated group. We performed reversible dye terminators-based analysis of 16S rRNA gene region V3-V4 for group comparison. Microbiota compositions of ETBF/AOM/DSS + Z (60) group and ETBF colonized AOM/DSS group not given zerumbone were significantly different. There were more Bacteroides in ETBF/AOM/DSS + Z (60) group than those in ETBF colonized AOM/DSS group, suggesting that B. fragilis could be a normal flora activated by zerumbone. In addition, based on linear discriminant analysis of effect size (LEfSe) analysis, microbial diversity decreased significantly in the ETBF colonized AOM/DSS group. However, after given zerumbone, the taxonomic relative abundance was increased. These findings suggest that zerumbone not only influenced the microbial diversity and richness, but also could be helpful for enhancing the balance of gut microbial composition. In this work, we demonstrate that zerumbone could restore the composition of intestinal microbiota.

• Asian-Australasian Journal of Animal Sciences
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• 제17권3호
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• pp.401-409
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• 2004

Two experiments were conducted to evaluate the effects of a complex Lactobacilli preparation on performance, resistance to E. coli infection and gut microbial flora of weaning pigs. In exp. 1, twelve pigs (7.65$\pm$1.10 kg BW), weaned at 28 d, were randomly allotted into 2 groups and placed in individual metabolic cages. During the first 7 d, one group of pigs was provided ad libitum access to water containing $10^5$ colony forming units (CFU) Lactobacilli per ml and the control group was provided tap water. The Lactobacilli preparation included Lactobacillus gasseri, L. reuteri, L. acidophilus and L. fermentum, which were isolated from the gastrointestinal (GI) tract mucosa of weaning pigs. On d 8, 20 ml of $10^8$ CFU/ml E. coli solution (serovars K99, K88 and 987P at the ratio of 1:1:1) was orally administered to each pig. Diarrhea scores and diarrhea incidence were recorded from d 7 to 14. On d 14, pigs were euthanized and digesta and mucosa from the stomach, duodenum, jejunum, ileum, cecum and colon were sampled using aseptic technique to determine microflora by culturing bacteria in selective medium. The results showed that Lactobacilli treatment significantly decreased E. coli and aerobe counts (p<0.01) but increased Lactobacilli and anaerobe counts (p<0.01) in digesta and mucosa of most sections of the GI tract. A 66 and 69.1% decrease in diarrhea index and diarrhea incidence, respectively, was observed in the Lactobacilli treated group. In exp. 2, Thirty-six crossbred Duroc$\times$Landrace$\times$Yorkshire piglets, weaned at 28$\pm$2 days, were selected and randomly allocated into 2 groups. There were 18 piglets in each group, 3 piglets in one pen and 6 replicates in each treatment with 3 pens of barrow and 3 pens of female piglet in each treatment. Piglets had ad libitum access to feed and water. The initial body weight of piglet was 7.65$\pm$1.09 kg. Dietary treatments included a non-medicated basal diet with Lactobacilli ($10^5$ CFU/g diet) or carbadox (60 mg/kg) as control. On d 21, six pigs per group (one pig per pen) were euthanized. Ileal digesta was collected to determine apparent amino acid digestibility. Microflora content was determined similarly to exp.1. The results showed that Lactobacilli treatment significantly improved average daily feed intake (ADFI) of pigs compared to carbadox (p<0.05) during the first 2 wks after weaning and average daily gain (ADG) and ADFI increased significantly (p<0.05) from d 8 to 14. Nitrogen and total phosphorus digestibility also increased (p<0.05). Bacterial counts were similar to exp. 1. The results indicate that the complex Lactobacilli preparation improved performance for 2 wks after weaning, enhanced resistance to E. coli infection, and improved microbial balance in the GI tract.

• 한국미생물·생명공학회지
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• 제40권2호
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• pp.111-116
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• 2012

구기자-맥문동 막걸리의 미생물 분포와 최적 저장 기간을 확립하기 위하여 먼저 구기자-맥문동 막걸리를 제조한 후 $4^{\circ}C$와 $20^{\circ}C$에 저장하면서 효모, 총 세균 그리고 젖산균의 생균 수 변화를 조사하였다. 발효가 완료되어 $4^{\circ}C$에서 15일간 저장하는 동안 효모 수는 큰 변화가 없었다. 하지만 30일간 저장한 후에는 약 62%가 감소되었다. $20^{\circ}C$에서 수행한 저장 실험에서는 15일간 저장한 후 초기 효모균수의 87%가 감소하였으며 30일간 저장한 후에는 약 95.2%가 감소되었다. 구기자-맥문동 막걸리의 DGGE 분석에 의해 S. cerevisiae와 미동정의 Saccharomyces sp.가 동정되었는데 $20^{\circ}C$에서 저장하였을 때Saccharomyces sp.가 더 빨리 사멸하였다. 저장 기간 중 총 세균 수와 젖산균의 변화 양상은 유사하였다. $4^{\circ}C$에서 저장 하였을 때 저장 15일 시점에서 총 세균 수는 약 64%가 감소하였으나 그 이후 저장 30일까지 총 세균수의 변화는 크게 없었다. $20^{\circ}C$에서 저장하였을 경우에는 초기 세균 수가 저장 15일 시점에서 총 세균수의 약 95%가 감소하였으며 그 이후 저장 30일 시점까지 총 세균수는 크게 변화하지 않았다. DGGE분석을 통해 발효 개시 시점에서는 W. cibaria가 우점균이었다가 점차 L. fermentum과 P. acidilactici가 증가하여 저장 기간 동안 이들이 우점균으로 존재 함을 확인하였다.

• 한국토양비료학회지
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• 제31권2호
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• pp.204-210
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• 1998

본 시험은 재배이역(栽培履歷)이 서로 상이한 시설재배지에서의 염류집원적지(鹽類集源積地)와 건전지(健全地)의 미생물상(微生物相)의 생태(生態)를 비교해석(比較解析)하고, 미생물(微生物)적 진단(診斷)에 의한 근권환경(根圈環境)의 동태(動態)와 개량기술(改良技術)을 위한 기초자료를 얻고자 수행하였다. 주요 미생물(微生物)의 분포(分布)는 건전지(健全地)에서 형광성(螢光性) Pseudomonas 속 세균(細菌)의 밀도가 높은반면 염류장해지(鹽類障害地)에서는 병원성(病原性) Fuasarium 속의 밀도가 높고 형광성(螢光性) Pseudomonas 속 세균(細菌)이 낮은 분포밀도(分布密度)를 보였다. 토양중 유기물 함량이 증가할수록 Bacillus 속(屬), 형광성(螢光性) Pseudomonas 속(屬), Enterobacteriaceae 등 세균류(細菌類)의 밀도와 Microbial biomass C함량이 크게 증가하였으며, 토양의 전기전도도(電氣傳導度)(EC)가 $5.1dS\;m^{-1}$ 이상으로 높아지면 미생물(微生物)간의 비율중 세균(細菌)/사상균(絲狀菌)(B/F), 방선균(放線菌)/사상균(絲狀菌)(A/F)의 비율이 현저히 낮아지고 형광성(螢光性) Pseudomonas 속(屬) 세균(細菌)이 급격히 감소하였다. 토양 pH와 세균(細菌)과의 관계는 고도의 정(正)의 상관관계(相關關係)를, 사상균(絲狀菌)과는 부(負)의 상관관계(相關關係)를 보였으며, 토양유기물과 방선균(放線菌), Bacillus 속(屬), Enterobacteriaceae와는 각각 $r=0.226^*$, $r=0.334^{**}$, $r=0.276^{**}$, 치환성 Ca및 치환성 Mg함량과 방선균수(放線菌數)와는 각각 $r=0.334^{**}$, $r=0.352^{**}$, 유기물함량과 Microbial biomass C 함량과는 $R=0.439^{**}$의 유의성(有意性) 있는 상관을 보였다.