This study was performed to investigate the effect of heat-stressed environment on rumen microbial diversity in Holstein cows. Rectal temperature and respiration rate were measured and rumen fluid was collected under normal environment (NE; Temperature humidity index (THI)=64.6) and heat-stressed environment (HE; THI=87.2) from 10 Holstein cows (60±17.7 months, 717±64.4 kg) fed on the basis of dairy feeding management in National Institute of Animal Science. The rumen bacteria diversity was analyzed by using the Illumina HiSeq™ 4000 platform. The rectal temperature and respiratory rate were increased by 1.5ﾟC and 53 breaths/min in HE compared to that in NE, respectively. In this study, HE exposure induced significant changes of ruminal microbe. At phylum level, Fibrobacteres were increased in HE. At genus level, Ruminococcaceae bacterium P7 and YAD3003, Butyrivibrio sp. AE2032, Erysipelotrichaceae bacterium NK3D112, Bifidobacterium pseudolongum, Lachnospiraceae bacterium FE2018, XBB2008, and AC2029, Eubacterium celulosolvens, Clostridium hathewayi, and Butyrivibrio hungatei were decreased in HE, while Choristoneura murinana nucleopolyhedrovirus, Calothrix parasitica, Nostoc sp. KVJ20, Anabaena sp. ATCC 33047, Fibrobacter sp. UWB13 and sp. UWB5, Lachnospiraceae bacterium G41, and Xanthomonas arboricola were increased in HE. In conclusion, HE might have an effect to change the rumen microbial community in Holstein cows.

To gather information on the indoor air quality of the greenhouses used for edible oakwood mushroom cultivation, temperature, humidity, and bacterial concentration and species were investigated in 2015 and 2016 in 21 mushroom greenhouses located in ten different regions in Korea. Temperature and humidity of all the mushroom greenhouses ranged from 16.2 to 30.8°C and from 28.2 to 85.6%, respectively. Bacterial concentration exceeded the Korean indoor air quality standard value (800 cfu/m3) in 15 of the 21 mushroom greenhouses. A total of 33 genera and 76 species were identified in the indoor air of the mushroom greenhouses investigated. Of the identified bacteria, 10 genera and 15 species including Acidovorax oryzae, Bacillus infantis, B. licheniformis, Cellulosimicrobium funkei, Ewingella Americana, Exiguobacterium sibiricum, Leclercia adecarboxylata, Lysinibacillus sphaericus, Pseudomonas fulva, Raoultella terrigena, Staphylococcus cohnii, S. haemolyticus, S. saprophyticus, S. sciuri, and Streptomyces sindenensis are among those known to have a harmful effect on human health. These bacteria have been reported to cause sepsis, skin infection, bloodstream infection, bacteremia, spondylitis, peritonitis, acute meningitis, endocarditis and urinary tract infection. The results of this study indicate that continuous hygiene management of indoor air is necessary in the greenhouses used for oakwood mushroom cultivation.

To obtain information on the sanitary of indoor environment in greenhouses used for shiitake cultivation, bacteria associated with larvae and imagoes of Sciaridae flies, pest to shiitake mushroom, were isolated and identified. A total of 1,048 bacterial colonies were isolated from the flies’ larvae and 984 bacterial colonies were isolated from the flies’ imagoes. Based on molecular analysis of the 16S rDNA sequence, Achromobacter xylosoxidans and Tetrathiobacter kashmirensis of β-proteobacteria, Enterobacter asburiae and Raoultella ornithinolytica of γ -proteobacteria, Curtobacterium sp. and Microbacterium thalassium of Actinobacteria, and Penibacillus taichungensis of Firmicutes were identified from the colonies of the flies’ larvae. While, Bacillus megaterium, B. thuringiensis, Lysinbacillus sphaericus and L. fusifomis of Firmicutes, Microbacterium thalassium and Citricoccus parietis of Actinobacteria, and Enterobacter asburiae of γ-proteobacteria were identified from the flies’ imagoes. Some of the isolated bacterial species were known be human pathogens. Overall, the results of this study suggested that mushroom fly carrying human pathogenic bacteria is one of sources impact on the sanitary of indoor environment of greenhouses used for shiitake cultivation.

To obtain information on the sanitary condition of indoor environment in greenhouses used for shiitake cultivation, bacteria associated with larvae and imagoes of Sciaridae flies, a pest to shiitake mushroom, were isolated and identified. A total of 1,048 bacterial colonies were isolated from the flies’ larvae and 984 bacterial colonies were isolated from the flies’ imagoes. Based on the molecular analysis of the 16S rDNA sequence, Achromobacter xylosoxidans and Tetrathiobacter kashmirensis of betaproteobacteria, Enterobacter asburiae and Raoultella ornithinolytica of gammaproteobacteria, Curtobacterium sp. and Microbacterium thalassium of Actinobacteria, and Penibacillus taichungensis of Firmicutes were identified from the colonies of the flies’ larvae. On the other hand, Bacillus megaterium, B. thuringiensis, Lysinbacillus sphaericus and L. fusifomis of Firmicutes, Microbacterium thalassium and Citricoccus parietis of Actinobacteria, and Enterobacter asburiae of gammaproteobacteria were identified from the flies’ imagoes. Some of the isolated bacterial species were known to be human pathogens. Overall, the results of this study suggested that mushroom fly carrying human pathogenic bacteria is one of factors affecting the sanitary of indoor environment of greenhouses used for shiitake cultivation.

The objective of this study was to know the in vitro effects of supplemental anthelmintic plant extracts on the inhibition of protozoa for reducing methane production in the rumen. A fistulated Holstein cow was used as a donor of rumen fluid. The plant extracts (Lonicera japonica, Zanthoxylum piperitum, Pyrethrum, Torreya nucifera, Ruta graveolens) known to have anthelmintic effect were added to the in vitro fermentation bottles containing the rumen fluid and medium. The rumen protozoal population was depressed by the addition of Pyrethrum, Torreya nucifera and Ruta graveolens. The methane production was also significantly (p<0.05)reduced by addition of Pyrethrum (2.20 ml/g DM), Torreya nucifera (2.36 ml/g DM) and Ruta graveolens (2.20 ml/g DM). The microbial growth in the treatments of Ruta graveolens or anthoxylum piperitum was the greatest after 12 h and 24 h incubations, respectively. The results of this study indicated that anthelmintic plant extracts appeared to reduce methane production by inhibition of ruminal protozoa related with the methanogens living endosymbiotic in protozoal cells.

This study was performed to investigate the bacterial diversity isolated from the twospotted spider mite and to interpret their correlation between insect bacteria and acaricide resistance. Twospotted spider mite, Tetranychus urticae was used the resistance strains, which developed over eight years to the six acaricides such as abamectin, acequinocyl, bifenozate, etoxazole, fenpropathrin, and pyridaben, respectively. After cultivating the bacteria from body maceration, bacterial colony was selected and identified through 16S rRNA gene sequences. We are identified six genus from Pyridaben resistant strain, five genus from acequinocyl, three genus from abamectin, bifenozate, etoxazole, and two genus from fenpropathrin. However, we could not found correlation between bacterial density and diversity (phylotypes) among these resistant strains. By analyzing the diversity of population microorganisms, fenpropathrin was showed 40% of Cs value (Similarity coefficient) with susceptible strain, however, abamectin and pyridaben were perfectly different (0%) with susceptible strain. It remains to be learned about how microorganisms co-evolutionary developed with their host insect correlating to the resistance and how microorganisms play role in acaricide resistant mite.

Oral cavity offers a good environment for the bacterial growth. 까le species diversity of oral bacteria has been studied for many years based on the classification of liable bacteria. In order to acquire more comprehensive insight into the baα.erial community of human oral cavity, we used molecular ecological methods to clone 16S rDNAs from human saliva. DNA was direαly extracted from saliva collection of human according to age. By 27F, 1492R primer for 16s rDNA’s amplification were enforced. Cloning was achieved from the amplified DNA using pGEM-T Easy Veαor and competent cellJM 109. 159 different base sequences were obtained from saliva samples of four different persons, chosen according to the age group. In all samples, Streptococcus sp. were the most abundant rnicrobes, followed by Prevotella sp., except in the saliva of an old person where Rothia sp. presented the second dominant group 까lis saliva sample showed another and more irnportant characteristics that there were increased species diversity, from pathogenic bacteria like Haemophilus sp. and lautropia sp. to the higher pr'φ。rtion of unculturable bacteria. The same tendency, but less clearly, was found for the saliva of adult smoker in the forties. These results suggest that environmental factors in the oral caviψ of smoker and older person makes favourable condition for the infectious bacteria.

서울시 소재 지하수 중 중금속으로 오염되어 음용수 이외의 생활 용수로 사용하고 있는 1개 정점과 음용수로 사용하고 있는 1개 정점, 대조군으로 강화도 천연 동굴의 1개 정점을 대상으로 실험을 실시하였다. 지하수 세균군집의 유전적 다양성의 변화를 보기 위해 지하수 세균 군집에서 16SrDNA를 증폭하는 primer로 PCR(polymerase chain reaction)을 실시한 후 ARDRA(amplified ribosomal DNA restrictio

Background : Endophytes are generally regarded as beneficial microorganisms that live in plant tissues without disease symptoms. The endophytic species may differ depending on the plant age, the sampled time, the plant genotype, and the tissue. Although numerous endophytes have been identified from various plants, little is known about the endophytic bacteria of Panax quinquefolius, a useful herb plant. Therefore, the aim of this study is to investigate diversity and distribution of endophytic bacteria from 2-years-old to 6-years-old P. quinquefolius and to evaluate antimicrobial activity of isolates. Methods and Results : Initially, 2-years-old to 6-years-old plants were collected and sterilized with 70% ethanol and sodium hypochlorite, subsequently we prepared individual suspensions which were mixed with sample and sterile distilled water. A total of 88 single colonies were obtained from the LB agar plates spreading suspension. Using 16S rDNA sequencing, the taxonomic status of the isolates were determined consequently 42 species were identified. The 42 species were classified into 4 phylum; Proteobacteria (64%), Firmicute (27%), Actinobacteria (8%), and Bacteroidetes (1%). Based on age, the isolates of 5-years-old plant showed highest diversity. Moreover, Actinomycetales, Bacillales, and Pseudomonadales were equally dispersed as predominant orders in 5-years-old plant. The antagonistic activities of isolates against a phytopathogen, Pseudomonas syringae pv. tomato DC3000 : GFP (Pst : GFP) were performed using dual culture assays. We measured antibacterial activity by quantifying fluorescence of Pst:GFP which representing pathogen growth. As a result, 36 isolates inhibited growth of Pst:GFP. Interestingly, all species belonging Pseudomonas in this study showed strong antibacterial activity against Pst : GFP. Conclusion : These results improve our understanding of the structure and diversity of the endophytic bacteria of P. quinquefolius. Furthermore, we suggest that bacterial endophytes with antimicrobial activity might have useful as materials for biocontrol agents.