1.The novel species and genus discovered and nominated from the human oral cavity in 2009--2012.
Xiaorong XIAO ; Yan LI ; Liying XIAO
West China Journal of Stomatology 2013;31(2):217-220
Bacterium is dominant microflora population in human oral cavity, and the novel species and novel genus were discovered and named one after another. This article reviewed the major biological characteristics of 5 novel genus and 16 novel species isolated from the human oral cavity from 2009 to 2012.
Bacteria
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classification
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isolation & purification
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Humans
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Mouth
2.Isolation of bacteria with plant growth-promoting activities from a foliar biofertilizer
Xin Yen Tor ; Wai Keat Toh ; Pek Chin Loh ; Hann Ling Wong
Malaysian Journal of Microbiology 2022;18(3):315-321
Aims:
Plant growth-promoting bacteria are the key components of a biofertilizer. This study was aimed to isolate and identify the predominant bacteria found in a foliar biofertilizer and characterizes the potential of the bacterial isolates as plant growth promoters.
Methodology and results:
Potential bacteria with plant growth-promoting activities were isolated from a foliar biofertilizer on HiCrome™ Bacillus agar and Nutrient agar. Bacteria with unique colonial morphology were selected and categorized by Gram’s differential staining. Subsequently, the bacterial isolates were being further characterized for plant growth-promoting potentials, such as the production of indole acetic acid (IAA), 1-aminocyclopropane-1-carboxylate (ACC) deaminase and siderophore; as well as the ability of nitrogen fixation and phosphate/potassium solubilization. Based on the characterized traits, three bacterial isolates, namely M17, M22 and M52 showed great potential for being a plant growth promoter. Based on their 16S rRNA gene sequence analysis, M17, M22 and M52 were identified as Leclercia adecarboxylata, Margalitia shackletonii and Lysinibacillus pakistanensis, respectively.
Conclusion, significance and impact of study
Bacterial isolates exhibiting plant growth-promoting activities were successfully isolated from a biofertilizer and identified in this study. This finding provides an insight into the potential bacteria of a foliar fertilizer that may promote plant growth. Identification of these plant-growth promoters may help the scientists and agrochemical manufacturers to determine and disclose the key microorganisms of their biofertilizers, thereby contributing to the improvement of biofertilizers and promoting them as reliable alternatives to chemical fertilizers.
Bacteria--isolation &
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purification
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Fertilizers--microbiology
4.Clinical Relevance of Time-to-positivity in BACTEC9240 Blood Culture System.
Sang Hyuk PARK ; Hyoeun SHIM ; Nam Seop YOON ; Mi Na KIM
The Korean Journal of Laboratory Medicine 2010;30(3):276-283
BACKGROUND: Continuous monitoring systems have allowed determination of the time-to-positivity (TTP). We evaluated the clinical relevance of TTP in the BACTEC9240 system (Becton-Dickinson, USA). METHODS: A total of 2,354 vials of positive blood cultures were evaluated over 2 months. TTP was monitored from each of BACTEC Plus Aerobic/F (BD) or Pediatric Plus/F and Lytic Anaerobic/F bottles, and the differential time-to-positivity (DTP) for blood samples drawn simultaneously via catheter and a peripheral site was determined. RESULTS: The average TTP of the positive vials was 17.4 hr, and 79.9% and 95.2% of the vials showed positivity within 24 and 48 hr, respectively. While the average TTP values for Aeromonas hydrophila, Bacillus cereus, Acinetobacter baumannii, and Streptococcus pneumoniae were less than 10 hr, those for Candida spp., anaerobes, Propionibacterium acnes, Corynebacterium spp, Bacillus spp. other than cereus, and coagulase-negative staphylococci were 35.3, 27.0, 56.8, 45.8, 23.0, and 26.3 hr, respectively. The negative predictive values of TTP over 24 hr to predict Staphylococcus aureus among staphylococci and S. pneumoniae among alpha-hemolytic streptococci were 76.7% and 100%, respectively. Enterobacteriaceae and Enterococcus faecalis showed shorter TTP in anaerobic vials than in aerobic vials. DTP of more than 2 hr was observed for 27.8%, 72.2%, and 45.5% of S. aureus, S. epidermidis, and Candida spp. CONCLUSIONS: TTP can be used to discriminate pathogens and contaminants. The shorter TTP in anaerobic vials of certain Enterobacteriaceae and Enterococcus spp. would facilitate further identification. DTP is useful for diagnosing catheter-related bloodstream infection by S. aureus, S. epidermidis, and Candida spp.
Bacteremia/*diagnosis
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Bacteria, Aerobic/isolation &purification
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Bacteria, Anaerobic/isolation &purification
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Bacteriological Techniques/instrumentation/methods
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Humans
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Reagent Kits, Diagnostic
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Time Factors
5.Removal of nitrogen, phosphorus, and organic pollutants from water using seeding type immobilized microorganisms.
Lin WANG ; Li-Jing HUANG ; Luo-Jia YUN ; Fei TANG ; Jing-Hui ZHAO ; Yan-Qun LIU ; Xin ZENG ; Qi-Fang LUO
Biomedical and Environmental Sciences 2008;21(2):150-156
OBJECTIVETo study the possibility of removing nitrogen, phosphorus, and organic pollutants using seeding type immobilized microorganisms.
METHODSLakes P and M in Wuhan were chosen as the objects to study the removal of nitrogen, phosphorus, and organic pollutants with the seeding type immobilized microorganisms. Correlations between the quantity of heterotrophic bacteria and the total nitrogen (TN), total phosphorus (TP), and total organic carbon (TOC) in the two lakes were studied. The dominant bacteria were detected, inoculated to the sludge and acclimated by increasing nitrogen, phosphorus and decreasing carbon source in an intermittent, time-controlled and fixed-quantity way. The bacteria were then used to prepare the seeding type immobilized microorganisms, selecting diatomite as the adsorbent carrier. The ability and influence factors of removing nitrogen, phosphorus, and organic pollutant from water samples by the seeding type immobilized microorganisms were studied.
RESULTSThe coefficients of the heterotrophic bacterial quantity correlated with TOC, TP, and TN were 0.9143, 0.8229, 0.7954 in Lake P and 0.9168, 0.7187, 0.6022 in Lake M. Ten strains of dominant heterotrophic bacteria belonging to Pseudomonas, Coccus, Aeromonas, Bacillus, and Enterobateriaceae, separately, were isolated. The appropriate conditions for the seeding type immobilized microorgansims in purifying the water sample were exposure time=24 h, pH=7.0-8.0, and quantity of the immobilized microorganisms=0.75-1 g/50 mL. The removal rates of TOC, TP, and TN under the above conditions were 80.2%, 81.6%, and 86.8%, respectively.
CONCLUSIONThe amount of heterotrophic bacteria in the two lakes was correlated with TOC, TP, and TN. These bacteria could be acclimatized and prepared for the immobilized microorganisms which could effectively remove nitrogen, phosphorus, and mixed organic pollutants in the water sample.
Bacteria ; metabolism ; Environmental Pollutants ; isolation & purification ; Nitrogen ; isolation & purification ; Organic Chemicals ; isolation & purification ; Phosphorus ; isolation & purification ; Water Microbiology
6.Isolation of endophytic bacteria in roots of Panax ginseng and screening of antagonistic strains against phytopathogens prevalent in P. ginseng.
Yong LI ; Dongyue ZHAO ; Wanlong DING ; Yixin YING
China Journal of Chinese Materia Medica 2012;37(11):1532-1535
In this study, endophytic bacteria were isolated from roots of P. ginseng by plate culture method, and as a result, 40 endophytic bacterial strains were isolated, Bacillus spp. and Pseudomonas spp. were predominant. By confront culture method, two antagonistic endophytic bacterial strain, ge15 (Stenotrophomonas maltophilia) and ge25 (Bacillus sp. ) against Cylindrocarpon destructans, Sclerotinia schinseng and Alternaria pana were identified. The inhibition zone of ge15 to them were 5.5, 22.0, 14.8 mm, respectively; and which were 12.7,16.5,9.0 mm for ge25. The Results indicate that endophytic bacteria have biocontrol potential on ginseng pathogens, and which can be used as a bio-control factor on ginseng soilborne diseases control.
Bacteria
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isolation & purification
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Bacterial Physiological Phenomena
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Endophytes
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isolation & purification
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physiology
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Panax
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microbiology
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Plant Roots
;
microbiology
7.Separation of magnetic bacteria by using a magnetic separator.
Xinxing LIU ; Ning GUO ; Yingjie YANG ; Wanjie LIANG ; Jian ZHANG
Chinese Journal of Biotechnology 2010;26(2):270-275
A magnetic separator was used to separate magnetic bacteria based on their magnetotactic characteristics. Acidithiobacillus ferrooxidans, a bacterium that could synthesize intra-cellular nanometer magnetic particles, was investigated as an example. Strong magnetic and weak magnetic cells were separated and collected. On average, the number of the magnetic particles present in the strong magnetic cells is more than that of the weak magnetic cells. Moreover, semisolid-plate magnetophoresis showed that the magnetotaxis of strong magnetic cells was stronger than the weak magnetic cells. These results suggest that the magnetic separator can be used to isolate the magnetic bacteria, which will facilitate the research of magnetic bacteria.
Acidithiobacillus
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isolation & purification
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metabolism
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Bacteria
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isolation & purification
;
metabolism
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Bacterial Physiological Phenomena
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Bacteriological Techniques
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methods
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Magnetics
8.Actinomyces Israelii and Eikenella Corrodens Isolation from a Pleura1 Effusion Case.
Yunsop CHONG ; Suck Hee LEE ; Samuel Y LEE
Yonsei Medical Journal 1972;13(1):50-59
Actionomyces israelii and Eikenella corrodens were isolated from the pleural effusion of a 69 year o1d male suspected of pulmonary tuberculosis. Acid fast bacillus was not found from any clinical specimens, thereby the case was considered one of the rare forms of actinomycosis accompanied by E. corrodens. Studies were made on the morphologies, cultural characters and biochemical reactions and identification of the isolates were made on the basis of the results. The identifications of A. israelii and E. corrodens were confirmed by J. M. Slack and by R. E. Weaver, respectively.
Actinomyces/isolation & purification*
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Aged
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Bacteria/isolation & purification*
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Human
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Male
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Pleural Effusion/microbiology*
9.Screening and identification of indoleacetic acid producing endophytic bacterium in Panax ginseng.
Yun JIANG ; Lei TIAN ; Chang-qing CHEN ; Guan-jun ZHANG ; Tong LI ; Jing-xiu CHEN ; Xue WANG
China Journal of Chinese Materia Medica 2015;40(2):213-217
Endophytic bacteria which was producing indoleacetic acid was screened from Panax ginseng by using the Salkowski method. The active strain was also tested for its ability of nitrogen fixation by using the Ashby agar plates, the PKV plates and quantitative analysis of Mo-Sb-Ascrobiology acid colorimetry was used to measure its ability of phosphate solubilization, for its ability of potassium solubilization the silicate medium and flame spectrophotometry was used, for its ability of producing siderophores the method detecting CAS was used, for its ability of producing ACC deaminase the Alpha ketone butyric acid method was applied. And the effect on promoting growth of seed by active strain was tested. The results showed that the indoleacetic acid producing strain of JJ5-2 was obtained from 118 endophytes, which the content of indoleacetic acid was 10.2 mg x L(-1). The JJ5-2 strain also had characteristics of phosphate and potassium solubilization, nitrogen fixation, producing siderophores traits, and the promoting germination of ginseng seeds. The JJ5-2 strain was identified as Bacillus thuringiensis by analyzing morphology, physiological and biochemical properties and 16S rRNA gene sequences.
Bacteria
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isolation & purification
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metabolism
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Endophytes
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isolation & purification
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metabolism
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Indoleacetic Acids
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metabolism
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Panax
;
microbiology
10.Community structure and difference of endophtic bacteria in Aquilaria sinensis with and without agarwood.
Ya-Li HUANG ; Zao-Yuan KUANG ; Meng-Wei SONG ; Ren ZHANG
China Journal of Chinese Materia Medica 2015;40(1):63-67
Aquilaria sinensis can generate agarwood, which is closely related with endophyte. Up to now, studies mainly focused on the effects of endophytic fungi on agarwood formation, but studies about endophytic bacteria are rarely reported. In our research, the T-RFs and Shannon index of endophytic bacteria in samples of agarwood increase. The number of distinctive T-RFs fragments of corresponding samples in the same group accounted for more than 60% the number of total T-RFs fragments. In samples of no-agarwood, the dominant bacterial population are Anoxybacillus, Clostridium, Candidatus endobugula, Lysinibacillus. In samples of agarwood, the dominant bacterial population are Clostridium, Lysinibacillus, Luteimonas, phytoplasma. Besides, there are. specific T-RFs fragment in samples of agarwood and no-agarwood respectively. When we perform cluster analysis, we found samples of agarwood highly gather together and samples of no-agarwood highly gather together. This means community of endophytic bacteria emerge significant and regular changes during agarwood formation, which may be result of agarwood production, or maybe it is important reason of agarwood production. In this paper, we obtain more comprehensive and accurate community of endophytic bacteria in Aquilaria sinensis and it's variation during agarwood formation using T-RFLP, which is first study of effects of endophytic bacteria on agarwood formation, and will help to exploit resource of endophytic bacteria more reasonably.
Bacteria
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classification
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genetics
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isolation & purification
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Biodiversity
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Endophytes
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classification
;
genetics
;
isolation & purification
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Thymelaeaceae
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microbiology
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Wood
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microbiology