Journal articles on the topic 'Environmental microbial isolates'
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Pacholak, Amanda, Wojciech Smułek, Agnieszka Zgoła-Grześkowiak, and Ewa Kaczorek. "Nitrofurantoin—Microbial Degradation and Interactions with Environmental Bacterial Strains." International Journal of Environmental Research and Public Health 16, no. 9 (April 30, 2019): 1526. http://dx.doi.org/10.3390/ijerph16091526.
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The continuous exposure of living organisms and microorganisms to antibiotics that have increasingly been found in various environmental compartments may be perilous. One group of antibacterial agents that have an environmental impact that has been very scarcely studied is nitrofuran derivatives. Their representative is nitrofurantoin (NFT)—a synthetic, broad-spectrum antibiotic that is often overdosed. The main aims of the study were to: (a) isolate and characterize new microbial strains that are able to grow in the presence of NFT, (b) investigate the ability of isolates to decompose NFT, and (c) study the impact of NFT on microbial cell properties. As a result, five microbial species were isolated. A 24-h contact of bacteria with NFT provoked modifications in microbial cell properties. The greatest differences were observed in Sphingobacterium thalpophilum P3d, in which a decrease in both total and inner membrane permeability (from 86.7% to 48.3% and from 0.49 to 0.42 µM min−1) as well as an increase in cell surface hydrophobicity (from 28.3% to 39.7%) were observed. Nitrofurantoin removal by selected microbial cultures ranged from 50% to 90% in 28 days, depending on the bacterial strain. Although the isolates were able to decompose the pharmaceutical, its presence significantly affected the bacterial cells. Hence, the environmental impact of NFT should be investigated to a greater extent.
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Roane, T. M., and S. T. Kellogg. "Characterization of bacterial communities in heavy metal contaminated soils." Canadian Journal of Microbiology 42, no. 6 (June 1, 1996): 593–603. http://dx.doi.org/10.1139/m96-080.
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Heavy metal pollution is a principle source of environmental contamination. We analyzed heavy metal impacted soil microbial communities and found that, in general, although lead adversely affected biomass, metabolic activity, and diversity, autochthonous lead- and cadmium-resistant isolates were found. In several metal-stressed soils, the microbial community consisted of two populations, either resistant or sensitive to lead. Additionally, a lead-resistant isolate was isolated from a control soil with no known previous exposure to lead, suggesting widespread lead resistance. Lead-resistant genera isolated included Pseudomonas, Bacillus, Corynebacterium, and Enterobacter species. Plasmids, ranging from 5 to 260 kb, were not detected through standard purifications from lead-resistant isolates. Positive correlations existed between antibiotic resistance and isolation habitat for lead-resistant strains, microbial metabolic activity and soil type, soluble lead concentration and microbial diversity, and arsenic concentration and total or viable cell concentrations.Key words: heavy metal, lead, cadmium, soil bacteria, stress, remediation.
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Pattani, Vivek B. "Characterization of Plant Growth-Promoting Activity of Bacteria Isolated from Forest and Coastal Regions of Saurashtra, Gujarat, India." Bioscience Biotechnology Research Communications 15, no. 1 (March 25, 2022): 144–51. http://dx.doi.org/10.21786/bbrc//15.1.22.
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The haphazard application of chemical fertilizers and pesticides causes tremendous damage to ecosystems and all biota. One of the most effective ways to tackle the threat is to use biofertilizer. Plant growth promoting bacteria (PGPB) are an important bacterial source for microbial fertilizers that can boost agricultural yields by encouraging plant growth. Bacterial isolates isolated from Saurashtra region, Gujarat, India were analysed for their capability to solubilize inorganic 'P' from tri calcium phosphate and production of indole acetic acid (IAA) quantitatively by bacterial. Production of ammonia, siderophore and hydrogen cyanide (HCN) by selected bacteria isolates was analysed. Biochemical characterization of selected bacterial isolates was done using Vitek 2 Compact system. Isolate GFS15C2 showed highest amount of phosphate solubilization, followed by isolate GFS07C1 and GFS01C1. Bacterial isolate GFS15C2 produced highest amount of IAA. All bacterial isolates were able produce ammonia. Eight bacteria isolates were be to produce HCN. Siderophore was produced by 14 bacterial isolates. In biochemical characterization all the bacterial isolates were able to use D-glucose. Based on biochemical characters clustering of bacteria isolates was done using Paleontological statistics software package for education and data analysis(PAST). Using cluster analysis by euclidean distance method based on biochemical characterization isolates GFS16C2 & SCS12C3 was found to have distinct characters than other isolates. The present study attempts to characterize PGPB which could be harnessed to improve plant growth. Several phosphate solubilizers and IAA producers also showed production of siderophores and HCN which suggests that these organisms do possess biocontrol ability. These PGPB microbial inoculants can be utilized to improve agricultural systems or as an alternate means of environmentally friendly plant disease biocontrol.
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Buerger, S., A. Spoering, E. Gavrish, C. Leslin, L. Ling, and S. S. Epstein. "Microbial Scout Hypothesis and Microbial Discovery." Applied and Environmental Microbiology 78, no. 9 (February 24, 2012): 3229–33. http://dx.doi.org/10.1128/aem.07308-11.
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ABSTRACTIn this study, we examine the temporal pattern of colony appearance during cultivation experiments, and whether this pattern could inform on optimizing the process of microbial discovery. In a series of long-term cultivation experiments, we observed an expected gradual increase over time of the total number of microbial isolates, culminating in a 700-fold colony count increase at 18 months. Conventional thought suggests that long-term incubations result in a culture collection enriched with species that are slow growing or rare, may be unavailable from short-term experiments, and likely are novel. However, after we examined the phylogenetic novelty of the isolates as a function of the time of their isolation, we found no correlation between the two. The probability of discovering either a new or rare species late in the incubation matched that of species isolated earlier. These outcomes are especially notable because of their generality: observations were essentially identical for marine and soil bacteria as well as for spore formers and non-spore formers. These findings are consistent with the idea of the stochastic awakening of dormant cells, thus lending support to the scout model. The process of microbial discovery is central to the study of environmental microorganisms and the human microbiome. While long-term incubation does not appear to increase the probability of discovering novel species, the technology enabling such incubations, i.e., single-cell cultivation, may still be the method of choice. While it does not necessarily allow more species to grow from a given inoculum, it minimizes the overall isolation effort and supplies needed.
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Clark, Chase M., Linh Nguyen, Van Cuong Pham, Laura M. Sanchez, and Brian T. Murphy. "Automated Microbial Library Generation Using the Bioinformatics Platform IDBac." Molecules 27, no. 7 (March 22, 2022): 2038. http://dx.doi.org/10.3390/molecules27072038.
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Libraries of microorganisms have served as a cornerstone of therapeutic drug discovery, though the continued re-isolation of known natural product chemical entities has remained a significant obstacle to discovery efforts. A major contributing factor to this redundancy is the duplication of bacterial taxa in a library, which can be mitigated through the use of a variety of DNA sequencing strategies and/or mass spectrometry-informed bioinformatics platforms so that the library is created with minimal phylogenetic, and thus minimal natural product overlap. IDBac is a MALDI-TOF mass spectrometry-based bioinformatics platform used to assess overlap within collections of environmental bacterial isolates. It allows environmental isolate redundancy to be reduced while considering both phylogeny and natural product production. However, manually selecting isolates for addition to a library during this process was time intensive and left to the researcher’s discretion. Here, we developed an algorithm that automates the prioritization of hundreds to thousands of environmental microorganisms in IDBac. The algorithm performs iterative reduction of natural product mass feature overlap within groups of isolates that share high homology of protein mass features. Employing this automation serves to minimize human bias and greatly increase efficiency in the microbial strain prioritization process.
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Milic, Jelena, Jelena Avdalovic, Tatjana Solevic-Knudsen, Gordana Gojgic-Cvijovic, Tanja Jednak, and Miroslav Vrvic. "Initial microbial degradation of polycyclic aromatic hydrocarbons." Chemical Industry and Chemical Engineering Quarterly 22, no. 3 (2016): 293–99. http://dx.doi.org/10.2298/ciceq150606043m.
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The group of polycyclic aromatic hydrocarbons (PAHs) are very hazardous environmental pollutants because of their mutagenic, carcinogenic and toxic effects on living systems. The aim of this study was to examine and compare the ability and efficiency of selected bacterial isolates obtained from oil-contaminated areas to biodegrade PAHs. The potential of the bacteria to biodegrade various aromatic hydrocarbons was assessed using the 2,6-dichlorophenol-indophenol assay. Further biodegradation of PAHs was monitored by gravimetric and gas-chromatographic analysis. Among the eight bacterial isolates, identified on the basis of 16S rDNA sequences, two isolates, Planomicrobium sp. RNP01 and Rhodococcus sp. RNP05, had the ability to grow on and utilize almost all examined hydrocarbons. Those isolates were further examined for biodegradation of phenanthrene and pyrene, as single substrates, and as a mixture, in vitro for ten days. After three days, both isolates degraded a significant amount phenanthrene, which has a simpler chemical structure than pyrene. Planomicrobium sp.RNP01 commenced biodegradation of pyrene in the PAH mixture only after it had almost completly degraded phenanthrene. The isolated and characterized bacteria, Planomicrobium sp. RNP01 and Rhodococcus sp. RNP05, have shown high bioremediation potential and are likely candidates to be used for degradation of highly toxic PAHs in contaminated areas.
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Vaish, S., N. Garg, and I. Z. Ahmad. "Bioprospecting of microbial isolates from biodynamic preparations for PGPR and biocontrol properties." Journal of Environmental Biology 42, no. 3 (May 4, 2021): 644–51. http://dx.doi.org/10.22438/jeb/42/3/mrn-1529.
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Aim: To study the role of microorganisms behind their bioenhancing, biocontrol properties, their enzymatic potential, and characterization of high performing microbial isolates on molecular basis. Methodology: Dominant culturable microbes including bacteria and fungi were isolated from biodynamic preparations and screened on the basis of plant-growth promoting (PGP) activities viz., ammonia production, phosphate solubilization, siderophore production, hydrogen cyanide production, seed germination efficacy and biocontrol properties. The dominant and effective microorganisms were screened for enzymes activities viz., pectinase, cellulase and amylase. The selected bacterial and fungal isolates, exhibiting higher enzyme activities, were subjected to molecular characterization. Results: Out of 68 bacterial and 25 fungal isolates from 8 biodynamic preparations (BD 500 - BD 507), 15 bacterial isolates exhibited high plant growth promoting activities while 10 bacterial isolates exhibited biocontrol activity against pathogens. Bacillus licheniformis isolated from BD 504, expressed high pectinase (2.595 U ml-1 min-1), cellulase (0.308 U ml-1 min-1) and amylase (0.418 U ml-1 min-1) activities. Fungal isolates with high enzymatic activities, were isolated from BD 500, 503 and 506, respectively. Interpretation: Microorganism isolates from biodynamic preparations possessed strong plant growth promoting, biocontrol and enzymatic properties, which might be responsible for the efficacy of organic preparations under field conditions.
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Munir, E., A. Lutfia, A. Hartanto, A. A. N. Fazri, C. Herdiyanti, R. Pratama, O. B. I. Sinaga, Z. A. Ramadani, and P. Hasanah. "Potential of landfill microbes in hydrocarbon degradation." IOP Conference Series: Earth and Environmental Science 977, no. 1 (June 1, 2022): 012095. http://dx.doi.org/10.1088/1755-1315/977/1/012095.
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Abstract Bioprospecting study of indigenous microbial community is still being approached especially for some microbial strains in bioremediation aspect. The objective of this study was to obtain a collection of indigenous bacterial and fungal isolates capable of growing on hydrocarbon medium. Soil samples were collected from Terjun Landfill located in Medan City, North Sumatra. Mineral salt agar medium supplemented with 10% (v/v) of hydrocarbon sources (diesel oil, pesticide, dye wastewater) was used to screen the microbial capacity in utilizing the hydrocarbon compounds as sole carbon source. Each isolate was categorized based on their growth performance or colony diameter on agar medium namely none (-), slow (+), moderate (++), and rapid (+++). The results obtained a total of 27 bacterial isolates and 6 fungal isolates. Majority of microbial isolates showed a better growth on pesticide medium than in diesel oil and dye wastewater which indicated their capability in converting the pesticide as nutrient. It is worthwhile to investigate the further application of our indigenous strains in contaminated areas in order to ensure the environmental sustainability.
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Kumari, Kiran, R. C. Aanad, and Neeru Narula. "Microbial degradation of polyethylene (PE)." South Pacific Journal of Natural and Applied Sciences 27, no. 1 (2009): 66. http://dx.doi.org/10.1071/sp09012.
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Thirty two bacterial isolates were obtained from soil by soil burial method followed by enrichment culture technique in film culturing (FC) media. Bacterial isolates differing in morphology were selected, purified and maintained at 4°C. Thirty % of these isolates were found to be Gram negative and 50% showed positive starch hydrolysis test and were screened for their ability to degrade Low Density Polyethylene (untreated, UV and heat strips) in film culturing media and percent weight loss of polyethylene after 4th week was determined. Among various isolates, highest degradation was by Is 3, Is 22 and Is 31 to the range of 25–27%, of UV treated polyethylene strips. High temperature (40°C), was found to enhance degradation rate of polyethylene more effectively by 24–28% compared to low temperature at 30°C (18–21%). Degradation of treated polyethylene strips (UV, heat steam) was up to 4% by compost treatment as studied by using CO2 evolution, an estimation tool to analyze % degradation. Bacterial activity was also affected by various environmental factors like sunlight, temperature, oxygen etc.
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Munir, Neelma, Kanza Malik, Rasheeda Bashir, Imran Altaf, and Shagufta Naz. "Isolation and Characterization of Polysaccharide- Degrading Microbes from Compost Samples." Journal of Environmental Science and Management 24, no. 2 (December 31, 2021): 10–16. http://dx.doi.org/10.47125/jesam/2021_2/02.
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This study isolated and identified novel microbial polysaccharide degrading species involved in composting process. Bacteria were isolated from different composting samples from Lahore Compost Private Limited, Lahore, Pakistan. Physico-chemical analysis of compost samples made from municipal waste were collected at 15-day interval during the composting process. A total of 55 bacteria were isolated and identified using morphological and biochemical characteristics. Out of 55 isolates, 26 mesophilic and 14 thermophilic had cellulose degrading potential. Out of 26 mesophyllic bacterial isolates, 20 were found cellulolytic. The isolated bacteria and fungi were identified morphologically and biochemically. The highest potential to degrade cellulose was recorded from four Bacillus strains. Molecular characterization of potential cellulolytic bacteria by 16S rRNA was performed. Bacillus sp. were found as the most prevalent cellulolytic bacteria in composting process. Fungi were also isolated and characterized morphologically and microscopically following techniques. The potential cellulolytic fungal isolates were Aspergillus fumigatus, Mucor sp., Saccharomyces sp., and Aspergillus niger. The results of this study would be helpful in highlighting the potential role of different microbes involved in enhancement of the composting process. These microbes can be used for the preparation of microbial inoculum based on their polysaccharide cellulose, bacteria, composting degrading ability.
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Hammes, Frederik, Nico Boon, Johan de Villiers, Willy Verstraete, and Steven Douglas Siciliano. "Strain-Specific Ureolytic Microbial Calcium Carbonate Precipitation." Applied and Environmental Microbiology 69, no. 8 (August 2003): 4901–9. http://dx.doi.org/10.1128/aem.69.8.4901-4909.2003.
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ABSTRACT During a study of ureolytic microbial calcium carbonate (CaCO3) precipitation by bacterial isolates collected from different environmental samples, morphological differences were observed in the large CaCO3 crystal aggregates precipitated within bacterial colonies grown on agar. Based on these differences, 12 isolates were selected for further study. We hypothesized that the striking differences in crystal morphology were the result of different microbial species or, alternatively, differences in the functional attributes of the isolates selected. Sequencing of 16S rRNA genes showed that all of the isolates were phylogenetically closely related to the Bacillus sphaericus group. Urease gene diversity among the isolates was examined by using a novel application of PCR-denaturing gradient gel electrophoresis (DGGE). This approach revealed significant differences between the isolates. Moreover, for several isolates, multiple bands appeared on the DGGE gels, suggesting the apparent presence of different urease genes in these isolates. The substrate affinities (Km ) and maximum hydrolysis rates (V max) of crude enzyme extracts differed considerably for the different strains. For certain isolates, the urease activity increased up to 10-fold in the presence of 30 mM calcium, and apparently this contributed to the characteristic crystal formation by these isolates. We show that strain-specific calcification occurred during ureolytic microbial carbonate precipitation. The specificity was mainly due to differences in urease expression and the response to calcium.
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Carlson, Hans, Adam Deutschbauer, and John Coates. "Microbial metal resistance and metabolism across dynamic landscapes: high-throughput environmental microbiology." F1000Research 6 (June 29, 2017): 1026. http://dx.doi.org/10.12688/f1000research.10986.1.
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Multidimensional gradients of inorganic compounds influence microbial activity in diverse pristine and anthropogenically perturbed environments. Here, we suggest that high-throughput cultivation and genetics can be systematically applied to generate quantitative models linking gene function, microbial community activity, and geochemical parameters. Metal resistance determinants represent a uniquely universal set of parameters around which to study and evaluate microbial fitness because they represent a record of the environment in which all microbial life evolved. By cultivating microbial isolates and enrichments in laboratory gradients of inorganic ions, we can generate quantitative predictions of limits on microbial range in the environment, obtain more accurate gene annotations, and identify useful strategies for predicting and engineering the trajectory of natural ecosystems.
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Icgen, Bulent, Salih Batuhan Salik, Lale Goksu, Huseyin Ulusoy, and Fadime Yilmaz. "Higher alkyl sulfatase activity required by microbial inhabitants to remove anionic surfactants in the contaminated surface waters." Water Science and Technology 76, no. 9 (July 7, 2017): 2357–66. http://dx.doi.org/10.2166/wst.2017.402.
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Abstract Biodegradation of anionic surfactants, like sodium dodecyl sulfate (SDS) are challenged by some bacteria through the function of the enzyme alkyl sulfatases. Therefore, identifying and characterizing bacteria capable of degrading SDS with high alkyl sulfatase enzyme activity are pivotal. In this study, bacteria isolated from surfactant contaminated river water were screened for their potential to degrade SDS. Primary screening carried out by the conventional enrichment culture technique and assessment of SDS-degrading ability through methylene blue active substance assay revealed 12, out of 290, SDS-degrading surface water bacteria with maximum SDS degrading abilities of 46–94% in 24–54 h. The isolates exhibited optimum growth at SDS concentration of 1 g/L, but tolerated up to 15–75 g/L. Eleven isolates were identified as the species of Pseudomonas and one isolate was identified as Aeromonas through 16S rRNA sequencing. Proteolytic activity of alkyl sulfatases in the identified isolates was shown by using native-PAGE analysis. The determined enzyme activities changed in between 1.32 and 2.90 U/mg in the crude extracts. Preliminary experiments showed that the isolates with the alkyl sulfatase enzyme activities ≥2.50 U/mg were strong gratuitous degraders. However, their relative importance in soil, sewage, and wastewater treatment plants remains to be assessed.
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Rahaman, M. Mizanur, M. Nur Hossain, Nantu Chandra Das, Monzur Morshed Ahmed, and M. Mahfuzul Hoque. "Potential Thermotolerant Lactobacilli Isolated from Chicken Gastrointestinal Tract for Probiotic Use in Poultry Feeds." Bangladesh Journal of Microbiology 36, no. 2 (February 19, 2020): 63–68. http://dx.doi.org/10.3329/bjm.v36i2.45529.
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This research was carried out to isolate and identify thermotolerant lactobacilli from broiler chicken gastrointestinal tract from Dhaka, Bangladesh. Twenty five thermotolerant Lactobacillus strains were isolated and identified as Lactobacillus species based on cultural characteristics, biochemical tests, and sugar fermentation. The probiotic are a live microbial feed supplements which positively affects the health of the host animal by improving its intestinal balance.The results showed only four among twenty five isolates were highly responded to probiotic criteria such as low pH tolerance (2.5), bile salt tolerance (2%) and sodium chloride salt tolerance (5%) in vitro, and were identified strains as Lactobacillus plantarum img-02, Lactobacillus plantarum img-08, Lactobacillus plantarum img-10 and Lactobacillus acidophilus img-14 according to Bergey’s Manual of Systematic Bacteriology. Four isolates grow enough at 45°C and two isolates (Lactobacillus plantarum img-10 and Lactobacillus acidophilus img-14) heat stable at 60°C for 30 min. All the strains were showed protease activity on skim milk agar. These strains were resistance to commercial antibiotic ciprofloxacin, gentamycin, imipenem and penicillin G but sensitive to ampicillin, doxycycline, erythromycin and tetracycline; also have antimicrobial activity against common pathogen such as ATCC of Salmonella enteritidis, Staphylococcus aureus, Listeria monocytogenes, Shigella flexneri, Bacillus cereus, Klebsiella pneumonia, Escherichia coli (environmental isolates), Aspergillus flavus and Candida albicans. This study concludes that these isolates may be used as potential candidate as probiotic poultry feed.
Bangladesh J Microbiol, Volume 36 Number 2 December 2019, pp 63-68
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Tormoehlen, Kristin, Yvette J. Johnson-Walker, Emily W. Lankau, Maung San Myint, and John A. Herrmann. "Considerations for studying transmission of antimicrobial resistant enteric bacteria between wild birds and the environment on intensive dairy and beef cattle operations." PeerJ 7 (February 27, 2019): e6460. http://dx.doi.org/10.7717/peerj.6460.
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Background Wild birds using livestock facilities for food and shelter may contribute to dissemination of enteric pathogens or antimicrobial resistant bacteria. However, drivers of microbial exchange among wildlife and livestock are not well characterized. Predisposition for acquiring and retaining environmental bacteria may vary among species because of physiologic or behavioral differences, complicating selection of a bacterial model that can accurately characterize microbial connections among hosts of interest. This study compares the prevalence and antibiotic resistance phenotypes of two potential model bacterial organisms isolated from wild birds and their environments. Methods We compared prevalence and resistance profiles of Escherichia coli and Enterococcus species isolated from environmental swabs and bird feces on a residential control site, a confinement dairy, a pasture-based beef farm, and a confinement beef farm. Results Bird feces at all sites had low-to-moderate prevalence of Escherichia coli (range: 17–47%), despite potential for exposure on farms (range: 63–97%). Few Escherichia coli were isolated from the control environment. Enterococcus faecalis was dominant in birds at both beef farms (62% and 81% of Enterococcus isolates) and low-to-moderately prevalent at the dairy and control sites (29% and 23% of isolates, respectively). Antimicrobial resistance prevalence was higher in farm samples compared to those from the residential control, but distribution of resistant isolates varied between the bacterial genera. Birds on all farms carried resistant Enterococcus at similar rates to that of the environment, but resistance was less common in bird-associated Escherichia coli despite presence of resistant isolates in the farm environment. Discussion Bacterial species studied may affect how readily bacterial exchange among populations is detected. Selection of microbial models must carefully consider both the questions being posed and how findings might influence resulting management decisions.
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Karmakar, Joydip, Sayani Goswami, Krishnendu Pramanik, Tushar Kanti Maiti, Rup Kumar Kar, and Narottam Dey. "Growth promoting properties of Mycobacterium and Bacillus on rice plants under induced drought." Plant Science Today 8, no. 1 (January 1, 2021): 49–57. http://dx.doi.org/10.14719/pst.2021.8.1.965.
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Management of drought stress through application of plant growth promoting rhizobacteria (PGPR) is now considered as an effective strategy in the present scenario of altered environmental conditions of the world. The aims and objectives of the present investigation was isolation, characterization and identification of some potential microbial resources (PGPR) from drought-affected upland rice fields of South Bengal followed by experimentation on the effect of isolated PGPR on drought induced rice seedlings. Selected isolates were isolated from rice field rhizospheric soils and tested for their PGPR activity, through phosphate solubilization, nitrogen fixation, IAA production and ACC deaminase activity. Then, the selected isolates were identified through 16S rDNA sequencing and phylogenetic analysis. Among the screened isolates two (isolate 1 and isolate 6) showing plant growth promoting traits, was applied on studied germplasm (IR64) to find out the influence of the applied organisms on rice growth and development under induced drought. Both organisms showed a positive influence (through increase in germination percentage, root growth, shoot growth, fresh weight and dry weight) on the studied rice growth and development under induced drought. Isolate 1 and 6 identified as species of Mycobacterium sp and Bacillus sp respectively through molecular taxonomy. Hence, these two isolates are expected to alleviate drought stress in the rice field for their nature of plant growth promotion under drought stress.
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Song, Yu-Dong, and Hong-Ying Hu. "Isolation and characterization of thermophilic bacteria capable of lysing microbial cells in activated sludge." Water Science and Technology 54, no. 9 (November 1, 2006): 35–43. http://dx.doi.org/10.2166/wst.2006.874.
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To find an efficient biological method to solubilize waste activated sludge (WAS) from the biological wastewater treatment process, several strains of thermophilic bacteria capable of solubilizing WAS were isolated from sewage sludge compost. The culture supernatants of the isolates were able to lyse vegetable bacterial cells and the lytic activity mainly came from the exoenzyme produced by the isolates. The culture supernatants of the different isolates showed different lysis characteristics. The factors affecting bacterial cell lysis were investigated using E. coli as a model bacterium. The E. coli cells were lysed easily at higher temperature (60 °C or 70 °C) while little lytic activity by the supernatants of isolates was observed at lower temperature (50 °C). The level of pH also had great influence on the lysis of E. coli cells. The E. coli cells in the early stationary growth phase were easier to lyse than those in the late stationary growth phase or death phase.
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Omran, Arthur, Ronald Baker, and Charles Coughlin. "Differential Bacteriostatic Effects of Sucralose on Various Species of Environmental Bacteria." ISRN Toxicology 2013 (September 30, 2013): 1–6. http://dx.doi.org/10.1155/2013/415070.
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Sucralose was developed as a low-cost artificial sweetener that is nonmetabolizable and can withstand changes in pH and temperature. It is not degraded by the wastewater treatment process and thus has been found in waste water, estuaries, rivers and the Gulf Stream. Since the molecule can withstand heat, acidification, and microbial degradation, it is accumulating in the environment. The highest concentration of environmental sucralose detected to date is 300 ng/L. Our lab has isolated six bacterial species from areas that have been exposed to sucralose. We then cultured these isolates in the presence of sucralose looking for potential sucralose metabolism or growth acceleration. Instead we found something very interesting, bacteriostatic effects exhibited on all six isolates. This inhibition was directly proportional to the concentration of sucralose exposure. The efficiency of the growth inhibition seemed to be species specific, with various concentrations inhibiting each organism differently.
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Khan, M. A., H. Satoh, T. Mino, H. Katayama, F. Kurisu, and T. Matsuo. "Bacteriophage-host interaction in the enhanced biological phosphate removing activated sludge system." Water Science and Technology 46, no. 1-2 (July 1, 2002): 39–43. http://dx.doi.org/10.2166/wst.2002.0453.
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Bacteriophages were isolated from a laboratory scale enhanced biological phosphate removing (EBPR) activated sludge process, and their host range was examined. Bacterial isolates to host the bacteriophages were isolated from the EBPR activated sludge process. Bacteriophages were eluted from the EBPR activated sludge, enriched by incubation with the bacterial isolates, and then tested for plaque formation on each of the bacterial isolates. Out of 12 bacterial isolates isolated, 4 supported plaque formation. Four bacteriophages were obtained from the plaques. The host range test was conducted with the combination of the bacteriophage isolates and the bacterial isolates. Three of the bacteriophages were found to form plaques on more than one host, and one of them formed plaques on both Gram +ve and Gram −ve bacterial isolates. Two of the four bacteriophages failed to form plaques on their original bacterial host, indicating the existence of mutation on either both or one of the host and the bacteriophage. This study strongly suggests that bacteriophages are an active part of the activated sludge microbial ecosystem, having very complex interaction with their host bacteria.
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Hamidović, Saud, Nikolina Vukelić, Teofil Gavrić, Jelena Jovičić-Petrović, Igor Kljujev, Vera Karličić, and Blažo Lalević. "The effects of the "Stomp" herbicide application on the microbial prevalence in the soil." Zemljiste i biljka 71, no. 1 (2022): 15–23. http://dx.doi.org/10.5937/zembilj2201015h.
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Agricultural production has benefited a lot from herbicides; however, the use of herbicides caused many environmental problems. Herbicide application can affect the biodiversity of an ecosystem by killing non-target organisms. Microorganisms in the soil are important factors for plant growth; they represent the biological factor of soil fertility. Herbicides can have a beneficial effect on the development of some microorganisms and a negative on others, leading to depletion of microbial diversity in soil. The objective of this work is to determine microbial activity in the soil and to isolate herbicide-resistant bacteria after the use of the "Stomp" herbicide. Agar plate method was used for the determination of microbial prevalence in the soil. The results showed an increase in the total number of bacteria, ammonifiers, fungi, and actinomycetes. Nine isolates, mostly Gram-positive spore-forming rods, showed an ability to grow in the mineral salt medium with different concentrations of "Stomp" herbicide. Isolates G1/1 and G1/2, showed high level of tolerance at the initial pendimethalin concentration of 25 mg/l. Those isolates have the potential to be used to decontaminate herbicide affected ecosystems.
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Hassan Ali, Nafisa, Amber Farooqui, Adnan Khan, Ameera Yahya Khan, and Shahana Urooj Kazmi. "Microbial contamination of raw meat and its environment in retail shops in Karachi, Pakistan." Journal of Infection in Developing Countries 4, no. 06 (May 4, 2010): 382–88. http://dx.doi.org/10.3855/jidc.599.
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Background: This study was conducted to examine the frequency of contamination in retail meat available in Karachi, Pakistan. Methodology: Raw meat samples (250) and surface swabs (90) from meat processing equipment and the surrounding environment were analyzed for microbiological contamination. Results: Out of 340 samples, 84% were found to be contaminated with bacterial species, including Klebsiella, Enterobacter, Staphylococcus aureus and Bacillus subtilis. A total of 550 (66%) of the bacterial isolates were potential pathogens. Of these, 342 and 208 isolates were from meat and environmental samples respectively. Food-borne pathogens isolated from meat samples included Escherichia coli O157:H7, Listeria, Salmonella Enteritidis and Shigella species whereas environmental samples yielded Staphylococcus aureus and Shigella species. Four strains of Brucella species were also isolated from meat samples. Total aerobic counts ranged between 108 -1010 CFU/g or cm2. Resistance to a wide range of antibiotics was observed. Resistance rates to ampicillin, amoxicillin, novobiocin and cefaclor were from 62 to 75% in general. Thirty-three percent of Salmonella isolates were resistant to ampicillin. No quinolone resistance was observed. Biofilm formation was observed among 88 (16%) pathogenic bacteria including E. coli, Klebsiella, Enterobacter species and Staphylococcus aureus. Conclusions: Food-borne pathogens found in retail shops could be sources for horizontal contamination of meat. Our data confirm the circulation of antibiotic resistant and biofilm forming pathogens in raw meat and its environment in retail shops in Pakistan, which could play a role in the spread of antimicrobial resistance amongst food-borne bacteria.
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Duran, Metin, Deniz Yurtsever, and Timur Dunaev. "Choice of indicator organism and library size considerations for phenotypic microbial source tracking by FAME profiling." Water Science and Technology 60, no. 10 (November 1, 2009): 2659–68. http://dx.doi.org/10.2166/wst.2009.656.
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The primary objective of this study was to investigate the effects of choice of the indicator organisms on the accuracy of classifying the fatty acid methyl ester (FAME) profiles of the known-source library isolates. First, a known-source library containing the FAME profiles of Enterococcus isolates cultured from six different possible sources of microbial pollution was developed. A total of 511 Enterococcus isolates were profiled: 120 isolates from sewage samples representing humans; 69 from dairy and cattle cow; 74 from chicken; 76 from swine; 94 from deer; and 78 from waterfowl. Classification of known-source Enterococcus isolates into their respective host categories resulted with a 66% average rate of correct classification (ARCC) in a six-way discriminant analysis (DA). The ARCC increased to 75% when the individual hosts were pooled into larger categories of human, livestock, and wildlife. The accuracy was 80% when isolates of human origin were discriminated against those of non-human origins. Recently, several studies reported the ARCCs for various classification schemes associated with total coliform (TC), fecal coliform (FC), and Escherichia coli of the known-source isolates. When the accuracy of classification of Enterococcus isolates was compared to those reported for TC, FC, and E. coli isolates, the lowest ARCCs were associated with classification of E. coli isolates, the only species level indicator organism among the four compared. It was found that the degree of discrimination increases as the indicator becomes more inclusive of bacteria from different genus. In addition, random cluster formation analysis indicates that known-source libraries with isolate numbers between 300 and 500 might be sufficient for MST by FAME.
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Chicca, Ilaria, Simone Becarelli, Giacomo Bernabei, Giovanna Siracusa, and Simona Di Gregorio. "Innovative Culturomic Approaches and Predictive Functional Metagenomic Analysis: The Isolation of Hydrocarbonoclastic Bacteria with Plant Growth Promoting Capacity." Water 14, no. 2 (January 6, 2022): 142. http://dx.doi.org/10.3390/w14020142.
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Innovative culturomic approaches were adopted to isolate hydrocarbonoclastic bacteria capable of degrading diesel oil, bitumen and a selection of polycyclic aromatic hydrocarbons (PAH), e.g., pyrene, anthracene, and dibenzothiophene, from a soil historically contaminated by total petroleum hydrocarbons (TPH) (10,347 ± 98 mg TPH/kg). The culturomic approach focussed on the isolation of saprophytic microorganisms and specialist bacteria utilising the contaminants as sole carbon sources. Bacterial isolates belonging to Pseudomonas, Arthrobacter, Achromobacter, Bacillus, Lysinibacillus, Microbacterium sps. were isolated for their capacity to utilise diesel oil, bitumen, pyrene, anthracene, dibenzothiphene, and their mixture as sole carbon sources. Pseudomonas, Arthrobacter, Achromobacter and Microbacterium sps. showed plant growth promoting activity, producing indole-3-acetic acid and expressing 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity. In parallel to the culturomic approach, in the microbial community of interest, bacterial community metabarcoding and predictive functional metagenomic analysis were adopted to confirm the potentiality of the isolates in terms of their functional representativeness. The combination of isolation and molecular approaches for the characterisation of a TPH contaminated soil microbial community is proposed as an instrument for the construction of an artificial hydrocarbonoclastic microbiota for environmental restoration.
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O Elufisan, Temidayo, Isabel Cristina Rodriguez-Luna, Omotayo O Oyedara, Alejandro Sanchez-Varela, Virgilio Bocanegra García, Busayo O Oluyide, Samantha Flores-Treviño, Miguel Angel Villalobos López, and Xianwu Guo. "Antimicrobial susceptibility pattern of Stenotrophomonas species isolated from Mexico." African Health Sciences 20, no. 1 (April 20, 2020): 168–81. http://dx.doi.org/10.4314/ahs.v20i1.22.
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Background: Stenotrophomonas species are multi-resistant bacteria with ability to cause opportunistic infections.
Objective: We isolated 45 Stenotrophomonas species from soil, sewage and the clinic with the aim of investigating their susceptibility to commonly used antimicrobial agents.
Methodology: The identities of isolates were confirmed with 16S rRNA gene sequence and MALDI-TOF analysis. Anti-mi- crobial resistance, biofilm production and clonal diversity were also evaluated. The minimum inhibitory concentration technique as described by Clinical & Laboratory Standards Institute: CLSI Guidelines (CLSI) was employed for the evaluation of isolate susceptibility to antibiotics.
Result: Forty-five Stenotrophomonas species which include 36 environmental strains and 9 clinical strains of S. maltophilia were considered in this study. 32 (88.9 %) environmental strains were identified to be S. maltophilia, 2 (5.6 %) were Stenotrophomonas nitritireducens, and 2 (5.6 %) cluster as Stenotrophomonas spp. Stenotrophomonas isolates were resistant to at least six of the antibiotics tested, including Trimethoprim/Sulfamethoxazole (SXT).
Conclusion: Environmental isolates from this study were resistant to SXT which is commonly used for the treatment of S. maltophilia infections. This informs the need for good public hygiene as the environment could be a reservoir of multi-resistant bacteria. It also buttresses the importance of surveillance study in the management of bacterial resistance.
Keywords: Stenotrophomonas; environmental; biochemical characterization; clonal diversity; anti-microbial susceptibility.
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Njoku, Kelechi L., Eme O. Ude, Temitope O. Jegede, Omotoyosi Z. Adeyanju, and Patricia O. Iheme. "Characterization of hydrocarbon degrading microorganisms from Glycine max and Zea mays phytoremediated crude oil contaminated soil." Environmental Analysis Health and Toxicology 37, no. 2 (April 11, 2022): e2022008. http://dx.doi.org/10.5620/eaht.2022008.
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Microbe-plant partnership in phytoremediation involves a synergistic interaction that leads to degradation of contaminants. The identification and characterization of these microorganisms is fundamental in environmental management. This study is aimed at investigating the influence of Glycine max and Zea mays on microbial make-up and differentiation of soil bacterial and fungal isolates in crude oil contaminated soil. We employed conventional technique of microbial isolation and gene sequencing to evaluate the microbial composition in crude oil contaminated soil. The microorganisms were isolated from crude oil contaminated soil (0%, 4%, 8%) and were identified using 16S rRNA gene (for bacteria) and Internal Transcribed Spacer (ITS) gene (for fungi). We observed a change in the microbial cell density with respect to treatment conditions implying a shift in microbial dynamics to total hydrocarbon utilizing bacteria as the dominant microbes. The sequence data revealed five bacteria strain; Klebsiella aerogenes strain 77, Klebsiella aerogenes strain UISO178, Salmonella enterica strain ABUH7, Klebsiella aerogenes strain M242 and Enterobacter sp. NCCP-607 and three fungi strains; Galactomyces geotrichum strain CBS, Aspergillus niger strain YMCHA73 and Trichoderma virens isolate A701. Annotation analysis using FGENESB and gene scan revealed proteins involved in various metabolic processes and hydrocarbon utilization. GHOSTKOLA output revealed several genetic elements and pathways such as DnaA, PYG, mrcA, environmental, cellular and genetic information processing and degradation enhancers. Our findings show that G. max and Z. mays in association with bacteria can enhance ecosystem restoration of crude oil contaminated soil.
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Anandham, Rangasamy, and Tongmin Sa. "Editorial for Special Issue “Environmental Factors Shaping the Soil Microbiome”." Applied Sciences 11, no. 21 (November 5, 2021): 10387. http://dx.doi.org/10.3390/app112110387.
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Soil is a complex system consisting of various abiotic and biotic factors interacting among themselves in a particular time period. These biotic factors are particularly affected by a large number of disturbances or perturbations occurring in the micro-niches. Soil microbiome is the paramount biotic factor responsible for nutrient cycling that in turn determines soil health and quality. However, there are limitations in studying soil systems as there are a number of unknown boxes that need to be checked before understanding their full-fledged contribution to the environment. The microbial diversity in the soil can be affected by salinity, contaminant, fertilization, nutrient accumulation, and cultivation practices. Additionally, plants can also benefit from these changes in microbial community composition, and novel microbial isolates can be used for enhancing their growth under various stress conditions. Collectively, this Special Issue includes various studies that determine key abiotic and biotic factors that can result in changes in microbial community composition in the soil system. These studies are carried out in specified environmental niches rather than microcosms, which provides a broader context in which to understand microbial dynamics.
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MYŠKOVÁ, PETRA, and RENÁTA KARPÍŠKOVÁ. "Unusual Occurrence of Salmonella Mikawasima in 2012–2013 in the Czech Republic: Part of a Multistate Outbreak?" Polish Journal of Microbiology 63, no. 3 (2014): 355–57. http://dx.doi.org/10.33073/pjm-2014-047.
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An increased number of cases of salmonellosis caused by the rare serotype Mikawasima was noted in the years 2012 and 2013 in the Czech Republic. A potential on-going outbreak caused by this serotype in European countries has also been reported. Altogether 14 human and 1 environmental isolates from the year 2012 and 11 human isolates from the year 2013 from different locations of the Czech Republic were sent to our laboratory for typing. Macrorestriction analysis together with antimicrobial susceptibility testing and PCR for ESBL and plasmid-mediated quinolone resistance detection were performed to compare our isolates. Twenty-one isolates created two very similar clusters and 5 isolates had different profiles. Twenty-five isolates were fully susceptible to all agents used. One isolate showed resistance to 12 microbial agents and possessed blaTEM, blaSHV, blaOXA, blaCTX-M and qnrB genes.
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Carrero-Col�n, Militza, Cindy H. Nakatsu, and Allan Konopka. "Effect of Nutrient Periodicity on Microbial Community Dynamics." Applied and Environmental Microbiology 72, no. 5 (May 2006): 3175–83. http://dx.doi.org/10.1128/aem.72.5.3175-3183.2006.
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ABSTRACT When microbes are subjected to temporal changes in nutrient availability, growth rate and substrate affinity can contribute to competitive fitness and thereby affect microbial community structure. This hypothesis was tested using planktonic bacterial communities exposed to nutrient additions at 1-, 3-, 7-, or 14-day intervals. Growth rates after nutrient addition were inversely proportional to the pulse interval and declined from 0.5 h−1 to 0.15 h−1 as the pulse interval increased from 1 to 14 days. The dynamics of community structure were monitored by 16S rRNA gene PCR-denaturing gradient gel electrophoresis. At pulse intervals of more than 1 day, the community composition continued to change over 130 days. Although replicate systems exposed to the same pulse interval were physiologically similar, their community compositions could exhibit as much dissimilarity (Dice similarity coefficients of <0.5) as did systems operated at different intervals. Bacteria were cultivated from the systems to determine if the physiological characteristics of individual members were consistent with the measured performance of the systems. The isolates fell into three bacterial divisions, Bacteroidetes, Proteobacteria, and Actinobacteria. In agreement with community results, bacteria isolated from systems pulsed every day with nutrients had higher growth rates and ectoaminopeptidase specific activities than isolates from systems pulsed every 14 days. However, the latter isolates did not survive starvation longer than those provided with nutrients every day. The present study demonstrates the dynamic nature of microbial communities exposed to even simple and regular environmental discontinuities when a substantial pool of species that can catabolize the limiting substrate is present.
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Manikandan, Muthu, Sechul Chun, Zakayo Kazibwe, Judy Gopal, Udai Bhan Singh, and Jae-Wook Oh. "Phenomenal Bombardment of Antibiotic in Poultry: Contemplating the Environmental Repercussions." International Journal of Environmental Research and Public Health 17, no. 14 (July 14, 2020): 5053. http://dx.doi.org/10.3390/ijerph17145053.
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Antibiotics have constantly been added at an unprecedented rate in order to enhance poultry meat production. Such antibiotics impose a negative impact on human health directly through meat and egg consumption. On the other hand, they also affect humans indirectly by affecting the normal key microbial processes in the agricultural environments, when used as poultry compost. For many years, farmers have been turning poultry litter into compost for agricultural use. Very few studies have addressed the fate of the unmetabolized antibiotic residues in poultry litter that could potentially affect microbial communities when used as poultry compost. We have also questioned the fate of residual antibiotic in poultry waste which may create possible negative environmental pressure on microbial communities that are involved in microbial mediated poultry litter composting processes. The incorporation of antibiotic degrading environmental isolates in poultry litter at the initial stage of composting in order to accelerate the process is addressed in this review as a future perspective.
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Wei, Lei, Rebecca J. Rubenstein, Kathleen M. Hanlon, Heidi Wade, Celeste N. Peterson, and Vanja Klepac-Ceraj. "Cutting wedge: bacterial community diversity and structure associated with the cheese rind and curd of seven natural rind cheeses." Fine Focus 3, no. 1 (March 1, 2017): 09–31. http://dx.doi.org/10.33043/ff.3.1.09-31.
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The microorganisms that inhabit cheese contribute greatly to the flavor and development of the final product. While the rind and curd microbiota have been characterized separately, there is limited information on how the structure and function of microbial communities in rinds and curds vary within and amongst cheeses. To better understand the differences in community structure and function between communities of cheese rinds and curds, we combined culture-based methods with culture-independent community profiling of curds and rinds. Rinds contained greater taxonomic diversity than curds. Lactobacillales dominated curd communities while members from the order Actinomycetales were found in high abundance in rind communities. Communities varied more between rinds and curds than among cheeses produced from different milk types. To better understand microbial community functions, we cultured and assayed isolates for antibiotic susceptibility and carbon source utilization. Among European and U.S. cheeses, 70% of all susceptible isolates were cultured from U.S. cheeses. Overall, our study explored the differences within and between rind and curd microbial communities of natural rind cheeses, provided insights into the environmental factors that shape microbial communities, and demonstrated that at the community and isolate level the cheese microbiome was diverse and metabolically complex.
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Lauer, Antje, Joe Baal, Susan Mendes, Kayla Casimiro, Alyce Passaglia, Alex Valenzuela, and Gerry Guibert. "Valley Fever on the Rise—Searching for Microbial Antagonists to the Fungal Pathogen Coccidioides immitis." Microorganisms 7, no. 2 (January 24, 2019): 31. http://dx.doi.org/10.3390/microorganisms7020031.
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The incidence of coccidioidomycosis, also known as Valley Fever, is increasing in the Southwestern United States and Mexico. Despite considerable efforts, a vaccine to protect humans from this disease is not forthcoming. The aim of this project was to isolate and phylogenetically compare bacterial species that could serve as biocontrol candidates to suppress the growth of Coccidioides immitis, the causative agent of coccidioidomycosis, in eroded soils or in areas close to human settlements that are being developed. Soil erosion in Coccidioides endemic areas is leading to substantial emissions of fugitive dust that can contain arthroconidia of the pathogen and thus it is becoming a health hazard. Natural microbial antagonists to C. immitis, that are adapted to arid desert soils could be used for biocontrol attempts to suppress the growth of the pathogen in situ to reduce the risk for humans and animals of contracting coccidioidomycosis. Bacteria were isolated from soil samples obtained near Bakersfield, California. Subsequently, pairwise challenge assays with bacterial pure cultures were initially performed against Uncinocarpus reesii, a non-pathogenic relative of C. immitis on media plates. Bacterial isolates that exhibited strongly antifungal properties were then re-challenged against C. immitis. Strongly anti-C. immitis bacterial isolates related to Bacillus subtilis and Streptomyces spp. were isolated, and their antifungal spectrum was investigated using a selection of environmental fungi.
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Wyatt, Morgan A., Jonghyun Lee, Yasodha Ahilan, and Nathan A. Magarvey. "Bioinformatic evaluation of the secondary metabolism of antistaphylococcal environmental bacterial isolates." Canadian Journal of Microbiology 59, no. 7 (July 2013): 465–71. http://dx.doi.org/10.1139/cjm-2013-0016.
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The increasing occurrence of drug-resistant Staphylococcus aureus is exacerbated with a declining rate of antibiotic discovery, particularly those with new mechanisms of action. The decline in antibiotic discovery from traditional sources, such as soil actinobacteria, necessitates examination of lesser studied microbes. Here, we present a strategy to select for organisms that may have a propensity to result in new antistaphylococcal agents by using S. aureus as a bait organism, and selecting organisms that have a natural lytic activity towards it. We have isolated over 80 environmental isolates and typed these organisms using 16S rDNA sequence comparison and deployed bioinformatics to assess the secondary metabolic potential of the isolated antistaphylococcal bacteria using genomic sequences. Bioinformatic analysis highlights the enriched and unique suite of potential antibiotic polyketides and nonribosomal peptides and lantibiotic gene clusters from these organisms. Profiling organic microbial extracts further showed that many of the organisms from the 10 staphylolytic genera secrete agents with antistaphylococcal activity and may serve as new sources for future antistaphylococcal drug discovery.
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Yasmeen, Roheela, Hifsa Ali Muhammad, Bushra Nisar Khan Bushra Nisar Khan, Syeda Shazia Bokhari, Uzma Rafi, and Aisha Qurashi. "Microbial Diversity in Gut of Cattle Egrets (Bubulcus Ibis) On Exposure to Different Environment." Lahore Garrison University Journal of Life Sciences 3, no. 1 (April 22, 2020): 23–30. http://dx.doi.org/10.54692/lgujls.2019.030152.
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Cattle egrets (Bubulcus ibis) normally nest near water and normally feed in grass or wetlands. But now, they are changing their habitat and are also seen feeding on crop fields and garbage dumping sites. The study was conducted to assess gut flora of locally matured cattle egret exposed to different environments. The sampling was carried out in winter season of 2017 at two sites of Lahore, Havalian Karbath (rural, site 1) and Mehmood Booti (urban, site 2). The microbial analysis was carried out to find out diversity in bacterial fauna present in gut (stomach and intestine) of cattle egrets. The total of eight bacterial isolates was collected from stomach and intestine of site 1 and site 2. The characteristics study of bacterial isolates was based on morphological and biochemical tests. The bacterial isolates from site 1 were noticed as Bacillus spp. and Staphylococcus spp. However, from site 2, Staphylococcus spp., Listeria spp. and Streptococcus spp. were isolated. It was concluded on morphological characterization of isolates that diverse morphology of bacteria associated with gut flora of cattle egret on exposure to different environmental sites. However, a detailed study at species level is required to identify disease causing ability of microbes.
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Sharma, Priya, and Srikanth Mutnuri. "Nutrient recovery and microbial diversity in human urine fed microbial fuel cell." Water Science and Technology 79, no. 4 (February 15, 2019): 718–30. http://dx.doi.org/10.2166/wst.2019.089.
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Abstract Presence of urine in municipal wastewater is a major problem faced by wastewater treatment plants. The adverse effects are noticeable as crystallization in equipment and pipelines due to high concentration of nitrogen and phosphorus. Therefore, improved technologies are required that can treat urine separately at the source of their origin and then discharge it in the main wastewater stream. In this study, the performance of the microbial fuel cell (MFC) was evaluated with mixed consortia and isolated pure cultures (Firmicutes and Proteobacter species) from biofilm for electricity generation and nutrient recovery. Microbes utilize less than 10% of total phosphorus for their growth, while 90% is recovered as struvite. The amount of struvite recovered was similar for pure and mixed culture (12 ± 5 g/L). The microbial characterization also shows that not all the biofilm-forming bacterial isolates are very much efficient in power generation and, hence, they can be further exploited to study their individual role in operating MFC. The different organic loading rates experiment shows that the performance of MFC in terms of power generation is the same for undiluted and five times diluted urine while the recovery of nutrients is better with undiluted urine, implying its direct use of urine in operating fuel cell.
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Novák, Jaroslav, Věra Vlasáková, Richard Tykva, and Tomáš Ruml. "Degradation of juvenile hormone analog by soil microbial isolates." Chemosphere 52, no. 1 (July 2003): 151–59. http://dx.doi.org/10.1016/s0045-6535(03)00221-2.
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Connell, Katherine R., Phillip S. Miller, Thomas E. Burkey, J. Dustin Loy, and Samodha C. Fernando. "PSVI-13 Identifying Probiotic Bacteria to Reduce Pathogen Colonization in Nursery Pigs." Journal of Animal Science 100, Supplement_2 (April 12, 2022): 160. http://dx.doi.org/10.1093/jas/skac064.273.
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Abstract Weaning stress and the negative health effects that occur with it cause serious concerns for pork producers. The abrupt environmental and dietary transitions that occur at weaning often take place before the gut microbiome is stabilized in the piglet. This leaves weanling piglets vulnerable to gut dysbiosis and increases susceptibility to enteric pathogens. The infections by opportunistic pathogens can be prevented with antibiotics, but due to growing concerns surrounding antimicrobial resistance in bacterial populations, direct-fed microbial (DFM) formulations have emerged as an alternative prevention method. In the current study, we isolated Lactobacillus spp. and Bifidobacterium spp. from fecal samples collected from neonatal pigs and sows that are capable of inhibiting colonization of Salmonella spp. and Escherichia coli isolated from sick pigs. Diluted fecal samples were plated on Bifidus selective medium (BSM) and deMan, Rogosa Sharpe (MRS) medium to isolate Bifidobacterium and Lactobacillus, respectively. Bacterial isolates were screened against Salmonella and E. coli isolates of porcine origin using a medium consisting of 50% MRS and 50% brain, heart, lung infusion (BHI) using disk diffusion assays. The resulting isolates that demonstrated the greaest degree of pathogen inhibition were characterized using 16s rRNA sequencing. Sequence analysis identified the top isolates as L. mucosae, L. reuteri, and B. thermacidophilum subsp. porcinum. Currently, genome sequencing of the selected isolates is underway to identify the mechanisms of inhibition.
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Ojo-Omoniyi OA, Akinnola OO, Adeduro MR, and Mmadu CP. "Microbiological evaluation of the environmental quality of a pharmaceutical plant in Lagos, Southwest Nigeria." World Journal of Biological and Pharmaceutical Research 2, no. 2 (May 30, 2022): 063–69. http://dx.doi.org/10.53346/wjbpr.2022.2.2.0031.
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The evaluation of predominant microorganisms distributed in the air of the critical rooms in the production plant of a pharmaceutical company in Agege Local Government area, Lagos-Nigeria was investigated using settle- plate method. A total of seven critical rooms in the production facility that is, Dispensary, Granulation, Blending, Blistering, Tableting, Syrup, and Syrup filling rooms were sampled respectively under aseptic conditions. These samples were processed in duplicates on Sabouraud Dextrose Agar (SDA) and Tryptone Soya Agar (TSA) and incubated at 25ºC and 37 ºC respectively. Thereafter, microorganisms were isolated and identified using standard and conventional methods. The data obtained were analyzed to find the microbial distributions in the environment of the pharmaceutical facility. Eight bacterial species were isolated from different locations in the pharmaceutical facility, they were of the following genera; Staphylococcus (12.5%), Micrococcus (50%) and Bacillus (37.5%). Most of the microorganisms found in this study belong to the genus Micrococcus (four species) and three Bacillus species and one Staphylococcus species. Despite the compliance of this company with international standards, the above mentioned microbial species were still found within the facility. Hence, compliance with the international specified standard alone, that is, Good Manufacturing Practice (GMP) does not guarantee sterile pharmaceutical product from the industry. Therefore, other microbial quality assurance procedures must be strictly adhered to in order to have products that comply with international specifications. The microbial isolates from the pharmaceutical facility include: Bacillus subtilis, Bacillus badius, Staphyloccocus aureus, Proteus mirabilis, Microccocus sp. Pseudomonas aeruginosa, Enterobacter aerogenes, Citrobacter sp. Talaromyces sp. Aspergillus tamari.
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Sree, Sudha. "A Study on Isolation and Identification of Exopolysaccharide (EPS) producing Bacteria from Soil." International Journal for Research in Applied Science and Engineering Technology 9, no. 12 (December 31, 2021): 650–71. http://dx.doi.org/10.22214/ijraset.2021.39341.
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Abstract: Polysaccharides are important potent molecules with their structural and compositional complexity which led to wide range of applications in various industries. The exopolysaccharides of microbial origin are released in response to extreme environmental conditions for the purpose of survival. The present study focuses on the isolation of exopolysaccharide producing bacteria from the soil sample and oil contaminated soil sample. Screening for the EPS production by the isolates is determined by the dry weight determination of precipitates of EPS and quantitative estimation of glucose content of EPS by PhenolSulphuric acid method. In the present study, out of 5 bacterial isolates isolated on screening, Lactobacillus sps and Pseudomonas sps. isolates produced the precipitates of EPS whose dry weight was determined to be 0.09g and 0.17g respectively. Further, glucose concentration of EPS was quantitatively determined. The glucose content of Lactobacillus sps. isolate was 0.1125mg/ml and Pseudomonas sps. isolate is 0.2875mg/ml. The EPS producing isolates were further grown in the presence of carbon sources like Glucose, Lactose, Maltose and Sucrose to determine the best utilizable carbon for their growth. The most utilizable carbon source for maximum growth of EPS producing isolates was determined to be sucrose with 2% concentration. All the 5 bacterial isolates were screened for their ability of antibiotic resistance. The EPS producing isolates, Lactobacillus sps, Pseudomonas sps were found to be resistant towards all the antimicrobial agents owing to the presence of EPS protective layer around their cell wall than non-EPS producing isolates. Keywords: Exopolysaccharide, Screening, Carbon sources, Antibiotic resistance.
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Al-Charrakh, Alaa Hani. "Frequency and antimicrobial resistance of bacteria isolated from oral and topical medicaments from Hilla, Iraq." Journal of Infection in Developing Countries 6, no. 06 (March 26, 2012): 489–94. http://dx.doi.org/10.3855/jidc.1817.
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Introduction: The presence of microorganisms in pharmaceuticals is undesirable because they may cause spoilage of the product and may present an infection hazard to the consumers or patients. Methodology: A total of 102 samples of oral and topical non-sterile pharmaceutical products were collected at random from different drug houses and pharmacies in Iraq, to investigate the microbial contamination of these products. Bacterial isolates recovered from these medicaments were subjected to susceptibility testing against various antibiotics by disk diffusion method according to Clinical and Laboratory Standards (CLSI) guidelines. Results: The results revealed that the occurrence of Gram-positive bacteria was in oral and topical medicaments while Gram-negative bacteria were only detected in topical medicaments. More than 58% of Bacillus isolates were resistant to lincomycin and Bacillus mycoides isolates were resistant to beta-lactam antibiotics and trimethoprim-sulfamethoxazole. Staphylococcus spp. showed a relatively high resistance to ampicillin, amoxicillin, penicillin, tetracycline, and trimethoprim-sulfamethoxazole. S. epidermidis had the highest number of multi-resistant isolates. Furthermore, 87.5% of isolated Gram-negative rods showed high resistance to beta-lactam antibiotics and 75% of them were highly resistant to erythromycin. One isolate of Pseudomonas aeruginosa was the most resistant among all Gram-negative rod isolates. Conclusion: The high rate of resistance to antimicrobial agents of bacterial isolates recovered from oral and topical medicaments in this study may indicate a widespread antibiotic resistance among bacteria isolated from different sources, including those of anthropological and environmental origin.
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Senok, Abiola, Ghada Garaween, Adeola Raji, Harish Khubnani, Garwin Kim Sing, and Atef Shibl. "Genetic relatedness of clinical and environmental Acinetobacter baumanii isolates from an intensive care unit outbreak." Journal of Infection in Developing Countries 9, no. 06 (July 4, 2015): 665–69. http://dx.doi.org/10.3855/jidc.6726.
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Introduction: Determination of microbial genetic relatedness is important for improving efficiency of infection control measures during hospital outbreaks. This study aimed to analyze the clonal relationships of clinical and environmental Acinetobacter baumannii strains isolated during an outbreak in the intensive care unit (ICU) of a secondary care hospital in Saudi Arabia. Methodology: Twelve clinical and fourteen environmental A. baumannii isolates identified during an outbreak in February 2013 in the 14-bed adult intensive care unit of a tertiary care hospital in Riyadh, Saudi Arabia, were studied. Bacterial identification and antimicrobial susceptibility testing were carried out using Microscan Walkaway 96 automated system. Determination of clonal diversity was investigated by repetitive-sequence-based polymerase chain reaction (rep-PCR) with the semi-automated DiversiLab system. Results: The majority of the clinical isolates were from endotracheal tube aspirates (n = 9), one from a wound swab and two were from urine and sputum, respectively. Environmental isolates were from bed railings (n = 10) and with one each from curtain, stethoscope, computer mouse and telephone. Isolates were categorized into 6 clusters (Groups 1-6). Most of the isolates were associated with two clusters namely Groups 2 (n = 11) and 3 (n = 9). All isolates were multidrug resistant showing resistance to three or more classes of antibiotics. One clinical strain from Cluster 3 was resistant to colistin (MIC > 4ug/ml). Conclusion: This outbreak was caused by two clonal groups of multidrug resistant A. baumannii. The presence of multiple environmental clones was suggestive of environmental source dissemination via healthcare workers within the ICU.
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Fashola, F. A., O. T. Fadipe, P. N. Nwagala, S. O. Olatope, C. P. Augustine, O. I. Ibidapo, I. C. James, F. B. Aderinwale, F. A. Orji, and A. K. Lawal. "Characterization of Novel Alkaline Protease producing Bacillus subtilis C3a-FIIRO with Potential for Industrial Application." Nigerian Journal of Biotechnology 38, no. 2 (March 3, 2022): 56–66. http://dx.doi.org/10.4314/njb.v38i2.6.
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Microbial alkaline protease is one of the dominant industrial enzymes which function in splitting polypeptides chain of protein into monomers of amino acids and peptides. This study aimed to identify alkaline protease produced by Bacillus sp. Soil samples were aseptically collected from dump sites in FIIRO, Lagos state, Nigeria. The samples were serially diluted, and bacteria were isolated using pour plate method. The resulting isolates were screened and morphologically characterized. The isolate with the highest protease production potential was subjected to biochemical characterization using Analytical Profile Index (API) identification kit system and 16S rRNA sequencing. The selected isolate was used to produce alkaline protease by solid state fermentation using rice bran as a substrate. Out of the 18 bacteria isolated, 11 isolates showed alkaline protease production potential. Isolate C3a-FIIRO was selected for its maximal alkaline protease produced as indicated by a 56 mm zone of clearance. Morphological and biochemical characterization revealed isolate C3a-FIIRO as a member of the genus Bacillus. The 16S rRNA gene sequencing confirmed the isolate as Bacillus subtilis C3a-FIIRO (MW577298) with closest homology to Bacillus subtilis Y17B. The enzyme activity of 6848.171 U/ml ± 0.11 and protein concentration of 152.13 mg/ml ± 0.003 showed that Bacillus subtilis C3a-FIIRO has potential for sustainable alkaline protease production.
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Filho, Natalino Perovano, Ismarley Lage Horta Morais, Lívia Carneiro Fidélis Silva, Claudio Mudadu Silva, João Carlos Teixeira Dias, Cynthia Canedo da Silva, and Sérgio Oliveira de Paula. "Production of extracellular polymeric substances by isolate consortia obtained from mesophilic aerobic granules from the treatment of paper mill effluent." BioResources 14, no. 3 (June 10, 2019): 5845–61. http://dx.doi.org/10.15376/biores.14.3.5845-5861.
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Aerobic granules are large, compact microbial aggregates when compared to flocculent sludge, and they can be used in wastewater treatment. The application of aerobic granular sludge in bioreactors for the treatment of industrial effluents is still considered innovative and has been the subject of several recent studies. In the present study, 19 microbial isolates from mesophilic aerobic granules, obtained from a previous study, were evaluated in co-aggregation tests. The extracellular polymeric substances (EPS) produced, such as carbohydrates, proteins, and humic acids, were determined. The aim was to evaluate the relationship between the amount of EPS produced and the contribution of each isolate in the granulation process. The results of EPS production were used to analyze the polysaccharide / protein (PS / PN) ratio. The consortia with an absence of isolates 4, 8, 11, 14, 19, and 25 presented a PS / PN ratio <0.5. These isolates, identified as belonging to the genera Staphylococcus, Agrobacterium, Enterobacter, and Rhodococcus, were considered effective for the production and stability of the mesophilic aerobic granules.
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Bhattacharjee, Arghyadeep, Rajarshi Chaudhuri, Priyanshu Pandey, and Arup Kumar Mitra. "CORRIGENDUM: BIOREMEDIATION OF CHROMIUM (VI) BY A MICROBIAL CONSORTIUM ISOLATED FROM TANNERY EFFLUENTS AND THEIR POTENTIAL INDUSTRIAL APPLICATION." Journal of Environmental Engineering and Landscape Management 30, no. 1 (May 16, 2022): 234. http://dx.doi.org/10.3846/jeelm.2022.16521.
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Arghyadeep Bhattacharjee, Rajarshi Chaudhuri, Priyanshu Pandey, Arup Kumar Mitra, authors of the article “Bioremediation of chromium (VI) by a microbial consortium isolated from tannery effluents and their potential industrial application”, published in Journal of Environmental Engineering and Landscape Management, 29(4), 418–429, https://doi.org/10.3846/jeelm.2021.15762 inform that 423 p. is a minor misinformation in the legend of Figure 4: Figure 4. Observation of Keratinase activity of the isolates. Graphical representation showing the amount of keratin activity by the microorganisms which were determined by the concentration of the vanillin degraded per ml of the crude enzyme. Y-axis indicates the enzymatic activity expressed in U/ml and X-axis denotes the test isolates. Data (n = 3) illustrated in the bar diagram as mean +SD. ***p < 0.0001 as determined by One-way ANOVA (IS1 to IS4 represents the isolates; BSA: Bovine Serum Albumin) The correct legend is: Figure 4. Observation of Keratinase activity of the isolates. Graphical representation showing the amount of keratin activity by the microorganisms. Y-axis indicates the enzymatic activity expressed in U/ml and X-axis denotes the test isolates. Data (n = 3) illustrated in the bar diagram as mean +SD. ***p < 0.0001 as determined by One-way ANOVA (IS1 to IS4 represents the isolates) The authors regret the error.
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Tay, S. T. L., H. L. Jiang, and J. H. Tay. "Functional analysis of microbial community in phenol-degrading aerobic granules cultivated in SBR." Water Science and Technology 50, no. 10 (November 1, 2004): 229–34. http://dx.doi.org/10.2166/wst.2004.0651.
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Phenol-degrading aerobic granules were cultivated in a sequencing batch reactor with an influent phenol concentration of 500 mg l−1. Eight strains were isolated from aerobic granules to characterize the functional redundancy of the microbial community in the granules. The specific oxygen utilization kinetics show the eight strains possessed different phenol-degrading activities, with half-saturation constants (Ks) ranging from 0.4 to 70.5 mg phenol l−1. Two isolates belonging to dominant populations expressed differing functions. The first strain was linked to the function of phenol degradation as this strain has the highest phenol-degrading ability among all isolates, while the second strain was linked to the maintenance of the granule structure because of its strong self-flocculation activity. This study could be used to exploit the granule-based system for treating high-strength wastewaters.
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Sharma, Sonia, and Prof Neeraj Wadhwa. "Microbial Retting of Banana Pseudostem." International Journal of Engineering and Advanced Technology 11, no. 1 (October 30, 2021): 162–66. http://dx.doi.org/10.35940/ijeat.a3195.1011121.
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Fibrous wastes correspond to approximately 54.3 wt.-% of a banana plant. The waste weight is mainly of bunches, stems, and leaves. These ligno-cellulosic fibre waste can be designed and tailored to yield value added products which can be exploited by the farmers, exporters and weavers. Pectin (plant cement) and hemicelluloses (22-25%) found in plant cell walls in the plate (middle lamella). These macromolecules have needs to be hydrolyzed faster without affecting the quality of fibre. The chemical and mechanical processes adopted for fibres actually affect color uptake, strength of fibre thus fetching lower price. We report a biological ecofriendly method of retting where pectinases produced by the endophytic microorganisms of banana pseudostem were used to separate the fibre bundles of cellulose.. Endophytes are microorganisms which live in close relationship with living plant tissues in a cooperative relationship delivering a few auxiliary metabolites and proteins with the possibility to hydrolyse a few plant-determined macromolecules of the host. They spend the entire or part of their lifecycle colonizing within sound tissues of the host plants.The endophytic pectinase helps to break down the cell walls and can find commercial application in extraction of fibres.Seven bacterial isolates were screened and isolated in pectinase screening agar medium [PSAM]. Pectinase producing endophytic bacteria is isolated from corm of Amorphophallus paeoniifolius reported by us are Staphylococcus sciuri, Exiguobacterium acetylicum, Exiguobacterium indicum which are good pectinase producers having specific activity of 8.26, 12.61, 6.81 respectively. Treatment of banana pseudostem with these microbes showed 91%, 94%, 96.7% loss in the total weight of stem leaving behind pure cellulose fibres.
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Yetti, Elvi, Ahmad Thontowi, and Yopi Yopi. "Optimization of Substrate and Starter Cell Concentrations for Dibenzothiopene Biodegradation by Indigeneous Marine Bacteria Mauricauda olearia LBF-1-0009, Alcanivorax xenomutants LBF-1-0018, and Stakelama pacifica LBF-1-0031." ANNALES BOGORIENSES 21, no. 2 (February 28, 2018): 38. http://dx.doi.org/10.14203/ab.v21i2.300.
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Dibenzothiophene (DBT) and its derivatives have been widely used as model organic sulfur compounds in petroleum, included their biodegradation process. The abilities of microorganisms to degrade pollutants are significantly influenced by various factors such as microbial species, nutrients and environmental parameters. In this research, we carried out further study to determine optimal condition for DBT biodegradation regarding with substrate and strains cell concentration by several indigenous marine bacteria from Indonesia. These three isolates were belong to Mauricauda olearia, Alcanivorax xenomutants, and Stakelama pacifica, with homology result 99% each. Optimal dibenzothiophene as substrate reached by all isolates is 100 ppm, while cell concentration or microbial numbers that gave highest growth for all isolates is 20 based on conversion of OD600 nm measurement.
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Yetti, Elvi, Ahmad Thontowi, and Yopi Yopi. "Optimization of Substrate and Starter Cell Concentrations for Dibenzothiopene Biodegradation by Indigeneous Marine Bacteria Mauricauda olearia LBF-1-0009, Alcanivorax xenomutants LBF-1-0018, and Stakelama pacifica LBF-1-0031." ANNALES BOGORIENSES 21, no. 2 (December 22, 2017): 38. http://dx.doi.org/10.14203/ann.bogor.2017.v21.n2.38-44.
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Dibenzothiophene (DBT) and its derivatives have been widely used as model organic sulfur compounds in petroleum, included their biodegradation process. The abilities of microorganisms to degrade pollutants are significantly influenced by various factors such as microbial species, nutrients and environmental parameters. In this research, we carried out further study to determine optimal condition for DBT biodegradation regarding with substrate and strains cell concentration by several indigenous marine bacteria from Indonesia. These three isolates were belong to Mauricauda olearia, Alcanivorax xenomutants, and Stakelama pacifica, with homology result 99% each. Optimal dibenzothiophene as substrate reached by all isolates is 100 ppm, while cell concentration or microbial numbers that gave highest growth for all isolates is 20 based on conversion of OD600 nm measurement.
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Hasan, Md Kamrul, Amin Lutful Kabir, Md Abdul Aziz, Adnan Hasan Masud, Sk Md Abu Bakkar, Munim Ahmed, M. Hafizur Rahman, and M. Mahbubur Rahmman. "Spectrum Of Microbial Isolates From Blood Culture In Febrile Neutropenia." Journal of Chittagong Medical College Teachers' Association 24, no. 1 (September 14, 2013): 19–21. http://dx.doi.org/10.3329/jcmcta.v24i1.57744.
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Infection remains an important cause of morbidity and mortality in neutropenic hosts after chemotherapy or due to bone marrow failure. In the face of worldwide changes in the incidence and spectrum of bacteraemia, we evaluated 47 febrile neutropenic patients in the haematology department of BSMMU during the period of October 2009 to October 2010. The overall rate of blood culture positivity was 17% (8/47) which is similar to most of the recent study in the western world, but the bacterial spectrum is different from that in developed world [1,2,3,4] JCMCTA 2013 ; 24 (1): 19-21
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Kalyani, R., N. Arvind, N. Suresh Kumar, Mahendra M. Reddy, and K. Dinesh. "Bacterial Colonization of Intensive Care Unit Environment and Healthcare Workers in A Tertiary Care Hospital in Kolar Region, India." Journal of Pure and Applied Microbiology 15, no. 1 (February 24, 2021): 402–9. http://dx.doi.org/10.22207/jpam.15.1.37.
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Direct shedding of microbes by patients and health care workers results in contamination of Intensive care unit environment. Intensive care unit acquired infections due to microbial contamination is a major concern because the patient’s immunity is already compromised. To determine the rate of bacterial contamination on environmental surfaces of Intensive care unit and health care workers and to determine the antibiogram of the isolates. Air samples and swabs from healthcare workers, their accessories, surrounding environmental surfaces were collected randomly over a period of 2 months in Adult Intensive care units. Bacterial isolates were identified by standard microbiological techniques. Antibiotic sensitivity testing was performed by Kirby Bauer disc diffusion method and data analyzed by Statistical Product and Service Solutions 22 version software. A total of 208 samples were randomly collected over 2 months, of which 56 samples yielded positive bacterial growth. Of 56 growth, 12 isolates were detected from air sampling method and 44 isolates from swabs. Among 44 isolates identified from swabs, 10 were isolated from healthcare workers, 4 from health care worker’s accessories and 30 from environmental surfaces. Six different bacterial isolates were identified, Coagulase Negative Staphylococcus (24) and Micrococcus (15) were the major isolates followed by Non fermenters (6), Staphylococcus aureus(4), Bacillus species(4) and diphtheroids (3) The antimicrobial sensitivity pattern of these bacterial isolates were sensitive to commonly used antibacterial agents. Study results showed Intensive care unit staff and environmental surfaces as probable sources of bacterial contamination. Study highlights the importance of cleaning and disinfection process and educate the health care workers about the possible sources of infections within Intensive care unit.
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Neesa, Lutfun, Nasrin Jahan, Md Abdullah Al Noman Khan, and Mohammad Shahedur Rahman. "Cellulolytic Bacillus May or May Not Produce β -Glucosidase Due to Their Environmental Origin – A Case Study." Journal of Microbiology and Biotechnology Research 7, no. 6 (December 5, 2017): 30. http://dx.doi.org/10.24896/jmbr.2017764.
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Microbial cellulases have been drawing attention worldwide because of their massive capacity to process the most abundant cellulosic biomass into sustainable biofuels and other valuable products. Profitable biomass conversion processes are highly dependent on the use of efficient enzymes for lignocellulose degradation. Among the cellulose degrading enzymes, β-glucosidases are essential for efficient hydrolysis of cellulosic biomass as they relieve the inhibition of the cellobiohydrolases and endoglucanases by reducing cellobiose accumulation. In this study cellulolytic bacteria with potential β-glucosidases activity were isolated and screened from biogas plant effluent and dairy effluent near Jahangirnagar University campus. From initial screening a total of 16 isolates were found to have cellulolytic activity, among them three isolates (B1, B5, D4) were selected based on their superior results. All the three bacterial isolates were identified as B. subtilis (B1), Bacillus amyloliquefaciens (B5) and B. subtilis (D4) respectively based on their morphological, biochemical and molecular characteristics. The β-glucosidases activity of these three potential cellulolytic bacteria was performed by measuring the release of PNP using pNPG as a substrate and interestingly D4 strain was resulted with β-glucosidases negative where B1 strain was found to have efficient for β-glucosidases activity.