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Biologia 2022Aquaculture is a highly productive and fast-growing agricultural sector. The occurrence of epidemic or sporadic disease outbreak is a major limiting factor in this...
Aquaculture is a highly productive and fast-growing agricultural sector. The occurrence of epidemic or sporadic disease outbreak is a major limiting factor in this sector, thus better alternatives are the need of the hour. Use of indigenous probiotics is a promising strategy to control infectious diseases. Thus, the present study was aimed to screen and characterize potent indigenous probiotics from marine fish, towards enhancing sustainable aquaculture production. Totally 347 bacterial isolates were obtained from gastrointestinal tract, out of these, four isolates (KAF121, 124, 135, 136) were confirmed as potent probiotics in terms of biosafety, highly resistant to acidic pH, gastric juice, bile salt, high hydrophobicity to solvents, auto and co-aggregation potential. These four isolates also exhibited virtuous antioxidant activity. Further the isolates, KAF124 and 135 proved their efficiency in growth and survival of fish after challenged againt . The isolates were identified based on their 16S rRNA gene sequence and the data were submitted to Genbank as KAF121 (MH393516) KAF124 (MH393226) KAF135 (MH393230) and KAF136 (MH393230). The results conclude that two isolates, KAF124 and KAF135 are highly safe and potent probiotics which are first time isolated from the marine fish The two strains could be used as better alternatives to antibiotics and other chemical-based drugs to prevent/control infectious diseases in aquaculture.
PubMed: 35034969
DOI: 10.1007/s11756-021-00957-w -
ISRN Biotechnology 2013The bioavailability of organic contaminants to the degrading bacteria is a major limitation to efficient bioremediation of sites contaminated with hydrophobic...
The bioavailability of organic contaminants to the degrading bacteria is a major limitation to efficient bioremediation of sites contaminated with hydrophobic pollutants. Such limitation of bioavailability can be overcome by steady-state biofilm-based reactor. The aim of this study was to examine the effect of such multicellular aggregation by naturally existing oil-degrading bacteria on crude oil degradation. Microorganisms, capable of utilizing crude oil as sole carbon source, were isolated from river, estuary and sea-water samples. Biochemical and 16S rDNA analysis of the best degraders of the three sources was found to belong to the Pseudomonas species. Interestingly, one of the isolates was found to be close to Pseudomonas otitidis family which is not reported yet as a degrader of crude oil. Biodegradation of crude oil was estimated by gas chromatography, and biofilm formation near oil-water interface was quantified by confocal laser scanning microscopy. Biofilm supported batches of the isolated Pseudomonas species were able to degrade crude oil much readily and extensively than the planktonic counterparts. Volumetric and topographic analysis revealed that biofilms formed in presence of crude oil accumulate higher biomass with greater thickness compared to the biofilms produced in presence of glucose as sole carbon source.
PubMed: 25937972
DOI: 10.5402/2013/250749 -
Environmental Science and Pollution... Jan 2023Thiram (tetramethylthiuramdisulfide) or thiram sulphide is a dithiocarbamate group of non-systemic group of fungicide which are applied for seed treatment, control of...
Thiram (tetramethylthiuramdisulfide) or thiram sulphide is a dithiocarbamate group of non-systemic group of fungicide which are applied for seed treatment, control of the crop pests, to repel animals, etc. Moreover, thiram has also been responsible to cause moderate skin sensitivity and eye irritation. Higher exposure to thiram might also lead to developmental damages to newborn and neurotoxic effects to non-target organisms. Advancing to prevent such toxic effects and prevention of soil fertility from thiram and thiram-like chemicals is indispensable. The analytical High-Performance Thin-Layer Chromatography (HPTLC) is a simple, quick and a reliable method was proposed and validated for the detection and quantification of various small molecules for many years. This manuscript represents the solution to use microbes to degrade the thiram present in the soil and for that, HPTLC based method to study thiram degradation by Pseudomonas has been designed. Herein, a HPTLC protocol formalised to reveal the detection and quantification of thiram within the range of 100 to 700 ng/spot on TLC plate. The same concentration was then used for calculating percent microbial degradation of thiram from the culture broth. To perform the microbial degradation of thiram, Pseudomonas otitidis strain TD-8 and Pseudomonas stutzeri strain TD-18 were taken as thiram degrader microbial strain. The efficacy of TD-8 to degrade thiram was identified to be 81 and 99% when grown in presence of thiram for 4 days and 8 days, respectively, while TD-18 strain's efficacy to degrade thiram was found to be 57% and 99% when grown in presence of thiram for 4 days and 8 days, respectively.
Topics: Animals; Thiram; Pesticides; Chromatography, Thin Layer; Fungicides, Industrial; Soil
PubMed: 36048383
DOI: 10.1007/s11356-022-22731-4 -
Pathogens (Basel, Switzerland) Feb 2021causes deadly primary amoebic meningoencephalitis (PAM) in humans. Humans obtain the infection by inhaling water or dust contaminated with amebae into the nostrils,...
causes deadly primary amoebic meningoencephalitis (PAM) in humans. Humans obtain the infection by inhaling water or dust contaminated with amebae into the nostrils, wherefrom the pathogen migrates via the olfactory nerve to cause brain inflammation and necrosis. Current PAM treatment is ineffective and toxic. Seeking new effective and less toxic drugs for the environmental control of the amoeba population to reduce human exposure is logical for the management of infection. On the basis of the concept of competitive exclusion, where environmental microorganisms compete for resources by secreting factors detrimental to other organisms, we tested cell-free culture supernatants (CFSs) of three bacteria isolated from a fresh water canal, i.e., , , and , were tested against . The CFSs inhibited growth and caused morphological changes in . At low dose, trophozoites exposed to pyocyanin were seen to shrink and become rounded, while at high dose, the trophozoites were fragmented. While the precise molecular mechanisms of pyocyanin and products of and that also exert anti- activity await clarification. Our findings suggest that pyocyanin may have a role in the control of amphizoic in the environment.
PubMed: 33535404
DOI: 10.3390/pathogens10020142 -
Canadian Journal of Microbiology Apr 2019An important mechanism for microbial resistance to mercury is its reduction into elemental mercury (facilitated by the merA gene). Thirty-eight microbial isolates from a...
An important mechanism for microbial resistance to mercury is its reduction into elemental mercury (facilitated by the merA gene). Thirty-eight microbial isolates from a variety of wastewater sources in Egypt were collected. Approximately 14 of the 38 isolates exhibited not only a high degree of tolerance to mercury (up to 160 ppm) but also a high degree of resistance to other tested heavy metals (Cu, Co, Ni, and Zn). From these 14, the 10 most resistant isolates were selected for further study and were found to include 9 Gram-negative and 1 Gram-positive bacterial strains. Multi-antibiotic-resistance profiles were detected for 6 out of the 10 selected isolates. All the tested Gram-negative isolates (n = 9) harbored a plasmid-encoded merA gene. The mercury removal effectiveness for the 10 selected isolates ranged between 50% and 99.9%, among which Stenotrophomonas maltophilia ADW10 recorded the highest rate (99.9%; at an initial mercury concentration of 20 ppm). To the best of our knowledge, this is the first study to (i) demonstrate the presence of a multimetal-resistant S. maltophilia bacterium with a high mercury tolerance capacity that would make it a suitable candidate for future bioremediation efforts in heavy-metal-polluted areas in Egypt and (ii) report Pseudomonas otitidis as one of the mercury-resistant bacteria.
Topics: Biodegradation, Environmental; Drug Resistance, Bacterial; Egypt; Genes, Bacterial; Mercury; Metals, Heavy; Microbial Sensitivity Tests; Oxidoreductases; Plasmids; Pseudomonas; Stenotrophomonas maltophilia; Wastewater; Water Microbiology; Water Pollutants, Chemical
PubMed: 30633555
DOI: 10.1139/cjm-2018-0379 -
Biologia Futura Sep 2023To study how biofilm-forming rhizobacteria isolated from mines and dumpsites improved the phytoremediation efficacy of B. juncea in metal-contaminated soil. Out of 91...
Biofilm-forming plant growth-promoting rhizobacterial consortia isolated from mines and dumpsites assist green remediation of toxic metal (Ni and Pb) using Brassica juncea.
To study how biofilm-forming rhizobacteria isolated from mines and dumpsites improved the phytoremediation efficacy of B. juncea in metal-contaminated soil. Out of 91 isolates, six were chosen for research based on their tolerance to metals, and their efficient PGPR properties, and subjected to the design of a consortium. A compatibility study revealed no antagonistic interaction between rhizobacterial-consortiums. The results of the biofilm formation and FEG-SEM studies revealed that a consortium-BC8 formed a strong biofilm on the root surface of B. juncea seedlings. Based on results obtained with the phytoextraction efficiency of B. juncea in consortium-BC8 (SMHMZ46 and SMHMP23), they were identified as Klebsiella variicola and Pseudomonas otitidis, respectively, and submitted to NCBI GenBank with accession numbers MZ145092 and OK560623. This rhizobacteria is the first to be reported as assisting Ni and Pb phytoremediation by employing B. juncea. Soil inoculation with consortium-BC8 increased the amount of soluble Ni and Pb by 13.25-fold and 10.69-fold, respectively, when compared to the control. These consortiums-BC8 significantly increased vegetative growth and metal accumulation in root and shoot with a translocation-factor of 1.58 for Ni and soil to root with a bioconcentration-factor of 1.3 for Pb in B. juncea grown in individual soil contamination with 96.05 mg/kg NiCl and 89.63 mg/kg Pb(NO), which are significantly higher than other consortium treatments and the non-inoculated control. B. juncea amendments with a biofilm-forming consortium-BC8 having TF, BCF, and BAC > 1 for Ni, whereas BCF > 1, TF, and BAC < 1 for Pb, are appropriate for green remediation of Ni and phytostabilization of Pb.
PubMed: 37733193
DOI: 10.1007/s42977-023-00179-y -
International Journal of Environmental... Jan 2021Recently, the application of endophytes in the alleviation of different types of stresses has received considerable attention, but their role in drought stress...
Recently, the application of endophytes in the alleviation of different types of stresses has received considerable attention, but their role in drought stress alleviation and growth promotion in soybean is not well-stated. In this study, twenty bacterial endophytes were isolated from soybean root tissues and screened for plant growth-promoting (PGP) traits, biocontrol potential, and drought stress alleviation. Out of them, 80% showed PGP traits, and 20% showed antagonistic activity against (ITCC 2389), (ITCC 1800), and (ITCC 3467), and only three of them showed drought tolerance up to 15% (-0.3 MPa). Results indicated that drought-tolerant PGP endophytic bacteria enhanced soybean seedling growth under drought stress conditions. Morphological, biochemical, and molecular characterization (16S rRNA) revealed that these three bacterial isolates, AKAD A1-1, AKAD A1-2, and AKAD A1-16, closely resemble (GenBank accession No. MN079048), (MW301101), and sp. (MN079074), respectively. We observed that the soybean seedlings were grown in well-watered and drought-stressed soil showed the adverse effect of drought stress on morphological (stem length, root length, plant fresh and dry weight) as well as on biochemical parameters (a decline of photosynthetic pigments, membrane damage, etc.). However, soybean seedlings inoculated with these endophytes have improved the biomass significantly ( ≤ 0.05) under normal as well as in drought stress conditions over control treatments by influencing several biochemical changes. Among these three endophytes, AKAD A1-16 performed better than AKAD A1-2 and AKAD A1-1, which was further validated by the ability to produce the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase in the following order: AKAD A1-16 > AKAD A1-2 > AKAD A1-1. Scanning electron microscopy images also showed a bacterial presence inside the roots of soybean seedlings. These findings supported the application of bacterial root endophytes as a potential tool to mitigate the effect of drought as well as of fungal diseases on the early seedling growth of soybean.
Topics: Alternaria; Ascomycota; Bacteria; Droughts; Endophytes; Fusarium; Plant Roots; Pseudomonas; RNA, Ribosomal, 16S; Glycine max
PubMed: 33494513
DOI: 10.3390/ijerph18030931 -
Journal of Global Antimicrobial... Mar 2024The contamination of fresh surface waters poses a significant burden on human health and prosperity, especially in marginalized communities with limited resources and...
OBJECTIVES
The contamination of fresh surface waters poses a significant burden on human health and prosperity, especially in marginalized communities with limited resources and inadequate infrastructure. Here, we performed in-depth genomic analyses of multidrug-resistant bacteria (MDR-B) isolated from Al-Oueik river water that is used for irrigation of agricultural fields in a disenfranchised area that also hosts a makeshift Syrian refugee camp.
METHODS
A composite freshwater sample was filtered. Faecal coliforms were counted and extended spectrum cephalosporins and/or ertapenem resistant bacteria were screened. Isolates were identified using MALDI-TOF-MS and analysed using whole-genome sequencing (WGS) to identify the resistome, sequence types, plasmid types, and virulence genes.
RESULTS
Approximately 10 CFU/100 mL of faecal coliforms were detected in the water. Four drug-resistant Gram-negative bacteria were identified, namely Escherichia coli, Klebsiella pneumoniae, Enterobacter hormaechei, and Pseudomonas otitidis. Notably, the E. coli isolate harboured bla and a YRIN-inserted PBP3, representing an emerging public health challenge. The K. pneumoniae isolate carried bla as well as mutations in the gene encoding the OmpK37 porin. Enterobacter hormaechei and P. otitidis harboured bla and bla, respectively.
CONCLUSION
This report provides comprehensive genomic analyses of MDR-B in irrigation water in Lebanon. Our results further support that irrigation water contaminated with faecal material can be a reservoir of important MDR-B, which can spread to adjacent agricultural fields and other water bodies, posing both public health and food safety issues. Therefore, there is an urgent need to implement effective water quality monitoring and management programs to control the proliferation of antibiotic-resistant pathogens in irrigation water in Lebanon.
Topics: Humans; Escherichia coli; Rivers; Enterobacter; Plasmids; Klebsiella pneumoniae; Gram-Negative Bacteria
PubMed: 38154747
DOI: 10.1016/j.jgar.2023.12.016 -
Environmental Pollution (Barking, Essex... Sep 2021The bioaerosols present in indoor air play a major role in the transmission of infectious diseases to humans, therefore concern about their exposure is increased...
The bioaerosols present in indoor air play a major role in the transmission of infectious diseases to humans, therefore concern about their exposure is increased recently. In this regard, the present investigation described the preparation of lemongrass essential oil (LGEO) loaded chitosan and cellulose nanofibers composites (CH/CNF) for controlling the indoor air bioaerosol. The evaluation of the inhibitory effect of the composite system on culturable bacteria of the indoor air was done at different sites (air volume from 30 m to 80 m) and in different size fractions of aerosol (<0.25 μm-2.5 μm). The composite system had high encapsulation efficiency (88-91%) and citrals content. A significant reduction in culturable bacteria of aerosol (from 6.23 log CFUm to 2.33 log CFUm) was observed in presence of cellulose nanofibers and chitosan composites. The bacterial strains such as Staphylococcus sp., Bacillus cereus, Bacillus pseudomycoides sp., Pseudomonas otitidis, and Pseudomonas sp. Cf0-3 in bioaerosols were inhibited dominantly due to the diffusion of aroma molecules in indoor air. The results indicate that the interaction of diffused aroma molecule from the composite system with bacterial strains enhanced the production of ROS, resulting in loss of membrane integrity of bacterial cells. Among different size fractions of aerosol, the composite system was more effective in finer size fractions (<0.25 μm) of aerosol due to the interaction of smaller aroma compounds with bacterial cells. The study revealed that LGEO loaded chitosan and cellulose nanofibers composites could be a good option for controlling the culturable bacteria even in small-sized respirable bioaerosol.
Topics: Aerosols; Air Microbiology; Air Pollution, Indoor; Bacillus; Chitosan; Humans; Oils, Volatile; Plant Oils; Pseudomonas; Terpenes
PubMed: 34049138
DOI: 10.1016/j.envpol.2021.117407 -
Microbiological Research Nov 2020In this study, we have attempted to develop a plant growth promoting rhizobacteria (PGPR) consortia against early-stage diseases in Arachis hypogaea (Groundnut crop)...
In this study, we have attempted to develop a plant growth promoting rhizobacteria (PGPR) consortia against early-stage diseases in Arachis hypogaea (Groundnut crop) plantation of Andhra Pradesh, India. The dominant PGPRs were selected by considering the various plant growth and protection qualities, followed by characterisation and grouping based on compatibility to form a consortium of PGPRs [Group-1 includes EX-1 (Acinetobacter baumannii stain HAMBI 1846); EX-3 (Pseudomonas aeruginosa strain A1K319); EX-5 (Bacillus subterraneus strain CF1.9); KNL-1 (Bacillus subtilis strain JMP-B); CTR-4 (Enterobacter cloacae strain VITKJ1); ANT-4 (Bacillus subtilis strain SBMP4) and Group-2 includes EX-4 (Pseudomonas otitidis strain SLC8); KDP-4 (Pseudomonas aeruginosa strain Kasamber 11); NLR-4 (Bacillus species ADMK68); ANT-6 (Bacillus subtilis subsp. inaquosorum strain KCTC 13429)]. In addition to resistance to early stage pathogens, in both in vitro and pot experiments the PGPR consortium showed significantly higher germination rate and root induction (Aspergillus niger; A. flavus; Fusarium oxysporum) when compared to control and fertilizer treated groups. In addition, Group 2 was more successful in stimulating and protecting plant growth among the two groups of PGPRs developed. The PGPR consortia developed showed multiple plant growth characteristics, including phosphate solubilization, production of HCN and Indole acetic acid along with broad antagonism against the tested phytopathogens.
Topics: Acinetobacter baumannii; Arachis; Aspergillus; Aspergillus niger; Bacillus; Bacillus subtilis; Enterobacter cloacae; Fertilizers; Fusarium; India; Indoleacetic Acids; Pest Control; Plant Development; Plant Diseases; Pseudomonas; Pseudomonas aeruginosa; RNA, Ribosomal, 16S; Seeds; Soil Microbiology
PubMed: 32739583
DOI: 10.1016/j.micres.2020.126562