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1.
Sci Data ; 11(1): 456, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710672

RESUMO

We present metagenomes of 16 samples of water and sediment from two lakes, collected from eutrophic and non-eutrophic areas, including pooled samples enriched with phosphate and nitrate. Additionally, we assembled 167 bacterial metagenome-assembled genomes (MAGs). These MAGs were de-replicated into 83 unique genomes representing different species found in the lakes. All the MAGs exhibited >70% completeness and <10% contamination, with 79 MAGs being classified as 'nearly complete' (completeness >90%), while 54 falling within 80-90% range and 34 between 75-80% complete. The most abundant MAGs identified across all samples were Proteobacteria (n = 80), Firmicutes_A (n = 35), Firmicutes (n = 13), and Bacteriodota (n = 22). Other groups included Desulfobacteria_I (n = 2), Verrucomicrobiota (n = 4), Campylobacterota (n = 4) and Actinobacteriota (n = 6). Importantly, phylogenomic analysis identified that approximately 50.3% of the MAGs could not be classified to known species, suggesting the presence of potentially new and unknown bacteria in these lakes, warranting further in-depth investigation. This study provides valuable new dataset on the diverse and often unique microbial communities living in polluted lakes, useful in developing effective strategies to manage pollution.


Assuntos
Eutrofização , Sedimentos Geológicos , Lagos , Metagenoma , Metagenômica , Lagos/microbiologia , Sedimentos Geológicos/microbiologia , África do Sul , Bactérias/genética , Bactérias/classificação , Filogenia , Microbiologia da Água
2.
Heliyon ; 10(6): e27985, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38533070

RESUMO

In water-stressed regions, treated acid mine drainage (AMD) water for irrigated agriculture is a potential solution to address freshwater scarcity. However, a significant knowledge gap exists on the short and long-term effects of treated AMD water on soil health. This study used high-throughput Illumina sequencing and predictive metagenomic profiling to investigate the impact of untreated AMD (AMD), quicklime- (A1Q and A2Q) and quicklime and fly ash-treated AMD water (AFQ) irrigation on soil bacterial diversity, co-occurrence networks and function. Results showed that untreated AMD water significantly increased soil acidity, electrical conductivity (EC), sulfate (SO42-), and heavy metals (HM), including reduced microbial diversity, disrupted interaction networks, and functional capacity. pH, EC, Cu, and Pb were identified as key environmental factors shaping soil microbial diversity and structure. Predominantly, Pseudomonas, Ralstonia picketti, Methylotenera KB913035, Brevundimonas vesicularis, and Methylobacteriumoryzae, known for their adaptability to acidic conditions and metal resistance, were abundant in AMD soils. However, soils irrigated with treated AMD water exhibited significantly reduced acidity (pH > 6.5), HM and SO42- levels, with an enrichment of a balanced bacterial taxa associated with diverse functions related to soil health and agricultural productivity. These taxa included Sphingomonas, Pseudoxanthomonas, Achromobacter, Microbacterium, Rhodobacter, Clostridium, Massillia, Rhizobium, Paenibacillus, and Hyphomicrobium. Moreover, treated AMD water contributed to higher connectivity and balance within soil bacterial co-occurrence networks compared to untreated AMD water. These results show that quicklime/fly ash treatments can help lessen impacts of AMD water on soil microbiome and health, suggesting its potential for irrigated agriculture in water-scarce regions.

3.
Data Brief ; 52: 109849, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38093854

RESUMO

In water-stressed regions, the use of treated acid mine drainage (AMD) water for irrigated agriculture has been suggested as an alternative to address the shortage of fresh water sources. However, the short and long-term impact of using such (un)treated AMD water on soil health, particularly the microbiome structure and functional capacity, is not known. We present high-throughput amplicon sequence (HTS) datasets of purified microbial metacommunity DNA of soils under Irish potato production irrigated by quicklime and fly ash treated AMD water. The irrigation treatments included quicklime treated AMD water (A1Q and A2Q; n = 16), and quicklime and fly ash-treated AMD water (AFQ; n = 5), untreated AMD water (uAMD; n = 7) and control group using tap water (n = 5). The V1-V3 hypervariable region of the 16S rRNA gene from each sample were sequenced on an Illumina MiSeq to generate these HTS datasets. The raw sequences underwent quality-checking, demultiplexing into FASTQ files, and processing using MOTHUR pipeline (v1.40.0). Th quality reads classified into taxonomic ids (phylum, class, order, family, and genus) using the Naïve Bayesian classifier algorithm against the SILVA database (v132) and were assigned to operational taxonomic units (OTUs) based on the pairwise distance matrix (Euclidean distance matrix). The applicability of the HTS datasets was confirmed by microbial taxa at the phylum level. All HTS datasets are available through the BioSample Submission Portal under the BioProject ID PRJNA974836 (https://www.ncbi.nlm.nih.gov/bioproject/974836).

4.
Data Brief ; 51: 109726, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37965618

RESUMO

The Limpopo province, located in the arid-tropical region in northeastern South Africa, is renowned for its diverse natural wetlands, some of which are currently unprotected. These wetlands play a crucial role in preserving biodiversity, purifying water, controlling floods, and supporting agricultural production for rural communities. Unfortunately, human activities such as agricultural effluents, run-offs, domestic wastewater, and plastics pollution, along with the impacts of climate change, are mounting pressures on these ecosystems. However, there is limited information on the microbial ecology of natural wetlands in this region, considering the changing anthropogenic activities. The data presented represents the first report on the microbial and functional diversity of sediment microbiomes associated with unprotected arid-tropical natural wetlands in South Africa. Metagenomic shotgun sequencing was performed on sediment samples from ten different wetlands using the Illumina NextSeq 2000 platform. Taxonomic profiling of 328,625,930 high-quality sequencing reads using the MetaPhlAn v3.0 pipeline revealed that Bacteria were the most abundant kingdom (54.5 %), followed by Viruses (0.40 %), Archaea (0.01 %), and Eukaryota (0.36 %). Among bacteria, the most prevalent taxa belonged to the phylum Proteobacteria, particularly the classes Gammaproteobacteria and Betaproteobacteria, which accounted for 83 % of bacterial sequences. The Terrabacteria group, consisting of the phyla Firmicutes and Actinobacteria, made up 3 % of the bacterial population. The abundance of these top bacterial taxa varied across different wetland samples, both at the genus and species levels. In addition, hierarchical clustering based on Bray-Curtis dissimilarity distances of fungal, protist, archaea, and virus species showed distinct clustering of sediment samples from different wetlands. Functional annotation of the metagenomes identified 1224-1702 enzyme classes, 84,833-198,397 gene families, and 280-400 pathways across the various wetland sediments. The data provide crucial baseline information on the microbial and functional diversity of sediment communities in arid tropical wetlands. This knowledge will contribute to a better understanding of these unique environments and can aid in their management and conservation efforts in rural South Africa.

5.
Arch Environ Contam Toxicol ; 85(2): 165-180, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37592142

RESUMO

The bioaccumulation of heavy metals (HMs) in marine fish is a growing global concern due to potential human health risks. The study analyzed HM in the muscle tissue, gills, and gut of adult male and female cape horse mackerel and slinger seabream caught in the polluted Durban Basin and pristine Cape Vidal from April 2018 to February 2019. Results revealed interspecific, spatial, and organ-specific variability in HM levels. In the Durban Basin, slinger seabream had bioaccumulation (in mg/kg) of As (2.3 ± 0.2), Cr (2.6 ± 0.2), Ni (2.0 ± 0.1), and Pb (4.1 ± 0.3) while cape horse mackerel had Ni (1.6 ± 0.2), Pb (4.7 ± 0.6), and Zn (52 ± 3.01) exceeding World Health Organization (WHO) regulatory limits. Metal pollution index (MPI) values were also higher in Durban Basin (> 5.13) than Cape Vidal (< 3.32) for both species' muscles. Liver and gills of slinger seabream and gut of cape horse mackerel exhibited higher HM accumulation patterns proportionate to the environmental concentrations, indicating the bioindicative potential of HM pollution by the two species. Risk assessment indicated that both fish species had target hazard quotient > 1 for Cr, and target cancer risk < 10-4 for Pb, implying significant potential non-carcinogenic and carcinogenic health risks associated with fish consumption from the Durban Basin. The study recommends daily consumption limits of 16 g/day for slinger seabream and 14 g/day for cape horse mackerel to ensure health safety. The findings contribute to the understanding of HM pollution in the Durban Basin and provide important information for decision-makers and policymakers in developing effective strategies to mitigate and manage HM contamination in fish populations.


Assuntos
Metais Pesados , Perciformes , Dourada , Adulto , Animais , Humanos , Feminino , Masculino , Bioacumulação , África do Sul , Chumbo , Metais Pesados/toxicidade , Medição de Risco
6.
BMJ Open ; 13(7): e073012, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37407035

RESUMO

INTRODUCTION: An understanding of the mental health awareness programmes among workforces in low/middle-income countries (LMICs) is lacking significantly in literature. Such understanding is crucial for the employers, government agencies and other stakeholders to initiate strategies to promote mental health and well-being at the workplace. OBJECTIVE: The main aim of this study is to conduct a scoping review to systematically map the research on the mental health awareness programmes among workforces in LMICs. METHODS: A comprehensive search strategy for the articles published between 2000 and 2022 will be conducted in MEDLINE, PubMed, EBSCOhost, Wiley Online Library, Cochrane and JSTOR. Various study designs such as randomised control trials, non-randomised control trials, systematic reviews, scoping reviews and observational studies that report evidence on mental health awareness programmes among workforce in LMICs will be identified through specific strategy. Search outcomes will be exported to Endnote and duplication of studies will be removed. From the list of included studies, data such as characteristics of mental health programmes, common outcome measures and domains, and motivations underlying the establishment of existing mental health awareness programmes will be extracted and analysed. ANALYSIS: The search outcomes will be presented in a Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow chart. The characteristics of the research studies on mental health programmes will be outlined using tables. The various outcome domains and outcome measures reported in the studies will be presented in a bubble chart showing different outcome measures categorised and collated under a specific outcome domain. The findings on the motivations and justifications underlying the establishment of mental health awareness programmes will be summarised using a thematic analysis. TRIAL REGISTRATION NUMBER: https://doi.org/10.17605/OSF.IO/WPURK.


Assuntos
Países em Desenvolvimento , Saúde Mental , Humanos , Local de Trabalho , Bem-Estar Psicológico , Projetos de Pesquisa , Recursos Humanos , Revisões Sistemáticas como Assunto , Literatura de Revisão como Assunto
7.
Microbiol Res ; 274: 127425, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37348445

RESUMO

Plastic-enriched sites like landfills have immense potential for discovery of microbial consortia that can efficiently degrade plastics. In this study, we used a combination of culture enrichment, high-throughput PacBio sequencing of 16 S rRNA and the ITS gene, Fourier transform infrared (FTIR), and scanning electron microscopy (SEM) to examine the compositional and diversity perturbations of bacterial and fungal consortia from landfill soils and their impact on low-density polyethylene (LDPE) film biodegradation over a 90-day period. Results showed that enrichment cultures effectively utilized LDPE as a carbon source for cellular growth, resulting in significant weight reduction (22.4% and 55.6%) in the films. SEM analysis revealed marked changes in the micrometric surface characteristics (cracks, fissures, and erosion) and biofilm formation in LDPE films. FTIR analyses suggested structural and functional group modification related to C-H (2831-2943 cm⁻¹), and CH2 (1400 cm⁻¹) stretching, CO and CC (680-950 cm⁻¹) scission, and CO incorporation (3320-3500 cm⁻¹) into the carbon backbone, indicative of LDPE polymer biodegradation. Enrichment cultures had lower diversity and richness of microbial taxa compared to soil samples, with LDPE as a carbon source having a direct influence on the structure and functioning of the microbial consortia. A total of 26 bacterial and 12 fungal OTU exhibiting high relative abundance and significant associations (IndVal > 0.7, q < 0.05) were identified in the enrichment culture. Bacterial taxa such as unclassified Parvibaculum FJ375498, Achromobacter xylosoxidans, unclassified Chitinophagaceae PAC002331, unclassified Paludisphaera and unclassified Comamonas JX898122, and six fungal species (Galactomyces candidus, Trichosporon chiropterorum, Aspergillus fumigatus, Penicillium chalabudae, Talaromyces thailandensis, and Penicillium citreosulfuratum) were identified as the putative LDPE degraders in the enrichment microbial consortium cultures. PICRUSt2 metagenomic functional profiling of taxonomic bacterial taxa abundances in both landfill soil and enrichment microbial consortia also revealed differential enrichment of energy production, stress tolerance, surface attachment and motility pathways, and xenobiotic degrading enzymes important for biofilm formation and hydrolytic/oxidative LDPE biodegradation. The findings shed light on the composition and structural changes in landfill soil microbial consortia during enrichment with LDPE as a carbon source and suggest novel LDPE-degrading bacterial and fungal taxa that could be explored for management of polyethylene pollution.


Assuntos
Polietileno , Solo , Polietileno/química , Polietileno/metabolismo , Bactérias/genética , Bactérias/metabolismo , Análise Multivariada , Plásticos/metabolismo , Biodegradação Ambiental , Instalações de Eliminação de Resíduos , Carbono/metabolismo
8.
Environ Sci Pollut Res Int ; 30(13): 36450-36471, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36543987

RESUMO

In sub-Saharan Africa (SSA), urban rivers/streams have long been subjected to anthropogenic pollution caused by urbanization, resulting in significantly altered chemical and biological properties of surface water and sediments. However, little is known about the diversity and structure of river microbial community composition and pathogens, as well as how they respond to anthropogenic inputs. High-throughput 16S rRNA amplicon sequencing and PICRUSt predictive function profiling were used in this study to conduct a comprehensive analysis of the spatial bacterial distribution and metabolic functions in sediment of two urban streams (Kisat and Auji) flowing through Kisumu City, Kenya. Results revealed that sediment samples from the highly urbanized mid and lower stream catchment zones of both streams had significantly higher levels of total organic carbon (TOC), total nitrogen (TN), total phosphorous (TP) than the less urbanized upper catchment zone, and were severely polluted with toxic heavy metals lead (Pb), cadmium (Cd), and copper (Cu). Differential distribution of Actinobacteria, Proteobacteria, Chloroflexi, and Verrucomicrobia in sediment bacterial composition was detected along stream catchment zones. The polluted mid and lower catchment zones were rich in Actinobacteria and Proteobacteria, as well as a variety of potential pathogenic taxa such as Corynebacterium, Staphylococcus, Cutibacterium, Turicella, Acinetobacter, and Micrococcus, as well as enteric bacteria such as Faecalibacterium, Shewanella, Escherichia, Klebsiella, Enterococcus, Prevotella, Legionella, Vibrio and Salmonella. Furthermore, PICRUSt metabolic inference analysis revealed an increasing enrichment in the sediments of genes associated with carbon and nitrogen metabolism, disease pathogenesis, and virulence. Environmental factors (TOC, Pb, Cd, TN, pH) and geographical distance as significant drivers of sediment bacterial community assembly, with the environmental selection to play a dominant role. In polluted river catchment zone sediment samples, Pb content was the most influential sediment property, followed by TOC and Cd content. Given the predicted increase in urbanization in SSA, further alteration of surface water and sediment microbiome due to urban river pollution is unavoidable, with potential long-term effects on ecosystem function and potential health hazards. As a result, this study provides valuable information for ecological risk assessment and management of urban rivers impacted by diffuse and point source anthropogenic inputs, which is critical for future proactive and sustainable urban waste management, monitoring, and water pollution control in low-income countries.


Assuntos
Metais Pesados , Microbiota , Poluentes Químicos da Água , Metais Pesados/análise , Cádmio/análise , Rios/química , Poluentes Químicos da Água/análise , Lagos , Quênia , RNA Ribossômico 16S , Chumbo/análise , Bactérias , Proteobactérias , Nitrogênio/análise , Água/análise , Sedimentos Geológicos/química , Monitoramento Ambiental , China , Medição de Risco
9.
Pathogens ; 11(4)2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35456107

RESUMO

Deciphering the interactions between ticks and their microbiome is key to revealing new insights on tick biology and pathogen transmission. However, knowledge on tick-borne microbiome diversity and their contribution to drug resistance is scarce in sub-Saharan Africa (SSA), despite endemism of ticks. In this study, high-throughput 16S rRNA amplicon sequencing and PICRUSt predictive function profiling were used to characterize the bacterial community structure and associated antibiotic resistance markers in Amblyomma variegatum, A. hebraeum, and Hyalomma truncatum ticks infesting Nguni cattle (Bos spp.). Twenty-one (seven families and fourteen genera) potentially pathogenic and endosymbiotic bacterial taxa were differentially enriched in two tick genera. In H. truncatum ticks, a higher abundance of Corynebacterium (35.6%), Porphyromonas (14.4%), Anaerococcus (11.1%), Trueperella (3.7%), and Helcococcus (4.7%) was detected. However, Rickettsia (38.6%), Escherichia (7%), and Coxiellaceae (2%) were the major differentially abundant taxa in A. variegatum and A. hebraeum. Further, an abundance of 50 distinct antibiotic resistance biomarkers relating to multidrug resistance (MDR) efflux pumps, drug detoxification enzymes, ribosomal protection proteins, and secretion systems, were inferred in the microbiome. This study provides theoretical insights on the microbiome and associated antibiotic resistance markers, important for the design of effective therapeutic and control decisions for tick-borne diseases in the SSA region.

10.
Metabolomics ; 17(7): 60, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34143280

RESUMO

INTRODUCTION: Research aimed at understanding intraspecific variation among corals could substantially increase understanding of coral biology and improve outcomes of active restoration efforts. Metabolomics is useful for identifying physiological drivers leading to variation among genotypes and has the capacity to improve our selection of candidate corals that express phenotypes beneficial to restoration. OBJECTIVES: Our study aims to compare metabolomic profiles among known, unique genotypes of the threatened coral Acropora cervicornis. In doing so, we seek information related to the physiological characteristics driving variation among genotypes, which could aid in identifying genets with desirable traits for restoration. METHODS: We applied proton nuclear magnetic resonance (1H-NMR) and liquid chromatography-mass spectrometry (LC-MS) to identify and compare metabolomic profiles for seven unique genotypes of A. cervicornis that previously exhibited phenotypic variation in a common garden coral nursery. RESULTS: Significant variation in polar and nonpolar metabolite profiles was found among A. cervicornis genotypes. Despite difficulties identifying all significant metabolites driving separation among genotypes, our data support previous findings and further suggest metabolomic profiles differ among various genotypes of the threatened species A. cervicornis. CONCLUSION: The implementation of metabolomic analyses allowed identification of several key metabolites driving separation among genotypes and expanded our understanding of the A. cervicornis metabolome. Although our research is specific to A. cervicornis, these findings have broad relevance for coral biology and active restoration. Furthermore, this study provides specific information on the understudied A. cervicornis metabolome and further confirmation that differences in metabolome structure could drive phenotypic variation among genotypes.


Assuntos
Antozoários , Metabolômica , Animais , Antozoários/genética , Região do Caribe , Espécies em Perigo de Extinção , Genótipo
11.
Heliyon ; 7(3): e06399, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33748472

RESUMO

Symbiotic associations with rhizospheric microbial communities coupled with the production of metabolites are key adaptive mechanisms by metallophytes to overcome metal stress. However, little is known about pseudometallophyte Phragmites australis interactions with fungal community despite commonly being applied in wetland phytoremediation of acid mine drainage (AMD). In this study, fungal community diversity and metabolomes production by rhizosphere and root endosphere of P. australis growing under three different AMD pollution gradient were analyzed. Our results highlight the following: 1) Ascomycota and Basidiomycota were dominant phyla, but the diversity and richness of taxa were lower within AMD sites with Penicillium, Candida, Saccharomycetales, Vishniacozyma, Trichoderma, Didymellaceae, and Cladosporium being enriched in the root endosphere and rhizosphere in AMD sites than non-AMD site; 2) non-metric multidimensional scaling (NMDS) of 73 metabolomes revealed spatially defined metabolite exudation by distinct root parts (rhizosphere vs endosphere) rather than AMD sites, with significant variability occurring within the rhizosphere correlating to pH, TDS, Fe, Cr, Cu and Zn content changes; 3) canonical correspondence analysis (CCA) confirmed specific rhizospheric fungal taxonomic changes are driven by pH, TDS, heavy metals, and stress-related metabolomes produced. This is the first report that gives a snapshot on the complex endophytic and rhizospheric fungal community structure and metabolites perturbations that may be key in the adaptability and metal phytoremediation by P. australis under AMD environment.

12.
Front Microbiol ; 12: 592725, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33716998

RESUMO

Southern Afrotemperate forests are small multi-layered and highly fragmented biodiversity rich biomes that support unique flora and fauna endemism. However, little is known about the microbial community and their contribution to these ecosystems. In this study, high throughput sequencing analysis was used to investigate the soil bacterial community structure and function, and understand the effect of local topography/geomorphological formations and land use patterns on a coastal scarp forest. Soil samples were collected from three forest topography sites: upper (steeper gradients, 30-55°; open canopy cover, <30%), mid (less steep, 15-30°; continuous forest canopy, >80%), and lower (flatter gradient, <15°; open canopy cover, 20-65%), and from the adjacent sugarcane farms. Results indicated that forest soils were dominated by members of phyla Proteobacteria (mainly members of α-proteobacteria), Actinobacteria, Acidobacteria, Firmicutes, and Planctomycetes, while Actinobacteria and to a lesser extent ß-proteobacteria and γ-proteobacteria dominated SC soils. The core bacterial community clustered by habitat (forest vs. sugarcane farm) and differed significantly between the forest topography sites. The Rhizobiales (genera Variibacter, Bradyrhizobium, and unclassified Rhizobiales) and Rhodospirallales (unclassified Rhodospirillum DA111) were more abundant in forest mid and lower topographies. Steeper forest topography (forest_upper) characterized by the highly leached sandy/stony acidic soils, low in organic nutrients (C and N) and plant densities correlated to significant reduction of bacterial diversity and richness, associating significantly with members of order Burkholderiales (Burkholderia-Paraburkholderia, Delftia, and Massilia) as the key indicator taxa. In contrast, changes in the total nitrogen (TN), soil organic matter (SOM), and high acidity (low pH) significantly influenced bacterial community structure in sugarcane farm soils, with genus Acidothermus (Frankiales) and uncultured Solirubrobacterales YNFP111 were the most abundant indicator taxa. Availability of soil nutrients (TN and SOM) was the strongest driver of metabolic functions related to C fixation and metabolism, N and S cycling; these processes being significantly abundant in forest than sugarcane farm soils. Overall, these results revealed that the local topographical/geomorphological gradients and sugarcane farming affect both soil characteristics and forest vegetation (canopy coverage), that indirectly drives the structure and composition of bacterial communities in scarp forest soils.

13.
Int Microbiol ; 24(3): 311-324, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33661427

RESUMO

Bacteria are primary agents of organic substrate metabolisation and elemental cycling in landfills. Two major bacterial groups, namely, Gram-positive (GP) and Gram-negative (GN), drive independent metabolic functions that contribute to waste stabilisation. There is a lack of explicit exploration of how these different bacterial guilds respond to changing carbon (C) availability and substrate depletion as landfills age and how landfill geochemistry regulates their distribution. This study investigated and compared the abundance and vertical distribution of GP and GN bacteria in 14- and 36-year-old municipal landfills and explored linkages among bacterial groups, nutrient elements, heavy metals and soil texture. We found higher GP bacteria in the 14-year-old landfill, while GN bacteria dominated the 36-year-old landfill. The non-metric multidimensional scaling (nMDS) analysis showed that dissimilarities in the relative abundance of the GP and GN bacteria were linked distinctly to landfill age, and not depth. In support of this inference, we further found that GP and GN bacteria were negatively correlated with heavy metals and essential nutrients in the 14- and 36-year-old landfills, respectively. Notably, the GP/GN ratio, an indicator of relative C available for bacterial mineralisation, was greater in the14-year-old landfill, suggesting greater C availability. Conversely, the C to N ratio was higher in the 36-year-old landfill, indicating lower N mineralisation. Collectively, the results of the study reveal key insights into how landfill ageing and stabilisation influence distinct functional shifts in the abundance of GP and GN bacteria, and these are mainly driven by changes in C and N bioavailability.


Assuntos
Carbono/análise , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Positivas/classificação , Bactérias Gram-Positivas/metabolismo , Metais Pesados/análise , Nutrientes/análise , Biodegradação Ambiental , DNA Bacteriano , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Reação em Cadeia da Polimerase , RNA Ribossômico 16S , Microbiologia do Solo , Instalações de Eliminação de Resíduos
14.
Curr Microbiol ; 78(4): 1177-1187, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33620555

RESUMO

Maize meal was allowed to undergo uncontrolled fermentation in the laboratory, in simulation of the traditional method of fermentation as practised in most African households. During the fermentation process, samples were collected daily for 11 days. Physico-chemical analysis of the fermenting slurry and metagenomics analysis of the microbial community using 16S rRNA demonstrated an interrelationship between the changes in the properties of the fermentation environment and the successional interplay of the microbial community. The first 24 h of fermentation at pH of 6.5 was characterised by the proliferation of probiotic Lactobacillus and Bifidobacterium, with their relative abundance being 40.7% and 29.9%, respectively. However, prolonged fermentation and a drop in pH from 5.3 to 3.7 caused a decline and finally an absence of these probiotic bacteria which were replaced by Clostridium spp. with a relative abundance of between 97% and 99% from day 5 to day 11. This study demonstrated that prolonged fermentation of maize meal is not ideally suited for the proliferation of probiotic nutritionally beneficial bacteria.


Assuntos
Bactérias , Zea mays , Bactérias/genética , Fermentação , Lactobacillus/genética , RNA Ribossômico 16S/genética
15.
Microbiologyopen ; 10(1): e1118, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33314739

RESUMO

Municipal landfills are hot spots of dynamic bioprocesses facilitated by complex interactions of a multifaceted microbiome, whose functioning in municipal landfills at different maturing stages is poorly understood. This study determined bacterial community composition, interaction conetworks, metabolic functions, and controlling physicochemical properties in two landfills aged 14 and 36 years. High throughput sequencing revealed a similar distribution of bacterial diversity, evenness, and richness in the 14- and 36-year-old landfills in the 0-90 cm depth. At deeper layers (120-150 cm), the 14-year-old landfill had significantly greater bacterial diversity and richness indicating that it is a more active microcosm than the 36-year-old landfill, where phylum Epsilonbacteraeota was overwhelmingly dominant. The taxonomic and functional diversity in the 14-year-old landfill was further reflected by the abundant presence of indicator genera Pseudomonas,Lutispora,Hydrogenspora, and Sulfurimonas coupled with the presence of biomarker enzymes associated with carbon (C), nitrogen (N), and sulfur (S) metabolism. Furthermore, canonical correspondence analysis revealed that bacteria in the 14-year-old landfill were positively correlated with high C, N, S, and phosphorus resulting in positive cooccurrence interactions. In the 36-year-old landfill, negative coexclusion interactions populated by members of N fixing Rhizobiales were dominant, with metabolic functions and biomarker enzymes predicting significant N fixation that, as indicated by interaction network, potentially inhibited ammonia-intolerant bacteria. Overall, our findings show that diverse bacterial community in the 14-year-old landfill was dominated by copiotrophs associated with positive conetworks, whereas the 36-year-old landfill was dominated by lithotrophs linked to coexclusion interactions that greatly reduced bacterial diversity and richness.


Assuntos
Bactérias/classificação , Bactérias/genética , Microbiota/genética , Resíduos Sólidos , Instalações de Eliminação de Resíduos , Biodegradação Ambiental , Biodiversidade , DNA Bacteriano/genética , Sequenciamento de Nucleotídeos em Larga Escala , Interações Microbianas/fisiologia , Fixação de Nitrogênio/fisiologia , Microbiologia do Solo
16.
J Infect Dis ; 224(4): 632-642, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-33367826

RESUMO

BACKGROUND: Ebola virus disease (EVD) supportive care strategies are largely guided by retrospective observational research. This study investigated the effect of EVD supportive care algorithms on duration of survival in a controlled nonhuman primate (NHP) model. METHODS: Fourteen rhesus macaques were challenged intramuscularly with a target dose of Ebola virus (1000 plaque-forming units; Kikwit). NHPs were allocated to intensive care unit (ICU)-like algorithms (n = 7), intravenous fluids plus levofloxacin (n = 2), or a control group (n = 5). The primary outcome measure was duration of survival, and secondary outcomes included changes in clinical laboratory values. RESULTS: Duration of survival was not significantly different between the pooled ICU-like algorithm and control groups (8.2 vs 6.9 days of survival; hazard ratio; 0.50; P = .25). Norepinephrine was effective in transiently maintaining baseline blood pressure. NHPs treated with ICU-like algorithms had delayed onset of liver and kidney injury. CONCLUSIONS: While an obvious survival difference was not observed with ICU-like care, clinical observations from this model may aid in EVD supportive care NHP model refinement.


Assuntos
Cuidados Críticos , Doença pelo Vírus Ebola , Unidades de Terapia Intensiva , Animais , Modelos Animais de Doenças , Ebolavirus , Doença pelo Vírus Ebola/terapia , Macaca mulatta , Primatas , Estudos Retrospectivos
17.
Environ Sci Pollut Res Int ; 28(3): 3217-3229, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32914303

RESUMO

Wastewater treatment plants (WWTPs) can be significant sources of antifungal resistant fungi, which can disseminate further in the environment by getting into rivers together with effluents discharged from WWTPs and pose a risk for human health. In this study, the presence of azole resistance was determined in fungal isolates from treated effluents of two WWTPs using the standard microdilution method from Clinical and Laboratory Standards Institute (CLSI). A total of 41 fungal isolates representing 23 fungal species and 16 fungal genera were obtained. Fungal genera related to the known human and/or plant pathogens such as Aspergillus, Fusarium, and Candida were detected. Among the observed species, the susceptibility of Aspergillus fumigatus and Fusarium oxysporum was tested against fluconazole (FCZ), ketoconazole (KTZ), itraconazole (ITZ), and voriconazole (VCZ). The isolate A. fumigatus was susceptible to KTZ, ITZ, and VCZ, while it showed resistance against FCZ. On the contrast, the isolate F. oxysporum showed resistance to KTZ, ITZ, and VCZ. Comparatively, VCZ showed highest activity against both A. fumigatus and F. oxysporum. Analysis of the gene Cyp51A for the A. fumigatus isolate showed no evidence of drug resistance that could be related to point mutations and/or tandem repeats in the gene. To the best of our knowledge, this is the first susceptibility test study on A. fumigatus and F. oxysporum isolates from the WWTPs of South Africa. In conclusion, this study indicated an urgent need for thorough investigation with larger group of fungal isolates from different regions of South Africa to broadly understand the role of WWTPs in the dissemination of azole antifungal drug resistance.


Assuntos
Antifúngicos , Purificação da Água , Antifúngicos/farmacologia , Aspergillus fumigatus/genética , Azóis/farmacologia , Farmacorresistência Fúngica , Proteínas Fúngicas , Fungos , Fusarium , Humanos , Testes de Sensibilidade Microbiana , África do Sul
18.
Environ Monit Assess ; 192(8): 519, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32671553

RESUMO

Despite increased public health concerns on the occurrences of potentially pathogenic/mycotoxigenic fungi in public drinking water system, dissemination of hygienically relevant fungi and their associated mycotoxins via distribution system under the dual burden of ageing infrastructure and ancillary distribution network lacking infrastructure for high-pressure water delivery systems is unknown. In this study, the diversity of fungi and occurrence of mycotoxins at 30 different points along treated piped water supply and ancillary distribution networks in Johannesburg, South Africa, were monitored for 12 months. Mycological analysis using cultural and molecular methods yielded 282 fungi belonging to phylum Ascomycota, having Aspergillus (91%), Penicillium (65%) and Trichoderma (31%) as dominant genera, with Aspergillus fumigatus, Penicillium citrinum, Purpureocillium lilacinum and Aspergillus flavus as the most prevalent species. Communal standpipe and reservoir outlets had significantly higher prevalence than other water samples. There was no strong correlation between total coliforms (r = 0.4266) and residual chlorine (r = - 0.1937), and fungal prevalence at p < 0.05. LC-MS/MS analysis detected aflatoxins B1, M1, G1 and G2 in 50, 9, 9 and 46% of water samples analysed, respectively, ranging between 0 and 3.18 ng/l. Deoxynivalenol (DON), 3-acetyl DON and 15-acetyl DON levels were between 8.4-96.1, 18.7-145.7 and 15.2-71.6 ng/l, respectively. However, the estimated average daily dose (ADD) for detected mycotoxins was below the tolerable daily intake (TDI), suggesting no toxicological risk. Presence of potentially mycotoxigenic fungi, despite the low toxicological risk, demonstrates a need for appropriate monitoring for fungi and mycotoxins in treated drinking water distribution systems for improved water quality and long-term public health assurance.


Assuntos
Água Potável , Micotoxinas/análise , Cromatografia Líquida , Monitoramento Ambiental , Contaminação de Alimentos/análise , Fungos , Saúde Pública , África do Sul , Espectrometria de Massas em Tandem , Qualidade da Água
19.
ScientificWorldJournal ; 2020: 7402846, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508539

RESUMO

An analysis of land cover changes (LCCs) was done in Image Forest Reserve (IFR) from August to October 2019. Free satellite images for 1990, 2004, and 2018 were downloaded from Landsat 5 (TM) and Landsat 8 (OLI) available through the USGS portal. Ground surveys were conducted using systematically set plots of 20 m × 40 m to identify the existing land cover types and human illegal activities. Geographical coordinates for each of these plots were recorded using handheld GPS. We witnessed the changes of land cover types in the three decades. Forest had contracted, while shrubland and grassland and woodland had expanded within IFR. Between 1990 and 2004, woodland, bareland and rocky outcrops, shrubland, and grassland had consistently decreased though at a different rate of change, while forest has increased between the same assessment periods. The period of 2004-2018 has shown a consistent increase at different rates in woodland, bareland and rocky outcrops, shrubland, and grassland at a different rate of change, while forest has decreased between the same assessment periods. Further study is needed, bylaws and laws should be implemented, participatory forest management should be encouraged, beekeeping and ecotourism should be introduced, provision of regular education to the community by the Tanzania Forest Service (TFS) should be encouraged, and awareness creation should be made.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Monitoramento Ambiental , Geografia , Humanos , Tanzânia
20.
Sci Total Environ ; 717: 137284, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32084697

RESUMO

Isinuka Springs at Port St Johns in the Eastern Cape Province of South Africa is a traditional spa sacred to the AmaMpondo tribe of the Xhosa speaking people. The bathing pond is considered to have healing powers both spiritually and therapeutically. Hundreds of people flock into the spiritual pond every weekend for both recreational and its spiritual healing power. In this study, we present the metal concentrations of the bathing pond (sediments and water samples), the hole drinking water as well as sediments from a cave situated at the bottom of the hill harbouring the bathing pond. Our results show that the geophagic clays from the cave and bathing pond has elevated concentrations of earth metals (up to 134,506 mg kg-1 for calcium), trace metals (up to 36,272 mg kg-1 for iron) and toxic metals (up to 25 mg kg-1 for lead). The levels of both essential and toxic metals in the drinking water were above the recommended daily limits except for zinc and copper. Aluminium, a metal with antibacterial activity was as high as 71,792 mg kg-1 in pond sediments. Even though the results show elevated concentrations especially for toxic metals, the study observes that the spa remains limited in potential for metal toxipathy because the frequency of contact with the pond is minimal estimated at once a week by traditional healers and once a month for locals while visitors from other parts of the province rarely come back.


Assuntos
Nascentes Naturais/química , Balneologia , Argila , Monitoramento Ambiental , Sedimentos Geológicos , Metais Pesados , Solo , África do Sul , Água , Poluentes Químicos da Água
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