Search results for: microbial communities

Authors: Zhichao Li

Abstract:

This project has treated the waste-water that contains the nitrogen heterocyclic aromatic hydrocarbons, by using the phenol-induced microbial communities. The treatment of nitrogen heterocyclic aromatic hydrocarbons is a difficult problem for coking waste-water treatment. Pyridine, quinoline and indole are three kinds of most common nitrogen heterocyclic compounds in the f, and treating these refractory organics biologically has always been a research focus. The phenol-degrading bacteria can be used in the enhanced biological treatment effectively, and has a good treatment effect. Therefore, using the phenol-induced microbial communities to treat the coking waste-water can remove multiple pollutants concurrently, and improve the treating efficiency of coking waste-water. Experiments have proved that the phenol-induced microbial communities can degrade the nitrogen heterocyclic ring aromatic hydrocarbon efficiently.

Keywords: phenol, nitrogen heterocyclic aromatic hydrocarbons, phenol-degrading bacteria, microbial communities, biological treatment technology

Procedia PDF Downloads 170

Authors: Priyanka Dargode, Suhas Gore, Manju Sharma, Arvind Lali

Abstract:

Anaerobic digestion has been widely used for production of methane from different biowastes. However, the complexity of microbial communities involved in the process is poorly understood. The performance of biogas production process concerning the process productivity is closely coupled to its microbial community structure and syntrophic interactions amongst the community members. The present study aims at understanding taxonomic variations occurring in any starter inoculum when acclimatised to different lignocellulosic biomass (LBM) feedstocks relating to time of digestion. The work underlines use of high throughput Next Generation Sequencing (NGS) for validating the changes in taxonomic patterns of microbial communities. Biomethane Potential (BMP) batches were set up with different pretreated and non-pretreated LBM residues using the same microbial consortium and samples were withdrawn for studying the changes in microbial community in terms of its structure and predominance with respect to changes in metabolic profile of the process. DNA of samples withdrawn at different time intervals with reference to performance changes of the digestion process, was extracted followed by its 16S rRNA amplicon sequencing analysis using Illumina Platform. Biomethane potential and substrate consumption was monitored using Gas Chromatography(GC) and reduction in COD (Chemical Oxygen Demand) respectively. Taxonomic analysis by QIIME server data revealed that microbial community structure changes with different substrates as well as at different time intervals. It was observed that biomethane potential of each substrate was relatively similar but, the time required for substrate utilization and its conversion to biomethane was different for different substrates. This could be attributed to the nature of substrate and consequently the discrepancy between the dominance of microbial communities with regards to different substrate and at different phases of anaerobic digestion process. Knowledge of microbial communities involved would allow a rational substrate specific consortium design which will help to reduce consortium adaptation period and enhance the substrate utilisation resulting in improved efficacy of biogas process.

Keywords: amplicon sequencing, biomethane potential, community predominance, taxonomic analysis

Procedia PDF Downloads 491

Authors: Zeina Bourhane, Anders Lanzen, Christine Cagnon, Olfa Ben Said, Cristiana Cravo-Laureau, Robert Duran

Abstract:

The anthropogenic pressure in coastal areas increases dramatically with the exploitation of environmental resources. Biomonitoring coastal areas are crucial to determine the impact of pollutants on bacterial communities in soils and sediments since they provide important ecosystem services. However, relevant biomonitoring tools allowing fast determination of the ecological status are yet to be defined. Microbial ecology approaches provide useful information for developing such microbial monitoring tools reporting on the effect of environmental stressors. Chemical and microbial molecular approaches were combined in order to determine microbial bioindicators for assessing the ecological status of soil and river ecosystems around the Ichkeul Lake (Tunisia), an area highly impacted by human activities. Samples were collected along soil/river/lake continuums in three stations around the Ichkeul Lake influenced by different human activities at two seasons (summer and winter). Contaminant pressure indexes (PI), including PAHs (Polycyclic aromatic hydrocarbons), alkanes, and OCPs (Organochlorine pesticides) contents, showed significant differences in the contamination level between the stations with seasonal variation. Bacterial communities were characterized by 16S ribosomal RNAs (rRNA) gene metabarcoding. Although microgAMBI indexes, determined from the sequencing data, were in accordance with contaminant contents, they were not sufficient to fully explain the PI. Therefore, further microbial indicators are still to be defined. The comparison of bacterial communities revealed the specific microbial assemblage for soil, river, and lake sediments, which were significantly correlated with contaminant contents and PI. Such observation offers the possibility to define a relevant set of bioindicators for reporting the effects of human activities on the microbial community structure. Such bioindicators might constitute useful monitoring tools for the management of microbial communities in coastal areas.

Keywords: bacterial communities, biomonitoring, contamination, human impacts, microbial bioindicators

Procedia PDF Downloads 126

Authors: Anza-Vhudziki Mboyi, Ilunga Kamika, Maggy Momba

Abstract:

The aim of this study was to ascertain the survival limit and capability of commonly found wastewater protozoan (Aspidisca sp, Trachelophyllum sp, and Peranema sp) and bacterial (Bacillus licheniformis, Brevibacillus laterosporus, and Pseudomonas putida) species to remove COD while exposed to commercial nanomaterials under varying pH conditions. The experimental study was carried out in modified mixed liquor media adjusted to various pH levels (pH 2, 7 and 10), and a comparative study was performed to determine the difference between the cytotoxicity effects of commercial zinc oxide (nZnO) and silver (nAg) nanomaterials (NMs) on the target wastewater microbial communities using standard methods. The selected microbial communities were exposed to lethal concentrations ranging from 0.015 g/L to 40 g/L for nZnO and from 0.015 g/L to 2 g/L for nAg for a period of 5 days of incubation at 30°C (100 r/min). Compared with the absence of NMs in wastewater mixed liquor, the relevant environmental concentration ranging between 10 µg/L and 100 µg/L, for both nZnO and nAg caused no adverse effects, but the presence of 20 g of nZnO/L and 0.65 g of nAg/L significantly inhibited microbial growth. Statistical evidence showed that nAg was significantly more toxic compared to nZnO, but there was an insignificant difference in toxicity between microbial communities and pH variations. A significant decrease in the removal of COD by microbial populations was observed in the presence of NMs with a moderate correlation of r = 0.3 to r = 0.7 at all pH levels. It was evident that there was a physical interaction between commercial NMs and target wastewater microbial communities; although not quantitatively assessed, cell morphology and cell death were observed. Such phenomena suggest the high resilience of the microbial community, but it is the accumulation of NMs that will have adverse effects on the performance in terms of COD removal.

Keywords: bacteria, biological treatment, chemical oxygen demand (COD) and nanomaterials, consortium, pH, protozoan

Procedia PDF Downloads 260

Authors: Lukasz Szydlowski, Jiri Ehlich, Igor Goryanin

Abstract:

We demonstrate a single chamber, 96-well-plated based Microbial Fuel Cell (MFC) with printed, electronic components. This invention is aimed at robust selection of electrogenic microbial community under specific conditions, e.g., electrode potential, pH, nutrient concentration, salt concentration that can be altered within the 96 well plate array. This invention enables robust selection of electrogenic microbial community under the homogeneous reactor, with multiple conditions that can be altered to allow comparative analysis. It can be used as a standalone technique or in conjunction with other selective processes, e.g., flow cytometry, microfluidic-based dielectrophoretic trapping. Mobile conductive elements, like carbon paper, carbon sponge, activated charcoal granules, metal mesh, can be inserted inside to increase the anode surface area in order to collect electrogenic microorganisms and to transfer them into new reactors or for other analytical works. An array of 96-well plate allows this device to be operated by automated pipetting stations.

Keywords: bioengineering, electrochemistry, electromicrobiology, microbial fuel cell

Procedia PDF Downloads 108

Authors: Jhovana Silvia Escobar Ortega, Ines Eugenia Garcia De Salamone

Abstract:

Cover crops are an agri-technological alternative to improve all properties of soils. Cover crops such as oats and rye could be used to reduce erosion and favor system sustainability when they are grown in the same agricultural cycle of the soybean crop. This crop is very profitable but its low contribution of easily decomposable residues, due to its low C/N ratio, leaves the soil exposed to erosive action and raises the need to reduce its monoculture. Furthermore, inoculation with the plant growth promoting rhizobacteria contributes to the implementation, development and production of several cereal crops. However, there is little information on its effects on forage crops which are often used as cover crops to improve soil quality. In order to evaluate the effect of combined inoculation with Azospirillum brasilense and Pseudomonas fluorescens on rhizosphere microbial communities, field experiments were conducted in the west of Buenos Aires province, Argentina, with a split-split plot randomized complete block factorial design with three replicates. The factors were: type of cover crop, inoculation and fertilization. In the main plot two levels of fertilization 0 and 7 40-0-5 (NPKS) were established at sowing. Rye (Secale cereale cultivar Quehué) and oats (Avena sativa var Aurora.) were sown in the subplots. In the sub-subplots two inoculation treatments are applied without and with application of a combined inoculant with A. brasilense and P. fluorescens. Due to the growth of cover crops has to be stopped usually with the herbicide glyphosate, rhizosphere soil of 0-20 and 20-40 cm layers was sampled at three sampling times which were: before glyphosate application (BG), a month after glyphosate application (AG) and at soybean harvest (SH). Community level of physiological profiles (CLPP) and Shannon index of microbial diversity (H) were obtained by multivariate analysis of Principal Components. Also, the most probable number (MPN) of nitrifiers and cellulolytics were determined using selective liquid media for each functional group. The CLPP of rhizosphere microbial communities showed significant differences between sampling times. There was not interaction between sampling times and both, types of cover crops and inoculation. Rhizosphere microbial communities of samples obtained BG had different CLPP with respect to the samples obtained in the sampling times AG and SH. Fertilizer and depth of sampling also caused changes in the CLPP. The H diversity index of rhizosphere microbial communities of rye in the sampling time BG were higher than those associated with oats. The MPN of both microbial functional types was lower in the deeper layer since these microorganisms are mostly aerobic. The MPN of nitrifiers decreased in rhizosphere of both cover crops only AG. At the sampling time BG, the NMP of both microbial types were larger than those obtained for AG and SH. This may mean that the glyphosate application could cause fairly permanent changes in these microbial communities which can be considered bio-indicators of soil quality. Inoculation and fertilizer inputs could be included to improve management of these cover crops because they can have a significant positive effect on the sustainability of the agro-ecosystem.

Keywords: community level of physiological profiles, microbial diversity, plant growth promoting rhizobacteria, rhizosphere microbial communities, soil quality, system sustainability

Procedia PDF Downloads 367

Authors: Isabel N. Sierra-Garcia, Maria J. Ferreira, Sandro Figuereido, Newton Gomes, Helena Silva, Angela Cunha

Abstract:

Plant-associated microbial communities are considered crucial in the adaptation of halophytes to coastal environments. The plant microbiota can be horizontally acquired from the environment or vertically transmitted from generation to generation via seeds. Recruiting of the microbial communities by the plant is affected by geographical location, soil source, host genotype, and cultivation practice. There is limited knowledge reported on the microbial communities in halophytes the influence of biotic and abiotic factors. In this work, the microbiota associated with the halophyte Salicornia ramosissima was investigated to determine whether the structure of bacterial communities is influenced by host genotype or soil source. For this purpose, two contrasting sites where S. ramosissima is established in the estuarine system of the Ria de Aveiro were investigated. One site corresponds to a natural salt marsh where S. ramosissima plants are present (wild plants), and the other site is a former salt pan that nowadays are subjected to intensive crop production of S. ramosissima (crop plants). Bacterial communities from the rhizosphere, seeds and root endosphere of S. ramossisima from both sites were investigated by sequencing bacterial 16S rRNA gene using the Illumina MiSeq platform. The analysis of the sequences showed that the three plant-associated compartments, rhizosphere, root endosphere, and seed endosphere, harbor distinct microbiomes. However, bacterial richness and diversity were higher in seeds of wild plants, followed by rhizosphere in both sites, while seeds in the crop site had the lowest diversity. Beta diversity measures indicated that bacterial communities in root endosphere and seeds were more similar in both wild and crop plants in contrast to rhizospheres that differed by local, indicating that the recruitment of the similar bacterial communities by the plant genotype is active in regard to the site. Moreover, bacterial communities from the root endosphere and rhizosphere were phylogenetically more similar in both sites, but the phylogenetic composition of seeds in wild and crop sites was distinct. These results indicate that cultivation practices affect the seed microbiome. However, minimal vertical transmission of bacteria from seeds to adult plants is expected. Seeds from the crop site showed higher abundances of Kushneria and Zunongwangia genera. Bacterial members of the classes Alphaprotebacteria and Bacteroidia were the most ubiquitous across sites and compartments and might encompass members of the core microbiome. These findings indicate that bacterial communities associated with S. ramosissima are more influenced by host genotype rather than local abiotic factors or cultivation practices. This study provides a better understanding of the composition of the plant microbiota in S. ramosissima , which is essential to predict the interactions between plant and associated microbial communities and their effects on plant health. This knowledge is useful to the manipulations of these microbial communities to enhance the health and productivity of this commercially important plant.

Keywords: halophytes, plant microbiome, Salicornia ramosissima, agriculture

Procedia PDF Downloads 125

Authors: Hana Barak, Alex Sivan, Ariel Kushmaro

Abstract:

Microorganisms are the most diverse and abundant life forms on Earth and account for a large portion of the Earth’s biomass and biodiversity. To date though, our knowledge regarding microbial life is lacking, as it is based mainly on information from cultivated organisms. Indeed, microbiologists have borrowed from astrophysics and termed the ‘uncultured microbial majority’ as ‘microbial dark matter’. The realization of how diverse and unexplored microorganisms are, actually stems from recent advances in molecular biology, and in particular from novel methods for sequencing microbial small subunit ribosomal RNA genes directly from environmental samples termed next-generation sequencing (NGS). This has led us to use NGS that generates several gigabases of sequencing data in a single experimental run, to identify and classify environmental samples of microorganisms. In metagenomics sequencing analysis (both 16S and shotgun), sequences are compared to reference databases that contain only small part of the existing microorganisms and therefore their taxonomy assignment may reveal groups of unknown microorganisms or origins. These unknowns, or the ‘microbial sequences dark matter’, are usually ignored in spite of their great importance. The goal of this work was to develop an improved bioinformatics method that enables more complete analyses of the microbial communities in numerous environments. Therefore, NGS was used to identify previously unknown microorganisms from three different environments (industrials wastewater, Negev Desert’s rocks and water wells at the Arava valley). 16S rRNA gene metagenome analysis of the microorganisms from those three environments produce about ~4 million reads for 75 samples. Between 0.1-12% of the sequences in each sample were tagged as ‘Unassigned’. Employing relatively simple methodology for resequencing of original gDNA samples through Sanger or MiSeq Illumina with specific primers, this study demonstrates that the mysterious ‘Unassigned’ group apparently contains sequences of candidate phyla. Those unknown sequences can be located on a phylogenetic tree and thus provide a better understanding of the ‘sequences dark matter’ and its role in the research of microbial communities and diversity. Studying this ‘dark matter’ will extend the existing databases and could reveal the hidden potential of the ‘microbial dark matter’.

Keywords: bacteria, bioinformatics, dark matter, Next Generation Sequencing, unknown

Procedia PDF Downloads 213

Authors: Rama Devi Kyatham, D. Ashok, K. S. K. Rao Patnaik, Raju Bathula

Abstract:

We have shown the importance of pyrazoles as anti-microbial chemical entities. These compounds have generally been considered significant due to their wide range of pharmacological acivities and their discovery motivates new avenues of research.The proposed pyrazoles were synthesized and evaluated for their anti-microbial activities. The Synthesized compounds were analyzed by different spectroscopic methods.

Keywords: pyrazoles, validation, resistant microbial strains, anti-microbial activities

Procedia PDF Downloads 130

Authors: Xiaoxing Ye

Abstract:

To investigate complex rumen microbial communities, 16S ribosomal RNA (rRNA) sequencing is widely used. Here, we evaluated the impact of bioinformatics pipelines on the observation of OTUs and taxonomic classification of 750 cattle rumen microbial samples by comparing three commonly used pipelines (LotuS, UPARSE, and QIIME) with Usearch. In LotuS-based analyses, 189 archaeal and 3894 bacterial OTUs were observed. The observed OTUs for the Usearch analysis were significantly larger than the LotuS results. We discovered 1495 OTUs for archaea and 92665 OTUs for bacteria using Usearch analysis. In addition, taxonomic assignments were made for the rumen microbial samples. All pipelines had consistent taxonomic annotations from the phylum to the genus level. A difference in relative abundance was calculated for all microbial levels, including Bacteroidetes (QIIME: 72.2%, Usearch: 74.09%), Firmicutes (QIIME: 18.3%, Usearch: 20.20%) for the bacterial phylum, Methanobacteriales (QIIME: 64.2%, Usearch: 45.7%) for the archaeal class, Methanobacteriaceae (QIIME: 35%, Usearch: 45.7%) and Methanomassiliicoccaceae (QIIME: 35%, Usearch: 31.13%) for archaeal family. However, the most prevalent archaeal class varied between these two annotation pipelines. The Thermoplasmata was the top class according to the QIIME annotation, whereas Methanobacteria was the top class according to Usearch.

Keywords: cattle rumen, rumen microbial, 16S rRNA gene sequencing, bioinformatics pipeline

Procedia PDF Downloads 45

Authors: M. P. Casiraghi, C. M. Quintella, P. Almeida

Abstract:

Paraffinic oils were submitted to microbial action. The microorganisms consisted of bacteria of the genera Pseudomonas sp and Bacillus lincheniforms. The alterations in interfacial tension were determined using a tensometer and applying the hanging drop technique at room temperature (299 K ±275 K). The alteration in the constitution of the paraffins was evaluated by means of gas chromatography. The microbial activity was observed to reduce interfacial tension by 54 to 78%, as well as consuming the paraffins C19 to C29 and producing paraffins C36 to C44. The LIFirr technique made it possible to determine the microbial action quickly.

Keywords: paraffins, biosurfactants, LIFirr, microbial activity

Procedia PDF Downloads 469

Authors: Niranjan Mukherjee, Burga Braun, Ulrich Szewzyk

Abstract:

Recalcitrant pharmaceuticals are increasingly found in urban water systems forced by demographic changes. The groundwater-surface water interface, or the hyporheic zone, is known for its impressive self-purification capacity of water bodies. Redox gradients present in this zone provide a wide range of electron acceptors and harbour diverse microbial communities. Biotic transformations of pharmaceuticals in this zone have been demonstrated, but not much information is available on the kind of communities bringing about these transformations. Therefore, bioreactors using sediment from the hyporheic zone of a river in Berlin were set up and fed with iopromide, a recalcitrant iodinated X-ray contrast medium. Iopromide, who’s many oxic and anoxic transformation products have been characterized, was shown to be transformed in such a bioreactor as it passes along the gradient. Many deiodinated transformation products of iopromide could be identified at the outlet of the reactor. In our experiments, it was seen that at the same depths of the column, the transformation of iopromide increased over time. This could be an indication of the microbial communities in the sediment adapting to iopromide. The hyporheic zone, with its varying redox conditions, mainly due to the upwelling and downwelling of surface and groundwater levels, could potentially provide microorganisms with conditions for the complete transformation of recalcitrant pharmaceuticals.

Keywords: iopromide, hyporheic zone, recalcitrant pharmaceutical, redox gradients

Procedia PDF Downloads 92

Authors: Judith Mogouong, Philippe Constant, Robert Lavallee, Claude Guertin

Abstract:

The emerald ash borer (EAB) is an exotic wood borer insect native from China, which is associated with important environmental and economic damages in North America. Beetles are known to be vectors of microbial communities related to their adaptive capacities. It is now established that environmental stress factors may induce physiological events on the host trees, such as phytochemical changes. Consequently, that may affect the establishment comportment of herbivorous insect. Considering the number of insects collected on ash trees (insects’ density) as an abiotic factor related to stress damage, the aim of our study was to explore the dynamic of EAB gut microbial community genome (microbiome) when facing that factor and to monitor its diversity. Insects were trapped using specific green Lindgren© traps. A gradient of the captured insect population along the St. Lawrence River was used to create three levels of insects’ density (low, intermediate, and high). After dissection, total DNA extracted from insect guts of each level has been sent for amplicon sequencing of bacterial 16S rRNA gene and fungal ITS2 region. The composition of microbial communities among sample appeared largely diversified with the Simpson index significantly different across the three levels of density for bacteria. Add to that; bacteria were represented by seven phyla and twelve classes, whereas fungi were represented by two phyla and seven known classes. Using principal coordinate analysis (PCoA) based on Bray Curtis distances of 16S rRNA sequences, we observed a significant variation between the structure of the bacterial communities depending on insects’ density. Moreover, the analysis showed significant correlations between some bacterial taxa and the three classes of insects’ density. This study is the first to present a complete overview of the bacterial and fungal communities associated with the gut of EAB base on culture-independent methods, and to correlate those communities with a potential stress factor of the host trees.

Keywords: gut microbiome, DNA, 16S rRNA sequences, emerald ash borer

Procedia PDF Downloads 366

Authors: Gómez Romero Jacob, García Peña Elvia Inés

Abstract:

The co-digestion process of crude cheese whey (CCW) with fruit vegetable waste (FVW) for biohydrogen production was investigated in batch and continuous systems, in stirred 1.8 L bioreactors at 37°C. Five different C/N ratios (7, 17, 21, 31, and 46) were tested in batch systems. While, in continuous system eight conditions were evaluated, hydraulic retention time (from 60 to 10 h) and organic load rate (from 21.96 to 155.87 g COD/L d). Data in batch tests showed a maximum specific biohydrogen production rate of 10.68 mmol H2/Lh and a biohydrogen yield of 449.84 mL H2/g COD at a C/N ratio of 21. In continuous co-digestion system, the optimum hydraulic retention time and organic loading rate were 17.5 h and 80.02 g COD/L d, respectively. Under these conditions, the highest volumetric production hydrogen rate (VPHR) and hydrogen yield were 11.02 mmol H2/L h, 800 mL H2/COD, respectively. A pyrosequencing analysis showed that the main acclimated microbial communities for co-digestion studies consisted of Bifidobacterium, with 85.4% of predominance. Hydrogen producing bacteria such as Klebsiella (9.1%), Lactobacillus (0.97%), Citrobacter (0.21%), Enterobacter (0.27%), and Clostridium (0.18%) were less abundant at this culture period. The microbial population structure was correlated with the lactate, acetate, and butyrate profiles obtained. Results demonstrated that the co-digestion of CCW with FVW improves biohydrogen production due to a better nutrient balance and improvement of the system’s buffering capacity.

Keywords: acclimatation, biohydrogen, co-digestion, microbial community

Procedia PDF Downloads 514

Authors: Sean T. S. Wei, Joy D. Van Nostrand, Annapoorna Maitrayee Ganeshram, Stephen B. Pointing

Abstract:

McMurdo Dry Valleys are a largely ice-free polar desert protected by international treaty as an Antarctic special managed area. The terrestrial landscape is dominated by oligotrophic mineral soil with extensive rocky outcrops. Several environmental stresses: low temperature, lack of liquid water, UV exposure and oligotrophic substrates, restrict the major biotic component to microorganisms. The bacterial diversity and the putative physiological capacity of microbial communities of quartz rocks (hypoliths) and soil of a maritime-influenced Dry Valleys were interrogated by two metagenomic approaches: 454 pyro-sequencing and Geochp DNA microarray. The most abundant phylum in hypoliths was Cyanobacteria (46%), whereas in solils Actinobacteria (31%) were most abundant. The Proteobacteria and Bacteriodetes were the only other phyla to comprise >10% of both communities. Carbon fixation was indicated by photoautotrophic and chemoautotrophic pathways for both hypolith and soil communities. The fungi accounted for polymer carbon transformations, particularly for aromatic compounds. The complete nitrogen cycling was observed in both communities. The fungi in particular displayed pathways related to ammonification. Environmental stress response pathways were common among bacteria, whereas the nutrient stress response pathways were more widely present in bacteria, archaea and fungi. The diversity of bacterialphage was also surveyed by Geochip. Data suggested that different substrates supported different viral families: Leviviridae, Myoviridae, Podoviridae and Siphoviridiae were ubiquitous. However, Corticoviridae and Microviridae only occurred in wetter soils.

Keywords: Antarctica, hypolith, soil, dry valleys, geochip, functional diversity, stress response

Procedia PDF Downloads 412

Authors: JooYoung Lee, Rasheed Hussain

Abstract:

Understanding the relationships among communities of users is the key to blueprint the evolution of human society. Majority of people are equipped with GPS devices, such as smart phones and smart cars, which can trace their whereabouts. In this paper, we discover communities of device users based on real locations in a given time frame. We, then, study the associations of discovered communities, referred to as temporal communities, and generate temporal and probabilistic association rules. The rules describe how strong communities are associated. By studying the generated rules, we can automatically extract underlying hierarchies of communities and permanent communities such as work places.

Keywords: association rules, community detection, evolution of communities, spatiotemporal

Procedia PDF Downloads 325

Authors: Gianmaria Califano, Júlio Augusto Lucena Maciel, Olfa Zarrouk, Miguel Damasio, Jose Silvestre, Ana Margarida Fortes

Abstract:

Global warming, with rapid and sudden changes in meteorological conditions, is one of the major constraints to ensuring agricultural and crop resilience in the Mediterranean regions. Several strategies are being adopted to reduce the pressure of drought stress on grapevines at regional and local scales: improvements in the irrigation systems, adoption of interline cover crops, and adaptation of pruning techniques. However, still, more can be achieved if also microbial compartments associated with plants are considered in crop management. It is known that the microbial community change according to several factors such as latitude, plant variety, age, rootstock, soil composition and agricultural management system. Considering the increasing pressure of the biotic and abiotic stresses, it is of utmost necessity to also evaluate the effects of drought on the microbiome associated with the grapevine, which is a commercially important crop worldwide. In this study, we characterize the diversity and the structure of the microbial community under three long-term irrigation levels (100% ETc, 50% ETc and rain-fed) in a drought-tolerant grapevine cultivar present worldwide, Syrah. To avoid the limitations of culture-dependent methods, amplicon sequencing with target primers for bacteria and fungi was applied to the same soil samples. The use of the DNeasy PowerSoil (Qiagen) extraction kit required further optimization with the use of lytic enzymes and heating steps to improve DNA yield and quality systematically across biological treatments. Target regions (16S rRNA and ITS genes) of our samples are being sequenced with Illumina technology. With bioinformatic pipelines, it will be possible to obtain a characterization of the bacterial and fungal diversity, structure and composition. Further, the microbial communities will be assessed for their functional activity, which remains an important metric considering the strong inter-kingdom interactions existing between plants and their associated microbiome. The results of this study will lay the basis for biotechnological applications: in combination with the establishment of a bacterial library, it will be possible to explore the possibility of testing synthetic microbial communities to support plant resistance to water scarcity.

Keywords: microbiome, metabarcoding, soil, vinegrape, syrah, global warming, crop sustainability

Procedia PDF Downloads 76

Authors: Tiisetso Mpai, Sanjay K. Jaiswal, Felix D. Dakora

Abstract:

The South African Cape fynbos biome is a global biodiversity hotspot. This biome contains a diversity of endemic shrub legumes, including Polhillia, Wiborgia, and Wiborgiella species, which are important for ecotourism as well as for improving soil fertility status. This is due to their proven N₂-fixing abilities when in association with compatible soil bacteria. In fact, Polhillia, Wiborgia, and Wiborgiella species have been reported to derive over 61% of their needed nitrogen through biological nitrogen fixation and to exhibit acid and alkaline phosphatase activity in their rhizospheres. Thus, their interactions with soil microbes may explain their survival mechanisms under the continued summer droughts and acidic, nutrient-poor soils in this region. However, information regarding their rhizosphere microbiome is still unavailable, yet it is important for Fynbos biodiversity management. Therefore, the aim of this study was to assess the microbial community structures associated with rhizosphere soils of Polhillia pallens, Polhillia brevicalyx, Wiborgia obcordata, Wiborgia sericea, and Wiborgiella sessilifolia growing at different locations of the South African Cape fynbos, during the wet and dry seasons. The hypothesis is that the microbial communities in these legume rhizospheres are the same type and are not affected by the growing season due to the restricted habitat of these wild fynbos legumes. To obtain the results, DNA was extracted from 0.5 g of each rhizosphere soil using PowerSoil™ DNA Isolation Kit, and sequences were obtained using the 16S rDNA Miseq Illumina technology. The results showed that in both seasons, bacteria were the most abundant microbial taxa in the rhizosphere soils of all five legume species, with Actinobacteria showing the highest number of sequences (about 30%). However, over 19.91% of the inhabitants in all five legume rhizospheres were unclassified. In terms of genera, Mycobacterium and Conexibacter were common in rhizosphere soils of all legumes in both seasons except for W. obcordata soils sampled during the dry season, which had Dehalogenimonas as the major inhabitant (6.08%). In conclusion, plant species and season were found to be the main drivers of microbial community structure in Cape fynbos, with the wet season being more dominant in shaping microbial diversity relative to the dry season. Wiborgia obcordata had a greater influence on microbial community structure than the other four legume species.

Keywords: 16S rDNA, Cape fynbos, endemic legumes, microbiome, rhizosphere

Procedia PDF Downloads 115

Authors: Shubhangi R. Deshmukh, Anupam B. Soni

Abstract:

Clean water and electricity are vital services needed in all communities. Bio-degradation of wastewater contaminants and desalination technologies are the best possible alternatives for the global shortage of fresh water supply. Osmotic microbial fuel cell (OMFC) is a versatile technology that uses microorganism (used for biodegradation of organic waste) and membrane technology (used for water purification) for wastewater treatment and energy generation simultaneously. This technology is the combination of microbial fuel cell (MFC) and forward osmosis (FO) processes. OMFC can give more electricity and clean water than the MFC which has a regular proton exchange membrane. FO gives many improvements such as high contamination removal, lower operating energy, raising high proton flux than other pressure-driven membrane technology. Lower concentration polarization lowers the membrane fouling by giving osmotic water recovery without extra cost. In this review paper, we have discussed the principle, mechanism, limitation, and application of OMFC technology reported to date. Also, we have interpreted the experimental data from various literature on the water recovery and electricity generation assessed by a different component of OMFC. The area of producing electricity using OMFC has further scope for research and seems like a promising route to wastewater treatment.

Keywords: forward osmosis, microbial fuel cell, osmotic microbial fuel cell, wastewater treatment

Procedia PDF Downloads 151

Authors: Khethiwe Mtshali, Zamantungwa T. H. Khumalo, Stanford Kwenda, Ismail Arshad, Oriel M. M. Thekisoe

Abstract:

Ecologically, the gut, mammary glands and bloodstream consist of distinct microbial communities of commensals, mutualists and pathogens, forming a complex ecosystem of niches. The by-products derived from these body sites i.e. faeces, milk and blood, respectively, have many uses in rural communities where they aid in the facilitation of day-to-day household activities and occasional rituals. Thus, although livestock rearing plays a vital role in the sustenance of the livelihoods of rural communities, it may serve as a potent reservoir of different pathogenic organisms that could have devastating health and economic implications. This study aimed to simultaneously explore the microbial profiles of corresponding faecal, milk and blood samples from lactating cows using 16S rRNA metagenomic sequencing. Bacterial communities were inferred through the Divisive Amplicon Denoising Algorithm 2 (DADA2) pipeline coupled with SILVA database v138. All downstream analyses were performed in R v3.6.1. Alpha-diversity metrics showed significant differences between faeces and blood, faeces and milk, but did not vary significantly between blood and milk (Kruskal-Wallis, P < 0.05). Beta-diversity metrics on Principal Coordinate Analysis (PCoA) and Non-Metric Dimensional Scaling (NMDS) clustered samples by type, suggesting that microbial communities of the studied niches are significantly different (PERMANOVA, P < 0.05). A number of taxa were significantly differentially abundant (DA) between groups based on the Wald test implemented in the DESeq2 package (Padj < 0.01). The majority of the DA taxa were significantly enriched in faeces than in milk and blood, except for the genus Anaplasma, which was significantly enriched in blood and was, in turn, the most abundant taxon overall. A total of 30 phyla, 74 classes, 156 orders, 243 families and 408 genera were obtained from the overall analysis. The most abundant phyla obtained between the three body sites were Firmicutes, Bacteroidota, and Proteobacteria. A total of 58 genus-level taxa were simultaneously detected between the sample groups, while bacterial signatures of at least 8 of these occurred concurrently in corresponding faeces, milk and blood samples from the same group of animals constituting a pool. The important taxa identified in this study could be categorized into four potentially pathogenic clusters: i) arthropod-borne; ii) food-borne and zoonotic; iii) mastitogenic and; iv) metritic and abortigenic. This study provides insight into the microbial composition of bovine faeces, milk, and blood and its extent of overlapping. It further highlights the potential risk of disease occurrence and transmission between the animals and the inhabitants of the sampled rural community, pertaining to their unsanitary practices associated with the use of cattle by-products.

Keywords: microbial profiling, 16S rRNA, NGS, feces, milk, blood, lactating cows, small-scale farmers

Procedia PDF Downloads 77

Authors: Tsedekech Gebremeskel Weldmichael, Tamas Szegi, Lubangakene Denish, Ravi Kumar Gangwar, Erika Micheli, Barbara Simon

Abstract:

Following the 1992 Earth Summit in Rio de Janeiro, soil biodiversity has been recognized globally as a crucial player in guaranteeing the functioning of soil and a provider of several ecosystem services essential for human well-being. The microbial fraction of the soil is a vital component of soil fertility as soil microbes play key roles in soil aggregate formation, nutrient cycling, humification, and degradation of pollutants. Soil fauna, such as earthworms, have huge impacts on soil organic matter dynamics, nutrient cycling, and infiltration and distribution of water in the soil. Currently, land-use change has been a global concern as evidence accumulates that it adversely affects soil biodiversity and the associated ecosystem goods and services. In this study, we examined the patterns of soil microbial respiration (SMR) and earthworm (abundance, biomass, and species richness) across three land-use types (grassland, arable land, and forest) in Hungary. The objectives were i) to investigate whether there is a significant difference in SMR and earthworm (abundance, biomass, and species richness) among land-use types. ii) to determine the key soil properties that best predict the variation in SMR and earthworm communities. Soil samples, to a depth of 25 cm, were collected from the surrounding areas of seven soil profiles. For physicochemical parameters, soil organic matter (SOM), pH, CaCO₃, E₄/E₆, available nitrogen (NH₄⁺-N and NO₃⁻-N), potassium (K₂O), phosphorus (P₂O₅), exchangeable Ca²⁺, Mg²⁺, soil moisture content (MC) and bulk density were measured. The analysis of SMR was determined by basal respiration method, and the extraction of earthworms was carried out by hand sorting method as described by ISO guideline. The results showed that there was no statistically significant difference among land-use types in SMR (p > 0.05). However, the highest SMR was observed in grassland soils (11.77 mgCO₂ 50g⁻¹ soil 10 days⁻¹) and lowest in forest soils (8.61 mgCO₂ 50g⁻¹ soil 10 days⁻¹). SMR had strong positive correlations with exchangeable Ca²⁺ (r = 0.80), MC (r = 0.72), and exchangeable Mg²⁺(r = 0.69). We found a pronounced variation in SMR among soil texture classes (p < 0.001), where the highest value in silty clay loam soils and the lowest in sandy soils. This study provides evidence that agricultural activities can negatively influence earthworm communities, in which the arable land had significantly lower earthworm communities compared to forest and grassland respectively. Overall, in our study, land use type had minimal effects on SMR whereas, earthworm communities were profoundly influenced by land-use type particularly agricultural activities related to tillage. Exchangeable Ca²⁺, MC, and texture were found to be the key drivers of the variation in SMR.

Keywords: earthworm community, land use, soil biodiversity, soil microbial respiration, soil property

Procedia PDF Downloads 100

Authors: Afiq Mohd Fahmi, Tony Gutierrez, Sebastian Hennige

Abstract:

Increasing amounts of CO₂ entering the marine environment, also known as ocean acidification, is documented as having harmful impacts on a variety of marine organisms. When considering the future risk of hydrocarbon pollution, which is generally detrimental to marine life as well, this needs to consider how OA-induced changes to microbial communities will compound this since hydrocarbon degradation is influenced by the community-level microbial response. This study aims to evaluate the effects of increased atmospheric CO₂ conditions and oil enrichment on the phytoplankton-associated bacterial communities. Faroe Shetland Channel (FSC) is a subarctic region in the northeast Atlantic where crude oil extraction has recently been expanded. In the event of a major oil spill in this region, it is vital that we understand the response of the bacterial community and its consequence on primary production within this region—some phytoplankton communities found in the ocean harbor hydrocarbon-degrading bacteria that are associated with its psychosphere. Surface water containing phytoplankton and bacteria from FSC were cultured in ambient and elevated atmospheric CO₂ conditions for 4 days of acclimation in microcosms before introducing 1% (v/v) of crude oil into the microcosms to simulate oil spill conditions at sea. It was found that elevated CO₂ conditions do not significantly affect the chl a concentration, and exposure to crude oil detrimentally affected chl a concentration up to 10 days after exposure to crude oil. The diversity and richness of the bacterial community were not significantly affected by both CO₂ treatment and oil enrichment. The increase in the relative abundance of known hydrocarbon degraders such as Oleispira, Marinobacter and Halomonas indicates potential for biodegradation of crude oil, while the resilience of dominant taxa Colwellia, unclassified Gammaproteobacteria, unclassified Rnodobacteria and unclassified Halomonadaceae could be associated with the recovery of microalgal community 13 days after oil exposure. Therefore, the microbial community from the subsurface of FSC has the potential to recover from crude oil pollution even under elevated CO₂ (750 ppm) conditions.

Keywords: phytoplankton, bacteria, crude oil, ocean acidification

Procedia PDF Downloads 194

Authors: Shruti Malviya, Chris Bowler

Abstract:

Analysis of microbial eukaryotic diversity is fundamental to understanding ecosystems’ structure, biology, and ecology. Diatoms (Stramenopiles, Bacillariophyceae) are one of the most diverse and ecologically prominent groups of phytoplankton. This study was performed to enhance the understanding of global biodiversity patterns and structure of planktonic diatom communities across the world's oceans. We used the metabarcoding data set generated from the biological samples and associated environmental data collected during the Tara Oceans (2009-2013) global circumnavigation covering all major oceanic provinces. A total of ~18 million diatom V9-18S rDNA tags from 126 sampling stations, constituting 631 size-fractionated plankton communities were generated. Using ~250,000 unique diatom metabarcodes, the global diatom distribution and diversity across size classes, genus and ecological niches was assessed. Notably, our analysis revealed: (i) a new estimate of the total number of planktonic diatom species, (ii) a considerable unknown diversity and exceptionally high diversity in the open ocean, and (iii) complex diversity patterns across oceanic provinces. Also, co-occurrence of several ribotypes in locations separated by great geographic distances (equatorial stations) demonstrated a widespread but not ubiquitous distribution. This work provides a comprehensive perspective on diatom distribution and diversity in the world’s oceans and elaborates interconnections between associated theories and underlying drivers. It shows how meta-barcoding approaches can provide a framework to investigate environmental diversity at a global scale, which is deemed as an essential step in answering various ecological research questions. Consequently, this work also provides a reference point to explore how microbial communities will respond to environmental conditions.

Keywords: diatoms, Tara Oceans, biodiversity, metabarcoding

Procedia PDF Downloads 111

Authors: Abimbola M. Enitan, John O. Odiyo, Feroz M. Swalaha

Abstract:

The study of microbial ecology and their function in anaerobic digestion processes are essential to control the biological processes. This is to know the symbiotic relationship between the microorganisms that are involved in the conversion of complex organic matter in the industrial wastewater to simple molecules. In this study, diversity and quantity of bacterial community in the granular sludge taken from the different compartments of a full-scale upflow anaerobic sludge blanket (UASB) reactor treating brewery wastewater was investigated using polymerase chain reaction (PCR) and real-time quantitative PCR (qPCR). The phylogenetic analysis showed three major eubacteria phyla that belong to Proteobacteria, Firmicutes and Chloroflexi in the full-scale UASB reactor, with different groups populating different compartment. The result of qPCR assay showed high amount of eubacteria with increase in concentration along the reactor’s compartment. This study extends our understanding on the diverse, topological distribution and shifts in concentration of microbial communities in the different compartments of a full-scale UASB reactor treating brewery wastewater. The colonization and the trophic interactions among these microbial populations in reducing and transforming complex organic matter within the UASB reactors were established.

Keywords: bacteria, brewery wastewater, real-time quantitative PCR, UASB reactor

Procedia PDF Downloads 227

Authors: Messaouda Belaid, Salima Kebbouche-Gana

Abstract:

The negative effect of the Varroa bee colony is very important. They cause morphological and physiological changes, causing a decrease in performance of individuals and long-term death of the colony. Indirectly, they weaken the bees become much more sensitive to the different pathogenic organisms naturally present in the colony. This work aims to research secondary infections of microbial origin occurred in the worker bee nurse due to parasitism by Varroa destructor. The feeding behaviour of Varroa may causes damaging host integument. The results show that the microbial contamination enable to be transmitted into honeybee heamocoel are Bacillus sp, Pseudomonas sp, Enterobacter, Aspergillus.

Keywords: honeybee, Apis mellifera intermissa, microbial contamination, Varroa destructor

Procedia PDF Downloads 368

Authors: O. A. Babalola, A. F Adekunle, F. Oladeji, A. T. Osungbade, O. A. Akinlaja

Abstract:

Optimizing microbiological activities in an organic crop production system is crucial to the realization of optimum growth and development of the crops. Field and pot experiments were conducted to assess soil microbial activities, growth and yield of tomato varieties in response to 4 rates of composted plant and animal residues. The compost rates were 0, 5, 10 and 20 t ha-1, and improved Ibadan and Ibadan local constituted the varieties. Fungi population, microbial biomass nitrogen, cellulase and proteinase activities were significantly higher (P≤ 0.05) at the rhizosphere of the local variety than that of improved variety. This led to a significantly higher number of branches, plant height, leaf area, number of fruits and less days to maturity in the local variety. Furthermore, compost-amended soil had significantly higher microbial populations, microbial biomass N, P and C, enzyme activities, soil N, P and organic carbon than control, but amendment of 20 t ha-1 gave significantly higher values than other compost rates. Consequently, growth parameters and tissue N significantly increased in all compost treatments while dry matter yield and weight of fruits were significantly higher in soil amended with 20 t ha-1. Correlation analysis showed that microbial activities at 6 weeks after transplanting (6 WAT) were more consistently and highly correlated with growth and yield parameters. It was concluded that microbial activities could be optimized to improve the yield of the two tomato varieties in an organic production system, through the application of compost, particularly at 20 t ha-1.

Keywords: compost, microbial activities, microbial contribution, tomato growth and yield

Procedia PDF Downloads 224

Authors: Anshu Siwach, Qianlai Zhuang, Ratul Baishya

Abstract:

Context: This study focuses on the influence of moss cover and seasonality on soil microbial biomass and enzymatic activity in different Central Himalayan temperate forest types. Soil microbial biomass and enzymes are key indicators of microbial communities in soil and provide information on soil properties, microbial status, and organic matter dynamics. The activity of microorganisms in the soil varies depending on the vegetation type and environmental conditions. Therefore, this study aims to assess the effects of moss cover, seasons, and different forest types on soil microbial biomass carbon (SMBC), soil microbial biomass nitrogen (SMBN), and soil enzymatic activity in the Central Himalayas, Uttarakhand, India. Research Aim: The aim of this study is to evaluate the levels of SMBC, SMBN, and soil enzymatic activity in different temperate forest types under the influence of two ground covers (soil with and without moss cover) during the rainy and winter seasons. Question Addressed: This study addresses the following questions: 1. How does the presence of moss cover and seasonality affect soil microbial biomass and enzymatic activity? 2. What is the influence of different forest types on SMBC, SMBN, and enzymatic activity? Methodology: Soil samples were collected from different forest types during the rainy and winter seasons. The study utilizes the chloroform-fumigation extraction method to determine SMBC and SMBN. Standard methodologies are followed to measure enzymatic activities, including dehydrogenase, acid phosphatase, aryl sulfatase, β-glucosidase, phenol oxidase, and urease. Findings: The study reveals significant variations in SMBC, SMBN, and enzymatic activity under different ground covers, within the rainy and winter seasons, and among the forest types. Moss cover positively influences SMBC and enzymatic activity during the rainy season, while soil without moss cover shows higher values during the winter season. Quercus-dominated forests, as well as Cupressus torulosa forests, exhibit higher levels of SMBC and enzymatic activity, while Pinus roxburghii forests show lower levels. Theoretical Importance: The findings highlight the importance of considering mosses in forest management plans to improve soil microbial diversity, enzymatic activity, soil quality, and health. Additionally, this research contributes to understanding the role of lower plants, such as mosses, in influencing ecosystem dynamics. Conclusion: The study concludes that moss cover during the rainy season significantly influences soil microbial biomass and enzymatic activity. Quercus and Cupressus torulosa dominated forests demonstrate higher levels of SMBC and enzymatic activity, indicating the importance of these forest types in sustaining soil microbial diversity and soil health. Including mosses in forest management plans can improve soil quality and overall ecosystem dynamics.

Keywords: moss cover, seasons, soil enzymes, soil microbial biomass, temperate forest types

Procedia PDF Downloads 33

Authors: Muwanga Zake, Johnnie Wycliffe Frank

Abstract:

Developing communities accommodating institutions of Higher Education (HE) often have no capacity to pay for HE and so do not contribute values and do not participate in Quality Assurance. Only governments, academia, employers and professional organisations determine values, QA and curricula in HE. A gap between the values in HE and those desirable in local communities and environments leads to erroneous conceptions of the purposes of HE, and to graduates who hardly fit into those local communities. Unemployment and under-utilization of local resources are thus expected. As a way to improve and make HE more relevant for local communities and environment, public perceptions, values and needs should be researched and HE courses should relate with local values and environments. Communities should participate in QA.

Keywords: values, quality assurance, higher education, utilization

Procedia PDF Downloads 414

Authors: M. F. R. Zuthi, H. H. Ngo, W. S. Guo, S. S. Chen, N. C. Nguyen, L. J. Deng, T. D. C Tran

Abstract:

Sustaining a desired rate of oxygen transfer for microbial activity is a matter of major concern for Biological Wastewater Treatment (MBR). The study reported in the paper was aimed at assessing the effects of microbial products on the Specific Oxygen Uptake Rate (SOUR) in a Conventional Membrane Bioreactor (CMBR) and that in a Sponge Submerged MBR (SSMBR). The production and progressive accumulation of Soluble Microbial Products (SMP) and Bound-Extracellular Polymeric Substances (BEPS) were found affecting the SOUR of the microorganisms which varied at different stages of operation of the MBR systems depending on the variable concentrations of the SMP/bEPS. The effect of bEPS on the SOUR was stronger in the SSMBR compared to that of the SMP, while relative high concentrations of SMP had adverse effects on the SOUR of the CMBR system. Of the different mathematical correlations analyzed in the study, logarithmic mathematical correlations could be established between SOUR and bEPS in SSMBR, and similar correlations could also be found between SOUR and SMP concentrations in the CMBR.

Keywords: microbial products, microbial activity, specific oxygen uptake rate, membrane bioreactor

Procedia PDF Downloads 264

Authors: Saleh Alkarri, Dimple Sharma, Teresa M. Bergholz, Muhammad Rabnawaz

Abstract:

Aims: Develop a methodology for the fabrication of anti-microbial polypropylene (PP) surfaces with (i) leachable copper, (II) chloride dihydrate (CuCl₂·₂H₂O) and (ii) non-leachable magnesium hydroxide (Mg(OH)₂) biocides. Methods and Results: Two methodologies are used to develop anti-microbial PP surfaces. One method involves melt-blending and subsequent injection molding, where the biocide additives were compounded with PP and subsequently injection-molded. The other method involves the thermal embossing of anti-microbial agents on the surface of a PP substrate. The obtained biocide-bearing PP surfaces were evaluated against E. coli K-12 MG1655 for 0, 4, and 24 h to evaluate their anti-microbial properties. The injection-molded PP bearing 5% CuCl2·₂H₂O showed a 6-log reduction of E. coli K-12 MG1655 after 24 h, while only 1 log reduction was observed for PP bearing 5% Mg(OH)2. The thermally embossed PP surfaces bearing CuCl2·2H2O and Mg(OH)₂ particles (at a concentration of 10 mg/mL) showed 3 log and 4 log reduction, respectively, against E.coli K-12 MG1655 after 24 h. Conclusion: The results clearly demonstrate that CuCl₂·2H₂O conferred anti-microbial properties to PP surfaces that were prepared by both injection molding as well as thermal embossing approaches owing to the presence of leachable copper ions. In contrast, the non-leachable Mg(OH)₂ imparted anti-microbial properties only to the surface prepared via the thermal embossing technique. Significance and Impact of The Study: Plastics with leachable biocides are effective anti-microbial surfaces, but their toxicity is a major concern. This study provides a fabrication methodology for non-leachable PP-based anti-microbial surfaces that are potentially safer. In addition, this strategy can be extended to many other plastics substrates.

Keywords: anti-microbial activity, E. coli K-12 MG1655, copper (II) chloride dihydrate, magnesium hydroxide, leachable, non-leachable, compounding, thermal embossing

Procedia PDF Downloads 48