Search results for "Gradation"
showing 10 items of 1275 documents
Efficiency in hydrocarbon degradation and biosurfactant production by Joostella sp. A8 when grown in pure culture and consortia
2017
Abstract Joostella strains are emerging candidates for biosurfactant production. Here such ability was analyzed for Joostella strain A8 in comparison with Alcanivorax strain A53 and Pseudomonas strain A6, all previously isolated from hydrocarbon enrichment cultures made of polychaete homogenates. In pure cultures Joostella sp. A8 showed the highest stable emulsion percentage (78.33%), hydrophobicity rate (62.67%), and an optimal surface tension reduction during growth in mineral medium supplemented with diesel oil (reduction of about 12 mN/m), thus proving to be highly competitive with Alcanivorax and Pseudomonas strains. During growth in pure culture different level of biodegradation were …
Environmental metabarcoding reveals contrasting microbial communities at two poplar phytomanagement sites
2016
The aim of the present study is to deepen the current understanding of the microbial communities at two poplar phytomanagement sites to reveal the environmental factors that drive the abundance, diversity and composition of microbial communities. A soil analysis revealed that the two soils displayed contrasting physico-chemical characteristics, with significant lower pH and higher Cd, Zn and Mn CaCl2-extractable fractions at Leforest site, compared with Pierrelaye site. The fungal and bacterial community profiles in the poplar roots and soils were assessed through Illumina MiSeq sequencing. Diversity indices and β-diversity measures illustrated that the root microbial communities were well …
Kinetics of vinyl acetate biodegradation by Pseudomonas fluorescens PCM 2123
2018
Abstract The microbial degradation of vinyl acetate (VA) by Pseudomonas fluorescens PCM 2123 strain was studied in both batch and continuous modes. The purpose of the experiments was to determine the kinetic model of the cell growth and biodegradation rate of vinyl acetate (VA), which was the sole carbon and energy source for tested microorganisms. The experiments, carried out in a batch reactor for several initial concentrations of growth substrate in the liquid phase ranging from 18.6 to 373 gsubstrate·m−3 (gs·m−3) made it possible to choose the kinetic model and to estimate its constants. The Haldane inhibitory model with the values of constants: μm = 0.1202 h−1, KS = 17.195 gs·m−3, Ki =…
The gut microbiota of the wood-feeding termite Reticulitermes lucifugus (Isoptera; Rhinotermitidae)
2016
Termite gut is host to a complex microbial community consisting of prokaryotes, and in some cases flagellates, responsible for the degradation of lignocellulosic material. Here we report data concerning the analysis of the gut microbiota of Reticulitermes lucifugus (Rossi), a lower termite species that lives in underground environments and is widespread in Italy, where it causes damage to wood structures of historical and artistic monuments. A 16S rRNA gene clone library revealed that the R. lucifugus gut is colonized by members of five phyla in the domain Bacteria: Firmicutes (49 % of clones), Proteobacteria (24 %), Spirochaetes (14 %), the candidatus TG1 phylum (12 %), and Bacteroidetes (…
Metabolic and process engineering for biodesulfurization in Gram-negative bacteria
2017
32 p.-2 fig.-1 tab.
Effects of alternative electron acceptors on the activity and community structure of methane-producing and consuming microbes in the sediments of two…
2017
The role of anaerobic CH4 oxidation in controlling lake sediment CH4 emissions remains unclear. Therefore, we tested how relevant EAs (SO42−, NO3−, Fe3+, Mn4+, O2) affect CH4 production and oxidation in the sediments of two shallow boreal lakes. The changes induced to microbial communities by the addition of Fe3+ and Mn4+ were studied using next-generation sequencing targeting the 16S rRNA and methyl-coenzyme M reductase (mcrA) genes and mcrA transcripts. Putative anaerobic CH4-oxidizing archaea (ANME-2D) and bacteria (NC 10) were scarce (up to 3.4% and 0.5% of archaeal and bacterial 16S rRNA genes, respectively), likely due to the low environmental stability associated with shallow depths.…
Microbial communities of polluted sub-surface marine sediments
2018
Abstract Microbial communities of coastal marine sediment play a key role in degradation of petroleum contaminants. Here the bacterial and archaeal communities of sub-surface sediments (5–10 cm) of the chronically polluted Priolo Bay (eastern coast of Sicily, Italy), contaminated mainly by n-alkanes and biodegraded/weathered oils, were characterized by cultural and molecular approaches. 16S-PCR-DGGE analysis at six stations, revealed that bacterial communities are highly divergent and display lower phylogenetic diversity than the surface sediment; sub-surface communities respond to oil supplementation in microcosms with a significant reduction in biodiversity and a shift in composition; the…
Analytical insight into degradation processes of aminopolyphosphonates as potential factors that induce cyanobacterial blooms
2017
Aminopolyphosphonates (AAPs) are commonly used industrial complexones of metal ions, which upon the action of biotic and abiotic factors undergo a breakdown and release their substructures. Despite the low toxicity of AAPs towards vertebrates, products of their transformations, especially those that contain phosphorus and nitrogen, can affect algal communities. To verify whether such chemical entities are present in water ecosystems, much effort has been made in developing fast, inexpensive, and reliable methods for analyzing phosphonates. However, unfortunately, the methods described thus far require time-consuming sample pretreatment and offer relatively high values of the limit of detect…
Understanding the performance of an AnMBR treating urban wastewater and food waste via model simulation and characterization of the microbial populat…
2018
[EN] An anaerobic membrane bioreactor (AnMBR) pilot plant treating kitchen food waste (FW) jointly with urban wastewater was run for 536 days. Different operational conditions were tested varying the sludge retention time (SRT), the hydraulic retention time (HRT) and the penetration factor (PF) of food waste disposers. COD removal efficiency exceeded 90% in all tested conditions. The joint treatment resulted in an almost 3-fold increase in methane production (at 70 days of SRT, 24 h HRT and 80% PF) in comparison with the treatment of urban wastewater only. Mathematical model simulations and Illumina technology were used to obtain in-depth information of this outstanding process performance.…
Uterine disorders affecting female fertility: what are the molecular functions altered in endometrium?
2020
[EN]: Objective:To determine the molecular functions of genes exhibiting altered expression in the endometrium of women with uterine disorders affecting fertility. Design: Retrospective analysis integrating case and control data from multiple cohorts with endometrium gene expression in women with uterine disorders. Setting: Infertility research department affiliated with a university hospital. Patient(s): Two hundred and forty women, 121 of whom were controls, 119 of whom had endometrial adenocarcinoma (ADC), recurrent implantation failure (RIF), recurrent pregnancy loss (RPL), or stage II–IV endometriosis. Intervention(s): None. Main Outcome Measure(s): Genomewide gene expression and alter…