Search results for "microbial"
showing 10 items of 2041 documents
Exposure to bioaerosols and noise at a Finnish dry waste treatment plant
2004
Repeated measurements were carried out during two different campaigns between 1998 and 2001 to assess the occupational hygiene at a Finnish dry waste treatment plant. The analytical determinations were done in four different places within the processing hall of the plant: near a conveyor belt, near a jigger screen, near an after-crusher and near a bailer. Measurements were also carried out in a coffee room for employees. Concentrations of bacteria, fungi and actinomycetes were determined by two methods (six-stage impactor and Camnea method) and levels of endotoxins, dust and noise were also investigated. High concentrations of microbes and endotoxins and the noise level were found to be a …
Emerging technologies for enhanced removal of residual antibiotics from source-separated urine and wastewaters: A review.
2022
Antibiotic residues are of significant concern in the ecosystem because of their capacity to mediate antibiotic resistance development among environmental microbes. This paper reviews recent technologies for the abatement of antibiotics from human urine and wastewaters. Antibiotics are widely distributed in the aquatic environment as a result of the discharge of municipal sewage. Their existence is a cause for worry due to the potential ecological impact (for instance, antibiotic resistance) on bacteria in the background. Numerous contaminants that enter wastewater treatment facilities and the aquatic environment, as a result, go undetected. Sludge can act as a medium for some chemicals to …
Occurrence of antibiotics in the aquatic environment
1999
The recent monitoring of drug residues in the aquatic environment has gained much interest as many pharmaceutical compounds can frequently be found in sewage treatment plant (STP) effluents and river water at concentrations up to several microgram/l. This article describes the analysis of various water samples for 18 antibiotic substances, from the classes of macrolid antibiotics, sulfonamides, penicillins and tetracyclines. Samples were preconcentrated via lyophilization and quantified using HPLC-electrospray-tandem-mass spectrometry. The investigated STP effluents and surface water samples showed frequent appearance of an erythromycin degradation product, roxithromycin and sulfamethoxazol…
Wastewater constituents impact biofilm microbial community in receiving streams
2022
Microbial life in natural biofilms is dominated by prokaryotes and microscopic eukaryotes living in dense association. In stream ecosystems, microbial biofilms influence primary production, elemental cycles, food web interactions as well as water quality. Understanding how biofilm communities respond to anthropogenic impacts, such as wastewater treatment plant (WWTP) effluent, is important given the key role of biofilms in stream ecosystem function. Here, we implemented 16S and 18S rRNA gene sequencing of stream biofilms upstream (US) and downstream (DS) of WWTP effluents in four Swiss streams to test how bacterial and eukaryotic communities respond to wastewater constituents. Stream biofil…
A Wickerhamomyces anomalus Killer Strain in the Malaria Vector Anopheles stephensi
2013
The yeast Wickerhamomyces anomalus has been investigated for several years for its wide biotechnological potential, especially for applications in the food industry. Specifically, the antimicrobial activity of this yeast, associated with the production of Killer Toxins (KTs), has attracted a great deal of attention. The strains of W. anomalus able to produce KTs, called "killer" yeasts, have been shown to be highly competitive in the environment. Different W. anomalus strains have been isolated from diverse habitats and recently even from insects. In the malaria mosquito vector Anopheles stephensi these yeasts have been detected in the midgut and gonads. Here we show that the strain of W. a…
Quantifying transmission fitness costs of multi-drug resistant tuberculosis.
2021
As multi-drug resistant tuberculosis (MDR-TB) continues to spread, investigating the transmission potential of different drug-resistant strains becomes an ever more pressing topic in public health. While phylogenetic and transmission tree inferences provide valuable insight into possible transmission chains, phylodynamic inference combines evolutionary and epidemiological analyses to estimate the parameters of the underlying epidemiological processes, allowing us to describe the overall dynamics of disease spread in the population. In this study, we introduce an approach to Mycobacterium tuberculosis (M. tuberculosis) phylodynamic analysis employing an existing computationally efficient mod…
Ethnopharmacology, phytochemistry and biological activity of Erodium species: a review
2019
Erodium spp. is a genus that can be found in all continents that has been traditionally used in folk medicine to treat many diseases such as hemorrhage, dermatological disorders, indigestion, and inflammatory diseases. Moreover, Erodium leaves have been used for the preparation of salads, omelets, sandwiches, sauces and soups, among other food products. The objective of this review was to show the recent and relevant studies about extraction of bioactive compounds, the phytochemical characterization, the potential biological activities and toxicological evidence reported in both in vitro and in vivo studies from Erodium spp. In addition, the use of Erodium spp. as natural compounds against …
Chemical Composition and Antimicrobial Activity of the Essential Oil from Flowers of Eryngium triquetrum (Apiaceae) Collected Wild in Sicily
2016
The chemical composition of the essential oil from flowers of Eringium triquetrum Vahl. collected in Sicily was evaluated by GC and GC-MS. The main components were pulegone (50.6%), piperitenone (30.5%) and menthone (7.0%). Comparison of this oil with other studied oils of Eringium species is discussed. The oil showed good antibacterial and antifungal activities against some microorganisms that infest historical art works.
Synthèse et réactivité chimiques et électrochimiques de dérivés d'imidazoliums : vers des procédés éco-responsables
2015
This work deals with the use of electrochemistry as a tool for alternative synthesis of new azolium-based molecules.A new electrosynthesis method was developed for the synthesis of imidazolium carboxylates (masked carbenes) leading to a wide library of compounds. This approach was compared to already reported chemical syntheses. In the current context of sustainable development, bio based products have been synthesized and optimization of the process was achieved in order to reduce waste and energy consumption.The key role of the hydrogenoxalate anion was demonstrated in the synthesis of ionic liquids and/or imidazolium salts. Some of them were employed as recyclable catalysts for Fischer e…
Long-term performance of peat biofilters treating ethyl acetate, toluene, and its mixture in air.
2006
Three laboratory-scale peat biofilters were operated at 90 s empty bed residence time (EBRT) for over a year. Biodegradation of ethyl acetate, toluene, or a 1:1 mixture were investigated. In first stage, inlet concentration was progressively increased from 0.4 to 4.5 g/m3. The maximum elimination capacity (EC) found for ethyl acetate was 190 gC/m3·h, and it was not affected by toluene. The maximum EC found for toluene as a sole contaminant was 150 gC/m3·h, but the presence of ethyl acetate decreased the toluene maximum EC to 80 gC/m3·h. From respirometry monitoring, values of 3.19 g CO2/gC and 3.06 g CO2/gC for pure ethyl acetate and pure toluene, respectively, were found, with overall yiel…