scholarly journals Study of biodegradation of Poly(butylene adipate co-terephthalate) (PBAT) by maritime microorganisms from the Atlhantic Coast of Recife-PE (Brazil)

2021 ◽  
Vol 10 (17) ◽  
pp. e164101724579
Author(s):  
Lhaira Souza Barreto ◽  
Erika Emanuele Gomes da Silva ◽  
Mariana Alves Henrique ◽  
Josiane Dantas Viana Barbosa ◽  
Sara Horácio de Oliveira ◽  
...  
Keyword(s):  
Marine Environment ◽  
Heterotrophic Bacteria ◽  
Coastal Region ◽  
Degradation Process ◽  
Static System ◽  
Covalent Bonds ◽  
Sulfate Reducing ◽  
High Concentrations ◽  
Reducing Bacteria ◽  
Bacterial Groups

Biodegradable polymers undergo a degradation process resulting from the action of microorganisms such as bacteria, fungi and algae. Poly(butylene adipate co-terephthalate) (PBAT) is considered a biodegradable synthetic polymer, even if its degradation has been confirmed under industrial composting conditions, the investigation of its degradation in the marine environment is still limited. Therefore, this work aims to study the biodegradation in the marine environment, of the biodegradable polymer (PBAT), and for that, it was submerged in a static system, using seawater from the coastal region of Pernambuco/Brazil as a fluid. The samples were studied by chemical, thermal and microbiological analyses, after 7, 14, 30, 90, 120 and 180 days of immersion. Microbiological analyzes indicated that aerobic heterotrophic bacteria (AHB), anaerobic heterotrophic bacteria (AnHB) and iron precipitating bacteria (IPB) were quantified in the system at all times at high concentrations, with the exception of Sulfate reducing bacteria (SRB), fungi and Pseudomonas that showed lower concentrations compared to other bacterial groups. Biodegradation was observed by the percentage of mass loss of approximately 2.25%. In the DSC, the expansion of melting peaks after exposure to the marine environment was noted, while the TGA did not show changes in the curve trends. The FTIR showed that no new band appeared, nor displacement, since the vibrations of the covalent bonds of the groups are present regardless of the biodegradation. Indicating that no significant microbiological degradation of PBAT was observed.

Biological Mechanisms of H2S Formation in Sewer Pipes

1992 ◽  
Vol 26 (3-4) ◽  
pp. 907-914 ◽  
Author(s):  
A. Attal ◽  
M. Brigodiot ◽  
P. Camacho ◽  
J. Manem
Keyword(s):  
Suspended Solid ◽  
Urban Wastewater ◽  
Biological Mechanisms ◽  
Sewer Pipes ◽  
Sulfate Reducing ◽  
Biological Phenomena ◽  
Low Concentrations ◽  
Production Of Hydrogen ◽  
High Concentrations ◽  
Reducing Bacteria

The purpose of this study is to gain a better understanding of the biological phenomena involved in the production of hydrogen sulfide in urban wastewater (UWW) systems. It is found that the UWW itself naturally possesses the biomass needed to consume the sulfates. These heterotrophic sulfate-reducing bacteria populations, though immediately active in strict anaerobic conditions, are present only in very low concentrations in the UWW. A concentration of them was studied within the pressure pipes, in the form of deposits, and this justifies the high concentrations of sulfides measured in certain wastewater networks. There are two reasons why the ferrous sulfate used as a treatment in any wastewater networks should not cause the production of additional sulfides. Firstly, the sulfate consumption kinetics are always too slow, relative to the residence time of the water in the pipe, for all of the sulfates to be consumed anyway. Secondly, the amount of assimilable carbon, soluble carbon, and carbon from suspended solid (SS) hydrolysis is insufficient.

Quantitative ecology of psychrophilic bacteria in an aquatic environment and characterization of heterotrophic bacteria from permanently cold sediments

1979 ◽  
Vol 25 (12) ◽  
pp. 1433-1442 ◽  
Author(s):  
L. G. Leduc ◽  
G. D. Ferroni
Keyword(s):  
Incubation Temperature ◽  
Heterotrophic Bacteria ◽  
Sulfate Reducing Bacteria ◽  
Gram Positive ◽  
Sulfate Reducing ◽  
Quantitative Ecology ◽  
Physiological Group ◽  
Sulfur Oxidizing ◽  
Reducing Bacteria

Aerobic heterotrophic bacteria, anaerobic heterotrophic bacteria, ammonifying bacteria, sulfur-oxidizing bacteria, and sulfate-reducing bacteria were quantitated in Fairbank Lake, an oligotrophic to mesotrophic lake with a permanently cold hypolimnion, as a function of depth in three seasons. Representatives of each physiological group were recovered at an incubation temperature of 2 °C and for all the physiological groups the 2 °C counts were usually higher than the 37 °C counts, although sulfate-reducing bacteria were not recoverable at an incubation temperature of 37 °C. In addition, the numbers of each physiological type were generally higher in the sediments than in the water column, except in the case of sulfate-reducing bacteria for which the counts were low and often below the detection limit. Aerobic heterotrophic bacteria usually outnumbered the other physiological groups surveyed, and winter minima were characteristic of some of the physiological groups. A relatively stable density of anaerobic heterotrophic bacteria, as a function of sediment depth, was observed when the incubation temperature was 2 °C. At 37 °C, these anaerobes were not detected, and this was true for sulfate-reducing bacteria at both temperatures.Heterotrophic bacterial isolates from the permanently cold sediments were examined with regard to Gram reaction, the obligate or facultative nature of anaerobes, ability to use ecologically important substrates, psychrophilic type, and temperature range for growth. Isolates recovered at 2 °C were predominantly Gram-negative bacilli, whereas isolates recovered at 37 °C were predominantly Gram-positive bacilli. The anaerobic isolates were mainly Gram-positive bacilli regardless of the isolation temperature, and most of those examined were obligately anaerobic. Many of the isolates tested were positive for gelatinase, chitinase, amylase, and lipase, but none was positive for cellulase. Most of the sediment isolates were facultatively psychrophilic and a considerable fraction of the 37 °C isolates were facultative psychrophiles.

Analysis of Bacterial Kill Versus Corrosion From Use of Common Oilfield Biocides

2010 ◽  
Author(s):  
Vic Keasler ◽  
Brian Bennett ◽  
Heather McGinley
Keyword(s):  
Iron Sulfide ◽  
Heterotrophic Bacteria ◽  
Negative Impact ◽  
High Water ◽  
Microbiologically Influenced Corrosion ◽  
General Corrosion ◽  
Severe Problem ◽  
Sulfate Reducing ◽  
Corrosion Rates ◽  
High Concentrations

Bacterial proliferation is a severe problem in many oilfield systems, especially in aging systems with high water cuts. Depending on the types of microorganisms present, they can cause microbiologically influenced corrosion (MIC) or biofouling of filters, membranes, and metal surfaces. Common oilfield bacteria include sulfate-reducing bacteria (SRB) that can generate hydrogen sulfide (H2S) and iron sulfide (FeS) as a by-product (iron sulfide can occur in different structural forms), acid producing bacteria that can secrete organic acids that lower the pH within the microenvironment of a biofilm, as well as general heterotrophic bacteria that are often important in biofilm formation and maintenance, amongst others. To prevent corrosion or biofouling caused by these organisms, biocides are commonly added to the production fluids. Some concern has arisen that common oilfield biocides may be inherently corrosive at high end use concentrations and could cause general corrosion in the assets they are protecting from MIC. Accordingly, it is important to understand the risk of MIC, souring, and biofouling versus general corrosion from the biocides themselves. To examine the killing efficiency of oilfield biocides versus their corrosive potential, laboratory work was undertaken with five biocide products including: Tetrakis (hydroxymethyl) phosphonium sulfate (THPS), glutaraldehyde, glutaraldehyde / alkyldimethylbenzyl ammonium chloride (ADBAC) mixture, 5-chloro-2-methyl-4-isothiazolin-3-one/2-methyl-4-isothiazolin-3-one (CMIT/MIT), and a cocodiamine (quaternary amine). Each biocide was evaluated at four different concentrations ranging from 10–100,000 ppm of product. Killing efficiency was determined via bacterial kill studies, while wheelbox and bubble cell testing examined corrosion rates. Corrosion rates varied quite substantially from one biocide to the next, especially at high concentrations. Some biocides were found to be only mildly corrosive even at high dosages, while other biocides were much more corrosive at high concentrations. In general, it was observed that biocide corrosivity is directly related to the dosage of the biocide, with higher dosages correlating with higher corrosion rates. On the other hand, biocides were shown to be effective at killing common oilfield bacteria at relatively low dosages. This data suggests that biocides can be effective at killing bacteria at concentrations that do not cause significant amounts of general corrosion. Additionally, the common practice of batch treating biocides minimizes contact time between the biocide and the metal surface, which is in turn expected to minimize any corrosion that would otherwise be attributed to the biocides themselves. Taken together, this data would suggest that the benefit of biocide treatment to prevent MIC and biofouling substantially outweighs any potentially negative impact on corrosion.

scholarly journals Microbial Diversity of Bacteria Involved in Biomineralization Processes in Mine-Impacted Freshwaters

2021 ◽  
Vol 12 ◽  
Author(s):  
Patrizia Paganin ◽  
Chiara Alisi ◽  
Elisabetta Dore ◽  
Dario Fancello ◽  
Pier Andrea Marras ◽  
...  
Keyword(s):  
Sem Analysis ◽  
Precipitation Process ◽  
Mine Waters ◽  
Sulfate Reducing ◽  
Batch Tests ◽  
High Concentrations ◽  
Geochemical Analyses ◽  
Enriched Cultures ◽  
Next Generation Sequencing Ngs ◽  
Reducing Bacteria

In order to increase the knowledge about geo-bio interactions in extreme metal-polluted mine waters, we combined microbiological, mineralogical, and geochemical analyses to study the indigenous sulfate-reducing bacteria (SRB) involved in the heavy metal (HM) biomineralization processes occurring in Iglesiente and Arburese districts (SW Sardinia, Italy). Anaerobic cultures from sediments of two different mining-affected streams of this regional framework were enriched and analyzed by 16S rRNA next-generation sequencing (NGS) technique, showing sequences closely related to SRB classified in taxa typical of environments with high concentrations of metals (Desulfovibrionaceae, Desulfosporosinus). Nevertheless, the most abundant genera found in our samples did not belong to the traditional SRB groups (i.e., Rahnella, Acinetobacter). The bio-precipitation process mediated by these selected cultures was assessed by anaerobic batch tests performed with polluted river water showing a dramatic (more than 97%) Zn decrease. Scanning electron microscopy (SEM) analysis revealed the occurrence of Zn sulfide with tubular morphology, suggesting a bacteria-mediated bio-precipitation. The inocula represent two distinct communities of microorganisms, each adapted to peculiar environmental conditions. However, both the communities were able to use pollutants in their metabolism and tolerating HMs by detoxification mechanisms. The Zn precipitation mediated by the different enriched cultures suggests that SRB inocula selected in this study have great potentialities for the development of biotechnological techniques to reduce contaminant dispersion and for metal recovery.

Anaerobic Treatment of Viscose Wastewater

1985 ◽  
Vol 17 (1) ◽  
pp. 231-239 ◽  
Author(s):  
H Kroiss ◽  
F Plahl-Wabnegg ◽  
K Svardal
Keyword(s):  
Waste Water ◽  
Treatment Process ◽  
Organic Pollution ◽  
Anaerobic Treatment ◽  
Carbonaceous Matter ◽  
Sulfate Reducing ◽  
Zinc Removal ◽  
Pre Treatment ◽  
High Concentrations ◽  
Reducing Bacteria

The waste water from the viscose production process can be characterized as follows: low to medium strength of biodegradable carbonaceous matter, high concentrations of sulfate, high concentrations of zinc. The treatment process to be presented consists of anaerobic pre-treatment of the neutralized waste water combining the removal of carbonaceous matter with zinc removal by sulfide precipitation. The organic pollution of the waste water is used as a substrate for sulfate reducing bacteria present in the anaerobic reactor. The hydrogen sulfide produced precipitates the zinc as insoluble zinc sulfide. Labscale experiments lasting several months resulted in stable zinc effluent concentrations below 1 mg/l combined with a COD removal of about 40 - 50 %.

scholarly journals Damming Induced Natural Attenuation of Hydrothermal Waters by Runoff Freshwater Dilution and Sediment Biogeochemical Transformations (Sochagota Lake, Colombia)

Water ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 3445
Author(s):  
Gabriel Ricardo Cifuentes ◽  
Rosario Jiménez-Espinosa ◽  
Claudia Patricia Quevedo ◽  
Juan Jiménez-Millán
Keyword(s):  
Natural Attenuation ◽  
Volcanic Area ◽  
Iron Sulfides ◽  
Sulfate Reducing ◽  
High Concentrations ◽  
Biogeochemical Transformations ◽  
Reducing Bacteria ◽  
The Impact ◽  
Basin Area ◽  
Mixed Water

The volcanic area of the Paipa system (Boyacá, Colombia) contains a magmatic heat source and deep fractures that help the flow of hot and highly mineralized waters, which are further combined with cold superficial inputs. This mixed water recharges the Salitre River and downstream feeding Sochagota Lake. The incoming water can contribute to substantial increases in hydrothermal SO42−-Na water in the water of the Salitre River basin area, raising the salinity. An additional hydrogeochemical process occurs in the mix with cold Fe-rich water from alluvial and surficial aquifers. This salinized Fe-rich water feeds the Sochagota Lake, although the impact of freshwaters from rain on the hydrochemistry of the Sochagota Lake is significant. A series of hydrogeochemical, biogeochemical, and mineralogical processes occur inside the lake. The aim of this work was to study the influence of damming in the Sochagota Lake, which acts as a natural attenuation of contaminants such as high concentrations of metals and salty elements coming from the Salitre River. Damming in the Sochagota Lake is considered to be an effective strategy for attenuating highly mineralized waters. The concentrations of dissolved elements were attenuated significantly. Dilution by rainfall runoff and precipitation of iron sulfides mediated by sulfate-reducing bacteria in deposits rich in organic material were the main processes involved in the attenuation of concentrations of SO42−, Fe, As Cu, and Co in the lake water. Furthermore, the K-consuming illitization processes occurring in the sediments could favor the decrease in K and Al.

scholarly journals Metabolic activity of sulfate-reducing bacteria from rodents with colitis

Open Medicine ◽  
2018 ◽  
Vol 13 (1) ◽  
pp. 344-349 ◽  
Author(s):  
Jozef Kováč ◽  
Monika Vítězová ◽  
Ivan Kushkevych
Keyword(s):  
Ulcerative Colitis ◽  
Large Intestine ◽  
Sulfate Reducing Bacteria ◽  
Dissimilatory Sulfate Reduction ◽  
Healthy Human ◽  
Sulfate Reducing ◽  
Anaerobic Microorganisms ◽  
The Difference ◽  
High Concentrations ◽  
Reducing Bacteria

AbstractSulfate-reducing bacteria (SRB) are anaerobic microorganisms, which use sulfate as an electron acceptor in the process of dissimilatory sulfate reduction. The final metabolic product of these anaerobic microorganisms is hydrogen sulfide, which is known as toxic and can lead to damage to epithelial cells of the large intestine at high concentrations. Different genera of SRB are detected in the large intestine of healthy human and animals, and with diseases like Crohn’s disease and ulcerative colitis. SRB isolated from rodents with ulcerative colitis have produced 1.14 (mice) and 1.03 (rats) times more sulfide ions than healthy rodents. The species ofDesulfovibriogenus are the most widespread among all SRB in the intestine. The object of our research was to observe and compare the difference of production of sulfide and reduction of sulfate in intestinal SRB isolated from healthy rodents and rodents with ulcerative colitis.

Behavior of Microbiological Influenced Corrosion of the Ship Plate Steel in Marine Environment

2007 ◽  
Vol 348-349 ◽  
pp. 25-28
Author(s):  
Qing Fen Li ◽  
Chun Hui Li ◽  
Ping Long ◽  
Li Li Xue
Keyword(s):  
Marine Environment ◽  
Corrosion Potential ◽  
Electrochemical Impedance ◽  
Plate Steel ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
X Ray ◽  
Sulfate Reducing ◽  
Sterile Seawater ◽  
Reducing Bacteria

The microbiological influenced corrosion (MIC) behaviors of the ship plate steel directly exposed in different medias (the sterile seawater, the ferrous bacteria solution and the sulfate-reducing bacteria solution) were investigated with electrochemical impedance spectroscopy (EIS), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Corrosion potential, electrochemical impedance and micrographs of specimens under different experimental conditions were obtained. Results show that the FB and SRB in the marine environment affect the corrosion behavior of the ship plate steel greatly. The corrosion process in FB and SRB environment was controlled by both bacteria and corrosion products. The mechanism of MIC is discussed.

A Study on Hydrogen Sulphide as Potential Tracer in Landfill Gas Monitoring

2013 ◽  
Vol 684 ◽  
pp. 189-193
Author(s):  
Tengku Nuraiti Tengku Izhar ◽  
Zaity Syazwani Mohd Odli ◽  
Irnis Azura Zakarya ◽  
Farah Naemah Mohd Saad ◽  
Norlia Mohamad Ibrahim ◽  
...  
Keyword(s):  
Hydrogen Sulphide ◽  
Landfill Gas ◽  
Landfill Site ◽  
Detection Range ◽  
Sulfate Reducing ◽  
Biological Conversion ◽  
The Mean ◽  
High Concentrations ◽  
H2s Emission ◽  
Reducing Bacteria

Municipal solid waste (MSW) landfills are one of the major source of hydrogen sulphide (H2S) which is the offensive odours potentially creating annoyance in adjacent communities. This project focuses on H2S emission from landfills in Perlis, Malaysia. Landfill gas (LFG) samples were collected and analyzed accordance with NIOSH method 6013. The mean concentrations of H2S in Kuala Perlis Landfill and Padang Siding Landfill are 210.68 ppm and 242.85 ppm respectively. High concentrations of H2S may be a concern for employees working on the landfill site. These results indicate that workers should use proper personal protection at landfill when involved in excavation, landfill gas collection, and refuse compaction. The formation of H2S most likely to be contributed by the biological conversion of sulfate from gypsum-rich soils and landfill wastewater treatment sludges by sulfate-reducing bacteria (SRB) which can utilize dissolved sulfate as an electron acceptor. H2S is conveniently detected by hand held analyzer, such Jerome meter, landfill gas analyzer. In the organic range, in the ease of detection range in the dispersion rate within the landfill site, the monitored H2S gas form a very noticeable concentration with the travelling wind direction. It proved that the dispersion rate of H2S are suitable as tracer to detect route of travelling in a certain distance.

Sign in / Sign up

Export Citation Format

Share Document