The Impact of Bacteria of the Genus Bacillus upon the Biodamage/Biodegradation of Some Metals and Extensively Used Petroleum-Based Plastics (original) (raw)
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A STUDY OF MICROBIAL INFLUENCED CORROSION IN OIL AND GAS INDUSTRY
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Microbially Influenced Corrosion and its Control Measures: A Critical Review
Journal of Bio- and Tribo-Corrosion, 2023
Corrosion of materials, induced either by chemicals, or environmental factors or microbials is always a threat to industries. If remain unattended, it will have direct influence on environmental pollution. In recent years lot of work is reported on microbially influenced corrosion which is more prevalent in biotechnology and chemical engineering process industries. However, reports for preventive measures which are taken to mitigate microbially induced corrosion are highly limited. This review is an attempt to consolidate and make a systematic, up to date report on various control techniques that could be implemented to overcome microbially influenced corrosion. The review report opens up by highlighting the causes and concerns related to microbially influenced corrosion, and explains in detail mechanistic aspects of it. It provides in-depth view on attenuating microbially influenced corrosion by using synthetic compounds, green inhibitors, surface modifications, biofilm formation, and nano-particles. The review critically discusses the corrosion inhibition mechanism with merits and limitations of each microbially influenced corrosion inhibitors.
Microbial growth and contamination in aviation fuel storage tanks and aircraft wing tanks cause metal corrosion, plugging of the fuel filter, and increased maintenance costs associated with these problems. This paper reports the microbiologically induced corrosion (MIC) and electrochemical behavior of aluminum alloy (AA 2024) in the presence of hydrocarbon-degrading bacteria Bacillus cereus ACE4 (a Gram-positive bacteria) and Serratia marcescens ACE2 (a Gram-negative bacteria). Electrochemical impedance spectroscopy and metallographic analysis of the metal AA 2024 exposed to a simulated fuel tank environment showed that the bacteria caused pitting corrosion. Scanning electron microscopy-energy-dispersive X-ray spectroscopy analysis (SEM-EDAX), atomic force microscopy (AFM), and Fourier-transform infrared spectroscopy (FTIR) analyses of the aluminum alloy coupons with bacterial biofilm developed after exposure to minimal salt medium confirmed that extracellular polymeric substances accumulate with exposure time and revealed that biofilms are formed as microcolonies, which subsequently cause pitting corrosion. Hydrophobicity of the cell surface was examined using bacterial adhesion to hydrocarbons (BATH) assay. The hydrophobicity and emulsification index of B. cereus ACE4 grown in n-hexadecane containing medium was higher (86% and E 72 85%) than that of S. marcescens ACE2 (60% and E 72 75%), This significant difference may be due to the efficiency of biosurfactant production, which contributes to increase in the cell surface hydrophobicity of the B. cereus ACE4, and enhanced bacterial adhesion on the AA 2024 metal surface. The corrosion damage caused by B. cereus ACE4 is vigorous compared with that from S. marcescens ACE2. This study provides some insight into the MIC of AA 2024 by two hydrocarbon-degrading bacteria in fuel/water mixtures.
Applied Microbiology and Biotechnology, 2008
Microbial colonization of petroleum industry systems takes place through the formation of biofilms, and can result in biodeterioration of the metal surfaces. In a previous study, two oil reservoir Bacillus strains (Bacillus licheniformis T6-5 and Bacillus firmus H 2 O-1) were shown to produce antimicrobial substances (AMS) active against different Bacillus strains and a consortium of sulfatereducing bacteria (SRB) on solid medium. However, neither their ability to form biofilms nor the effect of the AMS on biofilm formation was adequately addressed. Therefore, here, we report that three Bacillus strains (Bacillus pumilus LF4-used as an indicator strain, B. licheniformis T6-5, and B. firmus H 2 O-1), and an oil reservoir SRB consortium (T6lab) were grown as biofilms on glass surfaces. The AMS produced by strains T6-5 and H 2 O-1 prevented the formation of B. pumilus LF4 biofilm and also eliminated pre-established LF4 biofilm. In addition, the presence of AMS produced by H 2 O-1 reduced the viability and attachment of the SRB consortium biofilm by an order of magnitude. Our results suggest that the AMS produced by Bacillus strains T6-5 and H 2 O-1 may have a potential for pipeline-cleaning technologies to inhibit biofilm formation and consequently reduce biocorrosion.
Review on the microbiologically influenced corrosion and the function of biofilms
International Journal of Corrosion and Scale Inhibition
The microbiologically/microbially influenced corrosion (MIC) is a special type of corrosion; in this case the microorganisms by their presence and aggressive metabolites alter the processes on solid surfaces via electrochemical and chemical reactions. When microorganisms are present in most cases the degradation of metals or alloys happens by microbes embedded in biofilms and by their excreted metabolites (e.g. acids), macromolecules (with complexing ability) and by other molecules that can form insoluble precipitates; all these reactions increase the deterioration. The paper summarizes the most important characteristics of the MIC, mainly the so-called biocorrosion of metals and alloys. Not only the chemical and electrochemical processes, but the roles of the corrosion relevant microorganisms in the deteriorating processes, as well as the information about the mechanisms of the MIC worked out in the past and in the very last period are discussed. The most important (aerobic, anaerobic, slime former, acid producer etc.) microorganisms, their nutrient requirements and the formation and role of biofilms are presented, characterized and discussed, as well as the influence of biofilms on the MIC is also demonstrated. The impact of metals on the MIC is also discussed. The history of the research on MIC from its discovery till the 21 th century will demonstrate the enormous work that allowed the understanding of this special type of corrosion as well as its mechanism and the role of the biofilm in MIC. The paper will expose the reactions that go on between the slimy layer (that surrounds the microorganisms even in planktonic form) and the metal surface. The mostly used techniques to visualize what on the surface happens and to measure the change in the current density/corrosion potential and in the corrosion rate due to microbial action are also summarized and in all cases the advantages and disadvantages of all methods are discussed.
Mechanism of Microbial Corrosion: A Review
Journal of chemical, biological and physical sciences, 2016
The role of microorganisms in microbial corrosion is to constantly create surface conditions that favor the maintenance of cathiodic and/ or anodic reactions. There is no generally accepted mechanism of microbiologically influenced corrosion (MIC). Instead various mechanisms of MIC that reflects the variety of physiological activities carried out by different microorganisms have been reported and some have been analyzed better than others. Studies have shown that corrosion of metals in the presence of microorganisms is as a result of the microbial modifications of the environment near the metal surfaces. Microorganisms can influence corrosion processes through their direct actions on anodic and cathodic reactions, formation of biofilms, corrosive media in the form of metabolic by-products and modifications on resistance films on metal surfaces among others.
Journal of Industrial Microbiology & Biotechnology, 2011
The present study enlightens the role of the antagonistic potential of nonpathogenic strain B21 against sulfate-reducing bacteria (SRB) consortium. The inhibitor effects of strain B21 were compared with those of the chemical biocide tetrakishydroxymethylphosphonium sulfate (THPS), generally used in the petroleum industry. The biological inhibitor exhibited much better and effective performance. Growth of SRB in coculture with bacteria strain B21 antagonist exhibited decline in SRB growth, reduction in production of sulfides, with consumption of sulfate. The observed effect seems more important in comparison with the effect caused by the tested biocide (THPS). Strain B21, a dominant facultative aerobic species, has salt growth requirement always above 5% (w/v) salts with optimal concentration of 10-15%. Phylogenetic analysis based on partial 16S rRNA gene sequences showed that strain B21 is a member of the genus Bacillus, being most closely related to Bacillus qingdaonensis DQ115802 (94.0% sequence similarity), Bacillus aidingensis DQ504377 (94.0%), and Bacillus salarius AY667494 (92.2%). Comparative analysis of partial 16S rRNA gene sequence data plus physiological, biochemical, and phenotypic features of the novel isolate and related species of Bacillus indicated that strain B21 may represent a novel species within the genus Bacillus, named Bacillus sp. (EMBL, FR671419). The results of this study indicate the application potential of Bacillus strain B21 as a biocontrol agent to fight corrosion in the oil industry.
The importance of live biofilms in corrosion protection
Corrosion Science, 2005
As observed before, Al 2024 was passive in artificial seawater (AS) in the presence of a protective biofilm of Bacillus subtilis WB600. When antibiotics were added to the AS to kill the bacteria in the biofilm, pitting occurred within a few hours as indicated by characteristic changes in the impedance spectra. The corrosion potential E corr decreased at the same time to values observed in sterile AS. Addition of the antibiotics to sterile AS had no effect on corrosion behavior.
Biocidal effect of cathodic protection on bacterial viability in biofilm attached to carbon steel
Biotechnology and Bioengineering, 2007
Biofilm formed on carbon steel by various species of bacterial cells causes serious problems such as corrosion of steel, choking of flow in the pipe, deterioration of the heat-transfer efficiency, and so on. Cathodic protection is known to be a reliable method for protecting carbon steel from corrosion. However, the initial attachment of bacteria to the surface and the effects of cathodic protection on bacterial viability in the biofilm have not been clarified. In this study, cathodic protection was applied to an artificial biofilm containing Pseudomonas aeruginosa (PAO1), a biofilm constituent, on carbon steel. The aims of this study were to evaluate the inhibition effect of cathodic protection on biofilm formation and to reveal the inhibition mechanisms. The viability of PAO1 in artificial biofilm of 5 mm thickness on cathodically protected steel decreased to 1% of the initial cell concentration. Analysis of pH distribution in the artificial biofilm by pH microelectrode revealed that pH in proximity to carbon steel increased to approximately 11 after cathodic protection for 5 h. Moreover, 99% of region in the artificial biofilm was under the pH conditions of over nine. A simulation of pH profile was shown to correspond to experimental values. These results indicate cells in the artificial biofilm were killed or damaged by cathodic protection due to pH increase.