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Biodegradation of polycyclic aromatic hydrocarbons (PAHs) by fungal enzymes: A review 总被引:1,自引:0,他引:1
Tayssir Kadri Tarek Rouissi Satinder Kaur Brar Maximiliano Cledon Saurabhjyoti Sarm Mausam Verma 《环境科学学报(英文版)》2017,29(1):52-74
Polycyclic aromatic hydrocarbons (PAHs) are a large group of chemicals. They represent an
important concern due to their widespread distribution in the environment, their
resistance to biodegradation, their potential to bioaccumulate and their harmful effects.
Several pilot treatments have been implemented to prevent economic consequences and
deterioration of soil and water quality. As a promising option, fungal enzymes are regarded
as a powerful choice for degradation of PAHs. Phanerochaete chrysosporium, Pleurotus ostreatus
and Bjerkandera adusta are most commonly used for the degradation of such compounds
due to their production of ligninolytic enzymes such as lignin peroxidase, manganese
peroxidase and laccase. The rate of biodegradation depends on many culture conditions,
such as temperature, oxygen, accessibility of nutrients and agitated or shallow culture.
Moreover, the addition of biosurfactants can strongly modify the enzyme activity. The removal of PAHs is dependent on the ionization potential. The study of the kinetics is not completely comprehended, and it becomes morem hallenging when fungi are applied for bioremediation. Degradation studies in soil are much more complicated than liquid cultures because of the heterogeneity of soil, thus, many factors should be considered when studying soil bioremediation, such as desorption and bioavailability of PAHs. Different degradation pathways can be suggested. The peroxidases are heme-containing enzymes having common catalytic cycles. One molecule of hydrogen peroxide oxidizes the resting enzyme withdrawing two electrons. Subsequently, the peroxidase is reduced back in two steps of one electron oxidation. Laccases are copper-containing oxidases. They reduce molecular oxygen to water and oxidize phenolic compounds. 相似文献
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Meeta Lavani Priyangshu M. Sarm Ajoy K. Man Simrita Cheem Banwari La 《环境科学学报(英文版)》2011,23(8):1394-1402
We compared the efficacy of a natural biocide with four chemical tetrakishydroxymethyl phosphonium sulfonate, benzyl trimethyl
ammonium chloride, and formaldehyde, glutaraldehyde, to control microbial induced corrosion in oil pipelines. The efficacy of biocides
were monitored against Desulfovibrio vulgaris and Desulfovibrio gigas in experimental pipes by measuring cell counts, H2S production,
Fe(II) production, production of extracellular polymeric substances and structure of biofilm. The treatment with cow urine had minimum
planktonic cell counts of 3 102 CFU/mL as well as biofilm cell counts of 9 101 CFU/mL as compared with tetrakishydroxyl methyl
phosphonium sulfonate, benzyl trimethyl ammonium chloride, formaldehyde and glutaraldehyde. Sulfide production was the lowest
with cow urine (0.08 mmol/L), followed by tetrakishydroxymethyl phosphonium sulfonate 0.72 mmol/L. On day 90 of treatment,
Fe(II) production was also found to be the lowest with cow urine. The scanning electron microscopic studies indicated that the biofilm
bacteria were killed by cow urine. These results demonstrate the cow urine mediated control of microbially induced corrosion, and this
is indicative of its potential as a viable substitute of toxic biocides. To the best of our knowledge, this seems to be the first report which
screens possible biocidal activity by cow urine as compared to the most common biocides which oil industry is currently using. 相似文献
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