Hydrocarbons biodegradation

In a similar manner, expression of biodegradable hydrocarbons as a ratio to high-molecular-weight polynuclear aromatic hydrocarbons should have potential for fingerprinting purposes. The failure of some attempts to use PAHs for this purpose arises from the poor choice of molecules for comparison. Low-molecular-weight PAHs such as naphthalene or phenanthrene are often selected because of their abundance and relative ease of measurement, but these molecules are also the most prone to biodegradation as well as other forms of attenuation (Sadler and Connell, 2002). 

The microbes will not survive an excessive amount of bleach or any bacteride, pH above 11 or below 4, or temperature higher than 120°F. This technology cannot handle metals and is only applicable to biodegradable hydrocarbon contaminants. 

Low gas fluxes result in mineralization, such as carbonate mounds, cones, and chimneys, with very localized and poorly developed chemo-synthetic communities, and highly biodegraded hydrocarbons. 

Localized Bacterial Mats, Lucinid Vesycomyid Clays Nonbiodegraded - Slightly Biodegraded Hydrocarbons... 

Pogonophoran Tube Worms, Bathymodiolid Mussels, Lucinid Clams) Moderately Biodegraded Hydrocarbons... 

Very Localized and Poorly Developed Chemosynthetic Communities Highly Biodegraded Hydrocarbons... 

This term refers to crude oils, distillation, and cracking products (coal tar) and emulsions of these substances. All of these substances are microbially biodegradable. Hydrocarbons are conducive to microorganisms, and microbial growth causes damage to materials such as fuel tanks and pipelines (51). 

There are many existing and potential industrial applications of extremophilic enzymes (see Table 2), which take advantage of their capacity to thrive in harsh conditions, relative to their mesophilic (ie, function under moderate conditions) counterparts. For example, the detergent industry makes extensive use of alkaline-stable proteases, accounting for approximately 30% of global enzyme production (27). Enzymes from extremophiles have been used for bioremediation heavy metals and radionuclides from wastewaters (28), as well as for biodegrading hydrocarbons in polar soils (29). It is likely that extremophilic enzymes will find wide use in applications that strategically use their intrinsic robustness as biocatalysts. 

Cl to C4 - Few species can utilize this group (require special enzymes). C5 to Cg - microbial membranes do not tolerate solvent character. Limited utilization by some bacteria and fungi. Not utilized by yeast. Cio to C22 - Most readily biodegradable hydrocarbons. > C22 - low water solubility, generally solids. Utilized less than straight chain alkanes. CH3 branching in the 3-position — resists j8-oxidation Utilized less than alkanes. More toxic than alkanes. 

Biodegradable Hydrocarbon Polymers AN Environmentally Acceptable Solution TO Plastics Waste and Litter... 

Biodegradable Hydrocarbon Polymers an Environmentally Acceptable Solution... 223... 

Biodegradable Hydrocarbon Polymers an Environmentally Acceptable Solution... 231 Table 2 Time scale for the bioassimilation of aged oxo-biodegradable polyethylene [6]... 

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