Micro-organisms biodegradation

Keywords Micro-organisms, biodegradation, bioprecipitation, biostimulation, bioaugmentation, electron donor, electron acceptor, injection. 

Van Veen, J. A., and Kuikman, P. J. (1990). Soil structural aspects of decomposition of organic matter by micro-organisms. Biodegradation 11(3), 213-233. 

Soil burial is widely used as the method of testing susceptibility to degradation. It closely mimics the conditions of waste disposal used for plastics but it is often difficult to reproduce results obtained because of absence of control over either the climate at the test site or the variety of micro-organisms involved in the degradation. Soil burial is thus used to provide qualitative indications of biodegradability, with more controlled laboratory work with cultured micro-organisms being used to obtain more quantitative detail. 

The ability of a degradable plastic to decay depends on the structure of its polymer chain. Biodegradable plastics are often manufactured from natural polymers, such as cornstarch and wheat gluten. Micro-organisms in the soil can break down these natural polymers. Ideally, a biodegradable plastic would break down completely into carbon dioxide, water, and biomass within six months, just like a natural material. 

Biodegradable materials are destroyed by micro-organisms into short molecules that can be assimilated by plants and other living organisms... 

All these pol3nners were tested for biodegradation in the presence of soil micro-organisms. A conventional sandy loam was employed. Schematic representation of the degradation apparatus was shown in Figure II. 

Soil biodegradation tests were done by taking a sandy loam as the source of the soil micro-organisms. All polymer samples were sieved through ASTM sieves and all the samples except poly-e-caprolactone, had a particle diameter between 90 and 53 pm, Poly-e-caprolactone sample was prepared dissolving a commercially... 

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