Several steps occur in the plastic biodegradation process and could be identified by specific terminology:

-Bio-deterioration defines the action of microbial communities and other decomposer organisms responsible for the physical and chemical deterioration that resulted in a superficial degradation that modifies the mechanical, physical and chemical properties of the plastic.

-Bio-fragmentation refers to the catalytic actions that cleave polymeric plastics into oligomers, dimers or monomers by ecto-enzymes or free-radicals secreted by microorganisms.

-Assimilation characterizes to the integration of molecules transported in the cytoplasm in the microbial metabolism.

-Mineralisation refers to the complete degradation of molecules that resulted in the excretion of completely oxidized metabolites (CO2, N2, CH4, H2O)

the microbial communities that developed on plastic may be highly diverse and the development of a biofilm may release acid compounds such as nitrous acid (e.g. Nitrosomonas spp.), nitric acid (e.g. Nitrobacter spp.) or sulphuric acid (e.g. Thiobacillus spp.) by chemolithotrophic bacteria .

Organic acids such as oxalic, citric, fumaric, gluconic, glutaric, glyoxalic, oxalic and oxaloacetic acids may also be released by chemoorganotrophic communities. The pH inside the pores is then modified, resulting in a progressive degradation that changes the microstructure of the plastic matrix .

hi, check the protocol of ASTM G21-90 with fungi

Dear Aftab,

there are some publications on plastics-degrading bacteria. Species comprise Bacilli, Pseudomonas spp and Enterobacter. Two examples:

http://onlinelibrary.wiley.com/doi/10.1111/1751-7915.12312/full

http://pubs.acs.org/doi/abs/10.1021/es504038a?source=cen

http://science.sciencemag.org/content/351/6278/1196

M