Plastic is a common term used to include all sorts
of polythene (polyethylene) and polyvinyl chloride
(PCV) materials. These materials have an advantage
in being cost effective, light weight, flexible and
in their ability to be molded according to the user
and producer made the plastics ubiquitous. But the
problem which neutralizes all these attributes, in
their recalcitrance, i.e., they cannot be degraded
easily by nature.
The main effect of land pollution by plastics is
the blockage of rain water from getting underground,
thus, reducing ground water level. These plastic wastes
can be disposed off by either recycling or incineration.
Recycling is not widely used now because of economics.
Even incineration causes air pollution, as combustion
of plastic in mass will release highly toxic organic
compounds into the air. Vinyl chloride and acrylonirrile
are classified as environmental carcinogens while
some whiteners and toxicants.
Recent research found that most of the constituents
of plastics can be microbially degraded and the film
plastics can be treated by microbial systems. Acrylonirrile
fibers are attacked by species of Aspergillus,
Penicillium, Stachybotrys, and Nigrespora . Polycaprolactone
is degraded by Aspergillus niger , Aspergillus
flavus, Penicillium fumiculosum, Chactomium globosum
and Pullularia pullulans.
Fungi like Aspergillus fumigatus, Chactomium
thermophile, Humicola lanuginose, Mucorpusillus
and Torula thermophile can degrade
plastic polymer of thermophilic temperature of 48
° C. Strains like Penicillium fumiculosum
and Candida lipolytica degrade plastics.
Using polymerized vinyl acetate or ethylene copolymer,
dissolved out the substrate by depolymerisation. Pullularia
pullulans can degrade polycarpolactone and other
aliphatic polyesters. N-alkenes, alkenes and other
aliphatic hydrocarbons are readily utilized by yeasts
and fungi. Since a wide variety of fungi grow and
degrade plastics and their polymers, only they have
to be upgraded.