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Biodegradation of polyethylene film in the presence of fungi and in soil

100%

Pajak J., Nowak B., Labuzek S.

Biotechnologia

2003

issue 4

214-227

The aim of the investigation was the biodegradation of low-density polyethylene (LDPE) film modified with Bionolle?. The samples in the form of composite films were prepared by homogenization and extrusion. The biodegradation process was performed in the laboratory scale or under environmental conditions. The examined films were placed into different media and incubated in the presence of fungi Aspergillus niger, Penicillium funiculosum and mixed fungi inoculum. Any changes in the various properties of the films after biodegradation were monitored by weight loss, optical and scanning electron microscopy and FTIR spectroscopy. The results of the study have proved that fungal growth on the polymer samples containing low amount of polyester depends on the presence of nutrients in media. Sucrose inhibited polymer disintegration more strongly than nutrient broth. FTIR analysis revealed that filamentous fungi biodegraded not only polyester, but also polyethylene. On the contrary, LDPE incubated in soil did not exhibit any chemical changes. This highly hydrophobic polymer was more susceptible to biodegradation only in the presence of Bionolle?.

Enzyme ? mediated polymer synthesis

88%

Rokicki G.

Biotechnologia

2005

issue 2

103-124

Enzyme ? mediated polymer synthesis in non-natural environments has significantly expanded in scope and impact over the past 10 years. This review focuses on a rapidly expanding research activity where in vitro enzyme catalysis is used for the synthesis of polyesters, polycarbonates, polyphenols, vinyl polymers, as well as natural and artificial oligosaccharides like cellulose, amylose, xylan, and chitin. The inclination to use enzymes for polymer synthesis has been fuelled by a desire to carry out these reactions in the absence of heavy metal-based catalysts, under mild conditions and with high selectivity. The aspects of this work that include enzyme-catalyzed step-growth polycondensation, chain-growth ring-opening polymerizations, oxidation polymerization and corresponding transesterification of macromolecular substrates are discussed. The polymerization utilizes mainly hydrolases and oxidoreductases as catalysts. Characteristic features of enzymatic polymerizations are also discussed.

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2 Biotechnologia

1 2005

1 2003

1 Labuzek S.

1 Nowak B.

1 Pajak J.

1 Rokicki G.

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Biodegradation of polyethylene film in the presence of fungi and in soil

Enzyme ? mediated polymer synthesis