Polystyrene is considered stable to biological degradation. Lantinus tigrinus isolated from wood sample produced esterase in growth medium under normal conditions. However, acidic medium, 37°C temperature, presence of tween 80; and urea and yeast extract in mineral salt medium enhance the production of esterase and specific activity. Purified esterase was active at broad pH range and 45°C. FTIR analysis confirmed that esterase produced by Lantinus tigrinus effectively degraded polystyrene film and broke macromolecules down to non-toxic molecules. This study concludes that the presence of Lantinus tigrinus at dumping sites can be exploited for waste management containing high molecular weight synthetic polymers.
At Królmet Iron Foundry some research and experimental studies have been carried out to develop technical and technological guidelines for the manufacture of pilot castings for machinery applications. The castings should be characterised by good mechanical properties, specially by good hardnesss, high abrasion wear resistance and impact resistance. Pilot castings have been made by lost foam technology on a modern casting installation. The output of the research and experimental work was designing and making of pattern tooling, determination of technical and technological parameters of the process, and making a batch of pilot castings. The produced castings had the required utilisation parameters.
Attempts to obtain a micro-dispersion-based formulation insecticide were made. An aqueous micro-suspension of polystyrene had been used to trap pyrethroid lambda-cyhalothrin. A method of introducing the active substance into the polymer was developed. The biological efficiency of micro-emulsion of lambda-cyhalothrin with polystyrene was investigated.
The present study investigated the ability of sub MICs of cefotaxime, imipenem and ciprofloxacin to interfere with adhesion of E. coli strains to polystyrene (selected polymer used in studies on microorganisms’ adhesion). It was observed that cefotaxime and imipenem at ½ and ¼ MICs decreased the adherence of E. coli strains to polystyrene significantly. ½, ¼ and ⅛ MICs of ciprofloxacin generally decreased the adhesive properties of E. coli strains, but two E. coli strains showed a noticeable enhancement of adhesion after incubation at sub MICs of this antibiotic.