One of the best sterilization methods for chemically unstable drugs, such as carbapenems, is irradiation. The chemical and physical properties of radiosterilized imipenem and cilastatin were analyzed using spectrophotometric and chromatographic methods. Unstable free radicals were presented in samples after irradiation; their mean lifetime was 142±64 h. The antibacterial activity of cefozopran hydrochloride irradiated with a dose of 25 kGy changed for Klebsiella pneumoniae and Escherichia coli. Imipenem and cilastatin in the solid state are not resistant to radiation sterilization; therefore, this method cannot be used for sterilization of this compound.
The influence of ionising radiation on physicochemical properties of doripenem in solid state was studied. No changes for doripenem irradiated with a dose of 25 kGy, required to attain sterility, was observed by FT-IR and chromatographic methods, although the presence of free radicals (7.7*1017 radicals/g) was detected by EPR. The antibacterial activity of doripenem irradiated with a dose of 25 kGy was unchanged. Solid doripenem has proven to be very stable on irradiation, and irradiation has been found to be a suitable method for its sterilization.
Four new mixed complexes of Cu(II) with tpmc and bridge bound N,S or N,O ligands of the general formula. Elemental and thermal analyses, conductometric and magnetic measurements, electronic, IR and mass spectrscopy have been emplyed.
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The study was conducted on an experiment established in the area of the former Sulphur Mine “Jeziorko.” The remediation was applied to a soil-less formation with particle size distribution of weakly loamy sand, strongly acidified and with bad sorptive properties (Corg. - 2.0 g kg−1; pHKCl - 4.3; T - 7.0 cmol(+) kg−1). In the particular treatments of the experiment the following were applied to the soil-less formation: flotation lime and NPK; lime and sewage sludge; sewage sludge; mineral wool (5 cm 50 cm−1), lime and NPK; mineral wool (5 cm 50 cm−1), lime and sewage sludge; mineral wool (500 m3 ha−1), lime and NPK; mineral wool (500 m3 ha−1), lime and sewage sludge. Plots prepared in that manner were then sown with a mix of grasses. The control was the soil with no amendments. The analyses of the soil material comprised assays of the numbers of particular groups of bacteria and fungi, and of their biochemical and enzymatic activities. The study revealed that all the wastes applied for the remediation caused an increase in the numbers of the bacterial groups studied (copiotrophic, oligotrophic, cellulolytic, lipolytic), as well as in the respiration activity and rate of mineralisation of cellulose. That effect was the most pronounced in the case of sewage sludge. In treatments in which sewage sludge was applied, an increase was also observed in the numbers of the studied fungi (fungi on Martin medium, cellulolytic fungi, lipolytic fungi) and in lipase activity. Whereas, the application of the remaining wastes resulted in a slight decrease in the numbers of the fungal groups under analysis. Comparing the mean annual values of the analysed biological, physical, chemical and physicochemical properties it was found that the biological properties were as sensitive, and in the case of certain tests (numbers of cellulolytic and lipolytic bacteria, rate of cellulose mineralisation) even more sensitive indicators of positive changes taking place in the remediated soil.
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