In the originally published version of this article, Daniel Geiszler's last name was misspelled. This error has now been corrected in the article online.

The pine stems were cut from three different polluted environments – Ist trees degradation degree (weak pollution), IInd trees degradation degree (strong pollution) and IIIrd trees degradation degree (connected with very strong pollution). On the basis of obtained results it was stated that environmental pollution caused changes in late wood participation, as well as distribution of cellulose on the stem cross- and longitudinal section. It also changed cellulose content in bark from the butt-end section, which was about 26% regardless the degradation degree. The environmental pollution caused also an increase of viscometric average polymerization degree of cellulose in heartwood in relation to heartwood adjacent sapwood and sapwood from butt-end section. Regardless the degradation degree, cellulose polymerization degree in heartwood adjacent sapwood from the middle part of the stem was higher in comparison to sapwood and heartwood. Moreover, the environmental pollution caused the increase of viscometric average polymerization degree of cellulose in bark. The polymerization degree of cellulose in bark from the butt-end section of IIIrd degradation degree stems was 22% and 23% higher in comparison to the Ist and IInd degradation degree.

Summary The effects of κ‐carrageenan and its hydrolysates on modification of the freezing process and also on inhibition of excessive recrystallisation of ice in sucrose solutions during storage were compared. Acid hydrolysis of κ‐carrageenan was carried out using sulphuric (H2SO4) and hydrochloric acid (HCl). Most effective in the hydrolysis process turned out to be H2SO4, which degraded κ‐carrageenan to a molecular mass of around 3 × 106 Da, after 1.5 h of hydrolysis. Addition of 0.005% of the new poligeenan (degraded carrageenan), to a sucrose solution (30%), frozen at −20 °C, caused a nearly 50% reduction in the phase‐change stages, and consequently, the total time of freezing was shorter. Significant retardation of recrystallisation was observed for both types of poligeenan, but a stronger effect was observed for the oligosaccharides obtained after HCl hydrolysis, and after 96 h of storage at −8 °C, the equivalent diameter of ice crystals was not greater than 11 μm.

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The purpose of the paper is designation of the changes in the structure of cellulose after the methane fermentation process of Miscanthus and Sorghum harvested during the growing season and afterwards. The percentage and structure of cellulose before and after fermentation were studied. Investigations into changes of the cellulose structure were conducted by the SEC, FT-IR and XRD methods. The average percentage of cellulose after the growing season for Miscanthus varieties was higher and for Sorghum varieties was lower. As a result of the fermentation, the percentage of cellulose for both investigated species harvested in two growth seasons was lower. The degree of polymerisation for the plants harvested after the growing season was lower for the most feedstock. As a result of the fermentation process, the degree of polymerization increased for each of the investigated feedstock. However, crystallinity of cellulose remained at the same level for Miscanthus and decreased for Sorghum. It was shown that changes were different in the cellulose structure of the compared species.