Waste rapeseed oil is a useful substrate for polyhydroxyalkanoates (PHA) production employing Cupriavidus necator H16. In fed-batch mode, we obtained biomass and PHA yields of 138 and 105 g l -1 , respectively. Yield coefficient and volumetric productivity were 0.83 g PHA per g oil and 1.46 g l -1 h -1 , respectively. Propanol at 1% (v/v) enhanced both PHA and biomass formation significantly and, furthermore, resulted in incorporation of 3-hydroxyvalerate units into PHA structure. Thus, propanol can be used as an effective precursor of 3-hydroxyvalarete for production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) copolymer. During the fed-batch cultivation, propanol concentration was maintained at 1% which resulted in 8% content of 3-hydroxyvalerate in copolymer.

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Summary: Biodegradable thermosensitive triblock copolymers based on poly(ethylene glycol) and poly(lactic‐co‐glycolic acid) (PLGA‐PEG‐PLGA) prepared via ring opening polymerization were modified by itaconic anhydride (ITA), which gives copolymer both reactive double bonds and functional carboxylic acid groups essential for the reaction with biological active material. Functionalization conditions comprising ITA purification, temperature, time and presence of solvent were optimized with the respect to amount of end‐capped ITA. Maximum of 76.6 mol. % of bonded ITA were reached via “one pot” reaction in a bulk at 110 °C after 1.5 h. ITA functionalization thermally stabilized the original copolymer by increasing the initial degradation temperature Td from 284 °C to 294 °C and changing the negative glass transition temperature (Tg = ‐1.8 °C) to positive one up to 2.4 °C. The novel functionalized macromonomer can be cross‐linked either chemically or physically in order to produce new functionalized hydrogel network applicable as biomedical material in tissue engineering.

Poly(3-hydroxybutyrate) (PHB) is a polyester belonging to the family of polyhydroxyalkanoates, which accumulate in a wide variety of bacterial strains. PHB appears to be a biodegradable alternative to traditional petrochemical polymers such as polypropylene and polyethylene. In this work, we tested direct conversion of cheap waste cheese whey into PHB employing the bacterial strain Bacillus megaterium CCM 2037. Optimization of medium composition improved PHB yields about 50 fold (biomass and PHB yields 2.82 and 1.05 g l −1 , respectively) as compared to none-optimized whey. Furthermore, PHB yields were improved by about 40% by introducing 1% ethanol into the medium at the beginning of the stationary phase of growth (biomass 2.87 g l −1 , PHB 1.48 g l −1 ). According to the results of experiments carried out in Erlenmeyer flasks, B. megaterium CCM 2037 can be considered a candidate for direct PHB production from waste cheese whey. Nevertheless, experiments in laboratory-scale and semi-productive fermentors are needed to test performance under high cell density cultivation.

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