Comparison of yields and properties of microbial polyhydroxyalkanoates generated from waste glycerol based substrates

• Published in: International journal of biological macromolecules Vol. 112; pp. 273 - 283
• Main Authors: Ntaikou, Ioanna, Koumelis, Ioannis, Tsitsilianis, Constantinos, Parthenios, John, Lyberatos, Gerasimos
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01-06-2018
• Subjects: Polyhydroxyalkanoates; Thermal properties, mechanical properties; Waste glycerol; Polyhydroxyalkanoates; Thermal properties, mechanical properties; Waste glycerol
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2018.01.175

The accumulation efficiency and the properties of polyhydroxyalkanoates (PHAs) produced from acidified waste glycerol (AWG) and its derivatives via an enriched microbial consortium derived from soil, were investigated in this study. AWG consisted mainly from short chain fatty acids, 1,3 propanediol and residual glycerol, which were also evaluated individually as substrates. Accumulation capacity and yields were estimated after solvent extraction and purification and PHAs were further analyzed in terms of their chemical structure, thermal properties, molecular masses and mechanical properties. The lowest accumulation capacity was noticed for non-acidified waste glycerol as carbon source which led to the generation of P(3HB), whereas for the other carbon sources co-polymers of 3HB with 3HV or 3HHx were produced. Average molecular mass weights were quite high in all cases reaching ~1.8×106Da. The thermal properties and the mechanical behavior of PHAs were shown to be highly affected by their monomeric composition, whereas it was also concluded that DSC and DMA results were in good agreement.
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•Acidified waste glycerol and its derivatives were bioconverted to PHAs by MMCs.•PHAs produced consisted of 3HB and either 3HV or 3HHx units.•The maximum accumulation capacity of the MMC was 40% (w/w CDW) in the case of AWG.•DSC and DMA results were in good agreement.•The mechanical behavior of PHAs was highly affected by their monomeric composition.