Investigation of the degradation mechanisms of PHB and HDPE in an industrial composting facility

Bioplastics often do not end up in composting facilities, due to hesitations over the timeframe of biodegradation of bioplastics and the impact they may have on the final compost product. Therefore, many bioplastics end up in landfill. Whilst studies have looked at the biodegradability of bioplastics in compost in a lab setting, few have investigated this in an industrial composting setting or investigated the impact of bioplastic degradation on the microbiome of the compost. Therefore, this study will investigate polyhydroxy butyrate (PHB) biodegradation and its interactions with the industrial composting environment. DNA will be extracted from the biofilm on the PHB bioplastic and a petro-plastic (high-density polyethylene (HDPE)) and from compost near the site of the bioplastic and far away from the site of the bioplastic. It will then be analysed using PACBIO sequencing. Physical signs of biodegradation will also be investigated using techniques such as: scanning electron microscopy, thermogravimetric analysis and differential scanning calorimetry.