Screening for Methane Utilizing Mixed Communities with High Polyhydroxybutyrate (PHB) Production Capacity Using Different Design Approaches.

With the adverse environmental ramifications of the use of petroleum-based plastic outweighing the challenges facing the industrialization of bioplastics, polyhydroxyalkanoate (PHA) biopolymer has gained broad interest in recent years. Thus, an efficient approach for maximizing polyhydroxybutyrate (PHB) polymer production in methanotrophic bacteria has been developed using the methane gas produced in the anaerobic digestion process in wastewater treatment plants (WWTPS) as a carbon substrate and an electron donor. A comparison study was conducted between two experimental setups using two different recycling strategies, namely new and conventional setups.

Enhancement of the cultivation process conditions of mixed culture methanotrophic Proteobacteria phylum enriched from waste activated sludge as the first step for value added recovery process.

Methanotrophs are of great interest due to their distinguish ability of recovering value-added commodities such as methanol and lipids while mitigating methane. The enhancement of methanotrophs cultivation process conditions is a pivotal step to develop a feasible methanotrophic bioreactor. In this study, multiple batch tests have been performed to evaluate the aqueous growth medium elements including nitrogen, copper, and biomass density and the gaseous headspace composition influence on methanotrophs activity and the associated microbial community.

Development of Methane-Utilizing Mixed Cultures for the Production of Polyhydroxyalkanoates (PHAs) from Anaerobic Digester Sludge.

The fundamental components required for scaling up the production of biogas-based biopolymers can be provided through a single process, that is, anaerobic digestion (AD). In this research, the possibility of enriching methane-utilizing mixed cultures from the AD process was explored as well as their capability to accumulate polyhydroxyalkanoates (PHAs). For almost 70 days of operation in a fed-batch cyclic mode, the specific growth rate was 0.

Influence of biomass density and food to microorganisms ratio on the mixed culture type I methanotrophs enriched from activated sludge.

Methanotrophic based process can be the remedy to offset the wastewater treatment facilities increasing energy requirements due to methanotroph's unique ability to integrate methane assimilation with multiple biotechnological applications like biological nitrogen removal and methanol production. Regardless of the methanotrophic process end product, the challenge to maintain stable microbial growth in the methanotrophs cultivation bioreactor at higher cell densities is one of the major obstacles facing the process upscaling. Therefore, a series of consecutive batch tests were performed to attentively investigate the biomass density influence on type I methanotrophs bacterial growth.