Abstract:
The integration of nanotechnology into environmental biotechnology offers new strategies for enhancing the performance of anaerobic processes. This study investigates the application of electrospun nanofiber biomass carriers as structured supports for microbial colonisation in a laboratory anaerobic bioreactor.
Three polymer-based nanofiber materials were evaluated as biomass carriers: polyurethane (PUR), polyacrylonitrile (PAN), and polyvinylidene fluoride (PVDF), selected for their distinct surface properties. All three types were prepared by electrospinning directly onto a supporting polyester yarn, which served as a structural scaffold from the point of fabrication.
The application of nanofiber carriers was assessed by submerging them in a laboratory anaerobic bioreactor for 52 days. The bioreactor was inoculated with a defined five-strain consortium (Methanobacterium formicicum, Clostridium acetobutylicum, Lactiplantibacillus paraplantarum, Paracoccus denitrificans, and Desulfovibrio vulgaris) and operated for 235 days. Microbial community dynamics were monitored by quantitative PCR (qPCR) with strain-specific markers and next-generation sequencing (NGS) targeting the 16S rRNA gene.
All five strains were detectable within 48 hours of bioreactor startup. Over the course of the experiment, C. acetobutylicum was lost from suspension by day 25 and P. denitrificans by day 119, consistent with competitive exclusion. D. vulgaris and M. formicicum persisted throughout, with M. formicicum abundance increasing progressively from day 78. NGS revealed gradual enrichment of syntrophic genera, including Syntrophomonas and Tepidimicrobium. The PVDF-based carrier showed the highest total microbial biomass and the greatest retention of inoculated strains among the three variants, indicating that the nanofiber polymer has a material-dependent influence on biofilm community structure.
These findings demonstrate that electrospun nanofiber carriers shape the composition and long-term stability of anaerobic microbial consortia, supporting their potential as a nanotechnological platform for biogas production and wastewater treatment.
