1. Microbial desulfurization of ground tire rubber (GTR): Characterization of microbial communities and rheological and mechanical properties of GTR and natural rubber composites (GTR/NR)
- Author
-
Elena Collina, Andrea Franzetti, Ivan Mangili, Giuseppina Bestetti, Paola Caracino, Marina Lasagni, Danilo Porro, Paola Branduardi, Valeria Tatangelo, Manuela Anzano, Riccardo Posteri, Tatangelo, V, Mangili, I, Caracino, P, Bestetti, G, Collina, E, Anzano, M, Branduardi, P, Posteri, R, Porro, D, Lasagni, M, and Franzetti, A
- Subjects
Polymers and Plastics ,02 engineering and technology ,010402 general chemistry ,medicine.disease_cause ,complex mixtures ,01 natural sciences ,Microbial desulfurization Ground tire rubber (GTR) Mechanical properties ARISA NGS ,Gordonia desulfuricans ,Natural rubber ,Materials Chemistry ,medicine ,Bioreactor ,Food science ,biology ,Chemistry ,technology, industry, and agriculture ,Ribosomal RNA ,equipment and supplies ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,biology.organism_classification ,16S ribosomal RNA ,0104 chemical sciences ,Flue-gas desulfurization ,Mechanics of Materials ,visual_art ,visual_art.visual_art_medium ,0210 nano-technology ,Rhodococcus ,Bacteria - Abstract
This study focused on the characterization of microbial communities during the desulfurization of ground tire rubber (GTR) by two bacterial strains i) Gordonia desulfuricans DSM 44462T, and ii) Rhodococcus sp. AF21875. Automated ribosomal inter-genic spacer analysis (ARISA), and high throughput sequencing of 16S rRNA gene amplicons were used to analyze samples collected from the bioreactors over time to detect the persistence of the inoculated bacteria within the autochthonous communities, and to compare communities in the bioreactors. Furthermore, the abundance of total bacteria (16S rRNA gene) and biodesulfurization potential (dszA) were estimated using qPCR, in the bioreactors and on GTR before the treatment. ARISA showed that G. desulfuricans DSM 44462T was able to persist, while there is no clear evidence of Rhodococcus sp. AF21875 persistence into the bioreactor due to the presence of matching ARISA fragments in the untreated GTR. In both bioreactors, a high abundance of genus Gordonia and Rhodococcus was observed, with an increase of dszA copy numbers over time. Vulcanizates containing biodesulfurized GTRs showed better mechanical and rheological properties than an untreated GTR vulcanizate and even comparable with a natural rubber reference.
- Published
- 2019
- Full Text
- View/download PDF