Bacterial communities of tyre monofill sites: growth on tyre shreds and leachate

Abstract

Aims: To investigate bacterial communities of tyre monofill sites, colonization of tyre material by bacteria and the effect of tyre leachate on bacteria. Methods and Results: Culturable bacteria were isolated from buried tyre shreds and identified using fatty acid methyl ester analysis. Isolates belonged to taxonomic groups such as Bacilli, Actinobacteria, Clostridia, Flavobacteria, β and γ‐proteobacteria. For tyre material colonization experiments, Bacillus megatarium, Bacillus cereus, Hydrogenophaga flava, Janthinobacterium lividum, Cellulosimicrobium cellulans, Arthrobacter globiformis (isolated from tyre shreds or leachate at the study site); Escherichia coli and Acidithiobacillus ferrooxidans were used. Beakers containing tyre shreds and artificial rain water were inoculated with a given bacterial culture, incubated at room temperature and sampled at regular intervals. 4′,6‐diamidino‐2‐phenylindole (DAPI) staining followed by epifluorescent microscopy was used to enumerate bacteria in samples. Of the bacteria tested, B. megatarium, J. lividum, E. coli, C. cellulans and A. globiformis exhibited the most extensive colonization of the tyre shreds. However, the extent of colonization varied among bacteria. Response to tyre leachate was also examined using B. cereus and J. lividum. Both bacteria increased in abundance due to the addition of leachate. Conclusions: Bacteria associated with buried tyre shreds were identified and found to include typical soil and freshwater organisms. The majority of indigenous isolates grew on tyre material (or leachate) suggesting that they play an active role in the ecology of these sites and that their potential role in tyre degradation should be explored. Significance and Impact of the study: This study provides information on bacterial communities of tyre‐waste disposal sites, explores the interaction between tyre material and bacteria and identifies bacteria that could be involved in or employed for recycling tyre‐waste.

Next-generation sequencing showing potential leachate influence on bacterial communities around a landfill in China

“…Actinobacteria was found in the D r a f t soil and groundwater samples from both sites but not in the leachate samples. This was not expected as Actinobacteria has previously been found in leachate samples (Vukanti et al, 2009).…”

“…Proteobacteria were most dominantly found in leachate samples from landfills (Song et al, 2015a, Song et al, 2015b and aquifer sediments (Wan et al, 2012). It has been reported that members of Proteobacteria involved in the degradation of aromatic oils such as polycyclic aromatic hydrocarbons (Vukanti et al, 2009). These bacteria have been found to lose dominance in older leachate samples (Köchling et al, 2015) and they were detected at highly abundant levels in aged refuse from Shanghai landfills (Xie et al, 2012).…”

“…To study complex microbial ecosystems such as leachate, molecular techniques have several advantages over culture-based techniques as they allow the analysis of uncultured organisms and provide higher resolution measurements closer to the complete microbial profile (Staley et al, 2011). Analysing the microbial community around a landfill can potentially determine whether the leachate is being transported through the landfill liner into the natural soil and groundwater, via changes in the diversity and composition of bacterial consortia as different species are more or less tolerant of elevated pollutant concentrations (Wang et al, 2017, El-Salam and Abu-Zuid, 2015, Vukanti et al, 2009.…”

Waste tire rubber in polymer blends: A review on the evolution, properties and future

“…Table 11. Tire rubber reclaiming/devulcanization processes [41,46,47] . SEM photomicrographs of A) tensile fractured surface of NR-PBR/RTR blends with different RTR loading [72]; B) tensile fractured surface of NR/GTR and NR/RTR (30phr) [79] C) tensile fractured surface of SBR/GTR and SBR/RTR (30phr) [80]; D) Abrasion pattern on SBR and 30phr GTR filled SBR [69].…”

Improving the properties of reclaimed waste tire rubber by blending with poly(ethylene‐co‐vinyl acetate) and electron beam irradiation

“…RTR is also favored when blending with rubber as the miscibility of the RTR/rubber blends are reported to be better compared GTR/rubber blends (Li et al, 2005, Balasubramanian, 2009, Rooj et al, 2011. Table 2.4 Physical, chemical and microbial processes of tire rubber reclaiming/devulcanization (Myhre et al, 2012, Vukanti et al, 2009, Shah et al, 2013, Shi et al, 2014 …”