Dominant species identification of a microbial consortium efficient in diesel degradation

This study shows the dominant microbial species of a microbial consortium efficient in the hydrocarbon degradation, which was obtained from a sinkhole (cenote) in the Mexican Caribbean in Playa del Carmen. The microbial consortium was characterized and identified. The indices of the number of species were also analyzed. Five genera of bacteria corresponding to the consortium were identified, and it was possible to discard those that were only tolerant to hydrocarbons from those that degraded them. The 38 % of bacteria corresponded to Enterobacteriales ( Escherichia coli, Klebsiella pneumoniae, Salmonella typhimurium, Shigella flexneri, and Proteus mirabilis); E. coli is the only not being reported as hydrocarbonoclast but tolerant to hydrocarbons. The 23 % corresponded to Vibrionales ( Vibrio cholerae pacini, Vibrio parahemolyticus, and Vibrio vulnificus). The 15 % corresponded to Lactobacillales ( Enterococcus faecalis, Enterococcus faecium, and Streptococcus bovis). Lastly, Pseudomonas aeruginosa and Burkholderia cepacia represented 8 % of the total. The observed total microbial species richness (OTU) was 6 in the MacConkey agar and Endo agar media, as well as a Chao1 index of 21, both corresponding to enterobacteria. The identification of the bacteria and dominant species in the consortium carried out in this study contributes to the knowledge for establishing growth conditions to achieve a more significant degradation of polycyclic aromatic hydrocarbons.