Microbial community dynamics reflect reactor stability during the anaerobic digestion of a very high strength and sulfate‐rich vinasse

Abstract

BACKGROUND Microbial community dynamics during the anaerobic digestion of vinasse has been little studied. However, having knowledge about it is essential for early detection of reactor operational difficulties to apply preventive actions. This research studies the microbial community dynamics in the anaerobic digestion of vinasse, linking to experimental observations about product yields and organic matter degradation. RESULTS Methane and sulfide yields decreased with increasing SO42‐/COD ratio, while the fraction of organic matter degraded by sulfate reducing bacteria increased from 4.5 ± 0.3% to 27.1 ± 0.6%. The archaeal community showed that acetoclastic Methanosaetaceae were little affected by the increase of the SO42‐/COD ratio, in contrast to the Methanomicrobiales and Methanobacteriales population, which decreased during the experiment. The total bacterial diversity was influenced mainly by substrate composition, showing that the increase of the SO42‐/COD ratio above 0.10 shifted the bacterial community to a lower richness. CONCLUSION These results provide knowledge on the dynamics of the microbial communities, which can be useful to control the anaerobic digestion of sulfate‐rich vinasses, showing that reactor stability equates to the higher ratios between total methanogens and total bacteria gene copy numbers, whereas operational difficulties can be associated to lower bacterial richness and higher community organization. © 2017 Society of Chemical Industry

Temperature Effects on Methanogenesis and Sulfidogenesis during Anaerobic Digestion of Sulfur-Rich Macroalgal Biomass in Sequencing Batch Reactors

“…In RM, Methanotrichaceae was the major methanogenic group (42.9%-91.0%), indicating that aceticlastic methanogenesis was likely the major pathway for methane production ( Figure 6A). Methanotrichaceae is generally considered indicative of a balanced AD with low residual VFAs [38]. The methanogenic community structures of RM and inoculum, in which Methanosarcinaceae was predominant, were significantly different, although both originated from mesophilic systems ( Figure 6A).…”

Molecular identification of microbial communities in the methane production from vinasse: A review

“…The double-stranded fragments are separated in polyacrylamide gel with urea-formamide depending on their nucleotide sequence (Myers et al 1987;Muyzer et al 1993). In PCR-DGGE, P338f-GC and P518r (Jiménez et al 2018), 1055F / 1392R-GC (Dias et al 2016), and 968FGC-1401R (Rodríguez et al 2012;dos Reis et al 2015) primers have been used for the study of bacterial communities in the AD of vinasse. For the Domain Archaea, Parch519fGC / Arch915r and A109 (T) -F / 515-GC-R primers have been used (Rodríguez et al 2012;dos Reis et al 2015).…”

“…For the Domain Archaea, Parch519fGC / Arch915r and A109 (T) -F / 515-GC-R primers have been used (Rodríguez et al 2012;dos Reis et al 2015). Also, denaturing gradients ranging from 45% to 60% (Jiménez et al 2018) and 30% to 70% (Dias et al 2016) have been used. Other studies have used a gradient of 42% to 67% and 30% to 60% for bacterial and archaeal communities.…”

“…Other studies have used a gradient of 42% to 67% and 30% to 60% for bacterial and archaeal communities. The DGGE profiles have been analyzed with the Bionumerics software 5.1 (Applied Maths, Kortrijk, Belgium) (Jiménez et al 2018), BioNumerics 7.1 (Dias et al 2016) and BioNumerics 2.5 (dos Reis et al 2015). The bands obtained are excised, crushed, eluted in milliQ water, re-amplified, purified, and sequenced (Bailón-Salas et al 2017b).…”

“…So, the lack of knowledge of the microbial communities present in AD of vinasse limits the capacity to maximize the methane production. In AD of vinasse, changes in the structure of microbial communities have been rarely studied (Jiménez et al 2018). In the next sections, molecular techniques for the microorganism identification in diverse vinasses are summarized.…”