Vinasses valorization into short-chain fatty acids: microbiome robustness against process variations

Area of Science:

• Biotechnology and Environmental Science
• Microbial Ecology
• Waste Valorization

Background:

• Vinasse valorization into short-chain fatty acids (SCFAs) via anaerobic fermentation (AF) is an emerging field.
• Controlling operational parameters in AF is crucial due to complex microbial interactions to prevent process destabilization.

Purpose of the Study:

• To evaluate the robustness of the anaerobic fermentation (AF) process for vinasse valorization against deliberate operational perturbations.
• To assess the impact of hydraulic retention time (HRT) and temperature increases on AF stability and microbiome development.

Main Methods:

• Investigated the anaerobic fermentation (AF) of vinasse under perturbed conditions (HRT and temperature increases).
• Quantified SCFA yields and analyzed microbial community structure using microbial analysis.
• Assessed process robustness by comparing microbiome dissimilarity and bioconversion yields under different perturbations.

Main Results:

• Similar SCFA yields (0.5-0.6 g COD-SCFAs/g VS_in) were achieved regardless of the perturbation applied.
• Temperature increase caused a 49.70% microbiome dissimilarity, while HRT increase caused 21.91% dissimilarity.
• Key bacteria identified in vinasse degradation include Clostridiales, Prevotella, and Megasphaera.

Conclusions:

• Anaerobic fermentation (AF) demonstrates robustness against common industrial perturbations, evidenced by stable SCFA yields despite microbiome shifts.
• Functional redundancy within the microbial community contributes to the stability of AF for vinasse valorization.
• AF is a feasible biotechnology for converting vinasse into valuable SCFAs, highlighting its industrial potential.