Metabolic responses of microbial consortia to winery wastewater-associated inhibitors

This study evaluates how non-conventional anaerobic microbial consortia from sanitary landfill leachate and mining wastewater respond to selected winery wastewater-associated inhibitors, including alcohols, carboxylic acids, and phenolic compounds. Batch assays were conducted in nutrient broth acetate-fumarate medium under single and combined inhibitory conditions. The enriched consortia were characterized by full-length 16S rRNA gene sequencing. Both consortia exhibited comparable growth rates under control conditions, but showed distinct growth dynamics, fumarate consumption, succinate and acetate profiles, and inhibitor consumption patterns. The landfill-derived consortium was dominated by Escherichia and displayed faster fumarate consumption under control and alcohol-supplemented conditions, indicating higher baseline substrate turnover. In contrast, the mining-derived consortium showed a more distributed taxonomic profile, dominated by Proteus, Wolinella, and Escherichia, and maintained fumarate consumption more consistently under carboxylic acid and phenolic stress. Alcohols had limited effects on growth and fumarate consumption, whereas carboxylic acids significantly reduced growth and altered metabolite profiles. Phenolic compounds exerted a strong inhibitory effect, particularly at high concentrations. Catechol and tyrosol showed only minor concentration changes, consistent with low apparent consumption under the tested anaerobic conditions. Under combined inhibitory conditions, both consortia maintained fumarate consumption and metabolite formation despite reduced growth, with the mining-derived consortium showing increased fumarate consumption and enhanced succinate production. Microbial source, enrichment history, community composition, and inhibitory conditions jointly shaped the resilience and metabolic performance of the anaerobic consortia. This work supports screening non-conventional microbial consortia for future anaerobic and bioelectrochemical treatment of chemically complex agro-industrial wastewater. KEY POINTS: • Non-conventional anaerobic consortia maintained activity under inhibition • Taxonomic composition was associated with distinct metabolic profiles • Phenolics caused strong inhibition and low apparent anaerobic consumption.