Consecutive lactate formation and chain elongation to reduce exogenous chemicals input in repeated-batch food waste fermentation.

摘要: Abstract The production of biochemicals from renewables through biorefinery processes is important to reduce the anthropogenic impact on environment. Chain elongation based microbiomes have been successfully developed produce medium-chain fatty acids (MCFA) organic waste streams. Yet, sustainability chain can still be improved by reducing use electron donors and additional chemicals. This work aimed couple lactate subsequent decrease chemicals input such as hydroxide for pH control in repeated-batch food fermentation. Food with adjusted was used substrate fermentation proceeded without control. During fermentation, first formed homolactic pathway then converted (FA), mainly n-butyrate n-caproate. highest n-caproate carbon selectivities (mmol C/mmol CFA) rates were 38% 4.2 g COD/L-d, respectively. Hydroxide reduced over time a minimum 0.47 mol OH−/mol MCFA or 0.79 mol OH−/kg CODFA. Lactate key donor its conversion observed at low 4.3. microbiome enriched this dominated Lactobacillus spp. Caproiciproducens high abundance their co-occurrence suggest elongation. shows decreased no exogenous donors.