New Insights into Controlling Homoacetogenesis in the Co-digestion of Coffee Waste: Effect of Operational Conditions and Characterization of Microbial Communities

Author(s)

Villa Montoya, Alejandra Carolina ^[1] ; da Silva Mazareli, Raissa Cristina ^[1] ; Delforno, Tiago Palladino ^[2] ; Centurion, Victor Borin ^[3] ; de Oliveira, Valeria Maia ^[3] ; Silva, Edson Luiz ^[4] ; Amancio Varesche, Maria Bernadete ^[1]

Affiliation

^[1] Univ Sao Paulo, Sao Carlos Sch Engn, Dept Hydraul & Sanitat, Lab Biol Proc, Campus 2, BR-13563120 Sao Carlos, SP - Brazil

^[2] SENAI Innovat Inst Biotechnol, BR-01130000 Bom Retiro, SP - Brazil

^[3] Univ Estadual Campinas, Res Ctr Chem Biol & Agr CPQBA, Microbial Resources Div, BR-13081970 Campinas, SP - Brazil

^[4] Univ Fed Sao Carlos, Ctr Exact Sci & Technol, Dept Chem Engn, BR-13565905 Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: Applied Biochemistry and Biotechnology; NOV 2021.
• Web of Science Citations: 0

Abstract

In this research batch reactors were operated with coffee processing waste and autochthonous microbial consortium, and a taxonomic and functional analysis was performed for phase I of stabilization of maximum H-2 production and for phase II of maximum H-2 consumption. During phase I, the reactor's operating conditions were pH 4.84 to 8.18, headspace 33.18% to 66.82%, and pulp and husk from 6.95 to 17.05 g/L. These assays continued for phase II, with initial pH conditions of 5.8-8.1, headspace of 33.18-66.82%, and pulp and husk remaining from phase I. The highest homoacetogenesis was observed in assay 5 with pH 7.7, 40% headspace, and 15 g/L of pulp and husk (initial concentrations of phase I). A relative abundance of Clostridium 41%, Lactobacillus 20% and Acetobacter 14% was observed in phase I. In phase II, there was a change in relative abundance of 21%, 63%, and 1%, respectively, and functional genes involved with autotrophic (formyltetrahydrofolate synthase) and heterotrophic (enolase) homoacetogenesis, butanol (3-hydroxybutyryl-CoA dehydrogenase), and propionic acid (propionate CoA-transferase) were identified. This study provides a new and amplified insight into the physicochemical and microbiological factors, which can be used to propose adequate operational conditions to maximize the bioenergy production and reduce homoacetogenesis in biological reactors. (AU)

• FAPESP's process: 16/20047-0 - Assessment of physicochemical and phylogenetic features in the hydrogen production and Homoacetogenesis from wastes of coffee processing
• Grantee: Alejandra Carolina Villa Montoya
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 15/06246-7 - Biorefinery concept applied to biological wastewater treatment plants: environmental pollution control coupled with material and energy recovery
• Grantee: Marcelo Zaiat
• Support Opportunities: Research Projects - Thematic Grants