Effects of the Organic Loading Rate on Polyhydroxyalkanoate Production from Sugarcane Stillage by Mixed Microbial Cultures

Author(s)

Duarte de Oliveira, Guilherme Henrique ^[1] ; Krauspenhar Niz, Mirian Yasmine ^[2] ; Zaiat, Marcelo ^[2] ; Domingues Rodrigues, Jose Alberto ^[1]

Affiliation

^[1] Maua Inst Technol EEM IMT, Maua Sch Engn, 1 Praca Maua, BR-09580900 Sao Caetano do Sul, SP - Brazil

^[2] Univ Sao Paulo, Sao Carlos Sch Engn, Ctr Res Dev & Innovat Environm Engn, Lab Biol Proc, 1100, Joao Dagnone Ave, BR-13563120 Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: Applied Biochemistry and Biotechnology; v. 189, n. 4, p. 1039-1055, DEC 2019.
• Web of Science Citations: 0

Abstract

Stillage is an abundant wastewater from the sugarcane ethanol industry. It is rich in fermentable substrates and presents low-nutrient content, constituting a promising substrate for polyhydroxyalkanoate (PHA) production by mixed microbial cultures (MMC). This work assessed the enrichment of a PHA-accumulating MMC from acidified sugarcane stillage in a sequencing batch reactor under increasing organic loading rates (OLR) and no external nutrient supplementation. The OLR was increased from 1.0 to 7.1 kg COD m(-3) day(-1) in four steps. A PHA-producing MMC with high storage response was selected in all experimental conditions. The volumetric biomass productivity and the maximal PHA storage capacity increased continuously with the OLR, reaching 0.061 g VSS L-1 h(-1) and 0.49 g PHA g VSS-1, respectively. The highest observed PHA storage yield (0.60 g CODPHA g COD.t(-1)) and specific PHA storage rate (0.169 g CODPHA g of CODX h(-1)) were obtained for the OLR of 4.5 kg COD m(-3) day(-1). The PHA produced was a co-polymer of 3-hydroxybutyrate (86-77%mol) and 3-hydroxyvalerate (14-23%mol). The performance of the biomass enrichment was comparable to those attained with other agro-industrial wastewaters, indicating the potential of acidified sugarcane stillage as a feedstock for MMC PHA production. (AU)

• FAPESP's process: 16/01253-8 - Polyhydroxyalkanoates production from sugarcane vinasse by mixed cultures
• Grantee: Guilherme Henrique Duarte de Oliveira
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• 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