Iron and nickel nanoparticles role in volatile fatty acids production enhancement: Functional genes and bacterial taxonomy in an anaerobic fluidized bed reactor

Author(s)

Moura, A. G. L. ; Delforno, T. P. ; Rabelo, C. A. B. S. ; Kumar, G. ; Silva, E. L. ; Varesche, M. B. A.

• Document type: Journal article
• Source: Biochemical Engineering Journal; v. 187, p. 12-pg., 2022-10-07.

Abstract

This study is the first report that describes Iron (16.7 mg Fe0 g-1) and Nickel (0.04 mg Ni0 g-1) nanoparticles (NPs) immobilization on the support material of an Anaerobic Fluidized Bed Reactor (AFBR-NP) and the assessment of its influence on fermentation pathway when compared with a reactor without NPs (AFBR-Control). AFBRs were operated at initial pH 6.8, 37 degrees C, 3.0 h Hydraulic Retention Time. Natural fermentation along with bio-augmentation with Clostridium butyricum were used as inoculation strategy. Both reactors were fed with glucose as main substrate (56 +/- 6 and 21 +/- 2 g COD L-1 d-1 at operational Stages I and II, respectively). 78-98% higher Volatile Fatty Acid (VFA) was observed on AFBR-NP. Metals higher availability specifically favored butyric (1.04 +/- 0.37 g L-1) and acetic (1.22 +/- 0.33 g L-1) acid production metabolic route on AFBR-NP. Under the same operational conditions, lactic acid was observed as main metabolite on AFBR-Control (1.23 +/- 0.25 g L-1). En-zymes related to butyric (butyryl-CoA dehydrogenase, phosphate butyryltransferase, butyrate kinase) and pro-pionic acid (pyruvate-ferredoxin oxidoreductase) metabolic routes were identified on AFBR-NP reactor biofilm. Through these results, it is possible to infer that Fe0 and Ni0 NPs could effectively improve VFA production and the fermentation process. (AU)

• FAPESP's process: 17/23008-8 - Assessment of Iron and Nickel nanoparticles influence on batch and continuous reactors fermentative hydrogen production
• Grantee: Alana Gandra Lima de Moura
• 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
• FAPESP's process: 18/26470-7 - Influence of sugarcane bagasse saccharification by laccase for fermentative production of biofuels
• Grantee: Camila Abreu Borges da Silva Rabelo
• Support Opportunities: Scholarships in Brazil - Post-Doctoral