Bioaugmentation with Enterococcus casseliflavus: A Hydrogen-Producing Strain Isolated from Citrus Peel Waste

Author(s)

Camargo, Franciele Pereira ^[1] ; Sakamoto, Isabel Kimiko ^[1] ; Silva, Edson Luiz ^[2] ; Duarte, Iolanda Cristina Silveira ^[3] ; Varesche, Maria Bernadete Amancio ^[1]

Affiliation

^[1] Univ Sao Paulo, Sch Engn Sao Carlos, Dept Hydraul & Sanitat, Ave Trabalhador Sao Carlense 400, BR-13566590 Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Carlos, Dept Chem Engn, Rod Washington Luiz, Km 235, SP 310, BR-13565905 Sao Carlos, SP - Brazil

^[3] Fed Univ Sao Carlos UFSCar, Dept Biol, Joao Leme dos Santos Highway, Km 101, BR-18052780 Sorocaba, SP - Brazil

• Document type: Journal article
• Source: WASTE AND BIOMASS VALORIZATION; v. 12, n. 2, SI, p. 895-911, FEB 2021.
• Web of Science Citations: 1

Abstract

Purpose To isolate, identify and characterize an anaerobic strain from in natura CPW, in relation to the consumption of different carbon sources, growth kinetics and H-2 production after bioaugmentation. Methods Several substrates were evaluated (glucose, fructose, sucrose, xylose, starch, cellobiose, cellulose and lactose), and its optimal concentration was evaluated by Experimental Design method, besides the application of the isolated strain in citrus peel waste (CPW). Results A facultative anaerobic strain, similar (99%) to Enterococcus casseliflavus, was isolated from in natura citrus pulp and bagasse. Xylose was the monomer from which there was greater H-2 production (10.3 mmol L-1). For 0.5 to 6.5 g(xylose) L-1, 3.0 to 12.9 mmol H-2 L-1 was obtained, respectively. Generation time (Tg) of 0.35 h and specific growth (mu) of 1.98 h(-1) for pH 7.0, 37 degrees C and 2 g (glucose) L-1 was obtained for E. casseliflavus. In bioaugmentation assays (CPW + E. casseliflavus), highest maximum H-2 production potential (P = 13.9 mmol L-1), maximum H-2 production rate (Rm = 1.09 mmol h(-1)) and time to start the H-2 production (lambda = 2.12 h(-1)) was observed when compared to glucose (P = 9.1 mmol L-1; Rm = 1.99 mmol h(-1); lambda = 4.08 h(-1)). Conclusion From glucose, there was prevalence of butyric acid pathway (759 mg L-1) in relation to acetic acid (303 mg L-1). From CPW, there was higher production of acetic acid (878 mg L-1) in relation to butyric (147 mg L-1). The application of E. casseliflavus by bioaugmentation is an alternative for biodigestion of complex substrates, such as CPW, to obtain products of biotechnological interest. {[}GRAPHICS] . (AU)

• 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: 17/01722-0 - Biogas obtainment and other compounds of biotechnological interest from citrus/orange processing residues
• Grantee: Franciele Pereira Camargo
• Support Opportunities: Scholarships in Brazil - Doctorate