Study of supercritical carbon dioxide pretreatment processes on green coconut fiber to enhance enzymatic hydrolysis of cellulose

Author(s)

Putrino, Fernando Marques ^[1] ; Tedesco, Marcela ^[1] ; Bodini, Renata Barbosa ^[1] ; de Oliveira, Alessandra Lopes ^[1]

Affiliation

^[1] Univ Sao Paulo, Fac Anim Sci & Food Engn FZEA, Dept Food Engn, Av Duque de Caxias Norte 225, BR-13635900 Pirassununga, SP - Brazil

• Document type: Journal article
• Source: Bioresource Technology; v. 309, AUG 2020.
• Web of Science Citations: 0

Abstract

Green coconut fiber was treated by supercritical CO2 with the aim to enhance hydrolysis of its enzymatic cellulose. To this end, different static conditions of CO2 contact times (3 and 5 h) and polarity modifiers (NaOH, NaHSO4, ethanol) were evaluated at 20 MPa, 70 degrees C and 1 h of dynamic extraction followed by fast depressurization. After supercritical CO2 exposition, SEM images showed fiber damage and FTIR spectra showed decreases of phenolic and wax contents, including a reduction in the degree of the hydrogen bond established between lignin and cellulose. Despite the apparent delignification, supercritical CO2 did not enhance cellulose enzymatic hydrolyses. Fiber exposed to supercritical CO2 (5 h) demonstrated that the highest sugar content (540.9 mu mol glucose likely limited supercritical CO2 delignification; however, green coconut in natura can be an innovative substrate for fermentation in alcohol production. (AU)

• FAPESP's process: 10/16665-3 - Green coffee oil extraction by supercritical and pressurized fluid process, and comparison with the composition of coffee oil obtained by pressing for the small producers of the State of São Paulo - concentration analysis of bioactive diterpenes
• Grantee: Alessandra Lopes de Oliveira
• Support Opportunities: Regular Research Grants