Location: Bioproducts ResearchTitle: Changes on structural characteristics of cellulose pulp fiber incubated for different times in anaerobic digestate
|TONOLI, GUSTAVO H D - Federal University Of Lavras|
|SILVA, LUIZ EDUARDO - Federal University Of Lavras|
|Wood, Delilah - De|
|OLIVEIRA, JULIANO E - Embrapa|
|FONSECA, ALESSANDRA D S - Federal University Of Lavras|
|Glenn, Gregory - Greg|
|Orts, William - Bill|
Submitted to: Cerne
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/6/2021
Publication Date: 4/5/2021
Citation: Tonoli, G., Holtman, K.M., Silva, L., Wood, D.F., Torres, L.F., Williams, T.G., Oliveira, J., Fonseca, A., Klamczynski, A.P., Glenn, G.M., Orts, W.J. 2021. Changes on structural characteristics of cellulose pulp fiber incubated for different times in anaerobic digestate. Cerne. 27. Article e-102647 . https://doi.org/10.1590/01047760202127012647.
Interpretive Summary: Cellulose is an important biopolymer and plays a major role in achieving the goal of sustainable agriculture. Cellulose processability is commonly achieved by treatment with concentrated acids or alkalis. Such treatments generate large quantities of waste for disposable at a considerable cost and environmental impact. Treatment with microbial-derived enzymes is an attractive alternative as an environmentally sound process. Anaerobic bacteria that excrete enzymes into the surrounding environment serve as a continuously regenerating source of enzymes for cellulose treatment thereby improving processability. Treatment of wood pulp using the bacterial digestate partially removed the amorphous components of the pulp fiber resulting in a material with a high crystalline content. Such treatments show potential as mechanism for use in engineered fiber-based materials where the high crystallinity results in materials with improved strength and durability.
Technical Abstract: The present work has the objective of investigating the pre-treatment of microbial-rich digestate (liquid mesophilic anaerobic digestate – AD-supernatant) influence on the morphology, crystallinity, and thermal stability of cellulose pulp fiber. The six most abundant bacteria in the AD-supernatant were determined by 16S analysis. The bacteria population was comprised mostly of Bacteroides graminisolvens (66%) and Parabacteroides chartae (28%). Enzymatic activity from the bacteria partially removed the amorphous components and increased the crystallinity and crystallite size of the cellulose substrate. The fiber pulp was incubated in AD-supernatant for 5, 10, and 20 days. The X-ray diffraction data provided evidence that the amorphous portion of the cellulose was more readily and quickly hydrolyzed than the crystalline portion. The longest incubation times (20 days) resulted in substantial deconstruction of the cellulose fiber structure and decreased the thermal degradation temperature. The anaerobic digestate is inexpensive and could be used to effectively aid in the pre-treatment of cellulose on large scale transformation processes, e.g. for making biofuels, cellulose micro/nanofiber production or engineered fiber-based materials.