title: Biodegradation of nanocrystalline cellulose by two environmentally-relevant consortia.
abstract: Nanocellulose is growing in popularity due to its versatile properties and applications. However, there is a void of knowledge regarding the environmental fate of nanocellulose and the response of environmental microbial communities that are historically adapted to non-nano cellulose forms. Given its distinction in terms of size and chemical and physical properties, nanocellulose could potentially resist biodegradation and/or pose a xenobiotic influence on microbial communities during wastewater treatment or in receiving environments. In this study, biodegradation of H2SO4hydrolyzed nanocrystalline cellulose (HNC) was compared with that of microcrystalline cellulose using two distinct anaerobic cellulose-degrading microbial consortia initially sourced from anaerobic digester (AD) and wetland (W) inocula. Equivalent cellulose masses were dosed and monitored with time by measurement of liberated glucose. HNC biodegraded at slightly faster rate than microcrystalline cellulose (1st order decay constants: 0.62 ± 0.08 wk-1for HNC versus 0.39 ± 0.05 wk-1for microcrystalline cellulose for the AD consortium; 0.69 ± 0.04 wk-1for HNCversus 0.58 ± 0.05 wk-1for microcrystalline cellulose for the W consortium). 16S rRNA (total bacteria) and cel48 (glycoside hydrolase gene family 48, indicative of cellulose-degrading potential) genes were observed to be more enriched in the HNC condition for both consortia. According to Illumina amplicon sequencing of 16S rRNA genes, the composition of the consortia underwent distinct shifts in concert with HNC versus microcrystalline cellulose degradation. This study demonstrates that the biodegradation of cellulose is not inhibited in the nano-size range, particularly in the crystalline form, though the microbes and pathways involved likely differ.
authors: Department of Civil Engineering, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India.
authors: Gargi
authors: G
authors: Singh
authors: Spectrix Analytical Services, Lawrenceville, NJ 08648, USA.
authors: Cody
authors: C
authors: Chandoha-Lee
authors: Department of Sustainable Biomaterials, Virginia Tech, Blacksburg, VA 24060, USA; Macromolecules and Interfaces Institute, Virginia Tech, Blacksburg, VA 24060, USA.
authors: Wei
authors: W
authors: Zhang
authors: Department of Wood Science, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
authors: Scott
authors: S
authors: Renneckar
authors: Charles E. Via, Jr. Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA 24060, USA.
authors: Peter J
authors: PJ
authors: Vikesland
authors: Charles E. Via, Jr. Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA 24060, USA. Electronic address: apruden@vt.edu.
authors: Amy
authors: A
authors: Pruden
mesh_terms: D001419:Bacteria / Q000378:metabolism; D001673:Biodegradation, Environmental; D002482:Cellulose / Q000378:metabolism*; D059013:Microbial Consortia; D012336:RNA, Ribosomal, 16S / Q000235:genetics*
chemical_list: D012336:RNA, Ribosomal, 16S; D002482:Cellulose
keywords: Anaerobic digester; Biodegradation; Microbial community shift; Nanocellulose; Next generation DNA sequencing; Wetland