title: Consolidated bioprocessing of microalgal biomass to carboxylates by a mixed culture of cow rumen bacteria using anaerobic sequencing batch reactor (ASBR).
abstract: This study employed mixed-culture consolidated bioprocessing (CBP) to digest microalgal biomass in an anaerobic sequencing batch reactor (ASBR). The primary objectives are to evaluate the impact of hydraulic residence time (HRT) on the productivity of carboxylic acids and to characterize the bacterial community. HRT affects the production rate and patterns of carboxylic acids. For the 5-L laboratory-scale fermentation, a 12-day HRT was selected because it offered the highest productivity of carboxylic acids and it synthesized longer chains. The variability of the bacterial community increased with longer HRT (R2=0.85). In the 5-L laboratory-scale fermentor, the most common phyla were Firmicutes (58.3%), Bacteroidetes (27.4%), and Proteobacteria (11.9%). The dominant bacterial classes were Clostridia (29.8%), Bacteroidia (27.4%), Tissierella (26.2%), and Betaproteobacteria (8.9%).
authors.affiliation: Graduate School, Chinese Academy of Agricultural Sciences, Beijing 100081, China; Biological Systems Engineering, Washington State University, Pullman, WA 99164, USA.
authors.forename: Baisuo
authors.initials: B
authors.lastname: Zhao
authors.affiliation: Rural Energy Institute, Heilongjiang Academy of Agricultural Sciences, Harbin 150086, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.affiliation: Biological Systems Engineering, Washington State University, Pullman, WA 99164, USA.
authors.forename: Craig
authors.initials: C
authors.lastname: Frear
authors.affiliation: Department of Chemical Engineering, Texas A&M University, College Station, TX 77843, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Holtzapple
authors.affiliation: Biological Systems Engineering, Washington State University, Pullman, WA 99164, USA. Electronic address: chens@wsu.edu.
authors.forename: Shulin
authors.initials: S
authors.lastname: Chen
mesh_terms: D000818:Animals; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D018533:Biomass; D019149:Bioreactors / Q000382:microbiology*; D001709:Biotechnology / Q000295:instrumentation / Q000379:methods*; D002264:Carboxylic Acids / Q000378:metabolism; D002417:Cattle; D005260:Female; D005285:Fermentation; D058086:Microalgae / Q000378:metabolism*; D059013:Microbial Consortia / Q000235:genetics / Q000502:physiology; D012417:Rumen / Q000382:microbiology*
chemical_list: D002264:Carboxylic Acids
keywords: ASBR reactor; Algal biomass; Carboxylates; Consolidated bioprocessing; Cow rumen bacteria