Characterization and Anaerobic Fermentation of Extracellular Polysaccharide

ECP was used and prepared as previously described [1 (link),2 (link),3 (link)]. ECP was mainly composed of rhamnose (49.7%), glucose (29.9%), glucuronic acid (10.8%), and xylose (7.2%). In addition, small amounts of mannose (1.0%) and galactose (1.3%) were also detected. The molecular weight of ECP was 11.67 kDa, and the sulfate content of ECP was 14.7%. Bacterial nutrients used for the in vitro anaerobic fermentation were all obtained from Sigma-Aldrich (St. Louis, MO, USA). The standard SCFA solutions, including lactate, acetate, propionate, and butyrate, were also obtained from Sigma-Aldrich (St. Louis, MO, USA). Hemin and L-cysteine hydrochloride used for the fermentation were purchased from Sangon Biotech (Shanghai, China). All other analytical-grade chemicals were acquired from Sinopharm Chemical (Shanghai, China).