Anaerobic digestion of saline waste activated sludge and recovering raw sulfated polysaccharides

This study investigated a new bioresource technology of recovering raw chemicals of sulfated polysaccharides (SPs) from the digested saline waste activated sludge (WAS_saline) that naturally contained 3-30% (w/w) of SPs. Two bench-scale anaerobic digestion (AD) experiments were conducted under mesophilic and thermophilic conditions; the effectiveness of extracting SPs from digested WAS_saline and the biochemical characteristics of SPs were examined. After 20-days of digestion, the results showed that approximately 54 - 58% of initial total SPs in WAS_saline were recoverable, in which 38 - 48% in solid digestate and 10-15% in liquid supernatant). The extracted raw chemicals of SPs were proven to be of high purity (>80%) and demonstrating significant properties such as anti-inflammation, anti-oxidation, and anti-coagulation for potential pharmaceutical-like application.