Biodegradation of superabsorbent polymers in soil

Biodegradation of two superabsorbent polymers, a crosslinked, insoluble pol yacrylate and an insoluble polyacrylate/polyacrylamide copolymer, in soil b y the white-rot fungus, Phanerochaete chrysosporium was investigated. The p olymers were both solubilized and mineralized by the fungus but solubilizat ion and mineralization of the copolymer was much more rapid than of the pol yacrylate. Soil microbes poorly solublized the polymers and were unable tu mineralize either intact polymer. However, soil microbes cooperated with th e fungus during polymer degradation in soil, with the fungus solubilizing t he polymers and the soil microbes stimulating mineralization. Further, soil microbes were able tu significantly mineralize both polymers after solubil ization by P. chrysosporium grown under conditions that produced fungal per oxidases or cellobiose dehydrogenase, or after solubilization by photochemi cally generated Fenton reagent. The results suggest that biodegradation of these polymers in soil is best under conditions that maximize solubilizatio n.