Poly(sodium carboxylate)s containing vinyl alcohol blocks were prepared, and their microbial degradability and the poly(vinyl alcohol) (PVA) dehydrogenase activity as a function of vinyl alcohol block length in the polymer chain were analyzed. A clear relationship between the biochemical oxygen demand (BOD) biodegradability using the activated sludge and the relative activity of PVA dehydrogenase of a PVA-assimilating strain, Alcaligenes faecalis KK314, was observed. A vinyl alcohol block length of about 7 monomer units corresponds to the minimum chain length of the vinyl alcohol block length which acts as a biodegradable segment in the poly[(disodium fumarate)-co-(vinyl alcohol)]. The enzymatic cleavability of polycarboxylates containing vinyl alcohol blocks was estimated using the cell-free extracts of a PVA-assimilating microbial strain, A. faecalis KK314, as the PVA-cleaving enzyme source for both PVA dehydrogenase and hydrolase. The molecular weight of the polycarboxylates was reduced depending on the vinyl alcohol block length, and a similar molecular weight reduction tendency was observed with respect to the BOD values and PVA dehydrogenase activities.
ASJC Scopus subject areas