BIODEGRADATION OF DISPOSABLE POLYETHYLENE BY FUNGI AND STREPTOMYCES SPECIES

The ability of fungi and Streptomyces species to attack degradable pla stics was investigated in pure shake-flask culture studies. The degrad able plastic used in this study was disposable polyethylene bags conta ining 6% starch. Eight different isolated Streptomyces strains and two fungi Mucor rouxii NRRL 1835 and Aspergillus flavus were used. Ten-da y heat-treated (70 degrees C) polyethylene films were chemically disin fected and incubated shaken at 125 rpm at 30 degrees C in 0.6% yeast e xtract medium (pH 7.5) for Streptomyces spp. and for the fungi in 3% y east extract medium (pH 5.5) for 1, 2 and 4 weeks along with an uninoc ulated control for each treatment. Active enzymes caused changes in th e films' mechanical properties and weight. (C) 1998 Elsevier Science L imited. All rights reserved.