THE PRODUCTION OF CELLULASE BY FUNGI ON MIXED CELLULOSIC SUBSTRATES

Abstract

Using jute, alkali-treated jute, holocellulose from jute, and filter paper as substrates, a total of 124 fungi were tested for production of cellulolytic enzyme capable of hydrolyzing powdered filter paper and swollen cellulose. Of these, only 15 organisms failed to produce the enzyme on any substrate, and 48 produced cellulase on filter paper, so that in most species cellulase production could be induced only by mixed cellulosic substrates. Among such species were many that are ordinarily regarded as non-cellulolytic, while on the other hand comparatively little enzyme could be detected with several well-known cellulose decomposers strongly degrading cellulose in vivo. Factors stimulating enzyme production on mixed cellulosic substrates were micronutrients and hemicellulose. For most species, excluding a few of the strong cellulose decomposers, a partial loosening of the hemicellulose seemed to favor enzyme production best. Some cellulase was produced on free hemicellulose alone, but not on starch and sugars, although in presence of cellulose these substances stimulated enzyme production by a few ordinarily weak species; on strong cellulose decomposers the effect of these additional carbon sources was opposite, possibly due to a sparing action on cellulose.