INFLUENCE OF CELL IMMOBILIZATION ON THE PRODUCTION OF BENZALDEHYDE AND BENZYL ALCOHOL BY THE WHITE-ROT FUNGI BJERKANDERA-ADUSTA, ISCHNODERMA-BENZOINUM AND DICHOMITUS-SQUALENS

Three white-rot basidiomycetes, Bjerkandera adusta, Ischnoderma benzoi num and Dichomitis squalens, were cultivated on a liquid medium supple mented with L-phenylalanine, a precursor for benzaldehyde (bitter almo nd aroma) and benzyl alcohol. Remarkable amounts of benzaldehyde (587 mg 1(-1)) were found in cultures of B. adusta. Immobilization of this fungus on polyurethane foam cubes allowed an 8.3-fold increase of the production of benzaldehyde and a 15-fold increase of the productivity as compared with non-immobilized cells. Aryl-alcohol oxidase activity was only detected in B. adusta. This activity was also significantly e nhanced in immobilized cells, suggesting that it plays an important ro le in benzaldehyde biosynthesis. Conversely, consistent amounts of ben zyl alcohol (340 mg 1(-1) for B. adusta and I. benzoinum and 100 mg 1( -1) for D. squalens) were produced by the three fungi when immobilized . Laccase activity was found only in the strains I. benzoinum and D. s qualens. This activity was markedly enhanced in free cells cultures. I mmobilization of the fungi did not promote benzyl alcohol production b y comparison with ft ee cell cultures (500 mg 1(-1)).