INFLUENCE OF PHENOLICS ON BIOMASS PRODUCTION BY CANDIDA-UTILIS AND CANDIDA-ALBICANS

The effect of some lignin degradation products, which can be present in wood hydrolysates, on biomass production by Candida sp. was studied. Suspected inhibitors were used as supplements in growth media for C. utilis and C. albicans containing pure glucose as a carbon energy source. The metabolism of inhibitors by C. utilis and C. albicans is approximately the same and is extremely sensitive to the structure and concentration of the phenolic additive. ID50 and ID100 values for a 50% or a 100% growth inhibition for 20 lignin monomer model compounds during Candida sp. cultivation were established. Comparison of ID values has shown that the least toxic compounds for C. utilis and C. albicans biomass growth and yield are vanillyl alcohol, conipheryl alcohol and syringic acid. The most toxic compounds are salicylic acid, cinnamic acid, benzoic acid and o-vanillin. © 1990.