A kinetic analysis of the fungal degradation process of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) in soil

Fungal degradation of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) film in soil was described mathematically in terms of the surface growth rate of fungal hyphae and the degradation ability of fungal depolymerase. The surface growth rate of fungi was derived from the notion of equivalent symmetric tree model and was expressed for the two different growth phases, i.e. exponential phase and deceleration phase. The proposed growth and degradation models represented well the experimental data obtained from fungal PHBV degradation in soil. Fungi degrade PHBV film with the formation of soil aggregate that gives the advantageous condition for fungal growth and PHBV degradation. Fungal degradation rate of PHBV film in soil depends on the population of colonized fungal biomass on PHBV film surface and their degradation ability. (C) 2001 Elsevier Science B.V. All rights reserved.