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The proteins of Coriolus versicolor treated with the acetone extracts of Cinnamomum camphora xylem has been investigated. The specific proteins found in the extract treated C. versicolor, were characterized by two-dimensional (2D) gel electrophoresis (2D-GE) and identified by matrix assisted laser desorption ionization (MALDI) combined with tandem time-of-flight microscopy, i.e. TOF-MS/TOF-MS. Most of 474 proteins detected from the pure culture were common metabolic proteins. Nineteen protein spots changed significantly and 17 spots were identified successfully. The 19 proteins were assigned to 10 functional groups including ion binding, translation factor activity, nucleic acid binding and ATPase activity. These proteins are involved in signal transduction, transport and membrane trafficking. The down regulated expression of translation elongation factor 1 alpha (EF1α), α-tubulin, and tropomyosin-1 showed that protein translation elongation, growth-stimulating signal transduction, signal transduction and material transport were suppressed, which resulted in the apoptosis of the pathogen. These findings provide a better understanding of the anti-fungal mechanism of C. camphora and indicate the way for the development of wood preservatives based on natural extracts.

Antifungal activity of constituents from the heartwood of the Malaysian Gmelina arborea against Trametes versicolor and Fomitopsis palustris was investigated. A sensitive bioassay system for antifungal activity against basidiomycetes was developed which uses a medium in which homogenized hyphae were dispersed. Ethyl acetate- solubles from the heartwood showed the highest activity against both fungi, although the activity against F. palustris was quite weak. Spots exhibiting antifungal activity against T. versicolor were specified by autobiography of ethyl acetate-solubles, and five constituents were isolated and identified as (+)-7′-O-ethyl arboreol, (+)-paulownin, (+)-gmelinol, (+)-epieudesmin and (−)-β-sitosterol. The four lignans showed antifungal activity, whereas β-sitosterol did not. From the comparison of antifungal activity, it was concluded that the piperonyl nucleus contributed to the activity of lignans. Of the four lignans isolated, gmelinol appeared to be an important antifungal constituent, since it was rich in the heartwood of G. arborea. Furthermore, the synergism by coexistence of these five compounds was confirmed.

Summary The antifungal activity of cadinane skeletal sesquiterpenoids from Taiwania (Taiwania cryptomerioides Hayata) heartwood is demonstrated. Using spectral analyses, the absolute structures of three main cadinanes, T-cadinol, T-muurolol, and α-cadinol, all isolated from Taiwania with HPLC, were identified. The amount of these cadinanes was also quantified using GC. The results showed that the total amount of cadinanes extracted from heartwood with n-C6H14 was 6.49 mg per kg of wood. This was much more than the essential oils collected by water distillation from leaves (0.04 mg/kg), sapwood (0.36 mg/kg), or heartwood (1.77 mg/kg). Moreover, results obtained from the antifungal assays demonstrated that αcadinol exhibited the highest antifungal index for both Coriolus versicolor and Laetiporus sulphureus, followed by T-cadinol and T-muurolol. As a matter of fact, α-cadinol completely inhibited the growth of C. versicolor and L. sulphureus at the level as low as 100 ppm. Further comparison of the molecular configuration of these cadinanes reveals that cadinane skeletal sesquiterpenoids with an equatorial hydroxyl group at C-9 and a trans configuration at the ring junction, such as the case for α-cadinol, exhibited the strongest antifungal activity.

On a utilise une methode de chimiluminescence sensible et selective pour detecter les radicaux hydroxyles lors de la croissance des champignons de la pourriture blanche. L'etude revele que la croissance fongique est accompagnee par la generation de radicaux hydroxyles qui a leur tour apparaissent comme responsables de la phase initiale de degradation fongique du bois.

Summary In order to reduce the leachability of boron compounds in wood, the double treatment of tetraphenylborate sodium salt [(C6H5)4BNa] (TPBNa) with potassium chloride (KCl) or tetramethylammonium bromide [(CH3)4NBr] (TMABr) was investigated by impregnating them into sapwood specimens of Japanese cedar (Cryptomeria japonica) to form insoluble salts of tetraphenylborate tetramethylammonium or tetraphenylborate potassium. The reduction of boron retention in treated wood specimens after the waterleaching test was very small, showing the good fixation of boron compounds in wood. The double treatment of TPBNa salts with TMABr or KCl solution also showed an excellent decay-resisting effect against both Coriolus versicolor and Tyromyces palustris at low boron retention.

On etudie le role du contact entre le champignon et la fibre papetiere lors du blanchiment d'une pâte kraft par le champignon de la pourriture blanche Coriolus versicolor. Les resultats indiquent qu'une liqueur microfiltree du systeme de bioblanchiment contenant C.versicolor est capable de delignifier une pâte kraft de feuillu non blanchie, mais seulement quand la liqueur est continuellement ou frequemment renouvelee par exposition au champignon.

A technique was developed to extract fungal proteins from heartwood wafers of Douglas-fir (Pseudotsuga menziesii) and sapwood wafers of red alder (Alnus rubra) colonized respectively by Postia placenta and Coriolus versicolor.

On a utilise l'essai immunoenzymatique ELISA pour detecter et quantifier les metabolites fongiques degradant le bois. La sensibilite et la specificite des anticorps produits a ete evaluee pour Postia placenta, Trametes versicolor, Lentinula edodes et Tyromyces palustris.