China-fir (Cunninghamia lanceolata) wood is well known for its good durability. This species is native to China and has been extensive planted there. Mainly, extractives are responsible for the wood resistance to decay fungi. In this paper, the extractives of China-fir heartwood were studied for their effects on various wood decay fungi. Sequential extraction of heartwood in hexane, ethyl acetate and methanol resulted in 0.8, 1.0 and 2.8 % (w/w) recoveries, respectively. Both of fourier transform infrared spectroscopy (FTIR) analysis and high performance liquid chromatography (HPLC) analysis revealed that hexane extractives were primarily aliphatic compounds, methanol extractives were mainly phenolic in nature and ethyl acetate extracts contained both aliphatic and aromatic compounds. Gas chromatography-mass spectrometry (GC-MS) analysis clarified that cedrol and cedrol acetate represented approximately 47 % of the hexane extract. Phenol content analysis showed that phenols took up 22.8% of the methanol extract and the extract’s free radical scavenging capacity was close to that of butylated hydroxytoluene (BHT), which is a commercial antioxidant. In vitro bioactive tests showed that none of the three extracts were strongly inhibitory to cultures of Trametes versicolor, Gloeophyllum trabeum, Aspergillus niger or Paecillomyces variotii. These results suggest that the combination of extractive fractions rather than any single compound, is important for China-fir durability. Soil block tests showed that non-extracted heartwood blocks were resistant to T. versicolor but experienced substantial weight loses when exposed to G. trabeum. Weight losses increased in hexane extracted blocks, but then declined markedly in those ethyl acetate extracted blocks. The results suggest that either residual solvent in the material inhibited the white rot fungus or the extraction process altered available phenol content to limit the ability of the fungus to attack wood.

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