杉木提取物对木材腐朽菌的抑制性能

Antifungal Activities of China-Fir Heartwood Extracts Against Wood Decay Fungi

为研究杉木提取物对其耐腐性能的贡献,对杉木(Cunninghamia lanceolata)心材依次经正己烷、乙酸乙酯和甲醇常温浸泡提取,得到了3种不同的提取物。以彩绒革盖菌(Trametes versicolor)、乳白耙菌(Irpex lacte-us)、密粘褶菌(Gloeophyllum trabeum)和绵腐卧孔菌(Postia placenta)4种木材腐朽菌为供试菌,对提取物的抑菌性能进行了分析,同时以柏木脑、α-柏木烯和萘为易挥发组分模型物进行了抑菌性能分析。结果表明:3种提取物的抑菌性能不同,具有各自优势。各提取物均对采绒革盖菌有较好的抑制性能,而对乳白耙菌抑制性能较差。对比其它提取物,正己烷提取物对乳白耙菌和密粘褶菌的抑制性能更强,乙酸乙酯提取物对绵腐卧孔菌和采绒革盖菌的抑制效果更强,而易挥发组分较少、富含多酚的甲醇提取物在质量浓度为2.5 g·L-1时与乙酸乙酯提取物同样能够完全抑制采绒革盖菌。3种模型物中柏木脑和萘类的抑菌性能明显。α-柏木烯对绵腐卧孔菌和乳白耙菌不具有抑菌性能,对彩绒革盖菌和密粘褶菌有一定抑菌效果。说明杉木的天然耐腐能力是其提取物复杂的多种组分共同作用的结果。

China-fir （ Cunninghamia laaceolata） heartwood was sequentially extracted by solvents with different polarities, hex- ane, ethyl acetate and methanol, in order to get some information on the relationship of the extracts and the wood decay resistance. The antifungal activities of the extracts were evaluated against two white-rot fungi （ Trametes versicolor and lrpex /acteus ）, and two brown-rot fungi （ Postia placenta and Gloeophyllum trabeum）. The antifungal indices of cedrol, a-Cedrene and naphthalene were also tested as the model components of the volatile extracts. Different extracts presented differ- ent antifungal activities against these wood decay fungi. All extracts had good effects against T. versicolor, but low effects against/. /acteus. Among the extracts, the hexane extract presented the best activity against I. lacteus and G. trabeum, and the ethyl acetate extract against T. versicolor and P. placenta. The methanol extract, which had little volatile compo- nents and many phenols, totally inhibited T. versicolor at 2.5 g - L-1 of concentration. It was the same with that of the eth- yl acetate. Among the three model components, cedrol and naphthalene presented good antifungal activity, a-cedrene had no activity against P. placenta and I. lacteus, but had some activities against T. versicolor and G. trabeum. Therefore, many complicated components of extracts contribute the natural wood decay resistance of China-fir.