白腐真菌预处理对柳枝稷降解的影响

Effects of Pretreatment of White-rot Fungi on Degradation of Switchgrass

试验用黄孢原毛平革菌(Phanerochaete chrysosporium)、乳白耙菌(Irpex lacteus)、虫拟蜡菌(Ceriporiopsis subvermispora)3种白腐真菌及其混合菌对柳枝稷进行预处理,研究白腐真菌种类、时间、温度、水分、菌液量对柳枝稷降解的影响,为柳枝稷的生物预处理及利用提供理论依据。结果表明:黄孢原毛平革菌、乳白耙菌和虫拟蜡菌两两之间均无拮抗反应,可以相互混合生长;当温度为28°C,加水5mL,菌液量为1mL时,混合真菌对木质素的降解与单一白腐真菌相比并没有优势,在3种白腐真菌中,乳白耙菌效果最好,几乎不降解纤维素,并且在第20天时木质素降解率达到最高为36.63%;当改变条件时,发现温度为28°C,水分为5mL,菌液量为3mL是乳白耙菌对柳枝稷进行预处理20d效果最好的条件,此时木质素降解率最高为63.45%,半纤维素降解率为24.82%,而纤维素和空白组差异不显著。因此,在三种白腐真菌中,乳白耙菌对柳枝稷的预处理效果最好,木质素降解率最高,半纤维素略有降解,而且几乎不降解纤维素。

The effect of three kinds of white-rot fungi（Phanerochaete chrysosporium,Irpex lacteus,Ceriporiopsis subvermispora）and their mixture on switchgrass（Panicum virgatum L.）biomass degradation were studied in this experiment.The fungi species,time and pretreatment controlled condition（temperature,additional liquid volume of fungi and water content）were compared during the pretreatment period to figure out the perfect condition for switchgrass biomass degradation by white-rot fungi addition.The results were as follows：In antagonistic experiment,we observed Phanerochaete chrysosporium,Irpex lacteus and Ceriporiopsis subvermispora growed well when they mixed with each other;When the temperature was 28°C,water was 5 mL and additional liquid volume of fungi was 1 mL,the degradation of lignin by single fungi addition was not inferior to fungi mixture addition and pretreatment effect of switchgrass by Irpex lacteus alone was the best among the three fungi,whose maximum lignin degradation rate reached36.63% after 20 days;We found that the highest lignin degradation rate reached 63.45%,hemicellulose degradation was 24.82%,and cellulose degradation had no significant difference from blank group,when temperature was 28°C,water was 5 mL,and additional liquid volume of fungi was 3 mL,which was the best condition for switchgrass pretreatment by Irpex lacteus.These data indicated that pretreatment effect of Irpex lacteus on switchgrass was the best,whose lignin degradation rate reached maximum,hemicellulose was slightly degraded and cellulose was hardly degraded.