简青霉(Penicillium simplicissimum)对木质纤维素的降解及相关酶活性特征

简青霉Penicillium simplicissimum(Oudem.)Thom BGA]能分泌木质纤维素降解酶,其中半纤维素酶、纤维素酶、木质素过氧化物酶、锰过氧化酶和漆酶的最大酶活分别为146.82 Iu·g-1、2.78 U·g-1、47.97 U·g-1、34.56 U·g-1和17.94 U·g-1.实验结果和SPSS统计分析表明,简青霉产木质纤维素酶的能力与木质纤维素的结构有很大的关系,其对木质纤维素的降解可能是几种木质纤维素酶之间协同作用的结果.在30 d的固态发酵中,半纤维素含量与发酵天数呈显著负相关(r=-0.946,P<0.01),纤维素与木质素的降解趋势呈显著负相关(r=-0.818,P<0.05).木质素过氧化物酶和锰过氧化物酶在降解木质素的同时对半纤维素和纤维素进行协同降解,是非选择性的木质素降解酶.木质素过氧化物酶、锰过氧化物酶与纤维素酶之间呈显著相关(相关性依次为r=0.922,P<0.01;r=0.807,P<0.05).研究还发现生物吸附在简青霉对液态碱木质素的去除中起到了非常重要的作用.

Biodegradation of Lignocellulose by Penicillium simplicissimum and Characters of Lignocellulolytic Enzymes

Penicillium simplicissimum(Oudem.)Thom BGA can secrete lignocellulolytic enzymes, among these enzymes the highest activities of hemicellulase, cellulase, lignin peroxidase(Lip), manganese peroxidase(Mnp) and laccase are 146.82 Iu·g^-1, 2.78 U·g^-1, 47.97 U·g^-1, 34.56 U·g^-1 and 17.94 U·g^-1 respectively. According to the results and the statistical analysis of SPSS, the ability of secreting lignocellulolytic enzymes by Penicillium simplicissimum significantly correlated with the structure of lignocellulose, and the biodegradation of lignocellulose was probably a kind of synergistic effect of several lignocellulolytic enzymes. In the solid-state fermentation of 30 days, the hemicellulose content has a significantly negative correlation with the fermentation days(r=-0.946, P<0.01), there was also a significantly negative correlation between the cellulose-biodegradation and the lignin-biodegradation(r=-0.818, P<0.05). As unselected enzymes, Lip and Mnp can degrade hemicellulose and cellulose corporately when biodegrades lignin. The significant correlation is showed between Lip, Mnp and cellulose (correlation parameters are r=0.922, P<0.01; r=0.807, P<0.05 respectively). In addition, the biosorption is found to have a very important effect in the removal of liquid alkali lignin by Penicillium simplicissimum.