香灰菌与银耳混合培养过程中酶系的相互作用

Interaction Rules of Enzyme System between Hypoxylon sp.and Tremella fuciformis

该实验对纯香灰菌(Hypoxylon sp.)培养及其与银耳(Tremella fuciformis)混合培养过程中的纤维素酶、淀粉酶、漆酶等培养原料基质降解相关酶变化规律进行了比较与分析。结果表明,香灰菌长满菌袋后淀粉酶与漆酶活力随着培养时间的延长逐渐下降,木聚糖酶活力在培养至15 d达到最大值5 000 U·m L-1,纤维素酶活力培养至5 d后,稳定在40 U·m L-1左右,可以有效降解木料培养基。银耳与香灰菌混合培养后,在固体培养过程中,其中胞外可溶性蛋白浓度和木聚糖酶、纤维素酶活力变化规律与香灰菌纯培养相似,而淀粉酶在培养至第10天达到最大值2 253 U·m L-1,其胞外可溶性蛋白浓度与木聚糖酶、纤维素酶和淀粉酶活力显著提高,漆酶活力培养至第5天达到最大值71.33 U·m L-1,随后迅速下降,蛋白酶活力变化情况与淀粉酶相似,第15天酶活力达到最大值3.05 U·m L-1。说明混合培养中两者具有互作效应,可以有效促进胞外蛋白的分泌,提高基质降解相关酶活力,促进菌体对基质的降解,提高养分的供应。该结果可为银耳优良菌种的选育,两者的配比以及栽培料的选择与优化提供科学依据。

In order to study the interaction rules of enzyme system between Hypoxylon sp. and Tremellafuciformis, the substrate degradation related enzymes about the Hypoxylon sp. and mixed strain cultivation （T. fuc/form/s and Hypoxylon sp.） were de- termined and analyzed. The results showed that the amylase and laccase activity of Hypoxylon sp. reduced during the culture period. However, the activity of xylanase reached the peak of 5 000 U mL-1 at the 15th day, while the cellulase activity increased and reached the peak of 40 U mL-1 after the 5th day, which could degrade the wood culture medium effectively. The changing rule of soluble extracellular protein concentration, xylanase and cellulase in medium by mixed strain cultivation had similar trend with Hypoxylon sp., while the amylase reached the peak of 2 253 U mL-1 at the 10th day and soluble extracellular protein concentration and xylanase, cellulose, amylase activity increased obviously. The laccase activity reached the peak of 71.33 U mL-1 at the 5th day and then declined sharply. The changing rule of proteinase activity was similar with amylase which reached the peak of 3.05 U mL-1 at the 15th day. The results indicated that the interaction in mixed strain cultivation not only promote the secretion of extracellular protein, but also it improve the substrate degradation related enzyme activity, and increase the ability of degradation for the substrate. The results lay good foundation for the T. fuciformis breeding, such as the ratio and the culture medium for the Hypoxylon sp. and the T. fuciformis.