Pycnoporus sp. SYBC-L1 18S rDNA序列分析及其固态发酵水葫芦产漆酶的研究

18S rDNA Sequence Analysis of Pycnoporus sp. SYBC-L1 and Studies of Laccase Production on Hyacinth Solid-state Fermentation

从朽木上筛选到一株产漆酶的白腐真菌SYBC-L1,该菌株在PDA-Guaiacol培养基上显红色,通过18S rDNA序列测定和进化树聚类分析,表明其属于密孔菌属,命名为Pycnoporus sp. SYBC-L1。以水葫芦为基本培养基质,以漆酶活力为指标,对其产酶培养基进行了初步优化,得其适宜的培养基为:水葫芦12.5%,可溶性淀粉与豆粕质量比1∶1,起始含水量65%,Cu2+浓度1.5mmol/L,没食子酸20μmol/L,30℃,培养9d,漆酶活力可达19.17U/g,为优化前的8.75倍。Pycnoporus sp. SYBC-L1漆酶提取的适宜条件为:20mmol/L,pH6.0的磷酸盐-柠檬酸缓冲液,浸提3h。

A new laccase - producing fungus SYBC-L1 was isolated from a rotten wood. The strain appeared red color around the margin of colonies on PDA-Guaiacol plate. According to the 18S rDNA sequence analysis, the strain SYBC -L1 was proved to belong to genus Pycnoporus and identified as Pycnoporus sp. SYBC -L1. The laccase producing factors of Pycnoporus sp. SYBC-L1 was optimized by using solid - state fermentation. The results showed the optimal medium was as follows： hyacinth 12.5% , soluble starch and soybean meal with a ratio of 1：1, water content 65% , Cu2. 1.5 mmol/L and gallic acid 20 μmol/L. After 9 days of cultivation at 30 ℃ , the maximum laccase activity was determined to be 19.17 U/g, which was 8.75 folds than that in basal medium. The laccase of Pycnoporus sp. SYBC-L1 was extracted with citrate/Na2HPO4 buffer （20 mmol/L, pH 6.0） for 3 h.