[Isolation of endophytic fungi from Zanthoxylum simulans and screening of its active strain]

This study aims at making full use of microbial resources, and screening the active endophytic fungi of anti-rheumatoid arthritis from Zanthoxylum simulans. The endophytic fungi were cultured and isolated by tissue culture and scribing method, and the active strain of inhibiting the proliferation of human rheumatoid arthritis synovial fibroblasts (HFLS-RA) was screened by MTT method. Morphological characteristics and rDNA ITS1-5.8S-ITS2 sequences were applied for the taxonomy of endophytic fungi. Strains were isolated from Z. simulans. Among them, MK-05, MK-17, MK-19, MK-23 having inhibiting activity to HFLS-RA, the IC₅₀ were 0.367, 0.775, 0.689, 0.757 g·L⁻¹, respectively. By classic morphologic classification and sequencing the PCR-amplified rDNA ITS1-5.8S-ITS2 regions, four effective strains were identified as Botryosphaeria dothidea, Phomopsis sp., P. liquidambari and Diaporthe perseae. The active endophyic fungi that inhibited the proliferation of HFLS-RA were screened from Z. simulans for the first time, and the results lay the foundation for the development and utilization of the Z. simulans resources.