| In order to find new resources for novel drugs and new way to improve the quality of herbal materials, plant chemistry, endophytic fungi and their secondary metabolites in the bark, branches and leaves of Taxus chinensis var. mairei from the Jiangxi, Zhejiang and Chongqing regions of China were mainly studied. The results were showed as follows.T. chinensis var. mairei from three localities (Jiangxi, Zhejiang and Chongqing in China) harbours high and novel diverse fungi. A total of2442strains were isolated from bark, branches and leaves of T. chinensisvar. mairei at three localities. A total of145fungal taxa were identified according to the morphology and ITS sequences, of these125taxa (86.2%) belonged to Ascomycota,14(9.7%) to Basidiomycota,5(3.4%) to Zygomycota and1(0.7%) to undefined fungus. The species richness and diversity of endophytic fungi were significantly affected by tissue, and were1.2-3fold higher in the branches and bark when compared to the leaves.The shape of the endophyte assemblages were strongly influenced by locality and tissue. In addition, the distributions of dominant fungi at different taxonomic levels including orders, genera and species levels were greatly influenced by locality and tissue. Hypoxylon was the dominant genus in Zhejiang, and Pezicula and Pestalotiopsis were the dominant genera in Jiangxi and Chongqing. Among the145fungi,10taxa shared among the three localities,20taxa occurred at two localities, and the others were special to one locality. The most dominant orders i.e. Magnaporthales, Botryosphaeriales, Glomerellales, Diaporthales, Xylariales, Helotiales, Hypocreales and the most dominant genera Phyllostictal Guignardia, Colletotrichuml Glomerella, Phomopsis, Hypocreal Trichoderma, Pezicula showed obvious tissue-specificity. Most of the dominant fungi showed spatial heterogeneity and tissue specificity or preference and many fungal taxa with low frequency were special to one locality or one tissue. More fungal taxa could be obtained in T. chinensis var. mairei as functions of locality and tissue. These endophytic fungi are important material sources and are currently being investigated by our laboratory for bioactive substances which can be screened for novel drugs.HPLC for determining the contents of taxol and10-DAB Ⅲ combined with HPLC-TOF/MS data analysis on the chemical compositions were applied to compare the differences in the chemical compositions of yew trees among the localities or tissues. The results showed that taxol and10-DAB Ⅲ were both found to be significantly different in quality between tissues and across the localities. The levels of taxol and10-DAB III in yew trees from Jiangxi both were the highest. At each locality, the leaf contained the highest concentration of10-DAB Ⅲ while the bark contained the highest concentration of taxol.The chemical compositions in plants of T. chinensis var. mairei were extremely complex,148compounds were preliminary identified including the taxanes, the abietane, lignan and so on. The chemical compositions among tissues were significantly different. This result was agreed with the difference in the distributions of domiant fungi among tissues. According to PLSDA analysis on TOF mass data,18compounds with great difference among tissues were selected. Of them,11compounds including8taxane diterpenoid (P2, P5-P7, N1, N2, N7-N9),2lignans (N3, N5), and abietane diterpenes (N6) were preliminary identified by comparing to chemical composition database of T. chinensis var. mairel.The relationships between the18selected compounds and endophytes assembleges were further studied. The result that these compounds were related to the distribution of some endophytic fungi with tissue-specificity indicated that endophytic fungal compositions and chemical compositions were related. There was a significant correlation between the levels of active ingredients (taxol and10-DAB Ⅲ) and the distribution of some endophytic fungi especially the dominant groups. Several dominant fungi at different taxonomic levels were significantly related to the content of taxol, e.g. Helotiales, Hypocreales and Xylariales at order level, Hypocrea and Pezicula at the genus level, and Hypocrea lixii at the species level. Also, several dominant fungi at different taxonomic levels were significantly related to the content of10-DAB III, e.g. Botryosphaeriales, Magnaporthales at order level, Fusarium/Gibberella and Phyllosticta/Guignardia at genus level and Colletotrichum gloeosporioides, Glomerella lindemuthiana, Magnaporthales sp.2and Xylariales sp.l at species level. The relationships between RF of these mentioned dominant fungi and the content of taxol or10-DAB III were all fit to the Cubic Model. Clarified the influences of endophytic fungi on the quality of medicinal plants (the levels of active ingredients) has important theoretical value and practical significance in improving the quality of medicinal plants and screening high-quality medicinal plants. Based on bioactivity and comparative analysis on chemical composition, the EtOAc extract of a culture broth of the endophytic fungus Perenniporia tephropora Z41, with strongest anti-Pyricularia oryzae activity and largest number of similar compositions with the host, afforded a new sesquiterpenoid, perenniporin A (1), together with four known compounds, ergosterol (2), rel-(+)-(2aR,5R,5aR,8S,8aS,8bR)-decahydro-2,2,5,8-tetramethyl-2H-naphtho[1,8-bc]furan-5-ol (3), albicanol (4) and para-methoxybenzoic acid (5). Their structures were elucidated by means of spectroscopic methods. All the isolated compounds and the EtOAc extract of Perenniporia tephropora Z41(EPT) were evaluated for their cytotoxic activity against three human cancer cell lines (HeLa, SMMC-7721and PANC-1). EPT demonstrated significant cytotoxicity with IC50values ranging from2to15μg/mL. Compound2was the most cytotoxic constituent against the tested cell lines with IC50values of1.16,11.63and11.80μg/mL, respectively, while compounds1,3,4and5exhibited moderate cytotoxicity with IC50values ranging from6to58μg/mL. Our results indicate that sesquiterpenoids1,3, and4could be valuable candidates as potent tumor inhibitors and be beneficial in the therapy of cancer diseases. Our study also underscores that endophyte P. tephropora is a promising sources of natural bioactive and novel sesquiterpenoids metabolites, though without diterpenoids like taxols.
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