【作者】 吴敏；

【导师】 何少云；

【作者基本信息】 华南农业大学 ， 观赏园艺学， 2016， 硕士

【摘要】 目前,许多严重威胁人们生命健康的疾病缺乏有效的防治药物,不断研究和创制新的优良药物成为了我国人口与健康领域的紧迫需求。迄今临床应用的药物1/3以上直接来自天然产物或以天然产物的活性成分为先导物进一步开发的衍生物,这使得从天然产物中发现活性先导化合物成为了获得创新药物的重要途径。植物内生真菌是发现天然产物的重要来源,其具有丰富的代谢产物,其中包括一些新物质或新骨架,具有特殊生物活性。其中,炭角菌是大量生物活性物质的来源,其代谢产物中包括抗菌、抗肿瘤、抗氧化等多种活性的结构新颖化合物,对其进行研究有望发现最具药用开发前景的天然产物,具有较高的理论和实践意义。本研究以植物内生炭角菌Xylaria sp.G-10为基础材料,通过发酵、萃取、浓缩、分离纯化、化合物结构鉴定以及活性研究,得到以下研究成果:1.将炭角菌发酵萃取后,采用常规的硅胶柱层析、葡聚糖凝胶LH-20柱层析、制备薄层层析(pTLC)、重结晶以及高效液相色谱(HPLC)等分离手段,分离纯化得到单体化合物。综合运用现代波谱技术鉴定出9个化合物,其中两个为大环内酯类化合物:ZHY-1(A8)和2H-Oxecin-2-one,10-heptyl-3,4,5,8,9,10-hexahydro-5,8,9-trihydroxy-(A9),一个倍半萜类化合物ZHY-2(A12),三个异二氢香豆素类化合物(A1、A2和A6),一个麦角甾醇类化合物(A4),L-色氨酸(A3)和3-吡啶甲酸(A5)。2.对化合物A4、A6、A8、A9和A12进行抗革兰氏菌活性测定,结果表明:A6、A8、A9和A12均对金黄色葡萄球菌(G+)有明显的抑制作用;采用红火蚁胃毒法和二斑叶螨浸叶法对A12的粗提物进行杀虫活性的测定,结果表明:A12的粗提物对红火蚁具有较好的毒力作用,受药48h后,1000ppm、500ppm和250ppm药剂浓度下的红火蚁的校正死亡率分别为(60.00±5.77)%、(31.67±1.67)%和(30.00±2.89)%;对化合物A8、A9和A12进行细胞毒活性的测定,结果表明:三个化合物对HepG2、SKOV3和MCF-7均有微弱的抑制作用。本论文通过对植物内生炭角菌Xylaria sp.G-10代谢产物的化学结构和生物活性的研究,为它们作为植物源杀虫剂和微生物药物的进一步研究和开发提供了理论依据,具有重要的参考价值。更多还原

【Abstract】 Many serious diseases threatened people`s lives and health for lack of effective drugs currently, so continuing to study and create new drugs has become the urgent need of our population and health field. So far more than 1/3 of the clinical application of drugs was from natural products or derivatives developed by active ingredients of natural products as guides, which made discovering active leading compounds from natural products become an important access to inventing new drugs. Endophytic fungi is the important source to find natural products, and it has a wealth of metabolites including some new material or new framework which have special biological activity. Xylaria fungus is the source of a large number of biologically active substances, which include antimicrobial,antitumor, antioxidant and other novel compounds. It is expected to find the most development prospect of medicinal natural products to research with high theoretical and practical significance.This study was based on endophytic fungus Xylaria sp. G-10, which is one of the plant endophytic Xylaria sp. as material to get the following results through fermentation,extraction, concentration, isolation, purification and identification of compound structure.1.After extracting Xylaria fermentation, compounds was purified by using conventional silica gel column chromatography, LH-20 dextran gel column chromatography, thin-layer chromatography of preparation(p TLC), recrystallization and high-performance liquid chromatography(HPLC) and other separation methods. There are 9compounds identified by modern spectroscopic,which include two macrolide compounds:ZHY-1(A8) and H-Oxecin-2-one,10-heptyl-3,4,5,8,9,10-hexahydro-5,8,9-trihydroxy-(A9),a sesquiterpene compound ZHY-2(A12), three dihydrocoumarins, a ergosterol(A4),L-Tryptophan(A3) and Nicotinic acid(A5).2.Anti gram bacteria experiments were developed on A4、A6、A8、A9 and A12, and the result showed that A6, A8, A9 and A12 significantly inhibite Staphylococcus aureus(G+). Determination of insecticidal activity experiment was developed on A12 using the ants stomach poison method and the two spotted spider mite leaf dipping method, and the results showed that after receiving drug 48 hours,crude extract of A12 has a good role in virulence, and the corrected mortality of ants are respectively(60.00±5.77)%,(31.67±1.67)% and(30.00±2.89)% under the reagent concentration of1000 ppm,500ppm,250 ppm. Determination of toxicity experiments were taken on A8、A9and A12,and the results showed that these compounds have a weak inhibitory effect on Hep G2, SKOV3 and MCF-7.In this paper,the studies of chemical structure and bioactivity for endophytic fungus Xylaria sp. G-10 were conducted. These results provide a theoretical basis for the further research and development of endophytic fungus Xylaria sp. G-10 which were regarded as botanical insecticide and microbial drugs.更多还原