Sun Duanfang, Ran Xueqin, Wang Jiafu
Faculty of Animal Science, Guizhou University, Guiyang 550025, China.
Wei Sheng Wu Xue Bao. 2008 May;48(5):589-95.
Endophytic fungi can produce beneficial active components during symbiosis with host plants. We isolated a taxol-producing endophytic fungus strain from Podocrapus.
The anti-tumor activity of the endophytic funguswas detected by Methyl Thiazolyl Tetrazolium (MTT) method with Vero cells. The production of taxol by one fungus was confirmed by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). This strain was classified by morphology together with similarity of internal transcribed spacer (ITS) sequence by Clustal W method. The deduced apoptosis of taxol produced from the strain was detected by fluorescent staining method with Vero cells.
A total of 155 endophytic fungi were isolated from the tissue of Podocrapus. The result showed that 28 strains inhibited the growth of Vero cell (inhibitory ratio > or = 10%), and 7 strains had high activity (inhibitory ratio > or = 70%). The taxol-producing ability of strain A2 was confirmed by TLC and HPLC. Therefore, we recognized strain A2 as an endophytic fungus capable of producing taxol from Podocrapus-1 and named it EPTP-1. Its output of taxol was 0.56 mg/L when growing in liquid potato dextrose medium. EPTP-1 was classified as Aspergillus fumigates. Taxol extracted from strain EPTP-1 resulted in significant apoptosis of Vero cells at concentration of 5.553 microg/L for 24h. The activity of anti-Vero growth by extracts from strain EPTP-1 was similar to that of the purchased standard taxol (P > 0.05).
The identified endophytic fungus, strain EPTP-1, can be a candidate for taxol production.
内生真菌在与宿主植物共生过程中可产生有益的活性成分。我们从罗汉松中分离出一株产紫杉醇的内生真菌菌株。
采用甲基噻唑基四氮唑（MTT）法，以Vero细胞检测内生真菌的抗肿瘤活性。通过薄层色谱法（TLC）和高效液相色谱法（HPLC）确认一株真菌产生紫杉醇的情况。通过形态学分类，并采用Clustal W方法分析其内部转录间隔区（ITS）序列的相似性，对该菌株进行分类。采用荧光染色法，以Vero细胞检测该菌株产生的紫杉醇诱导凋亡的情况。
从罗汉松组织中共分离出155株内生真菌。结果显示，28株菌株抑制Vero细胞生长（抑制率≥10%），7株具有高活性（抑制率≥70%）。通过TLC和HPLC确认了菌株A2产生紫杉醇的能力。因此，我们将菌株A2认定为从罗汉松-1中分离出的一株能够产生紫杉醇的内生真菌，并将其命名为EPTP-1。其在液体马铃薯葡萄糖培养基中生长时，紫杉醇产量为0.56 mg/L。EPTP-1被归类为烟曲霉。从菌株EPTP-1中提取的紫杉醇在浓度为5.553 μg/L作用24小时时，可导致Vero细胞发生明显凋亡。菌株EPTP-1提取物对Vero细胞生长的抑制活性与购买的标准紫杉醇相似（P>0.05）。
鉴定出的内生真菌菌株EPTP-1可作为生产紫杉醇的候选菌株。
