| Cancer is the second biggest disease in the world. Based on statistics of U. S. National Cancer Institude (NCI), the death toll is 6, 700, 000 in 2002 and the number will rise to 10, 300, 000 in 2020.At the same time, many anticancer drugs are being discovered and developed. Taxol is one of the most powerful anticancer drugs for its wide usefulness. The mechanism is that taxol binds to tubulin and inhibits the disassembly of microtubules, thereby resulting in the inhibition of cell division. Meanwhile it also induces apoptosis by binding to and blocking the function of the apoptosis inhibitor protein Bcl-c (B-cell Leukemia 2).Taxol has continuously made a magic sale tale for 15 years, since it comed out in market in January 1993. It averagely brought 1.035 billion dollars every year for Bristol-Myers-Squibb during its patent phase and in 2000 it got to the top, selling 1. 592 billion. According to U. S. NCI estimation, in 2007 the global taxol quantity demanded will exceed 5000 kg, which is nearly 15 times of the annual output (350 kg) in 2001. It shows that as there is a big gap between quantity demanded and quantity supplied in taxol market, taxol's market room is huge.The key to settle the problem of taxol shortage is to develop a better way to produce taxol continuously, rapidly, commercially. Nowadays, the ways, which have reached the commercial production requirements, are directly getting taxol from the bark of yew tree and semi-synthesis. Both of them have a great dependence on the plant, and could bring serious damage to ecological environment. Even more, separation and purification of taxol or its precursors from plant is very complicated, and the cost is really high. As a result, finding a quick, effective method to producing taxol is very important.Taxol-producing microbes fermentation is the most potential method among so many new ways. There are four reasons: 1. fermentation technology is mature; 2. microbes grow and breed quickly; 3. it is probable to use traditional methods or gene engineering to improve microbes to get more taxol; 4. microbes are rich resources. Endophytic fungi widely exist in different parts of each plant, and most of them get the ability to produce the same or similar compounds. There are 4 species and 1 var. yew trees in China, among which Taxus Chinensis var. mairei contains taxol comparely higher. From now on, more than 30 taxol-producing fungi have been found in the world, but the quantity of taxol is too low to get into industrial production. Continuing sreaching high production microbes is still very necessary.This article using Taxus Chinensis var. mairei and its endophytic fungi as material seperated 30 endophytic fungi. They separately belong to Alternaria, Aspergillus, Mucor, Stroptothrix, Periconia, Aspergillius niger, Oidiodendron, et al. Through TLC and HPLC assays, we found 1 fungus, XH4, which could produce taxol at a high level (430. 46μg/L).Combining morphologic and ITS-5.8S rDNA sequence identification methods, XH4 was conformed to be Bionectria sp.. This was a new recorded-species in Taxaceae endophytic fungi, which enlarged the range of Taxaceae endophytic fungi.In order to get more uselful compounds of XH4, we did deeper research in the separation of its metabolites, and analyzed each component by anti-microbe and cytotoxicity tests. The result of anti-microbe assay indicated that XH4's metabolites had distincty inhibitive activity to Candida albicans, Staphylococcus aureus and Bacillus subtilis, especially to Candida albicans, but had no effect on Escherichia coli and Pseudomonas aeruginosa. The result of cytotoxicity assay indicated that XH4's metabolites had strong activity to kill HeLa cell.It is a new beginning of the way to produce taxol by microbes that 1 taxol-producing fungus has been found in our research. It adds new content in Taxaceae endophytic fungi that studing on the diversity of endophytic fungi. It provides a preparation to discover new antimicrobe or anticancer drugs that doing more research on the metabolites of endophytic fungi.
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