| Endophyte is special microbiology that resides in tissues of living plants. They generally exist the studied plants and are able to produce the same or the similar bioactive substances. Screening endophytes with antagonistic activity develop a new way for finding new bioactive substances. Mushrooms are delicious food and good medicine. As far the reports about mushroom endophytes are relatively small and the major question is whether the wild mushrooms that are difficult to manual cultivation has relationship with a microorganism in carpophore.In order to exploit the resource of mushroom endophytes, and find the endophytes that were able to produce the same or the similar bioactive substance with mushroom. In order to understand the relationship among the the number of endophytes, the cultivated modes of kinds of mushrooms and the separation methods. In this experiment, carpophore of Agaricus bisporus, Lentinus edodes, Plteurotu comucopiae, Flammulina velutipes, Agaricus bisporus and Agrocybe cylindracea were used as materials. Mushroom endophytes were separated by abrative method, tissue explant and blotting method. So that the diversity and ecological sisttibution laws were found. The reaserch screened endophytes with great antimicrobial activity by abrasive method from carpophore of Agaricus bisporus. And their classification and antagonistic substances were studied. The main results were given as follows:1. Fifty-eight endophytes from fruiting body of six mushrooms were separated using abrasive method, the amount from Agaricus bisporus, Lentinus edodes and Pleurotus comucopiae was respectively 27, 19, and 12. Others have not separated. Fifteen strains showed bacteriostasis activity, which was 29%of total strains; nine strains were from Agaricus bisporus, four trains were from Lentinus edodes, two trains were from Plteurotu comucopiae. Twenty-one endophytes from carpophore of six mushrooms were separated using tissue explant, the amount from Agaricus bisporus, Lentinus edodes and Plteurotu comucopiae was respectively12, 3, 6. Others have not separated. There was not endophyte strains separated using blotting method. The results of the strain antagonistic experiment and the sterile-filtered supernatant showed that AB-114 had the strongest antagonistic activity against Escherichia coli, Staphylococcus aureus, yeast, Trichoderma spp. Especially to Escherichia coli, yeast, Trichoderma spp, the all inhibitory diameters reached 15mm. so the strain AB-114 had great capacity of research and application.2. According to the characteristics of morphological feature, physiology, biochemistry tests and the comparison of 16SrDNA sequence, the classification of the strain AB-114 was established. The results showed that the strain had a widely scope of the pH, but mostly cannot live under 5.0. The optimal pH and temperature were respectively 7.0, 30℃. And the fatal temperature was 70℃. The strain was aerobe. It can ferment glucose, hydrolyse amylum, utilize citrate and malonate, deacidize nitrate, and so on. The 16SrDNA sequence of AB-114 strain was 1440 bp, which had 99% sequence similarity with Pseudomonas. According to the phylogenetic tree, The AB-114 strain was identified as a strain of Pseudomonas.3. The bioactive substances of AB-114 strain were extracted by organie solvents precipitates and solvents extraction. The extraction effect of organie solvents precipitates had showed better effection than solvents extraction, but the consumption of organic solvent was large. Solvents extraction was adopted to extract the bioactive substances of the strain AB-114.Based on TLC, silica gel plate chromatography, bioassay-guided isolation and HPLC, two components with the greatest antimicrobial activity and the largerest content were obtained. The result of the colour reaction indicated that the active substances were Alkaloids.
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