Isolation And Identification Of Antimicrobial Endophytes From Pharmaceutical Plants And Optimization Of Its Ferment Factor

Endophytes are commonly found in the plants. Because of its special nature of the living environment, endiphytes and its host plants developed a symbiotic relationship. Recent years's studies show that, the endophytes have the activies substance of antibiotics, anti-tumor, pesticides, antivirus and antioxidant. This makes endophytes as an important source for people to looking for a new type of antibiotic and anticancer drug.In this scientific dissertation, some medicinal plant tissues were chosen as the materials for separation of antimicrobial endophytes, The active endophytes were indentified by physiological and biochemical techniques, and the growth conditons of Phellodendron chinense Schnei'endophyte PE-S11 were optimized. The results were as follows.1 15 sorts of plant were dealt by the optimal surface sterilization method ,which were collected from Chongqing Gele mountain, south mountain and Guiyang et al.such as Tussilago farfara L, Fagopyrum dibotrys(D.Don)Hara. And 117 strains were isolated. There were 34 strains bacterium and 83 strains fungi.But 23 of them ( 8 strains bacterium, 15 strains fungi) can't be cultivated in vitro. And most of strains fungi don't have fruiting body under our experimental condition.2 Alcoho precipitation method was used to deal with the endophytes fermentation.Amongst 94 isolates ,There were 67 endophytes which have antibacterial activities, 11 endophytes have antibacterial activities to more than 4 pathogenic microorganisms related to human disease, and 3 endophytes have antibacterial activities to 10 .They were TE-R7, FE-R9 and PE-S11,isolated from Tussilago farfara L, Fagopyrum dibotrys(D.Don)Hara and Phellodendron chinense Schnei .3 Refer to Fungus Idemtofocatopm Manual and Fungi taxonomy, Through training patterns, microscopic observation, 18S rDNA of isolate three endophytes were sequenced. Found that, TE-R7 was 99% homology to fusarium oxysporum f.cubense(EF590328) and 98%-99% homology to other Fusrium sp.According to the result, TE-R7 belong to Fusrium sp . different fungus of fusarium oxysporum f.cubense.FE-R9 was 100% homology to fusarium oxysporum and 98%-100% homology to other Fusrium sp.According to the result, FE-R9 belong to fusarium oxysporum . PE-S11 was 98% homology to Nectria sp. GD507 and 96%-98% homology to other Netria. According to the results , PE-S11 may be one fungus of Nectria sp.During the condition of our laboratory.4 The optimum ferment condition of Nectria sp.Strain PE-S11 is PDA , 27℃, PH 6.0-7.0, 120r/min,30% Medium volume, 2% glucose (or sugar), 0.3% peptone, 7-9d , Deal with the endophytes fermentation, Nectria sp.Strain PE-S11 was stabilized inhibitory effect basicly to 6 pathogenic microorganisms. Optimization training, help stabilizing the strain PE-S11 of the inhibitory effect.