内生细菌及其组合对雷公藤悬浮细胞生长及生化特性的影响

Effects of Endophytic Bacteria and the Mixtures on Growth and Biochemical Properties of Suspension Cells of Tripterygium wilfordii

本研究将雷公藤内生细菌菌株PseudomonaschlororaphisLG6、PantoeaananatisLY3、Bacilluscereusgroup LJ3、BacilluscereusgroupLJ12及其组合分别以活菌、灭活菌体粗提物和菌液的形式添加到悬浮细胞培养体系中,通过检测悬浮细胞的重量、细胞活力以及培养液的pH、电导率、可溶性糖和NO3-含量,分析了内生细菌对雷公藤悬浮细胞生长状况的影响。结果显示,内生细菌活菌对悬浮细胞生长的影响较大,菌株LY3、LJ3、LJ12、LY3+LJ12及LG6+LY3+LJ3+LJ12活菌对悬浮细胞的鲜重具有促进作用,菌株LY3和大部分混合菌株的活菌降低了培养液的pH,多数内生菌株活菌提高了培养液的电导率,内生菌株活菌的添加使培养液的可溶性糖含量发生了较大变化,并明显提高了培养液中的NO_3^-含量。灭活菌体粗提物和菌液的添加对细胞鲜重的增加多表现为抑制作用。

In this study, endophytic bacterial strains Pseudomonas chlororaphis LG6, Pantoea ananatis LY3, Bacillus cereus group LJ3, Bacillus cereus group LJ12 isolated from Tripterygium wilfordii and their mixtures were made into living strains, crude extracts of dead thallus and bacterium solution, and then were added into the culture systems of plant suspension cells. The growth status of suspension cells after the addition of endophytic strains were analyzed by examining fresh weight and activity of suspension cells, pH value, electrical conductivity, soluble sugar and NO3-content of culture media. The results indicated that the living endophytic strains had a great effect on the growth of suspension cells. Living strains of LY3, LJ3, LJ12, LY3＋LJ12 and LG6＋LY3＋LJ3＋LJ12 promoted cell fresh weight compared to the control. The living strains of LY3 and majority of mixtures decreased pH values of the culture media. Compared to those of the control, the electrical conductivity of the culture media treated by adding most of the living strains increased. The living endophytic strains were also found to change soluble sugar content and increase NO3-content of the culture media compared to the control. Different from the living strains, the crude extracts of the dead thallus and bacterium solution disturbed the cell growth and decreased cell fresh weight compared to the control.