ABSTRACT
The type of basic media and the contents of plant growth substances were investigated by orthogonal design experiment,and also the effects of different culture conditions on the growth of suspension cells and the accumulation of total flavonoids in Eucommia ulmoides were studied.The results showed that B5 medium supplemented with 0.5mg/L NAA,0.6mg/L 6-BA and 30g/L sucrose,at initial pH 5.0～5.5,20g(FW)/L inoculation quantity and 110 r/min of rotation speed was a preferable culture conditions for E.ulmoides suspension cells growth and flavonoids synthesis.The results of metabolic kinetics analysis for E.ulmoides cell suspension culture showed that the logistic and Luedeking-Piret equations can be used for describing the kinetics of cell growth,sucrose consumption and flavonoids production during the process.The maximum specific growth rate(?m),the actual growth yield based on sucrose(YG) and maintenance coefficient(m) were 0.417/d,0.619g/g and 0.0206g/(g?d-1) respectively.All these outcomes could give a basis for establishing the suspension cell culture of E.ulmoides and production of the natural active components in large-scale.
ABSTRACT
In this study,nearly 200 endophytic bacteria were isolated from different part of Huperzia serrata, over 60 bacterium with clear antifungal activity were selected from those cultures.Among them,strain H-6 exhibited the highest antifungal activity which was strongly inhibits the growth of many plant pathogenic fungi such as Sclerotinia scleroliorum,Fusarium graminearumt,Sclerotinia libertiana,Phytophthora capsici Leonia and Sesame fusarium wilt.According to the characteristics of morphology,physiology and biochem- istry tests and the comparison of 16S rDNA sequence,the strain H-6 was similar to the Burkholderia.So strain H-6 was identified as Burkholderia sp.H-6.The results also showed that Burkholderia sp.H-6 was markedly different from Burkholderia cepacia that was applied widely in agriculture as antagonistic bacteria. The medium and culture conditions of the strain all were optimized by single factor and orthogonal experiments.In the investigation of the culture condition,growth was carried out in a basal medium(potato juice)and gradually supplemented with the various ingredients to be investigated.The major ingredients be- ing investigated included carbon sources and nitrogen sources.The optimal antifungal activity production condition is growth in a medium(potato juice with 2.5%mannitol and 0.1%NaNO3),initial pH 4.0 at 28℃.