紫锥菊不定根悬浮共培养中咖啡酸衍生物积累研究

Research on The Caffeic acid Derivatives Accumulation of The Co-cultured Echinacea Adventitious Roots

为筛选出紫锥菊不定根共培养最佳组合及其接种量,以紫松果菊(Echinacea purpurea,Epu)、白色紫锥菊(Echinacea pallida,Epa)和狭叶紫锥菊(Echinacea angustifolia,Ean)3种药用紫锥菊不定根为材料,在500 m L三角瓶中加入200 m L的0.5 MS+1.0 mg/L IBA培养基进行了悬浮培养,调查了接种量5 g/L、7 g/L和10 g/L及不定根组合方式对共培养紫锥菊不定根生物量、次生代谢产物积累及抗氧化活性的影响。结果表明,接种量为7 g/L时的Epa+Epu共培养不定根干重(6.75 g/L)最高,此组合中不仅多酚(40.31 mg/g DW)和黄酮(34.29mg/g DW)含量高,其产量(多酚272.09 mg/L,黄酮231.46 mg/L)也最高。紫锥菊不定根共培养组合中,只有Epa+Epu不定根中6种咖啡酸衍生物都具有,而且此共培养不定根还刺激产生Epa和Epu单一培养时未检测到的活性物质咖啡酸,其中接种量为7 g/L时的共培养Epa+Epu不定根中总咖啡酸衍生物产量最高,达136.22mg/L,是Epu单独培养时的1.35倍,Epa单独培养时的1.73倍。还原能力和DPPH自由基清除率也是接种量为7 g/L时的Epa+Epu不定根组合较高。此结果为大规模生产具有抗肿瘤抗氧化药用价值的紫锥菊医学药材提供技术参数。

To optimize the combination and inoculum density for co-culture system of Echinacea adventitious roots(ARs),three species:Echinacea purpurea(Epu),Echinacea pallida(Epa)and Echinacea angustifolia(Ean),the adventitious roots of which as experiment materials were inoculated into 500 mL flasks containing 200 mL of half strength Murashige and Skoog(MS)medium supplemented with 1 mg·L-1 of indole-3-butyric acid(IBA).The effects of species combinations and inoculum densities 5 g/L,7 g/L and 10 g/L were evaluated via the biomass of Echinacea ARs,content of secondary metabolites in the ARs and the antioxidant activity of the ARs extract.The results show that the maximum yield of ARs dry weight(6.75 g/L)was the combination of Epa+Epu with inoculum density of 7 g/L,in which both the content and productivity of total phenolics(40.31 mg/g DW and 272.09 mg/L)and flavonoids(34.29 mg/g DW and 231.46 mg/L)maximized.Only in ARs of Epa+Epu combination could all six caffeic acid derivatives be detected simultaneously among combinations.Furthermore,the caffeic acid,which could not be examined out in ARs of Epa or Epu in single culture was generated by the stimulation of co-culture system.The total content of caffeic acid derivatives in ARs of Epa+Epu combination achieved a maximum with 7 g/L inoculum density,productivity of which 136.22 mg/L was respectively 1.35 times and 1.73 times of that in Epu and Epu in single culture.The strongest reducing power and DPPH radical scavenging ability was also from the ARs extract of Epa+Epu combination with 7 g/L inoculum density.Such optimization of culture conditions will beneficial for the large-scale production of Echinacea biomass and bioactive compounds for antitumor and antioxidant biomedical materials.