抑制齐墩果烷型人参皂苷合成支路对达玛烷型人参皂苷生产能力的影响

表达反义βAS的5个人参发根系在液体培养条件下生长30天后,齐墩果烷型人参皂苷R0含量比对照实验组均有所降低,幅度分别达13%～40%;达玛烷型人参皂苷Rb1、Rb2、Rc、Rd、Re、Rf和Rg1含量在5个发根系中均有所增加,其中发根系A19的上述单体皂苷含量总和比对照实验组提高了30%;培养过程中达玛烷型人参皂苷含量呈逐渐增加趋势。5个发根系的βAS酶活性比对照实验组均有所下降,最多下降30%,DAS酶活性被上调,尤其发根系A19的酶活性比对照实验组提高了20%;化学分析结果显示,5个发根系人参皂苷前体物2,3-氧化角鲨烯的含量比对照实验组均有所提高。

Effects of suppressing oleanane-type ginsenoside biosynthesis on dammarane-type ginsenoside production

Five Panax ginseng hairy root lines expressing antisense βAS were established.After 30 days of growth cultured in liquid,the levels of oleanane-type ginsenoside Ro in these antisense hairy root lines decreased by 13% to 40% compared with control line.While levels of dammarane-type ginsenosides(Rb1,Rb2,Rc,Rd,Re,Rf and Rg1) increased in all five antisense hairy root lines,of which line A19 exhibited the max levels of dammarane-type ginsenosides,30% higher than those of control line.It was observed that dammarane-type ginsenosides contents in these hairy root lines gradually increased during culture process.Additionally,relative to control lines,βAS enzyme activities of the antisense lines decreased up to 30%;while DAS enzyme activities were enhanced,especially in the antisense lines A19(20% increase).Furthermore,the antisense lines show higher level of ginsenoside precursor(2,3-oxidosqualene) than the control line.