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研究了红参皂甙(总皂甙 ,皂甙组分Rb1 和Rg1)对酵母菌(Saccharomycescerevisiae)中的 β-半乳糖甙酶诱导的影响 ,认为人参皂甙将穿过细胞膜 ,在细胞核中起甾体激素作用。为了达到这一目的 ,把包含GAL1启动子的EcoRⅠ的DNA片段(685bp)插入到质粒YEp356(7.966kb)的LacZ基因上游的多酶切点 ,假设由此产生的质粒 pGAL1 -LacZ在半乳糖存在下仅表达 β-半乳糖甙酶。将质粒 pGAL1 -LacZ导入酵母菌KY106(a1eu2ura3his3trpl1ys2)中 ,转化细胞在半乳糖存在下 ,比在葡萄糖存在下生长得缓慢。检测了皂甙对转化酵母细胞中β-半乳糖甙酶特殊活性的影响。在这种条件下 ,总皂甙对酶活性没有明显的影响 ,而皂甙组分Rb1、Rg1 对酶活性却有明显地促进作用。最大提高幅度以10 %～3 %浓度的Rb1 为35 %,10 %～1 %的浓度的Rg1 为75 %。这些数据说明人参皂甙可能会进入到细胞核并刺激转录。但是 ,要确定这种可能性需要在找出假定皂甙受体的进一步研究
The effects of red ginseng saponins (total saponins, saponin components Rb1 and Rg1) on β-galactosidase induced by Saccharomyces cerevisiae were studied, and it was thought that ginsenosides will cross the cell membrane and act as steroid hormones in the nucleus. . For this purpose, the EcoRI DNA fragment containing the GAL1 promoter (685 bp) was inserted into the polyclotting site upstream of the LacZ gene of the plasmid YEp356 (7.966 kb), assuming that the resulting plasmid pGAL1 -LacZ exists in galactose. Only β-galactosidase was expressed. The plasmid pGAL1-LacZ was introduced into the yeast KY106 (a1eu2ura3his3trpl1ys2), and the transformed cells grew slowly in the presence of galactose rather than glucose. The effect of saponin on the specific activity of β-galactosidase in transformed yeast cells was examined. Under these conditions, total saponin had no significant effect on the enzyme activity, while saponin components Rb1 and Rg1 significantly promoted the enzyme activity. The maximum increase rate was 35% for Rb1 at 10% to 3% concentration, and 75% for Rg1 at 10% to 1% concentration. These data suggest that ginsenosides may enter the nucleus and stimulate transcription. However, to determine this possibility requires further research on the identification of putative saponin receptors.