Huang Wen-Jing, Sun Xiao-Chun, Li Bo, Shi Xin-Bo, Yue Zheng-Gang, Cai Xing-Hang, Yang Jie, Tang Zhi-Shu
Shaanxi Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Shaanxi University of Chinese Medicine, Xianyang 712083, China.
Zhongguo Zhong Yao Za Zhi. 2018 Oct;43(19):3855-3861. doi: 10.19540/j.cnki.cjcmm.20180528.007.
To explore the effects of shading and the expression of key enzyme genes on the synthesis and accumulation of Panax japonicus var. major saponins, different shading treatments (0%, 30%,50%) of potted P. japonicus var. major were used as test materials, the expression of three key enzyme genes(CAS,DS,-AS) of leaves and rhizomes in different growth periods of P. japonicus var. major was determined by real-time quantitative PCR, the content of total saponins was determined by ultraviolet spectrophotometry. The results indicated that, in flowering stage, CAS,DS,-AS were highly expressed in the aerial parts of P. japonicus var. major, 30% shading treatment significantly inhibited the expression of CAS in leaves and promoted the expression of DS and -AS in stems, leaves and flowers, it was speculated that the main part of saponin synthesis was leaf in this stage. Both the expression levels of DS and -AS and changes in the content of total saponins in leaves showed a tendency of low-high-low throughout the growth cycle, correlation coefficient analysis showed that there was a positive correlation between them. Compared with control, the expression levels of DS and -AS and the content of total saponins were greatly enhanced under shading treatment, 30% shading treatment significantly promoted the accumulation of total saponins. Therefore, it is suggested that 30% shading treatment should be applied to the artificial cultivation of P. japonicus var. major, which is beneficial to the accumulation and quality improvement of saponins.
为探究遮荫及关键酶基因表达对大叶三七皂苷合成与积累的影响，以盆栽大叶三七为试验材料，设置不同遮荫处理（0%、30%、50%），采用实时荧光定量PCR法测定大叶三七不同生育期叶片和根茎中3个关键酶基因（CAS、DS、-AS）的表达量，用紫外分光光度法测定总皂苷含量。结果表明，在花期，CAS、DS、-AS在大叶三七地上部分高表达，30%遮荫处理显著抑制叶片中CAS的表达，促进茎、叶、花中DS和-AS的表达，推测此阶段皂苷合成的主要部位是叶片。整个生长周期内，叶片中DS和-AS的表达量及总皂苷含量变化均呈低-高-低趋势，相关性系数分析表明二者呈正相关。与对照相比，遮荫处理下DS和-AS的表达量及总皂苷含量均大幅提高，30%遮荫处理显著促进总皂苷的积累。因此，建议在大叶三七人工栽培中采用30%遮荫处理，有利于皂苷的积累和品质提升。
