Selenium Regulates Antioxidant Capacities and Diterpenoid Biosynthesis in the Medicinal Plant Isodon rubescens  

作　　者：Fenglan Zhao Shuwen Wu Xue Meng Jianping Xue Yongbo Duan 

机构地区：[1]Anhui Provincial Engineering Laboratory for Efficient Utilization of Featured Resource Plants,College of Life Sciences,Huaibei Normal University,Huaibei,235000,China [2]Huaibei Key Laboratory of Efficient Cultivation and Utilization of Resource Plants,College of Life Sciences,Huaibei Normal University,Huaibei,235000,China

出　　处：《Phyton-International Journal of Experimental Botany》2024年第7期1705-1716,共12页国际实验植物学杂志（英文）

基　　金：supported by the Key Project of Natural Science Research for Colleges and Universities in Anhui Province(2023AH050345,KJ2021A0533);the Excellent Scientific Research and Innovation Team of Universities in Anhui Province(2022AH010029).

摘　　要：Dōng líng căo,the dried aboveground parts of Isodon rubescens(Hemls.)Hara.,is commonly consumed as a med-icinal decoction or tea beverage.Natural beverages can be an important source of human dietary selenium(Se).However,how I.rubescens plants respond to exogenous Se remains unknown.In this study,a pot cultivation experiment was employed to investigate the phenotypic and physiological responses of I.rubescens plants exposed to Se.Fifteen days after applying different concentrations of sodium selenate to the soil,the Se enrichment capa-city,growth indices,antioxidant capacities,and the content offlavonoids and diterpenoids were measured in the plants.Further,the oridonin content was quantified using the high-performance liquid chromatography method,and the expression levels of key diterpenoid synthesis genes were analyzed by quantitative real-time PCR(qRT-PCR).I.rubescens plants efficiently accumulated Se,with the Se content increasing proportionally to the applied dose,reaching levels of nearly 200 mg·kg^(-1) dry leaves as Se concentration increased.None of the three Se treat-ments significantly altered the phenotypic indices,except a longer root length occurred in the 3μM·kg^(-1) Se group.Among three Se doses,6μM·kg^(-1) Se gave the highest accumulation offlavonoids,diterpenoids,and oridonin,with the increase of 2.0-,1.8-,and 1.9-fold in aboveground parts,respectively.Selenium application boosted the activities of antioxidant enzymes and antioxidant capacities according to 2,2-Diphenyl-1-picrylhydrazyl(DPPH),ferric reducing/antioxidant power,and tea brewing color experiments.Four key synthase genes were upregulated significantly by 6μM·kg^(-1) Se treatment,notably 1-deoxy-D-xylulose 5-phosphate reductoisomerase(IrDXR),with a 5-fold increase,and kaurene synthase-like 4(IrKSL4),with a 6-fold increase.Thus,Se application in I.rubescens cultivation may be a potential biofortification method to supplement Se while increasingflavonoid and diterpenoid contents.

关 键 词：FLAVONOIDS ORIDONIN physiological indicators quantitative real-time PCR SELENIUM 

分 类 号：Q94[生物学—植物学]