外源H2O2对黄芩次生代谢调控及道地质量形成机制研究

Exogenous H2O2 regulated secondary metabolism of Scutellaria baicalensis and enhanced drug quality

中药材需求量的增加,野生药材已不能满足临床需要,栽培药材成为商品的主要来源。由于生长环境的改变,导致很多药材质量下降。提高药材质量已成为中药资源研究的重点和难点。采用H2O2喷施黄芩地上部分,超氧化物歧化酶（SOD）、过氧化氢酶（CAT）变化不明显,过氧化物酶（POD）和抗坏血酸氧化酶（APX）活性显著下降,表明黄芩抗氧化酶系统消除活性氧能力降低。同时,H2O2促进苯丙氨酸解氨酶（PAL）和β-葡萄糖苷酸酶（GUS）基因表达,提高了PAL活性,促进了黄酮类成分的生物合成和苷元类成分的转化。0.004μmol·L^-1H2O2处理后第2天,虽然黄芩苷和汉黄芩苷等苷类物质略有下降,但活性最高的成分苷元类成分显著升高,黄芩素由0.094%升高到0.324%,汉黄芩素由0.060%升高到0.110%,分别比对照提高了246%,83.3%。

The increasing demand of Chinese materia medica could not be supplied by wild resource,and the cultivated medicinal materials become popular,which led to decreased quality of many medicinal materials due to the difference of the circumstance between the wild and the cultivated. How to improve quality becomes key points of Chinese medicine resource. The leaves of Scutellaria baicalensis were sprayed with H2O2,the activities of superoxide dismutase（SOD） and catalase（CAT） changed little,but there had been a marked decrease of peroxidase（ POD） and ascorbic oxidase（ APX）,which showed that the antioxidase system declined. Meanwhile,H2O2,as enhanced the expression of phenylalnine ammonialyase（PAL） and β-glucuronidase（GUS） as well as activity of PAL,promoted the biosynthesis and biotransformation of flavonoids. At the day 2 after treated,H2O2 of 0. 004 μmol·L^-1 the contents of the baicalin and the wogonoside decreased slightly,but the contents of the baicalein and the wogonin increased significantly,the baicalein from 0. 094 % to 0. 324 %,the wogonin from 0. 060 % to 0. 110 %,i. e. increased 246 % and 83. 3 %,respectively.