微波调控苦荞麦萌发富集黄酮类物质及关键酶基因表达机理研究

Microwave treatment can stimulate the germination of Tartary Buckwheat, improve the activity of enzymes and enhance the expression of translation. In the process of germination, the accumulation of the secondary metabolite flavonoids was promoted. But the mechanism of above phenomenon was not clear. To solve the problem, the effects of microwave treatment on the germinating of Tartary Buckwheat seed were investigated from the physiological and biochemical indexes, the species and content and distribution changes of flavonoids in germination. Furthermore, effect of microwave treatment on activity and content of three key enzymes of flavonoids synthesis including Phenylalanine ammonia lyase (PAL) and Chalcone isomerase (CHI) and Flavonol synthase (FLS) during the germination was studied. The influences of microwave treatment on the index and the status of the germination were analyzed. The relationship between the dynamic changes of flavonoids content and the microwave field was detected. The relationships between the dynamic changes of flavonoids content and the activity of PAL and CHI and FLS, and gene expression differences of the above three key enzymes were identified. The regulation mechanism of microwave treatment on the enrichment of flavonoids during Tartary buckwheat seeding at the molecular level would be revealed.

微波处理可刺激苦荞麦种子的萌发，提高种子中各种酶的活性和增强其表达，从而促进了萌发过程中次生代谢产物之一—黄酮类化合物的富集，但其机理尚不清楚。针对这一科学问题，本项目研究微波预处理下苦荞麦的萌发和主要生理生化指标的变化，萌发过程中黄酮类物质的种类、含量和分布的变化，进一步研究微波处理对苦荞麦种子中黄酮类化合物合成的3个关键限速酶—苯丙氨酸解氨酶(PAL)、查尔酮异构酶（CHI）和黄酮醇合成酶（FLS）活性及含量的影响。分析微波预处理对苦荞麦萌发指数、生长状况的影响，检测萌芽苦荞内黄酮类物质含量的动态变化与微波场条件的关系，明确黄酮类物质合成量的动态变化与其合成关键酶PAL、CHI和FLS的活性、基因表达差异性之间的关系，从而在分子水平上揭示微波预处理调控萌芽苦荞富集黄酮类化合物的机理。

研究了微波对苦荞种子萌发、营养和活性物质含量及抗氧化能力的作用。微波促进种子萌发，提升苦荞芽营养价值。微波能提高芽苗中总酚、总黄酮、芦丁等含量及对DPPH、ABTS、O2-和•OH的清除能力，且两者之间正相关。微波亦能提高芽苗SOD、CAT、POD和APX的活性。.研究了微波处理后苦荞芽中PAL、CHI和FLS的比活力变化规律与总黄酮含量的相关性。不同微波条件对同种酶的刺激效应，同一微波条件对3种酶的刺激效应均不同。微波刺激下PAL、CHI和FLS的比活力与黄酮的积累量均存在相关性。.研究了微波处理的苦荞芽中黄酮化合物的积累量与FtPAL、FtCHI、FtFLS1和FtFLS2转录水平的动态变化关系。微波提高芽苗中芦丁、绿原酸、牡荆素、二氢杨梅素、杨梅素和槲皮素含量。微波功率和时间对黄酮合成关键基因（FtPAL、FtCHI、FtFLS1和FtFLS2）的转录水平有不同程度的调节作用， FtPAL、FtCHI、FtFLS2转录水平的上调与黄酮类化合物的形成具有密切关系。.研究了微波处理对萌发苦荞蛋白质组的影响。微波改变了苦荞芽中蛋白质组的表达差异，生物信息学分析表明差异表达蛋白（DEPs）主要与能量合成和转换、基因表达以及黄酮类物质生物合成有关，并通过调节photosynthesis、RNA polymerase、flavonoid biosynthesis、phenylalanine metabolism和phenylpropanoid biosynthesis代谢途径，促进了苦荞萌发和黄酮类物质的积累。.综上，本项目揭示了微波处理调控苦荞蛋白质的差异表达，黄酮合成关键酶PAL、CHI和FLS的活性及其相关基因（FtPAL、FtCHI、FtFLS1和FtFLS2）的转录水平而促进黄酮类化合物积累、营养成分增加，为富含黄酮类化合物的苦荞芽菜生产及其产业化奠定了理论基础。