Change Of Secondary Metabolites And Differential Proteomics In Leaves Of Ginkgo Biloba L. Based On UV-B Induction Method

UV-B radiation could significantly enhance the contents of anti-toxins (flavonoids, lignans, etc.) in plants, also help the biosynthesis of new bioactive compounds. There were many applications of UV-B radiation in researching the antitoxin of crops, however, few had been reported on the subject of UV-B radiation improving the activity of Chinese medicine ingredients. In order to provide new technical methods of using medicinal resources rationally and improving the quality of medicine, this research revealed the molecular mechanism of UV-B radiation in influencing biosynthesis of the active ingredients at protein level.By using the technology of HPLC-DAD and 2D-Electrophoresis, our study successfully screened out the suitable condition for the UV-B radiation of Ginkgo leaf, isolated and identified the inducing compounds, and analyzed the differences proteome after radiation. Specific contents include as follows:1. In this study, freshly collected leaves were exposed to three UV-B radiation times: 120 min,240 min and 360 min. We studied qualitative and quantitative changes using high performance liquid chromatography (HPLC)-diode array detection (DAD) procedure. The results clearly revealed that the leaves response to UV-B radiation is radiation time-, plant leaf age-, phytochemical-specific and that these factors influence a change of secondary metabolism as revealed by the different total flavonoids concentration levels.2. In UV-B treated leaves of September, we obtained a significantly modified compound GB1, its structure was identified by 13C,1H NMR and ESI-MS, named3-(4'-hydroxyphenyl)-1-thiol-2-propylene.3. The proteomes of Ginkgo leaves before and after induction were analyzed by 2D-Electrophoresis method,66 different points were obtained through the processing of Progenesis SameSpots, and eventually 36 differential proteins were identified by MALDI-TOF-MS.The results showed that UV-B radiation could be used as novel techonology to enhance the acitive compounds in Ginkgo leaves. This technology not only provided a useful complement and drew to herbal biotechnology methods for improve the quality of Chinese products, but also for the sustainable development of Chinese medicine a valuable exploration.