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Five traditional medicinal food from the Tibetan plateau including Nitraria tangutorum Bobrov (NT), Hippophae rhamnoides L. (HR), Lycium ruthenicum Murray (LR), Lycium barbarum L. (LB) and Rubus corchorifolius L.f. (RC) are rich in phenolic compounds. However, the detailed studies about the phenolic compounds remain scarce. Therefore, we established a rapid method for the simultaneous identification and quantification of the phenolic compounds from berries via Ultra Performance Liquid Chromatography-Quadruple-Orbitrap MS system (UPLC-Q-Orbitrap MS). This method was verified from many aspects including detection limit, quantification limit, precision, repeatability, stability, average recovery rate and recovery range, and then was used to analyze the phenolic compounds in these five species of berries. Finally, a total of 21 phenolic compounds were directly identified by comparing the retention time and exact mass, of which 14 compounds were identified by us for the first time in berries from the Tibetan plateau, including one flavonoid aglycone (myricetin), 11 phenolic acids (gallic acid, protocatechuate, chlorogenic acid, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, ferulic acid, 2-hydroxybenzeneacetic acid and ellagic acid), one flavanol (catechin) and one dihydrochalcone flavonoid (phloretin). Quantitative results showed that rutin, myricetin, quercetin and kaempferol were the main flavonoids. Moreover, a variety of phenolic acid compounds were also detected in most of the berries from the Tibetan plateau. Among these compounds, the contents of protocatechuate and chlorogenic acid were high, and high levels of catechin and phloretin were also detected in these plateau berries.

The drought and salinity tolerances of a creeping ground-cover chrysanthemum variety ‘Yuhuaxunzhang’ were compared to the performance of its two derived transgenic lines carrying a drought-responsive element binding (DREB) factor from chrysanthemum designated as CgDREBa. The over-expression of CgDREBa conferred a measure of tolerance to both stresses. The transgenic lines showed a higher survival rate and were better able to retain fresh weight in the presence of stress. Activities of superoxide dismutase and peroxidase and the proline content were all higher in the leaves of the transgenic plants after a prolonged period of stress, but they accumulated less malondialdehyde. CgDREBa appears to function as a transcription activator of genes within the oxidative and osmotic homeostasis transduction pathways, and represents a promising candidate for a biotechnological approach to improve the level of abiotic stress tolerance in plants.