Na Wang,Jing Liu,Ling He,Tie Zhou,Bo Rong,Liang Wang,Xiang Zhao
An effective method for characterizing Chinese lacquer as binding medium in historical artwork has been developed by on-line methylation pyrolysis-gas chromatography–mass spectrometry (pyrolysis GC–MS). The characteristic pyrolytic components of Chinese lacquer were identified in artificially aged pure and pigmented lacquer. Methylation of urushiol (mainly composed of catechol derivatives) was performed by adding tetramethyl ammonium hydroxide to convert phenolic hydroxyl groups into methylated derivatives to improve the resolution of catechol derivatives and urushiol monomers. The mechanism of formation of small molecular components was proposed, and the influence of different mineral pigments (azurite, malachite, ochre, and cinnabar) on the determination of characteristic components was discussed. Aliphatic hydrocarbon components, benzene derivatives, catechol derivatives, and urushiol monomers were proposed as characteristic pyrolytic components. In addition to 3-pentadecene-catechol, 3-pentadecane-catechol, and 3-heptadecene-catechol, 3-pentadecene-phenol was also identified as an urushiol monomer in Chinese lacquer. Four pigments slightly reduced the detection of aliphatic hydrocarbon components, but were unconspicuous for the detection of benzene derivatives. Azurite, malachite, and cinnabar decreased the measurement of urushiol monomers, but ochre significantly increased their relative abundance. The established on-line methylation pyrolysis GC–MS procedure and summarized data were successfully applied to the identification of samples collected from Terra-Cotta Warriors and Horses of Qin Dynasty (221–207 BC), Han Yang Mausoleum of Han Dynasty (206 BC–24 AD), and Dazu Grotto of Tang Dynasty (618–907 AD).
Background and AimsChinese pistachio (Pistacia chinensis Bunge), an important horticultural plant species, holds great ornamental value with beautiful leaves and fruits. Seedling propagation of this tree species is restricted by its erratic seed germination, however, the germination mechanism is ambiguous yet. The aim of this study was to figure out the germination mechanism from the novel perspective based on the multi-omics data.MethodsThe multi-omics technique combined with hormone content measurement was first applied in seed germination of Chinese pistachio.Key ResultsDue to the great accumulation during seed germination, catechin stood out from the identified metabolites by broadly targeted metabolomic analysis. Exogenous catechin of 10 mg/L significantly improved the germination of Chinese pistachio seeds. An interesting result of hormone analysis showed that the improving effect of catechin could be attributed to increase of the gibberellic acid 3 (GA3) content rather than decrease of the abscisic acid (ABA) content before germination. The paclobutrazol (PAC, a GA biosynthesis inhibitor) and PAC + catechin treatments also showed that the promoting effect of catechin on seed germination depends on GA biosynthesis. Transcriptome analysis and qRT‒PCR further revealed that catechin induced the expression of PcGA20ox5 to activate GA biosynthesis. Several transcription factors were induced by catechin and GA treatments, such as TCP, bZIP and C3H, which may play an important regulatory role in GA biosynthesis in a catechin-mediated way.ConclusionsCatechin promotes seed germination via GA biosynthesis in Chinese pistachios. This study proposes a novel mechanism by which catechin promotes seed germination via the GA pathway, which provides new insight into a comprehensive understanding of seed dormancy and germination.
危险品化学品经营许可证（带存储）