The gas chromatography-mass spectrometry was used to isolate and identify metabolites of non-transgenic and Bacillus thuringiensis transgenic maize. The non-targeted metabolomics technique was used to analysis the metabolic pathway and mechanism of two kinds of maize. The methanol was used as extractant and the N,O-bis(trimethylsilyl) trifluoroacetamide was used as derivatization reagent. 38 kinds of metabolites were isolated and identified from non-transgenic maize, and 61 kinds of metabolites were isolated and identified in Bacillus thuringiensis transgenic maize. The specific metabolites between non-transgenic and Bacillus thuringiensis transgenic maize were analyzed. The metabolic pathway of specific metabolites was analyzed by KEGG annotation. The metabolic mechanism of non-transgenic maize and Bacillus thuringiensis transgenic maize was explored. The result indicated there were more metabolites involved in metabolic pathways in Bacillus thuringiensis transgenic maize than in non-transgenic maize, and tricarboxylic acid cycle and energy metabolism pathways of Bacillus thuringiensis transgenic maize are found to be higher than that of non-transgenic maize. The metabolic pathway of Bacillus thuringiensis transgenic maize conforms to the biological activity law.
Tilia miquelianais an endemic species belonging to the genusTiliaL. (Tiliaceae) in China, which is known for its fragrant flowers and nectar, but the dynamic changes in metabolites during its growth and development are still unclear. In this study, the metabolic profiles fromT. miquelianaflowers at three developmental stages were detected by performing an ultra-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (UPLC-ESI-MS/MS)-based widely targeted metabolomic analysis. A total of 1138 metabolites were detected, with 288 Differentially Accumulated Metabolites (DAMs) determined, flavonoids accounting for the largest proportion. The trend analysis showed that DAMs present seven distinctive patterns, and subclass 5 obtained the largest amount with continuously increased relative content during flower development. The Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation and enrichment analysis of DAMs showed different overlap and variability in metabolic pathways, indicating different directions of flavonoids’ metabolic flux in the three developmental stages. A correlation network analysis further revealed five core metabolites that played essential roles in flavonoid biosynthesis. This research provides comprehensive insights into the exploitation and utilization ofT. miquelianaas well as a scientific basis for phylogenetic studies of the genusTilia.
危险品化学品经营许可证（带存储）