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Curcumin (Cur) is a natural anticancer pigment, but its poor absorption and extensive metabolism limit its clinical applications. In this study, an ultra‐high performance liquid chromatography/quadrupole time‐of‐flight mass spectrometry method was employed to investigate the metabolic profiles of a Cur self‐emulsifying drug delivery system (C‐SEDDS) in rat plasma, urine, bile and feces after oral administration at 100 mg/kg. Protein precipitation, solid‐phase and ultrasonic extractions were used to prepare different biosamples. A total of 34 metabolites were identified using available reference standards, or tentatively identified based on the mass spectrometric fragmentation patterns and the chromatographic elution order. Nine metabolites of Cur were found for the first time in vivo. Glucuronidation, sulfation, reduction, dehydroxylation, demethylation, demethoxylation and methylation were its possible metabolic reactions. Moreover, the differences were compared in terms of plasma metabolites found in C‐SEDDS‐treated, Cur suspension‐treated and rats treated with a commercial curcuminoid phospholipid complex administered at the same oral dose. Dihydrocurcumin (DHC), DHC glucuronide and methylated DHC were found only in the metabolic profile of C‐SEDDS‐treated rat plasma, suggesting that different drug delivery systems may cause a change in Cur metabolic pathways. This study provides a sensitive and rapid method for the identification of Cur metabolites in biosamples. [ABSTRACT FROM AUTHOR]

Tree peony ( Paeonia suffruticosa ) is a traditional Chinese flower that is not resistant to high temperatures, and the frequent sunburn during summer limits its normal growth. The lack of understanding of the molecular mechanisms in tree peony has greatly restricted the improvement of novel heat-tolerant varieties. Therefore, we treated tree peony cultivar "Yuhong" ( P. suffruticosa "Yuhong") at normal (25°C) and high temperatures (40°C) and sequenced the transcriptomes, to investigate the molecular responsive mechanisms to heat stress. By comparing the transcriptomes, a total of 7,673 differentially expressed genes (DEGs) were detected comprising 4,220 upregulated and 3,453 downregulated genes. Functional annotation showed that the DEGs were mainly related to the metabolic process, cells and binding, carbon metabolism, and endoplasmic reticulum protein processing. qRT-PCR revealed that three sHSP genes ( PsHSP17.8 , PsHSP21 , and PsHSP27.4 ) were upregulated in the response of tree peony to heat stress. Tissue quantification of the transgenic lines ( Arabidopsis thaliana ) showed that all three genes were most highly expressed in the leaves. The survival rates of transgenic lines ( PsHSP17.8 , PsHSP21 , and PsHSP27.4 ) restored to normal growth after high-temperature treatment were 43, 36, and 31%, respectively. In addition, the activity of superoxide dismutase, accumulation of free proline, and chlorophyll level was higher than those of the wild-type lines, while the malondialdehyde content and conductivity were lower, and the membrane lipid peroxidation reaction of the wild-type plant was more intense. Our research found several processes and pathways related to heat resistance in tree peony including metabolic process, single-organism process, phenylpropane biosynthesis pathway, and endoplasmic reticulum protein synthesis pathway. PsHSP17.8 , PsHSP21 , and PsHSP27.4 improved heat tolerance by increasing SOD activity and proline content. These findings can provide genetic resources for understanding the heat-resistance response of tree peony and benefit future germplasm innovation., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Ma, Wang, Wang, Shang, Zhao, Zhang, Ma, Hong and Gu.)