The intention of this study was to investigate the effect of steaming processing on phenolic profiles and antioxidant activities in chestnuts. Steaming processing at different times and temperatures depicted diverse impacts on free and bound fractions. Though, bound phenolics were stable but long time steaming at higher temperatures tended to improve the levels of phenolics, flavonoids as well as antioxidant activities in chestnut kernels, by up to 60.11% of the original value. Seven phenolic compounds including ferulic acid, chlorogenic acid, gallic acid, vanillic acid, syringate, p-coumaric acid and quercetin were found to change during thermal processes. Significant relationships (p < 0.05) were identified between total phenolics and total antioxidant activities. However, the consistency of chlorogenic acid (p < 0.01) only with cellular antioxidant activity indicated poor bio-accessibility of the phytochemicals in chestnuts. However, this situation could be partly improved by steaming. Steaming could improve the cellular accessibility of free phytochemicals, particularly, increasing the bio-accessibility by 41.96%. This study provided valuable information on dynamic changes of phenolic profiles and antioxidant activity of chestnuts under a steaming process, which could offer possible guidance for the chestnut processing industry in the future.

Carotenoids and folate are two mandatory supplying micronutrients for children or pregnant women. Inadequate intake of these two nutrients was relevant to a higher mortality of both children and pregnancies. This study is intended to investigate the thermal impact on the changes of carotenoids and folate in sweet potato roots (SPRs). Carotenoids were identified by high performance liquid chromatography (HPLC) while the folate was estimated using a microbial assay. An obvious decline was observed in total carotenoids after heating. Nevertheless, the content of provitamin compound β-carotene exhibited incredible stability during steaming and α-carotene multiplied in certain varieties, evidencing that SPRs could be an efficient way for addressing Vitamin A deficiency (VAD). As for the total folate contents, two varieties were found no significant loss after thermal process while the others showed a significant decrease. The results indicated that steaming process led to generally loss of both carotenoids and folate while the α-carotene and β-carotene were well preserved. The information provided by this study might help with enhancing the food quality in processing industry and the understanding in the nutrition changes during steaming.

The SQUAMOSA promoter binding protein-like (SPL)SPL family genes play an important role in regulating plant growth and development, synthesis of secondary metabolites, and resistance to stress. Understanding of the role of the SPL family in tobacco is still limited. In this study, 42 NtSPL genes were identified from the genome of the tobacco variety TN90. According to the results of the conserved motif and phylogenetic tree, the NtSPL genes were divided into eight subgroups, and the genes in the same subgroup showed similar gene structures and conserved domains. The cis-acting element analysis of the NtSPL promoters showed that the NtSPL genes were regulated by plant hormones and stresses. Twenty-eight of the 42 NtSPL genes can be targeted by miR156. Transcriptome data and qPCR results indicated that the expression pattern of miR156-targeted NtSPL genes was usually tissue specific. The expression level of miR156 in tobacco was induced by Cd stress, and the expression pattern of NtSPL4a showed a significant negative correlation with that of miR156. These results suggest that miR156-NtSPL4a may mediate the tobacco response to Cd stress. This study lays a foundation for further research on the function of the NtSPL gene and provides new insights into the involvement of NtSPL genes in the plant response to heavy metal stress.

Artemisinin is biosynthesized in Artemisia annua and widely used for the treatment of malaria. Abscisic acid (ABA)‐responsive kinase 1 (AaAPK1), a member of the SnRK2 family, is involved in the regulation of artemisinin biosynthesis through the phosphorylation of AabZIP1, which directly transactivates genes involved in artemisinin biosynthesis. Through diverse assays – including yeast two‐hybrid and bimolecular fluorescence complementation assays – we report that the ABA‐responsive protein phosphatase AaPP2C1 physically interacts with AaAPK1. In addition, phos‐tag mobility shift assays indicate that AaPP2C1 dephosphorylates AaAPK1. Moreover, dual‐luciferase assays demonstrate that the presence of AaPP2C1 reduces the transactivation of artemisinin biosynthesis genes by AabZIP1. These results further refine the post‐translational regulatory network of artemisinin biosynthesis, showing that AaPP2C1 is negatively involved through dephosphorylation of AaAPK1.