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Augmented knowledge of plant responses upon application of stress could help improve our understanding of plant tolerance under abiotic stress conditions. Histone acetylation plays an important role in gene expression regulation during plant growth and development and in the response of plants to abiotic stress. The current study examines the level of transcripts and free metabolite content in transgenic Arabidopsis thaliana plants expressing a gene encoding histone acetyltransferase from Medicago truncatula ( MtHAC1 ) after its heterologous expression. Stable transgenic plants with HAC1 gain and loss of function were constructed, and their T 5 generation was used. Transgenic lines with HAC1 -modified expression showed a deviation in root growth dynamics and leaf area compared to the wild-type control. Transcriptional profiles were evaluated after the application of salinity stress caused by 150 mM NaCl at four different time points (0, 24, 48, and 72 h) in treated and non-treated transgenic and control plants. The content and quantity of free metabolites-amino acids, mono- and dicarbohydrates, organic acids, and fatty acids-were assessed at time points 0 h and 72 h in treated and non-treated transgenic and control plants. The obtained transcript profiles of HAC1 in transgenic plants with modified expression and control were assessed after application of cold stress (low temperature, 4 °C).

Sambucus ebulus (SE) fruits are used for immune stimulation and amelioration of gastrointestinal inflammatory conditions. Currently, there is no scientific evidence of their effects on various aspects of the immune response mechanisms in humans. The purpose of this study was to evaluate the immunomodulatory potential of SE fruit infusion intake in healthy humans. Anthocyanin content was determined with UPLC-ESI-MS/MS. Fifty-three volunteers enrolled in a 4-week SE infusion intake intervention. Blood count, serum total protein, Interleukin 1 beta (IL-1β), Interleukin 6 (IL-6), Tumor Necrosis Factor Alpha (TNFα), High-sensitivity C-reactive protein (hs-CRP), C3, and C4 levels were measured on automatic analyzers, and Interleukin 8 (IL-8) was measured manually with an ELISA kit. Cyanidin-3-O-galactoside (48.15 mg/g DW), followed by cyaniding-3-sambubioside (43.41 ± 1.07 mg/g DW), were the most abundant anthocyanins in SE samples. A significant decrease in total protein (2.82%), IL-6 (20.15%), TNFα (5.38%), IL-8 (5.50%), C3 (4.16%), and C4 (14.29%) was established in the whole group. Total protein, IL-8, TNFα, and C4 decreased in women (3.11%, 4.76%, 5.09%, and 11.11%), and IL-6 decreased (40.61%) in men. Hb (1.20%) and hematocrit (1.55%) levels decreased in the whole group and in the women group (1.61% and 2.20%). SE fruits exert immune-modulatory activity as revealed by decreased pro-inflammatory status and complement activity markers in healthy volunteers after a 4-week intervention.

Essential oils and hydrosols of two cultivars of muscadine grapes ( Muscadinia rotundifolia (Michx.) Small.) were obtained by hydro-distillation of flowers and berry skins. Twenty-three volatile compounds were identified in essential oils from the muscadine flowers, and twenty volatiles in their corresponding hydrosols. The composition of volatiles in berry skins differed significantly from that of the vine flowers. The antioxidant potential of investigated essential oils and hydrosols was evaluated using five in vitro assays: DPPH (2,2-diphenyl-1-picrylhydrazyl) method, TEAC (Trolox equivalent antioxidant capacity), FRAP (Ferric reducing antioxidant power), CUPRAC (cupric ion reducing antioxidant capacity), and NO (nitric oxide radical scavenging assay). The essential oils from the flowers of both cultivars showed the strongest antioxidant power, whereas the hydrosols were the significantly less active. All investigated essential oils showed very weak antibacterial activities against Bacillus cereus , Staphylococcus aureus , Escherichia coli , and Pseudomonas aeruginosa . However, the essential oils from the flowers of both cultivars showed moderate antifungal activities against Candida albicans , which were stronger for the oil from "Carlos" (white muscadine cultivar). To the best of our knowledge, this is the first report on obtaining and characterizing essential oils and hydrosols from muscadine grapes. This study demonstrated the variations in aromatic compounds accumulated in flowers and mature berry skins of muscadine grapes, and evaluated their possible antioxidant and antimicrobial activities. The presented results will be the base for future research, focused on a better understanding of the molecular and regulatory mechanisms involved in aromatic compound biosynthesis and accumulation in muscadine grapes.