The aim of this study was to determine intra- and interspecies variation in the qualitative and quantitative composition of methanol-soluble metabolites in the leaves of three
species (
,
, and
) ...from the central Balkans. Despite the steady use of foxglove constituents for human health as valuable medicinal products, populations of the genus
(
) have been poorly investigated to describe their genetic and phenetic variation. Following untargeted profiling using UHPLC-LTQ Orbitrap MS, by which we identified a total of 115 compounds, 16 compounds were quantified using the UHPLC(-)HESI-QqQ-MS/MS approach. In total, 55 steroid compounds, 15 phenylethanoid glycosides, 27 flavonoids, and 14 phenolic acid derivatives were identified across the samples with
and
showing a great similarity, while 15 compounds were characteristic only for
. The phytochemical composition of methanol extracts, considered here as complex phenotypes, are further examined along multiple levels of biological organization (intra- and interpopulation) and subsequently subjected to chemometric data analysis. The quantitative composition of the selected set of 16 chemomarkers belonging to the classes of cardenolides (3 compounds) and phenolics (13 compounds) pointed to considerable differences between the taxa studied.
and
were found to be richer in phenolics as compared to cardenolides, which otherwise predominate in
over other compounds. PCA revealed lanatoside C, deslanoside, hispidulin, and
-coumaric acid to be the main compounds contributing to the differences between
on one side and
and
on the other, while
-coumaric acid, hispidulin, and digoxin contribute to the diversification between
and
. However, quantitative variation in the metabolite content within species was faint with mild population diversification visible in
and particularly in
This pointed to the highly conserved content and ratio of targeted compounds within the analyzed species, which was not severely influenced by the geographic origin or environmental conditions. The presented metabolomics approach might have, along with morphometrics and molecular genetics studies, a high information value for further elucidation of the relationships among taxa within the genus
.
Herein, we present the effect of surface dielectric barrier discharge (SDBD) air cold plasma on regrowth of chrysanthemum synthetic seeds (synseeds) and subsequent plantlet development. The plasma ...system used in this study operates in air at the frequency of 50 Hz. The detailed electrical characterization of SDBD was shown, as well as air plasma emission spectra obtained by optical emission spectroscopy. The chrysanthemum synseeds (encapsulated shoot tips) were treated in air plasma for different treatment times (0, 5 or 10 min). Plasma treatment significantly improved the regrowth and whole plantlet development of chrysanthemum synseeds under aseptic (in vitro) and non-aseptic (ex vitro) conditions. We evaluated the effect of SDBD plasma on synseed germination of four chrysanthemum cultivars after direct sowing in soil. Germination of synseeds directly sowed in soil was cultivar-dependent and 1.6-3.7 fold higher after plasma treatment in comparison with untreated synseeds. The study showed a highly effective novel strategy for direct conversion of simple monolayer alginate chrysanthemum synseeds into entire plantlets by plasma pre-conversion treatment. This treatment reduced contamination and displayed a considerable ex vitro ability to convert clonally identical chrysanthemum plants.
Secoiridoid glucosides (SGs) are monoterpenoids derived from the iridoid cyclopentane-C-pyran skeleton with
β
-D glucose linked at C1 position. Coordinated metabolic processes, such as biosynthesis ...and catabolism of SGs, ensure constitutive presence of these bitter tasting compounds in plant tissues, which plays a decisive role in the defense against pathogens and herbivores. These compounds are susceptible to hydrolysis mediated by enzymes
β
-glucosidases, and the resulting aglycones are subsequently directed toward different metabolic pathways in plants. Function of two
β
-D-glucosidases (named
Ce
BGlu1 and
Ce
BGlu2) from centaury (
Centaurium erythraea
Rafn; fam. Gentianaceae), belonging to the glycoside hydrolase 1 (GH1) family, was confirmed using
in vitro
assays with recombinant proteins, following their heterologous expression in
E. coli
and His-tag affinity purification. Although they show slightly differential substrate preference, both isoforms display high specificity toward SGs and the organ-specific distribution of transcripts was positively correlated with the content of SGs in diploid and tetraploid
C. erythraea
plants. Transient overexpression of
Ce
BGlu1 and
Ce
BGlu2 in
C. erythraea
leaves induced changes in metabolite profiles. The effectiveness of transgene overexpression has been altered by plant ploidy. UHPLC/DAD/(±)HESI − MS
2
profiling of leaves of diploid and tetraploid
C. erythraea
genotypes revealed that the amounts of major SGs; sweroside, swertiamarin, and gentiopicrin was decreased in agroinfiltrated leaves, especially when
Ce
BGlu1 and
Ce
BGlu2 were co-expressed with transgene silencing suppressor p19. The work demonstrates that
in planta
metabolic engineering adopting transient overexpression of
Ce
BGlu1 and
Ce
BGlu2 is a suitable tool for the modulation of SGs content and glucosides/aglycones ratio, which might have substantial effects on overall phytochemistry of
C. erythraea
.
Prenylated flavonoids (PFs) are natural flavonoids with a prenylated side chain attached to the flavonoid skeleton. They have great potential for biological activities such as anti-diabetic, ...anti-cancer, antimicrobial, antioxidant, anti-inflammatory, enzyme inhibition, and anti-Alzheimer's effects. Medicinal chemists have recently paid increasing attention to PFs, which have become vital for developing new therapeutic agents. PFs have quickly developed through isolation and semi- or full synthesis, proving their high value in medicinal chemistry research. This review comprehensively summarizes the research progress of PFs, including natural PFs from the Moraceae family and their pharmacological activities. This information provides a basis for the selective design and optimization of multifunctional PF derivatives to treat multifactorial diseases.
The present study provides, for the first time, a physicochemical and biochemical characterization of the redox processes associated with the ripening of
L. (bittersweet) berries. Electron ...Paramagnetic Resonance Spectroscopy (EPRS) and Imaging (EPRI) measurements of reactive oxygen species (ROS) were performed in parallel with the tissue-specific metabolic profiling of major antioxidants and assessment of antioxidant enzymes activity. Fruit transition from the mature green (MG) to ripe red (RR) stage involved changes in the qualitative and quantitative content of antioxidants and the associated cellular oxidation and peroxidation processes. The skin of bittersweet berries, which was the major source of antioxidants, exhibited the highest antioxidant potential against DPPH radicals and nitroxyl spin probe 3CP. The efficient enzymatic antioxidant system played a critical protective role against the deleterious effects of progressive oxidative stress during ripening. Here, we present the EPRI methodology to assess the redox status of fruits and to discriminate between the redox states of different tissues. Interestingly, the intracellular reoxidation of cell-permeable nitroxide probe 3CP was observed for the first time in fruits or any other plant tissue, and its intensity is herein proposed as a reliable indicator of oxidative stress during ripening. The described noninvasive EPRI technique has the potential to have broader application in the study of redox processes associated with the development, senescence, and postharvest storage of fruits, as well as other circumstances in which oxidative stress is implicated.
The aim of this study was to comparatively analyze chemical composition and biological activity of wild- and in vitro grown Rindera umbellata. Explants were cultivated on 0.003–0.3 M sucrose, ...fructose, or glucose. HPLC-DAD for quantifying rosmarinic (RA) and lithospermic B (LAB) acids and GC-MS/FID for qualitative pyrrolizidine alkaloids (PAs) detection were used. Antioxidant activity (DPPH and ABTS assays) and cytotoxicity (MTT test) were monitored. Identified PAs were 7-angeloyl heliotridane, lindelofine, 7-angeloyl heliotridine, 7-angeloyl-9-(+)-trachelanthylheliotridine, punctanecine, and heliosupine, with higher variability reported in wild-growing samples. Total phenolic contents (TPCs) were comparable in wild-growing and in vitro samples, but total flavonoid (TFC) and RA levels were multifold higher in in vitro samples. Notably, high concentration of LAB was detected in wild-growing roots. Amounts of 0.3 M and 0.1 M of sucrose were optimal for TFC and RA production, while maximal antioxidant activity was monitored in plants grown on 0.3 M sucrose. The MTT test indicated colorectal HT-29 as more sensitive than A549 lung adenocarcinoma and normal MRC-5 cells, showing selective sensitivity to wild-growing and 0.3 M sucrose samples. In conclusion, PAs in vitro, as well as TPC, TFC, RA, and LAB in both growing conditions were detected for the first time in R. umbellata.
When exposed to stressful conditions, plants produce numerous volatile organic compounds (VOCs) that have different biological and environmental functions. VOCs emitted during the rehydration process ...by the fronds of desiccation tolerant fern Asplenium ceterach L. were investigated. Headspace GC–MS analysis revealed that the volatiles profile of rustyback fern is mainly composed of fatty acid derivatives: isomeric heptadienals (over 25%) and decadienals (over 20%), other linear aldehydes, alcohols, and related compounds. Aerial parts of the rustyback fern do not contain monoterpene-type, sesquiterpene-type, and diterpene-type hydrocarbons or corresponding terpenoids. Online detection of VOCs using proton-transfer reaction mass spectrometry (PTR–MS) showed a significant increase in emission intensity of dominant volatiles during the first hours of the rehydration process. Twelve hours after re-watering, emission of detected volatiles had returned to the basal levels that corresponded to hydrated plants. During the early phase of rehydration malondialdehyde (MDA) content in fronds, as an indicator of membrane damage, decreased rapidly which implies that lipoxygenase activity is not stimulated during the recovery process of rustyback fern.
Rafn produces and accumulates various biologically active specialized metabolites, including secoiridoid glucosides (SGs), which help plants to cope with unfavorable environmental conditions. ...Specialized metabolism is commonly modulated in a way to increase the level of protective metabolites, such as SGs. Here, we report the molecular background of the wounding-induced changes in SGs metabolism for the first time. The mechanical wounding of leaves leads to a coordinated up-regulation of SGs biosynthetic genes and corresponding JA-related transcription factors (TFs) after 24 h, which results in the increase of metabolic flux through the biosynthetic pathway and, finally, leads to the elevated accumulation of SGs 96 h upon injury. The most pronounced increase in relative expression was detected for secologanin synthase (
)
highlighting this enzyme as an important point for the regulation of biosynthetic flux through the SG pathway. A similar expression pattern was observed for
imposing itself as the TF that is prominently involved in wound-induced regulation of SGs biosynthesis genes. The high degree of positive correlations between and among the biosynthetic genes and targeted TFs expressions indicate the transcriptional regulation of SGs biosynthesis in response to wounding with a significant role of
, which is a known component of the jasmonic acid (JA) signaling pathway.
Phosphinothricin (PPT) is one of the most widely used herbicides. PTT targets glutamine synthetase (GS) activity in plants, and its phytotoxicity is ascribed to ammonium accumulation and reactive ...oxygen species bursts, which drives rapid lipid peroxidation of cell membranes. In agricultural fields, PPT is extensively sprayed on plant foliage; however, a portion of the herbicide reaches the soil. According to the present study, PPT absorbed via roots can be phytotoxic to Arabidopsis, inducing more adverse effects in roots than in shoots. Alterations in plant physiology caused by 10 days exposure to herbicide via roots are reflected through growth suppression, reduced chlorophyll content, perturbations in the sugar and organic acid metabolism, modifications in the activities and abundances of GS, catalase, peroxidase, and superoxide dismutase. Antagonistic interaction of
essential oil (
EO) and PPT, emphasizes the existence of complex control mechanisms at the transcriptional and posttranslational level, which result in the mitigation of PPT-induced ammonium toxicity and in providing more efficient antioxidant defense of plants. Simultaneous application of the two agents in the field cannot be recommended; however,
EO might be considered as the PPT post-treatment for reducing harmful effects of herbicide residues in the soil on non-target plants.
•Centauries are an appreciative source of biologically active compounds.•Phenolics, flavonoids, xanthones and secoiridoid glycosides were quantified.•Considerable antioxidant activities and ferric ...reducing capacity was recorded.•Appreciative antibacterial and strong antifungal activities were demonstrated.•Centauries could be recommended as food preservation additives.
Methanol extracts of aerial parts and roots of five centaury species (Centaurium erythraea, C. tenuiflorum, C. littorale ssp. uliginosum, C. pulchellum, and Schenkia spicata) were analysed for their main secondary metabolites: secoiridoid glycosides, a group of monoterpenoid compounds, and phenolics (xanthones and flavonoids), and further investigated for antioxidant capacity and antimicrobial activity. The results of ABTS, DPPH, and FRAP assays showed that above ground parts generally displayed up to 13times higher antioxidant activity compared to roots, which should be related to higher phenolics content, especially flavonoids, in green plant organs. Secoiridoid glycosides showed no antioxidant activity. All the tested extracts demonstrated appreciative antibacterial (0.05–0.5mgml−1) and strong antifungal activity (0.1–0.6mgml−1). Our results imply that above ground parts of all centaury species studied, could be recommended for human usage as a rich source of natural antioxidants and also in food industry as strong antimicrobial agents for food preservation.
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