Six Centaurea cyanus L. flower extract variants were prepared using methanol, ethanol or water as a solvent; in each case, the material was either defatted with chloroform or not. The phytochemical profile of all obtained extracts was analyzed qualitatively and quantitatively using UPLC-PDA-Q/TOF-MS. In total, 35 phenolic compounds were detected, including flavonols, flavones, anthocyanins, phenolic acids and their derivatives, as well as an N-p-coumaroyl spermidine derivative; some compounds were identified using authentic standards, while others were tentatively identified based on chromatography and mass spectrometry data. The defatted ethanolic extract showed the highest total quantified phenolic content (42.18 mg/g DW), with the predominant constituents being apigenin derivatives, particularly apigenin-O-hexoside-O-glucuronide and apigenin-3-O-glucoside-(6″-acetyl)glucoside. The extract exhibited notably high antioxidant capacity, viz. DPPH (240.34 µmol TE/g), ABTS (170.53 µmol TE/g), and FRAP (189.93 µmol TE/g), and moderate antimicrobial activity, particularly against E. coli (MIC 0.5 mg/mL). The extract did not exhibit any cytotoxic effect toward L929 or Hs68 fibroblasts in vitro at concentrations up to 5 mg/mL. These findings indicate that the phenolic-rich ethanolic extract demonstrated both antioxidant and antimicrobial activities while also being non-cytotoxic against fibroblasts within the tested concentration range; as such, it may be suitable for dermatological and cosmetic formulations.

The bright blue colouration of Centaurea cyanus (cornflower) is attributed to a supramolecular pigment formed via metal ion chelation with accumulated cyanidin (Cy) and co-pigments, yet the underlying genetic regulatory mechanisms remain incompletely understood. Elucidating this mechanism will facilitate the molecular breeding of cyanidin-based blue flowers, thereby enhancing the ornamental value of flowering plants. Initially, in vitro blue pigment reconstruction experiments identified that Fe[3+] is the primary metal ion enabling the blue transformation of Cy, and the molar ratio of Cy to Fe[3+] was found to be critical. Genomic analysis identified 11 VIT/VTL genes and four CcFers genes in cornflower. Expression profiling revealed an inverse expression relationship between CcVIT1a and CcFers across various tissues. Notably, CcVIT1a specifically and highly expressed in blue-coloured ray florets. Subcellular localization and yeast mutant complementation assay showed CcVIT1a in tonoplast, whereas the CcFers reside in plastids. This spatial separation suggests their coordinated role in regulating intracellular iron homeostasis. Virus-induced gene silencing of CcVIT1a caused a colour shift from blue to violet, indicating its critical role in blue colouration of cornflower. Concurrently, the expression of the CcFer1a was significantly upregulated, while the other three CcFers were downregulated, further supporting the idea that CcVIT1a and the CcFers collaboratively regulate intracellular iron homeostasis. Transient overexpression of CcVIT1a in chrysanthemum CB (Cy-determined blue flowers) sample 'Dante purple' induced a colour transition from red-purple to violet, accompanied by the downregulation of both CmVIT and CmFer1. These findings imply a similar synergistic mechanism governing iron homeostasis in chrysanthemum. This study elucidates the cooperative roles of VIT1 and Fer in regulating intracellular iron partitioning. We demonstrate that upregulation of CcVIT1a enhances iron sequestration into the vacuole, thereby promoting the cyanidin-based blue colouration. Collectively, our findings provide novel molecular insights and a potential strategy for breeding blue flowers through the manipulation of cyanidin and iron metabolism.

Edible flowers are emerging functional ingredients and dietary sources of anthocyanins, yet the influence of food matrices and digestion on their bioaccessibility and absorption remains unclear. Wild pansy (Viola tricolor), cosmos (Cosmos bipinnatus), and cornflower (Centaurea cyanus) were evaluated for nutritional composition, phytochemical content, and anthocyanin stability, digestibility, and absorption. All species showed high dietary fiber content, with species-dependent differences in nutritional and phenolic composition. Anthocyanin stability was pH- and matrix-dependent, and strongly influenced by anthocyanin structure. Digestion caused a marked reduction in anthocyanin recovery, particularly after the intestinal phase (up to 62.69% relative to the oral phase). Transepithelial transport assays showed reduced absorption efficiencies for digested extracts compared with free extracts (up to 67.53%), while food matrix components differentially modulated transport depending on matrix type and flower species. Overall, food matrices influenced anthocyanin stability and absorption, highlighting the relevance of matrix-anthocyanin-digestion interactions for dietary recommendations and functional food formulation.

Cornflower (Centaurea cyanus L.) is a widespread weed in cereal crops and is commonly controlled with sulfonylurea herbicides. In Poland, populations of cornflower resistant to acetolactate synthase inhibiting herbicides, such as tribenuron-methyl, have been increasingly reported. Both target-site and non-target-site resistance mechanisms may contribute to this phenomenon. Plant-associated microorganisms are known to play essential roles in alleviating abiotic stress. Moreover, weeds are considered reservoirs of plant pathogenic viruses. Since bacteria and viruses associated with cornflower have not been analysed to date, data mining was undertaken to identify viral and bacterial sequences in metatranscriptome datasets obtained from plant biotypes that are both susceptible and highly resistant to tribenuron-methyl. Using MEGAN6 and Kraken2, taxonomic classification revealed the presence of sequences of two double-stranded RNA viruses belonging to the family Partitiviridae, which have not been described before. For bacterial sequences, 19 genera were identified, including Bacillus, Mesorhizobium and Acinetobacter, some of which are associated with plant growth promotion or xenobiotic degradation. Although the presence of partitiviruses was unrelated to herbicide resistance status, some bacterial genera (e.g., Rothia) were more abundant in resistant than in susceptible plants. These results suggest that those bacterial genera present in weeds may be involved in counteracting ALS-inhibiting herbicides.

Centratherum punctatum (Asteraceae), known as Brazilian bachelor's button, is used in folk medicine to treat liver problems, intestinal discomfort, and ulcers. The study aims to characterize the ethanolic extract (EE) of C. punctatum leaves, evaluate its antioxidant activity, and assess its cytogenotoxic and chemoprotective effects in Allium cepa and Drosophila melanogaster cells. The EE was characterized by qualitative phytochemical prospecting, TLC, ESI-IT/MS[n], HPLC-PDA, and isolation by column chromatography. Antioxidant activity (DPPH and ABTS) and total phenol content (TPC) were quantified. Cytogenotoxicity and the protective effect of EE were evaluated in the A. cepa and the somatic mutation and recombination test (SMART) bioassays at concentrations of 3.9; 15.6; 62.5 and 250 µg/mL. The phytochemical prospecting of EE revealed the presence of tannins, saponins, flavanones, alkaloids, terpenes, and flavonoids. ESI-IT/MS[n] identified 15 compounds, HPLC-PDA also confirmed the same classes of metabolites, and the isolate was the triterpene acetyl aleuritolic acid. The result of DPPH, ABTS, and TPC was 142.10 ± 2.15 µg/mL; 623.94 ± 38.38 mM Trolox/g, and 77.78 ± 1.19 mg EAG/g, respectively. In A. cepa and SMART, none of the EE concentrations were cytogenotoxic. EE showed a protective effect (pre, simultaneous, and post-treatments) against methyl methanesulfonate damage at all concentrations in A. cepa and antigenotoxic activity (simultaneous) in SMART at 15.6; 62.5, and 250 µg/mL against doxorubicin damage. The findings of the present study demonstrate that C. punctatum is a promising source of compounds with antioxidant and chemoprotective properties.

Exposure to electromagnetic radiation (EMR) at varied power densities can profoundly affect fertilization in plants by posing physiological stress and impairing pollen's ability to fertilize. In the present study, four sites (under exposure to EMR at varied power densities) like S-1 (1 μW/cm2), S-2 (2.8 μW/cm2), S-3 (5.5 μW/cm2), and S-4 (15 μW/cm2) were selected for collection of pollen grain samples of 12 plant species naming Alcea rosea L., Centaurea cyanus L., Chrysanthemum coronarium L., Dahlia pinnata Cav., Gaillardia pulchella Foug., Jatropha integerrima Jacq., Papaver somniferum L., Rosa indica L., Tagetes erecta L., Tropaeolum majus L., Verbena pulchella Greene, and Catharanthus roseus L. pollen grain samples were collected from each site ensuring that availability of all selected plants occurred at all sites. Different staining methods, using aceto-orcein (AO), Alexander's (AS), 2,3,5 triphenyl tetrazolium chloride (TTC), and Lugol's (LS) stains, were followed to evaluate pollen viability. The study revealed that among all plant species, C. coronarium showed the minimum pollen viability with AO and TTC stains at S-1, S-2, and S-3 while T. erecta with AO and C. cyanus with TTC at S-4. P. somniferum showed minimum pollen viability with AS at all sites and with LS at S-3 and S-4 while R. indica and V. pulchella with LS at S-1 and 2, respectively. All plant species have shown maximum pollen viability using AO stain at all sites. TTC was found to be the effective staining method that resulted in minimum pollen viability for all plant species at all sites except for Alcea rosea at S-2 and 3 and P. somniferum at S-2 which showed minimum pollen viability with LS and AS, respectively. The association between increased EMR power density and reduced pollen viability across different sites points towards the harmful effects of EMR on plant reproduction.

Plants interact closely with arbuscular mycorrhizal (AM) fungi. They allocate photosynthates to AM fungi in exchange for nutrients, thereby influencing plant fitness. Although plant phenotypes result from multiple traits constrained by trade-offs, the effects of AM fungi on plants are often studied using one trait. Plant response to AM fungi therefore needs to be analysed using multiple traits. Four Asteraceae species were inoculated with ten AM fungal strains using a factorial design in the greenhouse. The effect of AM fungal inoculation and their taxonomic identity on plants vegetative and reproductive traits were assessed. The predictability of the effects was evaluated based on AM fungal phylogenetic relatedness. The effect of the inoculation depended on the trait considered. Compared with the non-inoculated control, biomass allocation to roots decreased, while allocations to shoots or reproduction increased depending on the AM fungi or the plant. Significant differences were observed among AM fungi inoculates used, whether looking at separate traits, trade-offs between vegetative or reproductive growth, and the trait syndrome. In Centaurea cyanus, changes in plant phenotype were associated with the phylogenetic distance between AM fungi. These results underline the importance of using multi-trait approaches to understand AM fungal effects on plant phenotype. In accordance with the holobiont concept, the outcomes of this interaction depended on both the host plant and the AM fungus involved. It contributes to a better understanding of the biological effectors shaping the reaction norm (i.e., the range of phenotypic variation of a given host genotype) within the plant holobiont.

The aim of this study was to determine the optimal conditions for copigmentation and encapsulation of anthocyanins extracted from blue and pink cornflower (Centaurea cyanus L.) flowers and to produce encapsulates resistant to environmental factors. Extracts rich in anthocyanins were encapsulated using spray-drying and sublimation techniques. Baicalin and chlorogenic acid were successfully used as copigmentation agents for blue and pink cornflower anthocyanins. The extracts and encapsulates obtained were subjected to stability tests to assess the stability of color and changes in total anthocyanins content, total phenolic compounds content, and antioxidant activity under exposure to high temperature and UV radiation. The developed encapsulation method effectively protects anthocyanins from adverse environmental conditions. The obtained preparations were characterized by a high content of anthocyanins and phenolic compounds as well as a strong antioxidant potential. The highest stability was demonstrated by anthocyanin encapsulates isolated from the pink flowers of the cornflower, obtained by spray-drying with the addition of a copigment (chlorogenic acid or baicalin) and with a weight ratio of anthocyanin extract to carrier of 1:10. The results of this study suggest that anthocyanin preparations from cornflower, after encapsulation and copigmentation with baicalin or chlorogenic acid, can be used as stable colorants in the food industry as well as functional ingredients providing high levels of antioxidant activity.

A polyvinyl alcohol (PVA) matrix hydrogel loaded with Centaurea cyanus extract was created for transdermal wound healing. Secondary metabolites, antibacterial properties, and the cytotoxicity of C. cyanus extract were investigated. The secondary metabolite profiles of the extract were determined by liquid chromatography-mass spectrometry (LC-MS) technique. It was determined that the extract has metabolites such as quinic acid, caffeoylquinic acid, kaempferol, etc., which contribute to the steps of wound healing. The extract had significant activity against Staphylococcus aureus when compared with ampicillin antibiotic and showed an inhibition zone of 16.9 mm ± 0.8, whereas ampicillin's inhibition zone was 15.8 mm ± 0.8. The extract did not exhibit cytotoxic effects on 3T3-L1 (CL173) healthy skin fibroblasts, maintained cell viability for 72 h, and exhibited a 19% proliferative effect. Fourier-transform infrared spectroscopy, scanning electron microscopy, ultraviolet visible spectrophotometer, tensile strength analyses, in vitro release, and physicochemical tests were conducted. It was seen that the surfaces of the samples are smooth and homogeneous, patches had a significant amount of water absorption capacity, and 79% of the extract was released within the first 24 h of application; consequently, these results indicate that C. cyanus might be used in wound healing with its antibacterial, growth-promoting properties.

An extensive study was undertaken using the petals of cornflower (Centaurea cyanus [Cyani flos]) flowers in yogurt production as a source of dietary fiber and antioxidant compounds, and as a natural dye, taking into account a 21-d refrigerated storage period. An additional aim of the study was to use cornflower petals in natural form rather than an extract. Four forms of cornflower petals were tested: fresh, dried, frozen, and freeze-dried. In terms of physicochemical properties, including the amount of dietary fiber and bioactive compounds and antioxidant status, the freeze-dried form proved most beneficial. Two variants of yogurts were made, one without the addition of cornflower petals (control) and one with cornflower. The yogurts were stored for 21 d and analyzed every 7 d (at 0, 7, 14, and 21 d). In total, 4 forms of cornflower petals, 3 batches of bulk cow milk, and 288 yogurt samples were analyzed. Freeze-dried cornflower petals added to yogurt contributed to a significant increase in the content of total protein (by ∼4%), fiber (from 0.00 to 0.56 g/100 g), and selected bioactive compounds, including AA (by ∼2% in total), vitamin C (over 3-fold), and phenolic (by ∼16% in total) and mineral (on average by 8%) compounds, as well antioxidant activity. The presence of antioxidant compounds not only in the processed milk (sulfur AA, whey proteins [especially β-LA], vitamins A, E, and C, or β-carotene) but also in the petals (sulfur AA, vitamin C, and phenolic compounds) contributed to a significant increase in the antioxidant activity of fresh yogurt with cornflower (d 0 of storage; i.e., ferric reducing antioxidant power [FRAP] increased by 18%, 2,2-diphenyl-1-picrylhydrazyl by 50%, and 2,2'-azinobis-(3-ethyl-benzothiazoline-6-sulfonic acid) [ABTS] by 60%), in comparison with the control yogurt. Significant changes in the content of selected bioactive compounds occurred during the 21-d storage, which affected the antioxidant activity (i.e., FRAP and ABTS increased by 20%). In addition, Fourier-transform infrared (FTIR) spectroscopy analyses of the yogurts showed mainly changes in the intensity of vibrations characteristic of this type of product, associated with polysaccharide structures, as well as vibrations associated with protein structures contained in dietary fiber. The regions with the most pronounced changes in the intensity of the bands were ∼3,300, 1,640, 1,550, and 1,240 cm[-1], and there were noticeable changes at ∼1,030 cm[-1]. The maxima also correspond to the vibrations of C=O groups, amide bands, and the polysaccharide fraction, as well as stretching vibrations of the hydroxylic group. The analyses conducted using FTIR spectroscopy demonstrated that the product was highly stable during the refrigerated storage, as reflected in particular by the vibrations in the spectral region below 1,000 cm[-3].

Centaurea cyanus L. is a common field weed in Eastern Europe but only in Poland biotypes of this species with resistance to acetolactate synthase (ALS) inhibitors have been confirmed. This phenomenon is constantly developing and spreading to consecutive regions of Poland. This study aimed to assess the response of selected Polish C. cyanus populations to tribenuron-methyl and to analyse the genetic variability of the ALS gene of C. cyanus populations resistant to ALS inhibitors. Between 2017 and 2021, 13 seed samples were collected from eastern Poland and a dose-response study with tribenuron-methyl was performed. Eleven populations resistant to tribenuron-methyl were identified. All populations from this study as well as 6 additional resistant populations characterised in the previous dose-response studies were subjected to molecular analysis of the ALS gene. Target-site resistance due to mutations P197S, P197Q, P197T and P197A were identified in 8 populations from Warmia-Masuria and Podlaskie provinces. This is the first case of target-site resistance (TSR) in C. cyanus confirmed by sequencing of the ALS gene. Moreover in some resistant plants, ten changes in the amino acid ALS sequence were identified in comparison to those in the susceptible ones. In none of the populations were all mutations detected in the same individual. The highest frequency of mutations was detected in Warmia-Masuria province. Some C. cyanus populations resistant to ALS inhibitors showed hormesis effect concerning shoot fresh weight after tribenuron-methyl treatment. Stimulation due to half the recommended dose of tribenuron-methyl was the highest and the difference between untreated and treated plants was statistically significant in two populations from Warmia-Masuria and in one from Podlaskie province.

Gomphrena celosioides, popularly known as perpétua, perpétua brava, bachelor´s button and prostate globe amarahth, is used for the treatment of urinary tract disorders, kidney stones, for skin diseases, infectious diseases, gastrointestinal and respiratory conditions. Rich in phenolic acids and flavonoids, this plant has therefore a potential for use in cancer prevention. Given the above, the present research aimed to evaluate the carcinogenic effect of the ethanolic extract of G. celosioides (EEGc) in an alternative model of Drosophila melanogaster and the genotoxic and antigenotoxic effects in Swiss mice. The larval survival test and the detection of epithelial tumor clones were performed in D. melanogaster. The tested EEGc concentrations were 0.96, 1.92, 3.85 and 7.70 mg/mL. In Swiss mice, the genotoxicity and antigenotoxicity of doses of 100, 1,000 and 2,000 mg/Kg were evaluated. The results showed that EEGc at a concentration of 7.70 mg/mL reduced (p<0.05) larval survival. However, EEGc was not carcinogenic, and the lowest concentration (0.96 mg/mL) prevented (p<0.05) the basal occurrence of epithelial tumors. In mice, EEGc at the highest dose (2,000mg/Kg) increased the frequency of genomic lesions (p<0.05). Yet, none of the doses caused chromosomal lesions (p>0.05). When associated with cyclophosphamide, EEGc was antigenotoxic (p<0.05). The percentages of reduction of genomic damage ranged from 33.39 to 63.23% and of chromosomal damage from 20.00 to 77.19%. In view of the above, it is suggested that EEGc is not carcinogenic, has an antigenotoxic effect and chemopreventive properties.

This study aimed to compare the impact of iodosulfuron-methyl-sodium and an iodosulfuron-based herbicidal ionic liquid (HIL) on the microbiomes constituting the epiphytes and endophytes of cornflower (Centaurea cyanus L.). The experiment involved biotypes of cornflower susceptible and resistant to acetolactate synthase inhibition, examining potential bacterial involvement in sulfonylurea herbicide detoxification. We focused on microbial communities present on the surface and in the plant tissues of roots and shoots. The research included the synthesis and physicochemical analysis of a novel HIL, evaluation of shifts in bacterial community composition, analysis of the presence of catabolic genes associated with sulfonylurea herbicide degradation and determination of their abundance in all experimental variants. Overall, for the susceptible biotype, the biodiversity of the root microbiome was higher compared to shoot microbiome; however, both decreased notably after herbicide or HIL applications. The herbicide-resistant biotype showed lower degree of biodiversity changes, but shifts in community composition occurred, particularly in case of HIL treatment.

This study demonstrated the effects of adding specific proportions of vermiculite (VMT: 0%, 10%, and 20%) and earthworm casts (EWCs: 0%, 10%, and 20%) on the physico-chemical properties of composted green waste (CGW), and the impacts of amended CGW as growth media on the growth of three common ornamental plants (Dahlia pinnata Cav. [dahlia], Centaurea cyanus L. [cornflower], and Consolida ajacis [L.] Schur [delphinium]). Compared with Treatment T1 (CK), the addition of 10% VMT and 20% EWCs greatly (p < 0.05) increased the total porosity, aeration porosity, water-holding porosity, total nitrogen, available phosphorus, available potassium, and organic matter of CGW by 9%, 35%, 4%, 18%, 27%, 13%, and 33%, respectively. In addition, this pattern increased (p < 0.05) the total fresh biomass, total chlorophyll content, and root length of dahlias by 9%, 19%, and 27%, respectively; those of cornflowers by 17%, 30%, and 29%, respectively (p < 0.05); and those of delphiniums by 23%, 14%, and 63%, respectively. Therefore, the amended CGW supplemented with 10% VMT and 20% EWCs was an ideal growth medium for the three plants.

Delayed sowing of winter cereals or unfavorable weather conditions in autumn may make it impossible to carry out herbicide treatment in autumn. In such cases, weed control should be started in the spring. During this time, the plantation should be protected as effectively as possible because the weeds are at an advanced stage of growth. Therefore, they are less sensitive to applied herbicides. In the treatment, it is worth using a mixture of different mechanisms of action. Studies were conducted to evaluate the effectiveness of a band of tribenuron-methyl, and MCPA applied as soluble granules in spring control of dicotyledonous in winter cereals. The biological efficacy of herbicides was estimated in the 25 field experiments on winter cereals in Poland. Postemergence, a spring application of tribenuron-methyl + MCPA, effectively controls the majority of weed species present in spring: Anthemis arvensis, Brassica napus, Capsella bursa-pastoris, Centaurea cyanus, Lamium purpureum, Matricaria chamomilla, Tripleurospermum inodorum, Stellaria media and Thlaspi arvense. Satisfactory control was confirmed for Veronica persica, Viola arvensis, and Galium aparine. Tribenuron-methyl with MCPA is recommended for application to winter cereals in spring. To prevent the development of resistance in weeds, it is advantageous to combine two active substances.