Nano silica's role in regulating heavy metal uptake in Calendula officinalis.

BACKGROUND: Soil contamination with heavy metals poses a significant threat to plant health and human well-being. This study explores the potential of nano silica as a solution for mitigating heavy metal uptake in Calendula officinalis. RESULTS: Greenhouse experiments demonstrated, 1000 mg•kg- 1 nano silica caused a 6% increase in soil pH compared to the control treatment. Also in 1000 mg. kg- 1 nano silica, the concentrations of available Pb (lead), Zn (zinc), Cu (copper), Ni (nickel), and Cr (chromium) in soil decreased by 12%, 11%, 11.6%, 10%, and 9.5%, respectively, compared to the control. Nano silica application significantly reduces heavy metal accumulation in C. officinalis exposed to contaminated soil except Zn. In 1000 mg.kg- 1 nano silica shoots Zn 13.28% increased and roots Zn increased 13% compared to the control treatment. Applying nano silica leads to increase the amount of phosphorus (P) 25%, potassium (K) 26% uptake by plant, In 1000 mg.kg - 1 treatment the highest amount of urease enzyme activity was 2.5%, dehydrogenase enzyme activity, 23.6% and the highest level of alkaline phosphatase enzyme activity was 13.5% higher than the control treatment. CONCLUSION: Nano silica, particularly at a concentration of 1000 mg.kg - 1, enhanced roots and shoots length, dry weight, and soil enzyme activity Moreover, it increased P and K concentrations in plant tissues while decreasing heavy metals uptake by plant.

Modified diatomite for soil remediation and its implications for heavy metal absorption in Calendula officinalis.

BACKGROUND: Among different adsorbents, natural and inorganic compounds such as diatomite are important and advantageous in terms of high efficiency and cost-effectiveness, and function in stabilizing heavy metals in the environment. Calendula officinalis, a plant known as a high accumulator of heavy metals, was cultivated in soil treated with varying concentrations of modified diatomite to demonstrate the efficiency of modified diatomite in stabilizating of heavy metals in soils, RESULTS: The modification of diatomite aimed to enhance Calendula officinalis adsorptive properties, particularly towards heavy metals such as lead (Pb), Zinc (Zn), Chromium (Cr), Nickle (Ni), and Copper (Cu), common contaminants in industrial soils. The experimental design included both control and treated soil samples, with assessments at regular intervals. Modified diatomite significantly decreased the bioaccumulation of heavy metals in contaminated soils except Zn, evidenced by decreased DTPA extractable heavy metals in soil and also heavy metal concentrations in plant tissues. Using 10% modified diatomite decreased 91% Pb and Cu, 78% Cr, and 79% Ni concentration of plants compared to the control treatment. The highest concentration of Zn in plant tissue was observed in 2.5% modified diatomite treatment. Remarkably, the application of modified diatomite also appeared to improve the nutrient profile of the soil, leading to enhanced uptake of key nutrients like phosphorus (P) 1.18%, and potassium (K) 79.6% in shoots and 82.3% in roots in Calendula officinalis. Consequently, treated plants exhibited improved growth characteristics, including shoots and roots height of 16.98% and 12.8% respectively, and shoots fresh and dry weight of 48.5% and 50.2% respectively., compared to those in untreated, contaminated soil. CONCLUSION: The findings suggest promising implications for using such amendments in ecological restoration and sustainable agriculture, particularly in areas impacted by industrial pollution.

In vitro anticancer efficacy of Calendula Officinalis extract-loaded chitosan nanoparticles against gastric and colon cancer cells.

OBJECTIVE: This study assessed the anticancer activities of Calendula officinalis-loaded chitosan nanoparticles in gastric and colon cancer cells compared with fibroblast cells and examined the balance between ROS and antioxidants. METHODS: Considering this information, we synthesized Calendula officinalis-loaded chitosan nanoparticles (CO-CSNPs) via the ionic gelation method. Their characterizations were carried out with ZetaSizer, UV-Vis, FTIR and SEM devices including size, morphology and surface zeta potential analysis, loading capacity, encapsulation efficiency, in vitro drug release, and chemical interactions. The anticancer activities of CO, CSNPs, and CO-CSNPs were tested against AGS, Caco-2, and normal NIH-3T3 cells using an XTT assay. The anticancer effects were evaluated using DAPI staining, scratch assay, reactive oxygen species (ROS) detection and the CUPRAC method on cellular and non-cellular processes that promote anticancer mechanisms. RESULTS: Results showed that CO and CO-CNPs exhibited anticancer activity against AGS and Caco-2. Further, the formulation of CO with CSNPs enhanced the anticancer activity of CO while having no cytotoxicity on NIH-3T3. DAPI staining, scratch assay, ROS, and CUPRAC method confirmed the anticancer activity of CO and CO-CSNPs, which resulted in a reduction in the number of apoptotic cells, inhibited migration, triggered apoptotic pathway via ROS, and higher antioxidant activity. CONCLUSIONS: The results of the study indicate that CO-CSNPs are a promising therapeutic formulation for gastric and colon cancer treatment. We consider that this study will lead to the investigation of molecular mechanisms of CO-CSNPs in cancer treatment and their investigation in clinical studies.

Whey Protein Isolate as a Substrate to Design Calendula officinalis Flower Extract Controlled-Release Materials.

The use of natural active substances and the development of new formulations are promising directions in the cosmetic and pharmacy industries. The primary purpose of this research was the production of microparticles based on whey protein isolate (WPI) and calcium alginate (ALG) containing Calendula officinalis flower extract and their incorporation into films composed of gelatin, WPI, and glycerol. Both swollen and dry microparticles were studied by optical microscopy and their sizes were measured. Water absorption by the microparticles, their loading capacity, and the release profile of flower extract were also characterized. The films were analyzed by mechanical tests (Young's modulus, tensile strength, elongation at break), swelling capacity, contact angle, and moisture content measurements. The presented data showed that the active ingredient was successfully enclosed in spherical microparticles and completely released after 75 min of incubation at 37 °C. The incorporation of the microparticles into polymer films caused a decrease in stiffness and tensile strength, simultaneously increasing the ductility of the samples. Moreover, the films containing microparticles displayed higher swelling ability and moisture content compared to those without them. Hence, the materials prepared in this study with Calendula officinalis flower extract encapsulated into polymeric microspheres can be a starting point for the development of new products intended for skin application; advantages include protection of the extract against external factors and a controlled release profile.

The Mediterranean Species Calendula officinalis and Foeniculum vulgare as Valuable Source of Bioactive Compounds.

Research studies on plant secondary metabolites have increased over the last decades as a consequence of the growing consumer demand for natural products in pharmaceutics and therapeutics, as well as in perfumery and cosmetics. In this perspective, many Mediterranean plant species could be an appreciated source of bioactive compounds with pharmacological and health-promoting properties, including antioxidant, antimicrobial, antiviral, anti-inflammatory, and antitumor ones. Calendula officinalis and Foeniculum vulgare are commercially important plants of the Mediterranean flora, with great therapeutic use in the treatment of many disorders since ancient times, and are now listed in several world pharmacopoeias and drug agencies. The present review offers an overview of the main phytochemicals, phenols, terpenes, and alkaloids, biosynthesized in C. officinalis and F. vulgare, both species endemic to the Mediterranean region. Further, all current knowledge and scientific data on taxonomic classification, botanical description, traditional uses, pharmacological studies, and potential toxicity of both species were reported. The principal aim of this review is to point out the prospective use of C. officinalis and F. vulgare as valuable reservoirs of beneficial plant-derived products with interesting biological properties, also providing suggestions and future challenges for the full exploitation of these two Mediterranean species for human life improvement.

Variability in growth and biosynthetic activity of Calendula officinalis hairy roots.

Calendula officinalis is a widespread medicinal plant with a sufficiently well-studied chemical composition. Secondary metabolites synthesized by C.officinalis plants have pharmacological value for treating numerous diseases, and various types of aseptic in vitro cultures can be used as a source of these compounds. From this perspective, hairy roots attract considerable attention for the production of bioactive chemicals, including flavonoids with antioxidant activity. This paper shows the possibility of C.officinalis hairy roots obtaining with 100% frequency by Agrobacterium rhizogenes genetic transformation. Hairy root lines differed in growth rate and flavonoid content. In particular, flavonoids were accumulated in the amount of up to 6.68 ± 0.28 mg/g of wet weight. Methyl jasmonate in the concentration of 10 µM inhibited root growth to a small extent but stimulated the synthesis of flavonoids. The antioxidant activity and the reducing power increased in the roots grown in the medium with methyl jasmonate. The strong correlation of antioxidant activity and reducing power with flavonoid content was detected. The influence of extraction conditions on the content of flavonoids in the extracts and their bioactivity was determined. The potent reducing activity of extracts from hairy roots allowed the production of silver nanoparticles, which was confirmed by transmission electron microscopy.

Identification of Flavonoids, Antioxidant and Antiproliferative Activity of Aqueous Infusions of Calendula officinalis L., Chelidonium majus L., Teucrium chamaedrys L. and Alchemilla vulgaris L.

Research background: The current changes in the global economy, characterised by the climate crisis and the economic and health impact of the COVID-19 pandemic, have led to a significant demand for medicinal herbs. This trend is expected to increase significantly by 2050. In this study, we investigated the biopotential of aqueous infusions of four medicinal plants: Calendula officinalis, Chelidonium majus, Teucrium chamaedrys and Alchemilla vulgaris. Experimental approach: The flavonoid analysis of the aqueous infusions of the selected plants was carried out using the RP-HPLC technique. The antiproliferative activity of the prepared aqueous plant infusions was analysed against three human cancer cell lines (MDA-MD-231, T24 and A549), while the antioxidant potential was measured using three antioxidant methods (DPPH, FRAP and Rancimat assay). Results and conclusions: T. chamaedrys had the highest total phenolics (expressed as GAE (2061±42) mg/L), free radical scavenging activity (IC50=1.9 mg/mL) and Fe(III) reducing antioxidant power (expressed as FeCl2 (9798±27) mg/L). At a concentration of 1 mg/mL, the antiproliferation of T24 by C. majus was 96 % and of MDA-MD-231 cells by A. vulgaris was 75 % after 72 h. After principal component analysis, T. chamaedrys and C. majus were grouped together. Quercetin glucoside and antioxidant capacity (DPPH) contributed the most to differentiate these infusions from the other two. Novelty and scientific contribution: This study represents a comparative analysis of the biopotential of four medicinal plants. A new RP-HPLC method was developed to separate the flavonoids in the herbal infusions. This is the first report on the presence of kaempferol-3-O-rutinoside in C. officinalis and isorhamnetin-3-O-rutinoside in A. vulgaris aqueous infusion. For the first time, C. majus has been shown to contribute to the oxidative stability of edible oil. Furthermore, this is the first comparative study on the antiproliferative activity of selected medicinal plants against the cell lines MDA-MD-231, T24 and A549.

Green and eco-friendly biosynthesis of zinc oxide nanoparticles using Calendula officinalis flower extract: Wound healing potential and antioxidant activity.

This study aimed to produce zinc oxide nanoparticles with Calendula officinalis flower extract (Co-ZnO NPs) using the green synthesis method. In addition, the antioxidant and wound healing potential of synthesized ZnO NPs were evaluated. The absorbance band at 355 nm, which is typical for ZnO NPs, was determined from the UV-Vis absorbance spectrum. The energy-dispersive X-ray spectroscopy (EDS) measurements revealed a high zinc content of 42.90%. The x-ray diffractometer data showed Co-ZnO NPs with an average crystallite size of 17.66 nm. The Co-ZnO NPs did not have apparent cytotoxicity up to 10 µg/mL (IC50 25.96 µg/mL). C. officinalis ZnO NPs showed partial cell migration and percent wound closure (69.1%) compared with control (64.8%). In addition, antioxidant activities of Co-ZnO NPs with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2 diphenyl-1 picrylhydrazil (DPPH) were evaluated and radical scavenging activity of 33.49% and 46.63%, respectively, was determined. These results suggest that C. officinalis extract is an effective reducing agent for the green synthesis of ZnO NPs with significant antioxidant and wound healing potential.

Prenylated acetophenones from the roots of Calendula officinalis and their anti-inflammatory activity.

Calendula officinalis is a medicinal plant in the Asteraceae family, and it has a broad range of biological activities. In this study, we focused on the roots of C. officinalis, which have remarkable anti-inflammatory properties. By using a bioassay-guided fractionation approach, prenylated acetophenones 1 and 2-of which 1 was previously unknown-were isolated, and their structures were determined by spectroscopic analysis. Both compounds decreased lipopolysaccharide-stimulated NO production in J774.1 cells. This study could lead to the use of the Calendula roots as a natural source of inflammatory mediators.

Effects of Calendula officinalis and Capsicum annum glycolic extracts on planktonic cells and biofilms of multidrug-resistant strains of Klebsiella pneumoniae and Pseudomonas aeruginosa.

Empirical knowledge of natural plant extracts is increasingly proving to be a promising field. The effect of Calendula officinalis L. (CO) and Capsicum annum (CA) glycolic extracts (GlExt) have potential that should be further developed in microbial tests. The effect of CO-GlExt and CA-GlExt was evaluated on eight multidrug-resistant clinical strains of Klebsiella pneumoniae and Pseudomonas aeruginosa, as well as collection strains for each bacterial. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extract were determined in comparison with 0.12% chlorhexidine. The tests were performed on single species biofilms, at 5 min and 24 h, using the MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay. The MIC and MBC of the extract ranged from 1.56 to 50 mg mL-1 for all strains evaluated. Analysis of the MTT assay revealed a strong antimicrobial potential of CA-GlExt, comparable to chlorhexidine. The findings suggest that CA-GlExt is effective against multidrug-resistant strains of K. pneumoniae and P. aeruginosa in planktonic state and biofilms.

Chemical Composition and in Vitro Antioxidant, Anti-Alzheimer, Anti-Diabetic, Anti-Tyrosinase, and Antimicrobial Properties of Essential Oils and Extracts Derived from Various Parts of the Algerian Calendula Suffruticosa Vahlsubsp. boissieri Lanza.

Calendula suffruticosa Vahl subsp. boissieri Lanza is well-known for its medicinal properties in northeastern Algeria. As far as literature has been able to prove, no study has attempted to make a phytochemical or biological activity evaluation (antioxidants, enzyme inhibitors and antimicrobial potential). This work intends to evaluate, for the first time, the chemical constituents and study the previously mentioned biological activities of C. suffruticosa boissieri essential oil and different sections (flowers, leaves, roots) as well as the effect of changing the solvent (ethanol 70 %) and (methanol 70 %) on these activities. The essential oil of aerial parts of this plant was investigated using GC/MS, and 45 compounds were discovered, accounting for 98.01 % of the essential oil, including 23 monoterpenes, 6 sesquiterpenes, 12 diterpenes, 1 coumarin, 3 alkanes, methyl-cyclohexane (23.73 %), limonene (25.02 %), and o-cymene (13.20 %). Five methods were used to study the antioxidant activity (ABTS, DPPH, CUPRAC, reducing power, and ß-carotene bleaching assay), where the results were impressive, especially for the essential oil. In addition, the hydroethanolic solvent (70 %) was found to be the most effective solvent for extraction in general compared to the hydromethanolic solvent (70 %). The extracts and essential oils of C. suffruticosa boissieri also showed a strong inhibiting ability against cholinesterase, tyrosinase, anti-α-amylase, α-glucosidase, and antimicrobials, a very valuable antioxidant, which is a real discovery. Based on these results, it can be said that this plant has important biological activities, so it can be used in the phytotherapy, food, or pharmaceutical sectors.

Burkholderia cepacia CS8 improves phytoremediation potential of Calendula officinalis for tannery solid waste polluted soil.

Microbes have shown potential for the bioremediation of tannery waste polluted soil. During our previous study, it was observed that heavy metal resistant Burkholderia cepacia CS8 augmented growth and phytoremediation capability of an ornamental plant. Objective of the present research work was to evaluate the capability of B. cepacia CS8 assisted Calendula officinalis plants for the phytoremediation of tannery solid waste (TSW) polluted soil. The TSW treatment significantly reduced growth attributes and photosynthetic pigments in C. officinalis. However, supplementation of B. cepacia CS8 which exhibited substantial tolerance to the TSW amended soil, augmented growth traits, carotenoid, proline, and antioxidant enzymes level in C. officinalis under toxic and nontoxic regimes. Inoculation of B. cepacia CS8 augmented plant growth (shoot length 13%, root length 11%), physiological attributes (chlorophyll a 14%, chlorophyll b 17%), antioxidant enzyme activities (peroxidase 24%, superoxide dismutase 31% and catalase 19%), improved proline 36%, phenol 32%, flavonoids 14% and declined malondialdehyde (MDA) content 15% and hydrogen peroxide (H2O2) level 12% in C. officinalis at TSW10 stress compared with relevant un-inoculated plants of TSW10 treatment. Moreover, B. cepacia CS8 application enhanced labile metals in soil and subsequent metal uptake, such as Cr 19%, Cd 22%, Ni 35%, Fe 18%, Cu 21%, Pb 34%, and Zn 30%, respectively in C. officinalis plants subjected to TSW10 stress than that of analogous un-inoculated treatment. Higher plant stress tolerance and improved phytoremediation potential through microbial inoculation will assist in the retrieval of agricultural land in addition to the renewal of native vegetation.

During the current study, it was observed that combination of Calendula officinalis and metal tolerant Burkholderia cepacia CS8 not only improved plant growth but also helped phyto-extraction of pollutants present in the tannery solid waste polluted soil. According to our information, research work describing the phytoremediation potential of native metal tolerant microbes and ornamental plants has not been reported in Pakistan.

Polyacrylamide Hydrogel Containing Calendula Extract as a Wound Healing Bandage: In Vivo Test.

Hydrogel is a biomaterial widely used in several areas of industry due to its great biocompatibility and adaptability to biological tissues. In Brazil, the Calendula plant is approved by the Ministry of Health as a medicinal herb. It was chosen to be incorporated in the hydrogel formulation because of its anti-inflammatory, antiseptic and healing effects. This study synthesized polyacrylamide hydrogel containing calendula extract and evaluated its efficiency as a bandage for wound healing. The hydrogels were prepared using free radical polymerization and characterized by Scanning Electron Microscopy, swelling analysis and mechanical properties by texturometer. The morphology of the matrices showed large pores and foliaceous structure. In vivo testing, as well as the evaluation of acute dermal toxicity, was conducted using male Wistar rats. The tests indicated efficient collagen fiber production, improved skin repair and no signs of dermal toxicity. Thus, the hydrogel presents compatible properties for the controlled release of calendula extract used as a bandage to promote cicatrization.

Catechol-O-methyltransferase Inhibitors from Calendula officinalis Leaf.

Calendula officinalis is commonly known as marigold and its flowers are used in herbal medicines, cosmetics, perfumes, dyes, pharmaceutical preparations, and food products. However, the utility of its leaves has not been studied in depth. The purpose of the present study was to identify the major compounds in C. officinalis leaves and to determine the inhibitory properties of the isolated compounds toward human catechol-O-methyltransferase (COMT), a key neurotransmitter involved in Parkinson's disease and depression. We isolated and identified ten compounds, including two phenylpropanoids and seven flavonoids, from C. officinalis leaf extracts, of which four flavonoids were identified from C. officinalis leaves for the first time. Eight compounds exhibited COMT inhibitory activities with IC50 values of less than 100 µM. Our results indicate that compounds in C. officinalis leaves are potentially effective for preventing Parkinson's disease and depression. Thus, C. officinalis leaves may hold promise as dietary supplements.

Multivariate selection mediated by aridity predicts divergence of drought-resistant traits along natural aridity gradients of an invasive weed.

Geographical variation in the environment underpins selection for local adaptation and evolutionary divergence among populations. Because many environmental conditions vary across species' ranges, identifying the specific environmental variables underlying local adaptation is profoundly challenging. We tested whether natural selection mediated by aridity predicts clinal divergence among invasive populations of capeweed (Arctotheca calendula) that established and spread across southern Australia during the last two centuries. Using common garden experiments with two environmental treatments (wet and dry) that mimic aridity conditions across capeweed's invasive range, we estimated clinal divergence and effects of aridity on fitness and multivariate phenotypic selection in populations sampled along aridity gradients in Australia. We show that: (1) capeweed populations have relatively high fitness in aridity environments similar to their sampling locations; (2) the magnitude and direction of selection strongly differs between wet and dry treatments, with drought stress increasing the strength of selection; and (3) differences in directional selection between wet and dry treatments predict patterns of clinal divergence across the aridity gradient, particularly for traits affecting biomass, flowering phenology and putative antioxidant expression. Our results suggest that aridity-mediated selection contributes to trait diversification among invasive capeweed populations, possibly facilitating the expansion of capeweed across southern Australia.

Chemical Variability of Hexane Extracts from Five Subspecies of Calendula suffruticosa from Spain.

The chemical profile of the hexane extracts of the subspecies carbonellii, greuteri, marginata, trialata, and vejerensis of Calendula suffruticosa growing in Spain, herein described for the first time, were studied to access their value as a chemo taxonomical tool and search for potentially useful compounds. The subsp. greuteri and carbonellii showed higher extract yields. Terpenoids were the most abundant chemical class in subsp. carbonellii, greuteri, trialata, and vejerensis, while alkanes were the most abundant in subsp. marginata. Differences in chemical constituents were identified among the subspecies of C. suffruticosa analysed, which the PCA can prove. The subsp. trialata and greuteri showed more significant phytochemical similarity, which might indicate genetic proximity between these two subspecies. C. suffruticosa subsp. marginata presented the fewest number of compounds and in the smallest quantities, and C. suffruticosa subsp. vejerensis presented the largest number, however, both showed no alcohols. Furthermore, some of the compounds found in significant amounts are known for their pharmacological and nutraceutical properties, denoting potential use.

In vitro and in vivo evaluation of nanofibre mats containing Calendula officinalis extract as a wound dressing.

OBJECTIVE: The present study aims to create Calendula officinalis-loaded nanofibre-based wound dressing materials to enhance the wound healing process. Calendula officinalis is an annual herb native to the Mediterranean region. It is antipyretic, antifungal, antioedema, antidiabetic, anti-inflammatory (wound, oral and pharyngeal mucosa), antispasmodic, treats chronic ocular surface diseases, acts as a stimulant and a diaphoretic. It is also used in the prevention of acute dermatitis, and in the treatment of gastrointestinal ulcers, wounds and burns. METHOD: Electrospinning is an effective method for creating nano- and microfibres for biomedical applications. Calendula officinalis (CA) of various concentrations 5%, 10% and 15%)-loaded polyvinyl alcohol (PVA)/sodium alginate (SAlg) nanofibre mats were successfully produced via blend electrospinning. Nanofibre mats were evaluated using: scanning electron microscopy (SEM); Fourier transform infrared spectroscopy (FTIR) analysis; gel content; water vapour transmission rate (WVTR); swelling ratio; in vitro drug release studies; viability evaluation (cell culture and MTT assay); and an in vivo study using male Wistar rats. Rats were divided into three groups (n=3). In each group, rats were inflicted with five full-thickness wounds on the back and were treated with sterile gauze (control), PVA/SAlg nanofibre dressing (CA-free control), PVA/SAlg/CA5%, PVA/SAlg/CA10%, and PVA/SAlg/CA15% nanofibre dressing. RESULTS: Results showed that the obtained fibres were smooth with no surface aggregates, indicating complete incorporation of Calendula officinalis. The release of Calendula officinalis from loaded PVA/SAlg fibre mats in the first four hours was burst released and then was constant. PVA/SAlg and PVA/SAlg/CA nanofibres were not toxic to L929 mouse fibroblasts and supported cell attachment and proliferation. The results of the in vivo study showed that the PVA/SAlg/CA10% nanofibre dressing had a higher full-thickness wound healing closure rate compared with the control group on days seven, 14 and 21 after treatment. CONCLUSION: The results of this evaluation showed that PVA/SAlg/CA nanofibrous mats could be a candidate as an effective wound dressing; however, the percentage of CA in this compound needs further investigation.

Modulation of Steroid and Triterpenoid Metabolism in Calendula officinalis Plants and Hairy Root Cultures Exposed to Cadmium Stress.

The present study investigated the changes in the content of steroids and triterpenoids in C. officinalis hairy root cultures and plants exposed to cadmium stress. The observed effects included the content and composition of analyzed groups of compounds, particularly the proportions among individual sterols (e.g., stigmasterol-to-sitosterol ratio), their ester and glycoside conjugates. The total sterol content increased in roots (by 30%) and hairy root culture (by 44%), whereas it decreased in shoots (by 15%); moreover, these effects were inversely correlated with Cd-induced growth suppression. Metabolic alterations of sterols and their forms seemed to play a greater role in the response to Cd stress in roots than in shoots. The symptoms of the competition between general metabolites (sterols) and specialized metabolites (triterpenoids) were also observed, i.e., the increase of the sterol biosynthesis parallel to the decrease of the triterpenoid content in C. officinalis plant roots and hairy root culture, and the inverse phenomenon in shoots. The similarity of the metabolic modifications observed in the present study on C. officinalis plant roots and hairy roots confirmed the possibility of application of plant in vitro cultures in initial studies for physiological research on plant response to environmental stresses.

Marigold Metabolites: Diversity and Separation Methods of Calendula Genus Phytochemicals from 1891 to 2022.

Marigold (Calendula), an important asteraceous genus, has a history of many centuries of therapeutic use in traditional and officinal medicines all over the world. The scientific study of Calendula metabolites was initiated at the end of the 18th century and has been successfully performed for more than a century. The result is an investigation of five species (i.e., C. officinalis, C. arvensis, C. suffruticosa, C. stellata, and C. tripterocarpa) and the discovery of 656 metabolites (i.e., mono-, sesqui-, di-, and triterpenes, phenols, coumarins, hydroxycinnamates, flavonoids, fatty acids, carbohydrates, etc.), which are discussed in this review. The identified compounds were analyzed by various separation techniques as gas chromatography and liquid chromatography which are summarized here. Thus, the genus Calendula is still a high-demand plant-based medicine and a valuable bioactive agent, and research on it will continue for a long time.

Encapsulating Calendula arvensis (Vaill.) L. Florets: UHPLC-HRMS Insights into Bioactive Compounds Preservation and Oral Bioaccessibility.

Wild edible plants, once consumed in times of famine or for health purposes, today represent an interesting dietary supplement, aimed at enriching local dishes and/or formulating healthy nutraceutical products. In fact, the broad content of different, and diversely bioactive, specialized metabolites therein suggests new scenarios of use which, in order to be as functional as possible, must maximize the bioactivity of these compounds while preserving their chemistry. In this context, based on a recent investigation on the metabolic profile of the organs of Calendula arvensis that highlighted that florets are abundant in flavonol glycosides and triterpene saponins, the freeze-drying encapsulation of their alcoholic extract (FE) into maltodextrin (MD) was investigated. FE-MD chemical composition was evaluated using Fourier Transform InfraRed spectroscopy (FTIR), while ultra-high performance liquid chromatography coupled with high-resolution tandem mass spectrometry (UHPLC-HRMS/MS) techniques were employed to unravel FE compound preservation also during in vitro simulated digestion. The establishment of H-bonds between FE compounds and MD hydroxyl groups was in line with FE-MD biocompatibility in Caco-2 cells, while in vitro digestion mostly affected structural integrity and/or diversity. Flavonol compounds underwent deglycosylation and demethylation, while deacylation, beyond oxidation, involved triterpene saponins, which massively preserve their aglycone core.