In vitro antimicrobial, antioxidant and anticancer activities of globe artichoke (Cynara cardunculus var. scolymus L.) bracts and receptacles ethanolic extract

Exploring the ethnopharmacological significance of Cynara scolymus bracts: Integrating metabolomics, in-Vitro cytotoxic studies and network pharmacology for liver and breast anticancer activity assessment

ETHNOPHARMACOLOGICAL RELEVANCE

Liver and breast cancers are the most dominant cancer types with high occurrence rates. Artichoke (Cynara scolymus L.) has been reputed for its traditional use in alleviating many liver and gallbladder ailments beside its anticancer activity against various types of cancer cells.

AIM OF THE STUDY

To demonstrate detailed chemical matrices of the different plant parts and evaluate their cytotoxic activities aiming to unveil the relationship between these activities and the intrinsic metabolites using metabolomic studies, in-vitro experiments and network pharmacology.

MATERIALS AND METHODS

Chemical profiling of extracts from the different plant parts (stems, leaves, bracts and receptacles) was performed using HPLC/QqQ/MS followed by unsupervised chemometric studies. In-vitro cytotoxic potentials of the extracts were evaluated on breast and liver cancer cell line then an OPLS study using linear regression was conducted. Consequently, a network pharmacology analysis on the most bioactive plant organ was applied.

RESULTS

Unsupervised chemometric analysis revealed that kaempferol-3-O-α-L-rhamnopyranoside-7-O-β-D-galacturonopyranoside, chrysoeriol-7-rutinoside and 1-caffeoylquinic acid were responsible for the segregation of the bract (CSB) segregated from the rest of the plant organs. Interestingly, CSB extract possessed the highest potential in-vitro cytotoxic activity against both liver and breast cancer cells (IC50 = 1.65 and 1.77 μg/mL). As expected, the aforementioned biomarkers were observed to be the discriminatory cytotoxic metabolites in the constructed supervised chemometric model. Network pharmacology analysis on CSB revealed 27 liver cancer-related metabolites of which, 1-caffeoylquinic acid was the most enriched one contributing to 13% of the total interactions. Furthermore, 38 target genes were involved, the most enriched of which were Aldo-keto reductase family 1 member B1 (AKR1B10) and interleukin-2 (IL-2). KEGG pathway analysis unveiled 23 significantly related pathways including metabolic pathways that possessed the lowest p-value (1.6E-5).

CONCLUSION

The findings demonstrated that CSB is a significant source of cytotoxic metabolites against breast cancer and liver cancer cell lines, hence, drawing attention to the pharmaceutical and medicinal value of this negligible plant organ and paving the route for insightful research into its exact pharmacological cytotoxic mechanisms.

Globe Artichoke (Cynara scolymus L.) By-Products in Food Applications: Functional and Biological Properties

Globe artichoke (Cynara cardunculus var. scolymus L.) is widely cultivated in the Mediterranean area and Italy is one of the largest producers. A great issue is represented by its high amount of by-product, mainly consisting of external bracts and stems, but also of residual leaves, stalks, roots, and seeds. Artichoke by-products are rich in nutrients (carbohydrates and proteins) and bioactive compounds (polyphenols and terpenes) and represent potential ingredients for foodstuffs, functional foods, and food supplements, due to their functional and biological properties. In fact, artichoke by-products' components exhibit many beneficial effects, such as dyspeptic, prebiotic, antioxidant, anti-inflammatory, antiglycative, antimicrobial, anticarcinogenic, and hypolipidemic properties. Therefore, they can be considered potential food ingredients useful in reducing the risk of developing metabolic and age-related disorders. This work summarizes the economic and environmental impact of the recovery and valorization of artichoke by-products, focusing on rheological, physical, and biological properties of the different components present in each by-product and their different food applications.

Evaluation of the Phenolic Content and the Nutraceutical Potential of Ancestor and Cultivated Artichokes

Wild cardoon (Cynara cardunculus var. sylvestris) is the ancestor of many cultivated forms, including globe artichoke (C. cardunculus var. scolymus). Four organs (receptacles, bracts, leaves and stems) of wild and cultivated artichokes (organic and conventional) were assessed considering their individual phenolic constituents (HPLC-DAD), total phenol-flavonoid content, and pharmaceutical potentials (antibacterial and antioxidant). All three sources of artichokes had the highest concentration of 1,3-dicaffeoylquinic acid (cynarin) in their receptacles and cultivated artichoke receptacles had more cynarin than wild one. On the other hand, receptacles of wild cardoon had the highest 1,5-dicaffeoylquinic acid and caffeic acid than the cultivated ones. Generally, receptacles, stems and leaves of wild cardoon were superior to both cultivated artichokes on antioxidant potential, and total phenol-flavonoid content. The rise in total phenolic content can be attributed to an increase in antioxidant capacity in all artichoke organs. Only the leaves of all different artichokes showed antibacterial activity against Gram-positive bacteria. The investigated wild cardoon was believed to be a true ancestor since a comparison of wild and cultivated varieties revealed similar trends in terms of phenolic profile and biological properties. The nutraceutical industry can profit from this invasive wild cardoon due to their strong antioxidant potential and phenolic content.

Cynara cardunculus L. var. scolymus L. Landrace "Carciofo Ortano" as a Source of Bioactive Compounds

The preservation of agricultural biodiversity and socioeconomic development are relevant both to enhance domestic production and to support innovation. In the search for new biomolecules, we have focused on the "Carciofo Ortano" landrace, growth in the northern part of the Lazio region. Artichoke cultivation generates substantial by-products, including leaves, stems, and roots, which could serve as valuable sources of biomolecules and prebiotic dietary fiber. To valorize the leaf waste of the "Carciofo Ortano" landrace, a multidisciplinary approach was applied. Chemical analysis using HPLC-DAD identified mono-O- and di-O-caffeoylquinic acids and the sesquiterpene cynaropicrin in all artichoke leaf extracts. SPME-GC/MS analyses detected aliphatic alcohols in the fresh leaf samples. Antiproliferative and cytotoxic studies on cancer (SH-SY5Y, MCF-7, MDA) and normal (MCF-10A) human cell lines revealed that leaf extracts induced a selective dose and time-dependent biological effect. While showing slight activity against environmental bacterial strains, artichoke leaf extracts exhibited significant antifungal activity against the phytopathogenic fungus Alternaria alternata. Overall, the results highlight the potential of "Carciofo Ortano" cultivation by-products as a rich source of biomolecules with versatile applications in humans, animals, and the environment.

An Overview of the Versatility of the Parts of the Globe Artichoke (Cynara scolymus L.), Its By-Products and Dietary Supplements

Cynara scolymus, also known as the globe artichoke or artichoke, is grown as a food, mainly in the Mediterranean, Canary Islands, and Egypt, as well as in Asia and South America. It has also been associated with various health benefits and is used in plant-based dietary supplements and herbal infusions. Its edible parts, consisting of the head or capitula, flower, and leaves, have shown various biological activities, including anti-cancer, hepatoprotective and antimicrobial potential. The leaves are mainly used in infusions and extracts for their health-promoting properties, although all their edible parts may also be consumed as fresh, frozen, or canned foods. However, its primary health-promoting activity is associated with its antioxidant potential, which has been linked to its chemical composition, particularly its phenolic compounds (representing 96 mg of gallic acid equivalent per 100 g of raw plant material) and dietary fiber. The main phenolic compounds in the heads and leaves are caffeic acid derivatives, while the flavonoids luteolin and apigenin (both present as glucosides and rutinosides) have also been identified. In addition, heat-treated artichokes (i.e., boiled, steamed or fried), their extracts, and waste from artichoke processing also have antioxidant activity. The present paper reviews the current literature concerning the biological properties of different parts of C. scolymus, its by-products and dietary supplements, as well as their chemical content and toxicity. The literature was obtained by a search of PubMed/Medline, Google Scholar, Web of Knowledge, ScienceDirect, and Scopus, with extra papers being identified by manually reviewing the references.

Tragia plukenetii-Assisted Omega-Decenol as Potential Anticancer Agent: its Isolation, Characterization, and Validation

The second most common and lethal disease is lung cancer. To combat the negative effects of today's synthetic medications, natural phytomedicines are required. Tragia plukenetii is a medicinal plant native to India that belongs to the Euphorbiaceae family. The purpose of this research is to isolate bioactive compounds from T. plukenetii leaves and then test them for anticancer property. A single compound (CH: ME-20:80) was separated using TLC, and an RF value of 0.55 was determined. Spectral analyses utilizing UV-Visible Spectrophotometer and FT-IR were used to examine the absorbance and functional groups. ¹³C-NMR and ¹H-NMR studies revealed the tentative name of the purified phytochemical as omega-decenol (OD). Further antioxidant and anticancer properties of OD were tested for in vitro. In comparison to conventional L-ascorbic acid, the DPPH radical scavenging assay experiment yielded an IC₅₀ of 147.48 g/ml. With an IC₅₀ value of 24 µg/ml (Omega-decenol) and 32 µg/ml (doxorubicin), the MTT assay demonstrated the cytotoxic capability against the A549 lung cancer cell line. FACS revealed the cell cycle arrest of A549 at S phase compared to control with the high-dose IC₅₀ (250 µg/ml) of omega-decenol. Twelve major compounds were detected in the active fraction using GC-MS analysis, where n-hexadecanoic acid was found as a major. Omega-decenol showed good binding affinity against EGFR, amongst other receptors in the in silico docking study. This research reveals the potent anticancer activity of the isolated compound omega-decenol from T. plukenetii leaves and provides a key path to understanding the molecular interaction in anticancer aspects against adenocarcinoma.

Successive Solvent Extraction, Characterization and Antioxidant Activities of Cardoon Waste (Leaves and Stems) Extracts: Comparative Study

The main interest in the valorization of vegetable wastes is due to the peculiarity of their chemical composition in substances that present important properties. Among these substances, antioxidants could replace those industrially manufactured. In the present study, three solvents of different polarities (hexane, ethanol, and water) were applied for the extraction of phenolic compounds from Cynara cardunculus L. waste using two extraction methods: Soxhlet Extraction (SE) and Ultrasonic-Assisted Extraction (UAE). The obtained extracts were then characterized by Fourier-Transform Infrared (FTIR) spectroscopy and spectrophotometric determination of Total Phenolics (TPC), Total Flavonoids (TFC), and Condensed Tannins (CT). Total Antioxidant Capacity (TAC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity of ethanol and water extracts of leaves and stems were also evaluated. High extraction yields were obtained by UAE. Water extracts had high yield regardless of the technique used for leaves and stems, and these extracts showed high TAC of 534.72 ± 3.83 mg AAE/g FM for leaves and 215.70 ± 8.87 mg AAE/g FM (mg of ascorbic acid equivalent per g of FM) for stems, and IC₅₀ of 2077.491 μg/mL for leaves and 1248.185 μg/mL for stems. We explain the latter by the high total phenolic contents (TPCs), which reach 579.375 ± 3.662 mg GAE/g FM (mg of gallic acid equivalents per g of fresh matter) for leaves and 264.906 ± 3.500 mg GAE/g FM for stems. These results confirmed that the leaves and stems of the studied cardoon waste were, indeed, interesting sources of natural antioxidants.

Silver Nanoparticles Formulation of Flower Head’s Polyphenols of Cynara scolymus L.: A Promising Candidate against Prostate (PC-3) Cancer Cell Line through Apoptosis Activation

Cynara scolymus L. (Family: Compositae) or artichoke is a nutritious edible plant widely used for its hepatoprotective effect. Crude extracts of flower, bract, and stem were prepared and evaluated for their in vitro antioxidant activity and phenolic content. The flower crude extract exhibited the highest phenolic content (74.29 mg GAE/gm) as well as the best in vitro antioxidant activity using total antioxidant capacity (TAC), ferric reducing antioxidant power (FEAP), and 1,1-diphenyl-2-picrylhyazyl (DPPH) scavenging assays compared with ascorbic acid. Phenolic fractions of the crude extracts of different parts were separated and identified using high-performance liquid chromatography HPLC-DAD analysis. The silver nanoparticles of these phenolic fractions were established and tested for their cytotoxicity and apoptotic activity. Results showed that silver nanoparticles of a polyphenolic fraction of flower extract (Nano-TP/Flowers) exhibited potent cytotoxicity against prostate (PC-3) and lung (A549) cancer cell lines with IC₅₀ values of 0.85 μg/mL and 0.94 μg/mL, respectively, compared with doxorubicin as a standard. For apoptosis-induction, Nano-TP/Flowers exhibited apoptosis in PC-3 with a higher ratio than in A549 cells. It induced total prostate apoptotic cell death by 227-fold change while it induced apoptosis in A549 cells by 15.6-fold change. Nano-TP/Flowers upregulated both pro-apoptotic markers and downregulated the antiapoptotic genes using RT-PCR. Hence, this extract may serve as a promising source for anti-prostate cancer candidates.

Antioxidant and Anti-Inflammatory Effects of Extracts from Pulsed Electric Field-Treated Artichoke By-Products in Lipopolysaccharide-Stimulated Human THP-1 Macrophages

In this study, pulsed electric field (PEF—3 kV/cm; 5 kJ/kg) pretreatment was used to intensify the extractability of valuable intracellular compounds from artichoke by-products during a subsequent aqueous extraction (solid–liquid ratio = 1:10 g/mL, T = 20 °C; t = 120 min). Total phenolic content (TPC), antioxidant activity (DPPH, ABTS) and HPLC–PDA analysis of the artichoke extract (AE) and the biological effects on human cell lines were determined. Chlorogenic acid was found to be the most abundant phenolic compound (53% of the TPC) in the AE. The extract showed good antioxidant properties in a concentration-dependent manner. The potential biological effects of AE were investigated using THP-1 macrophages stimulated by lipopolysaccharides (LPS) as an in vitro model system of oxidative stress. Reduced reactive oxygen species production upon treatment with AE was found. Moreover, AE was able to reduce the secretion of the pro-inflammatory mediators Interleukin-6 and Monocyte Chemoattractant Protein-1 in LPS-stimulated macrophages, as determined by qRT-PCR and ELISA assays. These results highlighted the anti-inflammatory and antioxidant properties of the extracts from PEF-treated artichoke by-products, corroborating their potential application as a source of functional ingredients obtained through a feasible and sustainable process.

Phenolic Profiling and In-Vitro Bioactivities of Corn (Zea mays L.) Tassel Extracts by Combining Enzyme-Assisted Extraction

In this work, enzyme-assisted extraction (EAE) of phenolic compounds from corn tassel using cellulase, protease, and their combination (1:1) was developed and optimized by central composite response surface methodology. The phenolic profile of obtained corn tassel extracts (CTE) was elucidated by high-performance liquid chromatography−diode array detection (HPLC−DAD) analysis, and their antioxidative, antimicrobial, and cytotoxic properties were evaluated in vitro. The results showed that CTE by EAE with combined enzymes had the highest total phenolic content (TPC). Under optimum enzymatic conditions, the experimental TPC values were 9.78, 8.45, and 10.70 mg/g, respectively, which were significantly higher than that of the non-enzymatic control (6.75 mg/g) (p < 0.05). Fourteen more phenolic compounds (13.80−1694.36 µg/g) were identified in CTE by EAE with the combined enzymes, and thus the antioxidant activity of that extract, determined by DPPH and ABTS radical scavenging method, was demonstrated to be stronger than that of the extracts by EAE with the single and ethanol extraction. Furthermore, this extract also showed remarkably better antimicrobial properties against all tested food-borne pathogenic bacteria and mycotoxigenic fungi than CTE by other extraction methods. CTE by EAE were nontoxic to normal lung fibroblast cell line (Wi-38) but cytotoxic to human colorectal and lung cancer cell lines (Caco-2 and A549), with IC50 values of 392.62−461.98 and 210.66−359.56 µg/mL, respectively, which indicated its potential anticancer properties. In conclusion, CTE by EAE, especially with the combined use of cellulase and protease, seems to hold promising potential for multifunctional application in food and pharma fields.

Phenolic Composition and Antioxidant, Anti-Inflammatory, Cytotoxic, and Antimicrobial Activities of Cardoon Blades at Different Growth Stages

Simple Summary

The rapid increase of the world population has promoted a more sustainable and efficient use of natural resources. To achieve complete and proper upcycling of plant crops, it is important to know their potential for industrial exploitation. Cardoon (Cynara cardunculus L.) is a species native to the Mediterranean basin widely used in different sectors, including food and pharmaceuticals. Despite their multiple industrial applications, not all plant tissues have been incorporated into the value chain. Therefore, this work aimed to characterize the phenolic composition and bioactive properties of cardoon blades throughout the phenological growth cycle. In addition to the structural variety of phytochemicals detected in the blade extracts, their antioxidant, anti-inflammatory, anti-proliferative, and antimicrobial properties were also highlighted. While immature material showed higher levels of phenolic compounds and greater potential to inhibit lipid peroxidation, samples at higher development stages had greater anti-proliferative, anti-inflammatory, and antimicrobial potential. These results demonstrate that the growth cycle influences the bioactive potential of cardoon blades and will be useful to establish suitable industrial applications, such as the development of ingredients for functional foods and nutraceuticals, among other products.

Abstract

Cardoon (Cynara cardunculus var. altilis) blades were collected at sixteen sampling dates (B1–B16) to study the influence of the phenological growth stage on the phenolic composition and biological properties. Twenty phenolic compounds were identified, among which trans 3,4-O-dicaffeoylquinic acid, 5-O-caffeoylquinic acid, and luteolin-O-hexoside (39.6, 42.6, and 101.0 mg/g extract, respectively) were the main compounds. Immature blades (B3) had a higher content of phenolic compounds (178 mg/g extract) and a greater ability to inhibit the formation of thiobarbituric acid reactive substances (IC₅₀ of 1.61 µg/mL). Samples at more advanced growth stages revealed a greater capacity to inhibit oxidative hemolysis (B8, IC₅₀ of 25 and 47.4 µg/mL for Δt of 60 and 120 min, respectively) and higher cytotoxic (B8–B13, GI₅₀ between 7.1 and 17 µg/mL), anti-inflammatory (B13, IC₅₀ of 10 µg/mL), and antibacterial activities. In turn, the antifungal activity varied depending on the tested fungi. All these results suggest that maturity influences the phenolic composition and bioactive properties of cardoon blades, which reveal great potential for the development of bioactive ingredients for food and pharmaceutical applications, among others.

Development of gelatin/carboxymethylcellulose active films containing Hass avocado peel extract and their application as a packaging for the preservation of berries

This study aimed to evaluate the effect of incorporating different concentrations (0, 200, 300, and 400 mg L^-1) of avocado peel extracts (EE-AP) on the physicochemical properties and antifungal activity of gelatin-carboxymethylcellulose (Gel-CMC) films and their applicability in berry preservation. The results showed that incorporating EE-AP was compatible with the Gel-CMC film and enhanced the mechanical properties without affecting the integrity and thermal properties. The 200 mg L^-1 of EE-AP concentration on films offered the best barrier properties against water vapor (2.90 × 10^-11 g m^-1 s^-1 Pa^-1). FTIR identified the intramolecular and intermolecular interactions between the functional groups of biopolymers and the EE-AP. The results obtained revealed that EE-AP incorporation into gelatin-carboxymethylcellulose films significantly decreased the moisture content (from 12.48 to 11.02%) and solubility (from 40.13 to 35.39%) of the films. All films incorporated with EE-AP showed higher colorimetric parameters and opacity than the control film (p < 0.05). The DPPH radical scavenging ability of the Gel-CMC films was increased from 24.16 to 41.12, 57.21, and 63.47%, as the extract concentration increased. Active films presented excellent ultraviolet-visible light barrier properties. The antioxidant pigments (flavonoids and chlorophylls) were estimated spectrophotometrically through absorbance. In vitro tests indicated high effectiveness to inhibit the growth of Rhizopus stolonifer and Aspergillus niger. A preservation study indicated the absence of fungal development in berries over six days of storage. In conclusion, gelatin-carboxymethylcellulose films with EE-AP represent a potential option for active packaging and can preserve fresh fruit.

Bioactive Compounds from Cardoon as Health Promoters in Metabolic Disorders

Cardoon (Cynara cardunculus L.) is a Mediterranean plant and member of the Asteraceae family that includes three botanical taxa, the wild perennial cardoon (C. cardunculus L. var. sylvestris (Lamk) Fiori), globe artichoke (C. cardunculus L. var. scolymus L. Fiori), and domesticated cardoon (C. cardunculus L. var. altilis DC.). Cardoon has been widely used in the Mediterranean diet and folk medicine since ancient times. Today, cardoon is recognized as a plant with great industrial potential and is considered as a functional food, with important nutritional value, being an interesting source of bioactive compounds, such as phenolics, minerals, inulin, fiber, and sesquiterpene lactones. These bioactive compounds have been vastly described in the literature, exhibiting a wide range of beneficial effects, such as antimicrobial, anti-inflammatory, anticancer, antioxidant, lipid-lowering, cytotoxic, antidiabetic, antihemorrhoidal, cardiotonic, and choleretic activity. In this review, an overview of the cardoon nutritional and phytochemical composition, as well as its biological potential, is provided, highlighting the main therapeutic effects of the different parts of the cardoon plant on metabolic disorders, specifically associated with hepatoprotective, hypolipidemic, and antidiabetic activity.

Phenolic Composition and Biological Properties of Cynara cardunculus L. var. altilis Petioles: Influence of the Maturity Stage

Hydroethanolic extracts of cardoon petioles collected at sixteen growth stages (P1-P16) were characterized in terms of their phenolic composition and bioactive potential (antioxidant, cytotoxic, anti-inflammatory, and antimicrobial activities). Fifteen phenolic compounds were tentatively identified (i.e., ten phenolic acids and five flavonoid glycosides); the main compounds were 5-O-caffeoylquinic and 1,5-di-O-caffeoylquinic acids. Samples collected at early maturity (P1-P4) presented a weak positive correlation between the higher content in polyphenols (P3: 101-mg/g extract) and better inhibition capacity against thiobarbituric acid reactive substance formation (TBARS; P3: IC₅₀ = 5.0 µg/mL). Samples at intermediate maturation stages (P9) presented higher cytotoxic and anti-inflammatory potential. Moreover, immature petioles showed greater antihemolytic (OxHLIA; P4: IC₅₀ = 65 and 180 µg/mL for Δt of 60 and 120 min, respectively) and antibacterial activity. The antifungal activity varied depending on the maturation stage and the fungi strain. In conclusion, the maturation stage may greatly affect the polyphenols composition and content and the bioactive potential of cardoon petioles.

Artichoke By-Products as Natural Source of Phenolic Food Ingredient

Nowadays, the transformation activity of the food industry results in the generation of a huge amount of daily discarded vegetables wastes. One of those undervalued by-products are produced during the post-harvesting and processing process of artichokes. In the present research, the potential of artichokes’ bracts and stalks have been evaluated as a natural source of phenolic compounds which could be used as bioactive food ingredients, among others. In this study, the bioactive composition of those wastes has been evaluated using recent advances in extraction and analytical technologies, concretely, pressurized liquid extraction (PLE) followed by high-performance liquid chromatography (HPLC) coupled to electrospray time-of flight mass spectrometry (ESI-TOF/MS) analysis. To achieve this goal, first, the extraction process was evaluated by a comparative study using GRAS (Generally Recognized As Safe) solvents (mixtures of ethanol and water) at different temperatures (40–200 °C). The second step was to deeply characterize the composition of individual polyphenols by HPLC-ESI-TOF/MS in order to establish a comparison among the different PLE conditions applied to extract the phenolic fraction. The analysis revealed a wide variety of phenolic-composition, mainly phenolic acids and flavonoids. The results also highlighted that high percentages of ethanol and medium-high temperatures pointed out to be useful PLE conditions for recovering this kind of phytochemicals, which could be used in different applications, such as functional food ingredients, cosmetics, or nutraceuticals.