Search Results (32)

Arugula leaves (Diplotaxis tenuifolia L. and Eruca sativa L.) are a must-have ingredient in ready-to-eat salads, as they are prized for their appearance, taste, and flavor. The nutraceutical properties of this leafy vegetable are attributed to the presence of valuable secondary metabolites, such as phenolic acids and glucosinolates. Using UHPLC-Q-Orbitrap HRMS analysis and ion chromatography, we characterized the content of phenolic acids, glucosinolates, nitrates, and organic acids in organic arugula [Diplotaxis tenuifolia (L.) DC] and evaluated how the foliar application of three different non-microbial biostimulants (a seaweed extract, a vegetable protein hydrolysate, and a tropical plant extract) modulated the expression of these. Although the application of vegetable protein hydrolysate increased, compared to control plants, the nitrate content, the application of the same biostimulant increased the total content of glucosinolates and phenolic acid derivatives by 5.2 and 17.2%. Specifically, the foliar application of the plant-based biostimulant hydrolyzed protein significantly increased the content of glucoerucin (+22.9%), glucocheirolin (+76.8%), and ferulic acid (+94.1%). The highest values of flavonoid derivatives (173.03 μg g⁻¹ dw) were recorded from plants subjected to the exogenous application of seaweed extract. The results obtained underscore how biostimulants, depending on their origin and composition, can be exploited not only to improve agronomic performance but also to enhance the nutraceutical content of vegetables, guaranteeing end consumers a product with premium quality characteristics. Full article

The quest to establish permanent outposts in space, the Moon, and Mars requires growing plants for nutrition, water purification, and carbon/nutrient recycling, as well as the psychological well-being of crews and personnel on extra-terrestrial platforms/outposts. To achieve these essential goals, the safety, quality, and sustainability of plant material grown in space should be comparable to Earth-grown crops. In this study, radish plants were grown at 2500 ppm CO₂ in two successive grow-outs on the International Space Station and at similar CO₂ partial pressure at the Kennedy Space Center. An additional control experiment was performed at the University of Louisiana Lafayette laboratory, at ambient CO₂. Subsequent analyses of glucosinolate and sugar species and content showed that regardless of growth condition, glucoraphasatin, glucoraphenin, glucoerucin, glucobrassicin, 4-hydroxyglucobrassicin, 4-methoxyglucobrassicin, and three aliphatic GSLs tentatively assigned to 3-methylpentyl GSL, 4-methylpentyl GSL, and n-hexyl GSL were present in all examined plants. The most common sugars were fructose, glucose, and sucrose, but some plants also contained galactose, maltose, rhamnose, and trehalose. The variability of individual secondary metabolite abundances was not related to gravity conditions but appeared more sensitive to CO₂ concentration. No indication was found that radish cultivation in space resulted in stress(es) that increased glucosinolate secondary metabolism. Flavor and nutrient components in space-grown plants were comparable to cultivation on Earth. Full article

Several neurodegenerative diseases (NDDs), such as Huntington’s disease, six of the spinocerebellar ataxias, dentatorubral-pallidoluysian atrophy, and spinobulbar muscular atrophy, are caused by abnormally long polyglutamine (polyQ) tracts. Natural compounds capable of alleviating polyQ-induced toxicity are currently of great interest. In this work, we investigated the modulatory effect against polyQ neurotoxic aggregates exerted by erucin (ERN), an isothiocyanate naturally present in its precursor glucoerucin in rocket salad leaves and in its oxidized form, sulforaphane (SFN), in broccoli. Using C. elegans models expressing polyQ in different tissues, we demonstrated that ERN protects against polyQ-induced toxicity and that its action depends on the catalytic subunit of AMP-activated protein kinase (aak-2/AMPKα2) and, downstream in this pathway, on the daf-16/FOXO transcription factor, since nematodes deficient in aak-2/AMPKα2 and daf-16 did not respond to the treatment, respectively. Although triggered by a different source of neurotoxicity than polyQ diseases, i.e., by α-synuclein (α-syn) aggregates, Parkinson’s disease (PD) was also considered in our study. Our results showed that ERN reduces α-syn aggregates and slightly improves the motility of worms. Therefore, further preclinical studies in mouse models of protein aggregation are justified and could provide insights into testing whether ERN could be a potential neuroprotective compound in humans. Full article

Background/Objectives: Crude extracts from the Brassica genus have recently emerged as promising phytochemicals for preventing bone loss. While the most documented evidence suggests that their general biological activity is due to glucosinolates’ (GLSs’) hydrolysis products, the direct activity of GLSs is beginning to be uncovered. However, the contribution of GLSs to the bone-sparing activity of crude Brassicaceae extracts has seldom been addressed. Here, we aimed to gain insights into this gap by studying in the same in vitro model of human osteogenesis the effect of two Brassica seed extracts (Eruca sativa and Lepidium sativum) obtained from defatted seed meals, comparing them to the isolated GLSs most represented in their composition, glucoerucin (GER) and glucotropaeolin (GTL), for Eruca sativa and Lepidium sativum, respectively. Methods: Osteogenic differentiation of human mesenchymal stromal cells (hMSCs) was assessed by alizarin red staining assay and real-time PCR, respectively, evaluating mineral apposition and mRNA expression of specific osteogenic genes. Results: Both Brassica extracts and GLSs increased the osteogenic differentiation, indicating that the stimulating effect of Brassica extracts can be at least partially attributed to GLSs. Moreover, these data extend previous evidence of the effect of unhydrolyzed glucoraphanin (GRA) on osteogenesis to other types of GLSs: GER and GTL. Notably, E. sativa extract and GTL induced higher osteogenic stimulation than Lepidium sativum extract and GER, respectively. Conclusions: Overall, this study expands the knowledge on the possible application of Brassica-derived bioactive molecules as natural alternatives for the prevention and treatment of bone-loss pathologies. Full article

Arugula (Eruca sativa Mill.) is a nutritious vegetable, commonly used in salads, known for its high glucosinolate content and various health benefits and flavors. However, arugulas may contain -excessive nitrate levels, potentially harmful to human health. We aimed to examine the effect of substrate moisture levels on the growth and quality of arugula under controlled irrigation conditions to investigate a proper irrigation practice for the quality production of arugula. The plants were cultivated using a sensor-based automated irrigation system to maintain the substrate volumetric water content (VWC) levels at 0.20, 0.30, 0.40, and 0.50 m³·m⁻³ over three weeks (vegetative stage). The treatment with VWC of 0.20 m³·m⁻³ resulted in reduced shoot growth, primarily attributed to drought-induced constraints on leaf expansion. Despite the initial reductions in stomatal conductance in arugulas subjected to lower VWC treatments, they eventually recovered and exhibited similar stomatal conductance levels across all VWC treatments 15 days after treatment, indicating acclimation to drought stress. The VWC treatment did not affect the nitrate and total glucosinolate contents of arugula, except for a decrease in glucoerucin content observed in the lowest VWC treatment. Maintaining a VWC level at 0.20 m³·m⁻³ could impair both the growth and quality of arugula due to severe drought conditions. Alternatively, maintaining the VWC at 0.30 m³·m⁻³ would ensure a high water use efficiency while securing the growth and quality of arugula. Full article

This study aimed to analyse the chemical profile and biological activities of 29 accessions of Brassica rapa (turnips) and 9 of Brassica napus (turnips and seeds) collections, maintained ex situ in Portugal. HPLC-HRMS allowed the determination of glucosinolates (GLS) and polyphenolic compounds. The antioxidant and antimicrobial activities were determined by using relevant assays. The chemical profiles showed that glucosamine, gluconasturtiin, and neoglucobrassin were the most abundant GLS in the extracts from the turnip accessions. Minor forms of GLS include gluconapoleiferin, glucobrassicanapin, glucoerucin, glucobrassin, and 4-hydroxyglucobrassin. Both species exhibited strong antioxidant activity, attributed to glucosinolates and phenolic compounds. The methanol extracts of Brassica rapa accessions were assessed against a panel of five Gram-negative bacteria (Enterobacter cloacae, Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica subsp. enterica serovar, and Yersinia enterocolitica) and three Gram-positive bacteria (Bacillus cereus, Listeria monocytogenes, and Staphylococcus aureus). The extracts exhibited activity against S. enterica and S. aureus, and two showed inhibitory activity against E. coli and Y. enterocolitica. This study provides valuable insights into the chemical composition and biological properties of Brassica rapa and Brassica napus collections in Portugal. The selected accessions can constitute potential sources of natural antioxidants and bioactive compounds, which can be used in breeding programs and improving human health and to promote healthy food systems. Full article

Variations in the concentration of glucoraphanin (GRA) and glucoerucin (GER), as well as the corresponding breakdown products, isothiocyanates (ITCs) and nitriles, were investigated during the growth of broccoli sprouts. The concentrations of GRA and GER decreased sharply from 33.66 µmol/g to 11.48 µmol/g and 12.98 µmol/g to 8.23 µmol/g, respectively, after seed germination. From the third to the seventh day, both GRA and GER were maintained as relatively stable. The highest concentrations of sulforaphane (17.16 µmol/g) and erucin (12.26 µmol/g) were observed on the first day. Hereafter, the concentrations of nitrile hydrolyzed from GRA or GER were higher than those of the corresponding ITCs. Moreover, the ratio of sulforaphane to sulforaphane nitrile decreased from 1.35 to 0.164 from 1 d to 5 d, with a similar trend exhibited for erucin/erucin nitrile after 2 d. RNA-seq analysis showed that BolMYB28 and BolCYP83A1, involved in aliphatic glucosinolate (GSL) biosynthesis, remained largely unexpressed until the third day. In contrast, the genes operating within the GSL-myrosinase hydrolysis pathway were highly expressed right from the beginning, with their expression levels increasing significantly after the third day. Additionally, we identified two BolESPs and six BolNSPs that might play important roles in promoting the production of nitriles during the development of broccoli sprouts. Full article

Glucosinolates (GSLs) extracted from various parts of Iberis sempervirens L., including seeds, stems, leaves, and flowers, were qualitatively and quantitatively assessed. The analyses of GSLs were performed by their desulfo counterparts using the UHPLC-DAD-MS/MS technique and by their volatile breakdown products, isothiocyanates, using the GC-MS technique. The GSL profile comprised various types, including those derived from: methionine, represented by methylsulfinylalkyl GSL (glucoiberin), and methylsulfanylalkyl GSL (glucoibervirin and glucoerucin); phenylalanine (glucotropaeolin); and tryptophan (4-methoxyglucobrassicin). Among these, the highest level of glucoiberin was detected in the leaves, reaching 35.37 µmol/g of dry weight (DW), while the highest level of glucoibervirin was detected in the seeds, reaching 18.51 µmol/g DW. To obtain GSL breakdown products, a variety of isolation methods were employed, including hydrodistillation in a Clevenger-type apparatus (HD), CH₂Cl₂ after myrosinase hydrolysis for 24 h (EXT), microwave-assisted distillation (MAD), and microwave hydrodiffusion and gravity (MHG). Volatile isolates were tested for their antiproliferative activity using an MTT assay against the human lung cancer cell line A549 and the human bladder cancer cell line T24 during an incubation period of 72 h. HD and MAD showed the best activity against T24, with IC₅₀ values of 0.61 µg/mL and 0.62 µg/mL, respectively, while EXT was the most effective against the A549 cell line, with an IC₅₀ of 1.46 µg/mL. Full article

Glucosinolates are sulfur-containing phytochemicals generally abundant in cruciferous vegetables such as pak choy. Glucosinolates participate in a range of biological activities essential for promoting a healthy human body. In this study, we aimed to elucidate glucosinolate variability present in pak choy germplasm that are under conservation at the Rural Development Administration Genebank, Jeonju, Republic of Korea. The Acquity Ultra-Performance Liquid Chromatography (UHPLC) analytical system was used in profiling the glucosinolate content in leaf samples of various accessions. We identified a total of 17 glucosinolates in the germplasm. Based on principal compoment analysis performed, three separate groups of the accessions were obtained. Group 1 contained the cultivar cheongsacholong which recorded high content of glucobrassicin (an indole), glucoerucin (aliphatic), gluconasturtiin (aromatic) and glucoberteroin (aliphatic). Group 2 consisted of six accessions, BRA77/72, Lu ling gaogengbai, 9041, Wuyueman, RP-75 and DH-10, predominatly high in aliphatic compounds including glucoiberin, glucocheirolin, and sinigrin. Group 3 comprised the majority of the accessions which were characterized by high content of glucoraphanin, epiprogoitrin, progoitrin, and glucotropaeolin. These results revealed the presence of variability among the pak choy germplasm based on their glucosinolate content, providing an excellent opprtunity for future breeding for improved glucosinolate content in the crop. Full article

During the harvesting of the broccoli plant, the leaves are discarded, being considered a by-product that may be up to 47% of total broccoli biomass, representing a large amount of wasted material. The use of broccoli leaves is of great interest in the sense that this wasted material is rich in health promoter compounds, such as isothiocyanates. In this study, C57BL/6J mice ingested 790 mg/kg broccoli leaf flour, and the presence of glucosinolates and isothiocyanates in the plasma, liver, kidney, adipose tissue, faeces and urine was analysed at 1, 2, 4, 8, 12 and 24 h post-ingestion. In plasma, only glucoerucin (GE), glucobrassicin (GB), sulforaphane (SFN) and indol-3-carbinol (I3C) were detected, and all four compounds peaked between 4 and 8 h after ingestion. The compounds SFN, SFN-glutathione (SFN-GSH), SFN–cysteine (SFN-CYS) and SFN-N-acetyl-cysteine (SFN-NAC) were excreted in faeces at high levels, while glucoraphanin (GR), the precursor of SFN, was not detected in any biological samples other than urine. In the liver, the compounds GE, SFN-CYS, SFN-NAC and I3C were detected, while in the kidney, only GE, GB and SFN-GSH were present. None of the glucosinolates and isothiocyanates analysed were detected in fat tissue. These results demonstrate that glucosinolates and their derivatives were absorbed into the bloodstream and were bioavailable after ingestion of powdered broccoli leaves. Full article

Glucosinolates (GSLs) in different plant parts of broccoli (Brassica oleracea var. italic) and rocket (Eruca vesicaria) were analyzed qualitatively and quantitatively before and after treatment with sodium selenate (2 and 5 mM), by their desulfo-counterparts using the UHPLC-DAD-MS/MS technique. Twelve GSLs were detected in broccoli (five aliphatic, one arylaliphatic, and six indolic), where 4-(methylsulfanyl)butyl GSL (glucoerucin) was the main one in the roots (4.88–9.89 µmol/g DW), 4-(methylsulfinyl)butyl GSL (glucoraphanin) in stems (0.44–1.11 µmol/g DW), and 4-hydroxyindol-3-ylmethyl GSL (4-hydroxyglucobrassicin) in leaves (0.51–0.60 µmol/g DW). No GSL containing selenium was detected in the treated broccoli. Ten GSLs were detected in rocket (seven aliphatic and three indolic), where 4-(methylsulfanyl)butyl GSL (glucoerucin) was the main one in the roots (4.50–20.59 µmol/g DW) and 4-methoxyindol-3-ylmethyl GSL (4-methoxyglucobrassicin) in the aerial part (0.57–5.69 µmol/g DW). As a result of induced stress by selenium fertilization, the total GSL content generally increased in both plants. In contrast to broccoli, the roots and the aerial part of the rocket treated with a high concentration of sodium selenate contained 4-(methylseleno)butyl GSL (glucoselenoerucin) (0.36–4.48 µmol/g DW). Although methionine-derived GSLs are the most abundant in both plants, the plants’ ability to tolerate selenate and its regulation by selenoglucosinolate production is species- and growth-stage-dependent. Full article

In August 2020, the Eruca sativa cultivar “Rucola della Piana del Sele” obtained from the European Union the prestigious PGI (protected geographical indication) label, which certifies the uniqueness of its characteristics and increases its prestige both nationally and, above all, internationally. This plant is recognized as a product of excellence, with a unique flavor and unmistakable aroma. Therefore, since there are no methods to characterize the PGI product, a metabolomic approach was applied to characterize E. sativa grown in the Piana del Sele and different geographical areas. As E. sativa has very wide cultivation, this study sought to compare the metabolite profiles of rocket grown in Piana del Sele, Bergamo, and Brescia, as well as in Switzerland, making a comparison also with the metabolite profile of E. sativa grown spontaneously. To determine the best procedure to distinguish “Rucola della Piana del Sele” from the others, different extraction procedures were carried out using different solvents and fresh or freeze-dried plant matrices. The different extracts were analyzed by liquid chromatography coupled with high-resolution mass spectrometry experiments, using chemometric analyses to identify biomarker metabolites that characterize the PGI product. The LC-ESI-Q-Exactive-MS/MS profiles of methanol and hydroalcoholic extracts of different cultivars of E. sativa were found to be rich in bioactive compounds such as glucosinolates, glycosylated flavonoids, fatty acids, and lipids. The LCMS data were analyzed by principal component analysis (PCA); the score scatter plot shows significant separation among Eruca samples grown in different geographical areas. In detail, loading the scatter plot revealed Eruca grown in Piana del Sele to be richer than other cultivars in glycosylated quercetin 3,3′,4′-O-triglucoside (7), quercetin-3,4′-O-diglucoside-3′-O-(6-sinapoyl-glucoside) (10), and quercetin diglucoside (30). Finally, considering the biological interest in erucin, the myrosinase product of glucoerucin, the latter was quantified in the extracts by LC-ESI/QTrap/MS/MS using the multiple reaction monitoring (MRM) method; E. sativa from Piana del Sele showed the highest content of glucoerucin. Full article

Radish sprouts are valued as a key nutrient-dense food in Asian countries. In the current study, we examined how radish sprouts responded to treatments with various carbon sources. The influence of those treatments in parameters such as plant growth and glucosinolate and phenolic compounds levels were analyzed. A positive correlation between plant growth and the accumulation of glucosinolates and phenolics was observed. In this study, except for galactose treatment, all other carbon-exposed radish sprouts showed the highest shoot and root length and fresh weight. Seven different glucosinolate and five phenolic compounds were identified in radish sprouts. The total glucosinolates and phenolic compound content were increased after treatments with different carbon sources. Radish sprouts exposed to sucrose showed the highest total glucosinolates and phenolics content, which was 1.22-fold and 1.45-fold higher than that of untreated sprouts, respectively. Moreover, sucrose exposure led to a higher production of glucoiberin, gluconapoleiferin, 4-hydroxyglucobrassicin, glucoerucin, glucoraphasatin, glucobrassicin, gallic acid, sinapic acid, rutin, and p-coumaric acid compared to that of untreated sprouts. The results obtained in this study will be helpful for researchers around the world to enhance specific glucosinolate and phenolic compounds by treating the radish sprout plants with suitable carbon sources. Full article

Soil salinity can have various negative consequences on agricultural products, from their quality and production to their aesthetic traits. In this work, the possibility to use salt-affected vegetables, that otherwise would be discarded, as a source of nutraceuticals was explored. To this aim, rocket plants, a vegetable featuring bioactive compounds such as glucosinolates, were exposed to increasing NaCl concentrations in hydroponics and analysed for their content in bioactive compounds. Salt levels higher than 68 mM produced rocket plants that did not comply with European Union regulations and would therefore be considered a waste product. Anyway, our findings, obtained by Liquid Chromatography-High Resolution Mass Spectrometry, demonstrated a significant increase in glucosinolates levels in such salt-affected plants. opening the opportunity for a second life of these market discarded products to be recycled as glucosinolates source. Furthermore, an optimal situation was found at NaCl 34 mM in which not only were the aesthetic traits of rocket plants not affected, but also the plants revealed a significant enrichment in glucosinolates. This can be considered an advantageous situation in which the resulting vegetables still appealed to the market and showed improved nutraceutical aspects. Full article

Glucosinolates (GSLs) in Brassica oleracea L. convar. acephala var. viridis (collard) flower, leaf, stem, and root were analyzed qualitatively and quantitatively via their desulfo-counterparts using UHPLC-DAD-MS/MS. Twelve GSLs were identified, including Met-derived GSLs (sinigrin, glucoibervirin, glucoerucin, glucoiberin, glucoraphanin, progoitrin), Trp-derived GSLs (4-hydroxyglucobrassicin, glucobrassicin, 4-methoxyglucobrassicin, and neoglucobrassicin), and Phe-derived GSLs (glucotropaeolin and gluconasturtiin). Total GSL content was highest in the root, having 63.40 μmol/g dried weight (DW), with gluconasturtiin (34.02 μmol/g DW) as the major GSL, followed by sinigrin and glucoibervirin (12.43 and 7.65 μmol/g DW, respectively). Total GSL contents in the flower, leaf, and stem were lower than in root, having 6.27, 2.64, and 1.84 μmol/g DW, respectively, with Trp and/or Met-derived GSLs as the predominant ones. GSL breakdown products were obtained via microwave hydrodiffusion and gravity (MHG) and volatile breakdown products were analyzed using GC-MS techniques. Volatile isolates were tested for their cytotoxic activity using MTT assay. MHG volatile extract from the root demonstrated the best cytotoxic activity against human bladder cancer cell line T24 and breast cancer cell line MDA-MB-231 during an incubation time of 72 h (IC₅₀ 21.58, and 11.62 μg/mL, respectively). The activity of the root extract can be attributed to its major volatile, 2-phenylethyl isothiocyanate (gluconasturtiin breakdown product). Full article