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Suaeda salsa and Salicornia europaea are both annual herbaceous species belonging to the Chenopodiaceae family, and often grow together through our observations in the Yellow River Delta Nature Reserve, and could be used as raw material to produce food and beverages in food industry due to its high nutritional value. In this study, we adopted widely targeted metabolomics to identify 822 and 694 metabolites in the leaves of S. salsa and S. europaea, respectively, to provide a basic data for the future development and utilization of these two species. We found that these two plants were rich in metabolic components with high medical value, such as flavonoids, alkaloids and coumarins. The high contents of branched chain amino acid in these two species may be an important factor for their adaptation to saline-alkali environments. In addition, the contents of glucosamine (FC = 7.70), maltose (FC = 9.34) and D-(+)-sucrose (FC = 7.19) increased significantly, and the contents of D-(+)-glucose, 2-propenyl (sinigrin) and fructose 1-phosphate were significantly increased in the leaves of S. salsa compared to S. europaea, indicating that some certain compounds in different plants have different sensitivity to salt stress. Our work provides new perspectives about important second metabolism pathways in salt tolerance between these two plants, which could be helpful for studying the tolerance mechanisms of wetland plants.

The production of secondary defense chemicals in plants represents a trade-off between defense and the primary functions of growth and reproduction, but the relative allocation to growth versus defense varies across species, types of defenses, ontogeny, and environment. Alliaria petiolata (garlic mustard) is a brassica that produces glucosinolates, a class of constituent secondary metabolites that defend against herbivores and pathogens. Sinigrin, a hydrolyzed product of glucosinolate present in garlic mustard, may aid in its success as an invasive species by disrupting native plant–mycorrhizae mutualisms and decreasing forest species diversity in North America. Here, we measured sinigrin concentration in garlic mustard populations of different field densities and in greenhouse experiments to evaluate the relationship between sinigrin concentration and growth in response to density and varying environmental conditions. We found clear evidence for growth vs. defense tradeoffs in both experimental and field settings, as well as higher levels of defense in more densely growing, smaller individual plants. However, sinigrin levels and tradeoffs were not explained by soil fertility or light, allowing us to conclude that sinigrin expression is not controlled by limitations in the measured abiotic factors. Our findings suggest sinigrin leaf concentration increases at high densities despite the pressures of intraspecific competition that demand allocation to growth.

Stem mustard is a stem variety of mustard, an important Brassica vegetable. The formation and development of the tumorous stem, which is the key organ for the direct yield and quality, is a complex biological process involving morphogenesis, material accumulation and gene regulation. In this study, we demonstrated through anatomical studies that stem swelling is mainly dependent on the increase in the number of cells and the volume of parenchyma cells in the cortex and pith. To further understand transcript and metabolic changes during stem swelling, we obtained 27,901 differentially expressed genes, of which 671 were specifically detected using transcriptome sequencing technology in all four stages of stem swelling. Functional annotation identified enrichment for genes involved in photosynthesis, energy metabolism, cell growth, sulfur metabolism and glucosinolate biosynthesis. Glucosinolates are a group of nitrogen- and sulfur-containing secondary metabolites, which largely exist in the Cruciferous vegetables. HPLC analysis of the contents and components of glucosinolates in four different stem development stages revealed eight glucosinolates, namely, three aliphatic glucosinolates (sinigrin, glucoalyssin and gluconapin), four indole glucosinolates (4-hydroxyglucobrassicin, glucobrassicin, 4-methoxyglucobrassicin and neoglucobrassicin) and one aromatic glucosinolate (gluconasturtiin). All these types of glucosinolates showed a significant downward trend during the stem swelling period. The content of aliphatic glucosinolates was the highest, with sinigrin being the main component. In addition, qPCR was used to validate the expression of nine genes involved in glucosinolate biosynthesis. Most of these genes were down-regulated during stem swelling in qPCR, which is consistent with transcriptome data. These data provide a basic resource for further molecular and genetic research on Brassica juncea.

Glucosinolates (GSLs) are secondary metabolites produced by members of the genus Brassica. These compounds impart the pungency to brassica vegetables and oils. Due to their health benefits, which include anti-cancer and anti-fungal properties, they have been attracting interest in research. Indian mustard (B. juncea L.), used as condiment and oil crop has high natural levels of seed glucosinolates and displays exploitable natural variation in this trait. In this study a diverse collection of 161 mustard lines originating from 21 countries, will be genotyped and phenotyped. Traits of interest include seed GSLs (sinigrin, gluconapin, progroitin, epi-progoitin and glucoiberin), oil and protein content, as well as basic agro-morphological performance such as height, flowering time and yield. Current knowledge on GSL biosynthesis and its genetic regulation mostly relies on data from Arabidopsis thaliana. We aim to elucidate the genetic architecture of GSL content and composition in relation to other seed traits (oil and protein content) in our diversity panel through association mapping. Additionally, we are aiming to resolve genome complexity of GSL genes in mustard genome in contrast to A. thaliana by identifying gene copy number through in silico analysis. Outcome of this study will help streamline the breeding and product development for either high GSL mustard lines for condiment use or low GSL lines for canola-type oil use. Our preliminary data on seed GSLs seems to reflect the historical use of mustard in different geographical regions. Chinese and European lines featured higher GSL while lines from the Indian subcontinent displayed lower GSL contents.

Kale (Brassica oleracea L. Acephala Group) is the rich source of medicinal value sulphur compounds, glucosinolates (GLSs). The aim of this study was to investigate the effect of different proportion of sulphur (S) supplementation levels on the accumulation of GLSs in the leaves of the kale cultivar ('TBC'). High performance liquid chromatography (HPLC) separation method guided to identify and quantify six GSLs including three aliphatic (progoitrin, sinigrin and gluconapin) and three indolyl (glucobrassicin, 4-methoxyglucobrassicin and neoglucobrasscin) respectively. Analysis of these distinct levels of S supplementation revealed that the accumulation of individual and total GLSs was directly proportional to the S concentration. The maximum levels of total GLSs (26.8 µmol/g DW) and glucobrassicin (9.98 µmol/g DW) were found in lower and upper parts of the leaves supplemented with 1 mM and 2 mM S, respectively. Interestingly, aliphatic GSLs were noted predominant in all the parts (50.1, 59.3 and 56% of total GSLs). Among the aliphatic and indolyl GSLs, sinigrin and glucobrassicin account 35.3 and 30.88% of the total GSLs. From this study, it is concluded that supply of S enhance the GSLs accumulation in kale.

The present study aimed to investigate the contents of glucosinolates (GSLs) and carotenoids in eleven varieties of Chinese cabbage in relation to the expression level of the important transcription factors. MS and HPLC analysis identified the presence of 13 GSLs (progoitrin, sinigrin, glucoalyssin, gluconapoleiferin, gluconapin, glucocochlearin, glucobrassicanapin, glucoerucin, 4-hydroxyglucobrassicin, glucobrassicin, 4-methoxyglucobrassicin, neoglucobrassicin and gluconasturtiin) and four carotenoids (lutein, zeaxanthin, α-carotene and β-carotene). GSL contents were varied among the different cabbage varieties. The total GSL content ranged from 2.7 to 57.88μmol/gDW. The proportion of gluconapin (54%) and glucobrassicanapin (22%) was higher in all the varieties, respectively. Results documented the variation in total and individual carotenoid contents that have also been observed among different varieties; however, the total carotenoid contents ranged from 289.12 to 1001.41mgkg−1DW (mean 467.66). Interestingly, the proportion of lutein (66.5) and β-carotene (25.9) were higher than α-carotene (5.1) and zeaxanthin (2.5%). Consequently, the expression level of the regulatory gene, MYB28 was higher in ‘K0648’ and was directly proportional to GSL content. Similarly, the expression levels of 1-PSY were higher in ‘K0112’; however, the expression levels of 2-ZDS, 3-LCYB, 4-LCYE, 5-CHXB and 7-NCED genes showed no significant difference. In addition, the correlation between GSL and carotenoid contents and gene expression level showed moderate significant difference in each Chinese cabbage.

To glucosinolate (GSL) contents on flower buds depending on their position orders in turnip rape ( Brassica rapa ), three Japanese ‘Nabana’ cultivars such as cv. No. 21 ( Brassica rapa , early type), cv. Husanohana ( B. rapa , late type) and cv. Norin No. 20 ( B. napus ) were investigated using HPLC analysis. Ten GSLs including glucoraphanin, sinigrin, glucoalyssin, napoleiferin, gluconapin, 4-hydroxyglucobrassicin, glucobrassicanapin, glucobrassicin, and gluconasturtiin were detected. Differences in individual and total GSL contents were found between two plant varieties, which are also depending on various developmental stages. Among the GSLs, gluconapin (mean 23.11 μmole/g dry weight (DW) and glucobrassicanapin (mean 13.41 μmole/g DW) documented the most abundant compounds and contributed average 39 and 27% of the total GSLs, but indolyl and aromatic GSLs together accounted >10% of the total GSLs. The presence of significant quantities of gluconapin in the cultivars should be studied more extensively, since the GSL is mainly responsible for the bitter taste.

The cabbage moth, Mamestra brassicae L. (Lepidoptera: Noctuidae), is a generalist insect pest of cruciferous crops. We tested glucosinolate induction by jasmonic acid (JA) and salicylic acid (SA), and by these phytohormones combined with feeding by M. brassicae larvae in four genotypes of kale, Brassica oleracea L. var. acephala (Brassicaceae). The genotypes tested had high glucobrassicin (genotype HGBS), low glucobrassicin (genotype LGBS), high sinigrin (genotype HSIN), and low sinigrin content (genotype LSIN). Application of JA increased indolic and total glucosinolate content in all kale genotypes 1, 3, and 9 days after treatment. For SA-treated plants, glucosinolate induction varied depending on the number of days after treatment and the genotype. Overall, herbivory by M. brassicae accentuated and attenuated the effects of JA and SA, respectively, on plant glucosinolate content. Larvae of M. brassicae gained less weight on leaves from plants treated with JA compared to leaves from control plants and plants treated with SA. In bioassays with leaf discs, a significant reduction of defoliation only occurred in JA-treated plants of the HSIN genotype. This research shows that previous herbivory alters the susceptibility of kale to M. brassicae and that induction of glucosinolates varies among kale genotypes differing in their glucosinolate content.

Ongoing consumer concerns over using synthetic additives in foods has strongly influenced efforts worldwide to source suitable natural alternatives. In this study, the antibacterial efficacy of polyacetylene and glucosinolate compounds was evaluated against both Gram positive and Gram negative bacterial strains. Falcarinol [minimum inhibitory concentration (MIC) = 18.8-37.6 μg/mL] demonstrated the best overall antibacterial activity, while sinigrin (MIC = 46.9-62.5 μg/mL) was the most active glucosinolate compound. High-performance liquid chromatography with a diode array detector analysis showed falcarinol [85.13-244.85 μg/g of dry weight (DW)] to be the most abundant polyacetylene within six of the eight carrot (Daucus carota) cultivars investigated. Meanwhile, sinigrin (100.2-244.3 μg/g of DW) was the most abundant glucosinolate present within the majority of broccoli (Brassica oleracea) cultivars investigated using ultra performance liquid chromatography-tandem mass spectrometry analysis. The high abundance of both falcarinol and sinigrin within these respective species suggests that they could serve as potential sources of natural antibacterial agents for use as such in food products.

Differential accumulation of plant defence metabolites has been suggested to have important ecological consequence in the context of plant-insect interactions. Feeding of generalist pests on Brassica juncea showed a distinct pattern with selective exclusion of leaf margins which are high in glucosinolates. Molecular basis of this differential accumulation of glucosinolates could be explained based on differential expression profile of BjuMYB28 homologues, the major biosynthetic regulators of aliphatic glucosinolates, as evident from quantitative real-time PCR and promoter:GUS fusion studies in allotetraploid B. juncea. Constitutive overexpression of selected BjuMYB28 homologues enhanced accumulation of aliphatic glucosinolates in B. juncea. Performance of two generalist pests, Helicoverpa armigera and Spodoptera litura larvae, on transgenic B. juncea plants were poor compared to wild-type plants in a no-choice experiment. Correlation coefficient analysis suggested that weight gain of H. armigera larvae was negatively correlated with gluconapin (GNA) and glucobrassicanapin (GBN), whereas that of S. litura larvae was negatively correlated with GNA, GBN and sinigrin (SIN). Our study explains the significance and possible molecular basis of differential distribution of glucosinolates in B. juncea leaves and shows the potential of overexpressing BjuMYB28 for enhanced resistance of Brassica crops against the tested generalist pests.

Glucosinolates are the most abundant secondary sulfur-containing plant metabolites in the plant family of Brassicaceae. These phytochemicals are well-known for their enzymatic degradation induced by the enzyme myrosinase, resulting in pungent odor impressions derived from their respective degradation products. However, up to now, only little attention has been paid to non-enzymatic thermal degradation and the release of additional aroma-active compounds. Thermal treatment is particularly important in the processing of Brassica vegetables, and thereby, glucosinolates as precursors can act as a natural source of odorants. Application of gas chromatography-olfactometry to the volatile fractions obtained after heat treatment of sinigrin (2-propenyl glucosinolate) in different matrices (phosphate buffer at a pH value of 5, 7, or 9, silicon oil, silica gel (7% water), sea sand, and glycerol) showed a high potential to generate aroma-active compounds, mainly revealing onion- and garlic-like odor impressions deriving from sulfur-containing odorants. A clear dependency of the formation of desired aroma-active compounds upon the respective matrix was found, indicating the need of detailed investigations to obtain knowledge for the best use of glucosinolates as a source of natural aroma compositions. For example, the distillate obtained from sinigrin heat-processed in buffer solution at pH 7 led to the identification of 17 odorants.

Environmental stress hinders growth of plants and commonly results in the accumulation of carbon-based defense compounds. However, the dynamics of nitrogen (N)-containing defense compounds are less predictable under environmental stress. The impact of nutrient deficiency on plant defenses that require the metabolic conversion of a less toxic compound to a more potent toxin is even more poorly understood. We evaluated the effects of nitrogen (N) and potassium (K) deficiency and simulated herbivory on the concentration of metabolites including glucosinolates (GSLs), on the conversion of GSLs to more toxic isothiocyanates (ITCs), and on the activity of myrosinase (MYR) in leaves of Brassica juncea and Brassica nigra. Both species contained GSLs, predominantly sinigrin, but also derivatives of glucobrassicin. Compared to the control, N deficiency increased the sinigrin concentration in both species. Methyl jasmonate (MeJA) application increased sinigrin production in B. junceae, whereas in B. nigra MeJA increased sinigrin only under K-deficiency. Compared to the aliphatic-glucosinolates, MeJA application produced a greater compositional change in the profiles of indolic-glucosinolates. In both species the increase in sinigrin content of the tissue was associated with a decrease in its overall nutritive value as assessed by the content of sugars and amino acids. In B. juncea, application of MeJA decreased the conversion of sinigrin to allyl isothiocyanate (AITC) under both N and K deficiency. The potential activity of MYR decreased in both species under N deficiency. The reduced conversion of sinigrin to AITC and the lower activity of MYR suggest that the GSL-ITC defense system might have a limited efficiency in deterring generalist herbivores under environmental stress.

Introduction The oxylipin methyl jasmonate (MeJA) is a plant hormone active in response signalling and defence against herbivores. Although MeJA is applied experimentally to mimic herbivory and induce plant defences, its downstream effects on the plant metabolome are largely uncharacterized, especially in the context of primary growth and tissue-specificity of the response. Objectives We investigated the effects of MeJA-simulated and real caterpillar herbivory on the foliar metabolome of the wild plant Brassica nigra and monitored the herbivore-induced responses in relation to leaf ontogeny. Methods As single or multiple herbivory treatments, MeJA- and mock-sprayed plants were consecutively exposed to caterpillars or left untreated. Gas chromatography (GC) and liquid chromatography (LC) time-of-flight mass-spectrometry (TOF-MS) were combined to analyse foliar compounds, including central primary and specialized defensive plant metabolites. Results Plant responses were stronger in young leaves, which simultaneously induced higher chlorophyll levels. Both MeJA and caterpillar herbivory induced similar, but not identical, accumulation of tricarboxylic acids (TCAs), glucosinolates (GSLs) and phenylpropanoids (PPs), but only caterpillar feeding led to depletion of amino acids. MeJA followed by caterpillars caused higher induction of defence compounds, including a three-fold increase in the major defence compound allyl-GSL (sinigrin). When feeding on MeJA-treated plants, caterpillars gained less weight indicative of the reduced host-plant quality and enhanced resistance. Conclusions The metabolomics approach showed that plant responses induced by herbivory extend beyond the regulation of defence metabolism and are tightly modulated throughout leaf development. This leads to a new understanding of the plant metabolic potential that can be exploited for future plant protection strategies.

Plutella xylostella L. is a notorious pest of cruciferous crops causing worldwide losses of $4-5 billion per year. Developing classical biological control to this pest include an introduction of host plants that act as natural enemies showing deviation from the preference-performance regimen in the evolutionary ecology of plant-insect interactions. The present study was designed to understand the role of glucosinolate-myrosinase system during P. xylostella interactions with a novel host. Adult moth preference and larval performance study were conducted on a novel host Lepidium latifolium L. (LL) that has high sinigrin content and was compared with its laboratory host Arabidopsis thaliana (AT). The glucosinolate-myrosinase system was studied in a time course experiment during larval feeding in choice and no-choice experiments. Adult moths visit and prefers LL over AT for oviposition. Conversely, LL leaves were not preferred and proved detrimental for P. xylostella larvae. Aliphatic and indolic glucosinolates were found to decrease significantly (p≤0.05) in AT during initial 12h of P. xylostella challenge, whereas, they were not affected in LL. Also, MYB transcription factor expression and myrosinase activity in LL do not suggest a typical host response to a specialist insect. This preference-performance mismatch of P. xylostella on LL mediated by glucosinolate pattern suggests that this novel plant could be utilized in P. xylostella management.

The glucosinolate profiles, phenol and flavonoid contents and the antioxidant activity of Eruca vesicaria longirostris were studied for different organs and origins. Eleven desulpho-glucosinolates (DS-GLSs) were isolated and quantified by lipid chromatography- DAD. Similarity between profiles was obtained. Total DS-GLS content, expressed as sinigrin equivalents (SE) revealed a certain variabilily ranging between (76.07-45.61), (27.01-13.53), (4.52 -18.01), (9.39-3.37) and (1.16-13.99) µmol /g DW for seeds, flowers, leaves, roots and stems, respectively. Results showed that seeds are rich in phenolics as they contain highest amounts of phenolics ranging from 27.6±0.5 to 33.47±0.5 mg GAE/g extract as compared to all other parts. Leaves and flowers had a significantly higher total phenolic content than stems and roots in all samples (p < 0.05). According to statistical analysis, the investigated seed extracts with values between (16.20±0.10-18.50±0.10 mg QE/g) exhibited the highest total flavonoids content, followed by leaves (13.00±0.40-15.80±0.30mg QE/g), flowers (10.40±0.40-12.90±0.90 mg QE/g) and stems (7.80±0.20- 9.80±0.70 mg QE/g). Antioxidant activity tested by DPPH, ABTS and FRAP assays, was higher for seeds, leaves and flowers than the other studied organs. These organs were characterized by a significantly high content in glucoerucin, nasturtin and epiprogroitrin, respectively.

Spodoptera litura is polyphagous pest insect and feeds on plants of more than 90 families. In this study the role of glutathione S-transferase epilson 1 (slgste1) in S. litura in detoxification was examined. This gene was up-regulated in the midgut of S. litura at the transcriptional and protein levels when the insect fed on Brassica juncea or diet containing phytochemicals such as indole-3-carbinol and allyl-isothiocyanate that are metabolic products of sinigrin and glucobrassicin in B. juncea. The SlGSTE1 could catalyze the conjugation of reduced glutathione and indole-3-carbinol and allyl-isothiocyanate, as well as xanthotoxin, which is a furanocoumarin, under in vitro condition. When the expression of Slgste1 in the larvae was suppressed with RNAi, the larval growth and feeding rate were decreased. Furthermore, the up-regulated expression of the SlGSTE1 protein in the midgut of larvae that fed on different host plants was detected by 2-DE and ESI/MS analysis. The feeding adaptation from the most to the least of the larvae for the various host plants was Brassica alboglabra, Brassica linn. Pekinensis, Cucumis sativus, Ipomoea batatas, Arachis hypogaea and Capsicum frutescens. All the results together suggest that Slgste1 is a critical detoxifying enzyme that is induced by phytochmicals in the host plants and, inter alia, may be related to host plant adaptation of S. litura.

The joint toxicity of chlorantraniliprole, a novel insecticide that acts on ryanodine receptors, and sinigrin, a natural plant defense compound from brassicaceous vegetables, to the larvae of Spodoptera exigua (Hübner) was determined in this paper. Additionally, the joint effects of the two compounds on cytochrome P450 enzyme activity and on the expression levels of mRNA of three P450 genes (including CYP9A9, CYP6B, and CYP4G37) and an NADPH cytochrome P450 reductase gene (HQ852049) were investigated. The toxicity of the mixture of chlorantraniliprole and sinigrin to fourth-instar S. exigua larvae was 1.60-fold higher than the toxicity of the chlorantraniliprole-only treatment after 24 h. Induced by chlorantraniliprole and sinigrin, the specific activity of the P450 O-deethylase was affected in a time-, dose-, and organ-specific manner in fifth-instar S. exigua larvae. The effects were more pronounced in the midgut than in the fat body. The specific activity of the P450 O-deethylase in almost all treatments increased at 12, 24, and 36 h posttreatment compared with that in the control. Based on real-time PCR analyses, the expression levels of the P450 genes CYP9A9, CYP6B, and CYP4G37 and the NADPH cytochrome P450 reductase gene HQ852049 in fifth-instar S. exigua larvae were induced by chlorantraniliprole and sinigrin, and the trends were similar to the specific activity of the P450 O-deethylase. Therefore, the CYP9A9, CYP6B, and HQ852049 in the tested genes were the most inducible genes that were expressed when the S. exigua larvae were exposed to chlorantraniliprole and sinigrin.

In some plant-insect interactions, specialist herbivores exploit the chemical defenses of their food plant to their own advantage. Brassica plants produce glucosinolates that are broken down into defensive toxins when tissue is damaged, but the specialist aphid, Brevicoryne brassicae, uses these chemicals against its own natural enemies by becoming a "walking mustard-oil bomb". Analysis of glucosinolate concentrations in plant tissue and associated aphid colonies reveals that not only do aphids sequester glucosinolates, but they do so selectively. Aphids specifically accumulate sinigrin to high concentrations while preferentially excreting a structurally similar glucosinolate, progoitrin. Surveys of aphid infestation in wild populations of Brassica oleracea show that this pattern of sequestration and excretion maps onto host plant use. The probability of aphid infestation decreases with increasing concentrations of progoitrin in plants. Brassica brassicae, therefore, appear to select among food plants according to plant secondary metabolite profiles, and selectively store only some compounds that are used against their own enemies. The results demonstrate chemical and behavioral mechanisms that help to explain evidence of geographic patterns and evolutionary dynamics in Brassica-aphid interactions.

The glucosinolates content of brassica plants is a distinctive characteristic, representing a healthy advan- tage as many of these compounds are associated to antioxidant and anti-carcinogenic properties. Brassica sprouts are still an underutilized source of these bioactive compounds. In this work, four varieties of bras- sica sprouts (red cabbage, broccoli, Galega kale and Penca cabbage), including two local varieties from the North of Portugal, were grown to evaluate the glucosinolate profile and myrosinase activity during the sprouting. Also the influence of light/darkness exposure during sprouting on the glucosinolate content was assessed. Glucosinolate content and myrosinase activity of the sprouts was evaluated by HPLC meth- ods. All sprouts revealed a higher content of aliphatic glucosinolates than of indole glucosinolates, con- trary to the profile described for most of brassica mature plants. Galega kale sprouts had the highest glucosinolate content, mainly sinigrin and glucoiberin, which are recognized for their beneficial health effects. Penca cabbage sprouts were particularly richer in glucoraphanin, who was also one of the major compounds in broccoli sprouts. Red cabbage showed a higher content of progoitrin. Regarding myrosi- nase activity, Galega kale sprouts showed the highest values, revealing that the use of light/dark cycles and a sprouting phase of 7?9 days could be beneficial to preserve the glucosinolate content of this variety. B514-8F2F-A1FB | Ana Vale N/A

The antifungal properties of isothiocyanates released from the hydrolysis of the glucosinolate sinigrin were assessed on an Armillaria mellea strain in Petri dishes. The fumigation with sinigrin at 100 µM showed a fungicidal effect, while lower rates determined a temporary fungistatic effect. The application of increasing rates of solid and liquid biofumigant formulations on A. mellea inoculated potted peach plants showed an increase of soil nitrate concentration, basal respiration, microbial biomass, leaf nitrogen and chlorophyll concentration. These effects indicated a stimulating effect of Brassicaceae derivatives on soil biological activity and plant growth. The application of a rate of meal higher than 6.42 g kg−1 soil caused a stunted growth and the death of some plants showing a clear phytotoxic effect of the treatments. The inhibition of A. mellea growth observed in in vitro trials was not evidenced in in vivo experiments due to the lack of infection symptoms in experimentally inoculated potted trees.

The identification of genetic factors influencing the accumulation of individual glucosinolates in broccoli florets provides novel insight into the regulation of glucosinolate levels in Brassica vegetables and will accelerate the development of vegetables with glucosinolate profiles tailored to promote human health. Quantitative trait loci analysis of glucosinolate (GSL) variability was conducted with a B. oleracea (broccoli) mapping population, saturated with single nucleotide polymorphism markers from a high-density array designed for rapeseed (Brassica napus). In 4 years of analysis, 14 QTLs were associated with the accumulation of aliphatic, indolic, or aromatic GSLs in floret tissue. The accumulation of 3-carbon aliphatic GSLs (2-propenyl and 3-methylsulfinylpropyl) was primarily associated with a single QTL on C05, but common regulation of 4-carbon aliphatic GSLs was not observed. A single locus on C09, associated with up to 40 % of the phenotypic variability of 2-hydroxy-3-butenyl GSL over multiple years, was not associated with the variability of precursor compounds. Similarly, QTLs on C02, C04, and C09 were associated with 4-methylsulfinylbutyl GSL concentration over multiple years but were not significantly associated with downstream compounds. Genome-specific SNP markers were used to identify candidate genes that co-localized to marker intervals and previously sequenced Brassica oleracea BAC clones containing known GSL genes (GSL-ALK, GSL-PRO, and GSL-ELONG) were aligned to the genomic sequence, providing support that at least three of our 14 QTLs likely correspond to previously identified GSL loci. The results demonstrate that previously identified loci do not fully explain GSL variation in broccoli. The identification of additional genetic factors influencing the accumulation of GSL in broccoli florets provides novel insight into the regulation of GSL levels in Brassicaceae and will accelerate development of vegetables with modified or enhanced GSL profiles.

Glucosinolates may deter generalist insect feeding as their toxicity causes fitness damage, whereas insects specialized in brassicaceous plants may circumvent the toxic effect. By using no-choice leaf tests, we investigated whether larval development time, body weight, mortality and feeding rate of the generalist Mamestra brassicae (Lepidoptera, Noctuidae) and the specialist Pieris rapae (Lepidoptera, Pieridae), were affected by six genotypes of Brassica oleracea var. acephala, selected for having high or low concentration of sinigrin, glucoiberin (aliphatics) and glucobrassicin (indole). Two phenological plant stages were used. On young plants, M. brassicae most consumed the high sinigrin and low glucoiberin genotypes. Larvae weighed more on the high sinigrin plants. Development time took longer on the low glucoiberin genotype. On mature plants, consumption rate decreased on the high glucoiberin genotype. Larval weight decreased on the high sinigrin, glucoiberin and glucobrassicin genotypes, and development time increased with high glucobrassicin concentration. Pupal weight and mortality rate increased on mature plants, irrespective of the genotype. Pieris rapae fed most on young plants with high sinigrin, and larval weight increased on the high glucoiberin genotype. Mortality increased with low glucoiberin and low glucobrassicin. On mature plants, larval weight decreased with high sinigrin and glucoiberin. The high glucoiberin genotype was the less consumed and also induced a longer development time. High content of aliphatic glucosinolates offered mature plants significant antibiosis defence against both the lepidopterans, whereas the indole glucosinolate was marginally effective. Young plants were more consumed and increased larval weight likely because glucosinolate concentration was still not optimal.

Horseradish (Armoracia rusticana) is a perennial crop and its ground root tissue is used in condiments because of the pungency of the glucosinolate (GS)-hydrolysis products allyl isothiocyanate (AITC) and phenethyl isothiocyanate (PEITC) derived from sinigrin and gluconasturtiin, respectively. Horseradish roots are sold in three grades: U.S. Fancy, U.S. No. 1, and U.S. No. 2 according to the USDA standards. These grading standards are primarily based on root diameter and length. There is little information on whether root grades vary in their phytochemical content or potential health promoting properties. This study measured GS, GS-hydrolysis products, potential anticancer activity (as quinone reductase inducing activity), total phenolic content, and antioxidant activities from different grades of horseradish accessions. U.S. Fancy showed significantly higher sinigrin and AITC concentrations than U.S. No. 1 ,whereas U.S. No. 1 showed significantly higher concentrations of 1-cyano 2,3-epithiopropane, the epithionitrile hydrolysis product of sinigrin, and significantly higher total phenolic concentrations than U.S. Fancy.

Cauliflower ( Brassica oleraceae L. var. Botrytis ) is a good source of bioactive compounds, such as glucosinolates, phenolic compounds and vitamins. In this study, the effects of some processes ( i.e. boiling, steaming) on the sinigrin bioaccessibility as a major glucosinolate found in cruciferous vegetables after in vitro digestion, also in vitro antimutagenic activities, total phenols and total antioxidant capacities of cauliflower were determined. The sinigrin content was reduced by approximately 9.6% and 29.1% in steamed and boiled cauliflower ( p > 0.05), respectively. After in vitro simulated digestion, sinigrin content was decreased by 26.4% in raw samples, increased by 29.5% and 114.7% in steamed and boiled samples, respectively. In all samples, mutagenic effect to Salmonella typhimurium TA 100 was not seen. When samples were steamed, phenol content was increased by 14.83%. After boiling total phenol content of cauliflower was decreased by 1.8%. Total antioxidant capacities (TAC) measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3 ethylbenzothiazoline-6-sulfonic acid) (ABTS) methods were increased by 47% and 39%, respectively ( p p > 0.05). TAC in raw sample of cauliflower, which was investigated in phosphomolybdenum assays, was determined as 18.7 mg ascorbic acid equivalents (AAE)/100 g. In all cases, the highest antioxidant activity was determined in the steamed samples, while the lowest antioxidant activity was in boiled samples.

Glucosinolates (GSLs) are secondary metabolites found in Brassica vegetables that confer on them resistance against pests and diseases. Both GSLs and glucosinolate hydrolysis products (GHPs) have shown positive effects in reducing soil pathogens. Information about their in vitro biocide effects is scarce, but previous studies have shown sinigrin GSLs and their associated allyl isothiocyanate (AITC) to be soil biocides. The objective of this work was to evaluate the biocide effects of 17 GSLs and GHPs and of leaf methanolic extracts of different GSL-enriched Brassica crops on suppressing in vitro growth of two bacterial (Xanthomonas campestris pv. campestris and Pseudomonas syringae pv. maculicola) and two fungal (Alternaria brassicae and Sclerotinia scletoriorum) Brassica pathogens. GSLs, GHPs, and methanolic leaf extracts inhibited the development of the pathogens tested compared to the control, and the effect was dose dependent. Furthermore, the biocide effects of the different compounds studied were dependent on the species and race of the pathogen. These results indicate that GSLs and their GHPs, as well as extracts of different Brassica species, have potential to inhibit pathogen growth and offer new opportunities to study the use of Brassica crops in biofumigation for the control of multiple diseases.

The aim of this study was to assess the feasibility of controlling the potato cyst nematode Globodera pallida through biofumigation with glucosinolate-rich Brassica juncea genotypes. The main glucosinolate of B. juncea is 2-propenyl glucosinolate which is the precursor of 2-propenyl isothiocyanate. Toxicity of 2-propenyl isothiocyanate to encysted G. pallida was tested in vitro . Fifty percent reduction in hatching was found within 2 h of exposure to 0.002% 2-propenyl isothiocyanate. Based on the in vitro results, we hypothesized that biofumigation with B. juncea would reduce hatching of G. pallida in vivo and higher 2-propenyl glucosinolate levels would have a stronger effect. Plant genotype, sulfur fertilization and insect herbivory affected 2-propenyl glucosinolate concentration of B. juncea . However, increasing 2-propenyl glucosinolate concentration of B. juncea did not affect G. pallida hatching after biofumigation. The absence of a biofumigation effect was most likely due to lower concentrations of 2-propenyl isothiocyanate in vivo compared to in vitro conditions. These results show that it is difficult to reach sufficiently high levels of toxicity to reduce hatching of G. pallida under realistic conditions.

Mustard is a Brassica vegetable that provides a number of phytonutrients. However, the phytonutrient profile of mustard has been relatively limited. We analyzed the glucosinolates and their hydrolysis products, carotenoids, total anthocyanin and phenolic contents, and antioxidant capacity of the leaves of 11 mustard cultivars grown in a greenhouse at the baby leaf and mature stages. An aliphatic glucosinolate sinigrin and its hydrolysis products allyl isothiocyanate and 1-cyano-2,3-epithiopropane were the major phytonutrients in the mustard leaves. Carotenoids β-carotene, lutein, violaxanthin, and neoxanthin were detected. We found phytonutrient concentration and their change with plant growth were cultivar-dependent. The %RDA value for vitamin A calculated using β-carotene content and retinol activity equivalents suggests that mustard cultivars used in this study can be a good source of vitamin A. Phenolic contents and antioxidant capacity also varied among cultivars and between physiological stages. Our results suggest that mustard leaves are rich in various phytochemicals and their composition depends on cultivar and the physiological stage. This is the first report on phytochemical composition in various mustard cultivars at different physiological stages.

Drought can severely damage crops, resulting in major yield losses. During drought, vascular land plants conserve water via stomatal closure. Each stomate is bordered by a pair of guard cells that shrink in response to drought and the associated hormone abscisic acid (ABA). The activation of complex intracellular signaling networks underlies these responses. Therefore, analysis of guard cell metabolites is fundamental for elucidation of guard cell signaling pathways. Brassica napus is an important oilseed crop for human consumption and biodiesel production. Here, non-targeted metabolomics utilizing gas chromatography mass spectrometry (GC-MS/MS) and liquid chromatography mass spectrometry (LC-MS/MS) were employed for the first time to identify metabolic signatures in response to ABA in B. napus guard cell protoplasts. Metabolome profiling identified 390 distinct metabolites in B. napus guard cells, falling into diverse classes. Of these, 77 metabolites, comprising both primary and secondary metabolites were found to be significantly ABA responsive, including carbohydrates, fatty acids, glucosinolates, and flavonoids. Selected secondary metabolites, sinigrin, quercetin, campesterol, and sitosterol, were confirmed to regulate stomatal closure in Arabidopsis thaliana, B. napus or both species. Information derived from metabolite datasets can provide a blueprint for improvement of water use efficiency and drought tolerance in crops.

Vegetables of the Brassica oleracea group, such as broccoli, cauliflower, and cabbage, play an important role for glucosinolate consumption in the human diet. Upon maceration of the vegetable tissue, glucosinolates are degraded enzymatically to form volatile isothiocyanates, nitriles, and epithionitriles. However, only the uptake of isothiocyanates is linked to the cancer-preventive effects. Thus, it is of great interest to evaluate especially the isothiocyanate formation. Here, we studied the formation of glucosinolates and their respective hydrolysis products in sprouts and fully developed vegetable heads of different genotypes of the five B. oleracea varieties: broccoli, cauliflower as well as white, red, and savoy cabbages. Further, the effect of ontogeny (developmental stages) during the head development on the formation of glucosinolates and their respective hydrolysis products was evaluated at three different developmental stages (mini, fully developed, and over-mature head). Broccoli and red cabbage were mainly rich in 4-(methylsulfinyl)butyl glucosinolate (glucoraphanin), whereas cauliflower, savoy cabbage and white cabbage contained mainly 2-propenyl (sinigrin) and 3-(methylsulfinyl)propyl glucosinolate (glucoiberin). Upon hydrolysis, epithionitriles or nitriles were often observed to be the main hydrolysis products, with 1-cyano-2,3-epithiopropane being most abundant with up to 5.7 μmol/g fresh weight in white cabbage sprouts. Notably, sprouts often contained more than 10 times more glucosinolates or their hydrolysis products compared to fully developed vegetables. Moreover, during head development, both glucosinolate concentrations as well as hydrolysis product concentrations changed and mini heads contained the highest isothiocyanate concentrations. Thus, from a cancer-preventive point of view, consumption of mini heads of the B. oleracea varieties is recommended.

Background Glucosinolates, anionic sulfur rich secondary metabolites, have been extensively studied because of their occurrence in the agriculturally important brassicaceae and their impact on human and animal health. There is also increasing interest in the biofumigant properties of toxic glucosinolate hydrolysis products as a method to control agricultural pests. Evaluating biofumigation potential requires rapid and accurate quantification of glucosinolates, but current commonly used methods of extraction prior to analysis involve a number of time consuming and hazardous steps; this study aimed to develop an improved method for glucosinolate extraction. Results Three methods previously used to extract glucosinolates from brassicaceae tissues, namely extraction in cold methanol, extraction in boiling methanol, and extraction in boiling water were compared across tissue type (root, stem leaf) and four brassicaceae species (B. juncea, S. alba, R. sativus, and E. sativa). Cold methanol extraction was shown to perform as well or better than all other tested methods for extraction of glucosinolates with the exception of glucoraphasatin in R. sativus shoots. It was also demonstrated that lyophilisation methods, routinely used during extraction to allow tissue disruption, can reduce final glucosinolate concentrations and that extracting from frozen wet tissue samples in cold 80% methanol is more effective. Conclusions We present a simplified method for extracting glucosinolates from plant tissues which does not require the use of a freeze drier or boiling methanol, and is therefore less hazardous, and more time and cost effective. The presented method has been shown to have comparable or improved glucosinolate extraction efficiency relative to the commonly used ISO method for major glucosinolates in the Brassicaceae species studied: sinigrin and gluconasturtiin in B. juncea; sinalbin, glucotropaeolin, and gluconasturtiin in S. alba; glucoraphenin and glucoraphasatin in R. sativus; and glucosatavin, glucoerucin and glucoraphanin in E. sativa. Electronic supplementary material The online version of this article (doi:10.1186/s13007-017-0164-8) contains supplementary material, which is available to authorized users.

Glucosinolates are a well-studied and highly diverse class of natural plant compounds. They play important roles in plant resistance, rapeseed oil quality, food flavoring, and human health. The biological activity of glucosinolates is released upon tissue damage, when they are mixed with the enzyme myrosinase. This results in the formation of pungent and toxic breakdown products, such as isothiocyanates and nitriles. Currently, more than 130 structurally different glucosinolates have been identified. The chemical structure of the glucosinolate is an important determinant of the product that is formed, which in turn determines its biological activity. The latter may range from detrimental (e.g., progoitrin) to beneficial (e.g., glucoraphanin). Each glucosinolate-containing plant species has its own specific glucosinolate profile. For this reason, it is important to correctly identify and reliably quantify the different glucosinolates present in brassicaceous leaf, seed, and root crops or, for ecological studies, in their wild relatives. Here, we present a well-validated, targeted, and robust method to analyze glucosinolate profiles in a wide range of plant species and plant organs. Intact glucosinolates are extracted from ground plant materials with a methanol-water mixture at high temperatures to disable myrosinase activity. Thereafter, the resulting extract is brought onto an ion-exchange column for purification. After sulfatase treatment, the desulfoglucosinolates are eluted with water and the eluate is freeze-dried. The residue is taken up in an exact volume of water, which is analyzed by high-pressure liquid chromatography (HPLC) with a photodiode array (PDA) or ultraviolet (UV) detector. Detection and quantification are achieved by conducting comparisons of the retention times and UV spectra of commercial reference standards. The concentrations are calculated based on a sinigrin reference curve and well-established response factors. The advantages and disadvantages of this straightforward method, when compared to faster and more technologically advanced methods, are discussed here.

International audience; Plants from the Brassicaceae family are known to contain secondary metabolites called glucosinolates. Our goal was to establish by LC/MS the glucosinolate profile of seeds of three Brassicaceae species known to hyperaccumulate heavy metals. We investigated Alyssum fallacinum auct. non Hausskn., Iberis intermedia Guers., and Noccaea caerulescens (J. Presl & C. Presl) F. K. Mey. Our results indicate that A. fallacinum seeds contain glucoiberin and glucoibervirin, which had not been previously identified in this plant. Furthermore, we report for the first time the presence of glucoiberin, glucoibervirin, glucotropaeolin, and sinigrin in I. intermedia. We have detected for the first time glucoconringiin in N. caerulescens. In addition, glucosinalbin, 4-hydroxyglucobrassicin, and glucomoringin were also detected.

The influence of salinity on the biosynthesis of secondary metabolites with a focus on single glucosinolates (GSLs) was investigated in Lepidium latifolium L., which is a plant species rich in antioxidants. Mature plants were subjected to 0, 15, 22.5, and 35 Practical Salinity Units (PSU) for 1–4 weeks. While phenols, flavonoids, and the oxygen radical absorbance capacity (ORAC) increased with increasing salinity, the ascorbate concentration did not follow a specific pattern. The concentration of single GSLs was influenced by salinity in different ways: While the concentration of aliphatic GSLs like glucoiberin and sinigrin increased, the concentration of aromatic GSLs such as glucobrassicin decreased under salinity stress. Salinity increased the total GSL concentration significantly with sinigrin being the major contributing GSL. The exact molecular role of the different GSLs in abiotic stress defense needs further analysis.

Four loose-curd cauliflower varieties, and one common cauliflower cultivar, were studied to investigate the appearance, antioxidant capacity, and levels of ascorbic acid, chlorophylls, carotenoids and glucosinolates in the florets. The loose-curd cauliflower was typically characterized by a loose curd and long florets with green pedicels and a yellow surface. The levels of total glucosinolates, sinigrin, and neoglucobrassicin were lower in the loose-curd cauliflower varieties than in the common cauliflower. The amount of glucoiberin, major aliphatic glucosinolate, present in loose-curd cauliflower varieties, was 147 to 241 nmol/g dry weight (average: 147 nmol/g dry weight). In contrast, the common cauliflower contained a much higher amount of sinigrin (249 nmol/g dry weight) than glucoiberin (56 nmol/g dry weight). All cauliflower varieties contained minor amounts of progoitrin and neoglucobrassicin. Furthermore, the loose-curd cauliflower varieties exhibited comparably higher levels of ascorbic acid, chl...

Fermentation can reduce the concentration of health-promoting glucosinolates in Brassica vegetables. The endogenous enzyme myrosinase is hypothesised to mainly responsible for the degradation of glucosinolates during fermentation. In order to retain glucosinolates in the final fermented product, the role of myrosinase activity during the production of sayur asin was investigated. Sayur asin is a traditionally fermented product of Indian mustard (Brassica juncea) commonly consumed in Indonesia. It is prepared by a spontaneous fermentation of withered (sun-dried) B. juncea leaves. The leaves of B. juncea contain a substantial amount of the aliphatic glucosinolate sinigrin. Three withering methods were investigated to obtain B. juncea leaves with different myrosinase activities prior to fermentation. Results show that withering by oven at 35 °C for 2.5 h and by microwave at 180 W for 4.5 min reduced myrosinase activity by 84 and 74 %, respectively. Subsequently, sinigrin was not detectable in the leaves after 24 h of incubation in the fermentation medium. However, withering by microwave for 2 min at 900 W inactivated myrosinase completely and produced sayur asin with a sinigrin concentration of 11.4 µmol/10 g dry matter after 7 days of fermentation. This high power-short time pretreatment of B. juncea leaves contributes to the production of sayur asin containing significant levels of health-promoting glucosinolate. In this study, the effect of myrosinase activity during Brassica fermentation was quantified, and optimised production methods were investigated to retain glucosinolate in the final product.

Profile and distribution of glucosinolates (GLS) were detected in plant tissues of horseradish at different developmental stages: beginning of vegetative re-growth, flowering and silique formation. The GLS profile varied widely in the different tissues: we identified 17 GLS in roots and sprouts, one of which was not previously characterized in horseradish, i.e. the 2(S)-hydroxy-2-phenylethyl-GLS (glucobarbarin) and/or 2(R)-hydroxy-2-phenylethyl-GLS (epiglucobarbarin), 11 already found in the roots, including the putative 2-methylsulfonyl-oxo-ethyl-GLS, and 5 previously recognized only in the sprouts. Fifteen of those GLS were also identified in young and cauline leaves, 12 in the mature leaves and 13 in the inflorescences. No difference in GLS profile was observed in plant among the phenological stages. Differences in concentrations of GLS, quantified as desulfated, were found in plant. At the beginning of vegetative re-growth, sprouts while showing the same profile of the roots were much richer in GLS having the highest total GLS concentrations (117.5 and 7.7μmolg(-1) dry weight in sprouts and roots, respectively). During flowering and silique forming stages, the roots still maintained lower amount of total GLS (7.4μmolg(-1) of dry weight, on average) with respect to the epigeous tissues, in which mature and young leaves showed the highest total concentrations (70.5 and 73.8μmolg(-1) of dry weight on average, respectively). Regardless of the phenological stages, the aliphatic GLS were always predominant in all tissues (95%) followed by indolic (2.6%) and benzenic (2.4%) GLS. Sinigrin contributed more than 90% of the total GLS concentration. Aliphatic GLS concentrations were much higher in the epigeous tissues, particularly in the mature and young leaves, while benzenic and indolic GLS concentrations were higher in the roots. Through the phenological stages, GLS concentration increased in young and mature leaves and decreased in cauline leaves and inflorescences, while it remained constant over time in roots.

Glucosinolate (GSL) and antioxidant activity in 62 varieties of Chinese cabbage (Brassica rapa L. ssp. pekinensis) were determined by HPLC and DPPH, HRSA, and FRAP assays. Five aliphatic GSLs: progoitrin, sinigrin, glucoalyssin, gluconapin, and glucobrassicanapin; four indolyl GSLs: 4-hydroxyglucobrassicin, glucobrassicin, 4-methoxyglucobrassicin, and neoglucobrassicin; one aromatic GSL: gluconasturtiin were identified. Glucobrassicanapin and gluconapin documented the most abundant (average 4.52 and 3.72 μmol/g DW, respectively). The contents of total GSLs varied extensively among 62 varieties (range from 2.83 to 48.53 μmol/g DW). Comprehensive differences in total and individual GSL contents have also been observed among different varieties. Indolyl and aromatic GSL together accounted 26% of the total GSLs; but there are few differences among varieties. FC7 and FI17 could be good candidates for future breeding programs since they had a high quantity of glucobrassicin (2.10 and 1.66 μmol/g DW, respectively). Most of the Chinese cabbage varieties showed significant antioxidant activities when compare with positive control. However, three antioxidant assays were not significantly correlated with total GSLs. The presence of significant quantities of glucobrassicin in some varieties should be studied more extensively, since GSL is the precursor of indole-3-carbinol, a potent anticancer isothiocyanate.

Introduction: Brassica juncea is an economically important plant that has been well-known in India for centuries for its medicinal and nutritive values. The broad spectrum of benefi cial effects of the seeds perceived with this plant warrants further exploration of B. juncea seeds as a potential source for obtaining pharmacologically standardized phytotherapeutics, which could be potentially useful. The objective of the present study was to perform the pharmacognosy of mustards seeds inclusive of qualitative and quantitative phytochemical analysis, fi ngerprinting by infrared spectroscopy and high performance thin layer chromatography analysis and toxicity assessment in vitro. Methods: Different sections of seeds were taken and stained with 0.1% phloroglucinol for microscopic examination. The seeds were extracted by 80% alcohol on a rotary shaker to perform phytochemical analysis and fi ngerprinting. The toxicity assessment of this extract was performed on human dermal fi broblast cells. Results: Microscopic examination of seeds showed characteristic features of mustard seeds. The extraction of these seeds by 80% alcohol resulted in IC 50 value of 103 ± 3 μg/mL for 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl radical scavenging assay. The fi ngerprinting analysis of this extract indicated probable presence of sinigrin, quercetin, vanillin, catechin, vitamin E and sulfur-containing compounds. This extract exhibited 50% toxicity (IC 50 ) at 1.79 mg/mL. Conclusion: The result achieved will be used to assess the therapeutic effi cacy of seed extracts for future pharmacological evaluations.

Effect of radiation processing (0.5–2 kGy) and storage on the volatile oil constituents and glucosinolateprofile of cabbage was investigated. Among the volatile oil constituents, an enhancement in trans-hex-2-enal was noted on irradiation that was attributed to the increased liberation of precursor linolenic acidmainly from monogalactosyl diacyl glycerol (MGDG). Irradiation also enhanced sinigrin, the major gluc-osinolate of cabbage that accounted for the enhanced allyl isothiocyanate (AITC) in the volatile oils of theirradiated vegetable. During storage the content of trans-hex-2-enal increased immediately after irradi-ation and then returned to the basal value within 24 h while the content of sinigrin and AITC increasedpost irradiation and thereafter remained constant during storage. Our findings on the enhancement inpotentially important health promoting compounds such as sinigrin and AITC demonstrates that besidesextending shelf life and safety, radiation processing can have an additional advantage in improving thenutritional quality of cabbage. 2013 Elsevier Ltd. All rights reserved.

Armoracia rusticana (horseradish) is a Brassicaceae species cultivated for its roots. It is appreciated for its intense flavour due to the richness of secondary metabolites, such as glucosinolates (GLS) and their breakdown products. Roots of horseradish well suitable for agro-industrial and pharmaceutical sectors are selected based on yield, biometrical characteristics and qualitative composition. Six horseradish accessions from southern Italy were compared based on root traits, yield and GLS concentration. The genetic variability of the accessions was also investigated using the amplified fragment length polymorphism (AFLP) markers. Phenotypically, the six accessions showed significant differences for the sprout number on the crown as well as for the root diameters and length. Among the accessions, wide diversity in total and marketable root yield per plant was also found. The root GLS analysis revealed significant differences for the individual and total GLS concentration. Particularly, this latter ranged from 1.73 to 37.7 μmol g−1 of dry weight, with sinigrin as predominant GLS in all accessions, contributing from 53% to 87% of the total GLS concentration. By using AFLP markers, the percentage of polymorphisms detected was high. The similarity clusters developed based on root biometric characteristics, yield and total GLS concentration was different from the cluster based on AFLP markers. Wide variability among the horseradish accessions was found on the basis of the morphological and qualitative traits, and molecular markers. The genetic diversity of horseradish germplasm still available in the Basilicata region deserves to be preserved and protected against genetic erosion.

Brassica cultivars with varying degrees of partial plant resistance were fed to larvae (up to 4th instar) of the diamondback moth (DBM), Plutella xylostella, and were bioassayed by topical application of cypermethrin to investigate the interaction of plant resistance with insecticide. Larvae reared on the least preferred brassica, Minicole, showed a significantly higher LD50 value than those on the most preferred brassica, Chinese cabbage. Bioassay of 4th instar DBM larvae fed on artificial diet containing pure compounds of glucosinolates revealed a negative interaction between their susceptibility to cypermethin and certain glucosinolates (in particular sinigrin), suggesting that such compounds induced the production of insecticide-detoxifying enzymes.

Glucosinolates (GSLs) represent one of the most widely studied classes of plant secondary metabolite, and have a wide range of biological activities. Their unique properties also affect livestock and human health, and have been harnessed for food and other end-uses. Since GSLs are sulfur (S)-rich there are many lines of evidence suggesting that plant S status plays a key role in determining plant GSL content. However, there is still a need to establish a detailed knowledge of the distribution and remobilization of S and GSLs throughout the development of brassica crops, and to represent this in terms of primary and secondary sources and sinks. The increased genome complexity, gene duplication and divergence within brassicas, together with their ontogenetic plasticity during crop development, appear to have a marked effect on the regulation of S and GSLs. Here we review the current understanding of inorganic S (sulfate) assimilation into organic S forms, including GSLs and their precursors, the intracellular and inter-organ transport of inorganic and organic S forms, and the accumulation of GSLs in specific tissues. We present this in the context of overlapping sources and sinks, transport processes, signaling molecules and their associated molecular interactions. Our analysis builds on recent insights into the molecular regulation of sulfate uptake and transport by different transporters, transcription factors (TF) and miRNAs, and the role that these may play in GSL biosynthesis. We develop a provisional model describing the key processes that could be targeted in crop breeding programs focused on modifying GSL content.

Glucosinolates (GLSs), health promoting compounds commonly found in Brassica vegetables, were studied during sayur asin fermentation made from Indian mustard (B. juncea). The current preliminary study aims to investigate the changes of glucosinolates content during 3 and 7 days of fermentation in two different media, i.e. coconut water and tajin liquor, and salt concentrations of 2.5 and 10%. The glucosinolates were analysed by HPLC after sample extraction in hot methanol followed by purification and de-sulphation. Results show that sinigrin was the most dominant glucosinolate among others, i.e. gluconapin, glucobrassicin, 4-hydroxy-glucobrassicin, 4-methoxy-glucobrassicin, and neo glucobrassicin, accounting for about 1000 and 4000 µmol/10 g dw in raw Indian mustard. Unfortunately, fermentation has substantially reduced the glucosinolates content in sayur asin. After 3 days of fermentation the sinigrin content was reduced by 95% as compared to that in the raw vegetable. The indole GLSs 4-methoxy-glucobrassicin and neo-glucobrassicin concentration decreased to 80-90% of the fresh materials. However, the decreasing mechanisms as well as factors contributing to the decrease of the glucosinolates could not be explained yet.

The total content and the composition of the constituents of glucosinolates were analyzed in 51 samples of 6 species of 5 genera of the Brassicaceae family. The twenty-one component of the profile of glucosinolates, including fifteen aliphatic glucosinolates, four insole glucosinolates, and two aromatic glucosinolates, were revealed. The wide potential of variability of the constituent composition of glucosinolates was found, which allows to use the cabbage plants to various purposes, such as a valuable foodstuff and for fumigation of soils. All studied samples of Sinapsis alba L. and six samples of Brassica juncea Czen, which possess a high (more than 40 I¼mol/g) concentration of sinalbin and sinigrin, correspondingly, are recommended for biofumigation. It was revealed that the glucosinolates of Brassica rapa L. contain 17 constituents. For the first time, samples of the variety that have an increased value of constituent composition of glucosinolates for balanced food of people were found. These varieties are recommended for use in breeding, including for medical purposes, and for the completion of assortment of cabbage vegetables.

Armoracia rusticana (horseradish), a member of the Brassicaceae family, has been known since ancient times as a folk medicinal herb and as a plant of nutritional value and culinary interest. Currently horseradish is cultivated for its thick, fleshy and white roots which have a delicious intense pungency and for its tender leaves which are frequently used for salad mixed to other vegetables. The traditions to use horseradish plant for medicinal purpose are still applied in many countries. Horseradish is a rich source of a number of bioactive compounds such as glucosinolates (GLSs) and their breakdown products. Sinigrin is the dominant glucosinolate in both leaves and roots. Recent studies have shown that crude plant extracts have a complex profile of naturally occurring GLSs, with particular regard to sprouts. The increasing interest in these secondary metabolites, associated to the long and diffuse tradition of using horseradish in food preservation and as condiment in many parts of the world, is generating new applications of this plant in several agro-industrial and pharmaceutical sectors and is encouraging the use of its roots and leaves in functional food and medicine for human health. A bibliography review is discussed on ethnobotanical aspects and uses of this plant, as well as knowledge about its flavour compounds and GLS content and composition. This study summarizes also the updated information concerning the influence of the genotype and environment on GLS profile in horseradish.

Members of the Brassicaceae are known for their contents of nutrients and health-promoting phytochemicals, including glucosinolates. The concentrations of these chemopreventive compounds (glucosinolate-degradation products, the bioactive isothiocyanates) may be modified under salinity. In this work, the effect of the aliphatic glucosinolate sinigrin (2-propenyl-glucosinolate) on plant water balance, involving aquaporins, was explored under salt stress. For this purpose, water uptake and its transport through the plasma membrane were determined in plants after NaCl addition, when sinigrin was also supplied. We found higher hydraulic conductance (L0 ) and water permeability (Pf ) and increased abundance of PIP2 aquaporins after the direct administration of sinigrin, showing the ability of the roots to promote cellular water transport across the plasma membrane in spite of the stress conditions imposed. The higher content of the allyl-isothiocyanate and the absence of sinigrin in the plant tissues suggest that the isothiocyanate is related to water balance; in fact, a direct effect of this nitro-sulphate compound on water uptake is proposed. This work provides the first evidence that the addition of a glucosinolate can regulate aquaporins and water transport: this effect and the mechanism(s) involved merit further investigation.

A total of 95 broccoli (Brassica oleracea L. var. italica) accessions were evaluated for the identification of desulfo-glucosinolates and their content variation in the flower head using ultra performance liquid chromatography, to select the potentially functional broccoli breeding lines. The six individual desulfo-glucosinolates, including progoitrin, glucoraphanin, sinigrin, gluconapin, glucobrassicanapin, and glucobrassicin, were commonly identified, based on the chromatogram peak comparison with those of the nine individual glucosinolate standards. The total glucosinolate contents varied from 4.2 to 29.0 μmol·8g -1 DW and the glucoraphanin (1.6 to 13.9 μmol·g -1 DW) was confirmed as a major constituent in the total glucosinolate profile among the six identified individual glucosinolate species, whereas the progoitrin, which was only detected in 13 accessions, showed accession-specific variation and negative correlation with glucoraphanin content. It was also revealed that the four major glucosinolates, such as glucobrassicanapin, glucoraphanin, glucobrassicin, and gluconapin, affected major content variation and showed higher positive inter-correlation. These results might be used for the selection of potential breeding materials as functional broccoli germplasm through the further evaluation on the stability and reproducibility of glucosinolate profile depending on environmental factors or cultural managements using the selected accessions.

Glucosinolates have anti-carcinogenic properties. In the recent decades, the genetics of glucosinolate biosynthesis has been widely studied, however, the expression of specific genes involved in glucosinolate biosynthesis under exogenous phytohormone treatment has not been explored at the subspecies level in Brassica oleracea. Such data are vital for strategies aimed at selective exploitation of glucosinolate profiles. This study quantified the expression of 38 glucosinolate biosynthesis-related genes in three B. oleracea subspecies, namely cabbage, broccoli and kale, and catalogued associations between gene expression and increased contents of individual glucosinolates under methyl jasmonate (MeJA) and salicylic acid (SA) treatments. Glucosinolate accumulation and gene expression in response to phytohormone elicitation was subspecies specific. For instance, cabbage leaves showed enhanced accumulation of the aliphatic glucoiberin, progoitrin, sinigrin and indolic neoglucobrassicin under both MeJA and SA treatment. MeJA treatment induced strikingly higher accumulation of glucobrassicin (GBS) in cabbage and kale and of neoglucobrassicin (NGBS) in broccoli compared to controls. Notably higher expression of ST5a (Bol026200), CYP81F1 (Bol028913, Bol028914) and CYP81F4 genes was associated with significantly higher GBS accumulation under MeJA treatment compared to controls in all three subspecies. CYP81F4 genes, trans-activated by MYB34 genes, were expressed at remarkably high levels in all three subspecies under MeJA treatment, which also induced in higher indolic NGBS accumulation in all three subspecies. Remarkably higher expression of MYB28 (Bol036286), ST5b, ST5c, AOP2, FMOGS-OX5 (Bol031350) and GSL-OH (Bol033373) was associated with much higher contents of aliphatic glucosinolates in kale leaves compared to the other two subspecies. The genes expressed highly could be utilized in strategies to selectively increase glucosinolate compounds in B. oleracea subspecies. These results promote efforts to develop genotypes of B. oleracea and other species with enhanced levels of desired glucosinolates.