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Cerebral ischaemia‐reperfusion (CIR) injury occurs in stroke patients after the restoration of cerebral perfusion. Sinigrin, a phytochemical found in cruciferous vegetables, exhibits strong antioxidant activity. This study investigated the role of sinigrin in oxidative stress using a CIR injury model. The effects of sinigrin were studied in middle cerebral artery occlusion (MCAO) rats and oxygen–glucose deprivation/reoxygenation (OGD/R)‐injured SH‐SY5Y cells. Sinigrin treatment improved brain injury and neurological deficits induced by MCAO surgery in rats. Sinigrin inhibited apoptosis in brain tissues and SH‐SY5Y cells following OGD/R induction. Additionally, sinigrin elevated the levels of superoxide dismutase (SOD), glutathione (GSH) and glutathione peroxidase (GSH‐Px) while reducing malondialdehyde (MDA) levels. Furthermore, sinigrin inhibited the toll‐like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88) signalling pathway. The anti‐apoptotic and antioxidant activities of sinigrin in OGD/R‐injured SH‐SY5Y cells were reversed by TLR4 overexpression. In conclusion, sinigrin inhibits oxidative stress in CIR injury by suppressing the TLR4/MyD88 signalling pathway. [ABSTRACT FROM AUTHOR]

Introduction: Glucosinolates (1–5) are important secondary metabolites found in Isatis indigotica roots. Due to their high hydrophilic and ionic nature, purified glucosinolates often contain salt impurities and moisture. Accurate assessment of their purities is important for glucosinolates being utilised as chemical markers. Objective: To develop and validate quantitative proton (1H) nuclear magnetic resonance (qHNMR) methods for purity assessments of aliphatic and indole glucosinolates (1–5). Method: Several NMR parameters such as pulse program, relaxation time, and delay time were optimised. Three qHNMR methods were developed using gluconapin (3), neoglucobrassicin (4), and sinigrin (5) for method validation and with maleic acid as internal standard. Results: The quantification was based on the integrated area ratios of an olefinic proton (H‐4 for 1–3; H‐6 for 4; and H‐3 for 5) of the side chain from glucosinolates relative to the olefinic proton from the internal standard using deuterated water (D2O) as the solvent. The qHNMR methods were successfully applied for purity assessments of four aliphatic glucosinolates (1–3 and 5: progoitrin, epiprogoitrin, gluconapin, and sinigrin), and an indole glucosinolate (4: neoglucobrassicin). Conclusion: The purity of glucosinolates isolated from I. indigotica and commercial sinigrin was accurately assessed using the developed qHNMR method. The qHNMR provides a reliable and superior means to determine the purity of glucosinolates. Three qHNMR methods were developed and validated for purity assessment of aliphatic and indole glucosinolates using maleic acid as internal standard. The quantification was based on integrated area ratios of an olefinic proton of the side chain from glucosinolates relative to the olefinic proton from internal standard. The qHNMR method is a simple, rapid, irreplaceable, and accurate approach for purity assessments of glucosinolates. [ABSTRACT FROM AUTHOR]

A plant's chemical‐based resistance against insects can be characterized by an accumulation of phytochemicals that can severely harm or deter the generalist and non‐adapted specialist insects. In the absence of an herbivore threat, plants maintain a basic concentration of defensive compounds as a constitutive resistance mechanism. On the other hand, plants are capable of sharply increasing their production of defensive compounds as induced defence in response to herbivore attacks. In this study, we highlight the role of chemical‐based defence by comparing the constitutive and herbivore‐induced resistances of cauliflower (Brassica oleracea var. botrytis L.) and yellow cress (Rorippa dubia (Persoon)) with respect to time‐dependent changes of phytochemicals that directly influence the performance of the generalist herbivore insect, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae). The results of the study showed that both plant species were able to switch, albeit different degrees, between constitutive and induced resistances to combat herbivore attack. Brassica oleracea amassed lesser defensive compounds of constitutive resistance (trypsin inhibitor, polyphenol oxidase and sinigrin) than R. dubia. This led to a higher relative growth rate (RGR) of the S. litura larvae fed on cauliflower than in those fed on yellow cress. Brassica oleracea also demonstrated a lower induced response capability than R. dubia in its production of allelochemicals in herbivore‐induced resistances. This was shown by the decrease of the RGR of larvae fed on induced foliage of the cauliflower compared to those fed on yellow cress. These results of the study proved and added to the belief that modern crop variety is not only lower in constitutive resistance but also weaker in induced resistance capability against herbivores, which is likely to be an effect of domestication even Rorippa and Brassica are relatively far from each other in Brassicaceae phylogeny. [ABSTRACT FROM AUTHOR]

Evolutionary traps arise when organisms use novel, low‐quality or even lethal resources based on previously reliable cues. Persistence of such maladaptive interactions depends not only on how individuals locate important resources, such as host plants, but also the mechanisms underlying poor performance. Pieris macdunnoughii (Remington) (Lepidoptera: Pieridae) lays eggs on a non‐native mustard, Thlaspi arvense (L.) (Brassicaceae), which is lethal to the larvae. We first tested whether larval feeding behavior was affected before (pre‐) ingestion or following (post‐) ingestion of leaf material, indicating activity of feeding deterrents, toxins, or both in this evolutionary trap. Neonates were less likely to start feeding and eventually fed more slowly on T. arvense than on the native host plant Cardamine cordifolia (Gray) (Brassicaceae) in both laboratory and field. Starvation was a primary cause of mortality, indicating the role of a feeding deterrent. Feeding did not differ between larvae from invaded and uninvaded population. Second, T. arvense defensive chemistry is dominated by the glucosinolate sinigrin (allyl or 2‐propenyl glucosinolate). Adding sinigrin to the leaves of T. arvense and native hosts C. cordifolia and Descurainia incana (Bernhardi ex Fischer & Meyer) (Brassicaceae) delayed the onset of feeding, caused larvae to feed more slowly, and decreased survival on the native hosts. This evolutionary trap may not be driven by a novel deterrent, but rather by a change in the concentration of a deterrent found in native hosts. Many insects have adapted to evolutionary traps posed by invasive plants, incorporating the new plant into their diets. Thlaspi arvense remains lethal to P. macdunnoughii, and pre‐ingestive deterrents such as excess sinigrin may contribute to persistent maladaptation. [ABSTRACT FROM AUTHOR]

Summary: Coevolution can promote long‐term coexistence of two competing species if selection acts to reduce the fitness inequality between competitors and/or strengthen negative frequency dependence within each population. However, clear coevolution between plant competitors has been rarely documented. Plant invasions offer opportunities to capture the process of coevolution. Here we investigated how the developing relationship between an invasive forb, Alliaria petiolata, and a native competitor, Pilea pumila, may affect their long‐term coexistence, by testing the competitive effects of populations of varying lengths of co‐occurrence on each other across a chronosequence of invasion history. Alliaria petiolata and P. pumila tended to develop greater tolerance to competition over invasion history. Their coexistence was promoted more by increases in stabilizing relative to equalizing processes. These changes likely stem in part from reductions in allelopathic traits in the invader and evolution of tolerance in the native. These results suggested that some native species can evolve tolerance against the competitive effects of strong invaders, which likely promoted their persistence in invaded communities. However, the potential for coevolutionary rescue of competing populations is likely to vary across native species, and evolutionary processes should not be expected to compensate for the ecological consequences of exotic invasions. [ABSTRACT FROM AUTHOR]

Abstract: The fitness of natural enemies should be altered in response to changes in herbivore quality induced by the impact of increased atmospheric CO2 levels on plants. We studied the effect of different CO2 levels on the aphid predator Episyrphus balteatus DeGeer fed either specialist or generalist aphids reared on either of two host plants under laboratory conditions. In the host plant that contains sinigrin (black mustard), elevated CO2 increased the sinigrin content of both host plant and the specialist aphid, but reduced the already very low levels in the generalist aphid. Predator development time increased with elevated CO2, while fecundity decreased. Consequently, individual fitness decreased slightly with increasing atmospheric CO2. Sinigrin significantly decreased fecundity and increased development time of the predator. As a result, fitness was significantly lower too. The consumption rate was influenced significantly by plant and prey solely and the interactions of host plant × prey type and CO2 level × prey type. Further research on the effects of climate change parameters (e.g. greenhouse gases such as CO2, ozone (O3) and nitrogen dioxide (NO2), etc.) separately and jointly under controlled environmental conditions will help to understand the nature and direction of their effects on natural enemies as part of the tritrophic system. [ABSTRACT FROM AUTHOR]

The endoplasmic reticulum body (ER body) is an organelle derived from the ER that occurs in only three families of the order Brassicales and is suggested to be involved in plant defense. ER bodies in Arabidopsis thaliana contain large amounts of β-glucosidases, but the physiological functions of ER bodies and these enzymes remain largely unclear. Here we show that PYK10, the most abundant β-glucosidase in A. thaliana root ER bodies, hydrolyzes indole glucosinolates (IGs) in addition to the previously reported in vitro substrate scopolin. We found a striking co-expression between ER body-related genes (including PYK10), glucosinolate biosynthetic genes and the genes for so-called specifier proteins affecting the terminal products of myrosinase-mediated glucosinolate metabolism, indicating that these systems have been integrated into a common transcriptional network. Consistent with this, comparative metabolite profiling utilizing a number of A. thaliana relatives within Brassicaceae identified a clear phylogenetic co-occurrence between ER bodies and IGs, but not between ER bodies and scopolin. Collectively, our findings suggest a functional link between ER bodies and glucosinolate metabolism in planta. In addition, in silico three-dimensional modeling, combined with phylogenomic analysis, suggests that PYK10 represents a clade of 16 myrosinases that arose independently from the other well-documented class of six thioglucoside glucohydrolases. These findings provide deeper insights into how glucosinolates are metabolized in cruciferous plants and reveal variation of the myrosinase-glucosinolate system within individual plants. [ABSTRACT FROM AUTHOR]

The oomycete plant pathogen Phytophthora cinnamomi causes a highly destructive root rot that affects numerous hosts. Integrated management strategies are needed to control P. cinnamomi in seminatural oak rangelands. We tested how biofumigation affects crucial stages of the pathogen's life cycle in vitro, in infested soils under laboratory conditions and in planta. Different genotypes of three potential biofumigant plant species ( Brassica carinata, Brassica juncea, Brassica napus) were collected at different phenological stages, analysed for their glucosinolate contents, and subsequently tested. The most effective genotypes against mycelial growth and sporangial production were further tested on the viability of chlamydospores in artificially infested natural soils and in planta on Lupinus luteus, a host highly susceptible to P.cinnamomi. Brassica carinata and B. juncea genotypes inhibited mycelial growth, decreased sporangial production, and effectively inhibited the viability of chlamydospores in soil, but only B. carinata decreased disease symptoms in plants. Effective genotypes of Brassica had high levels of the glucosinolate sinigrin. Biofumigation with Brassica plants rich in sinigrin has potential to be a suitable tool for control of oak root disease caused by P. cinnamomi in Spanish oak rangeland ecosystems. [ABSTRACT FROM AUTHOR]

Ecological and evolutionary processes historically have been assumed to operate on significantly different time-scales. We know now from theory and work in experimental and model systems that these processes can feed back on each other on mutually relevant time-scales., Here, we present evidence of a soil-mediated eco-evolutionary feedback on the population dynamics of an invasive biennial plant, Alliaria petiolata., As populations age, natural selection drives down production of A. petiolata's important antimycorrhizal allelochemical, sinigrin. This occurs due to density-dependent selection on sinigrin, which is favoured under interspecific, but disfavoured under intraspecific, competition., We show that population stochastic growth rates (λS) and plant densities are positively related to sinigrin concentration measured in seedling roots. This interaction is mediated by sinigrin's positive effect on seedling and summer survival, which are important drivers of λS., Together, these illustrate how the evolution of a trait shaped by natural selection can influence the ecology of a species over a period of just years to decades, altering its trajectory of population growth and interactions with the species in the soil and plant communities it invades., Our findings confirm the predictions that eco-evolutionary feedbacks occur in natural populations. Furthermore, they improve our conceptual framework for projecting future population growth by linking the variation in plant demography to a critical competitive trait (sinigrin) whose selective advantages decrease as populations age. [ABSTRACT FROM AUTHOR]

1. Plant secondary metabolites can govern prey-predator interactions by altering the diet breadth of predators and sometimes provide an ecological refuge to prey. Brassicaceae plants and their specialist pests can be used as a model system for understanding the role of chemically mediated effects restricting the diet breadth of natural enemies, and consequently the occurrence of enemy-free space for the specialist pest. 2. The objective of the present study was to test the performance of the generalist predator Episyrphus balteatus De Geer ( Diptera: Syrphidae) fed on the specialist herbivore Brevicoryne brassicae L.( Homoptera: Aphididae), reared on two different brassica species: black mustard ( Brassica nigra), a wild species with high levels of sinigrin; and canola ( Brassica napus), a cultivated species without sinigrin. 3. The preference and performance of the predator and the performance of the prey were measured. Sinigrin was quantified by high-performance liquid chromatography in both leaf samples and aphids reared on the two host plants. 4. The cabbage aphid performed better on canola than on black mustard. The performance of the predator on this aphid when reared on canola was clearly better than when reared on black mustard. Females had a higher overall preference for cabbage aphids reared on canola than on black mustard. 5. The ability of aphids reared on plants with high glucosinolate content to reduce the performance of their generalist predators indicates that the presence of B. nigra may provide enemy-free space for the cabbage aphid from its predator, a concept that has useful application in the context of biological control for agricultural systems. [ABSTRACT FROM AUTHOR]

An ion-pair reversed-phase high-performance liquid chromatography ( HPLC) method was developed for the analysis of sinigrin in Ethiopian mustard ( Brassica carinata A. Braun) seed and seed fractions. Separation was compared on several RP- HPLC columns (Inertsil® ODS-4 C18 and ZORBAX® Eclipse XDB-C18) with an isocratic eluent containing 100% aqueous (aq.) tetramethylammonium bromide (10 m m, pH 5.0). Sinigrin retention was affected by HPLC variables including the type of ion-pair reagent, buffer strength and pH, acetonitrile concentration, column temperature and eluent flow rate. Partial validation demonstrated this optimised chromatographic condition to be linear, accurate and precise. Multistage extraction using 70% (v/v) aq. methanol was more efficient than 50% (v/v) aq. acetonitrile. In addition, the matrix effect and recovery rate as well as processing efficiency of the analytical protocol were determined. This method is suitable for high throughput analysis of sinigrin in Ethiopian mustard seed and seed fractions. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Recently, controlled production of plants to enhance specific ingredients, such as sinigrin in Wasabi effective for antibacterial and anticancer, in the plants has become more important in order to use the ingredients efficiently. It is, however, difficult to develop a plant production method for controlling the sinigrin amount, because the sinigrin production mechanism is not clear. Therefore, it is crucial to evaluate distribution and metabolic pathways of sinigrin and related molecules in the wasabi tissue. Because time-of-flight (ToF)-SIMS provides molecular distributions of insulation samples including plant tissues on a submicron scale, it is useful for such a purpose. On the other hand, interpretation of intricate ToF-SIMS spectra of complex samples is often difficult. Recently, multivariate analysis techniques, such as principal component analysis and multivariate curve resolution, successfully applied into a variety of scientific fields have been also introduced into ToF-SIMS data. Moreover, gentle secondary ion mass spectrometry (G-SIMS), developed for analyzing static-SIMS spectra in terms of the degree of fragmentation, has recently been applied to various samples. In this study, sections of Wasabi petioles were evaluated with ToF-SIMS and the data analysis techniques to clarify the distribution of sinigrin molecule in the wasabi tissue. A combination of multivariate analysis and G-SIMS worked effectively to interpret the complex ToF-SIMS data of the plant tissue. As a result, the detailed distribution of sinigrin in the plant tissue was indicated by ToF-SIMS and the data analysis techniques. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Direct analysis in real time (DART) is a novel technique with great potential for rapid screening analysis. The DART ionization method coupled with high-resolution time-of-flight mass spectrometry (TOF-MS) has been used for characterization of mustard seeds and table mustard. The possibility to use DART to analyse glucosinolates was confirmed on determination of sinalbin (4-hydroxybenzyl glucosinolate). The DART-TOF-MS method was optimized and validated. A set of samples of mustard seeds and mustard products was analyzed. High-performance liquid chromatography and DART-TOF-MS were used to determine glucosinolates in mustard seeds and compared. The correlation equation between these methods was DART = 0.797*HPLC + 6.987, R2 = 0.972. The DART technique seems to be a suitable method for evaluation of the quality of mustard seeds and mustard products. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

BACKGROUND: Horseradish plants ( Armoracia rusticana) contain high concentrations of glucosinolates. Former studies have revealed that Armoracia plants cultivated in vitro have markedly lower glucosinolate concentrations than those grown in soils. Yet, these studies neglected that the sulfate concentration in the growth medium may have had a strong impact on glucosinolate metabolism. Accordingly, in this study horseradish in vitro plants were cultivated with differing sulfate concentrations and the glucosinolate concentrations were quantified by ion pair HPLC. RESULTS: Cultivation in 1.7 mmol L−1 sulfate (as used in the prior studies) resulted in the accumulation of 16.2 µmol g−1 DW glucosinolates, while the glucosinolate concentration increased to more than 23 µmol g−1 DW when 23.5 mmol L−1 sulfate was used in the medium. Correspondingly, the glucosinolate concentration decreased to 1.6 µmol g−1 DW when sulfate concentration was lowered to 0.2 mmol L−1. CONCLUSION: Since the glucosinolate accumulation in relation to the sulfate concentration follows a typical saturation curve, we deduce that the availability of sulfate determines the glucosinolate concentration in horseradish in vitro plants. © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

1 Foliar nitrogen concentration, which can be manipulated in crop plants by fertilizer supply, has long been recognized as a major factor in phytophagous insect abundance and performance. More recently, the type of fertilizer supplied has been shown to influence the abundance of some herbivore species. The diamondback moth Plutella xylostella is a global pest of Brassica crops. Although it has been the subject of numerous studies on host-plant resistance and pest control, few studies have addressed the effect of abiotic factors, such as nutrient supply, on its performance and behaviour. 2 We assessed oviposition preference, larval feeding preference and larval performance of P. xylostella on two cultivars of Brassica oleracea. Plants were grown using two fertilizer types, John Innes fertilizer and an organic animal manure, at high and low concentrations. 3 Plutella xylostella laid more eggs on cultivar Derby Day than Drago. Derby Day was also the cultivar on which larval performance was maximized. However, differences in larval performance between cultivars were only found when plants were grown in compost with John Innes fertilizer, and not when fertilized with animal manure. 4 Foliar nitrogen concentration was greater in plants grown in high fertilizer treatments but did not differ between cultivars. The concentrations of three glucosinolate compounds (glucoiberin, sinigrin and glucobrassicin) were greater in the high fertilizer treatments. Glucosinolate concentrations were higher in the Drago than the Derby Day cultivar. 5 These results are discussed in relation to the preference-performance hypothesis, and the assessment of plant resistance differences between cultivars using different types of fertilizer. [ABSTRACT FROM AUTHOR]

Seed meal amendments rich in glucosinolates are of interest for soil pest and disease control. The Ethiopian mustard ( Brassica carinata A. Braun) line N2-6215, with very high levels of seed glucosinolates (160 μmol/g), was developed from the line C-101 (116 μmol/g) following mutagenesis. The objective of this research was to study the inheritance of very high seed glucosinolate content. Plants of N2-6215 were reciprocally crossed with plants of the line C-101. The F1, F2, and BC1F1 plant generations were evaluated in two environments and seeds from individual plants were analysed for total glucosinolate content. The very high glucosinolate content in N2-6215 seeds was largely subject to maternal control. No cytoplasmic effects were detected. The trait was found to be oligogenic and determined by at least two or three genes. The estimates of broad-sense heritability were 0.45 and 0.58 in both environments, whereas the estimates of narrow-sense heritability were 0.35 and 0.50. The moderate heritability and oligogenic control of the trait suggest the feasibility of breeding for increased seed glucosinolate content in Ethiopian mustard. [ABSTRACT FROM AUTHOR]

The importance of non-resource-based mechanisms of competition between plant species has been increasingly recognized, but little is known about how genetic variation and evolutionary changes in the underlying competitive traits might affect species coexistence. I found that genetic variation in sinigrin concentration, a putative allelopathic agent in Brassica nigra, affected the fitness of three heterospecific neighbor species but did not affect neighboring B. nigra individuals. Investment in sinigrin led to a negative genetic correlation between intra- and interspecific competitive ability, which over many generations could provide a strong stabilizing force maintaining both species and genetic diversity in this system. [ABSTRACT FROM AUTHOR]

The individual glucosinolates present in B. juncea mustard seed were determined. Sinigrin (ally1 glucosinolate) was the major glucosinolate of mustard seed and constituted 92.9% of the total glucosinolates. The effect of CH3OH/NH3H2O-hexane treatment on the concentration of glucosinolates was studied. Over 97% of sinigrin originally present in the seed was removed by the above solvent extraction system, mainly in the intact form. Breakdown products of sinigrin were quantified in the treated meal, in the extracted oil and in the polar phase (gums). Aglycon products were ally1 cyanide, ally1 isothiocyanate and 2,3-epithiopropane cyanide. Sugar breakdown products were glucose, thioglucose, thioglucose dimer and furfuryl alcohol. Desulfosinigrin was a minor decomposition product and might have acted as an intermediate in the decomposition of sinigrin. [ABSTRACT FROM AUTHOR]