Glucosinolates, myrosinase hydrolysis products, and flavonols found in rocket (Eruca sativa and Diplotaxis tenuifolia)

Rocket species have been shown to have very high concentrations of glucosinolates and flavonols, which have numerous positive health benefits with regular consumption. In this review we highlight how breeders and processors of rocket species can utilize genomic and phytochemical research to improve varieties and enhance the nutritive benefits to consumers. Plant breeders are increasingly looking to new technologies such as HPLC, UPLC, LC-MS and GC-MS to screen populations for their phytochemical content to inform plant selections. Here we collate the research that has been conducted to-date in rocket, and summarise all glucosinolate and flavonol compounds identified in the species. We emphasize the importance of the broad screening of populations for phytochemicals and myrosinase degradation products, as well as unique traits that may be found in underutilized gene bank resources. We also stress that collaboration with industrial partners is becoming essential for long-term plant breeding goals through research.

Use of synteny to identify candidate genes underlying QTL controlling stomatal traits in faba bean (Vicia faba L.)

Key message We have identified QTLs for stomatal characteristics on chromosome II of faba bean by applying SNPs derived from M. truncatula , and have identified candidate genes within these QTLs using synteny between the two species. Abstract Faba bean (Vicia faba L.) is a valuable food and feed crop worldwide, but drought often limits its production, and its genome is large and poorly mapped. No information is available on the effects of genomic regions and genes on drought adaptation characters such as stomatal characteristics in this species, but the synteny between the sequenced model legume, Medicago truncatula, and faba bean can be used to identify candidate genes. A mapping population of 211 F5 recombinant inbred lines (Mélodie/2 × ILB 938/2) were phenotyped to identify quantitative trait loci (QTL) affecting stomatal morphology and function, along with seed weight, under well-watered conditions in a climate-controlled glasshouse in 2013 and 2014. Canopy temperature (CT) was evaluated in 2013 under water-deficit (CTd). In total, 188 polymorphic single nucleotide polymorphisms (SNPs), developed from M. truncatula genome data, were assigned to nine linkage groups that covered ~928 cM of the faba bean genome with an average inter-marker distance of 5.8 cM. 15 putative QTLs were detected, of which eight (affecting stomatal density, length and conductance and CT) co-located on chromosome II, in the vicinity of a possible candidate gene—a receptor-like protein kinase found in the syntenic interval of M. truncatula chromosome IV. A ribose-phosphate pyrophosphokinase from M. truncatula chromosome V, postulated as a possible candidate gene for the QTL for CTd, was found some distance away in the same chromosome. These results demonstrate that genomic information from M. truncatula can successfully be translated to the faba bean genome.

Identification and quantification of glucosinolate and flavonol compounds in rocket salad (Eruca sativa, Eruca vesicaria and Diplotaxis tenuifolia) by LC–MS: Highlighting the potential for improving nutritional value of rocket crops

Liquid Chromatography Mass Spectrometry (LC-MS) was used to obtain glucosinolate and flavonol content for 35 rocket accessions and commercial varieties. 13 glucosinolates and 11 flavonol compounds were identified. Semi-quantitative methods were used to estimate concentrations of both groups of compounds. Minor glucosinolate composition was found to be different between accessions; concentrations varied significantly. Flavonols showed differentiation between genera, with Diplotaxis accumulating quercetin glucosides and Eruca accumulating kaempferol glucosides. Several compounds were detected in each genus that have only previously been reported in the other. We highlight how knowledge of phytochemical content and concentration can be used to breed new, nutritionally superior varieties. We also demonstrate the effects of controlled environment conditions on the accumulations of glucosinolates and flavonols and explore the reasons for differences with previous studies. We stress the importance of consistent experimental design between research groups to effectively compare and contrast results.

A SNP-based consensus genetic map for synteny-based trait targeting in faba bean (Vicia faba L.)

Faba bean (Vicia faba L.) is a globally important nitrogen-fixing legume, which is widely grown in a diverse range of environments. In this work, we mine and validate a set of 845 SNPs from the aligned transcriptomes of two contrasting inbred lines. Each V. faba SNP is assigned by BLAST analysis to a single Medicago orthologue. This set of syntenically anchored polymorphisms were then validated as individual KASP assays, classified according to their informativeness and performance on a panel of 37 inbred lines, and the best performing 757 markers used to genotype six mapping populations. The six resulting linkage maps were merged into a single consensus map on which 687 SNPs were placed on six linkage groups, each presumed to correspond to one of the six V. faba chromosomes. This sequence-based consensus map was used to explore synteny with the most closely-related crop species, lentil, and the most closely related fully sequenced genome, Medicago. Large tracts of uninterrupted colinearity were found between faba bean and Medicago, making it relatively straightforward to predict gene content and order in mapped genetic interval. As a demonstration of this, we mapped a flower colour gene to a 2 cM interval of Vf chromosome 2 which was highly collinear with Mt3. The obvious candidate gene from 77 gene models in the collinear Medicago chromosome segment was the previously characterized MtWD40-1 gene (Mt3g092830, Mt3g092840) controlling anthocyanin production in Medicago and re-sequencing of the Vf orthologue showed a putative causative deletion of the entire 5’ end of the gene.

Flanking SNP markers for vicine–convicine concentration in faba bean (Vicia faba L).

The pyrimidine glycosides, vicine and convicine, limit the use of faba bean (Vicia faba L.) as food and feed. A single recessive gene, vc-, is responsible for a lowered vicine–convicine concentration. The biosynthetic pathway of these closely related compounds is not known, and the nearest available markers are several cM away from vc-. Improved markers would assist breeding and help to identify candidate genes. A segregating population of 210 F5 recombinant inbred lines was developed from the cross of Mélodie/2 (low vicine–convicine) × ILB 938/2 (normal vicine–convicine), and vicine–convicine concentrations were determined twice on each line. The population was genotyped with a set of 188 SNPs. A strong, single QTL for vicine–convicine concentration was identified on chromosome I, flanked by markers 1.0 cM away on one side and 2.6 cM on the other. The interval defined by these markers in the model species Medicago truncatula includes about 340 genes, but no candidate genes were identified. Further fine mapping should lead to the identification of tightly linked markers as well as narrowing down the search for candidate regulatory or biosynthetic genes which could underlie the vc- locus.

Use of TD-GC-TOF-MS to assess volatile composition during post harvest storage in seven accessions of rocket salad (Eruca sativa)

An important step in breeding for nutritionally enhanced varieties is determining the effects of the post-harvest supply chain on phytochemicals and the changes in VOCs produced over time. TD- GC-TOF-MS was used and a technique for the extraction of VOCs from the headspace using portable tubes is described. Forty-two compounds were detected; 39 were identified by comparison to NIST libraries. Thirty-five compounds had not been previously reported in Eruca sativa. Seven accessions were assessed for changes in headspace VOCs over 7 days. Relative amounts of VOCs across 3 time points were significantly different - isothiocyanate-containing molecules being abundant on 'Day 0'. Each accession showed differences in proportions/types of volatiles produced on each day. PCA revealed a separation of VOC profiles according to the day of sampling. Changes in VOC profiles over time could provide a tool for assessment of shelf-life.

In vitro allelopathic potential of Leonurus sibiricus L. leaves

The chemical interaction between plants is known as allelopathy and it is related to the release of substances into the environment. The present study aimed at the evaluation of the allelopathic activity of the leaves of Leonurus sibiricus against the germination and initial growth of Raphanus sativus, Lactuca sativa, and Lepidium sativum. Chemical analyses showed the presence in the leaves of four major flavonoids (quercetin-3-O-alpha-L-rhamnopyranosyl-(1 > 6)-beta-D-galactopyranoside; rutin; hyperin, and isoquercetrin) and of three minor flavonoidic compounds (genkwanin, 3'-hydroxy genkwanin, and quercetin). Extracts, their chromatographic fractions and pure isolated flavonoids showed different biological activities. A methanol extract of leaves of Leonurus sibiricus caused significant reduction only in the germination of Lactuca sativa, with no effects on the germinative processes of Raphanus sativus and Lepidium sativum. Some chromatographic fractions, containing the flavonoids, showed inhibitory activity on the initial stages of root growth of all tested seeds. The isolated flavonoids, at the higher concentration tested (10(-4) M) seemed to be responsible for the inhibition of the germination, as well as the radical elongation. Among pure compounds, 3'-OH-genkwanin and quercetin showed the stronger antigerminative activity at the concentration of 10(-4) M, whereas the radical elongation was reduced by rutin, isoquercetrin and 3'-OH-genkwanin. All compounds, tested at concentrations ranging between 10(-5) and 10(-7) M, showed stimulatory activities.

Thermoanalytical study and characterization of native starches of Paraná pine seeds (Araucaria angustiofolia, Bert O. Ktze) and European chestnut seeds (Castanea sativa, Mill)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeitos alelopáticos de microcistinas em rúcula (Eruca sativa Mill.)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Estudo de biorremediação dos azo corantes têxteis Acid Blue 161 e Procion Red MX-5B por fungos filamentosos em solução simples e solução binária associado a testes de toxicidade com Lactuca sativa e Artemia salina

Pós-graduação em Ciências Biológicas (Microbiologia Aplicada) - IBRC

Efeito de extratos de adubos verdes sobre Lactuca sativa e Digitaria horizontalis

Objetivou-se avaliar os efeitos de extratos de quatro espécies de adubos verdes (Canavalia ensiformis, Crotalaria spectabilis, Mucuna aterrimae Sorghum bicolor cv. AG 2005) sobre a germinação de sementes e o crescimento inicial de plântulas deLactuca sativa e de Digitaria horizontalis. Foram realizados dois experimentos: no primeiro, avaliou-se a aplicação das soluções diluídas a 1%, 2%, 3%, 4%, 5% e10% de extratos aquosos da parte aérea e das raízes das espécies de adubos verdes sobre a germinação, índice de velocidade de germinação e o comprimento radicular de L. sativa; no segundo, avaliou-se a incorporação ao solo de 0, 10, 20, 30, 40 e 50 g dm-3 da biomassa dos adubos verdes sobre o acúmulo de massa seca (parte aérea e raízes) e o desenvolvimento radicular de plântulas de L. sativa e de D. horizontalis. Concluiu-se que os extratos aquosos das espécies C. ensiformis, C. spectabilis, M. aterrima e S. bicolor cv. AG 2005 promoveram efeitos negativos sobre a germinação e o IVG das sementes de L. sativa. A incorporação ao solo da biomassa dessas espécies de adubos verdes influenciou negativamente no desenvolvimento inicial das plântulas de L. sativa. Entretanto, verificou-se efeito positivo sobre o desenvolvimento inicial de D. horizontalis com a incorporação ao solo da biomassa de C. spectabilis.

Modulation of L-α-lysophosphatidylinositol/GPR55 mitogen-activated protein kinase (MAPK) signaling by cannabinoids

GPR55 is activated by l-α-lysophosphatidylinositol (LPI) but also by certain cannabinoids. In this study, we investigated the GPR55 pharmacology of various cannabinoids, including analogues of the CB1 receptor antagonist Rimonabant®, CB2 receptor agonists, and Cannabis sativa constituents. To test ERK1/2 phosphorylation, a primary downstream signaling pathway that conveys LPI-induced activation of GPR55, a high throughput system, was established using the AlphaScreen® SureFire® assay. Here, we show that CB1 receptor antagonists can act both as agonists alone and as inhibitors of LPI signaling under the same assay conditions. This study clarifies the controversy surrounding the GPR55-mediated actions of SR141716A; some reports indicate the compound to be an agonist and some report antagonism. In contrast, we report that the CB2 ligand GW405833 behaves as a partial agonist of GPR55 alone and enhances LPI signaling. GPR55 has been implicated in pain transmission, and thus our results suggest that this receptor may be responsible for some of the antinociceptive actions of certain CB2 receptor ligands. The phytocannabinoids Δ9-tetrahydrocannabivarin, cannabidivarin, and cannabigerovarin are also potent inhibitors of LPI. These Cannabis sativa constituents may represent novel therapeutics targeting GPR55.

The role of human-induced fire and sweet chestnut (Castanea sativa Mill.) cultivation on the long-term landscape dynamics of the southern Swiss Alps

Changes in fire occurrence during the last decades in the southern Swiss Alps make knowledge on fire history essential to understand future evolution of the ecosystem composition and functioning. In this context, palaeoecology provides useful insights into processes operating at decadal-to-millennial time scales, such as the response of plant communities to intensified fire disturbances during periods of cultural change. We provide a high-resolution macroscopic charcoal and pollen series from Guèr, a well-dated peat sequence at mid-elevation (832 m.a.s.l.) in southern Switzerland, where the presence of local settlements is documented since the late Bronze Age and the Iron Age. Quantitative fire reconstruction shows that fire activity sharply increased from the Neolithic period (1–3 episodes/1000 year) to the late Bronze and Iron Age (7–9 episodes/1000 year), leading to extensive clearance of the former mixed deciduous forest (Alnus glutinosa, Betula, deciduous Quercus). The increase in anthropogenic pollen indicators (e.g. Cerealia-type, Plantago lanceolata) together with macroscopic charcoal suggests anthropogenic rather than climatic forcing as the main cause of the observed vegetation shift. Fire and controlled burning were extensively used during the late Roman Times and early Middle Ages to promote the introduction and establishment of chestnut (Castanea sativa) stands, which provided an important wood and food supply. Fire occurrence declined markedly (from 9 to 5–6 episodes/1000 year) during late Middle Ages because of fire suppression, biomass removal by human population, and landscape fragmentation. Land-abandonment during the last decades allowed forest to partly re-expand (mainly Alnus glutinosa, Betula) and fire frequency to increase.