Comparative evaluation of total antioxidant capacities of plant polyphenols.

Thirty‐seven samples of naturally occurring phenolic compounds were evaluated using three common in vitro assays for total antioxidant activity (TAC) testing: the Trolox Equivalent Antioxidant Capacity (TEAC), the Ferric Reducing Antioxidant Potential (FRAP) and the 2,2‐ diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging assay, in addition to the Folin‐Ciocalteu reagent reactivity (FCR). We found that antioxidant hierarchies depended on the choice of assay and applied ANOVA analyses to explore underlying structure‐TAC dependencies. In addition tostatistically confirming the empirically established connection between flavonoid ring‐B catechol and high TEAC or FRAP, new correlations were also found. In flavonoids, (i) hydroxyl groups on ring‐B had a positive effect on all four TAC assays; (ii) the presence of a 3‐hydroxyl group on ring‐C increased TEAC and FRAP, but had no effect on DPPH or FCR; (iii) Phenolic acids lacking a 3‐hydroxyl group had significantly lower FRAP or DPPH than compounds having this structure, while TEAC or FCR were not affected. Results demonstrated that any TAC‐based ranking of phenolic rich samples would very much depend on the choice of assay, and argue for use of more than one technique. As an illustration, we compared results of the above four assays using either grapevine leaf extracts or synthetic mixtures of compounds prepared according to major polyphenols identified in the leaves

Importance of antixenosis and antibiosis resistance to the cabbage whitefly (Aleyrodes proletella) in brussels sprout cultivars

The cabbage whitefly Aleyrodes proletella (L.) (Hemiptera: Aleyrodidae) is an important pest of a wide range of vegetable Brassicas. Since the control of this pest is still challenging, new approaches such as the use of resistant cultivars are required. For this, we screened 16 commercialised Brussels sprout cultivars for resistance against this species. Antibiosis was tested with no-choice experiments in a climate chamber, using reproduction, mortality, longevity, developmental time and weight as parameters. Antixenosis was screened in three choice experiments with circular design in a greenhouse to detect cultivar preferences. A field trial with both antibiosis and antixenosis tests was done to verify results under natural conditions. Finally, for several cultivars, also the leaf glucosinolate concentrations were analysed. Cabbage whiteflies showed on certain cultivars significantly increased mortality, prolonged developmental times and reduced weights. Besides, some cultivars were significantly less infested. However, the incidence of antibiosis and antixenosis as well as the glucosinolate patterns were partly inconsistent. Although a number of moderately resistant cultivars could be identified, the detected resistance is certainly not strong and consistent enough as an exclusive measure of a plant protection strategy but might become a component of a multi-layered strategy against cabbage whiteflies

Trends Shaping Western European Agrifood Systems of the Future

Western Europe’s agrifood systems are highly developed, extremely complex, and dependably produce food for billions. Securing their functionality is imperative whilst dealing with varieties of major challenges and opportunities in the future. Multiple stakeholders are involved in system transitions; therefore, synthesizing views from different scientific disciplines is essential for a robust trend analysis. Through workshops with a variety of experts, extensive research, followed by close monitoring over 5 years, we identified trends that will influence the shape of the evolving agrifood systems. Based on this, we determined which trends need addressing by agrifood research to secure the system’s future functioning. We detected nine trends with 50 sub-topics that will shape the future of Western European agrifood systems, of which 5 are classified as macro- and 4 as micro-trends. Our second objective was to improve the efforts of the stakeholders in- and outside of the agrifood area to secure functioning and further improvement through giving a comprehensive overview. This contributes to enhanced strategies for sustainable and resilient agrifood systems that produce sufficient affordable nutritious food for a planetary health diet, and hence, supporting successful implementation of selected goals from the 2030 Agenda for Sustainable Development and the European Green Deal

Survey of bioactive metabolites in selected cultivars and varieties of Lactuca sativa L. under water stress

Plants respond to water stress with a variety of physiological and biochemical changes, but their response vary between species, varieties and cultivars. The present study focused on changes of bio-functional phytochemicals (phenolic compounds, chlorophyll, carotenoids, dietary fiber) in commercial cultivars and old, traditional varieties of lettuce under different water regimes (water-deficit, well-watered and water-logged).Results revealed lettuce varieties and cultivars with a different response behavior to water stress. Biomass production under drought conditions was reduced significantly. Carotenoid and chlorophyll contents decreased in both water extremes, while total phenols were accumulated under limited water availability. Dietary fiber content was not influenced by different water regimes. Water stress reduces biomass production and led to a change of phytochemicals in lettuce, however, old and traditional varieties did not show a different water stress adaptation compared to commercial cultivars

CO2 treatment increases glucosinolate hydrolysis products in two Arabidopsis thaliana accessions

Brassicales include many vegetables of nutritional interest because the hydrolysis products of their phytochemicals, the glucosinolates, have health-promoting properties. So far, the impact of rising CO2 concentrations on glucosinolates and their hydrolysis is unclear. Applying a modified atmosphere, we exposed two Arabidopsis thaliana accessions that differ in their glucosinolate hydrolysis behavior, namely Hi-0 and Bur-0, to elevated CO2 concentrations. Glucosinolates and their hydrolysis products were analyzed using UHPLC-DAD-MS and GC-MS. CO2 treatment increased indicators of primary production, such as biomass, leaf area and electron transport rate, and increased gluco-sinolate levels in Bur-0, but not Hi-0. Significantly, released glucosinolate hydrolysis product levels increased by up to 122% in Bur-0 due to increased epithionitrile formation. Likewise, in Hi-0 glucosinolate hydrolysis product levels increased after CO2 treatment by up to 67%, caused by enhanced nitrile and to some extent isothiocyanate formation. In addition, more alkenyl rather than alkyl glucosinolates were formed in Bur-0 under elevated CO2, thus changing the glucosinolate profile compositions. As CO2 treatment enhanced primary production but also overall glucosinolate hydrolysis pro-duct formation, it is conceivable to recycle excess CO2 by using it as supplement greenhouse gas to produce high-quality food

The interaction of salinity and light regime modulates photosynthetic pigment content in edible halophytes in greenhouse and indoor farming

Given its limited land and water use and the changing climate conditions, indoor farming of halophytes has a high potential to contribute significantly to global agriculture in the future. Notably, indoor farming and classical greenhouse cultivation differ in their light regime between artificial and solar lighting, which can influence plant metabolism, but how this affects the cultivation of halophytes has not yet been investigated. To address this question, we studied the yield and content of abscisic acid, carotenoids, and chlorophylls as well as chloride of three halophyte species (Cochlearia officinalis, Atriplex hortensis, and Salicornia europaea) differing in their salt tolerance mechanisms and following four salt treatments (no salt to 600 mM of NaCl) in two light regimes (greenhouse/indoor farming). In particular, salt treatment had a strong influence on chloride accumulation which is only slightly modified by the light regime. Moreover, fresh and dry mass was influenced by the light regime and salinity. Pigments exhibited different responses to salt treatment and light regime, reflecting their differing functions in the photosynthetic apparatus. We conclude that the interaction of light regime and salt treatment modulates the content of photosynthetic pigments. Our study highlights the potential applications of the cultivation of halophytes for indoor farming and underlines that it is a promising production system, which provides food alternatives for future diets

Effect of Narrowband UV-B Irradiation on the Growth Performance of House Crickets

Indoor co-cultivation systems can answer to the need for sustainable and resilient food production systems. Rearing organisms under light-emitting diodes (LEDs) irradiation provides the possibility to control and shape the emitted light spectra. UV-B-irradiation (280–315 nm) can positively affect the nutritional composition of different plants and other organisms, whereas information on edible insects is scarce. To evaluate the potential effect of the photosynthetically active radiation (PAR) and LED-emitting LEDs on the rearing and nutritional quality of edible insects, house crickets (Acheta domesticus) were reared from the age of 21 days under controlled LED spectra, with an additional UV-B (0.08 W/m2) dose of 1.15 KJm2 d−1 (illuminated over a period for 4 h per day) for 34 days. UV-B exposure showed no harm to the weight of the crickets and significantly increased their survival by ca. 10% under narrowband UV-B treatment. The nutritional composition including proteins, fat and chitin contents of the insects was not affected by the UV-B light and reached values of 60.03 ± 10.41, 22.38 ± 2.12 and 9.33 ± 1.21%, respectively, under the LED irradiation. Therefore, house crickets can grow under LED irradiation with a positive effect of narrowband UV-B application on their survival

Biologische Bodenentseuchung für eine umweltgerechte und intensive Gehölzproduktion

Der wiederholte Nachbau von Gehölzen der Familie der Rosaceae führt zu einer Nachbaukrankheit, die als Bodenmüdigkeit beschrieben wird. Eine wirksame Bekämpfung der Bodenmüdigkeit war die chemische Desinfektion mit Basamid® Granulat, basierend auf der Freisetzung eines Isothiocyanates (ITC). Die Zulassung von Basamid® Granulat ist in Deutschland abgelaufen. Eine Alternative könnte die Biofumigation darstellen. Bei der Biofumigation werden Glucosinolat(GS)-haltige Pflanzenteile von Vertretern der Brassicaceae in den Boden eingearbeitet. Die toxischen GS-Abbauprodukte, vor allem ITC, führen zu einer biologischen Bodendesinfektion. In dem berichteten Projekt wurde die Wirkung der ein- und zweijährigen Biofumigation von Brassica juncea und Raphanus sativus mit dem Anbau von Tagetes patula NEMAMIX, der Anwendung von Basamid® Granulat und des fortgesetzten Nachbaus der Indikatorpflanzen Malus sylvestris ‘Bittenfelder, Malus M4 bzw. M106 und Rosa corymbifera ‘Laxa’ verglichen. Das beste Wachstum der Indikatorpflanzen erbrachte ein vorausgegangener, zweijähriger Anbau von Tagetes patula NEMAMIX. Die praxisübliche Anwendung von Basamid® Granulat zeigte wenig Wirkung. Vermutlich war der Boden zum Anwendungstermin zu trocken. Eine geringe Wirkung erbrachte auch die ein- oder auch zweijährige Biofumigation mit Brassica juncea und Raphanus sativus. Auch die im Rahmen der Projektverlängerung zusätzlich geprüfte Einarbeitung von Brassica juncea-Samenmehl, die Verwendung der speziellen Saatgutmischung viterra®BIOFUMIGATION zur klassischen Biofumigation sowie die Dämpfung des Bodens mit Hilfe des CombiMIXERs an zwei nachbaukranken Baumschulstandorten brachten nicht die erhofften positive Effekte auf das Pflanzenwachstum der Indikatorpflanzen. Wieder war die einjährige Kultur von Tagetes die erfolgreichste Var. im Vergleich zum unbehandelten nachbaukranken Boden. Es konnten nur wenig positive Effekte auf das Wachstum der Indikatorpflanzen statistisch gesichert werden. Selbst in den Fällen, in denen signifikante Unterschiede auftraten, reichten diese Effekte aus Sicht der Praxis bei weitem nicht aus, um die durch Minderwuchs entstehenden Ertragsverluste auszugleichen. Mögliche Gründe für die schlechte Wirkung der geprüften Varianten werden diskutiert

Chemical composition of field grown radish (Raphanus sativus L. var. sativus) as influenced by season and moderately reduced water supply

Seasonal variations in water availability as increasingly provoked by climate change pose severe challenges for vegetable production, particularly for crops requiring reliable and high water supply for achieving satisfactory quality. In contrast to most previous studies applying severe water deficits, we examined the effects of moderate water deficits on the chemical composition of red radish roots during three consecutive years with variable climatic conditions. Radish were cultivated in open field, applying two different water supply treatments and following a randomized block design comprising four sets of six plots each. The resulting water reductions of 3-20 % led to a significant increase of dry matter-based myo-inositol levels, whereas those of selected minerals and trace elements, phenolics and glucosinolates decreased. Anthocyanin levels remained unchanged. Fresh-matter related levels of most analytes increased upon reduced water treatments due to higher dry matter contents. While pigment levels in radish remained unchanged, mild water deficit affected other quality-related parameters such as pungency-related glucosinolates

Benzylglucosinolate Derived Isothiocyanate from Tropaeolum majus Reduces Gluconeogenic Gene and Protein Expression in Human Cells

Nasturtium (Tropaeolum majus L.) contains high concentrations of benzylglcosinolate. We found that a hydrolysis product of benzyl glucosinolate—the benzyl isothiocyanate (BITC)—modulates the intracellular localization of the transcription factor Forkhead box O 1 (FOXO1). FoxO transcription factors can antagonize insulin effects and trigger a variety of cellular processes involved in tumor suppression, longevity, development and metabolism. The current study evaluated the ability of BITC—extracted as intact glucosinolate from nasturtium and hydrolyzed with myrosinase—to modulate i) the insulin-signaling pathway, ii) the intracellular localization of FOXO1 and, iii) the expression of proteins involved in gluconeogenesis, antioxidant response and detoxification. Stably transfected human osteosarcoma cells (U-2 OS) with constitutive expression of FOXO1 protein labeled with GFP (green fluorescent protein) were used to evaluate the effect of BITC on FOXO1. Human hepatoma HepG2 cell cultures were selected to evaluate the effect on gluconeogenic, antioxidant and detoxification genes and protein expression. BITC reduced the phosphorylation of protein kinase B (AKT/PKB) and FOXO1; promoted FOXO1 translocation from cytoplasm into the nucleus antagonizing the insulin effect; was able to down-regulate the gene and protein expression of gluconeogenic enzymes; and induced the gene expression of antioxidant and detoxification enzymes. Knockdown analyses with specific siRNAs showed that the expression of gluconeogenic genes was dependent on nuclear factor (erythroid derived)-like2 (NRF2) and independent of FOXO1, AKT and NAD- dependent deacetylase sirtuin-1 (SIRT1). The current study provides evidence that BITC might have a role in type 2 diabetes T2D by reducing hepatic glucose production and increasing antioxidant resistance