Effect of Agroecological Conditions on Biologically Active Compounds and Metabolome in Carrot.

Carrot serves as a source of health-beneficial phytochemicals for human diet whose content is affected by agroecological conditions. The effect of conventional, integrated and organic farming on ascorbic acid (AA) and α,ß-carotene levels of new carrot cultivars Cortina F1 and Afalon F1 was investigated and their metabolomic profiles were measured by direct analysis in real time ion source coupled with a high-resolution mass spectrometer (DART-HRMS). Cortina and Afalon exhibited high levels of AA and total carotenes under all agroecological conditions tested that fluctuated in broad ranges of 215-539 and 173-456 mg AA.kg-1 dry biomass and 1069-2165 and 1683-2165 mg carotene.kg-1 dry biomass, respectively. The ratio of ß- to α-carotene in both cultivars was about 1.3. The most important variable for the PCA and the partial least squares discriminant analysis (PLS-DA) models for ethyl acetate extracts measured in positive and negative ionization mode was 6-methoxymellein (6-MM). Total carotene content and 6-MM levels were higher in the organic carrot compared to the conventional one and were correlated with a higher level of spontaneous infection. Other important compounds identified were sitosterol, hexose and various organic acids including antioxidant ferulic and coumaric acids. The findings allow comparison of metabolomic profiles and the AA and carotene contents of both cultivars with those of other commercially used carrots.

Assessment of rosehips based on the content of their biologically active compounds.

In this study, an in-depth analysis of the unique set of rosehip samples from 71 Rosa genotypes was conducted with the aim to identify the most suitable ones for applications in the food and pharmaceutical industries based on the content of biologically active compounds. In the first part of our experiments, the antioxidant activity was determined by 2,2-diphenyl-1-picrylhydrazyl assay and the genotypes with the highest values were selected for the follow-up analysis. In the second part of experiments, the major classes of biologically active compounds in rosehips such as carotenoids, tocopherols, flavonoids, and triterpenoic acids were further quantified using liquid chromatography-based techniques. Large variation was observed among all the analyzed compounds with intraspecific variation often hiding interspecific or intersectional differences. The compounds studied herein thus do not provide a sharp tool for chemotaxonomic resolution of the genus Rosa. High intraspecific variation indicates the necessity to screen and utilize individual rose genotypes rather than representatives of the species when searching for sources of biologically active compounds. In the final stage of the study, 10 genotypes were selected for further cultivation and use, based on the highest concentrations of the analyzed biologically active compounds.

Origin authentication of distillers' dried grains and solubles (DDGS)--application and comparison of different analytical strategies.

In the context of products from certain regions or countries being banned because of an identified or non-identified hazard, proof of geographical origin is essential with regard to feed and food safety issues. Usually, the product labeling of an affected feed lot shows origin, and the paper documentation shows traceability. Incorrect product labeling is common in embargo situations, however, and alternative analytical strategies for controlling feed authenticity are therefore needed. In this study, distillers' dried grains and solubles (DDGS) were chosen as the product on which to base a comparison of analytical strategies aimed at identifying the most appropriate one. Various analytical techniques were investigated for their ability to authenticate DDGS, including spectroscopic and spectrometric techniques combined with multivariate data analysis, as well as proven techniques for authenticating food, such as DNA analysis and stable isotope ratio analysis. An external validation procedure (called the system challenge) was used to analyze sample sets blind and to compare analytical techniques. All the techniques were adapted so as to be applicable to the DDGS matrix. They produced positive results in determining the botanical origin of DDGS (corn vs. wheat), and several of them were able to determine the geographical origin of the DDGS in the sample set. The maintenance and extension of the databanks generated in this study through the analysis of new authentic samples from a single location are essential in order to monitor developments and processing that could affect authentication.

Phospholipase D affects translocation of NPR1 to the nucleus in Arabidopsis thaliana.

Phytohormone salicylic acid (SA) is a crucial component of plant-induced defense against biotrophic pathogens. Although the key players of the SA pathway are known, there are still gaps in the understanding of the molecular mechanism and the regulation of particular steps. In our previous research, we showed in Arabidopsis suspension cells that n-butanol, which specifically modulates phospholipase D activity, significantly suppresses the transcription of the pathogenesis related (PR-1) gene, which is generally accepted as the SA pathway marker. In the presented study, we have investigated the site of n-butanol action in the SA pathway. We were able to show in Arabidopsis plants treated with SA that n-butanol inhibits the transcription of defense genes (PR-1, WRKY38). Fluorescence microscopy of Arabidopsis thaliana mutants expressing 35S::NPR1-GFP (nonexpressor pathogenesis related 1) revealed significantly decreased nuclear localization of NPR1 in the presence of n-butanol. On the other hand, n-butanol did not decrease the nuclear localization of NPR1 in 35S::npr1C82A-GFP and 35S::npr1C216A-GFP mutants constitutively expressing NPR1 monomers. Mass spectrometric analysis of plant extracts showed that n-butanol significantly changes the metabolic fingerprinting while t-butanol had no effect. We found groups of the plant metabolites, influenced differently by SA and n-butanol treatment. Thus, we proposed several metabolites as markers for n-butanol action.