Untargeted Metabolomic Analysis of Capsicum spp. by GC-MS.

INTRODUCTION: In order to conserve the biodiversity of Capsicum species and find genotypes with potential to be utilised commercially, Embrapa Clima Temperado maintains an active germplasm collection (AGC) that requires characterisation, enabling genotype selection and support for breeding programmes. OBJECTIVE: The objective of this study was to characterise pepper accessions from the Embrapa Clima Temperado AGC and differentiate species based on their metabolic profile using an untargeted metabolomics approach. MATERIAL AND METHODS: Cold (-20°C) methanol extraction residue of freeze-dried fruit samples was partitioned into water/methanol (A) and chloroform (B) fractions. The polar fraction (A) was derivatised and both fractions (A and B) were analysed by gas chromatography coupled to mass spectrometry (GC-MS). Data from each fraction was analysed using a multivariate principal component analysis (PCA) with XCMS software. RESULTS: Amino acids, sugars, organic acids, capsaicinoids, and hydrocarbons were identified. Outlying accessions including P116 (C. chinense), P46, and P76 (C. annuum) were observed in a PCA plot mainly due to their high sucrose and fructose contents. PCA also indicated a separation of P221 (C. annuum) and P200 (C. chinense), because of their high dihydrocapsaicin content. CONCLUSIONS: Although the metabolic profiling did not allow for grouping by species, it permitted the simultaneous identification and quantification of several compounds complementing and expanding the metabolic database of the studied Capsicum spp. in the AGC. Copyright © 2017 John Wiley & Sons, Ltd.

Understanding drought response mechanisms in wheat and multi-trait selection.

Wheat crop is very sensitive to osmotic stress conditions. As an abiotic stress, drought may exert a considerable effect on the levels of specialized metabolites in plants. These metabolites may exert beneficial biological activities in the prevention or treatment of disorders linked to oxidative stress in plants and humans. Furthermore, osmoprotector accumulation helps wheat to increase the maintenance of osmotic balance. Therefore, identifying wheat genotypes with better drought tolerance is extremely important. In this sense, this research aimed to understand agronomic, physiological and biochemical responses of spring wheat strains and cultivars to drought stress, under field conditions, and jointly select strains via multi-trait index. We evaluated agronomic, physiological and biochemical variables in 18 genotypes under field condition. The results demonstrated that all variables were affected by the drought. Most genotypes were significantly reduced in grain yield, except VI_14774, VI_14668, VI_9007 and TBIO_ATON. The variables related to photosynthesis were also affected. An increase above 800% was observed in proline contents in genotypes under drought. Sodium and potassium also increased, mainly for VI_131313 (Na), while VI_130758 and VI_14774 presented increased K. We evaluated the antioxidant potential of the different strains and the total content of phenolic compounds. The most drought-responsive genotypes were BRS_264, VI_14050 and VI_14426. Reduced grain yield and photosynthetic variables, and increased specialized metabolism compounds are due to plant defense mechanisms against drought conditions. Furthermore, variation in genotypes can be explained by the fact that each plant presents a different defense and tolerance mechanism, which may also occur between genotypes of the same species. Four strains were selected by the multivariate index: VI_14055, VI_14001, VI_14426 and VI_1466. Such results allow us to predict which genotype(s) performed best in semi-arid environments and under climatic fluctuations.

Metabolic profile of olive leaves of different cultivars and collection times.

Due to the appreciable amounts of bioactive compounds in olive leaves and the effect of abiotic stresses on their synthesis, this study evaluated the metabolic profile of leaves of olive cultivars (Arbequina, Manzanilla and Picual) collected in four periods of the year (autumn, winter, spring and summer). The determination of the profile of bioactive compounds (phenolic compounds, flavonoids, tannins, carotenoids and chlorophylls) by spectrophotometry and the individual compounds by liquid chromatography coupled to mass spectrum, as well as antioxidant potential tests were performed. As results it was possible to observe that the leaves of the cultivar Manzanilla presented the highest levels of phenolic compounds and that the leaves collected in the summer presented a number of compounds much more relevant than the others. Thus, it was possible to conclude that the cultivar and the collection season significantly affect the bioactive content and the antioxidant potential of olive leaves.

Mineral and Fatty Acid Content Variation in White Oat Genotypes Grown in Brazil.

A healthy diet is directly associated with a nutrient-rich and toxic contaminant poor intake. A diet poor in diversity can lead to micronutrient deficiency. The intake of functional foods can provide benefits in the prevention and treatment of diseases. Oats are a functional food; are a source of soluble fiber, lipids, proteins, vitamins, minerals, and polyphenols; and are low in carbohydrate content. Thus, in this study, we characterize mineral accumulation, fatty acid composition, and the absence of contaminants in oat genotypes to evaluate the potential of this cereal as food to minimize the effects of micronutrient deficiency. Most of the oat genotypes showed higher mineral levels than other cereals such as wheat, rice, and maize. FAEM 5 Chiarasul, Barbarasul, UPFA Ouro, URS Altiva, URS Brava, and URS Taura showed higher iron concentration while URS Brava showed the highest zinc concentration. The oat genotypes did not show significant arsenic, strontium, and cadmium accumulation. Considering the accumulation of trace elements in the grain, little genetic diversity among the analyzed oat accessions was detected, dividing into two groups. Regarding fatty acid composition, IPR Afrodite, FAEM 4 Carlasul, FAEM 5 Chiarasul, URS Taura, Barbarasul, and URS 21 showed higher essential fatty acid concentrations. These genotypes can be used in crosses with URS Brava, which displayed a higher Fe and Zn accumulation and is genetically distant from the other cultivars. Oat is a functional food showing ability for the accumulation of minerals and also essential fatty acids.