Valeria Bregola

Lunasin in wheat: A chemical and molecular study on its presence or absence

Lunasin is a peptide whose anticancer properties are widely reported. Originally isolated from soybean seeds, lunasin was also found in cereal (wheat, rye, barley and Triticale), Solanum and amaranthus seeds. However, it was recently reported that searches of transcript and DNA sequence databases for wheat and other cereals failed to identify sequences with similarity to those encoding the lunasin peptide in soy. In order to clarify the presence or absence of lunasin in wheat varieties, a broad investigation based on chemical (LC-ESI-MS) and molecular (PCR) analyses was conducted. Both approaches pointed out the absence of lunasin in the investigated wheat genotypes; in particular no compounds with a molecular weight similar to that of lunasin standard and no lunasin-related sequences were found in the analysed wheat samples. These findings confirm the hypothesis, reported in recent researches, that lunasin is not a wheat-derived peptide.

Transcriptome Profiling of Wheat Seedlings following Treatment with Ultrahigh Diluted Arsenic Trioxide

Plant systems are useful research tools to address basic questions in homeopathy as they make it possible to overcome some of the drawbacks encountered in clinical trials (placebo effect, ethical issues, duration of the experiment, and high costs). The objective of the present study was to test the hypothesis whether 7-day-old wheat seedlings, grown from seeds either poisoned with a sublethal dose of As2O3 or unpoisoned, showed different significant gene expression profiles after the application of ultrahigh diluted As2O3 (beyond Avogadros limit) compared to water (control). The results provided evidence for a strong gene modulating effect of ultrahigh diluted As2O3 in seedlings grown from poisoned seeds: a massive reduction of gene expression levels to values comparable to those of the control group was observed for several functional classes of genes. A plausible hypothesis is that ultrahigh diluted As2O3 treatment induced a reequilibration of those genes that were upregulated during the oxidative stress by bringing the expression levels closer to the basal levels normally occurring in the control plants.

Determination of phenolic compounds in ancient and modern durum wheat genotypes

Due to its significant amount of antioxidants, durum wheat (Triticum turgidum ssp. durum) could potentially contribute to the protection against a number of chronic diseases, such as diabetes, cardiovascular disease, and cancer. The increasing interest toward healthy food among both consumers and scientists has moved the focus toward the phytochemical content of whole wheat grains. The aim of this study was to identify the phytochemical composition of 22 cultivars belonging to old and modern durum wheat genotypes, including antioxidant capacity (DPPH and FRAP tests). In addition, five phenolic acids involved in the vanillin biosynthesis pathway and in the defence mechanism of plants were screened using UHPLC‐MS/MS. Remarkable quantitative differences in the amount of the five phenolic acids analysed (p < 0.05) were detected among the wheat genotypes investigated. Results showed that among the investigated phenolic compounds, trans‐ferulic acid was the most abundant, ranging from 13.28 to 324.69 μg/g; all the other identified compounds were present at lower concentrations. Moreover, significant differences on the antioxidant activity were observed. Collected data suggested possible differences between biosynthetic pathway of secondary metabolites among durum wheat genotypes.

Isolation and Characterization of Wheat Derived Nonspecific Lipid Transfer Protein 2 (nsLTP2): Characterization of nsLTP2 peptide…

Numerous studies support the protective role of bioactive peptides against cardiovascular diseases. Cereals represent the primary source of carbohydrates, but they also contain substantial amounts of proteins, therefore representing a potential dietary source of bioactive peptides with nutraceutical activities. The analysis of wheat extracts purified by chromatographic techniques by means of HPLC-UV/nanoLC-nanoESI-QTOF allowed the identification of a signal of about 7 kDa which, following data base searches, was ascribed to a nonspecific lipid-transfer protein (nsLTP) type 2 from Triticum aestivum (sequence coverage of 92%). For the first time nsLTP2 biological activities have been investigated. In particular, in experiments with human umbilical vein endothelial cells (HUVEC), nsLTP2 displayed antioxidant and cytoprotective activities, being able to significantly decrease reactive oxygen species (ROS) levels and to reduce lactate dehydrogenase (LDH) release, generated following oxidative (hydrogen peroxide) and inflammatory (tumor necrosis factor α, interleukin-1β, and lipopolysaccharide) stimulation. The obtained promising results suggest potential protective role of nsLTP2 in vascular diseases prevention. PRACTICAL APPLICATION: nsLTP 2 peptide is resistant to proteases throughout the gastrointestinal tract and exerts antioxidant and cytoprotective activities. These characteristics could be exploited in vascular diseases prevention.

Differentiation of modern and ancient varieties of common wheat by quantitative capillary electrophoretic profile of phenolic acids

Phenolic compounds have received great attention among the health promoting phytochemicals in common wheat (Triticum aestivum L.), mainly because of their strong antioxidant properties. In the present study a simple Capillary Zone Electrophoresis (CZE) method with UV detection was optimized and validated for the quantitation of six of the most important phenolic acids in whole grain i.e., sinapic, ferulic, syringic, p-coumaric, vanillic and p-hydroxybenzoic acid. The separation was achieved in a running buffer composed of sodium phosphate solution (50 mM) in water/methanol 80:20 (v/v) at pH 6.0 and using a fused-silica capillary at the temperature of 30 °C under application of 27 kV. By means of diode array detector, and made possible by the favorable characteristic UV spectra, the quantitation of the solutes was carried out at 200, 220 and 300 nm, in the complex matrices represented by the soluble and bound fractions of wheat flours. The validation parameters of the method i.e., linearity, sensitivity, precision, accuracy and robustness were in line with those obtained by consolidated separation techniques applied for the same purposes (e.g., HPLC-UV), with a significant advantage in term of analysis time (less than 12 min). Ten varieties of soft wheat (five modern Italian and five old Italian genotypes) were analysed and the data were subjected to Principal Components Analysis (PCA). Interestingly, significant differences of the quantitative phenolic acids profile were observed between the modern and the ancient genotypes, with the latter showing higher amount of the main represented phenolic acids.