Stefano Benedettelli

Determination of phenolic compounds in modern and old varieties of durum wheat using liquid chromatography coupled with time-of-flight mass spectrometry.

An evaluation of the grain functional components of Italian durum wheat cultivars was conducted. The raw material was obtained from the field trial performed in 2006-2007 at the Experimental Farm of the University of Bologna, (Bologna, Italy). The aim of this study was to define the phytochemical profile of ten varieties, comprised of old and modern durum wheat genotypes, including quantitative and qualitative phenolic and flavonoid content (free and bound forms). The results showed that mean values of total phenolic compound and total flavonoid content in old wheat varieties (878.2+/-19.0 micromol gallic acid equivalent/100g of grain and 122.6+/-25.4 micromol catechin equivalent/100g of grain, respectively) did not differ significantly from those detected in modern genotypes (865.9+/-128.9 micromol gallic acid equivalent/100g and 123.5+/-20.6 micromol catechin equivalent/100g, respectively). However, the HPLC-ESI-TOF-MS analysis highlighted remarkable differences between modern and old cultivars. The interpretation of the mass spectra allowed the identification of 70 phenolic compounds, including coumarins, phenolic acids, anthocyanins, flavones, isoflavones, proanthocyanidins, stilbenes and lignans. The free extracts of ancient wheat varieties showed the presence of a mean number of phenolic compounds and isomer forms (8.7+/-2.5 and 7.7+/-4.7 respectively) significantly higher than in modern genotypes (4.4+/-2.9 and 2.0+/-2.4, respectively). A similar trend was observed also for the bound phenolic fraction. Moreover, the phytochemical profiles showed the presence of unique phenolic compounds in both free and bound fractions of some of the investigated wheat genotypes. Results highlighted that investigated old wheat cultivars may offer unique nutraceutical values for their peculiar contents in bioactive phytochemicals, suggesting their uses into a wide range of regular and specialty products naturally enriched with health-promoting compounds.

Storage-protein variation in wild emmer wheat (Triticum turgidum ssp.dicoccoides) from Jordan and Turkey. I. Electrophoretic characterization of genotypes.

Seed storage-protein variation at theGlu-A1,Glu-B1 andGli-B1/Glu-B3 loci in the tetraploid wild progenitor of wheat,T. dicoccoides, was studied electrophoretically in 315 individuals representing nine populations from Jordan and three from Turkey. A total of 44 different HMW-glutenin patterns were identified, resulting from the combination of 15 alleles in the A genome and 19 in the B genome. Twenty-seven new allelic variants, 12 at theGlu-A1 locus and 15 at theGlu-B1 locus, were identified by comparing the mobilities of their subunits to those previously found in bread and durum wheats. The novel variants include six alleles at theGlu-A1 locus showing both x and y subunits. The genes coding for the 1Bx and 1By subunits showed no or very little (3%) inactivity, the 1Ax gene showed a moderate degree (6.3%) of inactivity whereas the gene coding for lAy showed the highest degree of inactivity (84.8%). A high level of polymorphism was also present for the omega- and gamma-gliadins and LMW-glutenin subunits encoded by genes at the linkedGli-B1 andGlu-B3 loci (19 alleles). Some Jordanian accessions were found to contain omega-gliadin 35, gamma-gliadin 45, and LMW-2 also present in cultivated durum wheats and related to good gluten viscoelasticity. The newly-discovered alleles enhance the genetic variability available for improving the technological quality of wheats. Additionally some of them may facilitate basic research on the relationship between industrial properties and the number and functionality of HMW- and LMW-glutenin subunits.

Characterization of Khorasan wheat (Kamut) and impact of a replacement diet on cardiovascular risk factors: cross-over dietary intervention study

Background/Objectives:Khorasan wheat (Kamut) is an ancient grain with widely acclaimed beneficial effects on human health. The objective was to characterise Kamut and to examine the effect of a replacement diet with their products on cardiovascular risk parameters.Subjects/Methods:We conducted a randomized, single-blinded cross-over trial with two intervention phases on 22 healthy subjects (14 females; 8 males). The participants were assigned to consume products (bread, pasta and crackers) made either from Kamut or control semi-whole-grain wheat for 8 weeks in a random order. An 8-week washout period was implemented between the interventions. Laboratory analyses were performed both at the beginning and at the end of each intervention phase.Results:At a general linear model for repeated measurements adjusted for several confounders, consumption of Kamut products showed a significant reduction of metabolic risk factors such as total cholesterol (mean reduction: −8.46 mg/dl; −4%), low-density lipoprotein cholesterol (−9.82 mg/dl; −7.8%) and blood glucose. Similarly, redox status was significantly improved only after the Kamut intervention phase, as measured by a reduction in both thiobarbituric acid reactive substances (−0.17 nmol/ml; −21.5%;) and carbonyl levels (−0.16 nmol/ml; −17.6%). The replacement diet with Kamut products also resulted in a significant increase of serum potassium and magnesium. Circulating levels of key pro-inflammatory cytokines (interleukin (IL)-6, IL-12, tumour necrosis factor-α and vascular endothelial growth factor) were significantly reduced after the consumption of Kamut products.Conclusions:The present results suggest that a replacement diet with Kamut products could be effective in reducing metabolic risk factors, markers of both oxidative stress and inflammatory status.

Self-organized crystallization patterns from evaporating droplets of common wheat grain leakages as a potential tool for quality analysis.

We studied the evaporation-induced pattern formation in droplets of common wheat kernel leakages prepared out of ancient and modern wheat cultivars as a possible tool for wheat quality analysis. The experiments showed that the substances which passed into the water during the soaking of the kernels created crystalline structures with different degrees of complexity while the droplets were evaporating. The forms ranged from spots and simple structures with single ramifications, through dendrites, up to highly organized hexagonal shapes and fractal-like structures. The patterns were observed and photographed using dark field microscopy in small magnifications. The evaluation of the patterns was performed both visually and by means of the fractal dimension analysis. From the results, it can be inferred that the wheat cultivars differed in their pattern-forming capacities. Two of the analyzed wheat cultivars showed poor pattern formation, whereas another two created well-formed and complex patterns. Additionally, the wheat cultivars were analyzed for their vigor by means of the germination test and measurement of the electrical conductivity of the grain leakages. The results showed that the more vigorous cultivars also created more complex patterns, whereas the weaker cultivars created predominantly poor forms. This observation suggests a correlation between the wheat seed quality and droplet evaporation patterns.

Genetic diversity assessment in Somali sorghum (Sorghum bicolor (L.) Moench) accessions using microsatellite markers

In the north-western region of Somalia, bordering Ethiopia, sorghum represents an important resources for human and animal nutrition. The critical situation of Somalia is threatening the preservation of this valuable resource and it becomes urgent to develop a strategy of correct evaluation of the sorghum germplasm in order to promote conservation and preservation programs. Microsatellites, also known as Simple Sequence Repeats (SSRs), are reproducible molecular markers useful in assessing the level of genetic diversity of plants. A total of 5 sorghum SSR-specific primer pairs were used to assess the genetic diversity of Somali sorghum landraces. Extensive variation was found at the microsatellite loci analysed, except for a locus that resulted in a monomorphic for some accessions. Considerable differences were found between total and effective number of alleles indicating non uniform allele frequency. Moreover allele frequency at a single locus significantly changed among accessions. Total gene diversity calculated for each locus ranged from 0.44 to 0.79. Most of the genetic diversity occurred within accessions demonstrating that accessions are not under selection processes and/or there is a continuous exchange of genes between sorghum populations. In any case, the patterns of clustering were significantly affected by the presence/absence of some alleles with high discriminant weight. Accessions Carabi, Abaadiro, Masego Cas and Masego Cad represent distinct genotypes confirming finding observed in previous phenotypic studies. The results highlight the central role of local farmers in maintaining and shaping local germplasm.

Storage-protein variation in wild emmer (Triticum turgidum ssp. dicoccoides) from Jordan and Turkey. II: Patterns of allele distribution

Genetic diversity in the seed storage-proteins encoded at theGlu-A1,Glu-B1 andGli-B1/Glu-B3 loci was studied electrophoretically in 315 individuals belonging to nine populations ofT. dicoccoides from Jordan and three from Turkey. The inter- and intra-population distribution of seed storage-protein alleles at the considered loci and its link with geographical factors were investigated. Population differentiation in seed storage-proteins was in some cases very high with very weak correlations with geographic distance. Greater gene differentiation was found within and between populations which were geographically very close in Jordan than between those from Jordan and Turkey. However the distribution of alleles appeared to be non random. Samples collected from populations at locations over 900 m above sea level were less polymorphic than those collected at lower altitudes (500–700 m), whereas the relative genetic differentiation between populations was greater between those collected at higher altitudes. Seed storage-protein differentiation was significantly correlated with the altitude of the collecting sites. Although it is difficult to point out the selective pressure of altitude per se, altitude can reflect an integration of several environmental parameters. The possible adaptive value of seed storage-proteins is discussed.

Asian chestnut gall wasp in Tuscany: gall characteristics, egg distribution and chestnut cultivar susceptibility

1 Preliminary investigations were carried out on Dryocosmus kuriphilus Yasumatsu on Castanea sativa Miller in Tuscany to assess variations in gall characteristics in coppice and high forest at two crown heights (height < 2 or 2–6 m), influence of bud size and bud position on oviposition rates and susceptibility of three cultivars. 2 Gall size may depend on various factors, including wasp population density. In the present study area, small galls (with one or two cells) were the most numerous in 2008, whereas larger galls (with more than three cells) prevailed in 2009. 3 Dryocosmus kuriphilus oviposition occurrence was influenced by both bud size and bud position. Buds with eggs tended to be larger in size compared with bud without eggs, suggesting that D. kuriphilus females prefer to lay eggs in larger buds (approximately 6 mm3) compared with smaller buds (approximately 3 mm3). The mean number of eggs per bud tended to decrease from the apical bud toward the basal bud. 4 Three C. sativa cultivars, Carpinese, Fusca and Cesurone, were examined. Fusca grafts had significantly more galls compared with Carpinese and Cesurone, whereas Cesurone grafts had more larvae per bud compared with Carpinese and Fusca. Overall, the Carpinese cultivar may be less susceptible to D. kuriphilus galling compared with the Fusca and Cesurone cultivars.

Effects of Short-Term Consumption of Bread Obtained by an Old Italian Grain Variety on Lipid, Inflammatory, and Hemorheological Variables: An Intervention Study

The aim of this study was to evaluate the influence of short-term dietary intake of bread obtained by a selected variety of old grain grown in Tuscany, Italy on some parameters related to the atherosclerotic process. Twenty healthy subjects (median age, 39.5 years) followed for 10 weeks a diet containing bread (150 g/day) made from the test grain (test period) and for the same period a diet containing commercially available bread of the same quantity (control period). Lipid, inflammatory, and hemorheological profiles before and after dietary intervention were evaluated. The test period showed a significant (P < .05) improvement of total cholesterol (pre-intervention, 211.2 +/- 10.8 mg/dL; post-intervention, 196.5 +/- 9.8 mg/dL) and low-density lipoprotein-cholesterol levels (pre-intervention, 137.5 +/- 8.1 mg/dL; post-intervention, 119.5 +/- 7.5 mg/dL), whereas no significant changes during the control period were observed. With regard to inflammatory and hemorheological parameters, the test period showed a significant decrease in some of the parameters investigated (interleukin-8 [pre-intervention vs. post-intervention, 67.4 +/- 10.7 vs. 43.9 +/- 4.1 pg/mL], whole blood viscosity at high [4.36 +/- 0.03 vs. 4.32 +/- 0.03 mPa x s, respectively] and low [26.1 +/- 0.4 vs. 24.8 +/- 0.5 mPa x s, respectively] shear rates, and erythrocyte filtration [8.4 +/- 0.7% vs. 9.1 +/- 0.6%, respectively]) relative to the control period, which showed no significant changes. Short-term dietary intake of whole grain bread obtained from an old grain variety seems to impose a favorable status with regard to lower circulating levels of markers of atherosclerosis.

The bean polygalacturonase-inhibiting protein 2 (PvPGIP2) is highly conserved in common bean (Phaseolus vulgaris L.) germplasm and related species.

Polygalacturonase-inhibiting proteins (PGIPs) are extracellular plant protein inhibitors of endo-polygalacturonases (PGs) that belong to the leucine-rich repeat (LRR) protein family. In bean, PGIP is encoded by a small gene family of four members among which Pvpgip2 encodes the most wide-spectrum and efficient inhibitor of fungal PGs. In order to evaluate the sequence polymorphism of Pvpgip2 and its functional significance, we have analyzed a number of wild and cultivated bean (P. vulgaris) accessions of Andean and Mesoamerican origin, and some genotypes from the related species P. coccineus, P. acutifolius, and P. lunatus. Our analyses indicate that the protein encoded by Pvpgip2 is highly conserved in the bean germplasm. The few detected polymorphic sites correspond to synonymous substitutions and only two wild genotypes contain a Pvpgip2 with a single non-synonymous replacement. Sequence comparison showed a slightly larger variation in the related bean species P. coccineus, P. acutifolius, and P. lunatus and confirmed the known phylogenetic relationships with P. vulgaris. The majority of the replacements were within the xxLxLxx region of the leucine rich repeat (LRR) domain and none of them affected residues contributing to structural features. The variant PGIPs were expressed in Nicotiana benthamiana using PVX as vector and their inhibitory activity compared to that of PvPPGIP2. All the variants were able to fully inhibit the four fungal PGs tested with minor differences. Taken together these results support the hypothesis that the overall sequence conservation of PGIP2 and minor variation at specific sites is necessary for high-affinity recognition of different fungal PGs.

Effects of the lack of proteins controlled by genes at the Gli-D1/Glu-D3 loci on the breadmaking quality of wheat

Flours from the F4 progeny of a cross between the bread wheat cultivar Cheyenne and a line lacking gliadin components and low molecular weight subunits of glutenin controlled by the tightly linked genes at the Gli-DI and Glu-D3 loci were examined electrophoretically. Quality relationships were established using the SDS-sedimentation test. The results showed a large detrimental effect due to the lack of the above protein components, which was even larger than the negative effect observed when the null allele was compared with the 2* allele at the Glu-AI locus. The present results also indicated that the alleles of Cheyenne at the Gli-B1 locus were superior to those contributed by MG 27116. They also indicated the possible presence of effects due to gene interactions, which should be considered carefully in breeding programmes aimed at improving wheat technological properties.