Antioxidant Activity of Free and Bound Compounds in Quinoa (Chenopodium quinoa Willd.) Seeds in Comparison with Durum Wheat and Emmer

Antioxidant activity (AA) of quinoa (Chenopodium quinoa Willd.) seeds, as well as of durum wheat (Triticum turgidum L. ssp. durum Desf.) and of emmer (T. turgidum L. ssp. dicoccum Sch¨ubler) grains, was evaluated by studying hydrophilic (H), lipophilic (L), free-soluble (FSP) and insoluble-bound (IBP) phenolic extracts using the new lipoxygenase/4-nitroso-N,N-dimethylaniline (LOX/RNO) method, able to simultaneously detect different antioxidant mechanisms, as well as using the Oxygen Radical Absorbance Capacity (ORAC) and the Trolox Equivalent Antioxidant Capacity (TEAC) assays, which measure the scavenging activity against peroxyl and ABTS [2,2-azino-bis-(3- ethylbenzothiazoline-6-sulfonate)] radicals, respectively. The species under study were compared with respect to the sum of AA values of H, L and FSP extracts (AAH+L+FSP), containing freely solvent-soluble antioxidants, and AA values of IBP extracts (AAIBP), representing the phenolic fraction ester-linked to insoluble cell wall polymers. The LOX/RNO and ORAC methods measured in quinoa flour a remarkable AAH+L+FSP higher than durum wheat, although lower than emmer; according to the same assays, the IBP component of quinoa resulted less active than the durum wheat and emmer ones. The TEAC protocol also revealed a high AAH+L+FSP for quinoa. Interestingly, the ratio AAH+L+FSP/AAH+L+FSP+IBP, as evaluated by the LOX/RNO and ORAC assays, resulted in quinoa higher than that of both durum wheat and emmer, and much higher than durum wheat, according to the TEAC protocol. This may suggest that antioxidants from quinoa seeds may be more readily accessible with respect to that of both the examined wheat species

Effect of Arbuscular Mycorrhizal Fungal Seed Coating on Grain Protein and Mineral Composition of Old and Modern Bread Wheat Genotypes

The effect of arbuscular mycorrhizal fungi (AMF) on yield and quality was investigated on a set of seven bread wheat genotypes with varying years of release, including five old genotypes and two modern varieties. A two-year field trial was conducted in central Italy under rainfed con- ditions. The effect of AM fungal seed coating was proved by assessing the AM fungal root colonization and studied on agronomic and quality traits, and in particular on gluten-forming proteins and grain mineral composition. AMF seed coating led to a general yield improvement in old geno- types (+24%). Concerning the effects on grain quality, while modern genotypes showed an increase in protein content (+16%), in the old ones an improvement of gluten quality was observed, with an increased proportion of HMW-GS from +17% to +92%. The gluten index results were mostly influenced by HMW-GS allelic configuration and amount, showing a significant correlation with gliadin- to-glutenin ratio and HMW-GS to LMW-GS. Concerning mineral uptake, AM fungal treatment de- termined a general increase in P content, which was more marked in the modern group (+44%). Furthermore, AMF significantly increased mean Fe concentration in Verna (+53%) and Bologna (+45%). Finally, phytate content did not increase with AMF, without affecting mineral bioavailability

Analysis of gluten proteins composition during grain filling in two durum wheat cultivars submitted to two water regimes

Durum wheat ( Triticum turgidum L. subsp . durum) is one of the major crops in the Mediterranean basin, where water stress often occurs during grain filling which represents a critical stage for the synthesis and accumulation of storage proteins (gliadins and glutenins). The aim of the study is to evaluate, by two-dimensional gel electrophoresis (2DE SDS-PAGE), the storage proteins composition of two durum wheat cultivars (Ciccio and Svevo) cultivated in a growth chamber under two different water regimes (control and water deficit). At milk stage and physiological maturity, gluten proteins have been extracted and separated by 2DE SDS-PAGE. The analysis of the gels was performed by the software ImageMaster 2D Platinum (Amersham). The results showed differences in protein expression within the different gel regions between water regimes and cultivars; under water deficit the rate of protein accumulation was faster for all the protein regions, either at milk and physiological stage. Protein accumulation within high molecular weight (H) region resulted faster in Ciccio than in Svevo mainly in the control treatment. In the low molecular weight region between 48 and 35 kDa (L 48-35), the cultivar Ciccio showed a higher protein expression than Svevo. Furthermore under water deficit a marked increase in H region volume and a decrease in the L 48-35 region was observed only for Svevo; instead in Ciccio no change was observed showing this cultivar a greater stability on changing water regime. Further studies by the use of mass spectrometry are necessary to identify specific peptides relative to drought stress during grain filling as well as to investigate the relationships with technological quality

Influence of Organic and Conventional Farming on Grain Yield and Protein Composition of Chickpea Genotypes

Chickpea is a key crop in sustainable cropping systems and for its nutritional value. Studies on agronomic and genetic influences on chickpea protein composition are missing. In order to obtain a deep insight into the genetic response of chickpeas to management in relation to agronomic and quality traits, a two-year field trial was carried out with eight chickpea genotypes under an organic and conventional cropping system. Protein composition was assessed by SDS-PAGE in relation to the main fractions (vicilin, convicilin, legumin, lectin, 2s-albumin). Crop response was highly influenced by year and presumably also by management, with a −50% decrease in grain yield under organic farming, mainly due to a reduction in seed number per m2. No effect of crop management was observed on protein content, despite significant differences in terms of protein composition. The ratio between the major globulins, 7s vicilin and 11s legumin, showed a negative relationship with grain yield and was found to be higher under organic farming. Among genotypes, black-seed Nero Senise was characterized by the highest productivity and water-holding capacity, associated with low lectin content. These findings highlight the importance of the choice of chickpea genotypes for cultivation under organic farming in relation to both agronomic performance and technological and health quality

Functional, textural and sensory properties of dry pasta supplemented with lyophilized tomato matrix or with durum wheat bran extracts produced by supercritical carbon dioxide or ultrasound

A study was carried out to produce functional pasta by adding bran aqueous extract (BW) and bran oleoresin (BO) obtained using ultrasound and supercritical CO2, respectively, or a powdery lyophilized tomato matrix (LT). The bioactive compounds, hydrophilic and lipophilic antioxidant activity (HAA and LAA) in vitro, were evaluated. BW supplementation did not improve antioxidant activity, whilst LT pasta showed unconventional taste and odor. BO pasta had good levels of tocochromanols (2551μg/100g pasta f.w.) and carotenoids (40.2μg/100g pasta f.w.), and the highest HAA and LAA. The oleoresin altered starch swelling and gluten network, as evidenced by scanning electron microscopy, therefore BO pasta had structural characteristics poor compared with the control (4.8% vs. 3.2% cooking loss), although this difference did not affect significantly overall sensory judgment (74 vs. 79 for BO and control, respectively). BO supplementation was most effective for increasing antioxidant activity without jeopardizing pasta quality

Antioxidant capacity, phenolic and vitamin C contents of quinoa (Chenopodium quinoa Willd.) as affected by sprouting and storage conditions

Antioxidant capacity (AC) of quinoa (Chenopodium quinoa Willd. cv. Real) seeds and sprouts obtained after 4 days of seed germination at 20°C and 70% humidity was evaluated using trolox equivalent antioxidant capacity (TEAC) and oxygen radical absorbance capacity (ORAC) assays, able to highlight reducing activity and peroxyl radical scavenging capacity, respectively; phenolic content (PC) was also measured. Both TEAC and ORAC assays revealed a significantly higher (about 2- and 2.8-fold, respectively) AC of 4-day-old sprouts compared to seeds; consistently, also PC values of sprouts resulted about 2.6 times higher than seeds. In order to investigate the influence of storage on AC and PC, as well as on vitamin C content (VCC), 4-day-old sprouts were subjected for 7 days at 5°C to three different conditions of controlled atmosphere storage (CAS) compared with air. Interestingly, whatever the CAS conditions, storage of quinoa sprouts up to 7 days induced an increase of AC evaluated in terms of reducing activity by TEAC assay. Consistently, an increase of PC and VCC was measured during storage, positively correlated to TEAC values. Moreover, a decrease of peroxyl radical scavenging activity, measured by ORAC, was observed after 7 days of storage, in accordance with a shift of AC towards the reducing activity component. Overall, these findings indicate that sprouting approach using quinoa may provide highly antioxidant-enriched seedlings that may improve nutritional quality of diet or of functional foods. Interestingly, antioxidant properties of quinoa sprouts may be deeply influenced by storage, able to increase reducing activity by increasing phenols and vitamin C

Nutritional and technological quality of the durum wheat

Durum wheat quality is a complex system that combines yield characteristics, cultivation conditions and certification requirements. In this review, the technological and nutritional aspects of grain quality were evaluated in relation to the influence of climate and agronomic practices. In particular, the technological quality was investigated with regard to the kind of processed product (pasta, bread, couscous, burghul). The influence of nitrogen and sulphur nutrition, temperature, water regime and organic farming on grain quality was evaluated. Furthermore, the nutritional characteristics of durum wheat related to starch, proteins, lipids, vitamins, fibres and mineral ions content were examined. Special focus was on the antioxidant activity capable of preventing chronic and degenerative diseases thanks to the high content in bioactive compounds, as phenols, tocols, carotenoids and fibres in whole grain. In the light of the new direction of the Community agricultural policy and of the growing interest in human nutrition, two prospects for development of the durum wheat sector were delineated: i) developing certified products (PGI, PDO and organic); ii) promoting production and processing technologies aimed at increasing the level of bioactive compounds in durum wheat grain and its by-products

Qualità nutrizionale e tecnologica del frumento duro.

Durum wheat quality is a complex system that combines yield characteristics, cultivation conditions and certification requirements. In this review, the technological and nutritional aspects of grain quality were evaluated in relation to the influence of climate and agronomic practices. In particular, the technological quality was investigated with regard to the kind of processed product (pasta, bread, couscous, burghul). The influence of nitrogen and sulphur nutrition, temperature, water regime and organic farming on grain quality was evaluated. Furthermore, the nutritional characteristics of durum wheat related to starch, proteins, lipids, vitamins, fibres and mineral ions content were examined. Special focus was on the antioxidant activity capable of preventing chronic and degenerative diseases thanks to the high content in bioactive compounds, as phenols, tocols, carotenoids and fibres in whole grain. In the light of the new direction of the Community agricultural policy and of the growing interest in human nutrition, two prospects for development of the durum wheat sector were delineated: i) developing certified products (PGI, PDO and organic); ii) promoting production and processing technologies aimed at increasing the level of bioactive compounds in durum wheat grain and its by-products