Roberto Lo Scalzo

Partial removal of water before freezing: cultivar and pre-treatments as quality factors of frozen muskmelon (Cucumis melo, cv reticulatus Naud.)

Abstract The influence of both the cultivar and the dehydration method, applied before freezing, on quality characteristics of dehydrofrozen muskmelon spheres has been studied. Water was removed from muskmelon cultivar Mirado and Rony, prior to freezing, by Dewatering–Impregnation–Soaking in concentrated solution (DIS) for 1 h, air dehydration and combined DIS-air dehydration to a final 50% weight reduction. The results of the analysis of exudate loss, texture, colour, aroma composition and sensory characteristics ascertained the crucial importance of the cultivar which had a great influence on the quality of the end products. Moisture reduction prior to freezing reduced exudate loss and improved texture at thawing. All the pre-treatments caused the loss of ethyl esters, namely “positive” aroma compounds, while the alcohols, “negative” aroma compounds, increased in air dehydrated fruits and remained stable in the DIS-treated ones. This finding could explain the higher sensory acceptability of the DIS-treated fruit when compared with those pre-air dehydrated.

Open field trial of genetically modified parthenocarpic tomato: seedlessness and fruit quality

BackgroundParthenocarpic tomato lines transgenic for the DefH9-RI-iaaM gene have been cultivated under open field conditions to address some aspects of the equivalence of genetically modified (GM) fruit in comparison to controls (non-GM).ResultsUnder open field cultivation conditions, two tomato lines (UC 82) transgenic for the DefH9-RI-iaaM gene produced parthenocarpic fruits. DefH9-RI-iaaM fruits were either seedless or contained very few seeds. GM fruit quality, with the exception of a higher β-carotene level, did not show any difference, neither technological (colour, firmness, dry matter, °Brix, pH) nor chemical (titratable acidity, organic acids, lycopene, tomatine, total polyphenols and antioxidant capacity – TEAC), when compared to that of fruits from control line. Highly significant differences in quality traits exist between the tomato F1 commercial hybrid Allflesh and the three UC 82 genotypes tested, regardless of whether or not they are GM. Total yield per plant did not differ between GM and parental line UC 82. Fruit number was increased in GM lines, and GM fruit weight was decreased.ConclusionThe use in the diet of fruits from a new line or variety introduces much greater changes than the consumption of GM fruits in comparison to its genetic background. Parthenocarpic fruits, produced under open field conditions, contained 10-fold less seeds than control fruits. Thus parthenocarpy caused by DefH9-RI-iaaM gene represents also a tool for mitigating GM seeds dispersal in the environment.

Steam-Blanched Highbush Blueberry (Vaccinium corymbosum L.) Juice : Phenolic Profile and Antioxidant Capacity in Relation to Cultivar Selection

High-quality standards in blueberry juice can be obtained only taking into account fruit compositional variability and its preservation along the processing chain. In this work, five highbush blueberry cultivars from the same environmental growing conditions were individually processed into juice after an initial blanching step and the influence was studied of the cultivar on juice phenolic content, distribution and relative antioxidant activity, measured as scavenging capacity on the artificial free-radical 2,2-diphenyl-1-picrylhydrazyl (DPPH*). A chromatographic protocol was developed to separate all main phenolic compounds in berries. A total of 15 glycosylated anthocyanins, catechin, galactoside, glucoside, and rhamnoside quercetin 3-derivatives, and main benzoic and cinnamic acids were identified. The total content and relative distribution in anthocyanins, chlorogenic acid, and quercetin of each juice were dependent upon cultivar, and the total content was highly correlated (rxy=0.97) to the antioxidant capacity. A selective protective effect of berry blanching in juice processing can be observed on more labile anthocyanin compounds.

Thermal Treatment of Eggplant (Solanum melongena L.) Increases the Antioxidant Content and the Inhibitory Effect on Human Neutrophil Burst

The aim of this study was to compare the amount and activity of phytonutrients in raw, grilled, and boiled eggplant fruit using chemical measures and a biological assay of oxidative bursts in human neutrophils. The thermally treated samples showed various changes in their chemical composition (dry matter, soluble solids, acidity, and the amount of alcohol insoluble substances) due to the cooking processes and were much richer in the main phenolic compounds such as chlorogenic and caffeic acids, which are known to be antioxidants. Consequently, their free radical scavenging activity was significantly higher, especially that of superoxide anion. The biological assay of oxidative bursts from human neutrophils in the presence of N-formyl-methionyl-leucyl-phenylalanine confirmed the greater activity of extracts of the cooked eggplants with respect to raw eggplants. Successive extract dilutions showed a significant activity up to 1.25 microg/mL after cooking, while raw fruits resulted in an activity up to 10.00 microg/mL. These results showed that the thermal treatment commonly used before consumption can increase the content and biological activity of antioxidant compounds of eggplants.

Characterization of Health-Related Compounds in Eggplant (Solanum melongena L.) Lines Derived from Introgression of Allied Species

The purpose of the present study was to investigate the levels of either the nutraceutical and health-promoting compounds or the antioxidant properties of innovative eggplant (Solanum melongena L.) genotypes tolerant and/or resistant to fungi, derived from conventional and non-conventional breeding methodologies (i.e., sexual interspecific hybridization, interspecific protoplast electrofusion, androgenesis, and backcross cycles) in comparison with their allied and cultivated parents. Chemical measures of soluble refractometric residue (SRR), glycoalkaloids (solamargine and solasonine), chlorogenic acid (CA), delphinidin 3-rutinoside (D3R), total phenols (TP), polyphenoloxidase (PPO) activity, antiradical activity on superoxide anion and hydroxyl radical were carried out in raw fruit and peel of 57 eggplant advanced introgression lines (ILs), of three eggplant recurrent genotypes and of three allied species during 2005 and 2006. The majority of the ILs, obtained after several backcross cycles, showed positive characteristics with respect to the allied parents such as good levels of SRR, CA, D3R, TP, PPO activity, the scavenging activity against superoxide anion and hydroxyl radical and, in particular, significantly (p <or= 0.05) reduced concentrations of the toxic steroidal glycoalkaloids, solasonine and solamargine. These results showed the possibility to obtain new eggplant genotypes bearing useful traits derived from the allied parents (i.e., resistance/tolerance to plant pathogen fungi) together with nutraceutical and antioxidant properties typical of the cultivated species.

'Annurca' apple fruit, a southern Italy apple cultivar : textural properties and aroma composition

‘Annurca’ apple fruit, which is commonly cultivated in southern Italy and undergoes a typical reddening treatment and, is notable for its high firmness and its characteristic flavour, was examined for its pectic and aroma composition. Pectin, extracted with a water solution of potassium oxalate and dimethylsulphoxide, was found to be quantitavely and qualitatively important for its contribution to the high tissue firmness. Pectin changes its composition during the reddening process and there is even a difference in the pectic composition of the two ‘Annurca’ clones examined in this paper, ‘Standard’ and ‘Rossa del Sud’. Volatile compounds were collected by headspace sampling of intact unreddened and reddened fruits. Thirty-one compounds of several chemical classes were identified, to establish their role in the characteristic flavor of this apple cv. Among these compounds, n-pentanol was unusually present in large amounts; also δ-octalactone, never found in apples, was present.

Variations in the phytochemical contents and antioxidant capacity of organically and conventionally grown Italian cauliflower (Brassica oleracea L. subsp. botrytis): results from a three-year field study.

A three-year field study (2009-2011) was performed to evaluate phytochemicals and antioxidant capacities of two genotypes (HF1 Emeraude and the local variety, Velox) of green cauliflower grown under organic and conventional management. The conventional system increased yield, but had little effect on the dry matter, whereas the organic system increased the soluble solids. Phytochemicals and antioxidant capacity showed significant year-to-year variability. During the third year, the scarce rainfall determined a significant increase of total glucosinolates and a general decrease of antioxidants in all samples. Interestingly, in the same year organic plants were less affected by the unfavorable climatic conditions, as they increased ascorbic acid, polyphenols, and carotenoids with respect to conventional ones. The overall results for the three years showed that the two genotypes responded differently. Compared to the conventional system, Velox showed 24, 21, 13, 48, and 44% higher content of ascorbic acid, polyphenols, carotenoids, volatiles, and antioxidant capacity, respectively. In contrast, no significant increase in the phytochemicals or the antioxidant potential was found in organic Emeraude, with the exception of total volatiles (+41%). These findings suggest that organic cultivation may be highly effective for particular cauliflower genotypes.

Mapping Quantitative Trait Loci Affecting Biochemical and Morphological Fruit Properties in Eggplant (Solanum melongena L.)

Eggplant berries are a source of health-promoting metabolites including antioxidant and nutraceutical compounds, mainly anthocyanins and chlorogenic acid; however, they also contain some anti-nutritional compounds such as steroidal glycoalkaloids (SGA) and saponins, which are responsible for the bitter taste of the flesh and with potential toxic effects on humans. Up to now, Quantitative Trait Loci (QTL) for the metabolic content are far from being characterized in eggplant, thus hampering the application of breeding programs aimed at improving its fruit quality. Here we report on the identification of some QTL for the fruit metabolic content in an F2 intraspecific mapping population of 156 individuals, obtained by crossing the eggplant breeding lines “305E40” × “67/3.” The same population was previously employed for the development of a RAD-tag based linkage map and the identification of QTL associated to morphological and physiological traits. The mapping population was biochemically characterized for both fruit basic qualitative data, like dry matter, °Brix, sugars, and organic acids, as well as for health-related compounds such chlorogenic acid, (the main flesh monomeric phenol), the two peel anthocyanins [i.e., delphinidin-3-rutinoside (D3R) and delphinidin-3-(p- coumaroylrutinoside)-5-glucoside (nasunin)] and the two main steroidal glycoalkaloids, solasonine, and solamargine. For most of the traits, one major QTL (PVE ≥10%) was spotted and putative orthologies with other Solanaceae crops are discussed. The present results supply valuable information to eggplant breeders on the inheritance of key fruit quality traits, thus providing potential tools to assist future breeding programs.

A Polyphenol Rich Extract from Solanum melongena L. DR2 Peel Exhibits Antioxidant Properties and Anti-Herpes Simplex Virus Type 1 Activity In Vitro

DR2B and DR2C extracts, obtained by ethanolic maceration of peel from commercially and physiologically ripe aubergine berries, were studied for the antioxidative cytoprotective properties and anti-HSV-1 activity, in line with the evidence that several antioxidants can impair viral replication by maintaining reducing conditions in host cells. The antioxidative cytoprotective effects against tBOOH-induced damage were assessed in Caco2 cells, while antiviral activity was studied in Vero cells; polyphenolic fingerprints were characterized by integrated phytochemical methods. Results highlighted different compositions of the extracts, with chlorogenic acid and delphinidin-3-rutinoside as the major constituents; other peculiar phytochemicals were also identified. Both samples reduced reactive oxygen species (ROS) production and exhibited scavenging and chelating properties. DR2C partly counteracted the tBOOH-induced cytotoxicity, with a remarkable lowering of lactate metabolism under both normoxia and hypoxia; interestingly, it increased intracellular GSH levels. Furthermore, DR2C inhibited the HSV-1 replication when added for 24 h after viral adsorption, as also confirmed by the reduction of many viral proteins’ expression. Since DR2C was able to reduce NOX4 expression during HSV-1 infection, its antiviral activity may be correlated to its antioxidant properties. Although further studies are needed to better characterize DR2C activity, the results suggest this extract as a promising new anti-HSV-1 agent.

Phytochemical Concentrations and Antioxidant Capacity of Grapes Treated with Low Copper Formulations against Downy Mildew

A two-year study was conducted in an organic vineyard to evaluate the phytochemical concentrations and antioxidant capacity of grapes treated with low copper for downy mildew control compared to grapes that were untreated or treated with a standard fungicide. The metabolic profile, antioxidant capacity, and downy mildew incidence and severity were assessed. The maturity of grapes was an important factor in determining the potential risk for the spread of fungal disease, as suggested by principle components analysis (PCA), which showed a positive relationship between tartaric acid concentration and both incidence and severity of downy mildew disease. Polyphenols and thiols were more abundant in berries with less disease. The thiols were highly correlated with the antioxidant capacity, indicating an important role of these metabolites in determining the antioxidant potential of grape berries. Moreover, both the antioxidant indexes and thiols in the PCA were plotted opposite the disease severity and incidence, suggesting that higher antioxidant potential may be responsible for an increased capacity of grapes to counteract the disease. Results showed that low-copper formulations could control grape downy mildew in the field with a similar efficacy to the standard reference fungicide, without affecting the phytochemical profile and the antioxidant potential of grapes. Low-copper formulations may be thus considered alternatives for organic agriculture that minimize costs and copper accumulation in the soil, thus ensuring grape quality in a sustainable crop management system.