Antioxidant nutritional quality of tomato

Application of Trichoderma harzianum, 6-pentyl-α-pyrone and Plant Biopolymer Formulations Modulate Plant Metabolism and Fruit Quality of Plum Tomatoes

Many Trichoderma are successfully used to improve agriculture productivity due to their capacity for biocontrol and to stimulate plant growth and tolerance to abiotic stress. This research elucidates the effect of applications with Trichoderma harzianum strain T22 (T22), or biopolymer (BP) alone or in combination (BP + T22 or BP + 6-pentyl-α-pyrone (6PP); a Trichoderma secondary metabolite) on the crop performance, nutritional and functional quality of greenhouse tomato (Solanum lycopersicum L. cultivar Pixel). T22 elicited significant increases in total yield (+40.1%) compared to untreated tomato. The content of lycopene, an important antioxidant compound in tomatoes, significantly increased upon treatment with T22 (+ 49%), BP + T22 (+ 40%) and BP + 6PP (+ 52%) compared to the control. T22 treatments significantly increased the content of asparagine (+37%), GABA (+87%) and MEA (+102%) over the control; whereas BP alone strongly increased GABA (+105%) and MEA (+85%). The synthesis of these compounds implies that tomato plants are able to reuse the photorespiratory amino acids and ammonium for producing useful metabolites and reduce the pressure of photorespiration on plant metabolism, thus optimizing photosynthesis and growth. Finally, these metabolites exert many beneficial effects for human health, thus enhancing the premium quality of plum tomatoes.

Tangerine tomatoes: origin, biochemistry, potential health benefits and future prospects

BACKGROUND

Tomatoes and lycopene have been associated with the prevention of chronic diseases. Tetra-cis lycopene from tangerine tomatoes has been reported to be more bioavailable than the all-trans isomer found in red tomatoes. Therefore, tangerine tomatoes might contain superior health benefits compared to those of red tomatoes.

SCOPE AND APPROACH

This review focuses on the origin, biochemistry, nutritional composition, and potential health benefits of tangerine tomatoes, as well as their comparison with those of the red and high-β-carotene varieties. Information gathered from numerous studies on tomatoes, as well as conflicting perspectives, have been summarized to provide an unbiased review.

KEY FINDINGS AND CONCLUSION

The origin of tangerine tomatoes is disputable, but they were reportedly present from as early as 1934. The carotenoid biosynthesis pathway underlying the accumulation of tetra-cis lycopene in tangerine tomatoes has been well defined. However, the nutritional composition of tangerine tomatoes is not currently publicly available. The carotenoid composition of tangerine tomatoes is unique not only because of the presence of tetra-cis lycopene, but also due to the relatively high content of phytoene, phytofluene, ζ-carotene, and neurosporene relative to other tomato varieties. Although a few in vitro and in vivo studies have shown promising results, further studies are required to validate the health benefits of tangerine tomatoes. Furthermore, published data regarding the potential health benefits of tangerine tomatoes on cardiovascular and bone health is currently lacking even though red tomatoes have shown promise in these areas.

Optimizing N Fertilization to Improve Yield, Technological and Nutritional Quality of Tomato Grown in High Fertility Soil Conditions

Processing tomato is the second most important worldwide cash crop, generally produced in high-input systems. However, fruit yield and quality are affected by agronomic management, particularly nitrogen (N) fertilization, whose application to indeterminate growth genotypes for canning has yet to be investigated in depth. Hence, the objective of this work was to assess the effects of different N rates (0, 50, 125, 200, 275, and 350 kg ha-1) on fruit yield and quality characteristics of processing tomato 'San Marzano' landrace. The results of our study showed that 125 and 200 kg of N ha-1 are the most appropriate rates in soil with high fertility, ensuring the highest values of marketable yield and brix yield. However, plants fertilized with 125 kg of N ha-1 attained higher values of N efficiency and fruit K and P concentrations than plants fertilized with 200 kg of N ha-1. Our results suggest that overdoses of N supplies negatively affected fruit yield and quality of San Marzano landrace grown in high soil fertility conditions, also reducing the agricultural sustainability. Hence, specific agronomic protocol and extension services are required to optimally manage tomato crop systems.

Parameters of antioxidant activity of Galega officinalis L. and Galega orientalis Lam. (Fabaceae Lindl.) plant raw material

The plant raw material of Galega officinalis L. (goat’s rue) and Galega orientalis Lam. (fodder galega) investigated in this study. These species are known as fodder crops with high productivity of green mass and as medicine plants. The current study was aimed to evaluate an accumulation in dry raw of selected plants the total content of phenolic acids (TPA) and flavonoids (TFC) as compounds with antioxidant activity (AA) by spectrophotometric method. AA by DPPH-method and phosphomolybdenum method (reducing power (RP)) was measured. Study of ethanolic extracts of G. officinalis showed accumulation of TPA in different organs in range from 3.65 to 15.17 mg.g-1 caffeic acid equivalent (CAE) and TFC from 10.08 to 65.75 mg.g-1 quercetin equivalent (QE), AA by DPPH-method from 6.02 to 8.45 mg.g-1 Trolox equivalent (TE) and RP of extracts by phosphomolybdenum method from 86.56 to 288.15 mg TE.g-1. In extracts of G. orientalis was identified TPA from 3.52 to 18.52 mg CAE.g-1 and TFC from 6.09 to 46.72 mg QE.g-1, antioxidant activity by DPPH-method from 6.80 to 8.48 mg TE.g-1 and antioxidant capacity by phosphomolybdenum method from 52.52 to 188.51 mg TE.g-1. It was established that less concentration of studied compounds found in the stems for both species. It should be noted that the content of phenolic acids in the leaves was decreased and flavonoids in stems increased during vegetation for both species. Content of phenolic acids in the generative organs and flavonoids in the leaves decreased in raw of G. orientalis during vegetation. Pearson’s correlation analysis demonstrated very strong relations between TFC and AA by DPPH, TPA and RP, TFC and RP for G. officinalis extracts. Very strong correlation in the extracts of G. orientalis found between TFC and RP, TPA and RP. Obtained results can be used in the further biochemical and pharmacological study.

Mapping of quantitative trait loci for antioxidant molecules in tomato fruit: Carotenoids, vitamins C and E, glutathione and phenolic acids

The nutritional value of a crop lies not only in its protein, lipid, and sugar content but also involves compounds such as the antioxidants lycopene, β-carotene and vitamin C. In the present study, wild tomato Solanum pimpinellifolium LA 1589 was assessed for its potential to improve antioxidant content. This wild species was found to be a good source of alleles for increasing β-carotene, lycopene, vitamin C and vitamin E contents in cultivated tomato. Characterization of an LA 1589 interspecific inbred backcross line (IBL) mapping population revealed many individuals with transgressive segregation for the antioxidants confirming the usefulness of this wild species for breeding of these traits. Molecular markers were used to identify QTLs for the metabolites in the IBL population. In total, 64 QTLs were identified for the antioxidants and their locations were compared to the map positions of previously identified QTLs for confirmation. Four (57 %) of the carotenoid QTLs, four (36 %) of the vitamin QTLs, and 11 (25 %) of the phenolic acid QTLs were supported by previous studies. Furthermore, several potential candidate genes were identified for vitamins C and E and phenolic acids loci. These candidate genes might be used as markers in breeding programs to increase tomato's antioxidant content.

Fruits

Fruits come in a wide variety of colors, shapes, and flavors. This chapter will cover selected fruits that are known to be healthy and highly nutritious. These fruits were chosen due to their common usage and availability. Since it is not possible to cover all health benefits or essential nutrients and important phytochemicals of the fruit composition, this chapter will focus on the key valuable constituents and their potential health effects.

Multifaceted regulatory function of tomato SlTAF1 in the response to salinity stress

Salinity stress limits plant growth and has a major impact on agricultural productivity. Here, we identify NAC transcription factor SlTAF1 as a regulator of salt tolerance in cultivated tomato (Solanum lycopersicum). While overexpression of SlTAF1 improves salinity tolerance compared with wild-type, lowering SlTAF1 expression causes stronger salinity-induced damage. Under salt stress, shoots of SlTAF1 knockdown plants accumulate more toxic Na⁺ ions, while SlTAF1 overexpressors accumulate less ions, in accordance with an altered expression of the Na⁺ transporter genes SlHKT1;1 and SlHKT1;2. Furthermore, stomatal conductance and pore area are increased in SlTAF1 knockdown plants during salinity stress, but decreased in SlTAF1 overexpressors. We identified stress-related transcription factor, abscisic acid metabolism and defence-related genes as potential direct targets of SlTAF1, correlating it with reactive oxygen species scavenging capacity and changes in hormonal response. Salinity-induced changes in tricarboxylic acid cycle intermediates and amino acids are more pronounced in SlTAF1 knockdown than wild-type plants, but less so in SlTAF1 overexpressors. The osmoprotectant proline accumulates more in SlTAF1 overexpressors than knockdown plants. In summary, SlTAF1 controls the tomato's response to salinity stress by combating both osmotic stress and ion toxicity, highlighting this gene as a promising candidate for the future breeding of stress-tolerant crops.

Tomato as Potential Source of Natural Additives for Meat Industry. A Review

Tomato industry produces huge amounts of by-products that represent an environmental and economic problem. However, these by-products contain multiple bioactive compounds, which would make them a renewable source for obtaining natural antioxidants and colourants (carotenoids). This is in line with the preferences of the current consumer who demands more natural and healthy products. However, the lipophilic character of carotenoids means that their extraction must be carried out using toxic organic solvents. To overcome environmental and health problems of organic solvents, the application of supercritical fluid extraction (SFE) for the extraction of lipophilic compounds such as lycopene was used successfully, achieving yields similar to those obtained with conventional techniques. Nonetheless, the extraction conditions must be carefully selected, to obtain high yields and at the same time maintain a high antioxidant capacity. On the other hand, the use of tomato and tomato extracts as natural additives in meat products are reduced in comparison with other natural antioxidant/colourant extracts. However, different researches conclude that the use of tomato improved nutritional quality, reduced lipid oxidation and increased stability during the shelf-life period of meat products, while retaining or increasing sensory properties and overall acceptability, which converts tomato by-products into a promising source of natural additives.

The Influence of Lycopene, [6]-Gingerol, and Silymarin on the Apoptosis on U-118MG Glioblastoma Cells In Vitro Model

BACKGROUND

Lycopene, gingerol, and silymarin have a potential anticancer activity in many types of neoplasms. Healthy lifestyle and proper diet are associated with a reduced risk of cancer and other diseases. Increasingly, clinical research focuses on the mechanisms of action of natural compounds and their impact on the development of cancer. The aim of the present study was to determine the effect of lycopene, gingerol, and silymarin on apoptosis, mitochondrial potential and caspase-3/7 activity in the U118-MG cell line.

METHODS

Human glioblastoma cells were incubated with lycopene, [6]-gingerol, and silymarin for 24 and 48 h. Apoptosis was monitored using the Annexin V labelling, caspase-3/7 activity, and early hallmark of apoptosis were determined with mitochondrial membrane potential changes.

RESULTS

Our data showed a significant decrease in the viability glioblastoma cells U118-MG after 48 h treatment with lycopene, [6]-gingerol, and silymarin.

CONCLUSIONS

Our data could confirm the stimulative effects of used compounds on apoptosis and changes in mitochondrial potential in a dose-dependent manner.

Untargeted screening of the bound / free phenolic composition in tomato cultivars for industrial transformation

BACKGROUND

Tomato is one of the most important agricultural crops and it is characterized by a wide bioactive compound profile. However, little information is reported on its comprehensive polyphenol profile. In this work, 13 commercial tomato cultivars for industrial transformation were screened by ultra-high-pressure liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (UHPLC-QTOF-MS) for both free and bound phenolic profiles. Thereafter, the in vitro antioxidant activity of each cultivar was assessed by ferric reducing antioxidant power (FRAP) and oxygen radical absorbance activity (ORAC) assays. Multivariate statistics, i.e. orthogonal projection to latent structures discriminant analysis (OPLS-DA), were then used to model samples according to their distinct phenolic signatures, thus providing compounds that better discriminated between the distributions of the cultivars that were considered.

RESULTS

More than 350 phenolic compounds could be identified across the samples that were considered: flavonoids (such as flavones and flavanols), hydroxycinnamic acids, lignans, and lower-molecular-weight phenolics were the most frequently observed classes of phenolics in tomato berries. Anthocyanins were the most abundant class among bound phenolics (being highest in the Leader F1 and Defender F1 cultivars), followed by tyrosols (mainly in Heinz cultivars). However, flavones and hydroxybenzoic acids were the most represented discriminant phenolics in the bound fraction.

CONCLUSIONS

Untargeted metabolomics allowed significant differences in phenolic composition to be outlined across the tomato cultivars that were analyzed. Such differences were particularly evident regarding the free-to-bound phenolic ratio, hence allowing differences in the bioaccessibility of phenolics to be postulated. © 2019 Society of Chemical Industry.

Disease control efficacy of 32,33-didehydroroflamycoin produced by Streptomyces rectiviolaceus strain DY46 against gray mold of tomato fruit

Despite the efficacy of synthetic fungicides in controlling postharvest diseases, public concerns regarding chemical residues in food and an increase in drug-resistant strains of pathogens have led to a need for new agents to control postharvest diseases. The current study was performed to find control agents of microbial origin that are effective on gray mold of tomato fruits. We recently isolated Streptomyces rectiviolaceus DY46, which has antagonistic activity against various plant pathogenic fungi. The incidence of gray mold of tomato fruits was markedly reduced by 80.0% in tomatoes treated with the cell extract of Streptomyces rectiviolaceus DY46 compared with the control tomatoes. The active ingredient was purified from the cell extract of DY46 and identified to be 32,33-didehydroroflamycoin (DDHR). DDHR displayed MICs (minimal inhibitory concentrations) against the mycelial growth of various plant pathogenic fungi at concentrations of 8–64 mg L⁻¹. The incidence of gray mold in tomato fruits inoculated with conidial suspension (10⁴ conidia mL⁻¹) of Botrytis cinerea was markedly reduced by 88.9% in tomatoes treated with DDHR (100 mg L⁻¹) compared with the control. The DDHR residue in tomato fruit was significantly diminished 2 d after treatment. These results show that DDHR would be relatively safe for use as a postharvest fungicide.

Effect of Alginate and Chitosan Edible Coating Enriched with Olive Leaves Extract on the Shelf Life of Sweet Cherries (Prunus avium L.)

Edible film coatings are widely used as a protective barrier for the reduction of transpiration and respiration, therefore reducing the ripening process in fruits and vegetables and improving their quality. The influence of chitosan 1% and alginate 3% enriched with olive leaves extract (OLE) on the quality of sweet cherries was studied. Overall, the ripening process and the increase in anthocyanins were found to be delayed with the use of coating particularly those composed of chitosan in combination with OLE. Ascorbic acid and total phenolic contents were recorded with restricted loss at the end of 20 days of storage in both chitosan- and alginate-coated samples enriched with OLE. Higher values of antioxidant activity expressed as the percentage inhibition of DPPH were reported in correlation with phytochemical content. It could be concluded that chitosan and alginate coating enriched with OLE could be efficient for prolonging the shelf life of sweet cherries.

Application of edible coatings on fresh and minimally processed fruits: a review

Purpose

This paper aims to update with information about edible coating on minimally processed and fresh fruits, focussing on the composition, active ingredients, antimicrobial concentration and their effect on ripening rate, phytonutrients retention and shelf-life of fruits. In future, the data will be helpful for the processors to select the best coating material and its effective concentration for different fresh and minimally processed fruits.

Design/methodology/approach

Major scientific information was collected from Scopus, Web of Science, Mendeley and Google Scholar. Several key words such as postharvest, edible coating, phytonutrients, shelf-life enhancement, bioactive compounds, minimally processed fruits and antimicrobial compounds were used to find the data. Relevant information was collected by using 90 recent research and review articles.

Findings

The main findings of this comprehensive review are to improve the quality of fruits, to meet the next-generation food security needs. However, in the process of achieving the goal of improving quality of food produce, embrace of synthetic, non-biodegradable packaging materials have increased, creating serious pollution problem. Amidst several alternatives for replacement of synthetic packaging, the option of biodegradable films and coatings showed promising results.

Originality/value

The paper represents recent information about the edible coating used for the enhancement of shelf-life of fresh and minimally processed fruits.

Patulin, ergosterol and Howard mold count (HMC): Which one is the best quality indicator for tomatoes?

Ergosterol, an important constituent of fungal cell wall, was started to be used as a quality parameter for the tomatoes and derivatives instead of Howard mold count (HMC). In addition, patulin is another important microbiological quality indicator of molds such as Penicillium, Aspergillus, and Byssochlamys. In this study, it is aimed to identify the relationship between HMC, patulin, and ergosterol in juices produced from the tomatoes which has the surface rotten of 0% (sound), 25%, 50%, 75%, and 100%. As the rotten proportion increased, HMC, ergosterol, and patulin values increased. Linear correlations (r) between HMC, ergosterol, patulin, and rotten proportion were calculated as 0.99, 0.99, and 0.98, respectively. In addition, linear correlations between HMC and ergosterol (r = 0.95), HMC and patulin (r = 0.95) and ergosterol and patulin (r = 0.98) were found. In contrast, non-linear correlation between pH, brix and titratable acidity, and the rotten proportion was determined. PRACTICAL APPLICATIONS: The manuscript has provided the relationship between HMC, patulin, and ergosterol in juices produced from the tomatoes which have the surface rotten of 0% (sound), 25%, 50%, 75%, and 100%. Linear correlations between rotten proportions of tomatoes and HMC, ergosterol, patulin and between HMC and ergosterol, HMC and patulin, and ergosterol and patulin were determined in juices produced from rotten tomatoes. Patulin indicated correlation with HMC and ergosterol in juices produced from rotten tomatoes. In addition to HMC and ergosterol, patulin has great potential for the assessment of tomato products as associated with the rotten proportion.

Increasing of selenium content and qualitative parameters in tomato (Lycopersicon esculentum Mill.) after its foliar application

The effect of genotype and selenium foliar biofortification in the form of an aqueous solution of sodium selenate on the content of total carotenoids, vitamin C, total polyphenols and selenium content in the tomato fruits was studied.  Field experiment was held in the Botanical garden of the Slovak University of Agriculture in 2016. Seven determinant varieties of tomato in the two variants were observed. The results of experiments show that treatment of plants with the dose of Se concentration (150 g Se.ha-1) at the flowering stage significantly increased the total Se content in the in tomato fruits. Foliar application of selenium had a positive effect on the increase of total polyphenol. The influence of Se biofortification on the content of vitamin C and carotenoids was not detected. Selenium foliar fertilization in dosage 150 g.ha-1 is suitable way of tomato fruits enriching in polyphenols, without negative effect on other antioxidants content.

Sensory and functional quality characterization of protected designation of origin 'Piennolo del Vesuvio' cherry tomato landraces from Campania-Italy

Compositional characterization was performed on seven 'Pomodorino del Piennolo del Vesuvio' (PPV) tomato landraces, a signature product of Campania (Italy) threatened by genetic erosion. Characterization encompassed determinations of macro-minerals, soluble carbohydrates, starch, acidity, lycopene, polyphenols, anthocyanins, protein and free amino acids. Exceptionally high dry matter (13.0 ± 0.2%) and sugar content (101.3 ± 3.8 μmol g^-1 fw) and very low (0.007-0.009) Na/K ratio were invariably obtained across landraces, contrasted by significant variation in acidity (28.5-3.9 g kg^-1 dw). Giagiù, Acampora and Riccia San Vito differentiated by high polyphenols content (131.8 ± 2.5 mg 100 g^-1) while Acampora, Cozzolino and Fofò by high lycopene content (13.3 ± 10.6 mg 100 g^-1 fw). Glutamate, GABA and glutamine represented 65% of the 22 detected amino acids mean total content. Glutamate, linked to umami taste, was highest (19.2 µmol g^-1 fw) in Fofò. Our results will contribute towards the systematic documentation of sensory and functional quality profiles of an important collection of tomato landraces.

Phenotypic and Molecular Selection of a Superior Solanum pennellii Introgression Sub-Line Suitable for Improving Quality Traits of Cultivated Tomatoes

The Solanum pennellii Introgression Line (IL) population can be exploited to identify favorable alleles that can improve yield and fruit quality traits in commercial tomato varieties. Over the past few years, we have selected ILs that exhibit increased content of antioxidant compounds in the fruit compared to the cultivar M82, which represents the genetic background in which the different wild regions of the S. pennellii ILs were included. Recently, we have identified seven sub-lines of the IL7-3 accumulating different amounts of antioxidants in the ripe fruit. Since the wild region carried on chromosome 7 induces a low fruit production in IL7-3, the first aim of the present work was to evaluate yield performances of the selected sub-lines in three experimental fields located in the South of Italy. Another aim was to confirm in the same lines the high levels of antioxidants and evaluate other fruit quality traits. On red ripe fruit, the levels of soluble solids content, firmness, and ascorbic acid (AsA) were highly variable among the sub-lines grown in three environmental conditions, evidencing a significant genotype by environment interaction for soluble solids and AsA content. Only one sub-line (coded R182) exhibited a significantly higher firmness, even though no differences were observed for this trait between the parental lines M82 and IL7-3. The same sub-line showed significantly higher AsA content compared to M82, thus resembling IL7-3. Even though IL7-3 always exhibited a significantly lower yield, all the sub-lines showed yield variability over the three trials. Interestingly, the sub-line R182, selected for its better performances in terms of fruit quality, in all the trials showed a production comparable to that of the control line M82. A group of species-specific molecular markers was tested on R182 and on the parental genotypes in order to better define the wild genomic regions carried by the elite line R182. In these regions three candidate genes that could increase the level of AsA in the fruit were identified. In the future, the line R182 could be used as pre-breeding material in order to obtain new varieties improved for nutritional traits.

Analysis of Tomato Carotenoids: Comparing Extraction and Chromatographic Methods

Background: Tomatoes (Solanum lycopersicum) are an economically and nutritionally important crop colored by carotenoids such as lycopene and β-carotene. Market diversification and interest in the health benefits of carotenoids has created the desire in plant, food, and nutritional scientists for improved extraction and quantification protocols that avoid the analytical bottlenecks caused by current methods. Objective: Our objective was to compare standard and rapid extraction as well as chromatographic separation methods for tomato carotenoids. Method: Comparison was based on accuracy and the ability to discriminate between alleles and genetic backgrounds. Estimates of the contribution to variance in the presence of genetic and environmental effects were further used for comparison. Selections of cherry and processing tomatoes with varying carotenoid profiles were assessed using both established extraction and HPLC-diode array detector (HPLC-DAD) methods and rapid extraction and ultra-HPLC-DAD (UHPLC-DAD) protocols. Results: Discrimination of alleles in samples extracted rapidly (<5 min/sample) was similar to samples extracted using a standard method (10 min/sample), although carotenoid concentrations were lower due to reduced extraction efficiency. Quantification by HPLC-DAD (21.5 min/sample) and UHPLC-DAD (4.2 min/sample) were comparable, but the UHPLC-DAD method could not separate all carotenoids and isomers of tangerine tomatoes. Random effects modeling indicated that extraction and chromatographic methods explained a small proportion of variance compared with genetic and environmental sources. Conclusions: The rapid extraction and UHPLC-DAD methods could enhance throughput for some applications compared with standard protocols.

New insights in the control of antioxidants accumulation in tomato by transcriptomic analyses of genotypes exhibiting contrasting levels of fruit metabolites

Background

Tomato is an economically important crop with fruits that are a significant source of bioactive compounds such as ascorbic acid and phenolics. Nowadays, the majority of the enzymes of the biosynthetic pathways and of the structural genes controlling the production and the accumulation of antioxidants in plants are known; however, the mechanisms that regulate the expression of these genes are yet to be investigated. Here, we analyzed the transcriptomic changes occurring during ripening in the fruits of two tomato cultivars (E1 and E115), characterized by a different accumulation of antioxidants, in order to identify candidate genes potentially involved in the biosynthesis of ascorbic acid and phenylpropanoids.

Results

RNA sequencing analyses allowed identifying several structural and regulator genes putatively involved in ascorbate and phenylpropanoids biosynthesis in tomato fruits. Furthermore, transcription factors that may control antioxidants biosynthesis were identified through a weighted gene co-expression network analysis (WGCNA). Results obtained by RNA-seq and WGCNA analyses were further confirmed by RT-qPCR carried out at different ripening stages on ten cultivated tomato genotypes that accumulate different amount of bioactive compounds in the fruit. These analyses allowed us to identify one pectin methylesterase, which may affect the release of pectin-derived D-Galacturonic acid as metabolic precursor of ascorbate biosynthesis. Results reported in the present work allowed also identifying one L-ascorbate oxidase, which may favor the accumulation of reduced ascorbate in tomato fruits. Finally, the pivotal role of the enzymes chalcone synthases (CHS) in controlling the accumulation of phenolic compounds in cultivated tomato genotypes and the transcriptional control of the CHS genes exerted by Myb12 were confirmed.

Conclusions

By using transcriptomic analyses, candidate genes encoding transcription factors and structural genes were identified that may be involved in the accumulation of ascorbic acid and phenylpropanoids in tomato fruits of cultivated genotypes. These analyses provided novel insights into the molecular mechanisms controlling antioxidants accumulation in ripening tomato fruits. The structural genes and regulators here identified could also be used as efficient genetic markers for selecting high antioxidants tomato cultivars.

Electronic supplementary material

The online version of this article (10.1186/s12864-019-5428-4) contains supplementary material, which is available to authorized users.

Potential of Microalgae Carotenoids for Industrial Application

Microalgae cultivation, when compared to the growth of higher plants, presents many advantages such as faster growth, higher biomass productivity, and smaller land area requirement for cultivation. For this reason, microalgae are an alternative platform for carotenoid production when compared to the traditional sources. Currently, commercial microalgae production is not well developed but, fortunately, there are several studies aiming to make the large-scale production feasible by, for example, employing different cultivation systems. This review focuses on the main carotenoids from microalgae, comparing them to the traditional sources, as well as a critical analysis about different microalgae cultivation regimes that are currently available and applicable for carotenoid accumulation. Throughout this review paper, we present relevant information about the main commercial microalgae carotenoid producers; the comparison between carotenoid content from food, vegetables, fruits, and microalgae; and the great importance and impact of these molecule applications, such as in food (nutraceuticals and functional foods), cosmetics and pharmaceutical industries, feed (colorants and additives), and healthcare area. Lastly, the different operating systems applied to these photosynthetic cultivations are critically discussed, and conclusions and perspectives are made concerning the best operating system for acquiring high cell densities and, consequently, high carotenoid accumulation.

Comparative Chemical Compositions of Fresh and Stored Vesuvian PDO "Pomodorino Del Piennolo" Tomato and the Ciliegino Variety

The Vesuvian Piennolo cherry tomato (Lycopersicon esculentum Miller) (PdP) is an old and typical variety grown in the Campania region (Italy). PdP is referred to as a long-storage tomato due to its thick and coriaceous skin that allows long post-harvest storage and it has been granted Protected Designation of Origin (PDO) status since 2009. In this study, the chemical composition, focusing in particular on organic acids, antioxidant molecules and volatile compounds, were investigated in PdP and compared to another typical variety in Campania, the Ciliegino tomato (CIL). Chemical characterization was evaluated for both the CIL and PdP varieties during storage in the same environmental conditions until deterioration of 50% of the fruits; deterioration occurred in PdP after 6 months and in CIL tomatoes after 1 month. The results demonstrated variation in the chemical profiles of both varieties with storage length. Particularly, the PdP variety appears richer in antioxidants compounds (i.e., chlorogenic acids and lycopene) and organic acids (i.e., glutamic and malic acids) than does CIL. Additionally, both varieties display different profiles of volatile bioactive compounds and they are differently influenced by the storage time. The results indicate a typical chemical composition of this long-storage tomato closely linked to the geographic origin area.

Effect of alginate coating on the physico-chemical and microbial quality of pansies (Viola × wittrockiana) during storage

Edible flowers, such as pansies, are becoming more popular, but they are highly perishable. So, postharvest technologies are needed, being edible coatings a good alternative. Thus, the aim of this study was to evaluate the effect of alginate coating on physico-chemical and microbiological quality of pansies during cold storage (4 °C for 0, 7, 14, 21 days). Coated pansies maintained good appearance until 14 days of storage, 7 days more than uncoated ones. Flavonoids, hydrolysable tannins and monomeric anthocyanins, as well antioxidant activity, were higher in coated pansies when compared to uncoated ones, on all assayed storage times. Furthermore, after 14 days of storage, uncoated pansies presented microorganism counts higher than coated, namely yeasts and moulds, suggesting an effective barrier protection of the alginate coating treatment. In summary, alginate coating has potential for extending shelf-life and improving physico-chemical and microbiological quality of pansies.

Gene editing in tomatoes

Tomato is an effective model plant species because it possesses the qualities necessary for genetic and functional studies, but is also a food crop making what is learned more translatable for crop improvement when compared with other non-food crop models. The availability of genome sequences for many genotypes and amenability to transformation methodologies (Agrobacterium-mediated, direct DNA uptake via protoplasts, biolistics) make tomato the perfect platform to study the application of gene-editing technologies. This review includes information related to tomato transformation methodology, one of the necessary requirements for gene editing, along with the status of site-directed mutagenesis by TALENs (transcription activator-like effector nucleases) and CRISPR/Cas (clustered regularly interspaced short palindromic repeats and CRISPR-associated Proteins). In addition to the reports on proof-of-concept experiments to demonstrate the feasibility of gene editing in tomato, there are many reports that show the power of these technologies for modification of traits, such as fruit characteristics (ripening, size, and parthenocarpy), pathogen susceptibility, architecture (plant and inflorescence), and metabolic engineering. Also highlighted in this review are reports on the application of a recent CRISPR technology called base editing that allows the modification of one base pair in a gene sequence and a strategy that takes advantage of a geminivirus replicon for delivery of DNA repair template.

Effect of chitosan and alginate based coatings enriched with pomegranate peel extract to extend the postharvest quality of guava (Psidium guajava L.)

The influence of chitosan (1% w/v) and alginate (2% w/v) coatings in combination with pomegranate peel extract (PPE; 1% w/v) on quality of guavas (cv Allahabad safeda) were studied. Restricted changes were recorded in respiration rate, ripening index, and instrumental colour values in case of the coated samples as compared to the control for 20days at 10°C. Samples coated with chitosan enriched with PPE (CHE) proved to be the most effective treatment in maintaining the overall fruit quality. Ascorbic acid, total phenolics, total flavonoids contents and antioxidant activity were recorded with restricted losses of 29%, 8%, 12%, 12% (DPPH) and 9% (FRAP), respectively for CHE samples at the end of storage. A higher degree of correlation (r>0.918) was established between various phytochemicals and AOA. PPE enriched coatings was proved efficient in maintaining the quality of guavas during 20days of low temperature storage.

Portable Raman spectroscopy for an in-situ monitoring the ripening of tomato (Solanum lycopersicum) fruits

Ripening is one of the most important transformations that fruits and vegetables suffer, from an unripe to a ripe stage. In this study, it was followed up and analyzed the variations in the composition of tomato fruits at different ripening stages (green or unripe, orange or middle ripe, red or ripe and brown or overripe). The results obtained from the Raman measurements carried out showed a change in the composition of tomato fruits in the transit from green to brown. The analysis confirmed an increase of carotenoids from an unripe to a ripe stage of these fruits, being lycopene the characteristic carotenoid of the optimum ripe stage. The presence of chlorophyll and cuticular waxes decrease from the unripe to the ripe stage. Moreover, the relative intensity of phytofluene, a transition compound in the carotenoid biosynthetic pathway, is higher in the orange or middle ripening stage. The results obtained in-situ, without cutting and handling the tomato fruits, by means of a portable Raman spectrometer offered the same information that can be achieved using a more expensive and sophisticated confocal Raman microscope.

Carotenoids in fresh and processed tomato (Solanum lycopersicum) fruits protect cells from oxidative stress injury

BACKGROUND

Lipophilic antioxidants in tomato (Solanum lycopersicum) fruits exert important functions in reducing the risk of human diseases. Here the effect of thermal processing on the antioxidant activity of lipophilic extracts from the commercial tomato hybrid 'Zebrino' was analysed. Carotenoid content and lipophilic antioxidant activity were determined and the ability of tomato extracts in rescuing cells from oxidative stress was assessed.

RESULTS

Lipophilic antioxidant activity was completely retained after heat treatment and extracts were able to mitigate the detrimental effect induced by oxidative stress on different cell lines. Lycopene alone was able to rescue cells from oxidative stress, even if to a lower extent compared with tomato extracts. These results were probably due to the synergistic effect of tomato compounds in protecting cells from oxidative stress injury.

CONCLUSION

The current study provides valuable insights into the health effect of the dietary carotenoids present in fresh and processed tomato fruits. © 2016 Society of Chemical Industry.

Microwave flow and conventional heating effects on the physicochemical properties, bioactive compounds and enzymatic activity of tomato puree

BACKGROUND

Thermal processing causes a number of undesirable changes in physicochemical and bioactive properties of tomato products. Microwave (MW) technology is an emergent thermal industrial process that offers a rapid and uniform heating, high energy efficiency and high overall quality of the final product. The main quality changes of tomato puree after pasteurization at 96 ± 2 °C for 35 s, provided by a semi-industrial continuous microwave oven (MWP) under different doses (low power/long time to high power/short time) or by conventional method (CP) were studied.

RESULTS

All heat treatments reduced colour quality, total antioxidant capacity and vitamin C, with a greater reduction in CP than in MWP. On the other hand, use of an MWP, in particular high power/short time (1900 W/180 s, 2700 W/160 s and 3150 W/150 s) enhanced the viscosity and lycopene extraction and decreased the enzyme residual activity better than with CP samples. For tomato puree, polygalacturonase was the more thermo-resistant enzyme, and could be used as an indicator of pasteurization efficiency.

CONCLUSION

MWP was an excellent pasteurization technique that provided tomato puree with improved nutritional quality, reducing process times compared to the standard pasteurization process. © 2016 Society of Chemical Industry.

The Choice of Canned Whole Peeled Tomatoes is Driven by Different Key Quality Attributes Perceived by Consumers Having Different Familiarity with the Product

Canned whole peeled tomatoes are a premium tomato product; however, no information is available about the key intrinsic and extrinsic quality attributes perceived by consumers when buying this product. This research considered consumers differing in the level of familiarity with peeled tomatoes, that is, knowledge, frequency of consumption, and availability of this product, on 3 markets: Chile (low), The Netherlands (medium), and Italy (high). The perceptions and preferences of each group were studied using first focus groups and subsequently conjoint analysis in order to identify the key quality attributes leading their preferences for this product. Focus groups identified 7 intrinsic attributes (color, packing medium, tomato consistency, acidity level, sweetness level, extra ingredients, and intensity of product taste), and 5 extrinsic attributes (packaging material, product type, country of origin, brand, and label design). Significant variations according to the familiarity were found. The conjoint analyses showed that color of tomatoes was the most important intrinsic quality attribute for all groups, while packaging material was the most important extrinsic quality attribute for Chileans and Dutch, being a glass container or a can with easy open the preferred packaging for respective groups. In contrast, country of origin was the most important parameter for Italians. We concluded that intrinsic and extrinsic attributes were strongly influenced by the degree of familiarity with canned whole peeled tomatoes.

Nutrient Intake and Depression Symptoms in Spanish Children: The ANIVA Study

The aim of this study was to examine the relationship between nutritional intake and depressive symptoms in Valencian schoolchildren. The ANIVA (Antropometria y Nutricion Infantil de Valencia) study is a descriptive cross-sectional study. During academic year 2013–2014, 710 schoolchildren aged 6–9 years were selected from eleven primary schools in Valencia (Spain). Children’s dietary intake was measured on three-day food records, completed by parents/guardians; children completed the 20-item Center for Epidemiologic Studies Depression Scale for Children (CES-DC) Questionnaire to measure depressive symptoms. Weight, height, and body mass index (BMI), and z-scores were evaluated in all subjects. Nutrient adequacy was assessed using Spanish dietary recommended intakes (DRIs); 20.70% of the sample presented depressive symptoms. We identified a positive association between children with depressive symptoms and non-depressive symptoms for thiamin, vitamin K, and bromine (p < 0.05), and a negative association for protein, carbohydrates, pantothenic acid, biotin, vitamin B₁₂ and E, zinc, manganese, cobalt, and aluminum (p < 0.05). Statistically significant differences were found between both groups according to the DRIs for intakes of total energy (p = 0.026), fiber (p < 0.001), vitamin C (p < 0.001), vitamin E (p = 0.004), magnesium (p = 0.018), and iron (p = 0.013). Our results demonstrated that carbohydrates were the most closely associated factor with depressive symptoms, and highlight the potential significant public health implications of inadequate nutritional intake on schoolchildren’s mental health.

Vitamin E Content and Composition in Tomato Fruits: Beneficial Roles and Bio-Fortification

Several epidemiological studies have demonstrated that high vitamin E intakes are related to a reduced risk of non-communicable diseases, while other dietary antioxidants are not, suggesting that vitamin E exerts specific healthy functions in addition to its antioxidant role. In this regard, tomato (Solanum lycopersicum), one of the most consumed vegetables of the whole world population, is an important source of both tocopherols and tocotrienols. However, vitamin E content may strongly depend on several biotic and abiotic factors. In this review we will debate the elements affecting the synthesis of tocopherols and tocotrienols in tomato fruit, such as environmental conditions, genotype, fruit maturity level, and the impact of classical processing methods, such as pasteurization and lyophilization on the amount of these compounds. In addition we will analyze the specific vitamin E mechanisms of action in humans and the consequent functional effects derived from its dietary intake. Finally, we will examine the currently available molecular techniques used to increase the content of vitamin E in tomato fruit, starting from the identification of genetic determinants and quantitative trait loci that control the accumulation of these metabolites.

Olive oil enriched in lycopene from tomato by-product through a co-milling process

The aim of this investigation was to produce an olive oil (OO) naturally enriched with antioxidants, recovering carotenoids, in particular lycopene, using an industrial by-product of tomato seeds and skin. For this purpose, a technological process in a low-scale industrial plant to co-mill olives and tomato by-product in de-frosted or freeze-dried forms was applied and studied with respect to control samples. Preliminary results obtained from two different experiments were carried out by 40 kg of cultivar Correggiolo olives and 60 kg of olive blends from different cultivars. In both the experiments, the co-milling showed significant enrichment in carotenoids, especially in lycopene (mean values of 5.4 and 7.2 mg/kg oil from defrosted and freeze-dried by-products, respectively). The experimental results demonstrated the possibility to obtain a new functional food naturally enriched in antioxidant compounds, which might be marketed as "OO dressing enriched in lycopene" or "condiment produced using olives and tomato by-product".

Qualitative and quantitative characteristics of Serbian tomato varieties grown in conditions of Slovak republic

The aim of submitted article was to estimate qualitative and quantitative characteristic of Serbian tomato varieties grown in conditions of Slovak republic and to compare the results with control tomato variety and evaluate their potential for the Slovak market. There were included 6 Serbian tomato varieties: ´Fantom VFCTm F1´, ´Marathon ASVF F1´, ´Honey Heart VF F1´, ´Uragan SVF F1´, ´Kazanova F1 VF´, ´Dinka F1´ and ´Tornado F1´ in control variant, which is wide spread in Slovak tomato production. As qualitative characteristic for every variety total yields (in kg) per every plant, total number of harvested fruits (in pieces for each plant) and average weight of one fruit in kg were evaluated. In Department of vegetable growing laboratory qualitative characteristics in case of all chosen tomato varieties were estimated (included firmness of fruits, total carotenoids estimation, ascorbic acid estimation). Serbian varieties reached lower total yields per plant. From the ´fruit weight´ point of view they created more or less homogenous group of bigger and heavier fruits in comparison with ´Tornado F1´ and statistically significant homogenous group when focusing on total number of fruits per plant in comparison with ´Tornado F1´ variety. Differences between control variant and chosen Serbian varieties were even more considerable in case of qualitative characteristics, where ´Tornado F1´ reached the lowest values in case of all observed characteristics - firmness of fruits, total carotenoids and ascorbic acid content. According to increasing importance of antioxidants in human diet, all tested Serbian varieties appeared to be very interesting for Slovak consumers from following both qualitative and quantitative characteristics.

Protection against chemotaxis in the anti-inflammatory effect of bioactives from tomato ketchup

The consumption of tomato products has been associated with a decreased risk for chronic inflammatory diseases. In this study, the anti-inflammatory potential of tomato ketchup was evaluated by studying the effect of tomato ketchup extracts and bioactives from tomato ketchup on human monocytes and vascular endothelial cells (HUVEC). HUVEC were pre-treated for 1 h with either individual bioactives (7.5 µM lycopene, 1.4 µM α-tocopherol or 55 µM ascorbic acid) or a combination of these three compounds, or with the hydrophilic or lipophilic tomato ketchup extracts or with the two extracts combined. After the pretreatment, the cells were washed and challenged with TNF-α (10 ng/ml) for 6 h. The medium was used for the determination of the release of cytokines and the chemotaxis of monocytes. Inflammatory protein expression and production were assayed with real-time RT-PCR and ELISA. It was found that tomato ketchup extracts significantly reduced gene expression and release of the pro-inflammatory cytokines TNF-α and IL-8 in HUVEC after the inflammatory challenge, whereas the release of the anti-inflammatory cytokine IL-10 was increased. Chemotaxis was effectively impeded as demonstrated by a reduced monocyte migration. This effect correlated with the reduction of IL-8 production in the presence of the test compounds and extracts. The results consistently emphasize the contribution of lycopene to the anti-inflammatory effect of tomato ketchup. Other compounds in tomato ketchup such as α-tocopherol and ascorbic acid appeared to strengthen the anti-inflammatory effect of lycopene. The tomato ketchup extracts subtly interfered with several inflammatory phases that inhibit chemotaxis. Such a pleotropic mode of action exemplifies its potential mitigation of diseases characterized by prolonged low grade inflammation.

The role of traditional varieties of tomato as sources of functional compounds

BACKGROUND

Traditional varieties of tomato, usually associated with excellent organoleptic quality, are increasingly appreciated in European quality markets. A collection of 126 populations of 16 traditional varieties from the east of Spain (a secondary diversity center for tomato) have been evaluated over 2 years in order to determine their potential value as sources of functional compounds, including ascorbic acid, lycopene, β-carotene and total phenolic content.

RESULTS

Population and population × year interaction significantly affected lycopene and ascorbic acid contents, while year effect was also significant for β-carotene. Despite finding some global trends in certain varieties concerning their functional value, high levels of variation have been found at the intra-varietal level. Populations with high levels of the compounds analysed have been found, as well as different levels of intra-population and inter-year variation. Maximum mean contents for both years have reached 308 mg kg(-1) ascorbic acid, 130 mg kg(-1) lycopene, 30 mg kg(-1) β-carotene and 89 mg caffeic acid 100 g(-1) total phenolic contents, though it is difficult to identify accessions with joint high values of the three compounds.

CONCLUSION

These results open the possibility to promote traditional materials as sources of functional compounds, thus strengthening their quality niches and consolidating their price premium. Additionally, these materials could also be used in breeding programs for quality.