Tomato as a Source of Carotenoids and Polyphenols Targeted to Cancer Prevention

NMR Metabolomics as an Effective Tool To Unravel the Effect of Light Intensity and Temperature on the Composition of the Marine Microalgae Isochrysis galbana

NMR spectroscopy coupled with multivariate data analysis techniques was applied to obtain meaningful information about nontargeted metabolic changes on  Isochrysis galbana upon acclimation to different environmental conditions at indoor lab-scale. The effects of temperature (from 15 to 30 °C) and incident irradiance (from 250 to 1600 μmol m^-2 s^-1) at a constant dilution rate of 0.3 h^-1 were evaluated. High irradiances stimulated a decrease of chlorophyll a, fucoxanthin and amino acids content, and the conversion of polar fatty acids (PLs, GLs, DGDGs, SGDGs) to neutral fatty acids (saturated and unsaturated). High temperatures together with high irradiances decreased PUFAs concentration, including omega-3 fatty acids. Under low irradiance and temperature organic osmolytes (homarine, DMSP, GBT, and glycerol), and sugars (glucose, trehalose, and galactose) were also reduced.

Get the Balance Right: ROS Homeostasis and Redox Signalling in Fruit

Plant central metabolism generates reactive oxygen species (ROS), which are key regulators that mediate signalling pathways involved in developmental processes and plant responses to environmental fluctuations. These highly reactive metabolites can lead to cellular damage when the reduction-oxidation (redox) homeostasis becomes unbalanced. Whilst decades of research have studied redox homeostasis in leaves, fundamental knowledge in fruit biology is still fragmentary. This is even more surprising when considering the natural profusion of fruit antioxidants that can process ROS and benefit human health. In this review, we explore redox biology in fruit and provide an overview of fruit antioxidants with recent examples. We further examine the central role of the redox hub in signalling during development and stress, with particular emphasis on ascorbate, also referred to as vitamin C. Progress in understanding the molecular mechanisms involved in the redox regulations that are linked to central metabolism and stress pathways will help to define novel strategies for optimising fruit nutritional quality, fruit production and storage.

Optimization of extraction yield, flavonoids and lycopene from tomato pulp by high hydrostatic pressure-assisted extraction

Tomato pulp is a useful source of antioxidants, which can be extracted by high hydrostatic pressure (HHPE). This study aimed to optimize the individual and interactive effect of operating high pressure and solvent polarity (solvent mixture) on yield extraction, flavonoid and lycopene content from tomato pulp (Solanum lycopersicum) by using response surface methodology (RSM). The results showed that the selected factors (high pressure and solvent mixture) have a significant influence on extraction yield, flavonoid and lycopene content. Extraction at 450 MPa and 60% hexane concentration in the solvent mixture was considered the optimal HHPE condition since it provided the maximum extraction yield (8.71%), flavonoid (21.52 ± 0.09 mg QE/g FW) and lycopene content (2.01 ± 0.09 mg QE/100 g FW). Therefore, HHPE could be a useful tool improve the extraction and release of potentially health-related compounds while providing information on the cumulative effect of solvent polarity and high-pressure extraction on antioxidant compounds of fruits.

Fermentation: A Boon for Production of Bioactive Compounds by Processing of Food Industries Wastes (By-Products)

A large number of by-products or wastes are produced worldwide through various food industries. These wastes cause a serious disposable problem with the environment. So, now a day's different approaches are used for alternative use of these wastes because these by-products are an excellent source of various bioactive components such as polyphenols, flavonoids, caffeine, carotenoids, creatine, and polysaccharides etc. which are beneficial for human health. Furthermore, the composition of these wastes depends on the source or type of waste. Approximately half of the waste is lignocellulosic in nature produced from food processing industries. The dissimilar types of waste produced by food industries can be fortified by various processes. Fermentation is one of the oldest approaches and there are three types of fermentation processes that are carried out such as solid state, submerged and liquid fermentation used for product transformation into value added products through microorganisms. Selections of the fermentation process are product specific. Moreover, various studies were performed to obtain or fortified different bioactive compounds that are present in food industries by-products or wastes. Therefore, the current review article discussed various sources, composition and nutritive value (especially bioactive compounds) of these wastes and their management or augmentation of value-added products through fermentation.

The Chemistry behind Tomato Quality

Tomato is one of the most widely consumed fresh vegetables in the industrialized world and an important source of healthy constituents of the human diet. Despite the unique flavor characteristics of tomatoes, which make them extremely valuable in cooking, and their recognized beneficial role in the diet, the quality of tomato was traditionally only considered in connection to external appearances. As it happened with other highly requested crops, breeding programs of tomato focused their efforts on developing new varieties with higher yields and stress resistance, with better uniformity in fruit size, brighter color and prolonged shelf life. The downside of these strategies was that organoleptic features and nutritional value were often neglected, with a detrimental effect on commercial tomatoes. Over the last years, there has been an increase in consumers’ demand for tasty and healthy products. This aspect, paired with novel and multidisciplinary approaches to tomato research, allowed both sensory and nutritional qualities to be reconsidered as valuable parameters in breeding. In this review we describe the main chemical constituents of tomato, focusing on the flavor compounds (both volatile and non-volatile compounds) and secondary metabolites. Particular attention is paid to their beneficial effects on human health and their relevance to the overall quality of tomato.

Dietary Carotenoids Intake and the Risk of Gastric Cancer: A Case-Control Study in Korea

Although the incidence of gastric cancer (GC) has declined, it remains the second most common cancer in Korea. As a class of phytochemicals, carotenoids are fat-soluble pigments that are abundant in fruits and vegetables and have health-promoting properties, including cancer prevention effects. This case-control study investigated the effects of total dietary carotenoids, dietary carotenoid subclasses (α-carotene, β-carotene, β-cryptoxanthin, lutein/zeaxanthin, and lycopene), and foods contributing to the dietary intake of each carotenoid on the risk of GC. Four hundred and fifteen cases and 830 controls were recruited from the National Cancer Center Hospital in Korea between March 2011 and December 2014. A significant inverse association between total dietary carotenoids and GC risk was observed among women (odds ratio (OR) 0.56, 95% confidence interval (CI) 0.32⁻0.99). A higher intake of dietary lycopene was inversely associated with GC risk overall in the subjects (OR 0.60, 95% CI 0.42⁻0.85, p for trend = 0.012), men (OR 0.60, 95% CI 0.39⁻0.93), and women (OR 0.54, 95% CI 0.30⁻0.96, p for trend = 0.039). This significant association between dietary lycopene intake and GC risk was also observed in the subgroups of Helicobacter pylori (H. pylori)-positive subjects and those who had ever smoked. Among the major contributing foods of dietary lycopene, consumption of tomatoes and tomato ketchup was inversely associated with GC risk in the overall subjects, men, and women. Based on our findings, a higher intake of dietary lycopene and contributing foods of lycopene (tomatoes and tomato ketchup) may be inversely associated with the risk of GC.

Bioactivities of phytochemicals present in tomato

Tomato is a wonder fruit fortified with health-promoting phytochemicals that are beneficial in preventing important chronic degenerative disorders. Tomato is a good source of phenolic compounds (phenolic acids and flavonoids), carotenoids (lycopene, α, and β carotene), vitamins (ascorbic acid and vitamin A) and glycoalkaloids (tomatine). Bioactive constituents present in tomato have antioxidant, anti-mutagenic, anti-proliferative, anti-inflammatory and anti-atherogenic activities. Health promoting bioactivities of tomatoes make them useful ingredient for the development of functional foods. Protective role of tomato (lycopene as a potent antioxidant) in humans against various degenerative diseases are known throughout the world. Intake of tomato is inversely related to the incidence of cancer, cardiovascular diseases, ageing and many other health problems. Bioavailability of phytoconstituents in tomato is generally not affected by routine cooking processes making it even more beneficial for human consumption. The present review provides collective information of phytochemicals in tomato along with discussing their bioactivities and possible health benefits.

Role of NRF2 in protection of the gastrointestinal tract against oxidative stress

The gastrointestinal tract is exposed to a variety of noxious factors, such as Helicobacter pylori, nonsteroidal anti-inflammatory drugs, gastric acid, ischemia-reperfusion, and mental stresses. Theses stressors generate free radicals within gastrointestinal tissues, causing organ injury and functional disturbance. Although the gastrointestinal tract can withstand such oxidative stresses to some extent by enhancing its antioxidant system via nuclear factor erythroid 2-related factor 2-Kelch-like erythroid cell-derived protein with CNC homology-associated protein 1-mediated pathways, acute or chronic exposure to oxidative stress can cause several gastrointestinal tract disorders, such as inflammation, ulcers, cancers, and various functional disturbances. Recent studies have demonstrated that some natural compounds and drugs can upregulate the nuclear factor erythroid 2-related factor 2-mediated antioxidant system, ameliorating or preventing these disorders. Although these compounds may be useful as chemopreventive agents, sufficient evidence for their clinical efficacy has not yet been provided. In addition, it is important to note that excessive nuclear factor erythroid 2-related factor 2 stimulation can be harmful to human health, especially from the standpoint of tumor biology.

Transcriptome profiling of genes involving in carotenoid biosynthesis and accumulation between leaf and root of carrot (Daucus carota L.)

Carrot provides abundant carotenoid for human diet and is one of the most widely cultivated root vegetables in the world. However, the absence of the tissue-specific transcriptome of carrots hampers the investigation of the association of secondary metabolic mechanism with the different tissue types. In this study, we obtained 46,119,008/48,414,508 raw reads and 45,394,846/47,887,648 clean reads from the carrot leaf and root, respectively. Moreover, α- and β-carotene were found to accumulate in both tissues. Then, using Trinity assembly into contigs and mapped back to contigs, these reads were assembled to 56,267 and 62,427 leaf and root unigenes, respectively, after Ns removal and paired-end extension. In addition, a total of 18,354 DEGs were found between the carrot leaf and root unigenes, and 99 of these DEGs were found to be involved in carotenoid biosynthesis as revealed by integrated function annotation. In the carotenoid pathway DEGs, DcPSY1, DcZ-ISO, DcCISO2, DcLBCY, DcLECY, DcZEP1, DcZEP2, DcVDE1, DcVDE2, DcNSY1, DcNSY2, DcA8H-CYP707A1.2, DcAAO3a, DcCCD4, and DcMAX1 were expressed dramatically in the carrot leaf compared with in the root. This result was consistent with the results from the quantitative real-time PCR analysis of DEG expression profiles. Moreover, 67 more carotenoid biosynthesis-related genes were found in this transcriptome database. Most of these DEGs were up-regulated in the carrot leaf compared with those in the root. The expression of DEGs may be related to the higher carotenoid pathway flux in the carrot leaf than in the root. These results will help to further understand the carotenoid biosynthesis in carrot.

Antioxidant Phytochemicals in Fresh Produce: Exploitation of Genotype Variation and Advancements in Analytical Protocols

Horticultural commodities (fruit and vegetables) are the major dietary source of several bioactive compounds of high nutraceutical value for humans, including polyphenols, carotenoids and vitamins. The aim of the current review was dual. Firstly, toward the eventual enhancement of horticultural crops with bio-functional compounds, the natural genetic variation in antioxidants found in different species and cultivars/genotypes is underlined. Notably, some landraces and/or traditional cultivars have been characterized by substantially higher phytochemical content, i.e., small tomato of Santorini island (cv. "Tomataki Santorinis") possesses appreciably high amounts of ascorbic acid (AsA). The systematic screening of key bioactive compounds in a wide range of germplasm for the identification of promising genotypes and the restoration of key gene fractions from wild species and landraces may help in reducing the loss of agro-biodiversity, creating a healthier "gene pool" as the basis of future adaptation. Toward this direction, large scale comparative studies in different cultivars/genotypes of a given species provide useful insights about the ones of higher nutritional value. Secondly, the advancements in the employment of analytical techniques to determine the antioxidant potential through a convenient, easy and fast way are outlined. Such analytical techniques include electron paramagnetic resonance (EPR) and infrared (IR) spectroscopy, electrochemical, and chemometric methods, flow injection analysis (FIA), optical sensors, and high resolution screening (HRS). Taking into consideration that fruits and vegetables are complex mixtures of water- and lipid-soluble antioxidants, the exploitation of chemometrics to develop "omics" platforms (i.e., metabolomics, foodomics) is a promising tool for researchers to decode and/or predict antioxidant activity of fresh produce. For industry, the use of optical sensors and IR spectroscopy is recommended to estimate the antioxidant activity rapidly and at low cost, although legislation does not allow its correlation with health claims.

Processed and raw tomato consumption and risk of prostate cancer: a systematic review and dose-response meta-analysis

BACKGROUND

Prostate cancer (PCa) is the second most frequently diagnosed cancer among men worldwide. Many epidemiological studies have found an inverse association between increased tomato consumption and PCa risk. This study aims to determine the associations between consumption of various types of tomato products and PCa risk and to investigate potential dose-response relationships.

METHODS

We conducted a systematic review and dose-response meta-analysis of dietary tomato in relation to PCa. Eligible studies were published before April 10, 2017 and were identified from PubMed, Web of Science, and the Cochrane Library. We estimated pooled risk ratios (RRs) and 95% confidence intervals (CI) using random and fixed effects models. Linear and nonlinear dose-response relationships were also evaluated for PCa risk.

RESULTS

Thirty studies related to tomato consumption and PCa risk were included in the meta-analysis, which summarized data from 24,222 cases and 260,461 participants. Higher total tomato consumption was associated with a reduced risk of PCa (RR = 0.81, 95% CI: 0.71-0.92, p = 0.001). Specifically, tomato foods (RR = 0.84, 95% CI: 0.72-0.98, p = 0.030) and cooked tomatoes and sauces (RR = 0.84, 95% CI: 0.73-0.98, p = 0.029) were associated with a reduced risk of PCa. However, no associations were found for raw tomatoes (RR = 0.96, 95% CI: 0.84-1.09, p = 0.487). There was a significant dose-response association observed for total tomato consumption (p = 0.040), cooked tomatoes and sauces (p < 0.001), and raw tomatoes (p = 0.037), but there was not a significant association with tomato foods (p_linear = 0.511, p_nonlinear = 0.289).

CONCLUSIONS

Our data demonstrate that increased tomato consumption is inversely associated with PCa risk. These findings were accompanied with dose-response relationships for total tomato consumption and for cooked tomatoes and sauces. Further studies are required to determine the underlying mechanisms of these associations.

SolCyc: a database hub at the Sol Genomics Network (SGN) for the manual curation of metabolic networks in Solanum and Nicotiana specific databases

Database URL

https://solgenomics.net/tools/solcyc/.

Assessment of biochar and hydrochar as minor to major constituents of growing media for containerized tomato production

BACKGROUND

Chars are emerging materials as constituents of growth media. However, chars of different origin differ in their characteristics and more studies are needed to ratify them for such a role. The characteristics of coir mixed with 0%, 10%, 25%, 50%, 75%, and 100% (v/v) of two biochars, from forest waste (BCH-FW) and from olive mill waste (BCH-OMW), and one hydrochar, from forest waste (HYD-FW), and their effects on growth, yield and fruit quality of two tomato cultivars (Gransol RZ and Cuarenteno) were assessed.

RESULTS

Chars negatively affected plant growth and yield but not fruit quality. The effect was related to the char dose and was larger in HYD-FW and BCH-FW than in BCH-OMW, despite the high salinity of the latter, and more acute in Cuarenteno than in Gransol RZ. The results were discussed on the basis of the large particle size of BCH-FW, which could have caused low nutrient solution retention and, hence, reduced plant nutrient uptake, and the high water-holding capacity, poor aeration and large CO₂ emission of HYD-FW, which could lead to root anoxia.

CONCLUSION

BCH-OMW can be used at high proportion in media for tomato cultivation. The use of BCH-FW at a high proportion might be taken into consideration after adjusting particle size, yet this needs additional assays. HYD-FW is inadequate for soilless containerized tomato cultivation. © 2017 Society of Chemical Industry.

Polyphenol and l-ascorbic acid content in tomato as influenced by high lycopene genotypes and organic farming at different environments

The accumulation of polyphenols and l-ascorbic acid was evaluated under conventional (integrated pest management, IPM) and organic farming, as means to increase the accumulation of chemoprotective compounds. The effect of genotype was considerably higher than the growing system, in fact it is determining. 'Kalvert', a high-lycopene cultivar, outstood for the accumulation of most polyphenols, though low-carotenoid cultivars with high accumulation were also detected. Organic farming significantly increased the levels of caffeic acid by 20%, but reduced those of ferulic acid and naringenin by 13% and 15% respectively. A strong interaction with the environment was detected: in Navarra the differences were limited, while in Extremadura lower contents of ferulic acid and higher contents of chlorogenic acid and rutin were found in organic farming for certain cultivars. The effect of organic farming on l-ascorbic acid was dependent on cultivar and environment and it only led to an increase in Extremadura by 58%.