The present study was conducted to evaluate recently developed pungent and unpungent red pepper varieties for paprika production with respect to carotenoid and tocopherol composition and content. Varieties with outstanding traits were cultivated using various methods to determine the optimal conditions for maximizing bioactive component levels. The biologically ripe fruits of these varieties were stored under ambient conditions to initiate postharvest overripening. Carotenoids and tocopherols were analyzed using recent HPLC methods. The different varieties of pungent pepper differed significantly in the levels of carotenoid groups and tocopherols. Among pungent breeds, Hetényi Triász (HET-T), CF5, and Uniring (UNIR) showed the highest levels of total carotenoids (1967.39 ± 260.35, 1642.72 ± 67.41, and 1609.07 ± 524.52 µg g−1, respectively). The highest amounts of provitamin A (187.60 ± 8.19 µg g−1) were recorded in the CF5 variety. As regards tocopherols, the highest concentration (547.09 ± 44.20 µg g−1) was recorded for CF5, with no significant differences among the studied varieties. However, the content of vitamin E was significantly higher in CF1 and CF5 than in HET-T and UNIR. Notably, under organic farming conditions, the carotenoid content in UNIR was significantly lower than in the direct-sowing and seedling-transplantation modes. Organic farming of UNIR resulted in lower levels of all carotenoid groups compared with other cultivation modes, particularly conventional seedling transplantation. The indoor cultivation of the unpungent Borbási genotype did not significantly improve the carotenoid content, particularly the total red xanthophylls. Ambient postharvest overripening led to a substantial increase, up to 3-fold, in carotenoid group content in both pungent and non-pungent genotypes. The average value for the total carotenoid content increased from 5005.7 to 8208.3 µg g−1 in unpungent varieties and from 1896.4 to 3426.8 µg g−1 in pungent varieties. For tocopherols, overripening had a slightly positive effect on total tocopherol (from 1375.3 to 1594.7 µg g−1) and esterified forms of vitamin E in pungent breeds with a significantly high increase from 532.0 to 823.7 µg g−1. In conclusion, postharvest overripening is indispensable for obtaining paprika products with an outstanding content of bioactive compounds, particularly red carotenoid diesters. Based on carotenoid content and response to overripening of red and total carotenoids, the UNIR and Borbási varieties are superior to other pungent and unpungent genotypes, respectively. The positive impact of postharvest overripening on carotenoid and tocopherol levels depended mainly on genetic factors.
The assessment of water stress levels in plants should be an essential part of precise irrigation management, and a good and quick method is useful in plant phenotyping. There are many options for this task, but the effectiveness varies between crop species and environments. Apparently open field applications face the most difficulties. This study aimed to test a large number of vegetation indices (VIs) and multivariate models based on hyperspectral reflectance data (325–1075 nm) regarding their correlation and prediction abilities to leaf stomatal conductance, relative water content (RWC), and detailed chlorophyll and carotenoid components.Data of the abovementioned variables was collected during three consecutive growing seasons in processing tomato cultivated under different water supply regimes to provide data with varying water stress levels. Then the relation of the measured variables to 226 VIs was tested created according to the formulas collected in the Index DataBase, established within the IDB Project. New VIs were also developed derived from the most important variables of the ML algorithms, customised to tomato water stress assessment. Standard normal variate and its combination with Savitzky-Golay first derivative were used for pre-processing the spectra, and principal component regression (PCR), partial least squares regression (PLSR), elastic net (ENET), support vector regression (SVR), random forest (RF) and extreme gradient boosting (XGB) algorithms were tested.The newly developed indices outperformed the existing formulas, except in the case of β-carotene. The most reliable index was developed for RWC estimation; that was the difference of the reflectance on the 986 and 701 nm wavelengths.The ENET and SVR algorithms produced the best models depending on the pre-processing method. The blue, near-infrared (NIR), and green regions, respectively, were the most important regarding all models according to the variable importance analysis. The model with the best metrics was developed for chlorophyll-a (R2=0.82, nRMSE=11%, RPIQ=2.41), followed by RWC (R2=0.72, nRMSE=14%, RPIQ=2.53).
Sweet cherry (Prunus avium L.) is a rich source of phenolic compounds, including anthocyanins and polyphenols, which contribute to fruit quality and nutritional value. However, their distribution across tissues (flesh and skin) and stability under different postharvest freezing treatments remain poorly understood. This study characterized the phenolic profiles of 14 sweet cherry genotypes in different tissues (whole fruit, flesh, and skin) and assessed the effects of freezing storage conditions on compound stability using high-performance liquid chromatography. Results revealed pronounced tissue-specific patterns: most phenolic compounds, particularly total anthocyanins, neochlorogenic acid, rutin, and chlorogenic acid, were more than twofold higher in the skin than in the flesh. Substantial genotype-dependent variability was observed, with certain cultivars exhibiting markedly higher phenolic concentrations. Immediate freezing in liquid nitrogen preserved significantly higher levels of phenolics compared to delayed freezing at -70 °C, where several compounds showed considerable degradation, especially in separated flesh samples. Anthocyanin content increased strongly with pigmentation intensity, with darker-coloured genotypes showing up to a 50-fold higher concentration than lighter-coloured types. Molecular analysis identified MYB-associated polymorphisms corresponding to differences in phenolic accumulation and fruit pigmentation. These findings demonstrate that genotype and tissue type are key determinants of phenolic composition, while immediate postharvest freezing is essential for preserving bioactive compounds. The combined biochemical and molecular approach provides novel insight into the regulation and stability of phenolic compounds in sweet cherry and supports the selection of cultivars with enhanced nutritional quality and improved postharvest performance.
The effect of climate and genetic factors on fat-soluble phytochemicals of four pungent peppers were investigated. The carotenoids and tocopherols were determined by recent chromatographic methods. Low temperature and high precipitation promoted synthesis of yellow-coloured carotenoid groups and provitamin A, while the climate with high temperature low precipitation, were favourable for the synthesis of the red xanthophylls. The provitamins A increased by 7–81 % when the precipitation was substantially high and the temperature low in 2022. The total red carotenoids were lower by 4–35 % as compared to their content at the first harvest of the same season. In 2023, provitamins A were lower by 45–75 % and total red xanthophylls higher by 7–32 % due to change in climate conditions towards high precipitation and low temperature. The seasonal variation in climate had a strong significant impact on the tocopherol content of peppers. The climate variation between the two seasons resulted in an increase of 12–44 % and 46–72 % for the SZ178 and BHJ respectively. The genotypes differed significantly in phytochemical response to climate changes. In conclusion, the SZ178 and BHJ varieties are recommended due to their adaptation to climate changes. In future, genetic studies should consider the interaction between abiotic and genetic factors
Pungent red peppers and chilis are healthy foods and crucial ingredients of modern diets due to their content of bioactive phytochemicals such as carotenoids, tocopherols, capsaicinoids, polyphenols, and vitamin C. The production of pungent peppers with outstanding nutritional properties is influenced by genetic factors and their interaction with the environments where they are cultivated. This study was conducted to investigate the effects of genotype and climate conditions on the response of capsaicinoids and vitamin C. The extracts of pungent materials and vitamin C were separated and qualitatively determined by HPLC alone or hyphenated with mass spectroscopy. Four genotypes were selected and cultivated under traditional agricultural practices in southern Hungary. The yield properties and the contents of capsaicinoids and vitamin C were significantly influenced by genetic factors and, to a high extent, by the interaction between genotype × environment. The highest yield of 2.86 ± 0.59 kg/m2 was recorded for the CS variety. The yield was significantly decreased under high precipitation and low air temperature. The highest concentration of capsaicin of 1586–1734 µg/g dwt was found in the BHJ variety. The lowest level of 514 µg/g dwt of capsaicin was determined in the CS variety, in which the content significantly increased to 772 µg/g dwt with the increase in rainfall and decrease in air temperature in the warmer season of 2022. In most cultivars examined, capsaicin content negatively responded to the change of the climate toward higher precipitation and lower temperature except for SZ178, in which the concentration of capsaicinoids stayed insignificantly varied. The amount of vitamin C ranged between 570 and 135 µg/g dwt, with the highest content being in the BHJ and the lowest in the REK variety. In most varieties except the REK, vitamin C positively responded to a high and negatively to the reduced levels of precipitation. In conclusion, the phytochemical components of hot peppers respond differently to climatic factors—such as high rainfall, elevated air temperature, and intense sunlight—depending on the genotype’s ability to adapt to environmental changes.
This research aimed to explore the influence of climate factors, especially in the three weeks prior to harvest, on the reaction of key phytonutrients in industrial tomatoes used for juice thermal processing and their stability. The cultivation was performed in two areas with differing climatic conditions. In the region with higher temperatures and rainfall, the levels and stability of carotenoids were lower compared to the area characterized by warm temperatures and minimal rainfall during both the growth and harvest phases of the tomatoes. The extraction of cold-break (CBE) tomatoes from relatively cool and wet environments resulted in a loss of total carotenoids, particularly lycopene, amounting to 66% and 58% of the initial raw tomato content in 2018 and 2019, respectively, while a markedly reduced loss of 10% was observed after the CBE of tomatoes from the warmer and drier region in both years (36% and 35%). In contrast, hot-break extraction (HBE) demonstrated a higher stability of lycopene compared to CBE, with losses of 43% and 53% in 2018 and 2019, respectively. Additionally, the stability of lycopene in HBE did not show significant differences between the cultivation sites. Climatic conditions influenced the accumulation of geometrical isomers and oxidized forms of lycopene and β-carotene, especially in tomatoes grown in areas with higher rainfall and lower temperatures. A similar trend in response was noted for β-carotene, lutein, phytoene, and phytofluene, as well as total and individual tocopherols. Regarding vitamin C, the environmental factors had no meaningful impact on the vitamin content in tomato fruits; however, its stability during processing, especially with hot-break extraction, was considerably influenced by the climatic conditions of the cultivation site, with p values ranging from <0.01 to <0.001 across different products in various years. The content and stability of phytonutrients in pomace, the by-product from tomato juice processing, were also assessed. In conclusion, tomato fruits and processed products that boast high phytonutrient levels and stability during thermal processing can be achieved through cultivation in conditions of low rainfall and relatively high temperatures, particularly in the three weeks leading up to harvest.
Given the global importance of sweet potatoes as a nutrient-rich staple food, this research aimed to find the optimal cultivation practices to improve both yield and carotenoid content, with a particular focus on enhancing β-carotene content. In this study, the effects of different cultivation methods and plant densities on the agronomic parameters, physiological characteristics and carotenoid content of the ‘Beauregard’ variety were investigated across two consecutive growing seasons. Besides storage root yield, the key physiological parameters, including SPAD and chlorophyll fluorescence (Fv/Fm), were monitored to assess plant health and photosynthetic performance. Carotenoid content, including trans-β-carotene, cis-β-carotene, and ζ-carotene, was quantified using high-performance liquid chromatography (HPLC). Results indicated that the ridge cultivation method, particularly when combined with twin-row planting, consistently produced the highest yields, reaching the maximum of 40.87 t ha−1 in 2020. The flat cultivation method, especially in simple rows, showed the lowest yield. The analysis revealed that plant density had a more pronounced effect on yield and carotenoid content than the ridge or flat cultivation method alone. The maximum β-carotene content was achieved in the simple row (17,500 plants/ha) treatment planted on ridges with 247 µg/g. Significant correlations between both SPAD readings and Fv/Fm and yield were revealed, but no correlations with storage root carotenoid content were found. This suggests that, while these leaf physiological traits can be used to estimate the yield, they are not directly associated with the carotene content of the storage root. The study highlights the ridge cultivation and 35,000 plants/ha method as a stable and high-yielding option for ‘Beauregard’ in terms of improving and balancing the yield and carotenoid content; however, reducing the plant density resulted in elevated carotenoid content with significant yield reductions. The findings contribute to the understanding of how agronomic practices influence the nutritional and physiological traits of sweet potatoes, with implications for improving food security and nutritional outcomes in sweet potato cultivation.
Landraces are considered a crucial component of biodiversity conservation, serving as a reservoir of genetic diversity. Consequently, the collection, cultivation, and detailed characterization of such landraces constitute an inherent aspect of the world’s natural resource heritage. This effort holds promise for the development of elite varieties capable of thriving amidst continuous global climate fluctuations. In this context, we conducted a comprehensive assessment of the main agronomic attributes, physico-chemical properties, and functional quality traits of the major hot pepper landraces adapted to diverse climatic conditions in Tunisia. These landraces include ‘Dhirat’, ‘Semmane’, ‘Beldi’, ‘Nabeul’, ‘Jerid’, ‘Mahdia’, ‘Cayenne’, ‘Kairouan’, and ‘Baklouti’. Most of the pepper landraces exhibited satisfactory yields, ranging from 1163.25 to 1841.67 g plant−1 in ‘Jerid’ and ‘Kairouan’, respectively, indicating robust productivity, especially under prevailing climatic changes and high temperatures during both growing cycles. The levels of antioxidants comprising capsaicinoids, carotenoids, phenolics, and tocopherols, as well as radical scavenging activity, emerged as key discriminating factors among pungent pepper landraces. Irrespective of genotype, capsaicin and dihydrocapsaicin constituted the major capsaicinoids, accounting for 44–91% of the total capsaicinoids content. Total capsaicinoids ranged from 1.81 µg g−1 fw to 193.71 µg g−1 fw, with ‘Baklouti’ and ‘Jerid’ identified as the most pungent landraces. Total carotenoids ranged from 45.94 µg g−1 fw to 174.52 µg g−1 fw, with ‘Semmane’ and ‘Jerid’ exhibiting the highest levels. Considerable variation was observed in β-carotene content, spanning from 3% to 24% of the total carotenoids. α-Tocopherol content ranged from 19.03 µg g−1 fw in ‘Kairouan’ to 30.93 µg g−1 fw in ‘Beldi’, exerting a notable influence on the overall tocopherol content. Conversely, the β- and γ-tocopherol isomers were detected at very low concentrations. The total vitamin C content ranged from 132 mg 100g−1 fw in ‘Mahdia’ to 200 mg 100 g−1 fw in ‘Nabeul’, indicating relatively low genetic variability. However, large variability was detected in total phenolics content, ranging from 168.58 mg GAE kg−1 fw in ‘Beldi’ to 302.98 mg GAE kg−1 fw in ‘Cayenne’. Landraces such as ‘Dhirat’, ‘Nabeul’, ‘Semmane’, ‘Kairouan’, ‘Cayenne’, and ‘Mahdia’ appear suitable for both fresh consumption and processing, owing to their favorable average fruit weight, soluble solids content, and bioactive content. Among the pepper landraces tested, ‘Cayenne’ achieved the highest value of radical scavenging activity in both hydrophilic and lipophilic fractions (RSAHF and RSALF), with variations ranging from 59% to 120% for RSAHF and from 4% to 63% for RSALF. This study aims to preserve and enhance the value of local genetic resources and contribute to identify desirable traits for incorporation into breeding programs to develop high-quality, high-yielding landraces and elite lines.
For thousands of years, chili pepper has been used in cooking intensifying the aroma, colouring, and even flavouring with its pungency. Today ,it is also of interest for the various food and pharmaceutical industries due to its intrinsic characteristics. These characteristics of pepper and its yield can be affected by both the variety and the temperature fluctuation throughout the harvest period. The current work's objective was to investigate the effect of harvest time on vitamin C of different varieties of chili pepper C. frutescens and C. annuum cultivated in Hungary, as well as the yield of pepper in different harvesting periods. Vitamin C was determined by HPLC protocols. The differences between harvest times and varieties were analysed using Tukey post hoc test at 5%. All varieties showed fluctuation of vitamin C level, depending on the given harvest date. At the last harvest, all varieties had higher vitamin C content. All varieties had the same yield trend throughout the year but with different yields between each. Variety Hetényi Parázs had the highest vitamin C content and yield: 3720.53 µg g-1 vitamin C and 18.63 t ha-1 average yield, respectively.
Diclofenac, ibuprofen, and carbamazepine are three of the most widely detected and most concerning pharmaceutical residues in aquatic ecosystems. The aim of this study was to identify bacteria that may be involved in their degradation from a bacterial biofilm. Selective enrichment cultures in mineral salt solution containing pharmaceutical compounds as sole source of carbon and energy were set up, and population dynamics were monitored using shotgun metagenome sequencing. Bacterial genomes were reconstructed using genome-resolved metagenomics. Thirty bacterial isolates were obtained, identified at species level, and tested regarding pharmaceutical biodegradation at an initial concentration of 1.5 mg l(-1). The results indicated that most probably diclofenac biodegrading cultures consisted of members of genera Ferrovibrio, Hydrocarboniphaga, Zavarzinia, and Sphingopyxis, while in ibuprofen biodegradation Nocardioides and Starkeya, and in carbamazepine biodegradation Nocardioides, Pseudonocardia, and Sphingopyxis might be involved. During the enrichments, compared to the initial state the percentage relative abundance of these genera increased up to three orders of magnitude. Except Starkeya, the genomes of these bacteria were reconstructed and annotated. Metabolic analyses of the annotated genomes indicated that these bacteria harbored genes associated with pharmaceutical biodegradation. Stenotrophomonas humi DIC_5 and Rhizobium daejeonense IBU_18 isolates eliminated diclofenac and ibuprofen during the tests in the presence of either glucose (3 g l(-1)) or in R2A broth. Higher than 90% concentration reduction was observed in the case of both compounds.
Tomato landraces have progressively faded into obscurity, making way for new hybrids and elite tomato cultivars. This study presents a comprehensive evaluation of the agronomic attributes, physicochemical properties, and functional traits across seven cultivars, comprising two high-pigment varieties, ‘HLT−F81’ and ‘HLT−F82’, as well as five underutilized ancient-tomato genotypes considered as landraces. Most of the studied genotypes exhibited satisfactory horticultural and processing traits. The average fruit weight ranged from 73.3 g in ‘Rimone’ to 91.83 g in ‘HLT−F81’, while the soluble solids content ranged from 4.66 °Brix in ‘Justar’ to 6.08 °Brix in ‘HLT−F81’. The functional quality and the content of most antioxidants, as well as the antioxidant activity in both hydrophilic and lipophilic fractions, proved to be the most discriminating parameters among the tomato genotypes. The content of β−carotene and lycopene spanned from 2.94 mg kg−1 fw in ‘Rio Grande’ to 13.94 mg kg−1 fw in ‘HLT−F82’ and 227.8 mg kg−1 fw in ‘HLT−F81’, yielding large variations compared to ‘Rio Grande’. The total phenolic content ranged from 139.83 mg GAE kg−1 fw in ‘Rimone’ to 352.41 mg GAE kg−1 fw in ‘HLT-F81’, while the flavonoid content varied from 136.16 mg RE kg−1 fw in ‘Justar’ to 311.23 mg RE kg−1 fw in ‘HLT-F82’. The presence of tocopherol isomers was genotype-dependent, with a higher content in lines carrying the high-pigment mutations. Among the tested tomato genotypes, the high-pigment tomato line ‘HLT−F81’ achieved the highest hydrophilic and lipophilic antioxidant activity values. This study primarily focused on the recovery and valorization of tomato genetic resources and landraces. It also aimed to identify desirable horticultural (yield, low-input, and low-water demand), processing (°Brix and titratable acidity), and quality (rich antioxidant berries) traits for introgression into new tomato cultivars better suited to the evolving climate conditions of the near future.
Maintaining a diverse diet is essential for the preservation of one’s health and may contribute to the fight against significant civilization diseases such as obesity or diabetes. Sweet potato can be fitted into a diverse diet and serve as a functional food with its antioxidant content. Therefore, it is important to know how the production technology alters the content and composition of these antioxidant compounds. The objective of this study was to collect information on how the increased potassium dominant fertilizer levels and also the additional high-dose fertigation can affect the phytonutrient contents and yields in an orange- and a purple-fleshed sweet potato cultivar. Field experiments were conducted in the Hungarian county of Heves in two consecutive growing seasons in 2021–2022. Different doses of potassium-predominant fertilizer were applied to an orange flesh (Beauregard) and a purple flesh (Stokes Purple) varieties of sweet potatoes. Different application techniques were used in the form of base and top dressing at different rates. The effect on yield and polyphenol content of the different fertilizer rates was investigated. Analytical studies were carried out by high-performance liquid chromatography (HPLC). In the case of the Beauregard variety, in addition to identifying the carotenoids, we also performed their quantitative determination. We found that 87% of the carotenoid content was ß-carotene. The total anthocyanin content was investigated for the purple variety—Stokes Purple, for which a new extraction method was developed. In our study, the split dosages, when the pre-planting fertilizer was supplemented with additional liquid fertilization, resulted in 36 and 30.5% higher yields in the Beauregard in Experiment I and Experiment II, respectively, compared to the untreated control plots over the two years. The additional liquid fertilizer increased the yield to a lesser extent when compared to treatments received only pre-planting fertilizer. As for Experiment III, the split dosages resulted in 34.4% higher yields in the Stokes Purple compared to the control plots. However, the additional liquid fertilizer was not effective at all when the plants received a double dose of pre-planting fertilizer in the case of Stokes Purple. Total carotenoid (Experiment I–II) was higher and anthocyanin yield per plant (Experiment III) was significantly higher in the split-dosage treatment than in the untreated control plots.
Growing conditions and seasonal fluctuations are critical factors affecting fruit and vegetable nutritional quality. The effects of two partially overlapping cropping seasons, early (ECS; January–May) and full (FCS; March–July), on the main carpometric traits and bioactive components of different watermelon fruits were investigated in the open field. Four watermelon genotypes, comprising of three commercial cultivars ‘Crimson Sweet’, ‘Dumara’, ‘Giza’, and the novel hybrid ‘P503 F1’, were compared. The carpometric traits varied significantly between genotypes. Soluble solids and yield were higher under FCS than ECS. The variation affecting colour indexes between the two growing seasons exhibited a genotype-dependent trend. The antioxidant components and radical scavenging activity of watermelon fruits were also significantly affected by differences in received solar energy and temperature fluctuations during the trial period. The average citrulline, total phenolics and flavonoid contents were 93%, 71% and 40% higher in FCS than in ECS. A genotype-dependent variation trend was also observed for lycopene and total vitamin C between cropping seasons. The hydrophilic and lipophilic radical scavenging activities of the pulp of ripe watermelon fruits of the different genotypes investigated varied between 243.16 and 425.31 µmol Trolox Equivalent (TE) of 100 g−1 of fresh weight (fw) and from 232.71 to 341.67 µmol TE of 100 g−1 fw in FCS and ECS, respectively. Our results, although preliminary, show that the functional quality of watermelon fruits is drastically altered depending on the environmental conditions that characterize the ECS and LCS.
Artichoke (Cynara scolymus L.) is a worldwide popular horticultural crop. Interest in assessing bioactive compounds with potential health benefits in artichoke is increasing. Therefore, in this study, the variability in total phenolic and flavonoid contents of six artichoke cultivars, including five purple namely Brindisie, Opal, Conserto, Romanesco and Rouge de France as well as an ordinary white artichoke variety were investigated. The results showed significant differences in total phenolic and flavonoid contents between artichoke cultivars. Total phenolic content ranged from 17.31 mg GAE/ g DW in the white artichoke variety to 21.31 mg GAE/g DW in Romanesco. Flavonoid content ranged from 4.51 mg RE/g DW in white artichoke to 7.06 mg RE/g DW in Rouge de France. Therefore, the highest total phenolic content was shown by Romanesco. However, the highest flavonoid content was recorded for both Opal and Rouge de France. This study demonstrates the importance of genotypic variability in shaping the levels of total phenolic and flavonoid, emphasizing the need to evaluate artichoke biodiversity in order to improve its nutritional value and to contribute towards increasing the intake of antioxidants.
In the fields of human nutrition and the food industry, the various products of the spice red chili pepper have sparked increased attention. The purpose of this study was to determine the quantity and stability of carotenoids, carotenoid esters, tocopherols, and capsaicinoids in new spice chili hybrids under traditional drying utilizing cutting-edge analytical techniques. In both fresh and conventionally dried goods, the quantities and stability of bioactive components vary significantly between the hybrids. The highly pungent cultivar Unijol, which dispersed capsaicinoids 7-9 times more than the other cultivars, had the highest retention of carotenoids (76-138) upon drying. The levels of carotenoids discovered in naturally dried samples were larger in all cultivars than those found in raw materials, indicating continuous over-ripeness processes during long-term drying. Tocopheml stability was ranked Unijol > Hetenyi > Unikal, with retention rates of 82-93, 72-79, and 63-73 percent, respectively. The genotypes differed not only in capsaicinoids content, but also in the ratio of capsanthin to dihydrocapsanthin, as well as in their stability during natural and thermal drying, with Unijol being the most stable and Hetenyi being the least, with maximal retention of 71-92 percent and 58-86 percent, respectively.
In light of the great technological progress in non-destructive quality detection methods, sweetness is no longer the essential parameter in evaluating watermelon quality. There is an aspiration to determine physicochemical quality characteristics to enable us to select the best cultivars, agricultural practices, and harvest dates. In the present work, three different watermelon cultivars (Lady, Galander, and Style) were harvested at three consecutive harvest times. Two pieces were taken from each watermelon sample, one from the middle (part A) and the other from the ends (part B), to track the intensity of quality parameters inside the watermelon. Parts A and B were subjected to Vis/NIR spectroradiometer (475:1075 nm), near-infrared spectroscopy (NIRS) (950:1650 nm), and high-performance liquid chromatography to assess the physicochemical quality. Calibration and prediction models were conducted using partial least squares regressions (PLS). The results indicated that the harvesting time significantly influenced the color and chemical parameters. Quality parameters concentrations markedly degraded towards late harvest. The highest concentrations of quality parameters were sighted for the middle zone (part A), especially in the Galander cultivar. Spectroradiometer achieved the best coefficient of prediction (R2P) ≃ 0.88 and 0.81 attached with the lowest value of the standard error of prediction (SEP) ≃ 0.03 and 1.06 for chroma (C*) and yellowness index (YI). However, the findings showed the superiority of the NIRS compared to the Vis-NIR method. The highest R2P was achieved by values 0.92, 0.91, 0.90, 0.89, 0.85, and 0.85 for lycopene, total carotenoids, vitamin C, β-carotene, γ-content, and TSS, respectively. It could be concluded that the NIRS has the ability to monitor the maturity development and determine the harvest dates practically and reliably.
The aim of the present work was to evaluate the influence of genetic impact on the content of some characteristic secondary metabolites in tomato fruits. The study was conducted to screen 14 different tomato genotypes for antioxidant capacity and quality attributes (polyphenols, tocopherols, carotenoids, vitamin C) to select the genetic lines with high biological value, multiple disease resistance, and high yield capacity for further usage in crop improvement programs. Significant differences were found among the different hybrids and cultivation seasons for the phytochemical content of the fruits. The varieties developed by breeding to increase their resistance were found to differ significantly. During a 3-year cultivation experiment, the level of lycopene in freshly harvested fruits ranged between 10.38 and 63.23 mg.kg−1 fwt for outdoor-cultivated Naik114 and Naik352, respectively. As for β-carotene, its content varied between 0.49 mg.kg−1 for Unorosso and 11.66 mg.kg−1 for Cherrola F1. The highest level of vitamin C (702.59 mg.kg−1) was recorded for Cherrola F1, while the lowest level (1.36.86 mg.kg−1) was determined in fruits of Unorosso. Neither polyphenol nor vitamin C showed positive correlation with antioxidant activity. In the three cultivation seasons, the highest concentration of polyphenols (579.19–804.12 mg.kg−1 fwt) was determined in fruits of outdoor-cultivated Cherolla F1 variety. The α- and γ-tocopherol content varied between 2.56 and 18.99 mg.kg−1, and 0.28 and 9.35 mg.kg−1, respectively, in fresh tomato fruit. Among the newly bred resistant varieties, the ZKI114 variety was proved to have outstanding features concerning the amounts of the bioactive components.
An efficient and rapid liquid chromatographic method was developed for the separation of carotenoids and their geometrical isomers in tomato products using a core C30 column of 2.6 μm particles with gradient elution of tert-butyl-methyl-ether in 2% water in methanol. Excellent separation of the major carotenoids such as lycopene, β-carotene and lutein as well as their geometrical isomers and oxygen-containing derivatives with resolution factors ranging between 0.78 and 4.0 and selectivity of 1.01-1.63 was achieved. Validation of the developed method met the acceptance criteria concerning linearity, recovery, precision and limit of detection and quantification. Calibrations were linear with correlation coefficient (R2) values between 0.9966 and 0.9999. The limit of detection and quantification values were found to be 0.008 and 0.017 and 0.029 and 0.056 μg/mL, respectively. Recovery of 94.3-99.9%, intraday precision of 1.81-4.45% and interday precision of 3.13-6.86% were obtained. The hyphenation of liquid chromatography with diode-array and mass spectrometry was helpful in the identification of the separated carotenoids particularly the unusual di-hydroxy cyclolycopene adduct and di-methoxy lycopene determined for the first time in tomato products. Commercially available kinds of tomato juice and ketchup were evaluated based on their carotenoid content.
The results showed that soil electrical conductivity, (EC2: 7 dS/m) increased soluble solids, lycopene content, total phenolic content, hydrophilic and lipophilic radical scavenging activities (HRSA and LRSA) by 14.2, 149, 20, 46.4, and 19.0%, respectively, compared with control. Under 0.5% spent engine oil (SEO), flavonoid content decreased by 21.7% compared with the control. HRSA and LRSA of fruits subjected to EC2/SEO1 treatment were, respectively, 45.9 and 35.5% lower than control. The a*/b* ratio was positively and significantly (P < 0.01) correlated with β-carotene (R = 0.78), lycopene (R = 0.68), total vitamin C (R = 0.71), α-tocopherol (R = 0.83), γ-tocopherol (R = 0.66), HRSA (R = 0.93), LRSA (R = 0.80), and soluble solids (R = 0.84) suggesting that it may be a promising indicator of fruit quality in areas affected by such constraints. The research revealed that combined stresses induce responses markedly different from those of individual treatments, which strain the need to focus on how the interaction between stresses may affect the functional quality of tomato fruits.