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Carotenoid and antioxidant content of ground paprika from indoor-cultivated traditional varieties and new hybrids of spice red peppers
Abstract
The content of carotenoids and the main antioxidant vitamins in traditional varieties and new hybrids of spice red pepper (Ccapsicum annuum L.) cultivated under plastic houseindoor conditions was studied. The varieties and hybrids were evaluated on the basis of results obtained from liquid chromatographic determination of carotenoid and antioxidant vitamins, and compared for their response to different drying conditions. Ground paprika from all varieties and hybrids cultivated under plastic houseindoor conditions were remarkably rich in colorants (average: 8629 μg/g d) and vitamin E (average: 1189 μg/g), but vitamin C level was found to be higher (average: 8.3 mg/g DWdm) in paprika from arable-landoutdoor cultivated peppers dried naturally. The paprika from the Spanish hybrids ‘Jeromin’, ‘Jaranda’, 1970/05 and the varieties Hungarian ‘Remény’ and ‘SZ-80’ varieties as well as the hybrid ‘1970/05’ contained the highest level of carotenoids and antioxidants (P < 0.05). The different varieties and hybrids differed in their response, in terms of stability, to drying conditions. Natural drying was favourable for the highest carotenoid retention, but not for the retention of vitamin C. It was surprising that drying at 50 °C for 24 h resulted in a paprika with vitamin C content 1.5–3 times higher than that found in paprikas produced with other drying methods.
... Urfa isot peppers are approximately 3-5 on the 1-10 heat scale, and the heat comes out slowly. Red bell peppers, which are the raw materials of the ground red peppers, are an excellent source of bioactive compounds including provitamin A, vitamins B, C, and E, as well as phytochemicals, such as phenolic compounds, carotenoids and capsaicin with well-known favorable health eff ects, including antioxidant, anticarcinogenic, antimutagenic, antiaging, and antibacterial properties (10,14). With their health-enhancing eff ects, bioactive compounds from red bell peppers are the ones that health benefi ts (clear the lungs and sinuses, protect the stomach by enhancing the flow of digestive juices and protect the body against cancer through antioxidant activity) were associated (18). ...
... Red peppers are naturally rich in ascorbic acid, which has an important vitamin-possessing, highly oxygenquenching and free radical-scavenging activity and which acts as a protector of pigments preserving them from oxidation (10). The sample of homemade red-blackish ground pepper contained the highest quantities of ascorbic acid, followed by factory-made red-purplish ground pepper (Tab. ...
... The highest lycopene and β-carotene levels were determined in homemade red ground pepper, followed by factory-made red ground pepper. Since it is subjected to naturally drying conditions, which are less drastic than the thermal drying applied in factories, homemade red ground pepper contained the high-est content of β-carotene and lycopene (10). Although homemade red-blackish ground pepper is subjected to natural drying, too, it had the lowest lycopene and β-carotene contents. ...
Urfa isot pepper is one of the most important spices in the diet of Turkish people, particularly of those in the Sanliurfa region. This is the first study reporting the bioactive compounds (p-carotene, lycopene, ascorbic acid, phenolic compounds, capsaicin) and antioxidant activity of ground Urfa isot peppers produced both at homestads and factories. Factory-made red-blackish isot pepper showed the highest DPPH radical-scavenging activity, followed by homemade red-blackish isot pepper and homemade red isot pepper. FRAP values of all Urfa isot peppers were statistically in the same group. Homemade red isot pepper had the highest total phenolic content, lycopene and p-carotene. The capsaicin content of ground Urfa isot peppers varied from 0.15-1.2 mg/g of pepper. The homemade red-blackish ground pepper had the highest ascorbic acid level. Phenolics of peppers were remarkable and higher than those reported in the literature. With their high number of phenolic constituents, as well as other bioactive compounds, ground Urfa isot peppers can be considered an important nutri-tional and functional food resource.
... O processo de fritura obtém os maiores valores médios de ASTA (72,214) de carotenóides totais (95,464), L* (38, 26), a* (34, 13). A Secretaria mantém os mais altos atributos de cor b* (21,81), h° (30,42), IP (145,40), ΔE* (4,84). Estes resultados mostram que a fritura é uma operação que melhora o atributo de cor, através do aumento da disponibilidade de carotenóides e aumentar a* cor da superfície. ...
... A nivel industrial, la coloración roja del pimentón y el contenido de oleorresina son criterios de calidad fundamentales que determinan y expresan el contenido total de carotenoides presentes en el fruto. El valor comercial del pimentón depende básicamente de estos dos factores, por lo que la cuantificación del contenido de pigmentos carotenoides es de gran interés [3,4]. los principales compuestos responsables del color en este material vegetal, obedecen a compuestos carotenoides entre los que se destacan la capsantina, neoxantina, violaxantina, zeaxantina, luteína, β-criptoxantina y el β-caroteno [5]. ...
El color es uno de los parámetros más importantes a la hora de medir la calidad de productos que van a ser procesados a partir del pimentón rojo (Capsicum annuum), para la fabricación de condimentos, colorantes, conservas y aderezos. En este estudio, se evaluó el efecto del procesamiento térmico (freído y conserva) con respecto al cambio de color y los carotenoides en frutos de pimentón rojo. Para el freído se utilizó aceite de soya a una temperatura de 175°C por 5 min; en la elaboración de la conserva, se realizó un proceso de escaldado y pasteurización a 100°C durante 15 min. Después de los tratamientos térmicos (freído y conserva) la concentración de carotenoides totales y el color superficial en los frutos de pimentón rojo se afectaron significativamente. El proceso de freído obtiene los valores medios más altos de unidades ASTA (72,214), Carotenoides Totales (95,464), L* (38,26) y a* (34,13). La conserva registró los atributos más altos de color b* (21,81), h° (30,42), IP (145,40) y ΔE* (4,56-31,84). Estos resultados evidencian que el freído es una operación que mejora el atributo de color, al aumentar la disponibilidad de carotenoides e incrementar el color superficial a*.
... Samples have been filtrated through a 0.45 µm diameter PTFE HPLC filter, before injection on the column. Carotenoids were separated on a Purospher ® STAR RP C18 end-capped 3 µm, 250 × 4.6 mm column with 50 minute long gradient elution according to the method of Daood et al. (2014) [27]. Peaks were identified by comparing their retention time and maximum absorbance to standards (Sigma Aldrich, Budapest). ...
... Samples have been filtrated through a 0.45 µm diameter PTFE HPLC filter, before injection on the column. Carotenoids were separated on a Purospher ® STAR RP C18 end-capped 3 µm, 250 × 4.6 mm column with 50 minute long gradient elution according to the method of Daood et al. (2014) [27]. Peaks were identified by comparing their retention time and maximum absorbance to standards (Sigma Aldrich, Budapest). ...
Grafting by vegetables is a practice with many benefits, but also with some unknown influences on the chemical composition of the fruits. Our goal was to assess the effects of grafting and storage on the extracted juice of four orange-fleshed Cantaloupe type (Celestial, Donatello, Centro, Jannet) melons and two green-fleshed Galia types (Aikido, London), using sensory profile analysis and analytical instruments: An electronic tongue (E-tongue) and near-infrared spectroscopy (NIRS). Both instruments are known for rapid qualitative and quantitative food analysis. Linear discriminant analysis (LDA) was used to classify melons according to their varieties and storage conditions. Partial least square regression (PLSR) was used to predict sensory and standard analytical parameters. Celestial variety had the highest intensity for sensory attributes in Cantaloupe variety. Both green and orange-fleshed melons were discriminated and predicted in LDA with high accuracies (100%) using the E-tongue and NIRS. Galia and Cantaloupe inter-varietal classification with the E-tongue was 89.9% and 82.33%, respectively. NIRS inter-varietal classification was 100% with Celestial variety being the most discriminated as with the sensory results. Both instruments, classified different storage conditions of melons (grafted and self-rooted) with high accuracies. PLSR showed high accuracy for some standard analytical parameters, where significant differences were found comparing different varieties in ANOVA.
... The red, orange, or yellow color of the mature chile fruit is the result of the accumulation of cultivar-or variety-specific mixtures of carotenoids in the pericarp. In red fruit, capsanthin is the most abundant carotenoid and this carotenoid generates the red color in the fruit (Daood et al., 2014; Deli et al., 2001). b-carotene and b-cryptoxanthin are orange-colored carotenoids that are essential provitamin A nutrients. ...
Additional index words. carotenes, provitamin A, fruit quality Abstract. Two key fruit qualities in Capsicum annuum are fruit pungency and color. We characterize 13 New Mexican landraces for fruit quality traits at both the chemical level measuring the capsaicinoids, dihydrocapsaicin, and capsaicin as well as five carotenoids, b-carotene, b-cryptoxanthin, zeaxanthin, violaxanthin, and capsanthin, and at the genetic level sequencing two genes in these landraces, Kas I, a capsaicinoid pathway gene, and Ccs, a carotenoid pathway gene. All of the landraces had unusually high levels of dihydrocapsaicin in comparison with capsaicin levels. The levels of the most abundant red pigment, capsanthin, ranged between 468 and 1007 mg · g L1 dry weight fruit in field-grown fruit, whereas levels of b-carotene were more similar in the landraces (13 to 22 mg · g L1 dry weight fruit). Twelve different Kas I alleles were found in the landraces, which predicted six novel KAS proteins in these landraces. Seven alleles of Ccs were found, which predicted three novel CCS proteins. These results demonstrate that the landraces under cultivation in small farms and pueblos in northern New Mexico are sources of important genetic diversity for Capsicum crops.
... The red pigments are accompanied by other xanthophylls and carotenes such as zeaxanthin, β-cryptoxanthin, violaxanthin, antheraxanthin and β-carotene. The carotenoid pattern and the pigment concentrations vary widely depending on cultivars and ripening stage (Deli et al., 2001;Daood et al., 2014; Gómez-Garcia and Ochoa-Alejo, 2013) ...
Carotenoids of chili peppers are important components of their antioxidant profiles. Analytical quantification of carotenoid components is time and labour consuming. That is why researchers try to develop non-destructive and rapid methods to assess the quality parameters. The present study reports the suitability of a portable handheld visible near infrared (VIS/NIR) spectrometer to predict yellow and red carotenoid components of chili peppers. Spectral ranges of 325-1075 nm were directly acquired on fresh fruits in three ripening stages of three different chili varieties using a FieldSpec HandHeld 2™ Portable Spectroradiometer. Immediately after spectral measurement, each fruit sample was analysed to determine total red and yellow carotenoid components in fresh weight. Partial least square regressions (PLSR) were carried out to perform models of prediction between spectral data and the values obtained from the analytical results. The accuracy of the predictions was discussed according to the coefficient of determination value (R 2), the root mean square error of calibration/cross-validation (RMSEC/CV). Such analyses resulted in calibration equations with R 2 =0.88 and 0.63; root mean square error of calibration were 11.4, 17.6; and RMSEC/CV results were 17.1 (yellow) and 21.4 mg/100g (red) respectively.
... The lowest levels were recorded for the highly pungent Unijol cultivar. The vitamin E level assessed for the new hybrids ranged between 392 and 448 μg g -1 dm, which is well below the 990 μg g -1 dm determined in pungent spice pepper (Daood et al., 2014) and slightly lower than the 621 μg g -1 determined in a lyophilized matter of Capel hot cultivar of Capsicum annuum (Perucka & Materska, 2007). ...
Spice peppers have valuable phytonutrients that make them of special interest from nutritional and pharmaceutical points of view. This work was conducted to study the impact of γ-irradiation before over-ripening on phytonutrients of new hybrids of chili peppers. The investigated cultivars were found to significantly differ in their content of capsaicinoids (P<0.01) and carotenoids (P<0.05) with Unijol being the richest in pungency and the poorest in the total carotenoid content although its content of bioactive zeaxanthin and β-carotene was the highest. The 3096 μg g-1 fresh weight, which equals 22114 μg g-1 dry weight, and 331710 Scoville Heat Unit (SHU) were recorded for Unijol. The examined cultivars differed significantly in the response of phytonutrients to γ-irradiation treatments. The dose of 2.5 kGy promoted the biosynthesis and stability of capsaicinoids and carotenoids, while the highest dose of 10 kGy decreased, to some extent, the content of phytonutrients except tocopherols. The magnitude of promotion and degradation caused by irradiation was found to be cultivar- and dose-dependent. The highest losses in the total capsaicinoid, total yellow xanthophyll, total red xanthophyll, and total carotenoid content of 19, 34, 37, and 38% respectively were recorded for Unijol as a result of γ-irradiation at 10 kGy.
... Inbaraj et al. (2008) extracted zeaxanthin and β-cryptoxanthin esters from Goji (Lycium barbarum) with a mixture of hexane: ethanol:acetone:toluene (10:6:7:7, v/v/v/v). N,N-dimethyl formamide was used for xanthophyll esters extraction from potato (Fernandez-Orozco et al., 2013) and a mixture of 1,2-dichloroethane:acetone:methanol (2:1:1, v/v/v) for carotenoid esters extraction from Capsicum annum L. species (Daood et al., 2014). Almost all the procedures used the addition of NaHCO3, MgCO3 or CaCO3 in the first steps of the extraction in order to neutralize the acidity of plant tissues and to prevent rearrangements. ...
Carotenoids possessing hydroxyl groups (xanthophylls) are often found as fatty acid esters in many fruits and vegetables. The developments in high resolution chromatographic and spectroscopic techniques have led to a detailed characterization of xanthophyll esters in commonly consumed fruits and vegetables, such as apples, apricots, mandarins, mangoes, papayas, red and chili peppers, potatoes or squash. Some more rich sources have been identified, like wolfberry (goji), sea buckthorn, persimmon, whose popularity is increasing due to the high content of bioactive compounds. Esterification increases the lipophilicity of xanthophylls and contributes to the sequestration of carotenoids, to the formation of specialized structures in the chromoplasts and to an increased photoprotection. The process occurs during ripening in fruits and it is associated with a significant change in colour. Even if the specific enzymes which catalyze the esterification process were not characterized yet in fruits, detailed analytical data regarding the carotenoid composition suggested a selectivity of these enzymes for certain fatty acids and selectivity for the ring in the case of non-symmetric xantophylls. Xanthophyll esters seem to be efficiently hydrolyzed and absorbed in humans leading to a comparable bioavailability to the unesterified compounds. In addition, the xanthophyll esters preserve the antioxidant capacity of the parent compounds while having a better stability in fruits during storage and processing. All these properties are important from the perspective of the use of fruits rich in xanthophyll esters as valuable components of the human diet and as sources of bioactive compounds in the prevention of severe degenerative diseases.
... Electrochemical techniques have also been used to characterize capsaicinoids (Manaia et al. 2012;Randviir et al. 2013). Ethyl acetate (Viñas, Campillo, and Hernández Córdoba 1992) and hexane (Gnayfeed et al. 2001) have been employed to extract tocopherols, generally with fluorescence detection (Daood et al. 1996;Ramesh et al. 2001;Daood et al. 2014). ...
Spanish paprika was clustered on the basis of the Spanish Protected Designation of Origin “Pimentón de La Vera” by molecular absorbance and fluorescence with principal component analysis and parallel factor analysis. Rapid extraction of carotenoids, capsaicinoids, and tocopherols was optimized; the best conditions included ethanol as the extractant, an extraction time of 10 min in an ultrasonic bath, and a sample size of 0.1 g. The procedure provided good precision with a relative standard deviation of 1.2% for four samples. Molecular absorption spectra were obtained from 250 to 600 nm and fluorescence excitation and emission spectra were collected from 200 to 295 nm and 300 to 400 nm, respectively. Forty-eight “Pimentón de La Vera” paprika samples and nineteen samples from other origins were characterized. A principal component analysis model was constructed from the absorption spectra and clustering was obtained based on the origin. Parallel factor analysis was performed on the fluorescence data and better characterization of the origin was obtained.
... The red, orange, or yellow color of the mature chile fruit is the result of the accumulation of cultivar-or variety-specific mixtures of carotenoids in the pericarp. In red fruit, capsanthin is the most abundant carotenoid and this carotenoid generates the red color in the fruit (Daood et al., 2014;Deli et al., 2001). b-carotene and b-cryptoxanthin are orange-colored carotenoids that are essential provitamin A nutrients. ...
Two key fruit qualities in Capsicum annuum are fruit pungency and color. We characterize 13 New Mexican landraces for fruit quality traits at both the chemical level measuring the capsaicinoids, dihydrocapsaicin, and capsaicin as well as five carotenoids, β-carotene, β-cryptoxanthin, zeaxanthin, violaxanthin, and capsanthin, and at the genetic level sequencing two genes in these landraces, Kas I, a capsaicinoid pathway gene, and Ccs, a carotenoid pathway gene. All of the landraces had unusually high levels of dihydrocapsaicin in comparison with capsaicin levels. The levels of the most abundant red pigment, capsanthin, ranged between 468 and 1007 μg·g-1 dry weight fruit in field-grown fruit, whereas levels of β-carotene were more similar in the landraces (13 to 22 μg·g-1 dry weight fruit). Twelve different Kas I alleles were found in the landraces, which predicted six novel KAS proteins in these landraces. Seven alleles of Ccs were found, which predicted three novel CCS proteins. These results demonstrate that the landraces under cultivation in small farms and pueblos in northern New Mexico are sources of important genetic diversity for Capsicum crops. © 2014 American Society for Horticultural Science. All rights reserved.
... mg aralığında kaydedilmiştir [27]. Doğal yollarla kurutulmuş kırmızı biberler, 862.9 mg β-karoten/100 g KM içeriğine sahip olduğu tespit edilmiştir [17]. Capsicum annuum L. cinsi kırmızı biberin 4 olgunluk döneminde içeriğindeki değişimin incelendiği bir çalışmada; kırmızı renge dönüşen olgun biberin β-karoten içeriği, ham dönemde yeşil biberdeki β-karoten içeriğinden yaklaşık olarak 4 kat fazla bulunmuştur [34]. ...
... ascorbic acid was detected in sun-dried paprika that contained significantly lower level of α-Tocopherol content than that found in the pericarp of thermally dried Sz20 paprika and slightly higher than that found in Sz20 + seed. This agrees with an earlier study by Daood et al. (1996Daood et al. ( , 2014, in which the retention of ascorbic acid and tocopherol has been found to be significantly lower in naturally dried paprika than in forced air-or thermally dried paprika. The enzymatic degradation of ascorbic acid during the relatively long period of natural drying is more effective than the degradation caused by a short-time thermal drying. ...
This study investigated the impact of rosemary extract on the endogenous antioxidants and color characteristics of spice paprika powders with regard to origin and processing method. The shorter over ripening period and industrial drying was advantageous for the retention of phytochemicals, in contrast with sun drying. Rosemary extract supplementation up to 0.25% reduced the color loss from 23%–36% to 14%–27% after a 12‐month storage period. The surface color (L*, , ) of milled paprika was strongly influenced by the origin and the processing method applied to dehydrate paprika pods. The color difference parameters showed that the perceptibility of color change did not occur during more than 9 months with 0.25% rosemary extract. The extract competed actively with α‐tocopherol in the anti‐oxidation process in the presence of oil from paprika seeds. The low level of ascorbic acid gave the chance for the antioxidants from rosemary to dominate and prevent the whole system.
Practical application
Spice paprika powder is a color‐improving ingredient in several dehydrated foods, in which improved color retention is a reasonable expressed or latent demand. The study demonstrated that the shorter over ripening period and industrial drying is advantageous for the retention of phytochemicals. The antioxidant supplementation improves the color retention of paprika powder products and compensates the adverse effects of post‐harvest factors. Therefore, the loss of quality and commercial value can be moderated. The rosemary extract contributes to the reduction of color loss more effectively in the presence of paprika seeds as a source of higher oil content. Besides the extractable color stabilization, the perceptibility of color change can be avoided for several months. This is an important result from the point of view of consumer opinion, as generally the visual color of spice paprika products is associated with the quality and coloring power.
... Paprika powder is used to improve the sensory properties of foods, as well as for medicinal purposes (Nieman et al. 2012). Paprika retains a high content of compounds with antioxidant activity (e.g., vitamin A, C and carotenoids) after drying and grinding (Daood et al. 2014). Because of these this, dried paprika powder has gained a great interest and demand throughout the world. ...
Dried red pepper is one of the most commonly used spices in many parts of the world. In this study molecular biology methods were applied for detection of contamination in nine samples of paprika powder. Internal Transcribed Spacer (ITS) regions were selected for sequencing as they have a high variability between species and organisms and therefore are an appropriate tool for taxonomic identification. The sequence analysis of the ITS regions were identified by high sequence similarity with the ITS regions of many microscopic fungi, especially representatives of the class Ascomycota and several other yeast species. This work was a qualitative rather than a quantitative detection, so the extent to which fungi and yeasts were present in the samples is unknown. However, supplied quality certificates (microbiological data) indicated the overall quality of samples. Harmful microorganisms were identified in the paprika powder samples and the likely mode of contamination was identified. Practical Application: The presence of undesirable pathogens can be a serious problem for consumers, especially contamination by microscopic fungi that have the potential to produce mycotoxins. Today's conventional methods for determining contamination by microorganisms are time consuming and can be difficult to identify some less common types of pathogens. Fungal DNA (ITS regions) sequences of the class Ascomycetes were identified from samples of sweet and hot paprika powder.
... Pungency is often expressed in Scoville Heat Units (SHUs) [17]. The interest in carotenoids from a nutritional standpoint has greatly increased recently because of their purported health benefits [18][19][20] including the ability to act as a provitamin A. Flavonoids are bioactive compounds found in plants. Previous studies indicated that consumption of food containing these compounds may reduce the incidence of cancer and cardiovascular diseases [21,22]. ...
Hot water or super-heated steam blanching of dried paprika changes its quality characteristics (L-ascorbic acid level, total polyphenol content, and color), which are in turn influenced by the peroxidase (POD) activity residual ratio. In this study, the optimum blanching conditions for production of high-quality dried paprika was determined by simultaneous evaluation of several quality characteristics based on conjoint analysis. This analysis also took into consideration the individual preferences of consumers. Residual ratio of L-ascorbic acid to total polyphenol in dried samples was the highest at a POD activity residual ratio of 0.8. Minimum color change of the dried samples was observed at a POD activity residual ratio of 0.1. Taken together, these results, as well as the individual preferences of consumers, suggest that optimum blanching conditions for the production of high-quality dried paprika were attained at a POD activity residual ratio of 0.8.
The storage-stability of extractable colour in paprika powder is strongly influenced by the processing steps. The purpose of this research work was to decrease the degradation rate of extractable colour of paprika powders to 3-4 ASTA units/month and increase the shelf-life. Fractional factorial experimental design and desirability function-based approach was applied to moderate the adverse effect of the key-importance processing steps on colour agent content. Photochemical-accelerated shelf-life test was used for the empirically-based quality improvement. Post-harvest ripening, drying, sorting (seed content), milling and additives (paprika seed oil, tocopherol extract) were identified as important for the degradation rate of extractable colour. The colour stability was very sensitive to the milling and drying intensity, while proper setup of other processing steps compensated the adverse effect of drying and milling parameters. The supplementation with cold-pressed spice paprika seed oil was demonstrated as a natural way of colour stabilization. At the highest desirability value (0.986) the rate constant of accelerated colour stability test (k) and shelf-life time (θS[100ASTA]) were −0.494 ASTA units/day and 2326 days, respectively. Alternative factor level settings enabled taking into account processing-tradition and efficiency expectation. In these cases, desirability values and the predicted shelf-life were 0.5-0.8 and 712-918 days, respectively. Validation study showed that the real observed rate constant and shelf-life values met the predicted values and their 95% confidence interval.
This chapter provides an overview of production, varieties, postharvest handling and storage, utilization, quality characteristics, processing, and food safety issues of Capsicum peppers. Global production of Capsicum peppers mainly comprises: the mild to highly pungent chili peppers; bell and sweet peppers utilized as vegetables; and paprika, primarily traded as a spice. The world production of fresh and dry chilies and green bell peppers in 2014 was 32.32 and 3.82 million metric tons (MMT), respectively. China was the leading producer of green types with 16.12 MMT, followed by Mexico, Turkey, Indonesia, and Spain. Postharvest handling and storage practices have a major impact on the quality and shelf-life of peppers. The postharvest storage quality and shelf-life depends on the types of storage regime involved—for example, normal refrigerated and controlled atmosphere (CA) storage, modified atmosphere packaging (MAP), and a variety of postharvest treatments.
Dried and ground red pepper is a spice used as seasoning in various traditional dishes all over the world; nevertheless, the pedoclimatic conditions of the diverse cultivation areas provide different chemical characteristics, and, consequently, diverse organoleptic properties to this product. In the present study, the volatile profiles of 96 samples of two different ground bell peppers harvested in diverse Italian geographical areas, Altino (Abruzzo) and Senise (Lucania), and a commercial sweet paprika, have been studied by means of headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). The investigation of their volatile profile has led to the identification of 59 analytes. Eventually, a discriminant classifier, Partial Least Squares Discriminant Analysis (PLS-DA), was exploited to discriminate samples according to their geographical origin. The model provided very accurate results in external validation; in fact, it correctly classified all the 30 test samples, achieving 100% correct classification (on the validation set). Furthermore, in order to understand which volatiles contribute the most at differentiating the bell peppers from the different origins, a variable selection approach, Variable Importance in Projection (VIP), was used. This strategy led to the selection of sixteen diverse compounds which characterize the different bell pepper spices.
Background
To this day, many species of peppers, genus Capsicum, have been identified and are the subject of several researches. However, only 5 are commonly used: C. annuum; C. baccatum; C. chinense; C. frutescens and C. pubescens. When associated with a healthy diet, the frequent intake of peppers has been positively correlated to improvements in human health. Most effects are due to the presence of a wide range of bioactive compounds, responsible for their functional properties as well as their technological potential as a food additive. Among the bioactive compounds present in these fruits are capsaicinoids, phenolic compounds, carotenoids, vitamins C and E.
Scope and approach
The goal of this review is to summarize the main findings regarding the bioactive compounds found in peppers and their technological and functional applications.
Key Findings and Conclusions: Results show that despite all health claims and technological potential reported, not all species were thoroughly studied and their potential is still unclear.
Chilli pepper is a widely spread vegetable crop and one of the main spices used all over the world. Its properties comprise high antioxidant capacity and content of several healthy-related compounds including vitamin C, carotenoids and capsaicinoids. In countries of the Mediterranean basin, chilli production is largely based on local varieties traditionally selected for open field conditions, although, the genetic improvement is a rapidly growing sector toward the development of hybrids. In the present study, nine chilli pepper varieties with diverse market destinations including powder consumption, canned production, and blister packaging as well as seven hybrids obtained through half-diallel crosses between the parent varieties were grown in replicated field trials over diverse locations and evaluated in a comprehensive approach regarding twenty-six quantitative agronomic, morphological and health-related phytochemical traits. Significant differences between hybrids and parents were found for 12 out of the 26 traits studied in both environments. Agronomic and chemical traits did not differ significantly except than for total yield and pH. Several biochemical traits differed significantly and carotenoids and ascorbic acid values were mostly linked to the cultivation environment. A significant effect of the genotype (P < 0.01) was found in all traits for both parental lines and hybrids. The phenotypic plasticity revealed high stability for fruit morphological traits in both parents and hybrids. Greater plasticity was found for total yield in the parent lines, while hybrids were more stable for capsaicinoids and more plastic for carotenoids and AsA, compared to parental. Significant mid-parent heterosis was observed in all the hybrids tested for at least one of the trait evaluated. The PCA in the first two dimensions explained 48.26% of the total variance showing a distinction between each hybrid and the related parental lines for the traits analyzed. This comprehensive approach used, allow to dissect those traits which can be successfully introgressed in hybrids and are useful for precision breeding of novel varieties.
Acrylamide (AA), classified as a probable carcinogen, can be neurotoxic, genotoxic, and can damage DNA. This study explored the ability of seabuckthorn berries juice (SBJ) to alleviate AA‐induced toxic injury in rats. Twenty‐four adult male Sprague‐Dawley (SD) rats were randomly divided into four groups: control group, AA group (40 mg/kg), AA + SBJ (40 mg/kg AA and 5 mL/kg SBJ), and AA + vitamin C (VC) group (positive control group, 40 mg/kg AA and 100 mg/kg VC). At the end of the experiment, rats in AA group showed a marked decrease in the rate of weight gain, hind extremity abduction, and ataxia. Obvious anomalies were seen in plasma biochemical parameters (P < 0.05), and different degrees of injury were observed upon histological examination of five tissues (hippocampus, cerebellum, liver, small intestine, and kidney). Compared to the control group, levels of superoxide dismutase, catalase, and glutathione were significantly decreased, while malondialdehyde was elevated (P < 0.05). SBJ treatment reduced the abnormal of behavior, hematological index, antioxidant enzyme, and tissue damage caused by AA in rats.
Practical Application
Seabuckthorn berries are wild berries rich in vitamin C and polyphenols, which have good antioxidant properties. In this experiment, SBJ has a significant alleviating effect on AA‐induced oxidative damage in rats. Therefore, we speculate that SBJ may relieve the oxidative damage caused by diet or other forms of AA exposure in the general population. At the same time, this experiment also provides new ideas for alleviating AA‐induced in vivo toxicity.
Hot pepper (Capsicum annuum) fruits, usually termed as chili, have been used since ancient times as food vegetables, flavoring ingredients, natural colorants, and in traditional medicines. Nowadays, a wide variation of sweet and pungent peppers are consumed worldwide in a large variety of forms. Interestingly, the most important hot pepper at the global level in commercial terms is C. annuum with a high number of varieties. This review compares C. annuum to other Capsicum species for plant agronomic traits, biochemical composition, the content of capsaicin and capsaicinoids and their nutraceutical and medical potentialities, and the effects of processing on quality and key components of the fruit, among other aspects. Chili contains important levels of pigments (i.e., chlorophyll, anthocyanin, and lutein) with potential health benefits; it also contains additional outstanding health‐promoting chemical compounds, such as vitamins, minerals, flavonoids, carotenoids, and capsaicinoids, in general. And capsaicin, the major active compound responsible for the pungent taste of these species has been proven to have a positive role in health. We report here on how dietary chili and capsaicinoids consumption, especially capsaicin, are involved in body weight reduction and their potential antiobesity effects, in urinary disorders, as well as antioxidants, antimicrobial, anticancer, and analgesic capacity. Selected characteristics of processing for the fruit preservation on its quality and content of these compounds are described as well. However, additional clinical research on the mechanism of action and efficacy of frequent capsaicinoid consumption on human health is needed.
Water supply is a primary contributor to the growth and phytonutrient composition in chili peppers. Several physiological stress factors can influence phytonutrients in chili peppers, resulting in their differential synthesis. Maintaining the right and exact amount of water through a drip system can promote an effective fruit set and crop quality. Four pepper cultivars (‘Hetényi Parázs’; HET, ‘Unikal’; UNIK, ‘Unijol’; UNIJ and ‘Habanero’; HAB) were investigated under different water supply treatments: RF or rain-fed, DI or deficit irrigation, and OWS or optimum water supply. The two-year experiment was carried out in May 2018 and 2019 under open field conditions. Physiological parameters (relative chlorophyll content, chlorophyll fluorescence, and canopy temperature) were measured during the growth stage and phytonutrients (vitamin C, capsaicinoids and carotenoids) analyzed using high-performance liquid chromatography (HPLC) at harvest in September. The study revealed that, due to higher precipitation and rainfall interruption, increased water supply affected physiological response and phytonutrients in the cultivars. HAB under OWS had a lower response during the growth period when compared to HET, UNIK, and UNIJ. As water supply increased, measured individual carotenoid concentration increased in some cultivars. On the other hand, as water supply decreased, vitamin C and capsaicinoids concentration increased. Even though cultivars responded to the water supply treatments differently, HET exhibited a more uniform and stable composition in all treatments.
Citation: Agyemang Duah, S.; Souza, C.S.e; Nagy, Z.; Pék, Z.; Neményi, A.; Daood, H.G.; Vinogradov, S.; Helyes, L. Effect of Water Supply on Physiological Response and Phytonutrient Composition of Chili Peppers. Water 2021, 13, 1284. https://doi.org/10.3390/w13091284
The Capsicum genus is one of the most popular plants consumed and cultivated worldwide, containing approximately 50 000 varieties of pepper. Due to its wide biodiversity, the chemical composition within the genus also presents a great variability. Its major applications are in food and pharmacological industry, as pepper presents a chemical composition rich in capsaicinoids, carotenoids, flavonoids and volatile compounds which is attributed to the ability of the fruit to remove insipidity, produce aromas and act against oxidative diseases. Due the existence of several cultivars there is a huge intraspecific chemical variability within each species, which can be considered as an obstacle when selecting and cultivating a species to be applied as a natural product source for a specific objective. The usage of pepper-based products in different industrial areas requires pre-established ranges of chemical compounds, such as capsaicinoids, which in high concentration are toxic when consumed by humans. Applying a pepper with a chemical profile closely related to the concentration that is required after industrial processing can improve efficacy and effectiveness of the process. An insight into the chemical characteristics of major secondary bioactive compounds within Capsicum, the factors that affect their concentration and their chemosystematic implication are reported and discussed.
As our understanding of the science and functions of color in food has increased, the preferred colorants, forms of use, and legislation regulating their uses have also changed. Natural Colorants for Food and Nutraceutical Uses reflects the current tendency to use natural pigments. It details their science, technology, and applications as well as their nutraceutical properties. Starting with the basics, the book creates an understanding of physical colors, discusses color measurement, and analyzes why natural pigments are preferred today. The authors present an overview of global colorants, including safety, toxicity and regulatory aspects. Information about inorganic and synthetic colorants is included. The book then focuses on applications of natural colorants, with special attention given to characteristics, extraction and processing stability, and the use of biotechnology and molecular biology to increase colorant production. Finally, the book examines the nutraceutical properties of natural colorants and compares them to other well-known nutraceutical components. From the basics to highly specialized concepts and applications, Natural Colorants for Food and Nutraceutical Uses presents essential, practical information about pigments in the food industry. With its coverage of state-of-the-art technologies and future trends in the application of color to food, this book provides the most comprehensive, up-to-date survey of the field.
Colorants: From the Physical Phenomenon to their Nutraceutical Properties: An Overview The Color Phenomenon Definition Human Perception Measurement Pigments Definition A World of Colorless Compounds Pigments in Biology Molecular Affinities of Pigments Natural Distribution of Pigments Classification of Food Colors Choice and Application of Colors Pigments as Food Colorants Colorants as Food Additives Safety of Food Colorants Inorganic and Synthetic Pigments: History, Sources and Uses Inorganic Synthetic Analytical Techniques and the Evaluation of Color Purity Natural Pigments: A Global Perspective Distribution Functions Carotenoids Definition Classification and Nomenclature Distribution Biosynthesis: Biochemistry and Molecular Biology Functions Methodological Aspects Carotenoids as Food Colors Processing and Stability Production of Carotenoids in Bioreactors Anthocyanins and Betalains Anthocyanins Betalains Other Natural Pigments Chlorophylls Caramel Turmeric Cochineal, Carmine and other Natural Pigments from Insects Monascus Iridoids Chemicals and Colorants as Nutraceuticals Fundamentals Nutraceuticals and Related Terms: Definitions Food Items as Nutraceuticals Natural Colorants as Nutraceuticals Nutraceuticals: The Perspective Appendix: List of Abbreviations
In this research 12 different varieties of Capsicum cultivars belonging to three species (Capsicum chinense, Capsicum annuum, Capsicum frutescens) and of various colour, shape, and dimension have been characterised by their carotenoids and capsaicinoids content. The berries were cultivated in the region Emilia-Romagna, in Northern Italy. The native carotenoid composition was directly investigated by an HPLC-DAD-APCI-MS methodology, for the first time. In total, 52 carotenoids have been identified and considerable variation in carotenoid composition was observed among the various cultivars investigated. Among the cultivars with red colour, some Habanero, Naga morich and Sinpezon showed an high β-carotene content, whereas Serrano, Tabasco and Jalapeno showed an high capsanthin content and the absence of β-carotene. Habanero golden and Scotch Bonnet showed a high lutein, α-carotene and β-carotene amounts, and Habanero orange was rich in antheraxanthin, capsanthin and zeaxanthin. Cis-cryptocapsin was present in high amount in Habanero chocolate. The qualitative and quantitative determination of the capsaicinoids, alkaloids responsible for the pungency level, has also been estimated by a validated chromatographic procedure (HPLC-DAD) after a preliminary drying step and an opportune extraction procedure. Results have also been expressed in Scoville units. Dry matter and water activity have also been established on the fresh berries. The dried peppers of each variety were then submitted to the evaluation of the total nitrogen content, measured by a Dumas system, permitting to provide information on the protein content that was found to be in the range between 7 and 16%.
Five cross cultivars of red pepper for paprika and another hot type were compared with a classic sweet variety of pepper from Murcia. Extractable color, moisture, individual carotenoid, red and yellow pigment, and provitamin A content were determined. The results show significant differences between the different cultivars with respect to carotenoid synthesis. There is a good correlation between the moisture content of the cultivars and the provitamin A content and among the carotenoids themselves directly related in the biosynthetic pathway. The results are used as criteria in the selection of cultivars for different industrial processes.
Carotenoid, capsaicinoid and ascorbic acid composition of ripe fruits of five Capsicum annuum cultivars (730 F1, 1245 F1, Amazon F1, Serademre 8 and Kusak 295F1), grown as principle breeding material in Turkey, were quantitatively investigated by means of HPLC technique. Seven main carotenoids, five analogues of capsaicinoids and ascorbic acid were quantified in the fruits grown for 2 year replication. From the capsaicinoids and carotenoids data, Scoville Heat Unit (SHU) and retinol activity equivalent (RAE) values of the fruits were also calculated, respectively. The findings determined that the cultivars of 730 F1 and 1245 F1 had higher carotenoids (2310–2390 mg/kg in dry basis), capsaicinoids (471.3–688.1 mg/kg in dry basis), vitamin A (218.8–243.0 μg RAE/100 g in wet basis) and vitamin C (63.1–64.9 mg/100 g in wet basis) content, without any significant difference among each of them. Furthermore, the cultivars which had higher capsaicinoids contents had higher ascorbic acids content as well. With their high nutritional and functional components, the cultivar of 730 F1 and 1245 F1 can be considered to be selected breeding material for cultivar development.
To simultaneously detect Sudan dyes and carotenoids in red pepper and tomato products, high-performance liquid chromatography (HPLC) methods with photodiode-array detection are developed and validated. The methods include the use of end-capped and nonend-capped adsorbents with a gradient elution system starting with water containing methanol. Water content of 9% in the starting mobile phase is found to be necessary to ensure sufficient separation of Sudan dyes and to avoid overlapping or interference with the carotenoids of considerable content. The data of the validation reveal the accuracy and precision of the developed methods. A limit of Sudan dyes detection of 1-5 microg/g in red pepper or tomato sauce could be approached. The methods provide excellent separation of the carotenoids from the unsaponified extracts of red pepper and the tomato products.
Chromatographic separation of paprika pigments (Capsicum annuum) always faces the problem that oxidation and isomerization may take place during the separation process. Chromatographic separation of individual colour substances from paprika products has been carried out by using mobile phases containing either acetone or chloroform alone or as a gradient system. Various mobile phases were used for simultaneous fractionation of different pigments of paprika on Chromsil C18 column under isocratic conditions. Aceto-nitrile-isopropanol-water (39:57:4) seemed to be the best mobile phase for separation. Detection of individual pigments was carried out at different wavelength by means of a variable wavelength detector of Beckman. Compound identification was achieved by direct scanning of the maximum absorption spectra of each component during HPLC separation as well as by TLC separation. It was found that capsanthin and capsorubin react with fatty acids and form mono and diesters. Quantitative and qualitative changes occuring in the pigments of ground paprika during storage were also studied.
A procedure for the simultaneous, one-step analysis of polar xanthophylls, xanthophyll mono- and diesters and geometric isomers of carotenes in selected fruits and vegetables using high-performance liquid chromatography (HPLC) and photodiode-array detector is described.
The separation of carotenoid extracts was first performed on a column of 6 μm particles using different mobile phases and variable wavelength detectors to monitor column effluents. This procedure had limitations regarding separation efficiency and ease of spectrum analysis during the chromatographic run.
The method was further developed by using a column of 6 μm particles and a mobile phase consisting of acetonitrile-isopropanol-methanol-water (39:52:5:4 v/v/v). This development permitted the isocratic separation of about 45 components in less than 50 minutes. Rapid and precise identification of the individual carotenoids was achieved by using photodiode-array detector under the control of chromatographic software which also allowed for rapid test of peak purity and complete mapping of the whole separation profile including major lipid classes and fat-soluble materials.
A wide variety of carotenoids and carotenoid fatty acid esters were separated and quantified in selected fruits and vegetables such as spice red pepper, tomato, carrot, orange and apricot. cis isomers of β-carotene, the most effective provitamin A, were also separated and differentiated from their corresponding trans forms.
During the last decades comprehensive data in the field of chemistry, biology and technology of spice red pepper (paprika) have rapidly accumulated. In food science and technology the research work focused on, among others, developing accurate, simple, rapid, reliable, and of high sensitivity analytical methods to determine paprika pigments and antioxidants. The research concentrated mainly on the development and optimisation of liquid chromatographic methods to determine the carotenoids, tocopherols (vitamin E) and ascorbic acid (vitamin C). In the area of plant biology/physiology characterisation of ripening of traditional and new cultivars and hybrids of spice red pepper was the main objective of research work carried out by research groups in different countries. In the field of paprika processing and technology special interest has been given to the effect of different drying technologies on the quality components of paprika and their stability during drying, milling and storage. The aim of many research programs was to produce paprika with high colouring capacity, antioxidant content and storage stability. The objective of this article is to review the research works done on spice red pepper in the Central Food Research Institute, Budapest.
Fatty acid carotenoid esters and unesterified hypophasic and epiphasic carotenoids were extracted from paprika fruit at different stages of ripening and processing. The pigments were separated by high-performance liquid chromatography (HPLC) on Chromsil C18 reversed-phase column with 59:57:4 (v/v/v) isocratic conditions and without prior saponificiation of the samples. Monoesters of capsanthin were found to contain mostly unsaturated fatty acids (C18:2) while diesters of both capsanthin and capsorubin contained saturated fatty acids such as C12, C14, and C16. The carotenoid esters were more stable, toward lipoxygenase (LOX) catalyzed linoleic acid oxidation, than free pigments. Furthermore, capsanthin esters containing saturated fatty acids resisted the enzymatic oxidation better than the others did.
Although the biologic actions of carotenoids in human health and their potential use in the prevention of vitamin A deficiency are clear, knowledge is still lacking on routes modulating their absorption and metabolism. One issue concerning both absorption and a key chemical activity of carotenoids (antioxidant capacity) has scarcely been considered: xanthophylls included in our diet are commonly esterified with fatty acids. In this review, the current knowledge of the role of esterification in antioxidant capacity and absorption of carotenoid esters is examined. Although esterification does not change the chromophore properties of the carotenoid molecule, it does modify the immediate molecular environment; thus, chemical activities may be altered depending on the kind of fatty acid bound to the xanthophyll. In particular, the saturated or unsaturated nature of fatty acids is linked with the efficiency of antioxidant action. Moreover, as no carotenoid esters have been detected in plasma and peripheral tissues, they must be hydrolyzed, involving a specific step before absorption. To date, there have been few studies that examined the effect of carotenoid esterification, but this subject is receiving increasing attention. The enzymes involved in the hydrolysis of carotenoid esters are not known, and the suitability of esters as substrate for common lipolytic enzymes is under investigation.
Hot pepper fruits (Capsicum annuum L.) var. Bronowicka Ostra have been studied with regard to content of flavonoids and other phenolics. Nine compounds were isolated from pericarp of pepper fruits by preparative HPLC. Their structures were identified by chromatographic (analytical HPLC) and spectroscopic (UV, NMR) techniques. Two of the identified compounds, trans-p-ferulylalcohol-4-O-(6-(2-methyl-3-hydroxypropionyl) glucopyranoside and luteolin-7-O-(2-apiofuranosyl-4-glucopyranosyl-6-malonyl)-glucopyranoside were found for the first time in the plant kingdom. Additionally compounds: trans-p-feruloyl-beta-D-glucopyranoside, trans-p-sinapoyl-beta- D-glucopyranoside, quercetin 3-O-alpha-L-rhamnopyranoside-7-O-beta-D-glucopyranoside, luteolin 6-C-beta-D-glucopyranoside-8-C-alpha-L-arabinopyranoside, apigenin 6-C-beta-D-glucopyranoside-8-C-alpha-L-arabinopyranoside and luteolin 7-O-[2-(beta-D-apiofuranosyl)-beta-D-glucopyranoside] were found for the first time in pepper fruit Capsicum annuum L.
The major carotenoids and carotenoid esters in Capsicum annuum L. during thermal dehydration of pepper and storage of the ground product (paprika) were examined with special focus on the role of endogenous antioxidants such as vitamins E and C and capsaicinoids, the pungent materials in hot spice red pepper. A high-performance liquid chromatographic (HPLC) method was developed to achieve excellent separation and accurate detection of different carotenoid classes including free xanthophylls, monoesters, carotenes and di-esters. The newly developed method included gradient elution on a reversed-phase column with increasing proportions of isopropanol. The results indicated that presence of capsaicinoids in pungent pepper had a favourable effect on the stability of carotenoids during thermal drying. Among various di-esters those of lutein and zeaxanthine, as well as the mono-ester of β-cryptoxanthin were more stable than those of capsorubin and capsanthin, pointing to the possible role of epoxide and carbonyl groups in the susceptibility of carotenoids. An Arrhenius plot for degradation of carotenoids, tocopherols and ascorbic acid as a function of drying temperature showed linear relationships for all components, with ascorbic acid being the most sensitive. During storage in a refrigerator for 3 months the paprika showed high degradation of all the examined carotenoids particularly in samples prepared from pods dried at high temperatures (90 and 100 °C). An exception was for β-cryptoxanthin mono-ester and violaxanthin di-esters in a non-pungent variety. The amounts of these carotenoids lost during storage were slightly affected by the change in drying temperature. Strong correlation was found between retention of colour in stored paprika and the initial content of ascorbic acid, but not with that of tocopherols or capsaicinoids. Copyright © 2006 Society of Chemical Industry
Gradient and isocratic HPLC separated as many as 38 carotenoid components in extracts from fruit juices. Several oxygenated carotenoids (xanthophylls), hydrocarbon carotenoids, and carotenol mono- and bis-fatty acid esters were identified. Structural elucidation was based on UV/vis spectroscopy, matrix-assisted laser desorption ionization (MALDI) post-source-decay (PSD) mass spectrometry, and comparison with synthetic reference compounds. Straight-chain fatty acid esters (caprate, laurate, myristate, palmitoleate, palmitate, oleate) of β-cryptoxanthin were identified as major carotenoid constituents in tangerine juice concentrate. Fatty acid components were identified by MALDI PSD fragment ion analysis. The xanthophylls violaxanthin, luteoxanthin, neoxanthin, taraxanthin, antheraxanthin, mutatoxanthin, β-cryptoxanthin-5,6:5‘,6‘-diepoxide, lutein, zeaxanthin, α-cryptoxanthin, and β-cryptoxanthin were present in the extracts of saponified tangerine concentrate. The chromatographic profiles of orange juice concentrate showed marked differences from those of tangerine concentrate. In the saponified extract, the oxygenated carotenoid zeaxanthin predominated over β-cryptoxanthin. Keywords: Carotenoids; carotenol esters; carotenoid analysis; mass spectrometry; matrix-assisted laser desorption ionization
Carotenoids and carotenoid esters present in spice paprika powders (Capsicum annuum) were separated and analyzed by high-performance liquid chromatography with a rotating monochromator detector controlled by user-friendly chromatographic software. The carotenoid composition of paprika powders produced from new cross-cultivars was compared with that of powders from the original (Hungarian and Spanish) parents. The results showed significant differences between the new and old cultivars with respect to esterification of carotenoid with fatty acid and the capsanthin/capsorubin ratio. It was also found that the first generation (F-1) from Hungarian red longum and Spanish lilac round cultivars had a carotenoid composition similar to that of its Spanish parent, but the (F-5) subsequent generation gave a yield of improved characteristics such as high color intensity and high capsanthin/capsorubin ratio.
A study was undertaken to investigate the change in carotenoid pigment as well as natural effective antioxidant content of paprika during fruit ripening and storage period of the ground products. By means of modern analytical procedure, paprika fruit was found to contain α-tocopherol in the pericarp and γ-tocopherol in the seeds. Ascorbic acid approached maximum level when the fruit turned red and then declined. Both antioxidants when added to the ground products have substantially reduced color impairment occurring during storage. The color degradation was estimated after 150 days of storage to be 27%, 20%, and 15% at ambient storage conditions and 15%, 13%, and 5% under refrigeration in untreated, δ-tocopherol-treated, and ascorbic acid-treated powders, respectively. Among different paprika cultivars the seeds of F-03 (hot) showed the highest level of tocopherol content, and the powder of such cultivar showed the lowest degradation of carotenoid pigments during storage.
Flavonoid, ascorbic acid and total phenolic content and antioxidant activity of “jalapeño” (Veracruz, Mitla, Tam Mild, Jaloro, Sweet Jalapeño), “yellow wax” [(Hungarian Yellow, Long Hot Yellow, Gold Spike (hybrid)], “Chile” (New Mexico-6, Green Chile), “ancho” (San Luis Ancho), and “serrano” (Hidalgo) peppers were investigated at green or yellow stages of maturity. Major pepper flavonoids were quercetin and luteolin which were present in conjugate forms. Total flavonoid content varied from none detectable to 800 mg/kg after hydrolysis. “Chile”, “yellow wax” and “ancho” peppers had greater flavonoid and ascorbic acid contents and antioxidant activities than “jalapeño” peppers. Sep-Pak C18(tm) bound phenolic compounds, including flavonoids, correlated well with antioxidant activity (r2=0.86). Luteolin had highest antioxidant activity followed by capsaicin and quercetin on equimolar basis.
ABSTRACTA high-performance liquid chromatographic (HPLC) method is described for the simultaneous analysis of E vitamers -, and β-, - and δ-tocopherol and -tocotrienol in seed oils. After diluting the oils with n-hexane, E vitamers are separated by HPLC and detected fluorometrically. Standardization is achieved, using electron-impact mass spectrometry and HPLC. Vitamin E composition of several hot and cold pressed seed oils, originating from maize germs, olives, soy beans and from sesame, safflower and sunflower seeds, was investigated. No clear differences were observed between E vitamer concentrations of hot and cold pressed oils of the same origin. On the other hand, vitamin E composition of oils different origin varied widely. Of the oils examined, only maize germ oil contained -tocotrienol in detectable amounts (about 2%). Esterified E vitamers were not detected.
Alpha and beta carotene, provitamin A activity, dehydroascorbic acid, L-ascorbic acid and total ascorbic acid content of “jalapeño,”“bell,” long green/red “chile,”“serrano” and “yellow wax” peppers (Cupsicum annuum L.) at green and red stages of maturity were determined by HPLC. Effects of thermal processing on vitamin A and C retention in “jalapeno” peppers was also determined. Provitamin A activity ranged from 27.3 to 501.9 Retinol Equivalents (RE/100g). Ascorbic acid concentration ranged from 76.1 to 243.1 (mg/100g). Provitamin A activity and ascorbic acid content increased with maturity in all cultivars. Thermal processing of “jalapeño” cultivars resulted in a 25% decrease of total provitamin A activity and a 75% decrease in total ascrobic acid.
A mathematical model is proposed to simulate the process of drying of individual pieces of red pepper under constant external conditions and to predict changes in some nutritional and organoleptic attributes of the product. The model was solved numerically to obtain moisture content and temperature as well as ascorbic acid and carotenoids concentration in the product as a function of time. A good agreement between predictions and experimental data at different drying temperatures was obtained.Water sorption isotherms of red pepper were determined in the range 20–50 °C and represented by two different sorption equations. Drying kinetics were represented by a diffusive model, the effective moisture diffusivity ranging from 5.01 to 8.32×10−10 m2/s with an activation energy of 23.35 kJ/mol. Degradation kinetics for ascorbic acid and total carotenoids were measured in the range 50–70 °C and modelled as first-order reactions. The rate constants increased with temperature and product moisture content. Average activation energies for carotenoids and vitamin C degradation were 50.1 and 26.9 kJ/mol, respectively.
Iron is an essential metal for normal cellular physiology, but excess iron results in cell injury; it reacts with superoxide anions (O2) and hydrogen peroxide (H2O2) to produce the hydroxyl radical (OH) and other reactive oxygen species (ROS) which can cause damage to body cells. Free radical damage can be prevented by food rich in antioxidants such as fruit and vegetables. In the present study, the ability of aqueous extracts of ripe (red) and unripe (green) hot peppers [Capsicum annuum, Tepin (CAT) and Capsicum chinese, Habanero (CCH)] (3.3–16.7 mg/ml) to prevent 25 μM Fe2+-induced lipid peroxidation in Rat’s brain (In vitro) were assessed using TBARS (Thiobarbituric acid reactive species). The total phenol and vitamin C content, as well as Fe2+-chelating ability, and the ability of the pepper extracts to prevent Fe2+/H2O2-induced decomposition of deoxyribose was also determined. The results of the study revealed that incubating the brain tissues in the presence of 25 μM Fe2+ caused a significant increase (p < 0.05) in MDA (Malondialdehyde) production in the rat’s brain (260%) when compared with the basal (100%). However, the pepper extracts (unripe and ripe) caused a significant decrease (p < 0.05) in the MDA production in both the basal and the Fe2+-induced lipid peroxidation in the Rat’s brain. However, CAT [ripe and unripe] had a significantly (p < 0.05) higher inhibitory effect on both basal and Fe2+-induced lipid peroxidation in the brain tissues than that of CCH (ripe and unripe). In addition, CAT (ripe and unripe) had a significantly higher (p < 0.05) total phenol, vitamin C and Fe2+ chelating ability than CCH (ripe and unripe). The unripe CAT had a significantly (p < 0.05) higher total phenol, Fe2+ chelating ability and inhibitory effect on the basal and Fe2+-induced lipid peroxidation in the brain tissues than the ripe pepper, while the reverse is the case with CCH where the red pepper had a higher values for the same parameters. However, ripe CAT and CCH had a significantly higher (p < 0.05) vitamin C content than the unripe; meanwhile both ripe and unripe peppers (CAT&CCH) did not significantly inhibit (p < 0.05) Fe2+/H2O2-induced decomposition of deoxyribose (Fenton reaction). The inhibitory effect of the pepper on lipid peroxidation (basal and Fe2+ induced) and Fe2+ chelating effect of the extracts were dose dependent. It was therefore concluded that hot peppers prevent Fe2+-induced lipid peroxidation, however CAT (ripe and unripe) are more potent inhibitors of Fe2+-induced lipid peroxidation than CCH (unripe and ripe), meanwhile unripe CAT had the highest protective ability and this is probably due to its higher total phenol content and Fe2+ chelating ability.
A study was conducted to investigate [by high-performance liquid chromatography (HPLC)]the antioxidant vitamin content of paprika during ripening, processing and storage. The most biologically effective antioxidant vitamins, such as ascorbic acid, tocopherols and carotenoids, were separated, identified and quantitated in different samples.The rate of in vivo synthesis of the three antioxidants increased after onset of the ripening process was induced in the climacteric fruits. As ripeness advanced, antioxidant vitamins tended to increase proportionally except that ascorbic acid reached a maximum level at the colour break-II stage and then declined. During drying and storage there was a dramatic decrease in the concentration of tocopherol and ascorbic acid as a result of active antioxidation performance, while carotenoid content decreased at a lower rate.Application of a forced-air drying technique resulted in a significantly high retention of antioxidant vitamins by dried or ground paprika. The different cultivars showed significant differences in their antioxidant vitamin contents.
The carotenoids lutein and capsanthin, widely used as colorants, mainly occur as esters of fatty acids in their producer plants marigold and paprika. The enzymatic hydrolysis of these esters is reported here. Out of 26 commercial lipases, fastest ester hydrolysis under conditions was obtained using an enzyme from Candida antarctica (69% release of capsanthin, 44% of lutein from the respective oleoresins). Bile salts were essential for the activity of all commercial enzymes. A novel hydrolase was discovered in the mycelium-free supernatant of submerged cultures of the edible basidiomycete Pleurotus sapidus. The fungal enzyme cleaved several carotenoid esters almost completely and in the absence of bile salts.
Peppers (Capsicum spp.) were grown for phytochemical analyses at three different locations including a greenhouse at College Station and field plots at Uvalde and Weslaco, Texas. Cultivar effects were significant at each location for all compounds. The best sources of β-carotene were mature greenhouse-grown fruit of Fidel (23.7 μg/g) and C 127 (22.3 μg/g). Mature greenhouse fruit of Tropic Bell (10.1 μg/g) and PI 357509 (9.2 μg/g) had high lutein, but Uvalde field-grown mature fruit of these lines were low in this compound, (1.4 and 0.5 μg/g, respectively). MJ 201 fruit had the highest zeaxanthin levels (10 μg/g) at both College Station and Uvalde. The best sources of quercetin over all locations were the yellow wax types, Banana Supreme (186 μg/g), PI 357509 (86 μg/g) and Rio Grande Gold (26 μg/g). Fidel (37 μg/g) and Banana Supreme (21.5 μg/g) were the best sources of luteolin. Immature fruit generally contained lower levels of lutein and xeaxanthin than mature, colored fruit. These differences were not always statistically significant. Greenhouse-grown peppers at College Station contained more carotenoids than the field-grown peppers in Uvalde and Weslaco, but there were no significant differences among locations for flavonoid concentrations. Several good candidate parents were identified for the breeding program to develop novel pepper varieties with increased health benefits. Families of these varieties are currently being examined to assess the impact of specific environmental factors and identify genes involved in regulating synthesis of these beneficial phytochemicals.
The production of sweet paprika in Spain uses exclusively fruit of Bola-type Capsicum annuum L. This work describes the evaluation of the agronomic behaviour of five new cultivars of the Bola-type paprika red pepper, selected in the Instituto Murciano de Investigación y Desarrollo Agrario y Alimentario (IMIDA), and grown in Extremadura for 3 years. The colour and the pigment content of the paprika elaborated following the traditional procedure of La Vera were also studied.The cultivars studied are very similar in morphology of the plants, and precocity of the crop, also presenting few differences in their yield of fresh and dry red fruit. The cultivars RR-1 and RR-2 had the best yields in dry red fruit, weight of fruit, ripening synchronicity, and resistance of the fruit against rotting. With respect to the parameters of the paprika's quality, the cultivars RR-5, RR-4 and RR-3 stood out in ASTA colour and pigment content. RR-1 and RR-2 are recommended according to the pepper yield, however RR-5, RR-4 and RR-3 cultivars are the best in colour. The recommended cultivars to the growers will depend on the payment criteria of the industry, yield or colour.
Fourteen carotenoids were separated and identified by reversed-phase HPLC in the saponified extract obtained from red pepper fruit, paprika, and oleoresin using gradient elution with acetone and water and UV-visible detection at 450 nm. Quantification was achieved by HPLC with @-apo-8’-carotenal as internal standard. The proposed method minimized artifact formation and permitted easy verification of possible natural or induced transformations as well as any adulteration of the pigments in the commercial presentations: paprika and oleoresin. This method has been used to monitor the changes in the pigments of peppers and in the value of provitamin A at two extreme stages of ripening (green and red) in the Agridulce and Bola varieties. We express our sincere gratitude to CICYT for supporting this research project, ALI91-1166-CO3-02. Peer reviewed
During fruit ripening of pepper (Capsicum annuum), de novo biosynthesis and esterification of carotenoids occur simultaneously. From the very first stages of ripening the totally esterified fraction of xanthophylls is the majority (around 50%). During the ripening process, free xanthophylls decrease in proportion to the rest and at the same time the partial esterified xanthophylls increase in proportion at the expense of the free fraction and simultaneously a portion of the partial esterified xanthophylls are transformed in totally esterified xanthophylls. In the fully ripe fruit the percentages of the free carotenoid pigments and the partially and totally esterified forms of these are 21.3 % ,35.6 % , and 43.1 % , respectively. The fatty acids esterifying yellow xanthophylls are chiefly linoleic ( 18:2A9J2)m, yristic (14:0),a nd palmitic (16:0), whereas in red xanthophylls they are lauric (12:0), myristic (14:0), and palmitic (16:O). This fact helps to explain the greater stability of the red xanthophylls compared to the yellow ones, because of the number of double bonds in the fatty acid chains. We express our sincere gratitude to CICYT (Spanish government) for supporting this research project, ALI 91- 1166-CO3-02. Peer reviewed
Reversed-phase HPLC has been applied to monitor changes in individual carotenoids during the industrial processing of paprika from two pepper varieties, Bola and Agridulce. The ripe fruit, dry fruit, and paprika from the Agridulce variety always show higher carotenoid content than those from the Bola variety. The different stabilities associated with each carotenoid in the industrial processing of paprika are mainly due to intrinsic factors of the variety rather than to processing factors. Whereas in the Agridulce variety the drying and milling stages propitiate a global carotenoid degradation, in the Bola variety carotenoid biosynthesis is detected during the drying step. This biosynthesis is associated with an incomplete maturation of fruit, in such a way that in the Bola variety the drying step induces the synthesis of red pigments from their yellow precursors already present in the fruit. This synthesis is not de novo but a transformation. Irrespective of the variety, red pigments always show greater stability than yellow pigments. The Agridulce variety is more suitable for paprika production since, as well as giving rise to a final product with a greater carotenoid pigment concentration and, therefore, with a more intense color, the final product also has a higher provitamin A content. We express our sincere gratitude to CICYT (Spanish government) for supporting this research project, ALi94- 0777. Peer reviewed
The hypothesis that antioxidant vitamins might decrease the risk of cardiovascular disease (CVD) is a promising area of research. At present, however, it is far from certain whether antioxidant vitamins confer protection against CVD. Evidence for the antioxidant vitamin-cardiovascular disease hypothesis has accumulated from several lines of research. Laboratory research has identified biochemical properties of antioxidant vitamins that could explain their possible role in inhibiting and delaying coronary atherosclerosis. Epidemiologic studies have provided support for the hypothesis by showing that people who consume high amounts of antioxidant vitamins through diet or supplements, or those with high concentrations of these nutrients in their blood, tend to have lower risks of CVD. In the case of the former, however, laboratory findings may not have relevance to free-living humans. Observational epidemiologic studies cannot exclude the possibility that people who consume antioxidant-rich diets or who take vitamin supplements also share other lifestyle or dietary practices that actually account for their lower disease rates. Because of these uncertainties, the only way to determine reliably whether antioxidants play any role in reducing the risk of CVD is to conduct large-scale, randomized trials of these agents, in which adequate doses of antioxidant vitamins are tested for a sufficient duration to allow for any benefits to emerge. Several large-scale trials are now ongoing in both primary and secondary prevention. The results of these trials over the next several years should provide reliable evidence for this promising, but as yet unproven, hypothesis.
Oxidative mechanisms are believed to play an important role in the pathogenesis of age-related eye disease, in particular, cataract and macular degeneration, the two most important causes of visual impairment in older adults. For this reason, there is considerable interest in determining whether vitamins and trace minerals with antioxidant properties can be of benefit in preventing the onset or progression of disabling eye disease. Basic research studies have shown that antioxidants can protect against the cumulative effects of oxidative stress in animal models of cataract and macular degeneration. Data from observational epidemiologic studies in humans, however, are inconclusive. While results from several studies, primarily cross-sectional and case-control, are compatible with a possible protective role for micronutrients in cataract and macular degeneration, data for specific nutrients or specific disease types have often been inconsistent. Further, these observational studies are limited because of the inherent imprecision of dietary exposure data and the likely effects of uncontrolled confounding. Thus, reliable data regarding a potentially important benefit of vitamin supplementation in eye disease will emerge mainly from well-designed, large-scale, randomized trials. Such data are already being collected in the National Eye Institute-sponsored Age Related Eye Disease Study, as well as in the Physicians' Health Study and Women's Health Study.
Changes in xanthophyll esterification degree during pepper fruit ripening have been studied in five cultivars (Numex, Mana, Belrubi, Delfin, and Negral). Esterification of xanthophylls with fatty acids is seen to be a process that is contemporary with and directly linked to the transformation of chloroplast (present in the green fruit) into chromoplast (present in the red fruit). Changes in the fractions of free and partially and totally esterified carotenoids are similar between varieties, reflecting the constitutive nature of esterification as part of the ripening process and being controlled by it. From the first stages of ripening, the fraction of totally esterified pigments (zeaxanthin diester, beta-cryptoxanthin diester, capsanthin diester, and capsorubin diester) makes up almost 50% of the total carotenoid content. The proportion of the partially esterified pigment fraction (zeaxanthin monoester, capsanthin monoester, and capsorubin monoester) in the total carotenoid content increases, with a gradual decrease in the fraction of free pigments (beta-cryptoxanthin, beta-carotene, zeaxanthin, capsanthin, and capsorubin). In the fully ripe stage, a balance is reached between the three esterification fractions (free, partially esterified, and totally esterified), with mean values of 24.17 +/- 4.06, 31.48 +/- 4. 61, and 44.36 +/- 5.05, respectively, which seems to be largely independent of variety. This suggests a marked control of the carotenoid composition of the totally developed chromoplast, indicating its use as an index of ripeness. The inclusion in the present study of a variety (Negral) that retains chlorophylls when ripening, and which shows the same esterification behavior, supports the idea that carotenogenesis is normal and independent of chlorophyll catabolism.
Epidemiologic evidence of a protective role for fruits and vegetables in cancer prevention is substantial. The strength of this scientific base guides US national policymaking in diet and health issues and facilitates community and local programs that address national dietary goals to increase fruit and vegetable consumption. Current scientific evidence also suggests a protective role for fruits and vegetables in prevention of coronary heart disease, and evidence is accumulating for a protective role in stroke. In addition, a new scientific base is emerging to support a protective role for fruits and vegetables in prevention of cataract formation, chronic obstructive pulmonary disease, diverticulosis, and possibly, hypertension. This article provides an overview of the health benefits associated with fruit and vegetable consumption for each of these conditions, including brief discussions of underlying protective mechanisms, identifies key scientific findings regarding the health benefits of fruit and vegetable consumption, and outlines applications of these findings for dietetics professionals. The evidence reviewed provides additional support for increased consumption of a wide variety of vegetables, in particular, dark-green leafy, cruciferous, and deep-yellow-orange ones, and a wide variety of fruits, in particular, citrus and deep-yellow-orange ones. Continued attention to increasing fruit and vegetable consumption is a practical and important way to optimize nutrition to reduce disease risk and maximize good health.
Capsanthin and related carotenoids isolated from the fruits of red paprika Capsicum annuum L. showed potent in vitro anti-tumor-promoting activity with inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). Among them, capsanthin diester and capsorbin diester showed strong inhibitory effects. Furthermore, capsanthin , capsanthin 3'-ester and capsanthin 3,3'-diester , major carotenoids in paprika, exhibited potent anti-tumor-promoting activity in an in vivo mouse skin two-stage carcinogenesis assay using 7, 12-dimethylbenz[a]anthracene as an initiator and TPA as a promoter.
The relationship between the degradation rate and structure of each pigment of the pepper carotenoid profile was studied in mixtures of dehydrated fruit with lipid substrates of differing degrees of unsaturation and in different proportions (20 and 40%). The differences in structural nature of the carotenoids present in the pepper fruit produce a variable rate of oxidation, resulting in nonuniform degradation. The yellow xanthophylls and beta-carotene have the highest rates of oxidation, with the ketocarotenoids and violaxanthin degrading at lower rates. Autoxidation is greater or lesser depending on the functional groups, which stabilize the radical intermediaries of the reaction. The behavior of capsanthin and capsorubin is that expected of carotenoids having structures that include keto groups: a markedly greater stability to autoxidation processes. This increases their antioxidant capacity, adding to their beneficial impact by reducing the proliferation of radical processes, which are detrimental to health.
Four cultivars (Bronowicka Ostra, Cyklon, Tornado, and Tajfun) of pepper fruit Capsicum annuum L. were studied for phenolics contents and antioxidant activity. Two fractions of phenolics, flavonoids (with phenolic acids) and capsaicinoids, were isolated from the pericarp of pepper fruit at two growth stages (green and red) and were studied for their antioxidant capacity. Both fractions from red fruits had higher activities than those from green fruits. A comparison of the capsaicinoid fraction with the flavonoid and phenolic acid fraction from red fruit with respect to their antioxidant activity gave similar results. Phenolic compounds were separated and quantified by LC and HPLC. Contents of nine compounds were determined in the flavonoid and phenolic acid fraction: trans-p-feruloyl-beta-d-glucopyranoside, trans-p-sinapoyl-beta-d-glucopyranoside, quercetin 3-O-alpha-l-rhamnopyranoside-7-O-beta-d-glucopyranoside, trans-p-ferulyl alcohol-4-O-[6-(2-methyl-3-hydroxypropionyl] glucopyranoside, luteolin 6-C-beta-d-glucopyranoside-8-C-alpha-l-arabinopyranoside, apigenin 6-C-beta-d-glucopyranoside-8-C-alpha-l-arabinopyranoside, lutoeolin 7-O-[2-(beta-d-apiofuranosyl)-beta-d-glucopyranoside], quercetin 3-O-alpha-l-rhamnopyranoside, and luteolin 7-O-[2-(beta-d-apiofuranosyl)-4-(beta-d-glucopyranosyl)-6-malonyl]-beta-d-glucopyranoside. The main compounds of this fraction isolated from red pepper were sinapoyl and feruloyl glycosides, and the main compound from green pepper was quercetin-3-O-l-rhamnoside. Capsaicin and dihydrocapsaicin were the main components of the capsaicinoid fraction. A high correlation was found between the content of these compounds and the antioxidant activity of both fractions. Their antioxidant activities were elucidated by heat-induced oxidation in the beta-carotene-linoleic acid system and the antiradical activity by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) decoloration test. The highest antioxidant activity in the beta-carotene-linoleic acid system was found for trans-p-sinapoyl-beta-d-glucopyranoside, which was lower than the activity of free sinapic acid. Quercetin 3-O-alpha-l-rhamnopyranoside had the highest antiradical activity in the DPPH system, which was comparable to the activity of quercetin. The activities of capsaicin and dihydrocapsaicin were similar to that of trans-p-feruloyl-beta-d-glucopyranoside in the DPPH model system.
Carotenoids comprise a class of natural fat-soluble pigments which are found in numerous fruits and vegetables. The consumption of a diet rich in carotenoids has been epidemiologically correlated with a lower risk for several diseases. The antioxidant activity of carotenoids and biochemical properties influencing signaling pathways have been discussed as basic mechanisms of prevention. Conflicting data from intervention studies with beta-carotene to prevent cancers and cardiovascular disorders have challenged the concept. However, there is convincing evidence that carotenoids are important components of the antioxidant network. Photooxidative damage is suggested to be involved in the pathobiochemistry of several diseases affecting the skin and the eye, and carotenoids may protect light-exposed tissues. Lutein and zeaxanthin are the predominant carotenoids of the retina and are considered to act as photoprotectants preventing retinal degeneration. The unique distribution, localization and high levels of both carotenoids within the macula lutea as well as their physicochemical properties make them suitable candidates for photoprotection. beta-Carotene is used as an oral sun protectant for the prevention of sunburn and has been shown to be effective either alone or in combination with other carotenoids or antioxidant vitamins. Protective effects are also achieved with a diet rich in lycopene.
Combined chronic toxicity and carcinogenicity studies of paprika color, used as a food additive in various countries, were performed in male and female F344 rats. Dietary concentrations of 0%, 0.62%, 1.25%, 2.5% and 5% were applied in a 52-week toxicity study and 0%, 2.5% and 5% in a 104-week carcinogenicity study. Treatment with paprika color caused a significant increase in incidence of hepatocellular vacuolation in 5% males, but no toxicological effects were found with reference to survival rates, body weights, hematological or serum biochemical parameters and organ weights at any dose level in either sex in the chronic toxicity study. Also, paprika color did not induce specific tumors nor did it exert significant influence on the development of spontaneous tumors in any of the organs examined in the carcinogenicity study. In conclusion, based on slight histopathological changes observed in 5% male livers, the no-observed-effect level (NOEL) was estimated to be 2.5% in the diet (1,253 mg/kg bw/day) and the no-observed-adverse-effect level (NOAEL) was determined to be 5% in the diet (2,388 mg/kg bw/day) for male rats, and for females, the NOEL was concluded to be 5% in the diet (2,826 mg/kg bw/day). Additionally, paprika color was not carcinogenic to male and female F344 rats under the present experimental conditions.
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