Carotenoid Content and Profiles of Pumpkin Products and By-Products

Carotenoids from Different Pumpkin Varieties Exert a Cytotoxic Effect on Human Neuroblastoma SH-SY5Y Cells

Plants, including pumpkins (Cucurbita spp.), are an interesting source of nutrients and bioactives with various health benefits. In this research, carotenoid extracts obtained from the pulp of eight pumpkin varieties, belonging to the C. moschata and C. maxima species, were tested for cytotoxicity on SH-SY5Y neuroblastoma cells. The results showed that pumpkin bioactives exert a cytotoxic action against the tested cells, in particular Butternut extract at a 100 μM (53.69 μg/mL) concentration after 24 h of treatment and Mantovana extract at 50 μM (26.84 μg/mL) after 48 h. Moreover, the carotenoid extracts also showed interesting in vitro antioxidant activity, evaluated by ABTS and ORAC assays. To fully characterize the qualitative and quantitative profile of carotenoids in the tested extracts, a high-performance chromatographic technique was performed, revealing that pumpkin pulp carotenoids were mainly represented by β-carotene, mono- and di-esterified hydroxy- and epoxy-carotenoids. Moreover, the carotenoid dataset was also useful for discriminating samples from two different species. In conclusion, the results of the present study highlight the potential anti-cancer activity of pumpkin carotenoid extracts and the possibility of using them as chemotherapeutic adjuvants.

Pumpkin and Pumpkin By-Products: A Comprehensive Overview of Phytochemicals, Extraction, Health Benefits, and Food Applications

A versatile and popular Cucurbitaceous vegetable, pumpkin has recently gained much attention because of its variety of phytochemicals and health advantages. Pumpkins are a type of winter squash, traditionally with large, spherical, orange fruits and a highly nutrient food. Pumpkin by-products comprise various parts, such as seeds, peels, and pulp residues, with their bioactive composition and many potential benefits poorly explored by the food industry. Pumpkin and their by-products contain a wide range of phytochemicals, including carotenoids, polyphenols, tocopherols, vitamins, minerals, and dietary fibers. These compounds in pumpkin by-products exhibit antioxidant, anticancer, anti-inflammatory, anti-diabetic, and antimicrobial properties and could reduce the risk of chronic diseases. This comprehensive review aims to provide a detailed overview of the phytochemicals found in pumpkin and its by-products, along with their extraction methods, health benefits, and diverse food and industrial applications. This information can offer valuable insights for food scientists seeking to reevaluate pumpkin's potential as a functional ingredient. Reusing these by-products would support integrating a circular economy approach by boosting the market presence of valuable and sustainable products that improve health while lowering food waste.

Map-based cloning reveals Cpgp gene encoding an APRR2 protein to regulate the green fruit peel formation in Cucurbita pepo

Fruit peel color is a major factor that influences fruit quality and customers' demand. However, the molecular mechanisms underlying the green fruit peel color trait of Cucurbita pepo L. remain unknown. Two parental lines, RP16 and RP38, were used to study the fruit peel color trait in C. pepo. The parental line RP16 shows white peel color, whereas RP38 exhibits green peel color. 384 F2 populations were used to identify the inheritance pattern associated with green fruit and white fruit peel in Cucurbita pepo L. 293 F2 individuals were white, and 91 F2 individuals were green, resulting in a ratio of 3:1. Hence, white peel is dominant over the green fruit peel trait, and a single recessive green peel gene (Cpgp) controls the green fruit peel. The fruit chlorophyll (Chll) content decreases as fruit matures in the RP16 line. In contrast, Chll increases during the fruit growing periods on fruit peels of the RP38 line. The BSA-sequence analysis revealed the Cpgp locus on Chr5, within a 2.3 Mb region. Subsequent fine-mapping analysis, using 699 F2 plants, narrowed down this region to 23.90 kb on the same chromosome. Within this region, two annotated genes, namely Cp4.1LG05g02070 and Cp4.1LG05g02060, are present. These genes are predicted to encode a two-component Arabidopsis Pseudo-Response Regulator 2-like protein (APRR2), which may be involved in green pigmentation processes in plants. Consequently, sequence alignment and gene expression analyses at various fruit development stages supported that Cp4.1LG05g02070 may be the primary candidate gene responsible for regulating the green fruit peel color trait in Cucurbita pepo L. This study may provide a basis for further study on the basic mechanisms that control the fruit peel colors in Cucurbita spp.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11032-024-01492-7.

Optimization of the Parameters Influencing the Antioxidant Activity and Concentration of Carotenoids Extracted from Pumpkin Peel Using a Central Composite Design

It has been discovered that the peel of a pumpkin (Cucurbita maxima), regarded as a waste product of pumpkin processing, has significant amounts of carotenoids and other antioxidants. This study aims to identify the most effective extraction parameters for an ultrasonic-assisted extraction method to extract the total carotenoids (TCs) and assess the antioxidant activity (AA) of pumpkin peel. To determine the effects of the extraction time, temperature, and material-to-solvent ratio on the recovery of TCs and AA, a response surface methodology utilizing the central composite design (CCD) was used. The extraction temperature (6.25-98.75 °C), extraction duration (13.98-128.98 min), and solvent ratio (0.23-50.23 mL) were the variables studied in the coded form of the experimental plan. The carotenoid concentration varied from 0.53 to 1.06 mg/g DW, while the AA varied from 0.34 to 7.28 µM TE/g DW. The findings indicated that the optimal extraction parameters were an 80 °C temperature, a 10 mL solvent ratio, and a 100 min extraction time. The study confirmed that the optimum extraction conditions resulted in an experimental TC yield of 0.97 mg/g DW and an AA of 7.25 µM TE/g DW. Overall, it should be emphasized that the extraction process can be enhanced by setting the operating factors to maximize the model responses.

Genome‑wide analysis of the MYB gene family in pumpkin

The MYB gene family exerts significant influence over various biological processes and stress responses in plants. Despite this, a comprehensive analysis of this gene family in pumpkin remains absent. In this study, the MYB genes of Cucurbita moschata were identified and clustered into 33 groups (C1-33), with members of each group being highly conserved in terms of their motif composition. Furthermore, the distribution of 175 CmoMYB genes across all 20 chromosomes was found to be non-uniform. Examination of the promoter regions of these genes revealed the presence of cis-acting elements associated with phytohormone responses and abiotic/biotic stress. Utilizing quantitative real-time polymerase chain reaction (qRT-PCR), the expression patterns of 13 selected CmoMYB genes were validated, particularly in response to exogenous phytohormone exposure and various abiotic stressors, including ABA, SA, MeJA, and drought treatments. Expression analysis in different tissues showed that CmoMYB genes are expressed at different levels in different tissues, suggesting that they are functionally divergent in regulating growth and abiotic stresses. These results provide a basis for future studies to characterize the function of the MYB gene family under abiotic stresses in pumpkins.

Influence of Different Drying Processes on the Chemical and Texture Profile of Cucurbita maxima Pulp

The effects of hot air (HAD), vacuum (VAD) and conductive (CD) drying on the chemical and textural profiles of Cucurbita maxima pulp were investigated to find suitable drying conditions to avoid postharvest losses of pumpkin. The results showed that the drying methods had a significant effect (p < 0.05) on the chemical and textural profiles of pumpkin pulp. The ash content was lower in VAD (up to 7.65%) than in HAD (up to 9.88%) and CD pulp (up to 9.21%). The samples of HAD, CD and VAD had a higher fat content, up to 3.07, 2.66 and 2.51%, respectively, than fresh pulp (1.55%). The total fibre content is lower for VAD (up to 8.78%) than for HAD (up to 15.43%) and CD pulp (13.94%). HAD pulp at 70 °C (~15.51%) and VAD and CD pulp processed between 50 and 60 °C (~22%) are good sources of protein. HAD and CD pulp at 70 °C and VAD at 50 °C resulted in a high sugar content (up to 83.23%). In addition to drying, the extraction time of 40 min used in ultrasound-assisted extraction is optimal, especially for protein and sugar recovery in dried samples. Drying also led to strong changes in the textural properties of the pulp, so that an excellent dried intermediate product is the one obtained using HAD at a temperature of 70 °C and an airflow of 0.5 m/s.

Integrated metabolome, full-length sequencing, and transcriptome analyses unveil the molecular mechanisms of color formation of the canary yellow and red bracts of Bougainvillea × buttiana 'Chitra'

Bougainvillea is a typical tropical flower of great ornamental value due to its colorful bracts. The molecular mechanism behind color formation is not well-understood. Therefore, this research conducted metabolome analysis, transcriptome analysis, and multi-flux full-length sequencing in two color bracts of Bougainvillea × buttiana 'Chitra' to investigate the significantly different metabolites (SDMs) and differentially expressed genes (DEGs). Overall, 261 SDMs, including 62 flavonoids and 26 alkaloids, were detected, and flavonols and betalains were significantly differentially accumulated among the two bracts. Furthermore, the complete-length transcriptome of Bougainvillea × buttiana was also developed, which contained 512 493 non-redundant isoforms. Among them, 341 210 (66.58%) displayed multiple annotations in the KOG, GO, NR, KEGG, Pfam, Swissprot, and NT databases. RNA-seq findings revealed that 3610 DEGs were identified between two bracts. Co-expression analysis demonstrated that the DEGs and SDMs involved in flavonol metabolism (such as CHS, CHI, F3H, FLS, CYP75B1, kaempferol, and quercetin) and betacyanin metabolism (DODA, betanidin, and betacyanins) were the main contributors for the canary yellow and red bract formation, respectively. Further investigation revealed that several putative transcription factors (TFs) might interact with the promoters of the genes mentioned above. The expression profiles of the putative TFs displayed that they may positively and negatively regulate the structural genes' expression profiles. The data revealed a potential regulatory network between important genes, putative TFs, and metabolites in the flavonol and betacyanin biosynthesis of Bougainvillea × buttiana 'Chitra' bracts. These findings will serve as a rich genetic resource for future studies that could create new color bracts.

Effects of including of Japanese Pumpkin Seeds and Pomace in the Diets of Pacific White Shrimp (Penaeus vannamei)

A 60-day feeding trial was conducted to evaluate the effects of including pumpkin seeds and pomace in the diets of Pacific white shrimp Penaeus vannamei, and the effects of these supplements on growth performance, body composition, and total polyphenol, flavonoid and carotenoid contents, as well as on total antioxidant activity, and body color parameters. Five diets were evaluated: pumpkin seeds (PS) at 50 and 100 g·kg-1, pumpkin pomace (PP) at 50 and 100 g·kg-1, and a control treatment. Pacific white shrimp (P. vannamei) juveniles (0.60 ± 0.01 g) were stocked in 15 tanks (310 L), containing 30 shrimps per tank, and the treatments were randomly distributed in triplicate. At the end of the experiment, shrimps were euthanized, weighed, and dissected for further analyses. The inclusion of PS in the diets impaired growth performance, reduced the total flavonoid content and had a pro-oxidative effect on muscle. The inclusion of PP in the diets did not affect growth performance, improved the feed conversion ratio, increased the total flavonoid content in the diets and hepatopancreas, and improved the antioxidant activity of the feeds and shrimp muscle. The total carotenoid content of the feeds increased with the inclusion of PS or PP in the diets; however, the total carotenoid content of shrimp increased only in those fed PP diets. Shrimp fed with PS diets showed a yellowish color and higher saturation when fresh and a reddish color and yellow hue angle after cooking. Shrimp fed PP diets turned reddish and yellowish, both when fresh and after cooking. The inclusion of PS in P. vannamei diets is not recommended; however, PP can be included at 100 g·kg-1 without affecting the growth parameters. Further studies evaluating the inclusion of higher PP levels in shrimp diets are recommended.

Effect of Bioactive Compounds from Pumpkin Powder on the Quality and Textural Properties of Shortbread Cookies

The problem of food with functional ingredients, characterized by low energy intake and a variety of phytonutrients with biological activity, is one of the concerns of the population. The objectives of this study were to investigate the effect of pumpkin powder and its bioactive components on the quality, color and textural properties of shortbread cookies. In the drying process of pumpkin powder (Cucurbita moschata) at 60 ± 2 °C, the physicochemical parameters did not change significantly in relation to fresh pulp. The chromatic parameters L*, a* and b* showed that the pumpkin powder was brighter than the pulp, with a greater presence of yellow pigments. Pumpkin powder presented a rich source of bioactive compounds (polyphenols flavonoids, carotenoids) with an antioxidant potential of 161.52 mmol TE/100 g DW and 558.71 mg GAE/100 g DW. Antimicrobial activity against Gram-positive (Staphylococcus aureus, Bacillus cereus), Gram-negative (Escherichia coli, Salmonella Abony and Pseudomonas aeruginosa) bacteria and high antifungal activity against Candida albicans were attested. The sensory, physicochemical, texture parameters and color indicators of shortbread cookies with yellow pumpkin powder (YPP) added in a proportion of 5-20% were analyzed. The optimal score was given to the sample of 15% YPP. The use of 15-20% YPP contributed to improved consistency due to the formation of complexes between starch and protein.

Analysis of Nutritional Characteristics and Willingness to Pay of Consumers for Dry-Cured Sausages (Salchichón) Made with Textured Seed Oils

The consumption of processed meat products beyond recommended limits has been associated with serious health conditions, including heart disease, diabetes, and cancer. In an effort to create healthier options, the meat industry is exploring alternatives to animal fat in processed meats. This study focuses on replacing animal fat in dry-cured sausages (Salchichón) with textured chia, poppy, melon, and pumpkin oils. The research aims to evaluate the physical and nutritional changes resulting from this substitution and assess consumer acceptance through sensory analysis. The use of seed oils led to slight color changes and comparable texture, except for cohesiveness. The incorporation of textured seed oils resulted in reduced fat content, increased proportions of ashes and protein, and decreased energy value. The fatty acid composition showed lower proportions of saturated fatty acids and increased polyunsaturated fatty acids. Sensory analysis revealed that the control sample with pork fat received the highest ratings for appearance, texture, and taste, while samples with higher seed oil percentages scored lower due to color, cohesiveness, and specific flavors from the seed oils. Despite these variations, consumers demonstrated a high level of acceptability for all samples. Choice analysis results indicated that higher prices had a negative impact on consumer willingness to purchase, while the use of the 100% Iberian pig breed and animal welfare labels positively influenced purchasing attitudes. Regarding the presence of a pumpkin seed oil label in the product, a negative willingness to pay was reported. However, significant individual variation was reported for this attribute, indicating the existence of consumer segments with more positive attitudes toward these innovative dry-cured sausages.

Physical and Chemical Properties of Vegetable Films Based on Pumpkin Purée and Biopolymers of Plant and Animal Origin

Highly methylated apple pectin (HMAP) and pork gelatin (PGEL) have been proposed as gelling agents for pumpkin purée-based films. Therefore, this research aimed to develop and evaluate the physiochemical properties of composite vegetable films. Granulometric analysis of film-forming solutions showed a bimodal particle size distribution, with two peaks near 25 µm and close to 100 µm in the volume distribution. The diameter D_4.3, which is very sensitive to the presence of large particles, was only about 80 µm. Taking into account the possibility of creating a polymer matrix from pumpkin purée, its chemical characteristic was determined. The content of water-soluble pectin was about 0.2 g/100 g fresh mass, starch at the level of 5.5 g/100 g fresh mass, and protein at the level of about 1.4 g/100 g fresh mass. Glucose, fructose, and sucrose, the content of which ranged from about 1 to 1.4 g/100 g fresh mass, were responsible for the plasticizing effect of the purée. All of the tested composite films, based on selected hydrocolloids with the addition of pumpkin purée, were characterized by good mechanical strength, and the obtained parameters ranged from about 7 to over 10 MPa. Differential scanning calorimetry (DSC) analysis determined that the gelatin melting point ranged from over 57 to about 67 °C, depending on the hydrocolloid concentration. The modulated differential scanning calorimetry (MDSC) analysis results exhibited remarkably low glass transition temperature (Tg) values, ranging from -34.6 to -46.5 °C. These materials are not in a glassy state at room temperature (~25 °C). It was shown that the character of the pure components affected the phenomenon of water diffusion in the tested films, depending on the humidity of the surrounding environment. Gelatin-based films were more sensitive to water vapor than pectin ones, resulting in higher water uptake over time. The nature of the changes in water content as a function of its activity indicates that composite gelatin films, with the addition of pumpkin purée, are characterized by a greater ability to adsorb moisture from the surrounding environment compared to pectin films. In addition, it was observed that the nature of the changes in water vapor adsorption in the case of protein films is different in the first hours of adsorption than in the case of pectin films, and changes significantly after 10 h of the film staying in an environment with relative humidity RH = 75.3%. The obtained results showed that pumpkin purée is a valuable plant material, which can form continuous films with the addition of gelling agents; however, practical application as edible sheets or wraps for food products needs to be preceded with additional research on its stability and interactions between films and food ingredients.

Effects of Ginger and Garlic Powders on the Physicochemical and Microbiological Characteristics of Fruit Juices during Storage

Natural preservatives such as garlic and ginger can be added to the formulation of fresh fruit juices to encourage the consumption of health-promoting foods. In this study, the influence of garlic and ginger and the storage conditions on physicochemical and microbiological characteristics of fruit juices were investigated. The fruit juice assortments were produced from apple, apple and pumpkin, and apple and pomegranate and were treated with 0.5 g garlic powder, 0.5 g ginger powder, and 0.25 g mix of garlic and ginger powders. A total of 12 unpasteurized samples were produced, of which 3 were control samples. Samples stored at 20 and 4 °C were analyzed at 0, 3, 6, and 9 days for water activity (aw), pH, titratable acidity (TA), total soluble solids (TSS), electrical conductivity (EC), vitamin C, color parameters, total number of germs, yeasts, and molds, Listeria, Enterobacteriaceae, and Escherichia coli. Results showed that aw, pH, TSS, and vitamin C content decreased during storage of fruit juice samples, while TA increased. The lowest increase in total number of aerobic mesophilic germs was determined for the apple and pumpkin juice with garlic and ginger and apple juice with garlic.