Search Results (41)

During fruit ripening in Capsicum species, substantial amounts of carotenoids accumulate in the pericarp. While the carotenoid biosynthesis pathway in Capsicum species has been extensively investigated from various angles, the transcriptional regulation of genes encoding carotenoid biosynthetic enzymes remains less understood in this non-climacteric horticultural crop compared to tomato, a climacteric fruit. In the present study, we investigated the function of the NAM, ATAF1/2 or CUC2 81 (CaNAC81) transcription factor gene. This gene was selected through RNA-Seq co-expression analysis based on the correlation between expressed transcription factor gene profiles and those of carotenoid structural genes. To determine its role in regulating the expression of biosynthetic-related carotenogenic genes, we performed Virus-Induced Gene Silencing (VIGS) assays in the Serrano-type C. annuum ‘Tampiqueño 74’. Fruits from plants infected with a pTRV2:CaNAC81 construct (silenced fruits) exhibited altered carotenoid pigmentation accumulation, manifested as yellow-orange spots, in contrast to fruits from non-agroinfected controls (NTC) and fruits from plants infected with the empty TRV2 construct (red fruits). Quantitative real-time PCR (qPCR) assays confirmed decreased transcript levels of CaNAC81 in fruits displaying altered pigmentation, along with reduced transcription of the PSY gene, which encodes the carotenoid biosynthetic enzyme phytoene synthase (PSY). High-performance liquid chromatography (HPLC) analysis revealed a distinct carotenoid pigment accumulation pattern in fruits from plants showing silencing symptoms, characterized by low concentrations of capsanthin and zeaxanthin and trace amounts of capsorubin, compared to control plants (NTC). These findings suggest the involvement of CaNAC81 in the regulatory network of the carotenoid biosynthetic pathway in chili pepper fruits. Full article

Aflatoxin contamination poses a significant food safety risk, particularly during the storage of dried chili peppers. This study evaluated the efficacy of formic acid treatment, ultraviolet (UV) treatment, and combined UV-formic acid treatment in both preventing and controlling Aspergillus flavus in dried red chili powder. Efficacy was assessed by measuring the growth diameter of A. flavus colonies on un-colonized and already colonized dried red chili powder. The optimal treatment conditions for the UV-formic acid combination were determined through single-factor experiments, orthogonal experiments, and quality assessment. Finally, the effects of the UV-formic acid combination on the cell membrane, antioxidant system, and energy metabolism of A. flavus were investigated. The results revealed that fumigation of un-colonized dried red chili powder with 5% formic acid for 24 h inhibited A. flavus growth by 93.29% and toxin synthesis by 99.41%. In contrast, treatment of already colonized chili powder with 10% formic acid inhibited A. flavus colony growth by 50%. Through a three-factor, three-level orthogonal experiment followed by quality testing, the optimal conditions were determined to be 8% formic acid concentration, a UV irradiation distance of 15 cm, and a treatment time of 75 min. This optimized combined treatment reduced the required fumigation time from 24 h to 1.25 h. This technique achieved complete suppression of aflatoxin B₁ synthesis on un-colonized dried red chili powder. On already colonized chili powder, the mycelial growth inhibition rate was 48.05 ± 6.68%, and aflatoxin B₁ synthesis was inhibited by 91.32 ± 3.15%. Quality assessment revealed that the UV-formic acid co-treatment parameters did not significantly affect key quality indicators including color, capsaicin content, total phenolic content (p > 0.05). Furthermore, UV-formic acid treatment disrupt the cell membrane structure of A. flavus, impairs its antioxidant and energy metabolism systems, and induces mitochondrial dysfunction. The study confirmed the synergistic antifungal effect of formic acid and UV, providing a potential industrialized solution for enhancing the safety and storage stability of dried chili products. Full article

Dihydrocapsaicin (DHC), a prominent capsaicinoid derived from red chili peppers, has shown cytotoxic effects against various cancer cell types. However, its role in modulating cytokine-induced survival and apoptotic signaling in cancer cells remains unclear. In this study, we investigated the effects of DHC on tumor necrosis factor-α (TNF-α)-induced cell cycle arrest and apoptosis in HeLa human cervical cancer cells. Our results demonstrate that DHC significantly enhances TNF-α-induced G1 phase cell cycle arrest and apoptosis by targeting the transforming growth factor-β-activated kinase 1 (TAK1)-mediated prosurvival pathways. DHC inhibited the phosphorylation of TAK1 and downstream effectors including IKKα, NF-κB p65, MAPKs (p38, JNK, ERK), Akt, and EGFR, thereby disrupting key signaling networks that typically confer resistance to TNF-α-induced cytotoxicity. Additionally, DHC suppressed the TNF-α-induced phosphorylation of EGFR at Ser-1046/1047 and Thr-669, sites critical for survival signaling. Co-treatment with DHC and TNF-α led to enhanced apoptotic features, including increased PARP-1 cleavage. These findings suggest that DHC sensitizes cervical cancer cells to cytokine-induced cell death by interfering with TAK1/NF-κB and EGFR signaling axes. Our study positions DHC as a promising candidate for combination therapies aimed at overcoming resistance in cancers with aberrant inflammatory and survival signaling. Full article

The production of spicy sauces from chili peppers (Capsicum spp.) generates 5–30% of spicy by-product which is rich in valuable compounds (e.g., capsaicinoids, carotenoids, phenolics, etc.) and can serve as a source of Capsicum oleoresins, providing spice and color ingredients for food products. This study primarily focused on the optimization of Capsicum oleoresin extraction from Red Habanero chili pepper (Capsicum chinense Jacq.) by-product using ultrasound-assisted extraction (UAE). A second focus was the comparison between UAE and reflux-assisted extraction (RAE). Response Surface Methodology (RSM) was employed to optimize the extraction time (3 to 17 min) and acoustic power density (APD, 0.30 to 1.00 W/mL). The optimal UAE conditions (8 min, 0.87 W/mL) showed a higher extraction yield (26%) and high quality oleoresin extracts rich in bioactives (capsaicinoids: 7 mg/g; phenolics: 4 mg GAE/g) with antioxidant activity (FRAP: 139 µmol FeSO₄ eq/g; DPPH: 33 µmol TEAC/g). Optimum UAE extracts proved more colored, energy-efficient (95% less consumption), equally spicy (466,000 SHU) and had higher antioxidant activity than RAE. These results demonstrated UAE as a sustainable method for producing high value spicy additives from chili pepper by-product, turning them into products with enhanced bioactivity, favoring a circular economy in the agri-food industry. Full article

Pigments in plants not only determine their visual characteristics but also play crucial roles in photosynthesis, pollinator attraction, and disease resistance. The diverse colors of chili peppers arise from various pigments. However, detailed reports on the genetic and metabolic changes of these pigments in the developmental stages of colorful chili peppers are limited. In this study, we analyzed the content of anthocyanins and carotenoids in the fruits of the cultivated pepper variety H18 at different growth and development stages. Our findings revealed that, as the fruits mature, the anthocyanin content gradually decreases while the carotenoid content increases. Using the transcriptomic and metabolomic sequencing of pepper fruits at various developmental stages, we identified four types of anthocyanins: pelargonidin, cyanidin, delphinidin, and peonidin, as well as a small amount of proanthocyanidins. The concentrations of these anthocyanins generally showed a decreasing trend, and the expression patterns of anthocyanin biosynthesis genes were consistent with the metabolic data. In the analysis of carotenoids, we found that, apart from Lutein, the concentrations of all other detected carotenoids increased during fruit development. Most carotenoids began to accumulate significantly at the orange fruit stage (H18-O) and peaked at the red fruit stage (H18-R). Transcriptomic and RT-qPCR data indicated that the expression of carotenoid biosynthesis genes also increased progressively. Furthermore, we investigated the degradation of anthocyanins and identified potential degradation genes, including BGLU, POD, and PPO. This study provides deep insights into the mechanisms underlying pigment changes in colorful peppers, which may contribute to the improvement of pepper varieties and future research on pigment regulatory mechanisms. Full article

Quantification of free and bound carotenoids in pigmented fruit and vegetable matrices has previously been challenging due to carotenoid instability, degradation during extraction, and the prevalence of predominant carotenoid esters. The aim of the present study was to develop an optimized extraction procedure that minimises the loss of free and bound carotenoids by utilising a combination of extraction solutions, followed by an improved saponification process. A mixture of hexane, dichloromethane, ethanol and water achieved the highest extraction efficiency (>97%) from the chili/capsicum matrix. The study also addressed the previously unexplained loss of carotenoids during saponification by adding phosphate buffer to the sample–extract mixture, which prevented soap micelle formation. Additionally, the duration and temperature of the saponification procedure and pH of the final extraction solution were further optimised to achieve a higher total carotenoid recovery. A total of 48 free and bound carotenoids were identified in the capsicum fruit samples using UHPLC-DAD-MS/MS. The total carotenoid content within six bell pepper and chili fruits ranged between 1.63 (green bell capsicum) and 32.08 mg/100 g fresh weight (sweet red baby capsicum). The current methodology potentially could be used in a broad range of different carotenoid-containing matrices and commodities. Full article

Pungent red peppers and chilis are healthy foods and crucial ingredients of modern diets due to their content of bioactive phytochemicals such as carotenoids, tocopherols, capsaicinoids, polyphenols, and vitamin C. The production of pungent peppers with outstanding nutritional properties is influenced by genetic factors and their interaction with the environments where they are cultivated. This study was conducted to investigate the effects of genotype and climate conditions on the response of capsaicinoids and vitamin C. The extracts of pungent materials and vitamin C were separated and qualitatively determined by HPLC alone or hyphenated with mass spectroscopy. Four genotypes were selected and cultivated under traditional agricultural practices in southern Hungary. The yield properties and the contents of capsaicinoids and vitamin C were significantly influenced by genetic factors and, to a high extent, by the interaction between genotype × environment. The highest yield of 2.86 ± 0.59 kg/m² was recorded for the CS variety. The yield was significantly decreased under high precipitation and low air temperature. The highest concentration of capsaicin of 1586–1734 µg/g dwt was found in the BHJ variety. The lowest level of 514 µg/g dwt of capsaicin was determined in the CS variety, in which the content significantly increased to 772 µg/g dwt with the increase in rainfall and decrease in air temperature in the warmer season of 2022. In most cultivars examined, capsaicin content negatively responded to the change of the climate toward higher precipitation and lower temperature except for SZ178, in which the concentration of capsaicinoids stayed insignificantly varied. The amount of vitamin C ranged between 570 and 135 µg/g dwt, with the highest content being in the BHJ and the lowest in the REK variety. In most varieties except the REK, vitamin C positively responded to a high and negatively to the reduced levels of precipitation. In conclusion, the phytochemical components of hot peppers respond differently to climatic factors—such as high rainfall, elevated air temperature, and intense sunlight—depending on the genotype’s ability to adapt to environmental changes. Full article

Human hair, commonly considered a discarded organic waste, is a keratin-rich material with remarkable potential for sustainable agriculture as an innovative resource. This study systematically explored the potential of non-composted human hair hydrolysates as eco-friendly and nutrient-rich liquid fertilizers, emphasizing their ability to enhance agricultural sustainability and mitigate organic waste accumulation. Eight distinct hydrolysates prepared with alkaline solutions were evaluated for their effects on plant growth using red-hot chili pepper (Capsicum frutescens) as the primary model under greenhouse conditions. The present study introduces a novel approach by employing an advanced digital image analysis technique to quantitatively assess 37 distinct plant growth parameters, providing an unprecedented depth of understanding regarding the impact of liquid human hair hydrolysates on plant development. Additionally, the integration of pilot-scale field trials and multi-species evaluations highlights the broader applicability and scalability of these hydrolysates as sustainable fertilizers. Collectively, these features establish this research as a pioneering contribution to sustainable agriculture and bio-waste management. The top-performing hydrolysates (KCaMgN, KMgN, KCaN) demonstrated significant enhancements in plant growth metrics, with fresh weight reaching up to 3210 mg, projected leaf area of approximately 132 cm², and crown diameter of 20.91 cm for the best-performing formulations, outperforming a commercial organomineral fertilizer by 20–46% in overall growth performance. Furthermore, observational studies on various species (such as bird of paradise flower (Strelitzia reginae), avocado (Persea americana), lemon (Citrus limon L.), Mazafati date (Phoenix dactylifera L.), and red mini conical hot pepper (Capsicum annuum var. conoides) and field trials on long sweet green peppers (Capsicum annuum) confirmed the broad applicability of these hydrolysates. Toxicity assessments using shortfin molly fish (Poecilia sphenops) validated the environmental safety of plants cultivated with hydrolysates. These findings highlight that human hair hydrolysates offer a sustainable alternative to synthetic fertilizers, contributing to waste management efforts while enhancing agricultural productivity. Full article

Studies were conducted focusing on the drying of chili pepper fruits (Capsicum annuum L.), cultivar Cyklon, using convective (AD), convective-microwave (AMD), vacuum (VD), and freeze-drying (FD) methods. The influence of the drying method and temperature on the kinetics of the process and selected quality attributes of the dried product were evaluated. It was demonstrated that the Midilli model best described the drying kinetics for all methods across the entire measurement range. FD and VD produced dried products with the highest brightness and the greatest value of the a* color parameter. The lowest b* color parameter was observed for the product dried using FD at 40 °C, while the highest b* value was noted for samples dried using AMD (100 W) at 60 °C. The highest carotenoid retention was achieved with the FD method at 40 °C, while the lowest carotenoid content was found in the product obtained using the AMD method (100 W) at 60 °C. The smallest losses of capsaicinoids were observed after FD drying at 40 °C, while the largest were found for AMD (100 W) at 60 °C. The analysis of chili pepper fruit extracts revealed the quantitative composition of 12 main phenolic compounds using the UHPLC-UV method. The highest polyphenol content was obtained with FD, while the lowest total polyphenol content was recorded after AD. Regardless of temperature, the total flavonoid content was highest in extracts from FD products, and the lowest flavonoid content was found after AMD at 100 W. For all drying methods analyzed, the total flavonoid content in the pepper extracts decreased with increasing temperature. Full article

Throughout the world, chili and chili powders are spices of considerable economic importance. Rocoto (Capsicum pubescens R. & P.) is a chili pepper used in Andean cuisine. Fresh chili is perishable and therefore it is convenient to protect the capsaicin, color and other bioactive compounds through preservation methods such as encapsulation. The present study systematically evaluates the technical and environmental aspects of producing encapsulated Rocoto red chili powder using three different wall materials—maltodextrin, rice protein and rice flour—in conjunction with two drying methods, namely convection drying and vacuum drying. Our technical objectives focused on developing an encapsulated product with high heat and vibrant red color, key attributes that significantly influence consumer purchasing behavior. In addition, the study aimed to mitigate the loss of polyphenols, flavonoids and antioxidant activity. After identifying the optimal conditions for each wall material and drying process, a comprehensive environmental assessment was conducted to identify the most efficient and sustainable production methods. The results demonstrate that rice flour encapsulation (20%) in conjunction with hot air drying (40 °C) represents the most efficacious method for the preservation of chili powder’s pungency. This approach resulted in a mere 24% reduction in Scoville units while maintaining the powder’s vibrant red coloration. This method not only preserved key bioactive compounds, including capsaicin, polyphenols and flavonoids, but also significantly enhanced the antioxidant capacity of the product. From an environmental perspective, this approach offers significant sustainability benefits, reducing the overall environmental impact by approximately 72% compared to vacuum drying of unencapsulated chili. The use of rice flour as an encapsulant aligns with sustainability goals, making it the most efficient option for balancing product quality and environmental performance. Full article

Drying extends the shelf life of crops; thus, dryers with good designs will help them dry to an optimum level. The present research work was carried out to assess and compare the performance of conventional (CD), solar tunnel (STD), and solar-cum gas-fired dryers (SGD) for drying hot chilies. The Sanam variety of hot chilies was used in this study. Samples were dried using CD, STD, and SGD methods. The drying process was conducted over three days, from 9:00 to 17:00 daily. Results showed significant differences among the drying methods in temperature, relative humidity, and moisture content reduction (p < 0.0001). The SGD consistently outperformed the other methods, achieving the highest temperature (55 °C) and lowest relative humidity (17%), compared to the STD (44 °C, 23%) and CD (34 °C, 31%). The SGD demonstrated superior efficiency, reducing moisture content from 70% to 9.36% in just 36 h, while the STD required 50 h (to 11.37%) and CD took 84 h (to 9.63%). ANOVA and post hoc analyses revealed that the SGD significantly outperformed both the STD (p = 0.0412) and CD (p = 0.0018) in moisture content reduction. Additionally, the SGD and STD better preserved the color of hot chili samples compared to CD, as determined by the Essential Oil Association (EOA) method. It is concluded that the SGD is the most technically suitable method for drying hot chilies, offering improved efficiency and quality retention. It is recommended to use an SGD for optimal results in hot pepper drying. Full article

Aflatoxin B1 (AFB1), a hepatocarcinogenic metabolite produced by certain strains of Aspergillus section Flavi, is one of the major contaminants in red chili products that affect human health. This study determined the level of AFB1 in chili traded in Oman. In addition, a survey was conducted among 260 respondents to assess consumers’ knowledge and awareness of aflatoxin contamination in chili. A competitive enzyme-linked immunosorbent assay (ELISA) was performed on 58 samples of dried red chili pods, red chili flakes, and red chili powder collected from various markets in Oman. The ELISA results showed the presence of AFB1 in all the samples analyzed. None of the dried red chili pod samples exceeded 10 ppb AFB1, the maximum permissible limit adopted by the Oman Legislation for foods, whereas a few red chili flakes and red chili powder samples exceeded 10 ppb. However, AFB1 content in all the samples was below the maximum tolerance limit of 20 ppb set by the U.S. Food and Drug Administration. The survey results revealed that most respondents were unaware of aflatoxins, as education, gender, and social media were found to be significant determinants of aflatoxin awareness. This study provides valuable insights into the level of AFB1 contamination in red chili products, raises the need for aflatoxin awareness in Oman, and urges for safe culinary practices in the region. Full article

Fermented chopped chili pepper (FCCP) is the most important fermented and processed chili pepper product, and most pepper varieties can be processed with obvious flavor differences. Many studies have tried to explain these differences using the results of component analysis, processing technology, the microbes involved, etc., but few have examined the characteristics of these varieties along with the flavor of products. We conducted a physiochemical characteristic analysis of 35 kinds of fresh chili peppers with different genotypes and made fermented products from 17 varieties, using principal component analysis (PCA) and cluster analysis (CA) to correlate their components with FCCP products. The results were as follows: (1) Protein, total acids, a* (representation of the object’s red and green color), protopectin, and fruit thickness are the five key indexes that affect the quality of fresh chili peppers the most. (2) Protein, total acids, a*, protopectin, and fruit thickness are also the key indexes that affect the quality of FCCP. (3) Suitable ranges of fresh chili pepper to manufacture FCCP are 1.3–2.0 g/100 g for protein, 2.5–4.0 g/kg for total acids, 10–15 g/100 g for protopectin, 30–39 for a*, and 1.2–2.0 mm for fruit thickness. (4) Sensory appraisal shows crispness is the most important mouthfeel sensation and can decrease during the process. The varieties with the top three scores were A12 (21G675), A13 (20Z663), and A14 (21Z698) with scores of 87.92, 74.08, and 74.15, respectively. The varieties in the top three scores are pod peppers. The PCA and CA showed that pod peppers were the most suitable materials for making FCCP. Our results will benefit others in selecting fresh chili peppers for making FCCP and provide data support for directing processable variety breeding. Full article

Objectives: This study aimed to assess postprandial blood glucose response (PBGR), relative glycemic response (RGR) and insulin response when 25 g available carbohydrates (AC) is replaced with cooked lentils in the formulation of muffins, chilies and soups. Methods: In randomized, crossover studies, healthy adults consumed foods containing 25 g AC from green lentils, red lentils or a control (wheat muffin, n = 24; rice chili, n = 24; potato soup, n = 20). Blood collected at fasting and at 15, 30, 45, 60, 90 and 120 min was analyzed to derive the incremental area under the response curve (iAUC) for glucose, insulin, RGR and maximum concentration (C_MAX). Treatment effects were assessed with repeated measures ANOVA. Results: A replacement of 25 g AC with green lentils significantly decreased glucose iAUC compared to chili and soup (p < 0.0001), but not muffin (p = 0.07) controls, while also eliciting a significantly lower insulin iAUC for all three foods (muffin p = 0.03; chili p = 0.0002; soup p < 0.0001). Red lentil foods significantly decreased glucose iAUC (muffin p = 0.02; chili p < 0.0001; soup p < 0.0001) compared to controls, with a significantly lower insulin iAUC for chili and soup (p < 0.0001) but not muffins (p = 0.09). The RGR for muffins, chilies and soups was 88, 58 and 61%, respectively, for green lentils, and 84, 48 and 49%, respectively, for red lentils. Conclusions: PBGR, insulin and RGR are decreased when lentils are incorporated into food products, providing credible evidence to promote carbohydrate replacement with lentil-based foods. Full article