Search Results (133)

Capsicum pubescens (rocoto) is an Andean domesticate with notable agronomic and nutraceutical potential, yet it remains underrepresented in chili pepper breeding programs. In this study, 78 accessions from the Peruvian Andes were evaluated in a single field environment during the 2024 growing season for 28 variables spanning plant architecture, phenology and yield, color (CIELAB), weight, fruit morphology, physicochemical variables, and functional phytochemicals, including total phenolics, carotenoids, ascorbic acid, capsaicinoids, and antioxidant activity (FRAP, DPPH, ABTS). Descriptive analyses revealed broad phenotypic diversity in key variables such as yield and bioactive compounds. Spearman correlations uncovered a clear modular structure, with strong within-domain associations across morphological, chromatic, and biochemical variables, and statistically significant but low-magnitude cross-domain associations (e.g., fruit length with pungency, redness with total phenolics). Principal component analysis and hierarchical clustering resolved three differentiated phenotypic profiles: (i) low-pungency accessions with high soluble solids and varied fruit colors; (ii) highly pungent materials with elevated antioxidant capacity; and (iii) large, red-fruited accessions with considerable carotenoid content and high moisture. This multivariate architecture revealed weak cross-block correlations among agronomic, color, and functional traits, enabling selection of promising accessions combining desirable agronomic attributes and favorable bioactive profiles in specific accessions. These results provide a quantitative foundation for future breeding strategies in C. pubescens, opening concrete opportunities to develop improved cultivars that simultaneously meet productivity and functional quality criteria. Full article

Capsaicin, a naturally occurring polyphenol, is known to affect energy expenditure and muscle fatigue and modulate contractions in skeletal muscle. The L-type Ca²⁺ channels are known to be an important ion channel involved in the various muscle functions and the effect of capsaicin on the skeletal L-type Ca²⁺ channels is currently unknown. In this study, the effects of capsaicin and capsaicin analogs on depolarization-induced Ca²⁺ effluxes through L-type Ca²⁺ channels in transverse tubule membranes from rabbit skeletal muscle and L-type Ca²⁺ currents recorded using the whole-cell patch clamp technique in rat myotubes were examined. Capsaicin, in the concentration range of 3–100 µM, inhibited depolarization-induced Ca²⁺ effluxes. The effect of capsaicin was not reversed by TRPV1 antagonist SB-366791 (10 µM). While vanilloids (30 µM) including vanillin, vanillyl alcohol, and vanillylamine were ineffective, other capsaicinoids (30 µM) including dihydrocapsaicin, nonivamide, and nordihydrocapsaicin significantly inhibited Ca²⁺ effluxes, suggesting that hydrocarbon chains are required for inhibition. In rat myotubes, capsaicin inhibited L-type Ca²⁺ currents with an IC₅₀ value of 27.2 μM in the presence of SB-366791. Furthermore, in docking studies and molecular dynamic simulations, capsaicinoids with an aliphatic tail showed stronger binding and stable bent conformations in CaV1.1, forming hydrogen bonds with Ser1011 and Thr935 and hydrophobic/π–alkyl contacts with Phe1008, Ile1052, Met1366, and Ala1369, resembling the binding mode of amlodipine. In conclusion, the results indicate that the function of L-type Ca²⁺ channels in mammalian skeletal muscle was inhibited by capsaicin and capsaicin analogs in a TRPV1-independent manner. Full article

The bHLH transcription factors play a crucial regulatory role in plant growth and development. In this study, the CcbHLH68 gene was cloned from the pepper cultivar ‘Shuanla’. Subsequent bioinformatics analysis, subcellular localization, expression pattern profiling, along with yeast one-hybrid and dual-luciferase reporter assays, were conducted to preliminarily elucidate its regulatory mechanism in capsaicinoid biosynthesis. The results revealed that the visualization of upstream cis-elements of CcbHLH68 suggests its potential regulation by hormones. Furthermore, subcellular localization experiments confirmed that the CcbHLH68 protein is localized in the nucleus. Expression analysis of CcbHLH68 across different tissues by qRT-PCR identified its predominant expression in the placenta at 30 days post-anthesis. Further experimental evidence from both gene silencing and transient overexpression assays demonstrated a positive correlation between CcbHLH68 and the expression of multiple capsaicinoid biosynthetic genes. When it was silenced or transiently overexpressed, the content of capsaicinoids decreased by 40.9% or increased by 113.7%, respectively. Yeast one-hybrid and dual-luciferase reporter assays confirmed that CcbHLH68 can directly bind to the CcCOMT promoter and activate its transcription. In summary, this study preliminarily reveals the molecular mechanism by which CcbHLH68 participates in capsaicinoid biosynthesis through regulating the expression of key genes in the biosynthetic pathway, thereby providing a theoretical foundation for enhancing capsaicinoid content via molecular breeding. Full article

For centuries, people have used herbs, plants, and spices as remedies for health problems or simply to ameliorate body energy or vitality because of the bioactive compounds they contain. The Capsicum genus, which includes the chili pepper, is one of the oldest crops to be domesticated and used. It is characterized by three qualities: pungency/flavor, color, and aroma. Capsaicinoids are responsible for the pungent flavor. Carotenoids and flavonoids determine the remarkable and colorful tones of chili peppers. Volatile compounds provide their characteristic aroma. This prompts consumers to purchase and utilize the numerous varieties of chili peppers, whether fresh or dried. The presence of these bioactive compounds gives chili peppers functional attributes that promote health. This paper reviews the scientific research carried out over the last 25 years on these attributes. This paper also looks at how Capsicum fruits could be used as a valuable source of nutrients from plants that have beneficial biological properties. Full article

Capsaicinoids (CPCs) are regarded as a typical marker of waste oil, which has emerged as a serious food safety issue in developing countries, necessitating the development of rapid, sensitive, and specific detection methods. In this study, a novel hapten was synthesized to generate a high-affinity monoclonal antibody (mAb) targeting CPCs. Subsequently, aggregation-induced emission fluorescent microspheres (AIEFMs), known for their superior fluorescence intensity, were utilized as an enhanced probe to develop a lateral flow immunoassay (LFIA) based on mAb 8B4 for CPC detection. For comparison, a traditional gold nanoparticle (AuNP)-LFIA was also constructed using the corresponding mAb. The AIEFM-LFIA demonstrated a limit of detection (LOD) of 0.33 µg/kg for CPCs in edible oil samples, which is 4.21 times lower than the LOD of 1.39 µg/kg achieved by the AuNP-LFIA. And the assay effectively identified three additional CPCs, with LODs ranging from 0.26 to 0.99 µg/kg, while exhibiting minimal cross-reactivity with CPC analogs, indicating high specificity. The recovery rates of the AIEFM-LFIA in oil samples ranged from 75.0% to 106.0%, with coefficients of variation ≤ 8.3%, exhibiting excellent accuracy and precision. Furthermore, the results of the AIEFM-LFIA demonstrated a strong degree of correlation with liquid chromatography–tandem mass spectrometry, with a correlation coefficient (R²) of 0.978. Consequently, the developed AIEFM-LFIA shows significant promise as a rapid, sensitive, specific, and reliable method for detecting CPCs in oil samples. Full article

Capsicum is one of the most economically significant vegetable crops worldwide, owing to its high content of bioactive compounds with nutritional, pharmacological, and industrial relevance. However, research has focused on C. annuum, often disregarding local diversity and secondary gene pools, which may contain hidden variation for quality traits. Therefore, this study evaluated the genetic and phenotypic diversity of 283 accessions from the Colombian germplasm collection in the agrobiodiversity hotspot of northwest South America, representing all five domesticated species of the genus. A total of 18 morphological, physicochemical, and biochemical fruit traits were assessed, including texture, color, capsaicinoid, and carotenoid content. The phenotypic data were integrated with genomic information obtained through genotyping-by-sequencing (GBS) using the C. annuum reference genome and a multispecies pangenome. Fixed-and-Random-Model-Circulating-Probability-Unification (FarmCPU) and Bayesian-information-and-Linkage-disequilibrium-Iteratively-Nested-Keyway (BLINK) genome-wide association studies (GWAS) were performed on both alignments, respectively, leading to the identification of complex polygenic architectures with 144 and 150 single nucleotide polymorphisms (SNPs) significantly associated with key fruit quality traits. Candidate genes involved in capsaicinoid biosynthesis were identified within associated genomic regions, terpenoid and sterol pathways, and cell wall modifiers. These findings highlight the potential of integrating pangenomic resources with multi-omics approaches to accelerate Capsicum improvement programs and facilitate the development of cultivars with enhanced quality traits and increased agro-industrial value. Full article

Efficient irrigation management is essential for optimizing yield and quality in specialty crops like hot peppers (Capsicum chinense), particularly under controlled greenhouse environments. This study employed a novel sensor-based system integrating soil moisture and sap flux monitoring to evaluate water use dynamics in Capsicum chinense, a species for which such applications have not been widely reported. Three cultivars—Habanero, Helios, and Lantern—were grown under three volumetric soil moisture contents: low (15%), medium (18%), and high (21%). Water uptake was measured at leaf (transpiration, stomatal conductance) and plant levels (sap flux via heat balance sensors). Photosynthesis, fruit yield, and capsaicinoid concentrations were assessed. Compared to high irrigation, medium and low irrigation increased photosynthesis by 16.6% and 22.2%, respectively, whereas high irrigation favored greater sap flux and vegetative growth. Helios exhibited an approximately 8.5% higher sap flux as compared to Habanero and about 10% higher as compared to Lantern. Helios produced over 30% higher fruits than Habanero and Lantern under high irrigation. Habanero recorded the highest pungency, with a capsaicinoid level of 187,292 SHU—exceeding Lantern and Helios by 56% and 76%, respectively. Similarly, nordihydrocapsaicin and dihydrocapsaicin accumulation were more cultivar-dependent than irrigation-dependent. No significant interaction between cultivar and irrigation was observed, indicating genotype-driven water use strategies. Our study contributes to precision horticulture by integrating soil moisture and sap flux sensors to reveal cultivar-specific water use strategies in Capsicum chinense, thereby demonstrating the potential of an integrated sensor-based irrigation system for efficient irrigation management under increasing water scarcity in protected environments. As a preliminary greenhouse study aimed at maintaining consistent irrigation throughout the growing season across three volumetric soil moisture levels, these findings provide a foundation for subsequent validation and exploration under diverse soil moisture conditions including variations in stress duration, stress frequency, and stress application at different phenological stages. Full article

This study investigated the effects of dietary capsaicinoid (CAP) supplementation on broiler chickens subjected to an inflammatory challenge induced by lipopolysaccharide (LPS). A total of 144 Cobb500™ male broilers (Rivelli Alimentos SA, Matheus Leme, Brazil), raised from 1 to 21 days, were randomly assigned to three treatments, with eight replicates of six birds. Treatments were a control diet (CON), a control diet with LPS administration (CON+LPS), and a control diet supplemented with 1 mg CAP/kg feed and LPS (CAP+LPS). LPS was administered intraperitoneally on days 14, 16, 18, and 20. Performance, intestinal morphometry, serum metabolites, and jejunal gene expression related to oxidative and inflammatory responses were evaluated. Slaughter was at 20 days. Data were subjected to ANOVA and means compared by Tukey’s test at 0.05 significance. CON broilers exhibited the highest feed intake and a better feed conversion ratio (p < 0.05) compared to CON+LPS. CAP+LPS broilers showed higher body weight gain than CON+LPS but lower than CON broilers (p < 0.001). CON+LPS broilers had the highest crypt depth (p = 0.002). Higher mRNA expression of superoxide dismutase and catalase (p > 0.05) was observed in CON broilers. In conclusion, supplementation with a 1 mg CAP/kg diet improves the growth performance and intestinal morphometry of LPS-challenged broiler chickens. 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 Capsicum genus, native to the Americas and cultivated worldwide for culinary and medicinal purposes, includes five domesticated species with diverse fruit characteristics, pungency, and phytochemical profiles. However, the influence of casual urban backyard growing conditions on these traits remains unknown. In this study, we first assessed morphological production traits of 11 popular pepper cultivars over two growing seasons to establish a consistent baseline for cultivar performance. Next, we evaluated capsaicinoid and phenolic profiles of 47 pepper cultivars, which contribute to their pungency and antioxidant properties. Capsaicinoid profiles revealed species-specific ratios of capsaicin, dihydrocapsaicin, and nordihydrocapsaicin, with C. annuum and C. baccatum displaying an average 64:30:6 profile, C. chinense and C. frutescens showing a capsaicin-dominant 73:25:2 profile, and C. pubescens expressing a distinct dihydrocapsaicin-dominant 34:60:6 profile. Antioxidant activity positively correlated with capsaicinoid content (ABTS: R² = 0.8264, p < 0.0001; FRAP: R² = 0.8117, p < 0.0001), with C. chinense (Carolina Reaper) exhibiting the highest activity (FRAP = 111.8 µM TE/g). In LPS-activated macrophages, all cultivars suppressed nitric oxide production both at the enzymatic (66–89%, p < 0.001) and gene expression levels (4.2 to 5.3-fold reduction, p < 0.05). Interleukin IL-1β expression was upregulated (3.8 to 12.9-fold, p < 0.001), while no significant effects were noted on Cox-2, IL-6, and MCP-1 mRNA levels. These results provide novel insights into the molecular and biochemical adaptations of peppers grown in urban environments and underscore the importance of optimizing cultivation conditions to maximize their bioactive potential and health benefits. 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

Nanomaterials (NMs) hold significant potential for enhancing agricultural production, extending the shelf life, and maintaining the quality of postharvest vegetables and fruits. In this study, after foliar spraying with 1, 10, and 50 mg of L⁻¹ Fe-P NMs at different stages (seedling, flowering, and fruit stage), the pepper plant growth was significantly improved. In particular, the foliar application of 10 mg of L⁻¹ Fe-P NMs during the flowering stage was found to be an optimal cultivation approach to promote the growth, yield, and freshness of peppers. Compared with the control group, Fe-P NMs increased net photosynthetic rate, plant height, and fruit number by 132.7%, 40.4%, and 265.7%, respectively. The applied Fe-P NMs, at the flowering stage, altered the capsaicin metabolic pathway, upregulating the genes for the synthesis of total phenols, flavonoids, lignans, and capsaicinoids. Consequently, these metabolites, which are beneficial for maintaining the freshness of pepper fruits, were increased. Furthermore, Fe-P NMs at the flowering stage downregulated the abundance of rot-causing microorganisms (Enterobacter and Chryseobacterium) and upregulated beneficial microorganisms (Pseudomonas, Arthrobacter, Sphingobacterium, and Paenibacillus) to change the microbial community structure. This ultimately created a micro-ecological environment conducive to the preservation of pepper fruits. For comparison, during pepper fruit storage, dipping and spraying with Fe-P NM suspensions effectively delayed weight loss and enhanced the growth of beneficial bacteria. Nevertheless, the effect was less pronounced than preharvest foliar application. This study provides insights into the pre- or postharvest application of NMs for improving the preservation performance of pepper fruits. Full article

Capsaicinoids obtained from lyophilized serrano chili by sorbitan monooleate solutions were investigated. Sorbitan monooleate was as effective as methanol in extracting capsaicin and dihydrocapsaicin (DHC). Subsequently, a Box–Behnken design was used to optimize capsaicin, DHC, and polyphenol extraction, as well as to evaluate the antioxidant capacity of dehydrated serrano chili. Particle size (PS) (20–60 mesh), processing temperature (55–75 °C), and sorbitan concentration (1.5–2.5%) were selected as independent variables. The statistical analysis showed that the quadratic models adequately describe the response of the concentration of capsaicin and DHC, but not with polyphenols and antioxidant capacity. The highest extraction of capsaicin (~620 mg/100 g dw) and DHC (~520 mg/100 g dw) was achieved with the combination of sorbitan at 2%, temperature at 65 °C, and PS from 40 mesh. Experimental and predicted values were closely consistent. Meanwhile, extracts with the highest antioxidant potential (~7510 and ~5820 µM of Trolox Eq/100 g dw for ABTS and FRAP, respectively) were those extracted in sorbitan and PS from 40 mesh. In contrast, the highest values of polyphenols (~171 mg gallic acid Eq/100 g dw) were found in the extracts prepared at 75 °C. These results suggest that sorbitan monooleate solutions can be an effective, non-toxic, and environmentally responsible way to obtain capsaicinoids and bioactive compounds from dehydrated serrano chili. 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

Capsaicinoids, the key compounds responsible for pepper pungency, have significant commercial and health value, yet the role of endophytic bacteria in their biosynthesis remains unclear. This study investigated the relationship between endophytic bacterial communities and capsaicinoid content across 100 Capsicum annuum varieties. Two high-capsaicinoid (35.0 and 24.8 mg/g) and two low-capsaicinoid (0.8 and 0.9 mg/g) varieties were selected for 16S rRNA sequencing and microbial analysis. High-capsaicinoid varieties exhibited greater bacterial richness and diversity compared to low-capsaicinoid varieties. Taxonomic profiling revealed distinct community compositions: Enterobacter, Bacteroides, and Escherichia_Shigella were enriched in high-capsaicinoid fruits and positively correlated with capsaicinoid levels, while Chujaibacter and Brochothrix dominated the low-capsaicinoid varieties. Functional annotation highlighted nitrogen-fixing bacteria as more abundant in high-capsaicinoid varieties. Inoculating peppers with isolated Enterobacter strains significantly increased capsaicinoid content, confirming its role in biosynthesis. These findings demonstrate that the pepper genotype shapes endophytic bacterial communities, which in turn influence capsaicinoid production through metabolic- and nitrogen-associated pathways. This study provides foundational insights into microbiome-mediated enhancement of pepper pungency, offering potential strategies for agricultural and industrial applications. Full article