Search Results (138)

Chilli pepper agroecosystems (Capsicum annuum L.) are increasingly threatened by cadmium (Cd) contamination, with emerging climatic stressors such as drought further exacerbating risks to food safety and crop productivity. This review synthesizes current evidence on microbiome-mediated Cd phytostabilisation in chilli pepper, with a particular focus on the roles of capsaicinoids and cultivar-specific genetic regulation in shaping rhizosphere microbial communities. Existing studies demonstrate that capsaicinoid-rich cultivars selectively recruit specialized rhizosphere microbes, enhancing root-level Cd sequestration and achieving Cd retention efficiencies of approximately 40–55%, thereby substantially restricting Cd translocation to edible fruit tissues. Multi-strain plant growth-promoting rhizobacteria (PGPR) consortia, especially when combined with structured organic amendments, have been reported to reduce fruit Cd and nickel (Ni) accumulation by more than 87% in contaminated soils. These responses are regulated by pungency-associated genetic loci, including Pun1 (pungency locus 1) and Pun4 (pungency locus 4) genes, which influence secondary metabolism and microbial assembly under metal stress conditions. The review highlights key knowledge gaps regarding the long-term stability of engineered rhizobiomes, the in situ dynamics of the Capsicum volatilome as a microbial recruitment signal, and the interactive effects of Cd contamination and drought in field environments. Overall, this synthesis provides a mechanistic framework for deploying high-pungency cultivars and microbiome-based strategies to improve Cd phytostabilisation, with important implications for sustainable chilli production in drought-prone, metal-contaminated agroecosystems. Full article

The Habanero pepper (Capsicum chinense Jacq.) is the main crop of the Yucatán Peninsula and is recognized and distinguished from other Habanero peppers cultivated elsewhere in the world due to its aroma, flavor, and high pungency, which is conferred by a group of compounds called capsaicinoids. These compounds are in high demand by various industries due to their antioxidant, anti-inflammatory, analgesic, and antimicrobial properties. The present study aimed to quantify capsaicin and dihydrocapsaicin contents in 29 Habanero pepper hybrids cultivated under greenhouse conditions in Yucatán and to evaluate their pungency potential. Capsaicinoids were extracted from mature fruits using acetonitrile and quantified by HPLC with fluorescence detection (HPLC-FLD). Capsaicin concentrations ranged from 19.95 to 73.55 mg g⁻¹ dry weight (DW), while dihydrocapsaicin varied from 4.57 to 14.36 mg g⁻¹ DW. Total capsaicinoid content differed significantly among hybrids, ranging from 27.33 to 85.05 mg g⁻¹ DW, corresponding to pungency levels between 439,979 and 1,369,360 Scoville Heat Units (SHU). Hybrids H14, H15, and H3 exhibited exceptionally high pungency, exceeding 1.1 × 10⁶ SHU. The wide variability observed under uniform growing conditions indicates pronounced genotype-dependent differences in capsaicinoid accumulation and identifies promising hybrid materials for breeding programs and agro-industrial applications requiring elevated capsaicinoid content. Full article

Drying chili peppers is a crucial technique for their preservation, as it extends shelf life while minimizing the degradation of high-value bioactive compounds. This study evaluated the impact of modulated solar irradiation on the drying kinetics and quality retention of “Chile de Agua” (Capsicum annuum L.) peppers across three maturity stages (unripe, ripe, and overripe). Two cylindrical solar dryers were employed: a conventional solar dryer (CSD) and a novel Solar Dryer with Dynamic Irradiance Control (SDIC) utilizing Polymer Dispersed Liquid Crystal (PDLC) technology. Drying behavior was analyzed through moisture ratio and drying rate, while quality attributes were assessed via color parameters, capsaicinoid content, and flavonoid profiling using UPLC-PDA-ESI-MS. Results demonstrated that the maturity stage significantly influences drying kinetics; unripe fruits exhibited the fastest dehydration rate, reducing drying time by approximately 14% compared to overripe fruits. Regarding quality, the CSD better preserved color (ΔE of 15.29 for ripe chilies). At the same time, the SDIC system significantly favored the retention of bioactive compounds, maintaining higher concentrations of total capsaicinoids (up to 1700 µg/g DW) and flavonoids such as luteolin (15.9 mg/100 g DW) and quercitrin (11.5 mg/100 g DW), especially in ripe fruits. The findings suggest that optimal processing requires selecting the drying method based on the targeted final use: CSD for color preservation in unripe chilies, or SDIC for maximizing bioactive retention in ripe fruits. Full article

Background/Objectives: The quality of dried chili peppers is critically influenced by geographical origin, yet the metabolic basis for these differences remains insufficiently explored. This study sought to elucidate the region-specific metabolic profiles and their association with key quality traits in the pepper cultivar ‘Hong Guan 6’. Methods: Fruits harvested from three major cultivation regions in China were analyzed. We quantified fat and capsaicinoid content and employed an integrated LC-MS and GC-MS untargeted metabolomics approach to characterize the metabolite composition. Multivariate statistical analyses were applied to identify differentially abundant metabolites (DAMs) and uncover their related biochemical pathways. Results: Significant regional variations in fat and capsaicinoid content were observed, with peppers from Pengzhou (PZ) exhibiting the highest capsaicin levels. Metabolomic profiling revealed 529 metabolites that were significantly more abundant in PZ samples. These metabolites were enriched in several key pathways, including beta-alanine metabolism, plant hormone signal transduction, and N-glycan biosynthesis. Specifically, elevated levels of β-alanine and malonate in the beta-alanine metabolism pathway were detected in PZ and Anyue (AY) samples, suggesting a potential biochemical mechanism for their enhanced fat synthesis. Conclusions: Our findings demonstrate that geographical origin significantly reprograms the pepper metabolome, directly impacting quality attributes. The results provide crucial insights into the biochemical mechanisms, particularly those involving beta-alanine metabolism, that underpin the differences in critical quality traits such as fat content. Full article

This study investigated the effects of encapsulated capsaicinoids (CAPs), containing 0.47% capsaicin and 0.22% dihydrocapsaicin, on growth, serum parameters, nutrient digestibility, and intestinal health in weaned piglets. A total of 168 piglets were randomly assigned to four groups: a basal diet or the same diet supplemented with 200 (LDC), 400 (MDC), or 600 (HDC) mg/kg of CAPs. The results indicated that CAPs improved lipid metabolism, evidenced by higher crude fat digestibility in the LDC and MDC groups and reduced serum low-density lipoprotein cholesterol in all CAP groups compared to the control. Glutathione peroxidase activity was significantly higher in the MDC and HDC groups. Histological analysis showed reduced hepatic vacuolation, enlarged fungiform papillae with shallower taste pores in the tongue epithelium, and deeper ileal crypts in the LDC group. At the molecular level, ZO-1 expression in the ileum was significantly upregulated in LDC piglets. Colonic microbiota analysis revealed decreased relative abundances of Lachnospiraceae_AC2044_group, Lachnospiraceae_XPB1014_group, and Rikenellaceae_RC9_gut, while Butyricicoccus was significantly enriched in the LDC group. In conclusion, CAPs supplementation enhanced fat digestibility, lipid metabolism, antioxidant capacity, intestinal development, and colonic microbiota composition, with the 200 mg/kg dose showing the most pronounced effects. Full article

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