•Efficient extraction method was standardized for capsaicinoid quantification.•Capsaicinoids quantified in three fruit maturity stages and ripened red fruit exhibited highest.•Capsaicinoid found ...highest in placenta compare to other fruit components.•Capsaicinoid content in 15 dried Naga king chilli land races were quantified.•Amino acid and fatty acid composition analysed in fruit components and whole fruit.
The world hottest Naga king chilli is cultivated and consumed in Northeast India. Capsaicinoids, amino acids and fatty acids were studied in fruit and fruit components of Naga king chilli. Capsaicinoid content was increased in each ripening stage and maximum level was observed at red color fruits. Total protein and fat content of placenta was 19.41 and 20.36% respectively. Capsaicinoids of placenta (7.35±2.241%) was higher followed by seed (3.83±1.358%) and pericarp (2.91±0.667%). Similarly, essential amino acid content was also higher in placenta compared to other components. Amino acid score ranged from 37 to 38 with cystine and methionine as limiting amino acid. Low level of palmitic, stearic and α-linolenic acid and very high level of linoleic acid were found in seeds. Total polyunsaturates of seeds were higher followed by whole fruit. Naga king chilli is unique due to its high capsaicinoid content and it offers potential crop for the future exploitation.
Several aflatoxin inhibitors can modulate the antioxidant system in fungi. In this work, the effect of the ethanolic extract of Capsicum chinense and Piper nigrum fruits, capsaicin, and piperine on ...the expression of the aflE, aflG, aflH, aflI, aflK, aflL, aflO, aflP, and aflQ genes involved in the aflatoxin biosynthetic pathway in Aspergillus parasiticus were studied by qRT-PCR analysis. As well as, the effect on the expression of fungal antioxidant genes (sod1, catA, and cat2) and enzymatic activity of catalase (CAT) and superoxide dismutase (SOD). Results reveal that the highest (p < 0.05) radial growth inhibition (68 and 86%) and aflatoxins production inhibition (73 and 80%) was observed with capsaicin and piperine respectively, at 300 µg/mL, instead of the ethanolic extract at the same concentration. The qRT-PCR analysis showed that compounds and extracts at 300 µg/mL induced a down-regulation of aflatoxin genes and an up-regulation on the fungal antioxidant genes. CAT activity increased by 23.15, 36.65, 51.40, and 65.50%, in the presence of C. chinense and P. nigrum extract, capsaicin, and piperine exposure, respectively. While SOD activity was not significantly impacted (p > 0.05). In conclusion, the capsaicin and piperine, two antifungal and anti-aflatoxigenic compounds produce an up-regulation of antioxidant defense genes accompanied by an enhancement of catalase enzymatic activity in A. parasiticus.
Bacterial, fungal, and parasitic infections increase morbimortality rates and hospital costs. This study aimed to assess the antimicrobial and antiparasitic activities of the crude extract from the ...seeds and peel of the pepper Capsicum chinense Jacq. and of the isolated compound capsaicin and to evaluate their ability to inhibit biofilm formation, eradicate biofilm, and reduce hemolysin production by Candida species. The crude ethanolic and hexane extracts were obtained by maceration at room temperature, and their chemical compositions were analyzed by liquid chromatography coupled to mass spectrometry (LC–MS). The antimicrobial activity of the samples was evaluated by determining the minimum inhibitory concentration. Inhibition of biofilm formation and biofilm eradication by the samples were evaluated based on biomass and cell viability. Reduction of Candida spp. hemolytic activity by the samples was determined on sheep blood agar plates. The antiparasitic action of the samples was evaluated by determining their ability to inhibit Toxoplasma gondii intracellular proliferation. LC–MS-ESI analyses helped to identify organic and phenolic acids, flavonoids, capsaicinoids, and fatty acids in the ethanolic extracts, as well as capsaicinoids and fatty acids in the hexane extracts. Antifungal action was more evident against C. glabrata and C. tropicalis. The samples inhibited biofilm formation and eradicated the biofilm formed by C. tropicalis more effectively. Sub-inhibitory concentrations of the samples significantly reduced the C. glabrata and C. tropicalis hemolytic activity. The samples only altered host cell viability when tested at higher concentrations; however, at non-toxic concentrations, they reduced T. gondii growth. In association with gold standard drugs used to treat toxoplasmosis, capsaicin improved their antiparasitic activity. These results are unprecedented and encouraging, indicating the Capsicum chinense Jacq. peel and seed extracts and capsaicin display antifungal and antiparasitic activities.
► Native carotenoids composition in 12 different cultivars of chilli peppers. ► HPLC-DAD-APCI-MS methodology. ► “Healthy” carotenoids were detected in the various cultivars investigated. ► Specific ...carotenoid profile in different cultivars of the same species. ► Pungency levels determined.
In this research 12 different varieties of Capsicum cultivars belonging to three species (Capsicum chinense, Capsicum annuum, Capsicum frutescens) and of various colour, shape, and dimension have been characterised by their carotenoids and capsaicinoids content. The berries were cultivated in the region Emilia-Romagna, in Northern Italy. The native carotenoid composition was directly investigated by an HPLC-DAD-APCI-MS methodology, for the first time. In total, 52 carotenoids have been identified and considerable variation in carotenoid composition was observed among the various cultivars investigated. Among the cultivars with red colour, some Habanero, Naga morich and Sinpezon showed an high β-carotene content, whereas Serrano, Tabasco and Jalapeno showed an high capsanthin content and the absence of β-carotene. Habanero golden and Scotch Bonnet showed a high lutein, α-carotene and β-carotene amounts, and Habanero orange was rich in antheraxanthin, capsanthin and zeaxanthin. Cis-cryptocapsin was present in high amount in Habanero chocolate.
The qualitative and quantitative determination of the capsaicinoids, alkaloids responsible for the pungency level, has also been estimated by a validated chromatographic procedure (HPLC-DAD) after a preliminary drying step and an opportune extraction procedure. Results have also been expressed in Scoville units. Dry matter and water activity have also been established on the fresh berries. The dried peppers of each variety were then submitted to the evaluation of the total nitrogen content, measured by a Dumas system, permitting to provide information on the protein content that was found to be in the range between 7 and 16%.
Resistance conferred by the L super(3) gene is active against most of the tobamoviruses, including the Spanish strain (PMMoV-S), a P sub(1,2) pathotype, but not against certain strains of pepper mild ...mottle virus (PMMoV), termed P sub(1,2,3) pathotype, such as the Italian strain (PMMoV-I). Both viruses are nearly identical at their nucleotide sequence level (98%) and were used to challenge Capsicum chinense PI159236 plants harbouring the L super(3) gene in order to carry out a comparative proteomic analysis of PR proteins induced in this host in response to infection by either PMMoV-S or PMMoV-I. PMMoV-S induces a hypersensitive reaction (HR) in C. chinense PI159236 plant leaves with the formation of necrotic local lesions and restriction of the virus at the primary infection sites. In this paper, C. chinense PR protein isoforms belonging to the PR-1, beta -1,3-glucanases (PR-2), chitinases (PR-3), osmotin-like protein (PR-5), peroxidases (PR-9), germin-like protein (PR-16), and PRp27 (PR-17) have been identified. Three of these PR protein isoforms were specifically induced during PMMoV-S-activation of C. chinense L super(3) gene-mediated resistance: an acidic beta -1,3-glucanase isoform (PR-2) (M sub(r) 44.6; pI 5.1), an osmotin-like protein (PR-5) (M sub(r) 26.8; pI 7.5), and a basic PR-1 protein isoform (M sub(r) 18; pI 9.4-10.0). In addition, evidence is presented for a differential accumulation of C. chinense PR proteins and mRNAs in the compatible (PMMoV-I)-C. chinense and incompatible (PMMoV-S)-C. chinense interactions for proteins belonging to all PR proteins detected. Except for an acidic chitinase (PR-3) (M sub(r) 30.2; pI 5.0), an earlier and higher accumulation of PR proteins and mRNAs was detected in plants associated with HR induction. Furthermore, the accumulation rates of PR proteins and mRNA did not correlate with maximal accumulation levels of viral RNA, thus indicating that PR protein expression may reflect the physiological status of the plant.
•Placenta’s capsaicin is connected with fluctuation in metabolism during fruit ripening.•Metabolite levels in both placenta and pericarp are uniformly stable across accessions during fruit ...development.•Accumulation of capsaicinoids in placenta tissues do not largely affect the levels of primary metabolites.
Fruit pungency is caused by the accumulation of capsaicinoids, secondary metabolites whose relation to primary metabolism remains unclear. We have selected ten geographically diverse accessions of Capsicum chinense Jacq with different pungency levels. A detailed metabolic profile was conducted in the fruit placenta and pericarp at 20, 45, and 60 days after anthesis aiming at increasing our understanding of the metabolic changes in these tissues across fruit development and their potential connection to capsaicin metabolism. Overall, despite the variation in fruit pungency among the ten accessions, the composition and metabolite levels in both placenta and pericarp were uniformly stable across accessions. Most of the metabolite variability occurred between the fruit developmental stages rather than among the accessions. Interestingly, different metabolite adjustments in the placenta were observed among pungent and non-pungent accessions, which seem to be related to differences in the genetic background. Furthermore, we observed high coordination between metabolites and capsaicin production in C. chinense fruits, suggesting that pungency in placenta is adjusted with primary metabolism.
•Chili pepper increased fallen leaves weight and decreased leaf area as responses to dry and waterlogged soil conditions.•Leaf chlorophyll content on chili pepper increased and their chlorophyll a/b ...ratio decreased in dry and water logged soil conditions.•Chlorophyll a/b ratio is available to evaluate stress level by soil water, vapor pressure deficit and solar radiation.•A regression model for estimating shoot dry weight (SDW) from plant height (PH) and SPAD value (SPAD) was developed. The model (SDW = 0.131 PH + 0.047SPAD − 2.408, R2adj = 0.836).
Flood and drought have been increasing due to global climate changes and these extreme water-related events often affect crop productions globally. This study aims to develop a growth simulation model that correspond to sequential soil water status by revealing morph-physiological related responses on the chili pepper (Capsicum spp.). Two experiments were conducted in a greenhouse and nine treatments were established between dry and waterlogged soil conditions by using a slope field with sand. Results showed leaf water potential and stomatal conductance decreased with increasing soil water stress level. On the other hand, chili pepper increased total chlorophyll content and decreased chlorophyll a/b ratio to compensate the redaction of the leaf area as a response to soil water stress. Moreover, high air vapor pressure deficit and solar radiation condition influenced their morph-physiological traits as environmental stress coupled with soil water stress. A multiple regression model for estimating shoot dry weight (SDW) using plant height (PH) and soil plant analysis development (SPAD) was developed (SDW = 0.131 PH + 0.047SPAD − 2.408). It showed a high coefficient of determination (R2adj = 0.836). This model is certainly useful for estimating SDW under wide range soil water statuses and vapor pressure deficit conditions.
A case where a diptilomiopid eriophyoid mite kills its host plant is reported. Rhynacus acerioides Flechtmann, 2014 is recorded by first time in Brazil. A key to species of the genus is provided.
Pepper is renowned worldwide for its distinctive spicy flavor. While the gene expression characteristics of the capsaicinoid biosynthesis pathway have been extensively studied, there are already a ...few reports regarding transcriptional regulation in capsaicin biosynthesis. In this study, 73
were identified in the genome of
, and their physicochemical traits, DNA, and protein sequence characteristics were found to be complex. Combining RNA-seq and qRT-PCR data, the
transcription factor
, which was associated with the accumulation tendency of capsaicinoid, was screened and named
.
was highly expressed in the placenta of spicy peppers. The heterologous expression of
in
promoted the expression of genes
,
,
,
,
, and
and led to the accumulation of lignin and flavonoids. Furthermore, the expression of the capsaicinoid biosynthesis pathway genes (CBGs)
,
, and
was significantly reduced in
-silenced pepper plants, resulting in a decrease in the amount of capsaicin. However, there was no noticeable difference in lignin accumulation. The findings suggested that
could be involved in regulating capsaicinoid synthesis by promoting the expression of genes upstream of the phenylpropanoid pathway and inhibiting CBGs' expression. Moreover, the results highlighted the role of
in controlling the pungency of pepper and suggested that the competitive relationship between lignin and capsaicin could also regulate the spiciness of the pepper.
Summary
Capsaicinoids are unique compounds that give chili pepper fruits their pungent taste. Capsaicinoid levels vary widely among pungent cultivars, which range from low pungency to extremely ...pungent. However, the molecular mechanisms underlying this quantitative variation have not been elucidated. Our previous study identified various loss‐of‐function alleles of the pAMT gene which led to low pungency. The mutations in these alleles are commonly defined by Tcc transposon insertion and its footprint. In this study, we identified two leaky pamt alleles (pamtL1 and pamtL2) with different levels of putative aminotransferase (pAMT) activity. Notably, both alleles had a Tcc transposon insertion in intron 3, but the locations of the insertions within the intron were different. Genetic analysis revealed that pamtL1, pamtL2 and a loss‐of‐function pamt allele reduced capsaicinoid levels to about 50%, 10% and less than 1%, respectively. pamtL1 and pamtL2 encoded functional pAMT proteins, but they exhibited lower transcript levels than the functional type. RNA sequencing analysis showed that intronic transposons disrupted splicing in intron 3, which resulted in simultaneous expression of functional pAMT mRNA and non‐functional splice variants containing partial sequences of Tcc. The non‐functional splice variants were more dominant in pamtL2 than in pamtL1. This suggested that the difference in position of the intronic transposons could alter splicing efficiency, leading to different pAMT activities and reducing capsaicinoid content to different levels. Our results provide a striking example of allelic variations caused by intronic transposons; these variations contribute to quantitative differences in secondary metabolite contents.
Significance Statement
This study demonstrated that differences in the position of an intronic transposon can determine variation in the content of secondary metabolites. The two leaky pamt alleles identified here can provide insights into the domestication process of chili peppers and may also offer a breeding tool for the quantitative reduction of pungency.
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