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Christopher A Reilly - One of the best experts on this subject based on the ideXlab platform.
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Capsaicinoid metabolism by the generalist helicoverpa armigera and specialist h assulta species and tissue differences
Pesticide Biochemistry and Physiology, 2020Co-Authors: Jiang Zhu, Christopher A Reilly, Kai Tian, Xinghui QiuAbstract:Helicoverpa armigera and H. assulta are two of the few insects that can feed on hot pepper fruits. Capsaicin and dihydrocapsaicin (i.e., Capsaicinoids) are the principal pungent compounds in hot peppers. To explore possible molecular mechanisms of adaptation that allow these two species to consume Capsaicinoids, the capacity of the three detoxification tissues (fat body, midgut, and Malpighian tubule) of the two pests, to metabolically degrade capsaicin and dihydrocapsaicin, was compared. The results showed that capsaicin and dihydrocapsaicin were metabolized by crude enzyme preparations from all three tissues of the two pests. Five metabolites of capsaicin, and five metabolites of dihydrocapsaicin were identified. Tissue and species differences in the degree of capsaicin and dihydrocapsaicin metabolism were observed. The specialist H. assulta had an overall greater capacity to degrade the Capsaicinoids compared to the generalist H. armigera. Further, the midgut was the most significant contributor to Capsaicinoid metabolism. The notably high specific activity in Malpighian tubules of H. armigera also further highlights the significance of this organ in xenobiotic detoxification. Alkyl hydroxylation and dehydrogenation were the main pathways for the oxidative biotransformation of both capsaicin and dihydrocapsaicin by cytochrome P450s. This study provides evidence that enhanced metabolic decomposition of Capsaicinoids may be an adaptation explaining dietary preferences for Capsicum fruits by these two pests.
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Cytochrome P450-Dependent Modification of Capsaicinoids: Pharmacological Inactivation and Bioactivation Mechanisms
Role of Capsaicin in Oxidative Stress and Cancer, 2013Co-Authors: Christopher A ReillyAbstract:Capsaicinoids are the chemicals that make chili peppers “hot.” Human exposure to Capsaicinoids through their diet is frequent and often considerable. Capsaicinoids are also used in a variety of consumer products, nutraceutical, and pharmaceutical preparations, including pepper spray self-defense products, supplements for weight loss, and therapeutics for pain management, and antioxidant defense/cancer chemoprevention. In the human body, Capsaicinoids are rapidly degraded and/or modified by a variety of enzymatic processes that significantly alter the pharmacological and toxicological properties of the Capsaicinoids. This chapter provides as review of the enzymatic processes that appear to be critical in the clearance of Capsaicinoids from cells in the human body, with an emphasis on Cytochrome P450-dependent processes. Additionally, the consequences of P450-mediated Capsaicinoid metabolism with respect to the biological activity of Capsaicinoids as dietary supplements and therapeutic molecules are discussed.
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assessment of pepper spray product potency in asian and caucasian forearm skin using transepidermal water loss skin temperature and reflectance colorimetry
Journal of Applied Toxicology, 2006Co-Authors: Lynn K Pershing, Judy L Corlett, Christopher A Reilly, Dennis J CrouchAbstract:Historically, pepper spray product potency has been established using a taste test evaluation. A taste test is subjective and may not be appropriate for assessing pepper potency in skin. The current study evaluated chemically diverse pepper sprays in human forearm skin using three objective, noninvasive parameters: transepidermal water loss, skin surface temperature and erythema, as a means for assessing dermal pharmacology, toxicology and product potency. Five commercial pepper spray products containing various Capsaicinoid analogs at various concentrations were evaluated in duplicate on volar forearms of six Caucasians and six Asians using a 10 min exposure. Mean surface skin temperature, transepidermal water loss results were highly variable and therefore did not demonstrate dose responsive behavior to increasing Capsaicinoid concentrations. Erythema, as measured by increases in a* (reflected light in the red-to-green color spectrum) of the L*a*b* uniform color scale, was superior among parameters evaluated in discriminating pepper spray potency and correlated well with the relative and total Capsaicinoid concentration in the products. Products containing greater than 16 mg ml(-1) Capsaicinoid concentration produced greater erythema responses in Caucasians than Asians. Asians responded greater to the synthetic analog, nonivamide, than to mixtures of Capsaicinoids, while Caucasians responded equally to both Capsaicinoid analogs. Thus, pepper spray product potency in human skin reflects the total Capsaicinoid concentration, the specific capsaicin analog(s) present, and the race of the individual exposed. The finding that the reflectance colorimeter a* scale can differentiate these parameters in skin will have a significant impact on evaluating the use and efficacy of pepper spray products in humans. Language: en
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Metabolism of Capsaicinoids by P450 enzymes: a review of recent findings on reaction mechanisms, bio-activation, and detoxification processes.
Drug metabolism reviews, 2006Co-Authors: Christopher A Reilly, Garold S. YostAbstract:Capsaicinoids are botanical irritants present in chili peppers. Chili pepper extracts and Capsaicinoids are common dietary constituents and important pharmaceutical agents. Use of these substances in modern consumer products and medicinal preparations occurs worldwide. Capsaicinoids are the principals of pepper spray self-defense weapons and several over-the-counter pain treatments as well as the active component of many dietary supplements. Capsaicinoids interact with the capsaicin receptor (a.k.a., VR1 or TRPV1) to produce acute pain and cough as well as long-term analgesia. Capsaicinoids are also toxic to many cells via TRPV1-dependent and independent mechanisms. Chemical modifications to Capsaicinoids by P450 enzymes decreases their potency at TRPV1 and reduces the pharmacological and toxicological phenomena associated with TRPV1 stimulation. Metabolism of Capsaicinoids by P450 enzymes also produces reactive electrophiles capable of modifying biological macromolecules. This review highlights data describing specific mechanisms by which P450 enzymes convert the Capsaicinoids to novel products and explores the relationship between Capsaicinoid metabolism and its effects on Capsaicinoid pharmacology and toxicology.
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structural and enzymatic parameters that determine alkyl dehydrogenation hydroxylation of Capsaicinoids by cytochrome p450 enzymes
Drug Metabolism and Disposition, 2005Co-Authors: Christopher A Reilly, Garold S. YostAbstract:Previous studies on the metabolism of Capsaicinoids, natural products isolated from chili peppers, demonstrated the production of unique macrocyclic, alkyl dehydrogenated, ω-, and ω-1-hydroxylated products. This study investigated the structural and enzymatic parameters that direct selective alkyl dehydrogenation and hydroxylation of Capsaicinoids, using a variety of structurally related Capsaicinoid analogs and cytochrome P450 (P450) enzymes. CYP2C9 preferentially catalyzed alkyl dehydrogenation, whereas CYP2E1 and 3A4 catalyzed ω- and ω-1-hydroxylation, respectively. Analysis of incubations containing various P450s and structural variants of capsaicin by liquid chromatography-tandem mass spectrometry demonstrated similarities in the rate of Capsaicinoid metabolism, but marked differences in the metabolite profiles. Production of macrocyclic and ω-1-hydroxylated metabolites from the various Capsaicinoids was dependent on the structure of the alkyl terminus and P450 enzyme. A tertiary carbon at the ω-1 position, coupled to an adjacent unsaturated bond at the ω-2,3 position, enhanced the formation of the macrocyclic and dehydrogenated metabolites and were requisite structural features for ω-1-hydroxylated product formation. Conversely, substrates lacking these structural features were efficiently oxidized to the ω-hydroxylated metabolite. These data were consistent with our hypothesis that metabolism of the alkyl portion of Capsaicinoids was governed, in part, by the stability and propensity to form an intermediate radical and a carbocation, and a direct interaction between the alkyl terminus and the heme of many P450 enzymes. These results provided valuable insights into potential mechanisms by which P450s metabolize Capsaicinoids and highlight critical chemical features that may also govern the metabolism of structurally related compounds including fatty acids, monoter-penes, and isoprenoids.
Muenduen Phisalaphong - One of the best experts on this subject based on the ideXlab platform.
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ultrasound assisted extraction of Capsaicinoids from capsicum frutescens on a lab and pilot plant scale
Ultrasonics Sonochemistry, 2008Co-Authors: Sumate Boonkird, Chada Phisalaphong, Muenduen PhisalaphongAbstract:Abstract The influence of operating parameters (solvent type, powder to solvent ratio and temperature) on the ultrasonically assisted extraction of Capsaicinoids from dried Capsicum frutescens (fruit) was studied. From the economic perspective, the suitable condition for Capsaicinoid extraction by indirect sonication in an ultrasonic bath with a working frequency of 35 kHz was at a ratio of 1 g of solid material: 5 ml of 95% (v/v) ethanol, 45 °C, where 85% of the Capsaicinoids were removed from the raw material in 3 h. In an experimental pilot study in 20-l extraction tank at the fixed ultrasonic frequency of 26 kHz and 70 kHz, the recovery of Capsaicinoids was 76% and 70%, respectively. It was shown that the ultrasonic extraction produced a significant reduction in extraction time at a lower operational temperature than under a conventional industrial hot maceration process.
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ultrasound assisted extraction of Capsaicinoids from capsicum frutescens on a lab and pilot plant scale
Ultrasonics Sonochemistry, 2008Co-Authors: Sumate Boonkird, Chada Phisalaphong, Muenduen PhisalaphongAbstract:The influence of operating parameters (solvent type, powder to solvent ratio and temperature) on the ultrasonically assisted extraction of Capsaicinoids from dried Capsicum frutescens (fruit) was studied. From the economic perspective, the suitable condition for Capsaicinoid extraction by indirect sonication in an ultrasonic bath with a working frequency of 35 kHz was at a ratio of 1g of solid material: 5 ml of 95% (v/v) ethanol, 45 degrees C, where 85% of the Capsaicinoids were removed from the raw material in 3h. In an experimental pilot study in 20-l extraction tank at the fixed ultrasonic frequency of 26 kHz and 70 kHz, the recovery of Capsaicinoids was 76% and 70%, respectively. It was shown that the ultrasonic extraction produced a significant reduction in extraction time at a lower operational temperature than under a conventional industrial hot maceration process.
Dennis J Crouch - One of the best experts on this subject based on the ideXlab platform.
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assessment of pepper spray product potency in asian and caucasian forearm skin using transepidermal water loss skin temperature and reflectance colorimetry
Journal of Applied Toxicology, 2006Co-Authors: Lynn K Pershing, Judy L Corlett, Christopher A Reilly, Dennis J CrouchAbstract:Historically, pepper spray product potency has been established using a taste test evaluation. A taste test is subjective and may not be appropriate for assessing pepper potency in skin. The current study evaluated chemically diverse pepper sprays in human forearm skin using three objective, noninvasive parameters: transepidermal water loss, skin surface temperature and erythema, as a means for assessing dermal pharmacology, toxicology and product potency. Five commercial pepper spray products containing various Capsaicinoid analogs at various concentrations were evaluated in duplicate on volar forearms of six Caucasians and six Asians using a 10 min exposure. Mean surface skin temperature, transepidermal water loss results were highly variable and therefore did not demonstrate dose responsive behavior to increasing Capsaicinoid concentrations. Erythema, as measured by increases in a* (reflected light in the red-to-green color spectrum) of the L*a*b* uniform color scale, was superior among parameters evaluated in discriminating pepper spray potency and correlated well with the relative and total Capsaicinoid concentration in the products. Products containing greater than 16 mg ml(-1) Capsaicinoid concentration produced greater erythema responses in Caucasians than Asians. Asians responded greater to the synthetic analog, nonivamide, than to mixtures of Capsaicinoids, while Caucasians responded equally to both Capsaicinoid analogs. Thus, pepper spray product potency in human skin reflects the total Capsaicinoid concentration, the specific capsaicin analog(s) present, and the race of the individual exposed. The finding that the reflectance colorimeter a* scale can differentiate these parameters in skin will have a significant impact on evaluating the use and efficacy of pepper spray products in humans. Language: en
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effects of vehicle on the uptake and elimination kinetics of Capsaicinoids in human skin in vivo
Toxicology and Applied Pharmacology, 2004Co-Authors: Lynn K Pershing, Judy L Corlett, Christopher A Reilly, Dennis J CrouchAbstract:While the physiologic and molecular effects of Capsaicinoids have been extensively studied in various model systems by a variety of administration routes, little is known about the uptake and elimination kinetic profiles in human skin following topical exposure. The present study evaluated the uptake and elimination kinetics of Capsaicinoids in human stratum corneum following a single topical exposure to 3% solutions containing 55% capsaicin, 35% dihydrocapsaicin, and 10% other analogues prepared in three vehicles: mineral oil (MO), propylene glycol (PG), and isopropyl alcohol (IPA). Capsaicinoid solutions were evaluated simultaneously in a random application pattern on the volar forearms of 12 subjects using a small, single 150-microg dose. Capsaicin and dihydrocapsaicin were recovered from human skin using commercial adhesive discs to harvest stratum corneum from treated sites. Capsaicinoids were extracted from the stratum corneum-adhesive discs and quantified by liquid chromatography/mass spectroscopy (LC/MS). Both Capsaicinoids were detected in stratum corneum 1 min after application with all vehicles and achieved a pseudo-steady state shortly thereafter. IPA delivered three times greater capsaicin and dihydrocapsaicin into the human stratum corneum than PG or MO at all time points investigated. The Cmax of capsaicin in IPA, PG, and MO was 16.1, 6.2, and 6.5 microg, respectively. The dihydrocapsaicin content was 60% of capsaicin with all vehicles. The estimated T(half) of capsaicin and dihydrocapsaicin in the three vehicles was similar (24 h). Thus, maximal cutaneous Capsaicinoid concentrations were achieved quickly in the human stratum corneum and were concentration and vehicle dependent. In contrast, Capsaicinoid half-life was long and vehicle independent.
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Detection of Pepper Spray Residues on Fabrics Using Liquid Chromatography-Mass Spectrometry
Journal of Forensic Sciences, 2002Co-Authors: Christopher A Reilly, Dennis J Crouch, Garold S. Yost, David M. AndrenyakAbstract:The analysis of trace evidence for the presence of biological and nonbiological residues is an integral part of many criminal and civil investigations and the use of pepper spray self-defense weaponry by the general public, criminals, and law enforcement agents is increasing. Therefore, the possibility that pepper spray residues may be present as forensic evidence at crime scenes or from civil disturbances becomes more likely. We have investigated the effects of storage and washing on the detection of pepper spray residues (i.e., Capsaicinoids) on cotton, cotton-polyester blend, wool, and nylon fabrics. The concentrations of the Capsaicinoid analogues on the fabrics decreased between 5 to 60% during six months of storage when compared with samples of each fabric type that were prepared and analyzed at the onset of the stability study (Time 0). The rate of disappearance of the Capsaicinoids was analogue specific. Degradation of the Capsaicinoids was independent of fabric type and temperature of storage. We also investigated the effects of washing the fabrics on the detection of Capsaicinoids. Fabrics were washed with water, 1% detergent, 1% bleach, or 5%Spray and Wash™. Water was the least effective method of removing the Capsaicinoids from the fabric and bleach the most effective. Retention of the Capsaicinoids on the fabrics following washing was affected by fabric type as well as the chemical properties of the individual Capsaicinoid analogues. The uses and limitations of Capsaicinoid residue evidence as an indicator of exposure to pepper sprays or use of pepper sprays are discussed.
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quantitative analysis of Capsaicinoids in fresh peppers oleoresin capsicum and pepper spray products
Journal of Forensic Sciences, 2001Co-Authors: Christopher A Reilly, Dennis J Crouch, Garold S. YostAbstract:Liquid chromatography-mass spectrometry was used to identify and quantify the predominant Capsaicinoid analogues in extracts of fresh peppers, in oleoresin capsicum, and pepper sprays. The concentration of Capsaicinoids in fresh peppers was variable. Variability was dependent upon the relative pungency of the pepper type and geographical origin of the pepper. Nonivamide was conclusively identified in the extracts of fresh peppers, despite numerous reports that nonivamide was not a natural product. In the oleoresin capsicum samples, the pungency was proportional to the total concentration of Capsaicinoids and was related by a factor of approximately 15,000 Scoville Heat Units (SHU)/µg of total Capsaicinoids. The principle analogues detected in oleoresin capsicum were capsaicin and dihydrocapsaicin and appeared to be the analogues primarily responsible for the pungency of the sample. The analysis of selected samples of commercially available pepper spray products also demonstrated variability in the Capsaicinoid concentrations. Variability was observed among products obtained from different manufacturers as well as from different product lots from the same manufacturer. These data indicate that commercial pepper products are not standardized for Capsaicinoid content even though they are classified by SHU. Variability in the Capsaicinoid concentrations in oleoresin capsicum-based self-defense weapons could alter potency and ultimately jeopardize the safety and health of users and assailants.
Sumate Boonkird - One of the best experts on this subject based on the ideXlab platform.
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ultrasound assisted extraction of Capsaicinoids from capsicum frutescens on a lab and pilot plant scale
Ultrasonics Sonochemistry, 2008Co-Authors: Sumate Boonkird, Chada Phisalaphong, Muenduen PhisalaphongAbstract:Abstract The influence of operating parameters (solvent type, powder to solvent ratio and temperature) on the ultrasonically assisted extraction of Capsaicinoids from dried Capsicum frutescens (fruit) was studied. From the economic perspective, the suitable condition for Capsaicinoid extraction by indirect sonication in an ultrasonic bath with a working frequency of 35 kHz was at a ratio of 1 g of solid material: 5 ml of 95% (v/v) ethanol, 45 °C, where 85% of the Capsaicinoids were removed from the raw material in 3 h. In an experimental pilot study in 20-l extraction tank at the fixed ultrasonic frequency of 26 kHz and 70 kHz, the recovery of Capsaicinoids was 76% and 70%, respectively. It was shown that the ultrasonic extraction produced a significant reduction in extraction time at a lower operational temperature than under a conventional industrial hot maceration process.
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ultrasound assisted extraction of Capsaicinoids from capsicum frutescens on a lab and pilot plant scale
Ultrasonics Sonochemistry, 2008Co-Authors: Sumate Boonkird, Chada Phisalaphong, Muenduen PhisalaphongAbstract:The influence of operating parameters (solvent type, powder to solvent ratio and temperature) on the ultrasonically assisted extraction of Capsaicinoids from dried Capsicum frutescens (fruit) was studied. From the economic perspective, the suitable condition for Capsaicinoid extraction by indirect sonication in an ultrasonic bath with a working frequency of 35 kHz was at a ratio of 1g of solid material: 5 ml of 95% (v/v) ethanol, 45 degrees C, where 85% of the Capsaicinoids were removed from the raw material in 3h. In an experimental pilot study in 20-l extraction tank at the fixed ultrasonic frequency of 26 kHz and 70 kHz, the recovery of Capsaicinoids was 76% and 70%, respectively. It was shown that the ultrasonic extraction produced a significant reduction in extraction time at a lower operational temperature than under a conventional industrial hot maceration process.
Carmelo Garcia Barroso - One of the best experts on this subject based on the ideXlab platform.
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Ontogenetic Variation of Individual and Total Capsaicinoids in Malagueta Peppers (Capsicum frutescens) during Fruit Maturation.
Molecules (Basel Switzerland), 2017Co-Authors: Oreto Fayos, Miguel Palma, Ana Aguiar, Ana Jiménez-cantizano, Marta Ferreiro-gonzález, Ana Garcés-claver, Julian Martínez, Cristina Mallor, Ana Ruiz-rodríguez, Carmelo Garcia BarrosoAbstract:The ontogenetic variation of total and individual Capsaicinoids (nordihydrocapsaicin (n-DHC), capsaicin (C), dihydrocapsaicin (DHC), homocapsaicin (h-C) and homodihydrocapsaicin (h-DHC)) present in Malagueta pepper (Capsicum frutescens) during fruit ripening has been studied. Malagueta peppers were grown in a greenhouse under controlled temperature and humidity conditions. Capsaicinoids were extracted using ultrasound-assisted extraction (UAE) and the extracts were analyzed by ultra-performance liquid chromatography (UHPLC) with fluorescence detection. A significant increase in the total content of Capsaicinoids was observed in the early days (between 12 and 33). Between day 33 and 40 there was a slight reduction in the total Capsaicinoid content (3.3% decrease). C was the major Capsaicinoid, followed by DHC, n-DHC, h-C and h-DHC. By considering the evolution of standardized values of the Capsaicinoids it was verified that n-DHC, DHC and h-DHC (dihydrocapsaicin-like Capsaicinoids) present a similar behavior pattern, while h-C and C (capsaicin-like Capsaicinoids) show different evolution patterns.
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Evolution of Capsaicinoids in Peter Pepper (Capsicum annuum var. annuum) During Fruit Ripening.
Chemistry & biodiversity, 2016Co-Authors: Gerardo F. Barbero, Miguel Palma, Ana Aguiar, Marta Ferreiro-gonzález, Julian Martínez, Ceferino Carrera, Ángel Olachea, Carmelo Garcia BarrosoAbstract:The evolution of individual and total contents of Capsaicinoids present in Peter peppers (Capsicum annuum var. annuum) at different ripening stages has been studied. Plants were grown in a glasshouse and the new peppers were marked in a temporal space of ten days. The extraction of Capsaicinoids was performed by ultrasound-assisted extraction with MeOH. The Capsaicinoids nordihydrocapsaicin (n-DHC), capsaicin, dihydrocapsaicin, homocapsaicin, and homodihydrocapsaicin were analyzed by ultraperformance liquid chromatography (UHPLC)-fluorescence and identified by UHPLC-Q-ToF-MS. The results indicate that the total Capsaicinoids increase in a linear manner from the first point of harvest at ten days (0.283 mg/g FW) up to 90 days, at which point they reach a concentration of 1.301 mg/g FW. The evolution as a percentage of the individual Capsaicinoids showed the initial predominance of capsaicin, dihydrocapsaicin, and n-DHC. Dihydrocapsaicin was the major Capsaicinoid up to day 50 of maturation. After 50 days, capsaicin became the major Capsaicinoid as the concentration of dihydrocapsaicin fell slightly. The time of harvest of Peter pepper based on the total Capsaicinoids content should be performed as late as possible. In any case, harvesting should be performed before overripening of the fruit is observed.
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Capsaicinoid Contents in Peppers and Pepper-Related Spicy Foods
International Journal of Food Properties, 2015Co-Authors: Gerardo F. Barbero, Ali Liazid, Miguel Palma, Latifa Azaroual, Carmelo Garcia BarrosoAbstract:The quantification of the major Capsaicinoids, namely nordihydrocapsaicin, capsaicin, dihydrocapsaicin, homocapsaicin, and homodihydrocapsaicin, present in spicy foods made from peppers has been performed. The capsaicin content is directly related to the pungency properties of foods that contain hot peppers. The samples studied included 10 different dried hot peppers, 19 hot sauces, 4 kinds of paprika, and 4 different ketchups. The range of concentrations of Capsaicinoids found were as follows: dried hot peppers (554.1–1705.9 mol kg−1), paprikas (582.0–665.0 mol kg−1), spicy ketchups (4.0–12.4 mol kg−1), and hot sauces (4.6–843.8 mol kg−1). Variability in the Capsaicinoid content was found, with capsaicin and dihydrocapsaicin present at the highest levels. The capsaicin content was generally higher than the dihydrocapsaicin content.
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evolution of total and individual Capsaicinoids in peppers during ripening of the cayenne pepper plant capsicum annuum l
Food Chemistry, 2014Co-Authors: Gerardo F. Barbero, Aurora G Ruiz, Jesus C Vera, Ali Liazid, Miguel Palma, Carmelo Garcia BarrosoAbstract:Abstract The evolution of total Capsaicinoids and the individual contents of the five major Capsaicinoids: nordihydrocapsaicin, capsaicin, dihydrocapsaicin, homocapsaicin and homodihydrocapsaicin present in the Cayenne pepper ( Capsicum annuum L.), during fruit ripening, has been established. Capsaicinoids begin to accumulate gradually in the peppers from the beginning of its development up to a maximum concentration (1789 μmol/Kg FW). From this time there is initially a sharp decrease in the total Capsaicinoid content (32%), followed by a gradual decrease until day 80 of ripening. The two major Capsaicinoids present in the Cayenne pepper are capsaicin and dihydrocapsaicin, which represent between 79% and 90%, respectively, of total Capsaicinoids depending on fruit ripening. The relative content of capsaicin differs from the evolution of the other four Capsaicinoids studied.
