Special Issue "Carotenoids"
Quicklinks
A special issue of Molecules (ISSN 1420-3049).
Deadline for manuscript submissions: closed (30 November 2011)
Special Issue Editor
Guest Editor
Dr. Hans-Richard Sliwka
Department of Chemistry, Norwegian University of Science and Technology, 7491 Trondheim, Norway
E-Mail: richard.sliwka@ntnu.no
Special Issue Information
Dear Colleagues,
Carotenoids are, by definition, polyenes of 6-14 conjugated double bonds, stabilized by methyl groups and cyclohexene endrings. Straight chain polyenes without these stabilizations only reach 5 double bonds. The major part of the 750 natural carotenoids occurs with 9-11 conjugated double bonds, which may be the effective range regarding stability and activity. Such carotenoids are given as prime examples in textbooks to explain UV-VIS spectroscopy. Carotenoids with a considerably increased number of double bonds have been synthesized to approach λ∞, the magic absorption limit.
Carotenoids participate in photosynthesis and are, therefore, biosynthesized in plants and alga. Although photosynthesis may appear a long procedure taking place during hours of sunlight exposition the photophysical examination of light absorbing by carotenoids has reached the incredible short span of femtoseconds. In water based environments carotenoids aggregate to micelles and vesicles; increasing effort is directed to study these nano sized structures. Carotenoid chemists have traditionally focused on structure elucidation and on synthesis and various natural occurring carotenoids are also available by synthesis. Eight carotenoids are offered industrially in considerable amounts and are marketed as food and feed colors. Since most carotenoids are hydrophobic, they add to proteins for passing aqueous environments. Hydrophobicity also obstructs an all-purpose assignment of carotenoids and they need extensive formulation before introduced in water-based applications, e.g. as food colors. The pharmacological importance of carotenoids has been limited; a few modified carotenoids for the treatment of cardiovascular and ophthalmological diseases pass now clinical or pharmacokinetic studies. Carotenoids function as molecular wires and modified carotenoids have been developed for electrochemical and spectroscopic research.
Carotenoids are best known as antioxidants. Nevertheless, it is still not clear whether the intact carotenoid is the active agent or one of its oxidative degradation products. A practical impact of carotenoids to the development of chemistry cannot be underestimated: the purification method “chromatography” was invented with these colorful compounds. Carotenoids are the subject of substantial interdisciplinary research. It is hoped that the special issue of Molecules attract researchers who present the various aspects of carotenoid research.
Hans-Richard Sliwka
Guest Editor
Submission
Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. Papers will be published continuously (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.
Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are refereed through a peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Molecules is an international peer-reviewed Open Access monthly journal published by MDPI.
Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1400 CHF (Swiss Francs).
Keywords
- aggregation
- amphiphiles
- antioxidants
- bioorganic chemistry
- biophysics
- biosynthesis
- biotransformations
- carbocations
- carotenoids
- cations
- chirality
- chromophores
- chromatography
- conjugation
- cyclic voltammetry
- density functional calculations
- electron transfer
- energy transfer
- fatty acids
- fluorescence
- lipids
- membranes
- molecular electronics
- molecular modeling
- monolayers
- nanostructures
- natural products
- nonlinear optics
- photophysics
- photosynthesis
- radical ions
- radicals
- self-assembly
- singlet oxygen
- structure-activity relationships
- surfactants
- total synthesis
- UV/Vis spectroscopy
- vesicles
- wittig reactions
Published Papers (15 papers)
|
Received: 17 November 2011; in revised form: 3 December 2011 / Accepted: 8 December 2011 / Published: 16 December 2011
Show/Hide Abstract
| Download PDF Full-text (213 KB)
Abstract: The human skin, as the boundary organ between the human body and the environment, is under the constant influence of free radicals (FR), both from the outside in and from the inside out. Carotenoids are known to be powerful antioxidant substances playing an essential role in the reactions of neutralization of FR (mainly reactive oxygen species ROS). Carotenoid molecules present in the tissue are capable of neutralizing several attacks of FR, especially ROS, and are then destroyed. Human skin contains carotenoids, such as α-, γ-, β-carotene, lutein, zeaxanthin, lycopene and their isomers, which serve the living cells as a protection against oxidation. Recent studies have reported the possibility to investigate carotenoids in human skin quickly and non-invasively by spectroscopic means. Results obtained from in-vivo studies on human skin have shown that carotenoids are vital components of the antioxidative protective system of the human skin and could serve as marker substances for the overall antioxidative status. Reflecting the nutritional and stress situation of volunteers, carotenoids must be administered by means of antioxidant-rich products, e.g., in the form of fruit and vegetables. Carotenoids are degraded by stress factors of any type, inter alia, sun radiation, contact with environmental hazards, illness, etc. The kinetics of the accumulation and degradation of carotenoids in the skin have been investigated.
|
Nancy L. Sheehan, Rolf P. G. van Heeswijk, Brian C. Foster, Humayoun Akhtar, Neera Singhal, Isabelle Seguin, Lina DelBalso, Marc Bourbeau, Bobby M. Chauhan, Mohammed-Rachid Boulassel, David M. Burger, Richard G. Lalonde and Donald William Cameron
Received: 9 December 2011; in revised form: 5 January 2012 / Accepted: 6 January 2012 / Published: 12 January 2012
Show/Hide Abstract
| Download PDF Full-text (285 KB)
Abstract: β-Carotene supplements are often taken by individuals living with HIV-1. Contradictory results from in vitro studies suggest that β-carotene may inhibit or induce cytochrome P450 enzymes and transporters. The study objective was to investigate the effect of β-carotene on the steady-state pharmacokinetics of nelfinavir and its active metabolite M8 in HIV-1 infected individuals. Twelve hour nelfinavir pharmacokinetic analysis was conducted at baseline and after 28 days of β-carotene supplementation (25,000 IU twice daily). Nelfinavir and M8 concentrations were measured with validated assays. Non-compartmental methods were used to calculate the pharmacokinetic parameters. Geometric mean ratios comparing day 28 to day 1 area under the plasma concentration-time curve (AUC0–12 h), maximum (Cmax) and minimum (Cmin) concentrations of nelfinavir and M8 are presented with 90% confidence intervals. Eleven subjects completed the study and were included in the analysis. There were no significant differences in nelfinavir AUC0–12 h and Cmin (−10%, +4%) after β-carotene supplementation. The M8 Cmin was increased by 31% while the M8 AUC0–12 h and Cmax were unchanged. During the 28 day period, mean CD4+ % and CD4+:CD8+ ratio increased significantly (p < 0.01). β-carotene supplementation increased serum carotene levels but did not cause any clinically significant difference in the nelfinavir and M8 exposure.
 |
|
Received: 30 November 2011; in revised form: 16 December 2011 / Accepted: 5 January 2012 / Published: 20 January 2012
Show/Hide Abstract
| Download PDF Full-text (1227 KB) | 
Abstract: In this Density Functional Theory study, it became apparent that astaxanthin (ASTA) may form metal ion complexes with metal cations such as Ca+2, Cu+2, Pb+2, Zn+2, Cd+2 and Hg+2. The presence of metal cations induces changes in the maximum absorption bands which are red shifted in all cases. Therefore, in the case of compounds where metal ions are interacting with ASTA, they are redder in color. Moreover, the antiradical capacity of some ASTA-metal cationic complexes was studied by assessing their vertical ionization energy and vertical electron affinity, reaching the conclusion that metal complexes are slightly better electron donors and better electron acceptors than ASTA.
|
|
Received: 25 October 2011; in revised form: 22 December 2011 / Accepted: 4 January 2012 / Published: 24 January 2012
Show/Hide Abstract
| Download PDF Full-text (1278 KB)
Abstract: Duchenne Muscular Dystrophy (DMD) is a common, inherited, incurable, fatal muscle wasting disease caused by deletions that disrupt the reading frame of the DMD gene such that no functional dystrophin protein is produced. Antisense oligonucleotide (AO)-directed exon skipping restores the reading frame of the DMD gene, and truncated, yet functional dystrophin protein is expressed. The aim of this study was to assess the efficiency of two novel rigid, cationic carotenoid lipids, C30-20 and C20-20, in the delivery of a phosphorodiamidate morpholino (PMO) AO, specifically designed for the targeted skipping of exon 45 of DMD mRNA in normal human skeletal muscle primary cells (hSkMCs). The cationic carotenoid lipid/PMO-AO lipoplexes yielded significant exon 45 skipping relative to a known commercial lipid, 1,2-dimyristoyl-sn-glycero-3-ethylphosphocholine (EPC).
|
|
Received: 5 December 2011; in revised form: 28 January 2012 / Accepted: 3 February 2012 / Published: 7 February 2012
Show/Hide Abstract
| Download PDF Full-text (249 KB)
Abstract: The impact of spent coffee grounds on carotenoid and chlorophyll content in lettuce (Lactuca sativa L. var. capitata) was evaluated. A greenhouse pot experiment was conducted with spent coffee amounts ranging from 0% to 20% (v/v). All evaluated pigments increased proportionally to spent coffee amounts. Lutein and β-carotene levels increased up to 90% and 72%, respectively, while chlorophylls increased up to 61%. Biomass was also improved in the presence of 2.5% to 10% spent coffee, decreasing for higher amounts. Nevertheless, all plants were characterized by lower organic nitrogen content than the control ones, inversely to the spent coffee amounts, pointing to possible induced stress. Collected data suggests that plants nutritional features, with regards to these bioactive compounds, can be improved by the presence of low amounts of spent coffee grounds (up to 10%). This observation is particularly important because soil amendment with spent coffee grounds is becoming increasingly common within domestic agriculture. Still, further studies on the detailed influence of spent coffee bioactive compounds are mandatory, particularly regarding caffeine.
|
|
Received: 30 November 2011; in revised form: 26 January 2012 / Accepted: 1 February 2012 / Published: 10 February 2012
Show/Hide Abstract
| Download PDF Full-text (691 KB)
Abstract: Carotenoids are known for their antioxidant activity and health promoting effects. One of the richest sources of carotenoids are carrots. However, about 25% of the annual production is regarded as by-products due to strict market policies. The aim of this study was to extract carotenoids from those by-products. Conventional carotenoid extraction methods require the use of organic solvents, which are costly, environmentally hazardous, and require expensive disposal procedures. Pressurized liquid extraction (PLE) utilizes conventional solvents at elevated temperatures and pressure, and it requires less solvent and shorter extraction times. The extraction solvent of choice in this study was ethanol, which is a solvent generally recognized as safe (GRAS). The extraction procedure was optimized by varying the extraction time (2–10 min) and the temperature (60–180 °C). β-Carotene was used as an indicator for carotenoids content in the carrots. The results showed that time and temperatures of extraction have significant effect on the yield of carotenoids. Increasing the flush volume during extraction did not improve the extractability of carotenoids, indicating that the extraction method was mainly desorption/diffusion controlled. Use of a dispersing agent that absorbs the moisture content was important for the efficiency of extraction. Analysing the content of β-carotene at the different length of extraction cycles showed that about 80% was recovered after around 20 min of extraction.
|
|
Received: 18 January 2012; in revised form: 13 February 2012 / Accepted: 13 February 2012 / Published: 20 February 2012
Show/Hide Abstract
| Download PDF Full-text (289 KB)
Abstract: Oxidative stress and inflammation are established processes contributing to cardiovascular disease caused by atherosclerosis. However, antioxidant therapies tested in cardiovascular disease such as vitamin E, C and β-carotene have proved unsuccessful at reducing cardiovascular events and mortality. Although these outcomes may reflect limitations in trial design, new, more potent antioxidant therapies are being pursued. Astaxanthin, a carotenoid found in microalgae, fungi, complex plants, seafood, flamingos and quail is one such agent. It has antioxidant and anti-inflammatory effects. Limited, short duration and small sample size studies have assessed the effects of astaxanthin on oxidative stress and inflammation biomarkers and have investigated bioavailability and safety. So far no significant adverse events have been observed and biomarkers of oxidative stress and inflammation are attenuated with astaxanthin supplementation. Experimental investigations in a range of species using a cardiac ischaemia-reperfusion model demonstrated cardiac muscle preservation when astaxanthin is administered either orally or intravenously prior to the induction of ischaemia. Human clinical cardiovascular studies using astaxanthin therapy have not yet been reported. On the basis of the promising results of experimental cardiovascular studies and the physicochemical and antioxidant properties and safety profile of astaxanthin, clinical trials should be undertaken.
|
|
Received: 4 January 2012; in revised form: 30 January 2012 / Accepted: 3 February 2012 / Published: 21 February 2012
Show/Hide Abstract
| Download PDF Full-text (410 KB)
Abstract: Flavonoids and carotenoids with rich structural diversity are ubiquitously present in the plant kingdom. Flavonoids, and especially their glycosides, are more hydrophilic than most carotenoids. The interaction of flavonoids with carotenoids occurs accordingly at water/lipid interfaces and has been found important for the functions of flavonoids as antioxidants in the water phase and especially for the function of carotenoids as antioxidants in the lipid phase. Based on real-time kinetic methods for the fast reactions between (iso)flavonoids and radicals of carotenoids, antioxidant synergism during protection of unsaturated lipids has been found to depend on: (i) the appropriate distribution of (iso)flavonoids at water/lipid interface, (ii) the difference between the oxidation potentials of (iso)flavonoid and carotenoid and, (iii) the presence of electron-withdrawing groups in the carotenoid for facile electron transfer. For some (unfavorable) combinations of (iso)flavonoids and carotenoids, antioxidant synergism is replaced by antagonism, despite large potential differences. For contact with the lipid phase, the lipid/water partition coefficient is of importance as a macroscopic property for the flavonoids, while intramolecular rotation towards coplanarity upon oxidation by the carotenoid radical cation has been identified by quantum mechanical calculations to be an important microscopic property. For carotenoids, anchoring in water/lipid interface by hydrophilic groups allow the carotenoids to serve as molecular wiring across membranes for electron transport.
|
|
Received: 10 December 2011; in revised form: 14 February 2012 / Accepted: 15 February 2012 / Published: 22 February 2012
Show/Hide Abstract
| Download PDF Full-text (2252 KB)
Abstract: The mechanisms of suppression and enhancement of photocurrent/conversion efficiency (performance) in dye-sensitized solar cells, using carotenoid and chlorophyll derivatives as sensitizers, were compared systematically. The key factor to enhance the performance was found to be how to minimize interaction among the excited-state dye-sensitizer(s). In a set of retinoic-acid (RA) and carotenoic-acid (CA) sensitizers, having n conjugated double bonds, CA7 gave rise to the highest performance, which was reduced toward RA5 and CA13. The former was ascribed to the generation of triplet and the resultant singlet-triplet annihilation reaction, while the latter, to the intrinsic electron injection efficiency. In a set of shorter polyene sensitizers having different polarizabilities, the one with the highest polarizability (the highest trend of aggregate formation) exhibited the higher performance toward the lower dye concentration and the lower light intensity, contrary to our expectation. This is ascribed to a decrease in the singlet-triplet annihilation reaction. The performance of cosensitization, by a pair of pheophorbide sensitizers without and with the central metal, Mg or Zn, was enhanced by the light absorption (complementary rather than competitive), the transition-dipole moments (orthogonal rather than parallel) and by the pathways of electron injection (energetically independent rather than interactive).
|
|
Received: 9 January 2012; in revised form: 21 February 2012 / Accepted: 22 February 2012 / Published: 7 March 2012
Show/Hide Abstract
| Download PDF Full-text (519 KB)
Abstract: A listing of carotenoids with heteroatoms (X = F, Cl, Br, I, Si, N, S, Se, Fe) directly attached to the carotenoid carbon skeleton has been compiled. The 178 listed carotenoids with C,H,X atoms demonstrate that the classical division of carotenoids into hydrocarbon carotenoids (C,H) and xanthophylls (C,H,O) has become obsolete.
|
|
Received: 22 December 2011; in revised form: 15 February 2012 / Accepted: 6 March 2012 / Published: 14 March 2012
Show/Hide Abstract
| Download PDF Full-text (684 KB)
Abstract: Carotenoids are natural fat-soluble pigments that provide bright coloration to plants and animals. Dietary intake of carotenoids is inversely associated with the risk of a variety of cancers in different tissues. Preclinical studies have shown that some carotenoids have potent antitumor effects both in vitro and in vivo, suggesting potential preventive and/or therapeutic roles for the compounds. Since chemoprevention is one of the most important strategies in the control of cancer development, molecular mechanism-based cancer chemoprevention using carotenoids seems to be an attractive approach. Various carotenoids, such as β-carotene, a-carotene, lycopene, lutein, zeaxanthin, β-cryptoxanthin, fucoxanthin, canthaxanthin and astaxanthin, have been proven to have anti-carcinogenic activity in several tissues, although high doses of β-carotene failed to exhibit chemopreventive activity in clinical trials. In this review, cancer prevention using carotenoids are reviewed and the possible mechanisms of action are described.
|
|
Received: 19 March 2012; in revised form: 30 March 2012 / Accepted: 31 March 2012 / Published: 2 April 2012
Show/Hide Abstract
| Download PDF Full-text (285 KB) | View HTML Full-text | Download PMC-XML Full-text
Abstract: Oral administration of β-carotene (BC) was found to exert opposite effects on plasma levels of vascular endothelial growth factor (VEGF) in two animal models. One study in nude mice injected via tail vein with hepatocarcinoma SK-Hep-1 cells showed that BC decreases the plasma VEGF level, whereas the other study in nude mice injected subcutaneously with prostate tumor PC-3 cells showed that BC increases the plasma VEGF level. Herein we investigated whether BC (0.5–20 μM) possesses diverse effects on VEGF secretion in SK-Hep-1, PC-3 and melanoma B16F10 cells. We found that incubation of SK-Hep-1 cells with BC (1–20 μM) for 6 h significantly decreased VEGF secretion, whereas BC (1–10 μM) significantly increased the VEGF secretion in PC-3 cells. However, these effects disappeared at 12 h of incubation. Similar effects occurred in VEGF mRNA and protein expression after treatment of SK-Hep-1 and PC-3 cells with BC for 6 h. In contrast, BC (0.5–20 μM) did not affect mRNA and protein expression and secretion of VEGF in B16F10 cells. We also found that the proliferation of SK-Hep-1 and B16F10 cells was significantly inhibited by 20 μM BC at 6 and 12 h of incubation, whereas the proliferation of PC-3 cells was significantly inhibited by 20 μM BC at 12 h of incubation. In summary, the present study demonstrated the tumor-specific effect of BC on VEGF secretion in different cancer cell lines.
|
|
Received: 6 February 2012; in revised form: 28 March 2012 / Accepted: 5 April 2012 / Published: 23 April 2012
Show/Hide Abstract
| Download PDF Full-text (275 KB) | View HTML Full-text | Download PMC-XML Full-text
Abstract: Oxidative stress has been considered universally and undeniably implicated in the pathogenesis of all major diseases, including those of the cardiovascular system. Oxidative stress activate transcriptional messengers, such as nuclear factor—κB, tangibly contributing to endothelial dysfunction, the initiation and progression of atherosclerosis, irreversible damage after ischemic reperfusion, and even arrhythmia, such as atrial fibrillation. Evidence is rapidly accumulating to support the role of reactive oxygen species (ROS) and reactive nitrogen species (RNS) as intracellular signaling molecules. Despite this connection between oxidative stress and cardiovascular disease (CVD), there are currently no recognized therapeutic interventions to address this important unmet need. Antioxidants that provide a broad, “upstream” approach via ROS/RNS quenching or free radical chain breaking seem an appropriate therapeutic option based on epidemiologic, dietary, and in vivo animal model data. Short-term dietary intervention trials suggest that diets rich in fruit and vegetable intake lead to improvements in coronary risk factors and reduce cardiovascular mortality. Carotenoids are such abundant, plant-derived, fat-soluble pigments that functions as antioxidants. They are stored in the liver or adipose tissue, and are lipid soluble by becoming incorporated into plasma lipoprotein particles during transport. For these reasons, carotenoids may represent one plausible mechanism by which fruits and vegetables reduce the risk of chronic diseases as cardiovascular disease (CVD). This review paper outlines the role of carotenoids in maintaining cardiac health and cardioprotection mediated by several mechanisms including redox signaling.
|
|
Received: 22 March 2012; in revised form: 17 April 2012 / Accepted: 19 April 2012 / Published: 30 April 2012
Show/Hide Abstract
| Download PDF Full-text (305 KB)
Abstract: Carotenoids are substantially hydrophobic antioxidants. Hydrophobicity is this context is rather a disadvantage, because their utilization in medicine as antioxidants or in food chemistry as colorants would require some water dispersibility for their effective uptake or use in many other ways. In the past 15 years several attempts were made to synthetize partially hydrophilic carotenoids. This review compiles the recently synthetized hydrophilic carotenoid derivatives.
|
|
Received: 7 February 2012; in revised form: 4 May 2012 / Accepted: 8 May 2012 / Published: 11 May 2012
Show/Hide Abstract
| Download PDF Full-text (227 KB)
Abstract: The stability of formulated carotenoid diets during feed processing and under different storage conditions were studied. All carotenoid diets were split into two groups with one group containing BHT (acting as an antioxidant) at 250 ppm and the other without BHT. The experiment was divided into two parts. First, all diets were evaluated in total carotenoid (TC) loss during feed processing, in dry mixed feeds after being processed and dried. In the final part, the completed dietary carotenoids were stored in an aluminum foil bag, the top of which was sealed with a bag sealer and kept under different storage conditions at 26–28 °C and 4 °C. The stability of the TC was observed during an 8-week trial period. The results showed that the diet pelleting process did not affect the carotenoid content of the diets, and the best storage temperature for the formulated carotenoid diet was at 4 °C. However, an antioxidant was added to assist in energy saving before feed processing. Thus, the addition of BHT at 250 ppm can be done at normal room temperature in order to reduce oxidation that might cause a loss of TC quantities in diets.
|
Planned Papers
Type of Paper: Article
Title: Growth Inhibition of Human Hepatoma SK-Hep-1 Cells by β-apo-8'-carotenal in Relation to Enhanced Gap Junctional Intercellular communication
Authors: Chih-Min Yang, Huei-Yan Chen and Miao-Lin Hu *
Affiliations: Department of Food Science and Biotechnology, National Chung HsingUniversity, Taichung, Taiwan 402; E-mail: mlhuhu@nchu.edu.tw
Abstract: Epidemiologic studies suggest that elevated intakes of fruits and vegetables rich in β-carotene (BC) are associated with reduced risks of cancer. In vitro studies have shown that BC inhibits proliferation of several types of cancer cells. However, little is known whether B Cmetabolites exert anti-proliferative action, particularly inhepato cellular carcinoma, the major causes of cancer death in Taiwan, SK-Hep-1 cells. In this study, we investigated the anti-proliferative effects and the possible mechanisms of 5-20 μM of β-apo-8’-carotenal (BAC), a major oxidative intermediate product of BC, in comparison with BC (20 μM) in SK-Hep-1 cells. Results reveal that BAC significantly inhibited the proliferation of SK-Hep-1 cells at 2 h of incubation. Mechanistically, BAC: (1) induced apoptosis; (2) enhanced GJIC activity; (3) increased protein and mRNA expression of connexin 43; (4) increased the levels of intracellular calcium; and (5) increased DNA fragmentation in SK-Hep-1 cells. Importantly, all of these actions of BAC were stronger than those of BC at the same concentration (20 μM). In summary, this study demonstrates that BAC inhibits SK-Hep-1 cells proliferation and induces apoptosis, and this effect is associated with enhanced GJIC and connexin 43 expression.
Type of Paper: Review
Title: Terpenoids from Copaiba (Copaifera ssp) Oils
Authors: Valdir Florencio Veiga Jr 1; Lidiam Maia Leandro 1; Fabiano Souza Vargas 1, Jamilly Kelly Oliveira Neves 2, Jose Alexsandro Silva 2
Affiliation: 1 Universidade Federal do Amazonas, Chemistry Department, Manaus-AM, Brazil
2 Universidade Estadual da Paraiba, Pharmacy Department, Campina Grande-PB, Brazil; E-Mail: valdirveiga@ufam.edu.br
Abstract: Copaiba oils are oleoresins exudated by the trunk of the trees from Copaifera (Fabaceae) species. The oleoresin is a solution of diterpenoids, specially mono and di-acids, solubilized by hidrocarbon sesquiterpenes. The diterpenes, labdanes, clerodanes and kauranes, are different at each Copaifera specie and are related to several biological activities, from anti-tumoral to embriotoxic, that are still been described. This review presents the structure from this bioactive terpenoids.
Type of Paper: Review
Title: Cancer Chemoprevention by Carotenoids
Authors: Toshiya Kuno 1,* and Takuji Tanaka 2
Affiliation: 1 Department of Tumor Pathology, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu 501-1194, Japan; Tel +81 058 230 6225; Fax +81 58 230 6226, E-mail: tkuno@gifu-u.ac.jp
2 Director of The Tohkai Cytopathology Institute: Cancer Research and Prevention (TCI-CaRP). 5-1-2 Minami-Uzura, Gifu 500-8285, Japan; Phone: +81 58 273 4399; Fax: +81 58 273 4392, E-mail: takutt@toukaisaibou.co.jp
Abstract: Carotenoids are natural, fat-soluble pigments that provide bright coloration to plants and animals. Dietary intake of carotenoids is inversely associated with the risk of a variety of cancers in different tissues. Preclinical studies show that some carotenoids have potent antitumor effects in vitro and in vivo studies, suggesting potential preventive and therapeutic roles for the compounds. Since chemoprevention is one of the most important strategies in the field of cancer control, molecular mechanism-based cancer chemoprevention by carotenoids seems to be very attractive method. Various carotenoids, including alpha-carotene, beta-carotene, lycopene, lutein, cryptoxanthin and astaxanthin, have been proven to have anticarcinogenic activity in several tissues. In this review, possible molecular targets for cancer prevention by carotenoids are overviewed, and some examples of cancer preventive carotenoids are presented.
Last update: 14 July 2011
