Institut für Mangostan & natürliche Antioxidantien

LYCOPIN (Lycopene)

Aktuelle wissenschaftliche Studien | 11-30

11: Int J Food Sci Nutr. 2008 Jun 18:1-9. [Epub ahead of print]
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Carotenoid content and in vitro bioaccessibility of lycopene from guava (Psidium guajava) and watermelon (Citrullus lanatus) by high-performance liquid chromatography diode array detection.

Chandrika UG, Fernando KS, Ranaweera KK.

Department of Biochemistry, Faculty of Medical Sciences.

The carotenoid content and in vitro accessibility of the 'Sugar baby' variety of watermelon and the 'Horana red' variety of guava from Sri Lanka was determined using high-performance liquid chromatography. The high-performance liquid chromatography chromatogram showed that the Guava 'Horana red' variety contained almost exclusively lycopene (45.3+/-8.0microg/g fresh weight (FW)), with a small amount of lutein (2.1+/-0.6microg/g FW), beta-carotene (2.0+/-0.2microg/g FW) and beta-cryptoxanthin. As far as carotenoids in the sugar baby variety of watermelon are concerned, it contained lycopene, lutein and beta-carotene of 37.2+/-4.0microg/g FW, 2.1+/-0.6microg/g FW and 0.3+/-1microg/g FW, respectively. The studies showed that guava contains more lycopene (45.3+/-8.0microg/g FW) than watermelon (37.2+/-4.0microg/g FW), and that the in vitro accessibility of lycopene in guava (73%) is more than that in watermelon (25.8%). Therefore it can be concluded that guava can be used as a better lycopene source than watermelon.

PMID: 18608542 [PubMed - as supplied by publisher]

12: Br J Nutr. 2008 Jun 13:1-8. [Epub ahead of print]
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Plasma carotenoids and diabetic retinopathy.

Brazionis L, Rowley K, Itsiopoulos C, O'Dea K.

Department of Medicine, University of Melbourne (St Vincent's Hospital), Melbourne, VIC 3065, Australia.

Diabetic retinopathy increases with duration of diabetes and may be associated with carotenoid status. Carotenoids alter the pro-oxidation/antioxidation balance, and circulating levels depend largely on dietary intake. Lower levels have been reported in diabetes and age-related macular degeneration; however, little is known of the relationship between carotenoids and diabetic complications. Consequently, the purpose of the present study was to evaluate the relationship between plasma carotenoids and diabetic retinopathy. We assessed the carotenoid-retinopathy relationship in 111 individuals with type 2 diabetes in a community-based, cross-sectional study. We photodocumented retinal status and used HPLC to measure plasma carotenoid concentrations. Data for clinical and demographic variables and risk factors for diabetic retinopathy were obtained from 24 h urine and fasting blood samples, and an interviewer-assisted lifestyle questionnaire. We found that the combined lycopene and lutein/zeaxanthin (non-pro-vitamin A (non-PVA) carotenoid) concentration when compared with the pro-vitamin A (PVA) carotenoids (alpha-carotene, beta-carotene and beta-cryptoxanthin) was significantly lower in the retinopathy than non-retinopathy group (OR 1.2 (95 % CI 1.0, 1.4) v. 1.6 (95 % CI 1.4, 1.7), respectively; P = 0.009). A higher non-PVA:PVA ratio also predicted a lower risk of diabetic retinopathy, after adjustment for potential confounders (OR 0.33 (95 % CI 0.12, 0.95); P = 0.039). Finally, a higher concentration of PVA carotenoids was associated with greater odds of diabetic retinopathy, after adjustment for risk factors (P = 0.049). We suggest synergies between carotenoids are implicated in diabetic retinopathy, independent of established risk factors. Importantly, our observations indicate dietary modulation of retinopathy risk may be possible by increasing intakes of lutein- and lycopene-rich foods.

PMID: 18554424 [PubMed - as supplied by publisher]

13: J Agric Food Chem. 2008 Jun 11;56(11):4198-204. Epub 2008 May 14.
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Carbon and hydrogen stable isotope ratios of carotenoids and beta-carotene-based dietary supplements.

Kroll H, Friedrich J, Menzel M, Schreier P.

Lehrstuhl fur Lebensmittelchemie, Universitat Wurzburg, Wurzburg, Germany.

Considering the increasing nutritional and commercial importance of carotenoids, there is an interest in developing a reliable method for authenticity assessment of these compounds. Applying isotope ratio mass spectrometry using elemental analysis in the "combustion" (C) and "pyrolysis" (P) modes (EA-C/P-IRMS), the delta (13)C V-PDB and delta (2)H V-SMOW values of selected carotenoids and alpha/beta-carotene-based commercial dietary supplements were determined in comparison to those of synthetic and "natural" references. The delta (13)C V-PDB and delta (2)H V-SMOW values of synthetic beta-carotene samples ( n = 4), ranging from -25.3 per thousand to -26.4 per thousand and from -144 per thousand to -155 per thousand, respectively, differed clearly from the data determined for carotenoids from various natural sources, including C 3 plant material ( n = 9; delta (13)C V-PDB ranging from -28.5 per thousand to -32.8 per thousand and delta (2)H V-SMOW from -180 per thousand to -275 per thousand) and microalgae Dunaliella salina ( n = 1; delta (13)C V-PDB value of -15.6 per thousand and delta (2)H V-SMOW value of -191 per thousand). From five commercial dietary supplements under study, two revealed delta (13)C V-PDB and delta (2)H V-SMOW values in areas as found for synthetic references, and the other three had values near those of biotechnological beta-carotene produced by D. salina. The delta (13)C V-PDB and delta (2)H V-SMOW values recorded for natural lycopene ( n = 4) and lutein ( n = 5) ranged from -31.1 per thousand to -31.8 per thousand and from -180 to -201 per thousand, as well as from -28.8 per thousand to -32.2 per thousand and from -186 per thousand to -245 per thousand, respectively. Synthetic canthaxanthin ( n = 3) exhibited delta (13)C V-PDB and delta (2)H V-SMOW values ranging from -25.0 per thousand to -28.6 per thousand and from -133 per thousand to -153 per thousand, respectively. The EA-C/P-IRMS application of this study showed that the natural stable isotopic composition of carotenoids is a powerful tool for determining their origin.

PMID: 18476701 [PubMed - in process]

14: Br J Nutr. 2008 Jun;99(6):1293-300. Epub 2007 Nov 21.
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Long-term strict raw food diet is associated with favourable plasma beta-carotene and low plasma lycopene concentrations in Germans.

Garcia AL, Koebnick C, Dagnelie PC, Strassner C, Elmadfa I, Katz N, Leitzmann C, Hoffmann I.

Institute of Nutritional Science, University of Giessen, Giessen, Germany.

Dietary carotenoids are associated with a reduced risk of chronic diseases. Raw food diets are predominantly plant-based diets that are practised with the intention of preventing chronic diseases by virtue of their high content of beneficial nutritive substances such as carotenoids. However, the benefit of a long-term adherence to these diets is controversial since little is known about their adequacy. Therefore, we investigated vitamin A and carotenoid status and related food sources in raw food diet adherents in Germany. Dietary vitamin A, carotenoid intake, plasma retinol and plasma carotenoids were determined in 198 (ninety-two male and 106 female) strict raw food diet adherents in a cross-sectional study. Raw food diet adherents consumed on average 95 weight% of their total food intake as raw food (approximately 1800 g/d), mainly fruits. Raw food diet adherents had an intake of 1301 retinol activity equivalents/d and 16.7 mg/d carotenoids. Plasma vitamin A status was normal in 82% of the subjects (> or = 1.05 micromol/l) and 63% had beta-carotene concentrations associated with chronic disease prevention (> or = 0.88 micromol/l). In 77% of subjects the lycopene status was below the reference values for average healthy populations (< 0.45 micromol/l). Fat contained in fruits, vegetables and nuts and oil consumption was a significant dietary determinant of plasma carotenoid concentrations (beta-carotene r 0.284; P < 0.05; lycopene r 0.168; P = 0.024). Long-term raw food diet adherents showed normal vitamin A status and achieve favourable plasma beta-carotene concentrations as recommended for chronic disease prevention, but showed low plasma lycopene levels. Plasma carotenoids in raw food adherents are predicted mainly by fat intake.

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PMID: 18028575 [PubMed - indexed for MEDLINE]

15: J Chromatogr A. 2008 May 23;1192(1):191-3. Epub 2008 Apr 8.
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Isolation of all-trans lycopene by high-speed counter-current chromatography using a temperature-controlled solvent system.

Baldermann S, Ropeter K, Köhler N, Fleischmann P.

Institute of Food Chemistry, Technische Universität Braunschweig, Schleinitzstrasse 20, 38106 Braunschweig, Germany.

The effect of solvent system, partition coefficient, retention of stationary phase, column, revolution speed, and flow rate of mobile phase are well known parameters to effect HSCCC (high-speed counter-current chromatography) separations. Temperature effects on chromatographic techniques like HPLC and GC are well studied, but the influence of temperature on CCC solvent systems is hardly investigated. This paper presents the influence of temperature on several key parameters (partition coefficient, settling time, volume ratios) in the hydrophobic HSCCC solvent system hexane:dichloromethane:acetonitrile (30:11:18, v/v/v) used for the isolation of lycopene from tomato paste at 10, 15, 20 and 25 degrees C.

PMID: 18423656 [PubMed - indexed for MEDLINE]

16: Am J Cardiol. 2008 May 22;101(10A):50D-57D.
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The chemistry of novel xanthophyll carotenoids.

Jackson H, Braun CL, Ernst H.

Cardax Pharmaceuticals, 99-193 Aeia Heights Drive, Aiea, HI 96701, USA.

Natural product isolates are typically not developed as drug candidates because of the difficulty in obtaining the desired stable molecular orientation (ie, stereochemistry), purity, and scale required to meet pharmaceutical industry standards. Recent advances in medicinal and process chemistry have played key roles in transforming a class of dietary natural products-carotenoids-into potential medical therapeutics. Carotenoids are natural pigments derived from the acyclic C40 isoprenoid lycopene, which can also be classified as a tetraterpene. Carotenoids are classified on their chemical composition as either carotenes or xanthophylls. There are 5 C40 carotenoids manufactured synthetically on an industrial scale, including lycopene, ss,ss-carotene, and canthaxanthin (which are achiral compounds); zeaxanthin (produced in enantiopure form, as the 3R,3'R enantiomer); and astaxanthin (produced as mixture of configurational isomers) for use as nutritional supplements and for animal feed additives in poultry farming and aquaculture that are essential for the animals' growth, health and reproduction. The xanthophyll astaxanthin shows pharmaceutical potential, but the configurational complexity has thus far made it difficult to synthesize an enantiopure form on a large scale. Astaxanthin has 2 identical asymmetric carbon atoms (position 3 and 3') and can therefore exist in 4 different configurations, providing 3 different configurational isomers: (3S,3'S) and (3R,3'R), which are enantiomers, and (3R,3'S) and (3S,3'R), which are identical (a meso form). An enantiopure industrial scale synthesis of astaxanthin (3S,3'S) has recently been developed by BASF AG. The desired stereochemistry (chirality) is introduced early in the synthetic process by a proprietary catalytic reaction using an intermediate of the existing technical astaxanthin production process as a substrate. By controlling this essential process, it is possible to produce pharmaceutical quality astaxanthin in quantities large enough to support drug development programs for medical therapies.

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PMID: 18474275 [PubMed - indexed for MEDLINE]

17: Am J Cardiol. 2008 May 22;101(10A):20D-29D.
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Biologic activity of carotenoids related to distinct membrane physicochemical interactions.

McNulty H, Jacob RF, Mason RP.

Elucida Research, Beverly, MA 01915, USA.

Carotenoids are naturally occurring organic pigments that are believed to have therapeutic benefit in treating cardiovascular disease (CVD) because of their antioxidant properties. However, prospective randomized trials have failed to demonstrate a consistent benefit for the carotenoid beta-carotene in patients at risk for CVD. The basis for this apparent paradox is not well understood but may be attributed to the distinct antioxidant properties of various carotenoids resulting from their structure-dependent physicochemical interactions with biologic membranes. To test this hypothesis, we measured the effects of astaxanthin, zeaxanthin, lutein, beta-carotene, and lycopene on lipid peroxidation using model membranes enriched with polyunsaturated fatty acids. The correlative effects of these compounds on membrane structure were determined using small-angle x-ray diffraction approaches. The nonpolar carotenoids, lycopene and beta-carotene, disordered the membrane bilayer and stimulated membrane lipid peroxidation (>85% increase in lipid hydroperoxide levels), whereas astaxanthin (a polar carotenoid) preserved membrane structure and exhibited significant antioxidant activity (>40% decrease in lipid hydroperoxide levels). These results suggest that the antioxidant potential of carotenoids is dependent on their distinct membrane lipid interactions. This relation of structure and function may explain the differences in biologic activity reported for various carotenoids, with important therapeutic implications.

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PMID: 18474269 [PubMed - indexed for MEDLINE]

18: Bioresour Technol. 2008 May 20. [Epub ahead of print]
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Enhancement of carotenoids by mutation and stress induced carotenogenic genes in Haematococcus pluvialis mutants.

Sandesh Kamath B, Vidhyavathi R, Sarada R, Ravishankar GA.

Plant Cell Biotechnology Department, Central Food Technological Research Institute, KRS Road, Mysore 570 020, India.

Growing culture of green alga Haematococcus was exposed to mutagens such as UV, ethyl methane sulphonate (EMS) and 1-methyl 3-nitro 1-nitrosoguanidine (NTG), and further screened over herbicide - glufosinate. The survival rate of cells decreased with increasing concentration of mutagens and herbicides. The mutants exhibited 23-59% increase in total carotenoid and astaxanthin contents. The NTG treated glufosinate resistant mutant showed increased (2.2% to 3.8% w/w) astaxanthin content. The transcript levels of phytoene synthase, phytoene desaturase, lycopene cyclase, beta-carotene ketolase and beta -carotene hydroxylase enzymes in the mutant cultures were found to be 13-18, 14-17, 3, 3-22 and 6-20 fold higher respectively compared to wild type. The mutant obtained by UV irradiation showed highest lycopene cyclase activity (458 nmole beta -carotene formed/mg protein/h) followed by NTG mutant (315 nmole beta -carotene formed/mg protein/h) when compared to that of parent strain (105 nmole beta -carotene formed/mg protein/h). Expression analysis of carotenoid biosynthetic genes in the mutants exhibited increase in transcript levels compared to wild type.

PMID: 18499448 [PubMed - as supplied by publisher]

19: J Biotechnol. 2008 May 20;135(1):78-84. Epub 2008 Mar 18.
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Carotenoid accumulation in bacteria with enhanced supply of isoprenoid precursors by upregulation of exogenous or endogenous pathways.

Rodríguez-Villalón A, Pérez-Gil J, Rodríguez-Concepción M.

Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Av. Diagonal 645, 08028 Barcelona, Spain.

Carotenoids are isoprenoid pigments of industrial and nutritional interest. Although they are produced in non-carotenogenic Escherichia coli engineered with the appropriate biosynthetic genes, only a limited pool of their metabolic precursors is available in these bacteria. We have compared the production of carotenoids (lycopene) in strains in which the supply of precursors was enhanced either by upregulating the endogenous pathway via overexpression of deoxyxylulose 5-phosphate synthase (DXS) or by incorporating an exogenous MVA+ operon. In strains expressing DXS under the control of a leaky IPTG-inducible promoter, lycopene accumulation was increased up to 8-fold in the absence of inducer. Addition of IPTG, however, negatively affected lycopene production. Although induction of too high levels of the MVA+ operon enzymes also appeared to cause interference with cell metabolism, supplementation with mevalonate (to be metabolized into carotenoid precursors) resulted in a 10-fold increase in lycopene levels in cells with a near wild-type background. An additional 2-fold increase (up to 228mg/l) was obtained using an engineered BL21 strain. These results confirm that the MVA+ pathway is most convenient to upregulate the production of carotenoids (lycopene) production in E. coli but that factors other than precursor supply should be considered for high pigment accumulation levels.

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PMID: 18417238 [PubMed - in process]

20: Bioresour Technol. 2008 May;99(8):3166-73. Epub 2007 Jul 16.
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Use of metabolic stimulators and inhibitors for enhanced production of beta-carotene and lycopene by Blakeslea trispora NRRL 2895 and 2896.

Choudhari SM, Ananthanarayan L, Singhal RS.

Food Engineering and Technology Department, Institute of Chemical Technology, University of Mumbai, Matunga, Mumbai 400 019, India. <>

This work investigates the potential of metabolic stimulators, firstly to enhance the production of beta-carotene, and later use of inhibitors of lycopene cyclase so as to accumulate lycopene in the fermentation medium. Various non-ionic surfactants, natural oils, stimulators such as amino-acids, tricarboxylic acid cycle (TCA) intermediates, vitamin A and antibiotics were investigated for improved production of beta-carotene using the zygomycete fungus Blakeslea trispora. Span 20 at 0.2% increased the beta-carotene production from 139 mg/l to 318 mg/l. Examination of the mycelial morphology of the B. trispora with span 20 showed a shorter mycelial length, which allowed a well-dispersed growth of B. trispora. Supplementation of the medium with 1000 ppm vitamin A acetate gave highest concentration of beta-carotene (830+/-6 mg/l). Several chemical inhibitors such as imidazole, pyridine, triethylamine, piperidine, and nicotinic acid were then evaluated to block the biosynthesis at lycopene. Piperidine at 500 ppm gave a 7.76-fold improvement, and produced high titers of lycopene (775+/-5 mg/l) in a medium supplemented with vitamin A acetate.

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PMID: 17637505 [PubMed - indexed for MEDLINE]

21: BJU Int. 2008 May;101(10):1227-31. Epub 2008 Jan 24.
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Dietary modification in patients with prostate cancer on active surveillance: a randomized, multicentre feasibility study.

Parsons JK, Newman VA, Mohler JL, Pierce JP, Flatt S, Marshall J.

Moores Comprehensive Cancer Center, University of California San Diego, La Jolla, CA 21287, USA.

OBJECTIVES: To evaluate the feasibility of implementing a diet-based intervention in men with prostate cancer on active surveillance, as changes in diet might potentially inhibit the progression of prostate cancer. PATIENTS AND METHODS: As part of the Men's Eating and Living (MEAL) Study (a multicentre pilot trial of a diet-based intervention for prostate cancer) 43 men aged 50-80 years with prostate cancer and on active surveillance were randomized to receive either telephone-based dietary counselling or standardized, written nutritional information. Telephone counselling targets included increased intakes of vegetables (particularly cruciferous vegetables and tomato products), whole grains, and beans/legumes. Dietary intakes and plasma carotenoid levels were assessed at baseline and at after 6 months. RESULTS: In the intervention arm the mean daily intakes of total vegetables, crucifers and tomato products increased by 71%, 180% and 265%, respectively (P < 0.05); in the control arm there were no significant changes in mean intakes of these components. Similarly, in the intervention arm, mean plasma levels of alpha-carotene, beta-carotene, lutein, lycopene and total carotenoids increased by 37%, 32%, 23%, 30% and 25%, respectively (P < 0.05); in the control arm there were no significant changes in plasma levels of these components. There were no significant changes in either group in whole grain, beans/legumes, or fat intake. CONCLUSIONS: Telephone-based dietary counselling increases vegetable intake and plasma concentrations of potentially anticarcinogenic carotenoids in men with prostate cancer on active surveillance. These data support the feasibility of implementing clinical trials of diet-based interventions in this population.

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PMID: 18218061 [PubMed - indexed for MEDLINE]

22: Carcinogenesis. 2008 May;29(5):1042-8. Epub 2008 Mar 13.
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Plasma levels of carotenoids, retinol and tocopherol and the risk of gastric cancer in Japan: a nested case-control study.

Persson C, Sasazuki S, Inoue M, Kurahashi N, Iwasaki M, Miura T, Ye W, Tsugane S; JPHC Study Group.Collaborators (100)
Sobue T, Hanaoka T, Ogata J, Baba S, Mannami T, Okayama A, Kokubo Y, Miyakawa K, Saito F, Koizumi A, Sano Y, Hashimoto I, Ikuta T, Miyajima Y, Suzuki N, Nagasawa S, Furusugi Y, Nagai N, Sanada H, Hatayama Y, Kobayashi F, Uchino H, Shirai Y, Kondo T, Sasaki R, Watanabe Y, Miyagawa Y, Kobayashi Y, Kishimoto Y, Takara E, Fukuyama T, Kinjo M, Irei M, Sakiyama H, Imoto K, Yazawa H, Seo T, Seiko A, Ito F, Shoji F, Murata A, Minato K, Motegi K, Fujieda T, Matsui K, Abe T, Katagiri M, Suzuki M, Doi M, Terao A, Ishikawa Y, Tagami T, Sueta H, Doi H, Urata M, Okamoto N, Ide F, Sakiyama H, Onga N, Takaesu H, Uehara M, Horii F, Asano I, Yamaguchi H, Aoki K, Maruyama S, Ichii M, Takano M, Tsubono Y, Suzuki K, Honda Y, Yamagishi K, Sakurai S, Kabuto M, Yamaguchi M, Matsumura Y, Sasaki S, Watanabe S, Akabane M, Kadowaki T, Noda M, Kawaguchi Y, Takashima Y, Nakamura K, Matsushima S, Natsukawa S, Shimizu H, Sugimura H, Tominaga S, Iso H, Iida M, Ajiki W, Ioka A, Sato S, Maruyama E, Konishi M, Okada K, Saito I, Yasuda N, Kono S.
Epidemiology and Prevention Division, Research Center for Cancer Prevention and Screening, National Cancer Center, 5-1-1 Tsukiji, Chuo-ku 104-0045, Tokyo, Japan.

Fruits and vegetables have been suggested to confer protection against diseases such as cancer through the effects of antioxidants, often represented by carotenoids. We investigated the impact of carotenoids, retinol and tocopherol on gastric cancer development in a large nested case-control study among Japanese with known Helicobacter pylori infection status. A total of 36 745 subjects aged 40-69 in the Japan Public Health Center-based Prospective Study who responded to the baseline questionnaire and provided blood samples in 1990-1995 were followed until 2004. Plasma levels of carotenoids in 511 gastric cancer cases and 511 matched controls were measured by high-performance liquid chromatography. Odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were estimated using conditional logistic regression models. Plasma level of beta-carotene was inversely associated with the risk of gastric cancer (compared with the lowest quartile: OR = 0.63, 95% CI = 0.31-0.75; OR = 0.48, 95% CI = 0.31-0.75 and OR = 0.46, 95% CI = 0.28-0.75, for quartile 2, 3 and 4, respectively, P(trend) < 0.01). Inverse associations were evident in men for alpha-carotene (P(trend) = 0.04) and beta-carotene (P(trend) < 0.01), but not in women, who had relatively higher plasma levels compared with men. We found no statistically significant association between plasma levels of lutein/zeaxanthin, lycopene, retinol, alpha- or gamma-tocopherol and gastric cancer risk. Our findings suggest that those who have very low plasma levels of alpha-carotene and beta-carotene are at a higher risk of gastric cancer.

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PMID: 18339681 [PubMed - in process]

23: J Phys Chem B. 2008 May 1;112(17):5449-57. Epub 2008 Apr 8.
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Pulsed electron nuclear double resonance studies of carotenoid oxidation in Cu(II)-substituted MCM-41 molecular sieves.

Lawrence J, Focsan AL, Konovalova TA, Molnar P, Deli J, Bowman MK, Kispert LD.

Department of Chemistry, The University of Alabama, Box 870336, Tuscaloosa, Alabama 35487, USA.

Carotenoid (Car) radical intermediates formed upon catalytic or photooxidation of lutein (I), 7'-apo-7',7'-dicyano-beta-carotene (II), and lycopene (III) inside Cu(II)-MCM-41 molecular sieves were studied by pulsed electron nuclear double resonance (ENDOR) spectroscopies. The Davies and Mims ENDOR spectra (15-20 K) were simulated using the hyperfine coupling constants predicted by density functional theory (DFT) calculations. The DFT calculations revealed that upon chemical oxidation, carotenoid radical cations (Car*+) are formed, whereas carotenoid neutral radicals (#Car*) are produced by proton loss (indicated by #) from the radical cation. This loss is to first order independent of polarity or hydrogen bonding for carotenoids I, II, or III inside Cu(II)-MCM-41 molecular sieves.

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PMID: 18393549 [PubMed - indexed for MEDLINE]

24: Nutr Rev. 2008 May;66(5):237-49.
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Nutrition and gastric cancer risk: an update.

Liu C, Russell RM.

Jean Mayer United States Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts, USA.

Data from epidemiologic, experimental, and animal studies indicate that diet plays an important role in the etiology of gastric cancer. High intake of fresh fruits and vegetables, lycopene and lycopene-containing food products, and potentially vitamin C and selenium may reduce the risk for gastric cancer. Data also suggest that high intake of nitrosamines, processed meat products, salt and salted foods, and overweight and obesity are associated with increased risk for gastric cancer. However, current data provide little support for an association of beta-carotene, vitamin E, and alcohol consumption with risk for gastric cancer.

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PMID: 18454810 [PubMed - indexed for MEDLINE]

25: Wei Sheng Yan Jiu. 2008 May;37(3):311-3.
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[Effects of coenzyme Q10 or combined with micronutrients on antioxidant defense system in rats]

[Article in Chinese]

Wang H, Zhao X, Yin S.

Institute for Nutrition and Food Safety, Chinese Center for Disease Control and Prevention, Beijing 100050, China.

Objective: In order to evaluate the effect of coenzyme Q10 (CQ) or combined with carotenoids (lycopene and lutein, LL) or/and mineral nutrients (zinc and selenium, ZS) on the antioxidant defense system, The rats were randomized into 6 groups: control, CQ [CQ 10 mg/(kg x d)], CQ+ ZS[CQ 10 mg/(kg x d), Zn 1 mg/(kg x d), Se 4 microg/(kg x d)], CQ+ LL [CQ 10 mg/(kg x d), Lutein 1 mg/(kg x d), Lycopene 2 mg/(kg x d)], CQ + ZS + LL [CQ 10 mg/(kg x d), Zn 1 mg/(kg x d), Se 4 microg/(kg x d), Lutein 1 mg/(kg x d), Lycopene 2 mg/(kg x d)] and VE [VE 2 mg/(kg x d)], and then fed with a diet based on AIN-76 rodent diet but containing 4% lard as well as 4% corn oil. The supplement were given by oral for 8 weeks, and the plasma and liver antioxidant enzymes activity, malondialdehyde levels and lymphocyte DNA damage were determined. The results showed that the groups treated with CQ had a higher plasma SOD and TOAC level and liver SOD and GPX activity than those of the control group. Combination treatments further enhanced antioxidant enzymes activity and reduced MDA levels & DNA damage. Most of the parameters had reached statistical significance in comparison with the control. These findings suggested that CQ exerted antioxidative effects in rats, and when it was supplemented in combination with other antioxidants, the effects were raised to some extent.

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PMID: 18646530 [PubMed - in process]

26: J Biol Chem. 2008 Apr 25;283(17):11364-73. Epub 2008 Feb 19.
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The carotenoid cleavage dioxygenase 1 enzyme has broad substrate specificity, cleaving multiple carotenoids at two different bond positions.

Vogel JT, Tan BC, McCarty DR, Klee HJ.

Horticultural Sciences Department and the Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, Florida 32611, USA.

In many organisms, various enzymes mediate site-specific carotenoid cleavage to generate biologically active apocarotenoids. These carotenoid-derived products include provitamin A, hormones, and flavor and fragrance molecules. In plants, the CCD1 enzyme cleaves carotenoids at 9,10 (9',10') bonds to generate multiple apocarotenoid products. Here we systematically analyzed volatile apocarotenoids generated by maize CCD1 (ZmCCD1) from multiple carotenoid substrates. ZmCCD1 did not cleave geranylgeranyl diphosphate or phytoene but did cleave other linear and cyclic carotenoids, producing volatiles derived from 9,10 (9',10') bond cleavage. Additionally the Arabidopsis, maize, and tomato CCD1 enzymes all cleaved lycopene to generate 6-methyl-5-hepten-2-one. 6-Methyl-5-hepten-2-one, an important flavor volatile in tomato, was produced by cleavage of the 5,6 or 5',6' bond positions of lycopene but not geranylgeranyl diphosphate, zeta-carotene, or phytoene. In vitro, ZmCCD1 cleaved linear and cyclic carotenoids with equal efficiency. Based on the pattern of apocarotenoid volatiles produced, we propose that CCD1 recognizes its cleavage site based on the saturation status between carbons 7 and 8 (7' and 8') and carbons 11 and 12 (11' and 12') as well as the methyl groups on carbons 5, 9, and 13 (5', 9', and 13').

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PMID: 18285342 [PubMed - indexed for MEDLINE]

27: Invest Ophthalmol Vis Sci. 2008 Apr 17. [Epub ahead of print]
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Blood levels of vitamin C, carotenoids and retinol are inversely associated with cataract in a north Indian population.

Dherani MK, Murthy GV, Gupta SK, Young I, Maraini G, Camparini M, Price GM, John N, Chakravarthy U, Fletcher A.

Department of Epidemiology & Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom.

Purpose: To examine the association of blood antioxidants with cataract. Methods: Cross-sectional study of people aged 50 and over identified from household enumeration of 11 randomly sampled villages in North India. Participants were interviewed for putative risk factors (tobacco, alcohol, biomass fuel use, sunlight exposure, socio- economic status) and underwent lens photography and blood sampling. Lens photographs (nuclear, cortical and posterior subcapsular) were graded using the Lens Opacities Classification System (LOCS II). Cataract was defined as LOCS II grade >/=2 for any opacity or ungradeable due to dense opacification or a history of cataract surgery; people without cataract were defined as LOCS II 2 on all three types of opacity and absence of previous surgery. Results: Of 1443 people aged 50 years or above, 94% were interviewed, 87 % attended an eye examination and 78% gave a blood sample; 1112 (77%) were included in analyses. Compared to western populations, antioxidants were low, especially vitamin C. Vitamin C was inversely associated with cataract. Odds ratios (OR) for the highest (>== 15 micromol/l) compared to the lowest (6.3 micromol/L) tertile were 0.64, (95% Confidence Interval (CI) 0.48 - 0.85), p 0.01. Tertiles of zeaxanthin, p 0.03,alpha carotene p 0.05, and retinol p 0.02,were associated with decreased odds of cataract in categorical analysis. In analysis of continuous data significant inverse associations were found for vitamin C, zeaxanthin, lutein, lycopene, alpha and beta carotene, beta-cryptoxanthin but not for alphaor gamma tocopherol. Conclusions: We found inverse associations with cataract and blood antioxidants in an antioxidant-depleted population.

PMID: 18421094 [PubMed - as supplied by publisher]

28: Int J Food Sci Nutr. 2008 Apr 10:1-16. [Epub ahead of print]
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Tangerine tomatoes increase total and tetra-cis-lycopene isomer concentrations more than red tomatoes in healthy adult humans.

Burri BJ, Chapman MH, Neidlinger TR, Seo JS, Ishida BK.

Western Human Nutrition Research Center, USDA, ARS, PWA, Davis, California, USA.

Lycopene, or the foods that contain it, may prevent prostate cancer. Studies suggest that some cis-lycopene isomers are more bioavailable than the trans-lycopene isomer. We hypothesized that tangerine tomatoes, which predominantly contain the tetra-cis isomer, should be a good source of bioavailable lycopene. We fed lunches containing 300 g tangerine or red tomato sauce per day to 21 healthy adults in a double-blind crossover design. We collected blood at baseline and after each treatment and washout period. We measured tetra-cis, other cis, and trans lycopene, as well as other carotenoids, by reversed-phase high-performance liquid chromatography. Both tomato sauces increased lycopene concentrations in blood, but the tangerine tomato sauce caused a greater increase of total and tetra-cis-lycopene. The cis isomer(s) may also have facilitated absorption of the trans-lycopene isomer. Indices of oxidative damage decreased as serum lycopene concentrations increased. Our results suggest that total lycopene concentrations can be increased by substituting tetra-cis-lycopene-rich tangerine tomatoes for common red tomatoes in the diet.

PMID: 18608554 [PubMed - as supplied by publisher]

29: Colorectal Dis. 2008 Apr 9. [Epub ahead of print]
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Free radical activity and lipid soluble anti-oxidant vitamin status in patients with long-term ileal pouch-anal anastomosis.

El Muhtaseb MS, Talwar D, Duncan A, O'reilly DS, McKee RF, Anderson JH, Foulis A, Finlay IG.

Department of Coloproctology, Lister Department of Surgery, Glasgow Royal Infirmary, Glasgow, UK.

Objective Ileal pouch-anal anastomosis (IPAA) is the operation of choice for patients with ulcerative colitis. Free radical activity and the status of lipid soluble antioxidant vitamins have not been previously assessed in patients with IPAA. The aim of the present study was to measure the plasma concentrations of lipophyllic antioxidants and free radical activity in IPAA patients and compare them with normal subjects. Method Forty-eight IPAA patients and 50 healthy controls were studied. A dietary assessment of vitamin E (alpha-tocopherol) and carotene was undertaken and plasma antioxidant status was assessed. Plasma malondialdehyde (MDA) was measured to assess the extent of free radical damage. In IPAA patients, association between the degree of inflammation in the pouch mucosa and the plasma concentration of lipophyllic antioxidants and extent of free radical activity was investigated. Results The dietary intake of carotene was similar in both groups. Intake of vitamin E was significantly lower in patients than controls (P = 0.01). In the IPAA group plasma concentrations of alpha-carotene, beta-carotene and lycopene were significantly lower (P < 0.001) and alpha-tocopherol:cholesterol ratio significantly higher (P < 0.001). Free radical damage was significantly greater in patients than controls (P < 0.01). There were no significant correlations between the degree of inflammation in the pouch and plasma concentrations of MDA, carotenoids, alpha-tocopherol:cholesterol ratio or intake of vitamins. Conclusion Compared with normal subjects, patients with IPAA have significantly lower plasma concentrations of lipophyllic antioxidants alpha-carotene, beta-carotene and lycopene and higher free radical activity suggesting increased oxidative stress. These differences do not appear to be related to diet and do not correlate with histological severity of pouch inflammation.

PMID: 18400037 [PubMed - as supplied by publisher]

30: Am J Clin Nutr. 2008 Apr;87(4):1009-18.
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Selected antioxidants and risk of hormone receptor-defined invasive breast cancers among postmenopausal women in the Women's Health Initiative Observational Study.

Cui Y, Shikany JM, Liu S, Shagufta Y, Rohan TE.

Office of Health Assessment and Epidemiology, Los Angeles County Department of Public Health, Los Angeles, CA 90012, USA.

BACKGROUND: Few studies have evaluated carotenoids and vitamins C and E in association with the risk of breast cancers defined by estrogen receptor (ER) and progesterone receptor (PR) status. OBJECTIVE: We examined the associations between dietary and supplemental intakes of these nutrients and risk of breast cancers jointly defined by both ER and PR status among postmenopausal women. DESIGN: Our investigation was conducted in the Women's Health Initiative Observational Study. After following 84 805 women for an average of 7.6 y, 2879 incident invasive breast cancer cases had been ascertained, of whom 2509 had receptor data. We used Cox proportional hazards models to assess the associations of interest. RESULTS: Dietary alpha-carotene (highest versus lowest quintile: RR = 0.83; 95% CL = 0.70, 0.99; P for trend = 0.019), beta-carotene (highest versus lowest quintile: RR = 0.78; 95% CL = 0.66, 0.94; P for trend = 0.021), and lycopene (highest versus lowest quintile: RR = 0.85; 95% CL = 0.73, 1.00; P for trend = 0.064) were inversely associated with risk of ER+PR+breast cancer, but not with other breast cancer groups jointly defined by ER and PR status. Total or supplemental beta-carotene and dietary intakes of lutein+zeaxanthin and beta-cryptoxanthin were not associated with breast cancers defined by ER and PR status. Vitamin E (regardless of source) and dietary vitamin C were not associated with breast cancer. However, total and supplemental vitamin C intake had weak positive associations with breast cancer overall. CONCLUSION: Dietary intake of certain carotenoids might be differentially associated with risk of invasive breast cancers jointly defined by ER and PR status among postmenopausal women.

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PMID: 18400726 [PubMed - indexed for MEDLINE]

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