On the other hand, lycopene occurs in watermelons, tomatoes, guavas, and grapefruit. All carotenes reduce the risk of lung cancer. Carotenoid is a tetraterpenoid, an organic pigment only produced by photosynthetic organisms including plants, algae, and bacteria.
It gives a bright red, orange or yellow color to fruits and vegetables. Generally, carotenoids serve as accessory pigments involved in photosynthesis. However, animals cannot synthesize carotenoids inside their body. However, these compounds play an important function in the body. They serve as antioxidants, which can deactivate free radicals.
Therefore, they have strong cancer-fighting properties. In addition, carotenoids have anti-inflammatory effects and some immune functions, which help to reduce the risk of cardiovascular disease. Figure 2: Egg Yolk with Lutein and Zeaxanthin. Furthermore, the two main categories of carotenoids are carotenes and xanthophylls. The main difference between carotene and xanthophyll is that carotene does not contain oxygen atoms in its structure while xanthophyll contains an oxygen atom.
Additionally, they absorb and emit light in different wavelengths. Therefore, carotene gives a red to orange color while xanthophyll mainly gives a yellow color. When considering xanthophylls, lutein and zeaxanthin are the two types responsible for the yellow color of the macula lutea or the yellow spot in the retina of the human eye. Lutein also preferentially accumulates in the brain , Recent studies suggested that lutein and zeaxanthin concentrations in the macula were correlated with brain lutein and zeaxanthin status and might be used as a biomarker to assess cognitive health Additionally, in the Georgia Centenarian Study, the analysis of cross-sectional data from 47 centenarian decedents showed a positive association between post-mortem measures of brain lutein concentrations and pre-mortem measures of cognitive function Brain lutein concentrations were found to be significantly lower in individuals with mild cognitive impairment compared to those with normal cognitive function Most carotenoids in foods are found in the all-trans form see Figure 1 and Figure 2 above , although cooking may result in the formation of other isomers.
The relatively low bioavailability of carotenoids from most foods compared to supplements is partly due to the fact that they are associated with proteins in the plant matrix Chopping, homogenizing, and cooking disrupt the plant matrix, increasing the bioavailability of carotenoids 3. For example, the bioavailability of lycopene from tomatoes is substantially improved by heating tomatoes in oil , Lycopene gives tomatoes, pink grapefruit, watermelon, and guava their red color.
Lycopene is not a provitamin A carotenoid because it cannot be converted to retinol. Some foods that are good sources of lycopene are listed in Table 5 Although lutein and zeaxanthin are different compounds, they are both classified as xanthophylls and nonprovitamin A carotenoids see Figure 2 above.
Both pigments are present in a variety of fruit and vegetables. Dark green leafy vegetables like spinach and kale are particularly rich sources of lutein but poor sources of zeaxanthin Although relatively low in lutein, egg yolks and avocados are highly bioavailable sources of lutein.
Good sources of dietary zeaxanthin include yellow corn, orange pepper, orange juice, honeydew melon , and mango Some foods containing lutein and zeaxanthin are listed in Table 6 Dietary supplements providing purified carotenoids and combinations of carotenoids are commercially available in the US without a prescription. Carotenoids are best absorbed when taken with a meal containing fat.
Lycopene has no provitamin A activity. Synthetic lycopene and lycopene from natural sources, mainly tomatoes, are available as nutritional supplements containing up to 15 mg of lycopene per softgel capsule Lutein and zeaxanthin are not provitamin A carotenoids.
Lutein and zeaxanthin supplements are available as free carotenoids non-esterified or as esters esterified to fatty acids. Both forms appear to have comparable bioavailability Many commercially available lutein and zeaxanthin supplements have much higher amounts of lutein than zeaxanthin Supplements containing only lutein or zeaxanthin are also available.
Lycopenodermia : High intakes of lycopene-rich food or supplements may result in a deep orange discoloration of the skin known as lycopenodermia. Because lycopene is more intensely colored than the carotenes, lycopenodermia may occur at lower doses than carotenodermia 8. Adverse effects of lutein and zeaxanthin have not been reported There is no reason to limit the consumption of carotenoid-rich fruit and vegetables during pregnancy The cholesterol -lowering agents, cholestyramine Questran and colestipol Colestid , can reduce absorption of fat- soluble vitamins and carotenoids, as can mineral oil and Orlistat Xenical , a drug used to treat obesity Colchicine, a drug used to treat gout , can cause intestinal malabsorption.
A three-year randomized controlled trial in patients with documented coronary heart disease CHD and low serum high density lipoprotein HDL concentrations found that a combination of simvastatin Zocor and niacin increased HDL2 levels, inhibited the progression of coronary artery stenosis , and decreased the frequency of cardiovascular events, including myocardial infarction and stroke These contradictory findings indicate that further research is needed on potential interactions between antioxidant supplements and cholesterol-lowering agents, such as niacin and statins.
One study in adults found that those who consumed more than 4. However, advising people who use plant sterol- or stanol-containing margarines to consume an extra serving of carotenoid-rich fruit or vegetables daily prevented decreases in plasma carotenoid concentrations , The relationships between alcohol consumption and carotenoid metabolism are not well understood. Updated in December by: Jane Higdon, Ph. Updated in May by: Victoria J. Drake, Ph. Updated in July by: Barbara Delage, Ph.
Reviewed in August by: Elizabeth J. Johnson, Ph. Wang XD. Modern Nutrition in Health and Disease. Am J Clin Nutr. Dietary factors that affect the bioavailability of carotenoids. J Nutr. Priyadarshani AM. A review on factors influencing bioaccessibility and bioefficacy of carotenoids. Crit Rev Food Sci Nutr. Reboul E. Absorption of vitamin A and carotenoids by the enterocyte: focus on transport proteins. Provitamin a carotenoid bioavailability:what really matters?
Int J Vitam Nutr Res. Borel P. Genetic variations involved in interindividual variability in carotenoid status. Mol Nutr Food Res. Food and Nutrition Board, Institute of Medicine. Dietary reference intakes for vitamin C, vitamin E, selenium, and carotenoids. Washington, D.
National Academy Press. Weber D, Grune T. Free Radicals in Biology and Medicine. Lycopene as the most efficient biological carotenoid singlet oxygen quencher. Arch Biochem Biophys. Antioxidant and prooxidant properties of carotenoids. Kaulmann A, Bohn T. Carotenoids, inflammation, and oxidative stress--implications of cellular signaling pathways and relation to chronic disease prevention.
Nutr Res. Carotenoids activate the antioxidant response element transcription system. Mol Cancer Ther. Life Sci. Lian F, Wang XD. Int J Cancer. Lycopene inhibits cyclic strain-induced endothelin-1 expression through the suppression of reactive oxygen species generation and induction of heme oxygenase-1 in human umbilical vein endothelial cells. Clin Exp Pharmacol Physiol.
J Agric Food Chem. Biologic mechanisms of the protective role of lutein and zeaxanthin in the eye. Annu Rev Nutr. Supplementation with the carotenoids lutein or zeaxanthin improves human visual performance. Ophthalmic Physiol Opt. A week lutein supplementation improves visual function in Chinese people with long-term computer display light exposure. Br J Nutr. Macular pigment and visual performance under glare conditions. Optom Vis Sci. The effect of lutein supplementation on visual fatigue: a psychophysiological analysis.
Appl Ergon. Dietary lutein and zeaxanthin: possible effects on visual function. Nutr Rev. Bertram JS. Carotenoids and gene regulation. Biological activities of natural and synthetic carotenoids: induction of gap junctional communication and singlet oxygen quenching. Transcriptional regulation of connexin 43 expression by retinoids and carotenoids: similarities and differences. Mol Carcinog. J Lab Clin Med. Effects of lycopene and lutein supplementation on the expression of functionally associated surface molecules on blood monocytes from healthy male nonsmokers.
J Infect Dis. Prolonged tomato juice consumption has no effect on cell-mediated immunity of well-nourished elderly men and women. Eur J Clin Nutr. Centers for Disease Control and Prevention. Cancer among men. August 20, Cancer among women. Carotenoids and the risk of developing lung cancer: a systematic review. N Engl J Med. J Natl Cancer Inst. Lung cancer chemoprevention: a randomized, double-blind trial in Linxian, China.
Cancer Epidemiol Biomarkers Prev. Veeramachaneni S, Wang XD. Carotenoids and lung cancer prevention. Front Biosci Schol Ed. Moyer, V. Vitamin, mineral, and multivitamin supplements for the primary prevention of cardiovascular disease and cancer: U. Preventive services Task Force recommendation statement. Ann Intern Med. Giovannucci E. A review of epidemiologic studies of tomatoes, lycopene, and prostate cancer.
Exp Biol Med Maywood. The role of tomato products and lycopene in the prevention of prostate cancer: a meta-analysis of observational studies. Effect of carotene and lycopene on the risk of prostate cancer: a systematic review and dose-response meta-analysis of observational studies. PLoS One. Correction: effect of carotene and lycopene on the risk of prostate cancer: a systematic review and dose-response meta-analysis of observational studies.
Carotenoids, retinol, tocopherols, and prostate cancer risk: pooled analysis of 15 studies. A comprehensive review on the colorless carotenoids phytoene and phytofluene. Diet, nutrition, physical activity, and prostate cancer. A phase II randomized trial of lycopene-rich tomato extract among men with high-grade prostatic intraepithelial neoplasia. Nutr Cancer. A randomized double-blind placebo controlled phase I-II study on clinical and molecular effects of dietary supplements in men with precancerous prostatic lesions.
Hydrocarbons are carotenes, which we discussed above, and the oxygenated class includes xanthophylls. All these are colored pigments having orange, yellow and red colors. These pigments are found in plants, animals and micro organisms. They are also responsible for the biological coloration of animals and plants. Carotenoid pigments are important for photosynthesis too. They are in the light harvesting complexes, to help pants to obtain solar energy for the photosynthesis.
Carotenoids like lycopene are important for preventing cancers and heart diseases. Also, these are precursors for many compounds, which give fragrance and flavor. Carotenoid pigments are synthesized by plants, bacteria, fungi, and lower algae, whereas some animals obtain these through diet. All the carotenoid pigments have two six carbon rings at ends, which are connected by a chain of carbon and hydrogen atoms.
These are relatively non polar. As stated above carotene is non polar compared to xanthophylls. Xanthophylls contain oxygen atoms, which give them a polarity.
0コメント