Aarti Singh
a,
Sayeed Ahmad
b and
Anees Ahmad
*a
aDepartment of Chemistry, Aligarh Muslim University, Aligarh, UP, India. E-mail: as87822@gmail.com; Tel: +91-9536322688
bDepartment of Pharmacognosy and Phytochemistry, Jamia Hamdard, New Delhi, India
First published on 13th July 2015
This review covers and discusses various aspects of carotenoids including their chemistry, classification, biosynthesis, extraction methods (conventional and non-conventional), analytical techniques and biological roles in living beings. Carotenoids play a very crucial role in human health through foods, cosmetics, nutraceuticals and pharmaceuticals. Among carotenoids, lycopene acts as best antioxidant. Various extraction methods have been employed for extraction of carotenoids: solvent extraction, soxhlet extraction, centrifugation and non-conventional methods of extraction such as ultrasound-assisted, microwave-assisted, enzymatic and the innovative technique supercritical carbondioxide (SC-CO2) extraction. The green and environmentally friendly technique for extraction of carotenoids is SC-CO2 extraction which extracts pure compound in high yield without the use of harmful organic solvents, it operates at lower temperature so it is useful for extraction of thermolabile compounds. This technique uses SC-CO2 as green solvent and other solvents as modifiers which are generally recognized as safe (GRAS) solvents. Green technology is the need of present time in order to keep environment healthy, pollution free and sustainable for coming generation. Present review includes several analytical techniques used to identify and quantify carotenoids are: thin layer chromatography (TLC), high performance thin layer chromatography (HPTLC), high performance liquid chromatography (HPLC), liquid chromatography-mass spectrometry (LC-MS), nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR), ultra performance liquid chromatography-tandem mass spectrometer (UPLC-MS), UV-Vis (Ultraviolet-Visible) spectrophotometry; out of these, NMR and FTIR have been explored the least for carotenoid analysis.
Carotenoids | Dietary sources-μg per 100 grams | Function/effectsreferences | Market formulation available |
---|---|---|---|
α-Carotene | Pumpkin canned-28215, carrots-23851, vegetables mixed (corn, lima beans, peas, green beans, carrots)-14247, peas-7121, squash, cooked-5650, peppers, sweet, red-4414, peppers, hotchilli, red-4247, pumpkin, raw-3962, pumpkin, raw-3962 squash, raw-3707, pumpkin, cooked-3480, balsam-pear, raw-2176, collards, raw-1587, fiddlehead ferns, raw-1535, grape leaves, raw-1352, spices, chilli powder-1331, plantains, raw-718, tomatoes, green, raw-678, nopales, raw-600, chard Swiss, raw-474, kumquats, raw-437, coriander leaves, raw-313, pepper, banana, raw-289 | Provitamin A activity; antioxidant, lowers risk of lung cancer/immune-enhancement; stimulate cell to cell communication; decreases risk of some cancers17,245,250 | Alpha GPC capsules, Mcobacin |
β-Carotene | Green leafy vegetables and orange and yellow fruits and vegetables (carrots, apricots, spinach, sweet potatoes, pumpkin, pepper, kale, cantaloupe)/spices (paprika, cayenne, chili)-26162; sun dried chili peppers-14844; sweet potato chips-14205; sweet potato (baked)-11509; carrot juice-9303; kale-9226; kale (frozen, cooked)-8823; sweet potato-8509; carrots (cooked)-8332, carrots-8285, canned pumpkin-6940, mustard greens-6300, dark green leafy vegetables (spinach, cooked)-6288, mixed vegetables (canned)-5670, spinach-5626, lettuce-5226, parsley-5054, dried herbs (marjoram, sage, coriander)-4806, butternut squash (cooked)-4570, garden cress-4150, cilantro (coriander)-3930, collard greens-3842, Swiss chard-3647, Basil-3142, pumpkin-3100, cime di rapa (broccoli raab, cooked)-2720, chives-2612, thyme-2264, dried apricots-2163, cantaloupes-2020, watercress-1914 | Provitamin A activity; antioxidant/immune-enhancement; decreases risk of some cancers and some cardiovascular events; high-dose supplementation may increase the risk of lung cancer among smokers247,282,285,305 | Dietfold, Leroy Capsules, Lycovia, Lycoza, Pevit, Bel-3, UK-TOP, Avencare, Alpene, Nidze-LP, Fokus, Attovita plus, Alfabeta tablets, Lycozin, Ybeta-S, Mycopene, Nurorose-Red, B-Fact, Betavit-AFR, Multi-carotene, Lycolide-Red, Spirulina capsules |
Lycopene | Tomatoes-2937, water melon, apricot, peaches; sun dried tomatoes-45902, tomato puree-21754, rose hips-6800, guava-5204, watermelon-4532, tomatoes cooked-3041, papaya-1828, grapefruit-1135, sweet red peppers-484, dried herbs and spices (Basil)-393 | Antioxidant/decreases risk of some cancers and some cardiovascular events, dibetes, and osteoporosis17,290 | Lycomits, SAC, Telvit-18, ARIA-L, Algen, Lyrisel, Litecap soft gelatine capsules, L-TO, Lycobury, Lycofun, Lycoza, Lyco, Becogold, Lycosure-SG, Tricopen-Forte, Lycotone-XX, Lyene-G, Avit, Lyomuch, Litovit |
β-Cryptoxanthin | Peppers, sweet, red, cooked-16876, pumpkin, raw-16500, squash, cooked-15583, squash, raw-15429, pumpkin, cooked-14497, squash, frozen-5488, peppers, hot chilli, red-4714, peppers, sweet, red, frozen-3800, peppers, sweet, red, raw-3161, coriander leaves, raw-1756, carrots, canned-1252, carrots, frozen, cooked-1076, dandelion greens, raw-538, collards raw-538, cucumber, with peel, raw-347, cucumber, peeled, raw-300, corn, sweet, yellow, raw-267, peppers, hot chilli, green, raw-250, peppers, jalapeno, raw-227, chrysanthemum, garland, raw-200 | Provitamin A activity; anti-oxidant/anti-inflammatory effects; inhibits risks of some cancer and cardiovascular events; immune enhancement283,301 | |
Lutein/zeaxanthin | Dark green leafy vegetables (spinach, kale), red peppers, maize, tomatoes, corn, and egg yolks; kale, raw-39551, dandelion greens, raw-13609, spices, paprika-13158, turnips greens, raw-12824, cress, garden, raw-12499, spinach, raw-12197, chard, Swiss, raw-10999, chicory greens, raw-10301, mustard greens, raw-9899, collards, raw-8832, radicchio, raw-8832, watercress, raw-5767, Basil, fresh-5649, parsley, raw-5561, coriander leaf, dried-5529, parsley, dried-5529, peppers, sweet, green, freeze-dried-5198, celery flakes, dried-5076, chrysanthemum, garland, raw-3834, lambsquarters, raw-3616, arugula, raw-3555, spinach, dry-3487, peas, green, raw-2477, lettuce, cos or romaine, raw-2312, taro leaves, raw-1932, leeks, raw-1900, grape leaves, raw-1747, lettuce, green leaf, raw-1730 | Anti-photosensitizing agent and photosynthetic pigment; acts as antioxidants and blue light filters, antimutagenic & anticarcenogenic/decrease age-related macular degeneration, cataract, and risk of cardiovascular disease and certain cancers17,329,352 | FloraGLO®-lutein, Lycoark, Pevit, Avencare, Alpene, Nidze-LP, Lycozin, Mycopene, Lycolide-Red; OPTISHARP® (zeaxanthin), Swanson-ultra, Nordic Naturals Ultimate DHA Eye + Lutein & zeaxanthin, Pure encapsulations Lutein/Zeaxanthin, TruNature Vision Complex with Lutein & zeaxanthin, Best Naturals Lutein, Vitacost Lutein |
Astaxanthin | Green algae, salmon, trout, crustacean; salmonids-5, plankton-60, krill-120, arctic shrimp (P borealis)-1200, phaffia yeast-10000, Haematococcus pluvialis-40000 | Antioxidant; coloration/prevention certain cancers, cataract, diabetes, and inflammatory neurodegenerative and risk of cardiovascular disease and certain cancers285,342 | Lycotone-XX, Zenith Nutrition Astaxanthin, Healthy-Origins Astaxanthin, Nutrex BioAstin Hawaiian Astaxanthin, Neptune Krill Oil, Nutrex Hawaii BioAstin Natural Astaxanthin, Best Naturals-Astaxanthin, Now Foods Astaxanthin, Nutrigold Astaxanthin gold, MasoN natural Triple Strength Krill oil with Astaxanthin, Bluebonnet Astaxanthin |
Canthaxanthin | Salmon, crustacean, green algae, bacteria, fish (carp, golden mullet, seabream & trush wrasse) | Antioxidant; coloration/immune enhancement; decreases risk of some cancers17,300,301 | Bronze EZee, Orobronze |
Fucoxanthin | Brown algae, heterokonts | Antioxidants/anti-cancer, anti-allergic, anti-obese, anti-inflammatory, and anti-osteoporotic activities292,295,299 | Vitabase-Fucoxanthin Plus, Source Naturals-Fucoxanthin-90 capsules, Fucogreen, Fucothin, Diet 360, Fucomax, Natural Balance-Slimcare, Natural care-Slimcare, Fucoslim, Fucoxanthin Patch-500 Fucoxanthin Solaray, Absonutrix Fucoxanthin Slim Patch, Vitaplus Fucoslim, Fucoxanthin Plus, Fucoxanthin-Slim, RawTrim Fucoxanthin |
Fig. 2 Mechanism based biosynthesis of carotenoids involving epoxidation and de-epoxidation of xanthophylls along with cellular enzymes. |
Fig. 3 Schematic diagram of carotenoid degradation via oxidation and their break down into lower molecular compounds. |
Carotenoids are relatively stable compounds that accumulate in diverse types of tissues. Recently, it was demonstrated by 14CO2 uptake experiments that carotenoid turnover appears to be much greater than expected.35 In mature leaves, the active degradation of carotenoids by CCD (carotenoid cleavage dioxygenases) and NCED (9-cis-epoxycarotenoid dioxygenase) enzymatic turnover. Members of these gene families are involved in the biosynthesis of the phytohormone ABA (NCED2, 3, 5, 6, 9), which controls abiotic stress signalling pathways and strigolactone (CCD1, 4, 7, 8), which controls shoot growth and root-mycorrhizal symbiosis. The active degradation of the xanthophylls by CCD activity can reduce lutein content in strawberries as well as changes in the pigmentation in chrysanthemums from white to yellow.36 In maturing Arabidopsis seeds a loss of function of CCD1 activity leads to higher carotenoid levels and may have a role in synthesis of apocarotenoid flavour and aroma volatiles.37 Similarly, in tomato (Lycopersicon esculentum) LeCCD1 activity contributes to the formation of the flavour volatiles β-ionone, pseudoionone and geranylacetone.38 The Crocus, zeaxanthin 7,8 (70,80)-cleavage dioxygenase (CsZCD) and 9,10 (90,100)-cleavage dioxygenase (CsCCD) initiate the biogenesis of carotenoid derivatives such as crocetin glycosides, picrocrocin and safranal (saffron).
LPSE offers various disadvantages associated firstly with thermal degradation of bioactive compounds due to high temperature during vaporisation stage; secondly due to utilization of more quantity of organic solvents which are hazardous to environment and human health, so a majority of organic solvents have been restricted for the extraction of bioactive compounds; thirdly it consumes more energy, time and processing labor cost.47 US Environmental Protection Agency has given a list of 189 hazardous air pollutants in which n-hexane occupies number 1 position,49 which reduces its usage levels from 5 mg kg−1 of product to 1 mg kg−1.
S. no. | Extraction methods used | Solvent used | Carotenoids extracted | Fruits & part | References |
---|---|---|---|---|---|
Homogenization | Acetone:ethanol (1:1, v/v), 5% aqueous solution of pyrogallol | β-carotene, cis-β-carotene, α-carotene, antheraxanthin, lutein, zeaxanthin, violaxanthin, neoxanthin, lycopene | Apricot, avocado, blackberry, banana, broccoli, bilberry, carrot, grape, kale, kiwi fruit, lemon, leuttuce, mirabelle, nectarine, papaya, parsley leaf, peach, plum, raspberry, red paprika, strawberry, tomato, spinach | 93 | |
Diethyl ether and acetone | β-Carotene, β-cryptoxanthin, lutein, violaxanthin | Acerola fruits | 94 | ||
Tetrahydrofuran:methanol (1:1, v/v), petroleum ether | Lutein, α-carotene, β-carotene, cis-β-carotene | Beans, broccoli, brussels, cabbage, carrot, cucumber, greens, leeks, lettuce, marrow, pepper, sweet corn, tomato, | 95 | ||
Ethanol:pentane:sodium chloride:water (10:16:2:5 v/v/v/v) | β-Carotene, α-carotene | Broccoli, carrot, collard, corn, squash, turnip | 96 | ||
Immersion | Hexane | Total carotene | Apricot, cntaloupe, grape fruits, peach | 97 | |
Tetrahydrofuran | Neoxanthin, violaxanthin, lutein 5,5-epoxide, trans-lutein, cis-lutein, total lutein, α-carotene, β-carotene | Beans, broccoli | 98 | ||
Agitation | Petroleum ether:methanol (1:1 v/v) | β-Carotene | Apricot | 99 | |
Acetone:ethanol:hexane (1:1:2 v/v/v) | Lycopene, carotenoids, β-carotene, lutein | Guava, red navel, tomato | 100–102 | ||
Hexane:ethyl acetate (85:15 v/v) | β-Carotene | Olive oil | 93 | ||
Dichloromethane:acetone:methanol (2:1:1 v/v/v) | β-Carotene, carotenoids | Paprika | 103 | ||
Tetrahydrofuran | β-Carotene, lutein | Spinach | 104 | ||
Hexane | Lycopene, β-carotene | Tomato | 105 | ||
Water:1-butanol | α-Carotene, β-carotene, lutein, lycopene | Wheat | 106 | ||
Soxhlet | Hexane | β-Carotene, carotenoids, lutein | Buriti, marigold, palm oil, paprika, tomato | 107–111 | |
Diethyl ether | α-Carotene, β-carotene | Cloudberry | 112 | ||
Acetone, hexane | β-Carotene, β-cryptoxanthin, zeaxanthin, capsanthin, trans-lycopene, cis-lycopene | Paprika, tomato | 113 and 114 | ||
Chloroform | Lycopene | Tomato | 115 | ||
Dichloromethane | Lycopene, β-carotene | Tomato | 116 | ||
Ethanol, hexane | Polyoxy xanthophylls, lutein, α-cryptoxanthin, β-cryptoxanthin, lycoxanthin, cis-lycoxanthin, lycopene, neolycopene, Ƴ-carotene, β-carotene | Tomato skins and seed | 117 and 118 | ||
Ultrasound | Ethyl acetate | Bixin, β-carotene | Annatto, carrot | 119 and 120 | |
Chloroform:acetone | β-Carotene, lutein | Stinging nettle | 121 | ||
Chloroform | Lycopene | Tomato skins | 122 and 123 | ||
Shaking | 1,2-Dichloroethane:acetone | β-Carotene | Cardamom | 124 | |
Methanol:tetrahydrofuran (1:1 v/v) | Lutein, zeaxanthin, β-cryptoxanthin | Corn, wheat | 125 | ||
Chloroform:methanol | α-Carotene, β-carotene, lycopene, lutein, zeaxanthin, β-cryptoxanthin | Japanese persimmon | 48a | ||
Centrifugation | Zinc sulphate + monohydrate potassium ferrocyanide | cis-Violaxanthin, β-carotene, lutein | Orange | 109 | |
Ethanol:water:butylated hydroxytoluene (95:5:0.05 v/v/v) | β-Carotene, cryptoxanthin, α-carotene, lutein, lycopene | Pumpkin | 126 | ||
Ethanol:hexane (1:1) | Lutein, α-carotene, β-carotene lutein esters, lycopene | Pumpkin, tomato | 127 and 128 | ||
Tetrahydrofuran:methanol (1:1 v/v) | Lutein, zeaxanthin, β-cryptoxanthin, trans-β-carotene | Spinach, tomato, tangerine | 129 |
Carotene | Source | SFE condition | References | ||
---|---|---|---|---|---|
Temperature (K) | Pressure (bar) | Time (min) | |||
β-Carotene | Apricot | 313–350 | 304–507 | 90–150 | 99, 130 and 131 |
Broccoli | 313 | 342 | 30 | 96 | |
Buriti | 313–328 | 200–300 | 95–210 | 107 | |
Cardamom | 298–328 | 80–300 | 124 | ||
Carrot | 310–330 | 150–250 | 60–300 | 132 | |
Collard greens | 313 | 342 | 30 | 96 | |
Crude palm oil | 333 | 140 | 60 | 133–135 | |
Mustard greens, squash, turnip greens, zucchini | 313 | 342 | 30 | 96 | |
Rosa canina | 343 | 300 | 136 | ||
α-Carotene, β-carotene | Carrot | 303–342 | 404–606 | 96, 137 and 138 | |
Cloudberry | 313–333 | 90–300 | 112 | ||
Corn, vegetables | 313 | 342 | 30 | 96 | |
Carotenoids | Capsicum | 313–333 | 140–300 | 360 | 139 |
Crude palm oil | 313–353 | 140–350 | 140 and 141 | ||
Lotus | 301–344 | 159–441 | 150 | 142 | |
Sea buckthorn | 305–340 | 128–472 | 9–116 | 143 | |
Walnut | 323–343 | 200–400 | 182–470 | 144 | |
Paprika | 333–353 | 300–500 | 145 | ||
Lycopene | Guava | 328 | 300 | 180 | 100 and 146 |
Papaya, pomelo red, rose hip fruits | 363 | 400 | 15 | 141 and 146 | |
Tomato | 313–373 | 200–500 | 330 | 105, 115, 123, 128 and 146–149 | |
Watermelon | 333–363 | 207–414 | 35 | 150 |
Sample | Analyte | Saponification conditions | References |
---|---|---|---|
Juice of red navel orange (Cara cara) | Neoxanthin (a, b), neochrome, violaxanthin, luteoxanthin, antheraxanthin, mutatoxanthin, lutein, isolutein, zeaxanthin, α- and β-cryptoxanthin, phytoene, phytofluene, α-, β- and Ƴ-carotene, lycopene | 10% methanolic KOH sol. (overnight, room T, darkness) | 163 |
Ultrafrozen orange juice | Lutein, zeaxanthin, lutein 5,6-epoxide, antheraxanthin, β-cryptoxanthin | 10% methanolic KOH sol. (1 h, room T, darkness) | 164 |
Fatty foods (fat-cured crude sausage “Sobrassada”) | Capsorubin, violaxanthin, capsanthin, anteraxanthin, lutein + zeaxanthin, cantaxanthin, β-cryptoxanthin, β-carotene | 10% methanolic KOH sol. containing 0.01% BHA (5 min, 50 °C) | 165 |
Marigold (Tagetes erecta) flower extract | All-trans–cis isomers of zeaxanthin, all-trans–cis isomers of lutein, lutein esters | 15% methanolic KOH sol. (1 h, darkness) | 166 |
Standard reference material 2383 (baby food composite) | Lutein, zeaxanthin, β-cryptoxanthin, lycopene, trans–cis α- and β-carotene, retinol, retinyl palmitate, δ-, Ƴ- and α-tocopherol | 40% methanolic KOH sol. (30 min, room T) | 167 |
Raw and cooked spanish vegetables (lettuce, artichokes, brussel sprouts, green beans, asparagus (green), beet, green peppers, spinach, tomato, red peppers, carrots, red cabbage, cucumber, squash, potato, onion, cabbage, cauliflower) | Lutein, zeaxanthin, lycopene, b-cryptoxanthin, α-, β- and Ƴ-carotene | Saturated methanolic KOH sol. (under nitrogen atmosphere, 30 min, darkness) | 168 |
Edible wild vegetable stinging nettle (Urtica dioica L.) | Lutein, lutein isomers, β-carotene, β-carotene isomers, neoxanthin, violaxanthin, lycopene | Methanolic KOH sol. (room T) | 169 |
Virgin olive oil | α-Tocopherol and β-carotene | 76% ethanolic KOH sol. (under nitrogen atmosphere, 30 min, 70 °C) | 170 |
Corn | Lutein, zeaxanthin, and β-cryptoxanthin | 80% ethanolic KOH sol. (in a water bath at boiling point, 10 min) | 171 |
Fresh and processed vegetables (broccoli, carrots and green beans) | trans-β-Carotene | 100% ethanolic KOH sol. (30 min, 70 °C) | 172 |
Sweet potato (Ipomoea batatas, L.) | α-Carotene, β-carotene | 10% ethanol:water (50:50, v/v) for 1 h, 80 °C | 173 |
Milk samples | β-Carotene | 60% aqueous KOH sol. containing pyrogallol as antioxidant (30 min, 30 °C) | 174 |
Fortified foods (fortified breakfast cereal, peanut butter and margarine) | All-rac-alpha-tocopheryl acetate, retinyl palmitate, β-carotene | 60% aqueous KOH sol. containing pyrogallol as antioxidant (under nitrogen atmosphere, 30 min, 70 °C) | 175 |
Kale (Brassica oleracea var. acephala cv. Vates) | Lutein, β-carotene, retinol, phylloquinone | 80% aqueous KOH sol. (15 min, 70 °C) | 176 |
S. no. | Analyte & wave-length | Mobile phase | Column/detection | References |
---|---|---|---|---|
β-Carotene & 451 nm | Methanol 65%, THF 27% and water 6% | C18 column | 59 | |
65% methanol, 27% acetonitrile, 4% methylenediclorure and 4% hexane | C18 RS 5 μm column | 131 | ||
Methanol with 10% (v/v) acetonitrile | C18 column | 187 | ||
Acetonitrile (ACN), dichloromethane (DCM) and methanol (MeOH) 5:4:1 v/v/v, containing 0.1% BHT | Luna C18 coupled to a Jupiter C18 column | 188 | ||
Methanol, water and t-BME | ODS-C18, Tracer Extrasil (5 μm)/PDA | 189 | ||
Acetonitrile, water and ethyl acetate | 190 | |||
Acetonitrile, propranolol, methanol and water | 5C18-MS Waters column | 191 | ||
Acetonitrile, methanol, dichloromethane | ODS2 column; STR-ODS-II column | 192 and 193 | ||
Methanol/methyl tert-butyl ether (MTBE)/water (81:15:4, v/v/v; A), and methanol/MTBE/water (4:92:4, v/v/v; B) | C30 column | 127 and 194 | ||
Neoxanthin, β-cryptoxanthin, lutein, α-, β-carotene, violaxanthin, violeoxanthin, lutein and several cis isomers | Methanol, propranolol and dichloro methane | Silica C30 (5 μm)/PDA | 195 and 196 | |
Methanol, t-BME | C18 Nucleosil (5 μm)/LC-MS | 197 | ||
Lycopene, β-cryptoxanthin, α-, β-carotene, lutein, zeaxanthin isomers | Acetonitrile, dichloromethane and t-BME; acetonitrile:dichloromethane (65:35 v/v) | C18 Spherisorb (5 μm)/PDA; C18 octadecyl silane | 53 and 198 | |
α-, β-Carotene, lutein, lycopene, β-cryptoxanthin, phytoene, phytoene | Acetonitrile, methanol and propanol | C18 Spherical (5 μm)/PDA | 199 | |
Lycopene, β-carotene | Methanol, THF and water | C18 Symmetry (5 μm)/PDA | 83b | |
Lutein, α-, β-carotene, β-cryptoxanthin, zeaxanthin | Acetonitrile, dichloromethane, methanol | Silica C18 Nucleosil C18 Techsphere ODS Spherisorb ODS Spherisorb C8 (3 μm, 5 μm)/UV-MS | 200 | |
Valenciaxanthin, neochrome, α-, β-cryptoxanthin, lutein, antheraxanthin, trolichrom, neoxanthin, auroxanthin, leutoxanthin, phytofluene | t-BME, methanol and water | Silica C30 Spheres (3 μm)/PDA | 201 | |
Astaxanthin, zeaxanthin, canthaxanthin, echineone, lycopene, β-carotene | Methanol, t-BME | Silica C30 (3 μm)/UV-MS | 202 |
Sample | Analyte | Extraction protocol | Detection system | References |
---|---|---|---|---|
Plasma | Lutein, zeaxanthin, β-cryptoxanthin, α-carotene, β-carotene, lycopene, phytoene, phytofluene, 36 different carotenoid isomers | Centrifuged blood treated with ethanol (0.1% BHT) and heated with hexane, ethanol, acetone and toluene; sometimes saline treated blood extracted with ethyl acetate | LC-PDA, C30 column, mobile phase: methanol:MTBE:H2O:2% aqueous ammonium acetate solution, 88:5:5:2, v/v/v/v | 229 |
LC-PDA, Si60 (250 mm × 4 mm, 5 lm) column mobile phase: n-hexane and acetone (19% by vol) | 232 | |||
LC-PDA C18 column mobile phase: (A) 0.0125% ammonium acetate in MeOH, (B) 100% CHCl3 and (C) CH3CN with 0.1% triethylamine gradient elution | 227 | |||
UPLC-PDA-APCI(−)/MS, C30 (150 mm × 4.96 mm, 5 lm) column mobile phase: (A) MeOH/0.1% aqueous formic acid solution (80:20) (B) MTBE/MeOH/0.1% aq. formic acid solution (78:20:2) | 230 | |||
Serum | Lutein, zeaxanthin, β-cryptoxanthin, α-carotene, β-carotene, lycopene, phytoene, phytofluene | 200 μL plasma extracted twice with 1 mL of hexane containing 0.01% BHT. Dried under N2; reconstituted in mobile phase | LC-PDA-APCI (+)/MS C30 column mobile phase: (A) MeOH/ACN/water (84:14:4, v/v/v) and (B) DCM gradient elution | 212 |
SFC/MS/MS, ODS (250 mm × 4.6 mm, 5 lm) column mobile phase: carbon dioxide (99.99% grade). Modifier: MeOH with 0.1% (w/v) ammonium formate | 238 | |||
LC-UV-Vis, C30 (4.6 mm × 25 mm, 5 lm) column, guard C30 column mobile phase: (A) MeOH:ACN (40:60, v/v) (B) MeOH:ACN (25:75, v/v) and (C) MTBE gradient elution | 235 | |||
LC-PDA, ODS 2 C18 (3 mm × 250 mm, 3 lm) column connected with a ODS 2 guard column mobile phase: ACN:methylene chloride:methyl alcohol (7:2:1, v/v/v) isocratic elution | 233 | |||
LC-PAD RP C18 mobile phase: MeOH/THF/H2O (94:5:1) | 241 | |||
Reversed phase HPLC, C30 (250 mm × 4.6 mm, 5 lm) column in line with a C18 pre-column mobile phase: (A) MeOH/water (90:10, v/v, with 0.4 g L−1 ammonium acetate in H2O) (B) MeOH/MTBE/water (8:90:2 v/v/v, with 0.1 g L−1 ammonium acetate in H2O) | 226 | |||
LC-APCI (+)/MS, RP C30 (150 mm × 4.6 mm, 3 lm) mobile phase: (A) MeOH/tert-butyl methyl ether/water (83:15:2, v/v/v) and (B) MeOH/MTBE/water (8:90:2, v/v/v) gradient elution | 242 | |||
HPLC-APCI(+)/MS, C30 (4.6 × 250 mm, 5 lm) carotenoid column mobile phase: (A) MeOH/MTBE/water (8:90:2) containing 2.6 mmol L−1 of ammonium acetate | 243 | |||
Red blood cells | Lutein, zeaxanthin, β-cryptoxanthin, α-carotene, β-carotene, lycopene, phytoene, phytofluene | 2.5 mL + 2.5 water + 5 mL pyrogallol (0–400 mmol L−1 in ethanol) + 1 mL aqueous potassium hydroxide (0–7 mmol L−1) and 40 lL of echinone (1 lmol L−1 in ethanol); sonicated for 5 min; vortexed for 2 min, incubated at various temp. (20–70) for different time periods (0–24 h). Mixed; extracted with 1.25 mL of 0.1 mol L−1 sodium dodecyl sulfate aqueous solution and 15 mL of hexane/dichloromethane (5:1, v/v) containing 1.2 mmol L−1 BHT; sonicated, vortexed, centrifuged at 1000g for 10 min. Supernatants collected extraction repeated. Supernatants evaporated under N2; reconstituted in 3 mL of hexane/acetone (2:1, v/v) and eluted with 7 mL of hexane/acetone (2:1, v/v); eluent evaporated and residue dissolved in 100 lL of MeOH/MTBE (2:3, v/v), 100 | LC-PDA-APCI(+)/MS, C30 (250 mm × 4.6 mm I.D, 5 lm) column mobile phase: (A) MeOH/MTBE/water (83:15:2, v/v/v) containing 3.9 mmol L−1 ammonium acetate (B) MeOH/MTBE/water (8:90:2, v/v/v) containing 2.6 mmol L−1 ammonium acetate | 231 |
Fig. 6 Effect of β-carotene on oxidative stress indicating β-carotene as antioxidant in non-smokers and as pro-oxidant in smokers. |
Fig. 7 Schematic diagram showing anti-carcinogenic effect of fucoxanthin via apoptosis, cell cycle arrest and metastasis suppression. |
Among all extraction methods employed for carotenoids till now, supercritical carbon-dioxide extraction have been found to be the best for extraction of carotenoids under optimized conditions leading to best yield, high purity and an environmental friendly technique as well. Saponification process needs to be employed prior to analysis of the extracts to remove undesired components such as lipids which interfere during the analysis of carotenoids. UPLC-MS have been found to be of great importance in the analysis of a variety of carotenoids. There is a lot of scope for the extraction and analysis of novel carotenoids from unexplored natural sources and their valuable roles in the humans and animals which is of high need in developing countries where major portion of population are lacking proper diet.
This journal is © The Royal Society of Chemistry 2015 |