Carotenoids are plant pigments that are widely found in fruits and vegetables. They are red, yellow and orange in colour, mainly produced by plants, algae and photosynthetic bacteria. Lycopene and beta carotene are only two of the 600 types of carotenoids known. Lutein, zeaxanthin, beta carotene, alpha carotene, beta cryptoxanthin, and lycopene are some important nutrients that are commonly seen in the human diet.
Carotenoids are divided into categories: Xanthophylls and Carotenes.
- Xanthophylls are more of a yellow pigment and contain oxygen in their structure. E.g., Lutein and Zeaxanthin.
- Carotenes are more of an orange pigment and are devoid of oxygen in their structures. E.g., Lycopene and Beta Carotene.
What is Lycopene?
Lycopenes are bright red coloured carotenes commonly found in tomatoes, carrots, watermelon, grapefruits and papayas. However, it is not found in strawberries and cherries.
Chemically, it is a tetrapene composed of eight isoprene units. The thirteen conjugated double bonds give the structure its red colour. The molecular formula of lycopene is C40H56.
Although it is a carotene, it possesses no provitamin A activity. Therefore, it is not an essential nutrient in the human diet but is consumed commonly. However, lycopene is an important carotenoid since it functions as a precursor for the formation of beta carotene and xanthophylls. It is present in small amounts in all of the plants.
What is Beta Carotene?
Beta carotenes are reddish-orange carotenes commonly found in mangoes, pumpkin, oranges, papayas, carrots and sweet potatoes.
It is composed of eight isoprene units with a molecular formula of C40H56. It can be distinguished from other carotenoids in having the presence of beta rings at both the ends of the molecule.
Beta carotene serves as a precursor in the formation of Vitamin A.
Beta carotene itself is not an essential requirement in the diet. However, it is available as a supplement in many multivitamin formulations.
Beta carotenes are found widely in green leaves. Their functions include: (1) collection of light and transferring it to chlorophyll, (2) dissipation of the excess energy. They also help in the formation of tertiary structures of the chloroplast.
Lycopene vs Beta Carotene
|Lycopene is a bright red coloured hydrocarbon.||Beta carotene is a red-orange coloured hydrocarbon.|
|Vitamin A Activity|
|Lycopene is the chief precursor for Vitamin A that is a chief component in the human diet.||Beta carotene has no provitamin A activity.|
|Number of Double Bonds|
|The presence of two additional unconjugated double bonds gives lycopene a greater singlet oxygen quenching capacity.||Beta carotene also possesses a good antioxidant activity but falls short in front of lycopene.|
|It can be absorbed throughout the intestine.||Its absorption is limited to the duodenum.|
|It does not have beta rings.||It can be distinguished by the presence of beta rings at both ends of their molecule.|
|None||Some studies have shown that beta carotene promotes carcinogen metabolism.|
|It is mostly present in -cis form.||It is mostly present in -trans form.|
|Half Life in Circulation|
|It has a half life of 12-33 days.||The maximum half life is 12 days.|
|It is moderately available in fruits and vegetables, maximum in tomatoes.||It is poorly distributed in fruits and vegetables.|
Visit BYJU’S Biology to learn more.
- Biological Pigments in Plants – Types and Uses
- Separation Of Plant Pigments Through Paper Chromatography
- Why Can’t You See All the Pigments in a Leaf?
- What Is The Main Photosynthetic Pigment?
Frequently Asked Questions on Difference between Lycopene and Beta Carotene
Which is more polar lycopene or beta carotene?
Beta carotene is less polar because it has fewer double bonds.
What’s lycopene good for?
Lycopene, abundantly found in tomatoes, is an excellent antioxidant that scavenges free radicals from our bodies.
What are the similarities between lycopene and beta carotene?
The similarities between lycopene and beta carotene are:
- Both have the molecular weight of 536.6g/mol.
- Both are made of 8 isoprene units.
- Both possess antioxidant properties.
- Both are lipophilic in nature.
- Both have the molecular formula C40H56.
What is the difference between alpha-carotene and beta-carotene?
The major difference between alpha and beta carotene is the position of the double hydrogen bond. Moreover, beta-carotene is more commonly found than alpha carotene.
What are the side effects of beta-carotene?
Consumption of too much beta carotene-rich foods can lead to a condition called carotenodermia. It is recognized by discolouration of hands and feet in yellow and orange colour.
Are carotenoids toxins?
Generally, carotenoids are non-toxic. Conditions caused by high consumption of carotenoids can be balanced by taking meals low in that particular carotenoid.