What is carotenoid and its origin course

What are 1. carotenoids?
Auxiliary pigment (accessory pigment): In plants and photosynthetic bacteria, such as the carotenoids lutein and phycobilin, a pigment that absorbs visible light and supplements the capture of light by chlorophyll.

Unsaponifiable lipids. It is a group of yellow, orange, red or purple pigments widely distributed in animals and plants. The conjugated double bond constituting the cause of color development has a long-chain polyolefin structure. Usually several are mixed together. There are more terpene structures with C40 and no nitrogen. It is known that there are about 300 kinds of natural carotenoids, among which the hydrocarbon classes without oxygen include carotene, mycopelin, etc. There are many oxygen-containing ones, such as alcohols, ketones, ethers, aldehydes, epoxides, carboxylic acids and esters, etc. Among them, there are a large number of fucoxanthin (fucoxanthin), lutein (lutein), cordioxanthin (violaxanthin), new xanthin (neoxanthin), etc., all belong to carrot alcohol. Most carotenoids are insoluble in water, soluble in lipid solvents, unstable and easily oxidized.

Characteristics and distribution of carotenoids in 2.
Main features

Carotenoids (carotenoid): A general term for an important class of natural pigments that are compounds. A yellow, orange-red, or red pigment, mainly beta-carotene and gamma-carotene, commonly found in animals, higher plants, fungi, algae, and bacteria, hence the name. Insoluble in water, soluble in fats and fatty solvents. Also known as fat pigment. Since the early 19th century isolated carotenoids, has been found nearly 450 kinds of natural carotenoids; the use of new separation and analysis techniques such as thin layer chromatography, high pressure liquid chromatography and mass spectrometry analysis also continue to find new carotenoids. Carotenoids of plants are found in various yellow or chromoplasts; such as yellow leaves in autumn, yellow flowers, yellow and red fruits and yellow roots. The carotenoids of animals are mainly the pigments of fat, egg yolk, feathers and fish scales, and the carapace of shrimp and crabs. Animal carotenoids are generally combined with proteins. For example, shrimp green protein contains astaxanthin, and shrimp green protein is a complex of astaxanthin and a rich mixture. Beta-carotene is a precursor of vitamin A synthesis in mammals, called provitamin A. Chloroplasts in addition to containing chlorophyll also contains carotenoids, carotenoids can absorb the light energy transferred to chlorophyll a, photosynthesis is indispensable photosynthetic pigment. Lutein, an important antioxidant, is a member of the carotenoid family (a group of naturally occurring, fat-soluble pigments found in plants) and is found in nature together with zeaxanthin.

correlation distribution

In nature, carotenoids are widely distributed and synthesized in photosynthetic and non-photosynthetic tissues of higher plants (including leaves, flowers, fruits and roots) and microorganisms (including algae and some photosynthetic and non-photosynthetic bacteria). Many animals (especially aquatic animals) are also rich in carotenoids. For example, there are often a lot of carotenoids in the hair, skin and egg yolk of birds. But so far, there is no evidence that animals themselves can biosynthesize carotenoids. Carotenoids in all animals are ultimately derived from plants and microorganisms through the food chain.

Strictly speaking, natural carotenoids can be considered as products of biosynthesis in living cells or as products of metabolic processes in animals.

A large number of studies on carotenoid biosynthesis in organisms, including photosynthetic and non-photosynthetic tissues of higher plants (such as Zea mays, Lycopersicon esculentum, Narcissus pseudonarcissus and Capsicum annuum), fungi (such as Neurospora and Phycomyces), algae (such as Dunaliella) and bacteria (such as Rhodobacter species), have been reported, reviewed and reviewed in many publications and publications.

What is the use of 3. carotenoids
Carotenoids are highly unsaturated compounds (polyenes) containing a series of conjugated double bonds and methyl branches. The color of the pigment varies with the number of conjugated double bonds. The greater the number of conjugated double bonds, the further the color shifts to red.

Some carotenoids are used in industry as food and fat.

Coloring agents, such as beta-carotene, lycopene, zeaxanthin, lutein, capsicum red, crocin, saffron acid, annatto, red yeast red pigment, etc.

Vitamin A is a colorless, fat-soluble isoprenoid alcohol. In animals, beta-carotene plus two molecules of water breaks down into two molecules of retinol (I. e., vitamins A and A are found in the liver, blood, and retina of the eyeball; A is found only in freshwater fish). In the dark, all-trans retinal is converted into 11 cis retinal in order to combine with opsin to form rhodopsin, which is related to dark vision, so vitamin A deficiency leads to night blindness.

Carotenoids contain many double bonds and are good singlet oxygen quenchers. its mechanism of action

It is the singlet oxygen in the excited state that transfers energy to the carotenoid, causing the carotenoid to change from the ground state (carotenoid) to the excited state (carotenoid), which can return directly to the ground state.

O2 carotenoid → O2 carotenoid

Carotenoids → Carotenoids

In addition, the singlet oxygen quencher may also return the photosensitizer to the ground state.

Carotenoids Sen → Carotenoids Sen.

What is the effect of 4. carotenoids

1. Health care for the visual system

Rod cells on the retina contain rhodopsin and have the function of scotopic vision. Proper amount of β-carob can promote the normal content of rhodopsin, thus avoiding the lack of vitamin A caused by the dark field to adapt to slow, but also to avoid the dark field after the emergence of light damage to the eyes. In addition, it can also prevent night blindness, dry eye, corneal ulcer and keratomalacia;

2. Health care for skin tissue

VA is necessary to maintain the integrity of all epithelial tissues, and beta-carob can be converted into VA in the human body. Therefore, the intake of a certain amount of β-carotene is of great significance to maintain normal body surface, digestive tract, respiratory tract, genitourinary tract and endocrine tract commodities, and can avoid skin diseases such as skin dandruff, keratinization, hard scaly epidermal cells, multi-horny blood rash skin dryness. β-carotene also has a good effect on the stability of cell membranes. It can also be used to treat inflammation caused by sun exposure, "sun inflammation".

3. Resistance to adverse environments

Those who often work in dark rooms, bright light, high temperature or deep water, as well as radiation workers, as well as those who often watch TV, should supplement beta-carotene to resist the adverse environment.