Carotene

α-carotene

β-carotene

Two carotene isomers are distinguished: α-carotene and β-carotene. β-carotene is found in the yellow, orange, and green leaves of fruits and vegetables. For example, in spinach , lettuce, tomatoes , sweet potato and others.

Nomenclature

The two terminal fragments ( β-rings ) of the β-carotene molecule are structurally identical. The α-carotene molecule contains two terminal cyclic fragments, characterized by the location of the double bond in the ring. One of the terminal fragments is called the β-ring , identical to the β-ring of β-carotene, the other is called the ε-ring .

The following options for the spatial arrangement of parts of the molecule that determine the structure of the isomer are possible :

• α-Carotene β, ε-Carotene ;
• β-Carotene β, β-Carotene ;
• γ-Carotene (with one β ring and one non-cyclized end, which is indicated by the letter psi ) - β, ψ-Carotene ;
• δ-Carotene (with one ε-ring and one non-cyclized end) - ε, ψ-Carotene ;
• ε-Carotene ε, ε-Carotene

Despite the fact that carotene can be obtained using chemical synthesis, it is produced mainly from natural raw materials.

Plants (for example, pumpkin , carrots ), bacteria (some strains of staphylococci ), algae and fungi with a high content of the target substance are used as sources of carotene.

Carotenoids are obtained by chemical synthesis ^{[1] [2]} and by isolation from natural sources - plants and microorganisms ^{[3] [4] [5]} . The use of plants as a source of carotenoids also has several disadvantages: it is seasonal in nature; depends on the ecological state of soils and plant yields, significantly reduced due to the accumulation of sources of diseases of plant materials; there is a need for large sown areas for growing plants. In addition, the bioavailability of the source of carotenoids from vegetable juice is low due to the presence of carotenoids in protein complexes, which greatly complicates their release. The digestibility of carotene from vegetables with a diet without fats is very low.

Microbiological synthesis of beta-carotene is the most justified industrial method of its production from both technological and economic points of view ^[6] . “Microbiological” carotenoids, including beta-carotene, are obtained from the cells of mycelial fungi, yeast, bacteria, actinomycetes and algae ^{[7] [8] [9]} . Mushrooms are of great importance as producers of various biologically active substances for the food industry, medicine, agriculture and other industries. The microscopic mucinous mushroom Blakeslea trispora is no exception. The strains of Blakeslea trispora are superproducers of β-carotene and lycopene ^{[10] [11] [12] [13]} and, in addition, the biosynthesis of other valuable compounds of a terpenoid nature is possible - ubiquinones, ergosterol ^{[14] [15] [16]} . During carotene biosynthesis by microorganisms, it accumulates in producer cells. Blakeslea trispora's own fats comprise up to 60% of the total biomass, which contributes to the dissolution of carotene during fermentation. This accordingly increases its availability for assimilation. The technology for producing microbiological carotenoids is environmentally friendly due to the absence of harmful emissions and the use of non-aggressive chemicals. The raw materials in the production of carotenoids are by-products, intermediate products and wastes of starch and syrup production, flour milling, canning, oil and meat and dairy industries.

Description

Beta-carotene is a yellow-orange plant pigment , one of 600 natural carotenoids . Beta-carotene is a precursor to vitamin A ( retinol ) and is a powerful antioxidant . Also, this substance has an immunostimulating and adaptogenic effect ^[17] .

Sources

Pumpkin, carrot, green onion, sorrel, spinach, lettuce, lettuce, romano salad, cabbage cale , tomatoes, red pepper, broccoli, grapefruit, plums, peaches, melons, apricots, persimmons, gooseberries, blueberries, black currants.

Beta-carotene is found in a unique salt deposit in the Crimea on Lake Sasyk . The natural component gets into salt pools thanks to the flowering of the algae Dunaliella sallina, which was able to adapt to the harsh conditions of ultra-salted water and solar radiation, having learned how to produce beta-carotene. Thus, beta-carotene accompanies the main components of natural sea salt.

Daily requirement

According to the guidelines for rational nutrition, “Norms of physiological requirements for energy and nutrients for various groups of the population of the Russian Federation” dated December 18, 2008 (MP 2.3.1.2432 −08) ^[18] , 6 mg of beta-carotene are equivalent to 1 mg of vitamin A. The average consumption in different countries is 1.8-5.0 mg / day. There is no upper allowable consumption level. The physiological need for adults is 5 mg / day (administered for the first time).

Long-term use of beta-carotene is not accompanied by any side effects.

Subsequent studies have shown that, in reality, the vitamin activity of carotenoids is two times lower than what was previously thought. Therefore, in 2001, the US Institute of Medicine proposed another new unit - the equivalent of retinol activity (RAE). 1 RAE corresponds to 1 μg of retinol, 2 μg of β-carotene dissolved in fat (in the form of a pharmaceutical preparation), 12 μg of “food” β-carotene, or 24 μg of other provitamins A.

Mechanism of Action

The unsaturated structure of beta-carotene allows its molecules to absorb light and prevent the accumulation of free radicals and reactive oxygen species. Beta-carotene inhibits the production of free radicals. It is believed that thereby it protects the cells of the immune system from damage by free radicals and can improve the state of immunity ^[17] . Beta-carotene is a natural immunostimulant that increases the body's immune potential regardless of the type of antigens , that is, it acts non-specifically.

Some studies have shown its weakly expressed immunostimulating effect ^[19] .

There are many publications regarding the effect of beta-carotene on the increase in the number of T-helpers . Moreover, in some experiments, an increase in the number of all T-lymphocytes, and in some only T-helpers, is recorded ^[20] .

The greatest effect is shown in individuals (people and animals) experiencing peroxide stress (improper diet, diseases, old age). In completely healthy organisms, the effect is often minimal or absent ^[21] .

The effect itself is associated with an increase in the proliferative ability of T-lymphocytes , including T (0,1,2) -helpers. The proliferation of T-lymphocytes is inhibited by the peroxide radical. The elimination of peroxide radicals increases the ability of T cells to blastogenesis. Beta-carotene also stimulates the growth of thymus glands, the sources of T-lymphocytes, in animals ^[22] .

This is a non-specific effect of most lipophilic antioxidants (lutein, cryptoxanthin, retinol, tocopherol, alpha-carotene, astaxanthin) ^[23] .

The episodic accumulation of T-helpers, and not other lymphocytes, is apparently associated with a specific cytokine situation in the body ^[24] .

An increase in the proliferative ability of T-lymphocytes under the influence of beta-carotene is also shown in model experiments with cultures of lymphocytes (and not only T-lymphocytes). The use of specific mitogens (CON A) leads to proliferation of lymphocytes. This is an imitation of the cytokine environment in the immune response. Beta-carotene T-lymphocytes proliferate more than control ones. Studies have concluded that with infection, beta-carotene will accelerate the immune response ^[25] . The growth and differentiation of T-helpers also depends on the presence of interleukins 1,2,4. These cytokines are formed in the T-lymphocytes and macrophages themselves. Beta-carotene significantly increases the activity of macrophages , since they undergo specific peroxidation processes that require a large amount of antioxidants. In addition to phagocytosis, macrophages present antigen and stimulate the corresponding T-helpers. This leads to an increase in the number of T-helpers. But only in the presence of antigen ^[26] .

Some domestic scientists attribute the immunomodulatory activity of beta-carotene to the effect on arachidonic acid and its metabolites ^[27] .

In particular, it is believed that beta-carotene inhibits the production of arachidonic acid products (refers to omega fatty acids), thereby inhibiting the production of prostaglandin E2 (a lipid physiologically active substance) ^[28] . Prostaglandin E 2 is a suppressor of NK cells, reducing its content, beta-carotene enhances the activity of NK cells producing gamma- interferon . Thus, beta-carotene carries out its immunostimulating effect ^[29] .

Beta Carotene Preparations

• Vetoron (allowed from 3 years)
• Betaviton (allowed from 14 years old)
• Triovit (allowed from 12 years old)

Carotinemia or hypercarotinemia is an excess of carotene in the body (unlike excess vitamin A, carotene is low toxic). Usually carotinemia is not considered a dangerous condition, although it leads to yellowing of the skin ( carotenoderma ). It is often observed if there is a lot of carrots in food, but can also be a symptom of more dangerous conditions.

Previous studies have shown that beta-carotene, being an antioxidant, reduces the likelihood of getting cancer with people who consume a lot of beta-carotene-rich foods. But recent major studies have shown that the use of beta-carotene leads to an increase in the likelihood of lung cancer and prostate cancer in smokers, as well as people working in asbestos production ^[30] .

The first study, published in 1994 in The New England Journal of Medicine ^[31], showed that taking beta-carotene increased the likelihood of cancer in smokers by 18%.

A second study, published in the Journal of the National Cancer Institute ^[32] , showed a 28% increase in cancer among smokers.

Recently summarized recent scientific evidence supports the hypothesis that in smokers, consuming high doses of beta-carotene may increase the risk of lung cancer ^[33] .

However, this action of carotene applies only to smokers and people in contact with harmful substances. The specific mechanism of this effect of carotene is unknown.

Many plants, in the aroma of which ionon plays a significant role, owe their smell to a significant concentration of carotene, the structural precursor of the ionon molecule.

• Nutritional supplements

• Detailed beta carotene video tutorial
• Berkeley Wellness Guide to Dietary Supplements
• Beta-carotene on university of maryland
• Beta-carotene Crimean salt lakes
• VESTI 24 - A rare algae was discovered in the Sol-Iletsk lake