Oxygenated forms of carotenoids. They are usually derived from alpha and beta carotene.
A xanthophyll found in the major LIGHT-HARVESTING PROTEIN COMPLEXES of plants. Dietary lutein accumulates in the MACULA LUTEA.
The general name for a group of fat-soluble pigments found in green, yellow, and leafy vegetables, and yellow fruits. They are aliphatic hydrocarbons consisting of a polyisoprene backbone.
A carotenoid that is a precursor of VITAMIN A. It is administered to reduce the severity of photosensitivity reactions in patients with erythropoietic protoporphyria (PORPHYRIA, ERYTHROPOIETIC). (From Reynolds JEF(Ed): Martindale: The Extra Pharmacopoeia (electronic version). Micromedex, Inc, Engewood, CO, 1995.)
A large family of proteins that have been traditionally classified as the light-harvesting proteins of the photosynthetic reaction complex. Chlorophyll binding proteins are also found in non-photosynthetic settings where they may play a photoprotective role in response to light stress.
A large multisubunit protein complex found in the THYLAKOID MEMBRANE. It uses light energy derived from LIGHT-HARVESTING PROTEIN COMPLEXES to catalyze the splitting of WATER into DIOXYGEN and of reducing equivalents of HYDROGEN.
A trans-carotenoid pigment widely distributed in nature. The compound is used as an oral suntanning agent and as a food and drug coloring agent. Oral ingestion of the compound causes canthaxanthin retinopathy.
The passive movement of molecules exceeding the rate expected by simple diffusion. No energy is expended in the process. It is achieved by the introduction of passively diffusing molecules to an enviroment or path that is more favorable to the movement of those molecules. Examples of facilitated diffusion are passive transport of hydrophilic substances across a lipid membrane through hydrophilic pores that traverse the membrane, and the sliding of a DNA BINDING PROTEIN along a strand of DNA.
Complexes containing CHLOROPHYLL and other photosensitive molecules. They serve to capture energy in the form of PHOTONS and are generally found as components of the PHOTOSYSTEM I PROTEIN COMPLEX or the PHOTOSYSTEM II PROTEIN COMPLEX.
Porphyrin derivatives containing magnesium that act to convert light energy in photosynthetic organisms.
Centers for storing various parts of the eye for future use.
Any normal or abnormal coloring matter in PLANTS; ANIMALS or micro-organisms.
Protein complexes that take part in the process of PHOTOSYNTHESIS. They are located within the THYLAKOID MEMBRANES of plant CHLOROPLASTS and a variety of structures in more primitive organisms. There are two major complexes involved in the photosynthetic process called PHOTOSYSTEM I and PHOTOSYSTEM II.
Membranous cisternae of the CHLOROPLAST containing photosynthetic pigments, reaction centers, and the electron-transport chain. Each thylakoid consists of a flattened sac of membrane enclosing a narrow intra-thylakoid space (Lackie and Dow, Dictionary of Cell Biology, 2nd ed). Individual thylakoids are interconnected and tend to stack to form aggregates called grana. They are found in cyanobacteria and all plants.
An oval area in the retina, 3 to 5 mm in diameter, usually located temporal to the posterior pole of the eye and slightly below the level of the optic disk. It is characterized by the presence of a yellow pigment diffusely permeating the inner layers, contains the fovea centralis in its center, and provides the best phototropic visual acuity. It is devoid of retinal blood vessels, except in its periphery, and receives nourishment from the choriocapillaris of the choroid. (From Cline et al., Dictionary of Visual Science, 4th ed)
Enzymes of the isomerase class that catalyze reactions in which a group can be regarded as eliminated from one part of a molecule, leaving a double bond, while remaining covalently attached to the molecule. (From Enzyme Nomenclature, 1992) EC 5.5.
Expendable and nonexpendable equipment, supplies, apparatus, and instruments that are used in diagnostic, surgical, therapeutic, scientific, and experimental procedures.
That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.
Basic lipopeptide antibiotic group obtained from Bacillus polymyxa. They affect the cell membrane by detergent action and may cause neuromuscular and kidney damage. At least eleven different members of the polymyxin group have been identified, each designated by a letter.
Expanded structures, usually green, of vascular plants, characteristically consisting of a bladelike expansion attached to a stem, and functioning as the principal organ of photosynthesis and transpiration. (American Heritage Dictionary, 2d ed)
The synthesis by organisms of organic chemical compounds, especially carbohydrates, from carbon dioxide using energy obtained from light rather than from the oxidation of chemical compounds. Photosynthesis comprises two separate processes: the light reactions and the dark reactions. In higher plants; GREEN ALGAE; and CYANOBACTERIA; NADPH and ATP formed by the light reactions drive the dark reactions which result in the fixation of carbon dioxide. (from Oxford Dictionary of Biochemistry and Molecular Biology, 2001)
Widely distributed enzymes that carry out oxidation-reduction reactions in which one atom of the oxygen molecule is incorporated into the organic substrate; the other oxygen atom is reduced and combined with hydrogen ions to form water. They are also known as monooxygenases or hydroxylases. These reactions require two substrates as reductants for each of the two oxygen atoms. There are different classes of monooxygenases depending on the type of hydrogen-providing cosubstrate (COENZYMES) required in the mixed-function oxidation.
A large multisubunit protein complex that is found in the THYLAKOID MEMBRANE. It uses light energy derived from LIGHT-HARVESTING PROTEIN COMPLEXES to drive electron transfer reactions that result in either the reduction of NADP to NADPH or the transport of PROTONS across the membrane.
The study of the origin, nature, properties, and actions of drugs and their effects on living organisms.
Antibiotic complex produced by Streptomyces fradiae. It is composed of neomycins A, B, and C. It acts by inhibiting translation during protein synthesis.
A plant genus of the family BRASSICACEAE that contains ARABIDOPSIS PROTEINS and MADS DOMAIN PROTEINS. The species A. thaliana is used for experiments in classical plant genetics as well as molecular genetic studies in plant physiology, biochemistry, and development.
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
Naturally occurring or synthetic substances that inhibit or retard the oxidation of a substance to which it is added. They counteract the harmful and damaging effects of oxidation in animal tissues.
Proteins that originate from plants species belonging to the genus ARABIDOPSIS. The most intensely studied species of Arabidopsis, Arabidopsis thaliana, is commonly used in laboratory experiments.
Proteins found in plants (flowers, herbs, shrubs, trees, etc.). The concept does not include proteins found in vegetables for which VEGETABLE PROTEINS is available.

A survey of serum and dietary carotenoids in captive wild animals. (1/814)

Accumulation of carotenoids varies greatly among animal species and is not fully characterized. Circulating carotenoid concentration data in captive wild animals are limited and may be useful for their management. Serum carotenoid concentrations and dietary intakes were surveyed and the extent of accumulation categorized for 76 species of captive wild animals at Brookfield Zoo. Blood samples were obtained opportunistically from 275 individual animals immobilized for a variety of reasons; serum was analyzed for alpha- and beta-carotene, lutein + zeaxanthin, lycopene, beta-cryptoxanthin and canthaxanthin. Total carotenoid content of diets was calculated from tables and chemical analyses of commonly consumed dietary components. Diets were categorized as low, moderate or high in carotenoid content as were total serum carotenoid concentrations. Animals were classified as unknown, high, moderate or low (non-) accumulators of dietary cartenoids. Nonaccumulators had total serum carotenoid concentrations of 0-101 nmol/L, whereas accumulators had concentrations that ranged widely, from 225 to 35,351 nmol/L. Primates were uniquely distinguished by the widest range of type and concentration of carotenoids in their sera. Most were classified as high to moderate accumulators. Felids had high accumulation of beta-carotene regardless of dietary intake, whereas a wide range of exotic birds accumulated only the xanthophylls, lutein + zeaxanthin, canthaxanthin or cryptoxanthin. The exotic ungulates, with the exception of the bovids, had negligible or nondetectable carotenoid serum concentrations despite moderate intakes. Bovids accumulated only beta-carotene despite moderately high lutein + zeaxanthin intakes. Wild captive species demonstrated a wide variety of carotenoid accumulation patterns, which could be exploited to answer remaining questions concerning carotenoid metabolism and function.  (+info)

Accumulation of astaxanthin all-E, 9Z and 13Z geometrical isomers and 3 and 3' RS optical isomers in rainbow trout (Oncorhynchus mykiss) is selective. (2/814)

Concentrations of all-E-, 9Z- and 13Z- geometrical and (3R,3'R), (3R, 3'S) and (3S,3'S) optical isomers of astaxanthin were determined in rainbow trout liver, gut tissues, kidney, skin and blood plasma to evaluate their body distribution. Two cold-pelleted diets containing predominantly all-E-astaxanthin (36.9 mg/kg astaxanthin, 97% all-E-, 0.4% 9Z-, 1.5% 13Z-astaxanthin, and 1.1% other isomers, respectively) or a mixture of all-E- and Z-astaxanthins (35.4 mg/kg astaxanthin, 64% all-E-, 18.7% 9Z-, 12.3% 13Z-astaxanthin, and 2.0% other isomers, respectively), were fed to duplicate groups of trout for 69 d. Individual E/Z isomers were identified by VIS- and 1H-NMR-spectrometry, and quantified by high-performance liquid chromatography. Significantly higher total carotenoid concentration was observed in plasma of trout fed diets with all-E-astaxanthin (P < 0.05). The relative E/Z-isomer concentrations of plasma, skin and kidney were not significantly different among groups, whereas all-E-astaxanthin was higher in intestinal tissues and 13Z-astaxanthin was lower in liver of trout fed all-E-astaxanthin (P < 0.05). The relative amount of hepatic 13Z-astaxanthin (39-49% of total astaxanthin) was higher than in all other samples (P < 0.05). Synthetic, optically inactive astaxanthin was used in all experiments, and the determined dietary ratio between the 3R,3'R:3R, 3'S (meso):3S,3'S optical isomers was 25.3:49.6:25.1. The distribution of R/S-astaxanthin isomers in feces, blood, liver and fillet was similar to that in the diets. The ratio between (3S,3'S)- and (3R,3'R)-astaxanthin in the skin and posterior kidney was ca. 2:1 and 3:1, respectively, regardless of dietary E/Z-astaxanthin composition. The results show that geometrical and optical isomers of astaxanthin are distributed selectively in different tissues of rainbow trout.  (+info)

Carotenoid intakes, assessed by dietary questionnaire, are associated with plasma carotenoid concentrations in an elderly population. (3/814)

High intakes of fruits and vegetables and of carotenoids are associated with a lower risk for a variety of chronic diseases. It is therefore important to test the validity of dietary questionnaires that assess these intakes. We compared intakes of five carotenoids, as calculated from responses to the Willett 126-item food-frequency questionnaire, with corresponding biochemical measures. Subjects included 346 women and 201 men, aged 67-93 y, in the Framingham Heart Study. Unadjusted correlations were higher among women than men as follows: alpha-carotene 0.33 and 0.18, beta-carotene, 0.36 and 0.25; beta-cryptoxanthin, 0.44 and 0.32; lycopene, 0.35 and 0.21; and lutein + zeaxanthin, 0.27 and 0.10, respectively. Adjustment for age, energy intake, body mass index (BMI, kg/m2), plasma cholesterol concentrations and smoking reduced the gender differences, respectively, to the following: alpha-carotene 0.30 and 0.28; beta-carotene, 0.34 and 0.31; beta-cryptoxanthin, 0.45 and 0.36; lycopene, 0.36 and 0.31; and lutein + zeaxanthin, 0.24 and 0.14. Plots of adjusted mean plasma carotenoid concentration by quintile of respective carotenoid intake show apparent greater responsiveness among women, compared with men, to dietary intake of alpha- and beta-carotene and beta-cryptoxanthin, but similar blood-diet relationships for lycopene and lutein + zeaxanthin. Reported daily intake of fruits and vegetables correlated most strongly with plasma beta-cryptoxanthin and beta-carotene among women and with plasma alpha- and beta-carotene among men. With the exception of lutein + zeaxanthin, this dietary questionnaire does provide reasonable rankings of carotenoid status among elderly subjects, with the strongest correlations for beta-cryptoxanthin. Appropriate adjustment of confounders is necessary to clarify these associations among men.  (+info)

Paracoccus carotinifaciens sp. nov., a new aerobic gram-negative astaxanthin-producing bacterium. (4/814)

The strain E-396T, isolated from soil, was Gram-negative, aerobic, orange-pigmented, rod-shaped, motile by peritrichous flagella and astaxanthin-producing. This organism produced carotenoids, mainly astaxanthin, and did not produce bacteriochlorophyll. The ubiquinone system was Q-10. Analysis of the 16S rRNA sequence of strain E-396T showed it to be a member of the alpha-3 subclass of the Proteobacteria, forming a cluster with the species of the genus Paracoccus. On the basis of the production of orange pigments and motility by peritrichous flagella, together with DNA-DNA reassociation data, it is concluded that the new isolate should be classified into a new species of the genus Paracoccus, Paracoccus carotinifaciens sp. nov. The type strain is E-396T (= IFO 16121T).  (+info)

Comparison of serum carotenoid responses between women consuming vegetable juice and women consuming raw or cooked vegetables. (5/814)

The objective of this study was to examine serum concentrations of alpha-carotene, beta-carotene, lutein, lycopene, and beta-cryptoxanthin due to consumption of vegetable juice versus raw or cooked vegetables. Subjects included female breast cancer patients who had undergone surgical resection and who were enrolled in a feasibility study for a trial examining the influence of diet on breast cancer recurrence. A high-vegetable, low-fat diet was the focus of the intervention, and some of the subjects were specifically encouraged to consume vegetable juice. At 12 months, blood samples were collected and analyzed for carotenoid concentrations via high-performance liquid chromatography methodology. Matched analysis and paired t test were conducted on two groups: those who consumed vegetable juice (the juice group) and those who consumed raw or cooked vegetables (no juice group). Serum concentrations of alpha-carotene and lutein were significantly higher in the vegetable juice group than in the raw or cooked vegetable group (P < 0.05 and P = 0.05, respectively). Paired t test analysis did not demonstrate a significant difference in serum values of beta-carotene, lycopene, and beta-cryptoxanthin between subjects consuming juice and those not consuming any juice. These results suggest that alpha-carotene and lutein appear to be more bioavailable in the juice form than in raw or cooked vegetables. Therefore, the food form consumed may contribute to the variability in serum carotenoid response to vegetable and fruit interventions in clinical studies.  (+info)

Characterization of metabolites of astaxanthin in primary cultures of rat hepatocytes. (6/814)

The metabolism of the nonprovitamin A carotenoid astaxanthin was investigated in primary cultures of rat hepatocytes. In a time course study based on HPLC and gas chromatography-mass spectrometry analyses, one main metabolite, (rac)-3-hydroxy-4-oxo-beta-ionone, was found. This metabolite was conjugated mainly into glucuronides, as demonstrated by glusulase treatment of the conjugates under sulfatase-inhibiting conditions. Within 24 h more than 50% astaxanthin was metabolized and conjugated. Deconjugation of the polar conjugates with glusulase and analyses with HPLC and gas chromatography-mass spectrometry identified two metabolites, (rac)-3-hydroxy-4-oxo-beta-ionone and its reduced form (rac)-3-hydroxy-4-oxo-7,8-dihydro-beta-ionone, indicating that the former was reduced in the conjugated form. We confirmed that the ketocarotenoid astaxanthin induces xenobiotic-metabolizing enzymes in rat liver in vivo. However, there were no differences in the metabolism of astaxanthin in cultured hepatocytes from rats that were pretreated with astaxanthin and, thus, with induced cytochrome P-450 systems compared with control hepatocytes. Neither liver microsomes from astaxanthin-pretreated nor control rats metabolized astaxanthin. These results indicated that the cytochrome P-450 enzymes were not involved in the metabolism of astaxanthin in rat hepatocytes. We conclude that astaxanthin was metabolized in primary cultures of rat hepatocytes into (rac)-3-hydroxy-4-oxo-beta-ionone and its reduced form (rac)-3-hydroxy-4-oxo-7,8-dihydro-beta-ionone independent of the xenobiotic-metabolizing enzymes induced by astaxanthin.  (+info)

Determination of the stoichiometry and strength of binding of xanthophylls to the photosystem II light harvesting complexes. (7/814)

Xanthophylls have a crucial role in the structure and function of the light harvesting complexes of photosystem II (LHCII) in plants. The binding of xanthophylls to LHCII has been investigated, particularly with respect to the xanthophyll cycle carotenoids violaxanthin and zeaxanthin. It was found that most of the violaxanthin pool was loosely bound to the major complex and could be removed by mild detergent treatment. Gentle solubilization of photosystem II particles and thylakoids allowed the isolation of complexes, including a newly described oligomeric preparation, enriched in trimers, that retained all of the in vivo violaxanthin pool. It was estimated that each LHCII monomer can bind at least one violaxanthin. The extent to which different pigments can be removed from LHCII indicated that the relative strength of binding was chlorophyll b > neoxanthin > chlorophyll a > lutein > zeaxanthin > violaxanthin. The xanthophyll binding sites are of two types: internal sites binding lutein and peripheral sites binding neoxanthin and violaxanthin. In CP29, a minor LHCII, both a lutein site and the neoxanthin site can be occupied by violaxanthin. Upon activation of the violaxanthin de-epoxidase, the highest de-epoxidation state was found for the main LHCII component and the lowest for CP29, suggesting that only violaxanthin loosely bound to LHCII is available for de-epoxidation.  (+info)

Direct observation of the (forbidden) S1 state in carotenoids. (8/814)

Carotenoids are involved in a variety of biological functions, yet the underlying mechanisms are poorly understood, in part because of the long-standing difficulty in assigning the location of the first excited (S1) state. Here, we present a method for determining the energy of the forbidden S1 state, on the basis of ultrafast spectroscopy of the short lived level. Femtosecond transient absorption spectra and kinetics of the S1 --> S2 transition revealed the location of the intermediate level in two carotenoid species involved in the xanthophyll cycle, zeaxanthin and violaxanthin, and yielded surprising implications regarding the mechanism of photoregulation in photosynthesis.  (+info)

Xanthophylls are a type of pigment known as carotenoids, which are naturally occurring in various plants and animals. They are characterized by their yellow to orange color and play an important role in photosynthesis. Unlike other carotenoids, xanthophylls contain oxygen in their chemical structure.

In the context of human health, xanthophylls are often studied for their potential antioxidant properties and their possible role in reducing the risk of age-related macular degeneration (AMD), a leading cause of vision loss in older adults. The two main dietary sources of xanthophylls are lutein and zeaxanthin, which are found in green leafy vegetables, such as spinach and kale, as well as in other fruits and vegetables.

It's important to note that while a healthy diet rich in fruits and vegetables has many benefits for overall health, including eye health, more research is needed to fully understand the specific role of xanthophylls in preventing or treating diseases.

Lutein is a type of carotenoid, specifically a xanthophyll, that is naturally present in many fruits and vegetables. It is considered a dietary antioxidant with potential health benefits for the eyes. Lutein is not a vitamin, but it is often grouped with vitamins and minerals because of its importance to human health.

In the eye, lutein is selectively accumulated in the macula, a small area in the center of the retina responsible for sharp, detailed vision. It helps filter harmful blue light and protects the eye from oxidative damage, which may help maintain eye health and reduce the risk of age-related macular degeneration (AMD), a leading cause of blindness in older adults.

It is important to note that lutein is not produced by the human body and must be obtained through dietary sources or supplements. Foods rich in lutein include dark leafy greens, such as spinach and kale, as well as other fruits and vegetables, such as corn, orange pepper, and egg yolk.

Carotenoids are a class of pigments that are naturally occurring in various plants and fruits. They are responsible for the vibrant colors of many vegetables and fruits, such as carrots, pumpkins, tomatoes, and leafy greens. There are over 600 different types of carotenoids, with beta-carotene, alpha-carotene, lycopene, lutein, and zeaxanthin being some of the most well-known.

Carotenoids have antioxidant properties, which means they can help protect the body's cells from damage caused by free radicals. Some carotenoids, such as beta-carotene, can be converted into vitamin A in the body, which is important for maintaining healthy vision, skin, and immune function. Other carotenoids, such as lycopene and lutein, have been studied for their potential role in preventing chronic diseases, including cancer and heart disease.

In addition to being found in plant-based foods, carotenoids can also be taken as dietary supplements. However, it is generally recommended to obtain nutrients from whole foods rather than supplements whenever possible, as food provides a variety of other beneficial compounds that work together to support health.

Beta-carotene is a type of carotenoid, which is a pigment found in plants that gives them their vibrant colors. It is commonly found in fruits and vegetables, such as carrots, sweet potatoes, and spinach.

Beta-carotene is converted into vitamin A in the body, which is an essential nutrient for maintaining healthy vision, immune function, and cell growth. It acts as an antioxidant, helping to protect cells from damage caused by free radicals.

According to the medical definition, beta-carotene is a provitamin A carotenoid that is converted into vitamin A in the body. It has a variety of health benefits, including supporting eye health, boosting the immune system, and reducing the risk of certain types of cancer. However, it is important to note that excessive consumption of beta-carotene supplements can lead to a condition called carotenemia, which causes the skin to turn yellow or orange.

Chlorophyll binding proteins, also known as light-harvesting complexes (LHCs), are a type of protein found in the chloroplasts of plants, algae, and cyanobacteria. They play a crucial role in photosynthesis by binding to and helping to absorb light energy, which is then used to power the conversion of carbon dioxide and water into oxygen and glucose.

Chlorophyll binding proteins are composed of several subunits that contain both protein and chlorophyll molecules. The chlorophyll molecules are bound to the protein subunits in a way that allows them to absorb light energy most efficiently. When light is absorbed by the chlorophyll, it excites the electrons in the chlorophyll molecule, which then transfer the energy to other molecules in the photosynthetic apparatus.

There are several different types of chlorophyll binding proteins, each with slightly different properties and functions. Some are involved in capturing light energy for use in photosystem I, while others are involved in photosystem II. Additionally, some chlorophyll binding proteins are found in the thylakoid membranes of the chloroplasts, while others are located in the stroma.

Overall, chlorophyll binding proteins are essential components of the photosynthetic process, allowing plants and other organisms to harness the energy of the sun to power their metabolic reactions.

Photosystem II Protein Complex is a crucial component of the photosynthetic apparatus in plants, algae, and cyanobacteria. It is a multi-subunit protein complex located in the thylakoid membrane of the chloroplasts. Photosystem II plays a vital role in light-dependent reactions of photosynthesis, where it absorbs sunlight and uses its energy to drive the oxidation of water molecules into oxygen, electrons, and protons.

The protein complex consists of several subunits, including the D1 and D2 proteins, which form the reaction center, and several antenna proteins that capture light energy and transfer it to the reaction center. Photosystem II also contains various cofactors, such as pigments (chlorophylls and carotenoids), redox-active metal ions (manganese and calcium), and quinones, which facilitate the charge separation and electron transfer processes during photosynthesis.

Photosystem II Protein Complex is responsible for the initial charge separation event in photosynthesis, which sets off a series of redox reactions that ultimately lead to the reduction of NADP+ to NADPH and the synthesis of ATP, providing energy for the carbon fixation reactions in the Calvin cycle. Additionally, Photosystem II Protein Complex is involved in oxygen evolution, contributing to the Earth's atmosphere's oxygen levels and making it an essential component of global carbon fixation and oxygen production.

Canthaxanthin is a type of carotenoid, which is a class of pigments that are naturally occurring in certain plants and animals. It has a yellow-to-reddish color and is used as a food additive (coloring agent) and as a dietary supplement. In the medical field, canthaxanthin has been studied for its potential effects on skin conditions such as sun sensitivity and keratosis; however, its use in these contexts is not widely accepted or recommended due to limited evidence of effectiveness and potential safety concerns.

Facilitated diffusion is a type of passive transport that involves the movement of molecules or ions across a biological membrane with the assistance of a transport protein. Unlike simple diffusion, which occurs spontaneously down a concentration gradient, facilitated diffusion allows for the movement of substances against a concentration gradient, although it does not directly consume energy.

In facilitated diffusion, the transport protein binds to the substance (also known as the solute) on one side of the membrane and then changes shape, releasing the solute on the other side. This process can increase the rate of diffusion by providing a more efficient pathway for the solute to move through the membrane.

Examples of substances that use facilitated diffusion include glucose, amino acids, and ions such as sodium and potassium. These substances are too large or too polar to pass through the hydrophobic interior of the lipid bilayer that makes up the cell membrane, so they rely on transport proteins to help them move across the membrane.

It's important to note that facilitated diffusion is a passive process and does not require energy input from the cell. However, it is a regulated process, as the number of transport proteins in the membrane can be adjusted to control the rate of solute movement.

Light-harvesting protein complexes are specialized structures in photosynthetic organisms, such as plants, algae, and some bacteria, that capture and transfer light energy to the reaction centers where the initial chemical reactions of photosynthesis occur. These complexes consist of proteins and pigments (primarily chlorophylls and carotenoids) arranged in a way that allows them to absorb light most efficiently. The absorbed light energy is then converted into electrical charges, which are transferred to the reaction centers for further chemical reactions leading to the production of organic compounds and oxygen. The light-harvesting protein complexes play a crucial role in initiating the process of photosynthesis and optimizing its efficiency by capturing and distributing light energy.

Chlorophyll is a green pigment found in the chloroplasts of photosynthetic plants, algae, and some bacteria. It plays an essential role in light-dependent reactions of photosynthesis by absorbing light energy, primarily from the blue and red parts of the electromagnetic spectrum, and converting it into chemical energy to fuel the synthesis of carbohydrates from carbon dioxide and water. The structure of chlorophyll includes a porphyrin ring, which binds a central magnesium ion, and a long phytol tail. There are several types of chlorophyll, including chlorophyll a and chlorophyll b, which have distinct absorption spectra and slightly different structures. Chlorophyll is crucial for the process of photosynthesis, enabling the conversion of sunlight into chemical energy and the release of oxygen as a byproduct.

An Eye Bank is an organization that collects, stores, and distributes donated human eyes for corneal transplantation and other ocular medical research purposes. The eye bank's primary function is to ensure the quality of the donated tissue and make it available for those in need of sight-restoring procedures.

The cornea, the clear front part of the eye, can be surgically transplanted from a deceased donor to a recipient with corneal damage or disease, thereby improving or restoring their vision. The eye bank's role includes obtaining consent for donation, retrieving the eyes from the donor, evaluating the tissue for suitability, preserving it properly, and then allocating it to surgeons for transplantation.

Eye banks follow strict medical guidelines and adhere to ethical standards to ensure the safety and quality of the donated tissues. The process involves screening potential donors for infectious diseases and other conditions that may affect the quality or safety of the cornea. Once deemed suitable, the corneas are carefully removed, preserved in specific solutions, and stored until they are needed for transplantation.

In addition to corneal transplants, eye banks also support research and education in ophthalmology by providing human eye tissues for various studies aimed at advancing our understanding of eye diseases and developing new treatments.

Biological pigments are substances produced by living organisms that absorb certain wavelengths of light and reflect others, resulting in the perception of color. These pigments play crucial roles in various biological processes such as photosynthesis, vision, and protection against harmful radiation. Some examples of biological pigments include melanin, hemoglobin, chlorophyll, carotenoids, and flavonoids.

Melanin is a pigment responsible for the color of skin, hair, and eyes in animals, including humans. Hemoglobin is a protein found in red blood cells that contains a porphyrin ring with an iron atom at its center, which gives blood its red color and facilitates oxygen transport. Chlorophyll is a green pigment found in plants, algae, and some bacteria that absorbs light during photosynthesis to convert carbon dioxide and water into glucose and oxygen. Carotenoids are orange, yellow, or red pigments found in fruits, vegetables, and some animals that protect against oxidative stress and help maintain membrane fluidity. Flavonoids are a class of plant pigments with antioxidant properties that have been linked to various health benefits.

Photosynthetic Reaction Center (RC) Complex Proteins are specialized protein-pigment structures that play a crucial role in the primary process of light-driven electron transport during photosynthesis. They are present in the thylakoid membranes of cyanobacteria, algae, and higher plants.

The Photosynthetic Reaction Center Complex Proteins are composed of two major components: the light-harvesting complex (LHC) and the reaction center (RC). The LHC contains antenna pigments like chlorophylls and carotenoids that absorb sunlight and transfer the excitation energy to the RC. The RC is a multi-subunit protein complex containing cofactors such as bacteriochlorophyll, pheophytin, quinones, and iron-sulfur clusters.

When a photon of light is absorbed by the antenna pigments in the LHC, the energy is transferred to the RC, where it initiates a charge separation event. This results in the transfer of an electron from a donor molecule to an acceptor molecule, creating a flow of electrical charge and generating a transmembrane electrochemical gradient. The energy stored in this gradient is then used to synthesize ATP and reduce NADP+, which are essential for carbon fixation and other metabolic processes in the cell.

In summary, Photosynthetic Reaction Center Complex Proteins are specialized protein structures involved in capturing light energy and converting it into chemical energy during photosynthesis, ultimately driving the synthesis of ATP and NADPH for use in carbon fixation and other metabolic processes.

Thylakoids are membrane-bound structures located in the chloroplasts of plant cells and some protists. They are the site of the light-dependent reactions of photosynthesis, where light energy is converted into chemical energy in the form of ATP (adenosine triphosphate) and NADPH (nicotinamide adenine dinucleotide phosphate). Thylakoids have a characteristic stacked or disc-like structure, called grana, and are interconnected by unstacked regions called stroma lamellae. The arrangement of thylakoids in grana increases the surface area for absorption of light energy, allowing for more efficient photosynthesis.

The macula lutea, often simply referred to as the macula or fovea centralis, is a part of the eye that is responsible for central vision and color perception. It's located in the center of the retina, the light-sensitive tissue at the back of the eye. The macula contains a high concentration of pigments called xanthophylls, which give it a yellowish color and protect the photoreceptor cells in this area from damage by blue light.

The central part of the macula is called the fovea, which is a small depression that contains only cones, the photoreceptor cells responsible for color vision and high visual acuity. The fovea is surrounded by the parafovea and the perifovea, which contain both cones and rods, the photoreceptor cells responsible for low-light vision and peripheral vision.

Damage to the macula can result in a loss of central vision and color perception, a condition known as age-related macular degeneration (AMD), which is a leading cause of blindness in older adults. Other conditions that can affect the macula include macular edema, macular holes, and macular pucker.

Intramolecular lyases are a type of enzyme that catalyzes the breakdown of a molecule by removing a group of atoms from within the same molecule, creating a new chemical bond in the process. These enzymes specifically cleave a molecule through an intramolecular mechanism, meaning they act on a single substrate molecule. Intramolecular lyases are involved in various biological processes, such as DNA replication, repair, and recombination. They play a crucial role in maintaining the integrity of genetic material by removing or adding specific groups of atoms to DNA or RNA molecules.

'Equipment and Supplies' is a term used in the medical field to refer to the physical items and materials needed for medical care, treatment, and procedures. These can include a wide range of items, such as:

* Medical equipment: This includes devices and machines used for diagnostic, monitoring, or therapeutic purposes, such as stethoscopes, blood pressure monitors, EKG machines, ventilators, and infusion pumps.
* Medical supplies: These are consumable items that are used once and then discarded, such as syringes, needles, bandages, gowns, gloves, and face masks.
* Furniture and fixtures: This includes items such as hospital beds, examination tables, chairs, and cabinets that are used to create a functional medical space.

Having the right equipment and supplies is essential for providing safe and effective medical care. The specific items needed will depend on the type of medical practice or facility, as well as the needs of individual patients.

In the context of medical terminology, "light" doesn't have a specific or standardized definition on its own. However, it can be used in various medical terms and phrases. For example, it could refer to:

1. Visible light: The range of electromagnetic radiation that can be detected by the human eye, typically between wavelengths of 400-700 nanometers. This is relevant in fields such as ophthalmology and optometry.
2. Therapeutic use of light: In some therapies, light is used to treat certain conditions. An example is phototherapy, which uses various wavelengths of ultraviolet (UV) or visible light for conditions like newborn jaundice, skin disorders, or seasonal affective disorder.
3. Light anesthesia: A state of reduced consciousness in which the patient remains responsive to verbal commands and physical stimulation. This is different from general anesthesia where the patient is completely unconscious.
4. Pain relief using light: Certain devices like transcutaneous electrical nerve stimulation (TENS) units have a 'light' setting, indicating lower intensity or frequency of electrical impulses used for pain management.

Without more context, it's hard to provide a precise medical definition of 'light'.

Polymyxins are a group of antibiotics derived from the bacterium Paenibacillus polymyxa. They consist of polymyxin B and polymyxin E (also known as colistin), which have similar structures and mechanisms of action. Polymyxins bind to the lipopolysaccharide component of the outer membrane of Gram-negative bacteria, causing disruption of the membrane and ultimately leading to bacterial cell death. These antibiotics are primarily used to treat serious infections caused by multidrug-resistant Gram-negative bacteria, but their use is limited due to potential nephrotoxicity and neurotoxicity.

I believe there may be a slight misunderstanding in your question. "Plant leaves" are not a medical term, but rather a general biological term referring to a specific organ found in plants.

Leaves are organs that are typically flat and broad, and they are the primary site of photosynthesis in most plants. They are usually green due to the presence of chlorophyll, which is essential for capturing sunlight and converting it into chemical energy through photosynthesis.

While leaves do not have a direct medical definition, understanding their structure and function can be important in various medical fields, such as pharmacognosy (the study of medicinal plants) or environmental health. For example, certain plant leaves may contain bioactive compounds that have therapeutic potential, while others may produce allergens or toxins that can impact human health.

Photosynthesis is not strictly a medical term, but it is a fundamental biological process with significant implications for medicine, particularly in understanding energy production in cells and the role of oxygen in sustaining life. Here's a general biological definition:

Photosynthesis is a process by which plants, algae, and some bacteria convert light energy, usually from the sun, into chemical energy in the form of organic compounds, such as glucose (or sugar), using water and carbon dioxide. This process primarily takes place in the chloroplasts of plant cells, specifically in structures called thylakoids. The overall reaction can be summarized as:

6 CO2 + 6 H2O + light energy → C6H12O6 + 6 O2

In this equation, carbon dioxide (CO2) and water (H2O) are the reactants, while glucose (C6H12O6) and oxygen (O2) are the products. Photosynthesis has two main stages: the light-dependent reactions and the light-independent reactions (Calvin cycle). The light-dependent reactions occur in the thylakoid membrane and involve the conversion of light energy into ATP and NADPH, which are used to power the Calvin cycle. The Calvin cycle takes place in the stroma of chloroplasts and involves the synthesis of glucose from CO2 and water using the ATP and NADPH generated during the light-dependent reactions.

Understanding photosynthesis is crucial for understanding various biological processes, including cellular respiration, plant metabolism, and the global carbon cycle. Additionally, research into artificial photosynthesis has potential applications in renewable energy production and environmental remediation.

Mixed Function Oxygenases (MFOs) are a type of enzyme that catalyze the addition of one atom each from molecular oxygen (O2) to a substrate, while reducing the other oxygen atom to water. These enzymes play a crucial role in the metabolism of various endogenous and exogenous compounds, including drugs, carcinogens, and environmental pollutants.

MFOs are primarily located in the endoplasmic reticulum of cells and consist of two subunits: a flavoprotein component that contains FAD or FMN as a cofactor, and an iron-containing heme protein. The most well-known example of MFO is cytochrome P450, which is involved in the oxidation of xenobiotics and endogenous compounds such as steroids, fatty acids, and vitamins.

MFOs can catalyze a variety of reactions, including hydroxylation, epoxidation, dealkylation, and deamination, among others. These reactions often lead to the activation or detoxification of xenobiotics, making MFOs an important component of the body's defense system against foreign substances. However, in some cases, these reactions can also produce reactive intermediates that may cause toxicity or contribute to the development of diseases such as cancer.

Photosystem I Protein Complex, also known as PsaA/B-Protein or Photosystem I reaction center, is a large protein complex found in the thylakoid membrane of plant chloroplasts and cyanobacteria. It plays a crucial role in light-dependent reactions of photosynthesis, where it absorbs light energy and converts it into chemical energy in the form of NADPH.

The complex is composed of several subunits, including PsaA and PsaB, which are the core components that bind to chlorophyll a and bacteriochlorophyll a pigments. These pigments absorb light energy and transfer it to the reaction center, where it is used to drive the electron transport chain and generate a proton gradient across the membrane. This gradient is then used to produce ATP, which provides energy for the carbon fixation reactions in photosynthesis.

Photosystem I Protein Complex is also involved in cyclic electron flow, where electrons are recycled within the complex to generate additional ATP without producing NADPH. This process helps regulate the balance between ATP and NADPH production in the chloroplast and optimizes the efficiency of photosynthesis.

Pharmacology is the branch of medicine and biology concerned with the study of drugs, their actions, and their uses. It involves understanding how drugs interact with biological systems to produce desired effects, as well as any adverse or unwanted effects. This includes studying the absorption, distribution, metabolism, and excretion of drugs (often referred to as ADME), the receptors and biochemical pathways that drugs affect, and the therapeutic benefits and risks of drug use. Pharmacologists may also be involved in the development and testing of new medications.

Neomycin is an antibiotic drug derived from the bacterium Streptomyces fradiae. It belongs to the class of aminoglycoside antibiotics and works by binding to the 30S subunit of the bacterial ribosome, thereby inhibiting protein synthesis and leading to bacterial cell death. Neomycin is primarily used topically (on the skin or mucous membranes) due to its poor absorption into the bloodstream when taken orally. It is effective against a wide range of gram-positive and gram-negative bacteria. Medical definitions for Neomycin include:

1. An antibiotic (aminoglycoside) derived from Streptomyces fradiae, used primarily for topical application in the treatment of superficial infections, burns, and wounds. It is not usually used systemically due to its potential ototoxicity and nephrotoxicity.
2. A medication (generic name) available as a cream, ointment, solution, or powder, often combined with other active ingredients such as bacitracin and polymyxin B for broader-spectrum antibacterial coverage. Neomycin is used to treat various skin conditions, including eczema, dermatitis, and minor cuts or abrasions.
3. A component of some over-the-counter products (e.g., ear drops, eye drops) intended for the treatment of external otitis, swimmer's ear, or bacterial conjunctivitis. It is crucial to follow the instructions carefully and avoid using neomycin-containing products for extended periods or in larger quantities than recommended, as this may increase the risk of antibiotic resistance and potential side effects.

In summary, Neomycin is an aminoglycoside antibiotic primarily used topically for treating various superficial bacterial infections due to its effectiveness against a wide range of gram-positive and gram-negative bacteria. It should be used cautiously and as directed to minimize the risk of side effects and antibiotic resistance.

'Arabidopsis' is a genus of small flowering plants that are part of the mustard family (Brassicaceae). The most commonly studied species within this genus is 'Arabidopsis thaliana', which is often used as a model organism in plant biology and genetics research. This plant is native to Eurasia and Africa, and it has a small genome that has been fully sequenced. It is known for its short life cycle, self-fertilization, and ease of growth, making it an ideal subject for studying various aspects of plant biology, including development, metabolism, and response to environmental stresses.

High-performance liquid chromatography (HPLC) is a type of chromatography that separates and analyzes compounds based on their interactions with a stationary phase and a mobile phase under high pressure. The mobile phase, which can be a gas or liquid, carries the sample mixture through a column containing the stationary phase.

In HPLC, the mobile phase is a liquid, and it is pumped through the column at high pressures (up to several hundred atmospheres) to achieve faster separation times and better resolution than other types of liquid chromatography. The stationary phase can be a solid or a liquid supported on a solid, and it interacts differently with each component in the sample mixture, causing them to separate as they travel through the column.

HPLC is widely used in analytical chemistry, pharmaceuticals, biotechnology, and other fields to separate, identify, and quantify compounds present in complex mixtures. It can be used to analyze a wide range of substances, including drugs, hormones, vitamins, pigments, flavors, and pollutants. HPLC is also used in the preparation of pure samples for further study or use.

Antioxidants are substances that can prevent or slow damage to cells caused by free radicals, which are unstable molecules that the body produces as a reaction to environmental and other pressures. Antioxidants are able to neutralize free radicals by donating an electron to them, thus stabilizing them and preventing them from causing further damage to the cells.

Antioxidants can be found in a variety of foods, including fruits, vegetables, nuts, and grains. Some common antioxidants include vitamins C and E, beta-carotene, and selenium. Antioxidants are also available as dietary supplements.

In addition to their role in protecting cells from damage, antioxidants have been studied for their potential to prevent or treat a number of health conditions, including cancer, heart disease, and age-related macular degeneration. However, more research is needed to fully understand the potential benefits and risks of using antioxidant supplements.

Arabidopsis proteins refer to the proteins that are encoded by the genes in the Arabidopsis thaliana plant, which is a model organism commonly used in plant biology research. This small flowering plant has a compact genome and a short life cycle, making it an ideal subject for studying various biological processes in plants.

Arabidopsis proteins play crucial roles in many cellular functions, such as metabolism, signaling, regulation of gene expression, response to environmental stresses, and developmental processes. Research on Arabidopsis proteins has contributed significantly to our understanding of plant biology and has provided valuable insights into the molecular mechanisms underlying various agronomic traits.

Some examples of Arabidopsis proteins include transcription factors, kinases, phosphatases, receptors, enzymes, and structural proteins. These proteins can be studied using a variety of techniques, such as biochemical assays, protein-protein interaction studies, and genetic approaches, to understand their functions and regulatory mechanisms in plants.

"Plant proteins" refer to the proteins that are derived from plant sources. These can include proteins from legumes such as beans, lentils, and peas, as well as proteins from grains like wheat, rice, and corn. Other sources of plant proteins include nuts, seeds, and vegetables.

Plant proteins are made up of individual amino acids, which are the building blocks of protein. While animal-based proteins typically contain all of the essential amino acids that the body needs to function properly, many plant-based proteins may be lacking in one or more of these essential amino acids. However, by consuming a variety of plant-based foods throughout the day, it is possible to get all of the essential amino acids that the body needs from plant sources alone.

Plant proteins are often lower in calories and saturated fat than animal proteins, making them a popular choice for those following a vegetarian or vegan diet, as well as those looking to maintain a healthy weight or reduce their risk of chronic diseases such as heart disease and cancer. Additionally, plant proteins have been shown to have a number of health benefits, including improving gut health, reducing inflammation, and supporting muscle growth and repair.

The xanthophyll cycle involves the enzymatic removal of epoxy groups from xanthophylls (e.g. violaxanthin, antheraxanthin, ... Carotenes are usually more orange in color than xanthophylls.) Xanthophylls present their oxygen either as hydroxyl groups and/ ... As both are carotenoids, xanthophylls and carotenes are similar in structure, but xanthophylls contain oxygen atoms while ... Like other carotenoids, xanthophylls are found in highest quantity in the leaves of most green plants, where they act to ...
In plants, the xanthophyll lutein is the most abundant carotenoid and its role in preventing age-related eye disease is ... Xanthophylls are often yellow, giving their class name. Carotenoids also participate in different types of cell signaling. They ... They are known as xanthophylls. Their color, ranging from pale yellow through bright orange to deep red, is directly related to ... Over 1,100 identified carotenoids can be further categorized into two classes - xanthophylls (which contain oxygen) and ...
... is a xanthophyll. Xanthophyll pigments are photoprotective pigments that help protect cells from harmful effects ... It gives rise to the xanthophylls diatoxanthin and dinoxanthin. Diadinoxanthin is a plastid pigment. Plastid pigments include ... Accessory pigment Algae Carotenoid Diatom Diatoxanthin Dinoxanthin Photoprotection Phytoplankton Xanthophyll Adl, Sina M.; et ... of too much light energy (light saturation). It is present in cells along with diatoxanthin (another xanthophyll). ...
Carotenoids containing some oxygen are known as xanthophylls. The two ends of the β-carotene molecule are structurally ... as does the xanthophyll carotenoid β-cryptoxanthin. All other carotenoids, including lycopene, have no beta-ring and thus no ... the xanthophylls, which contain oxygen and thus are less chemically hydrophobic). The discovery of carotene from carrot juice ... distinguishing it from the similar but oxygenated xanthophyll, C40H56O2. With Heinrich Escher, in 1910, lycopene was isolated ...
Some unique xanthophylls are also present in this seaweed. The landlady's wig could be confused with Cordylecladia erecta but ...
They are split into two classes, xanthophylls and carotenes. Xanthophylls are carotenoids with molecules containing oxygen, ...
Xanthophylls Chlorophyll a Chlorophyll b Chlorophyll a is found in all chloroplasts, as well as their cyanobacterial ancestors ... β-carotene is a bright red-orange carotenoid found in nearly all chloroplasts, like chlorophyll a. Xanthophylls, especially the ... and at least one dinophyte-unique xanthophyll (peridinin, dinoxanthin, or diadinoxanthin), giving many a golden-brown color. ...
See xanthophyll cycle for this topic. Animals obtain lutein by ingesting plants. In the human retina, lutein is absorbed from ... In green plants, xanthophylls act to modulate light energy and serve as non-photochemical quenching agents to deal with triplet ... This xanthophyll, like its sister compound zeaxanthin, has primarily been used in food and supplement manufacturing as a ... Lutein is synthesized only by plants, and like other xanthophylls is found in high quantities in green leafy vegetables such as ...
xanthophyll A yellow-colored photosynthetic pigment. xylem A type of plant tissue responsible for the transport of water from ...
... is a carotenoid and xanthophyll. In plants, it is an intermediate in the biosynthesis of the plant hormone abscisic ... It is a major xanthophyll found in green leafy vegetables such as spinach. Bouvier, Florence; D'harlingue, Alain; Backhaus, ...
The antenna pigments are predominantly chlorophyll b, xanthophylls, and carotenes. Chlorophyll a is known as the core pigment. ...
Strain SD212 and Combinatorial Biosynthesis of New or Rare Xanthophylls". Applied and Environmental Microbiology. 71 (8): 4286- ... Strain SD212 and Combinatorial Biosynthesis of New or Rare Xanthophylls". Applied and Environmental Microbiology. 71 (8): 4286- ...
... see xanthophyll). Xanthophylls such as zeaxanthin are found in highest quantity in the leaves of most green plants, where they ... Zeaxanthin is one of the most common carotenoids in nature, and is used in the xanthophyll cycle. Synthesized in plants and ... Zeaxanthin is one of the two primary xanthophyll carotenoids contained within the retina of the eye. Zeaxanthin supplements are ... Koo, E; Neuringer, M; Sangiovanni, J. P. (2014). "Macular xanthophylls, lipoprotein-related genes, and age-related macular ...
It is a xanthophyll cycle pigment, an oil-soluble alcohol within the xanthophyll subgroup of carotenoids. Antheraxanthin is ... The xanthophyll pool, or total xanthophyll cycle pigment levels are sometimes abbreviated as "VAZ" in scientific literature. " ... In the xanthophyll cycle, specific carotenoid pigments are transformed via enzymatic reactions into either more or less ... Xanthophyll cycle reactions, where antheraxanthin is an intermediate stage, are usually responses to changes in light or ...
... is a xanthophyll, with formula C40H54O. It is found in some cyanobacteria. It is synthesized from β-carotene by the ...
Xanthophyll absorbs well at 400-530 nm. However, none of the pigments[citation needed] absorbs well in the green-yellow region ... List of photosynthetic pigments (in order of increasing polarity): Carotene: an orange pigment Xanthophyll: a yellow pigment ...
... is a xanthophyll, with formula C42H58O6. It is found as an accessory pigment in the chloroplasts of brown algae and ... Xanthophylls are a subset of carotenoids, identified by the fact that they are oxygenated either as hydroxyl groups or as ... Fucoxanthin is a xanthophyll that contributes more than 10% of the estimated total production of carotenoids in nature. It is ...
Algae also use chlorophyll, but various other pigments are present, such as phycocyanin, carotenes, and xanthophylls in green ... Besides chlorophyll, plants also use pigments such as carotenes and xanthophylls. ...
The genes code for proteins that associate with chlorophyll and xanthophylls. This association aids the absorption of sunlight ...
Light stress can be tolerated by dissipating excess energy as heat through the xanthophyll cycle. Violaxanthin and zeaxanthin ... are carotenoid molecules within the chloroplasts called xanthophylls. Under normal conditions, violaxanthin channels light to ...
Xanthophylls are another group of tetraterpene pigments distributed widely in nature. Davis, Edward M.; Croteau, Rodney (2000 ...
It is a member of the class of carotenoids known as xanthophylls. In a pure form, β-cryptoxanthin is a red crystalline solid ...
Strain H. H. (1949). "Hopkinsiaxanthin, a xanthophyll of the sea slug Hopkinsia rosacea". Biological Bulletin 97(1):206-209. ...
On our knowledge of xanthophyll]. Zeitschrift für Physiologische Chemie. 197 (1-4): 141-160. doi:10.1515/bchm2.1931.197.1-4.141 ...
... is a type of xanthophyll found in dinoflagellates. This compound is a potential antioxidant and may help to protect ...
As a monocyclic xanthophyll, it has a yellowish color. It is required for normal cell wall structure and thylakoid organization ...
Mijts BN, Lee PC, Schmidt-Dannert C (April 2005). "Identification of a carotenoid oxygenase synthesizing acyclic xanthophylls: ...
... is a natural red dye of the xanthophyll class. As a food coloring, it has the E number E160c(ii). Capsorubin is a ...
They also produce it from β-cryptoxanthin, a type of xanthophyll. These carotenoids must be obtained from plants or other ... The (R)-enantiomer is to be expected if 3-hydroxyretinal is produced directly from xanthophyll carotenoids. Cyclorrhaphans, ... which derive from conversion from other xanthophylls. Living organisms produce retinal by irreversible oxidative cleavage of ...
Dimier C, Giovanni S, Ferdinando T, Brunet C (April 2009). "Comparative Ecophysiology of the Xanthophyll Cycle in Six Marine ...
The xanthophyll cycle involves the enzymatic removal of epoxy groups from xanthophylls (e.g. violaxanthin, antheraxanthin, ... Carotenes are usually more orange in color than xanthophylls.) Xanthophylls present their oxygen either as hydroxyl groups and/ ... As both are carotenoids, xanthophylls and carotenes are similar in structure, but xanthophylls contain oxygen atoms while ... Like other carotenoids, xanthophylls are found in highest quantity in the leaves of most green plants, where they act to ...
The accumulation of xanthophylls in flowers of marigold (Tagetes) species cultivated under conditions of the Belgorod region ... Deineka, V.I., Sorokopudov, V.N., Deineka, L.A. et al. Flowers of marigold (Tagetes) species as a source of xanthophylls. Pharm ... The accumulation of xanthophylls in flowers of marigold (Tagetes) species cultivated under conditions of the Belgorod region ... It is shown that more than 90% of xanthophylls in flowers are retained upon drying and the content of lutein diesters in the ...
where to buy 127-40-2(Xanthophyll).Also offer free database of 127-40-2(Xanthophyll) including MSDS sheet(poisoning, toxicity, ... Xanthophyll;all-trans-(+)-Xanthophyll;all-trans-Lutein;all-trans-Xanthophyll;trans-Lutein;Lutein extract;Lutein;Marigold Flower ... Xanthophyll , its cas register number is 127-40-2. It also can be called Xanthophyll ; and alpha-Carotene-3,3-diol . Its ... Structure of Xanthophyll (CAS NO.127-40-2):. IUPAC Name: (1R,4R)-4-[(1E,3E,5E,7E,9E,11E,13E,15E,17E)-18-[(4R)-4-Hydroxy-2,6,6- ...
Xanthophyll. Ans: Hint: Flower production is based on photoperiod.Complete answer: Pigments are coloured substances or ... Xanthophyll: These are oxygen containing carotenoid pigments. They provide various shades of yellow, orange, red hues of ...
Overview of Diet-Gene Interactions and the Example of Xanthophylls Journal Article *Overview ...
Xanthophylls. Median. 1.25 vs. 1.54. 1.09 vs. 1.04. 2.03 vs. 2.44. ß [CI]-model 1. −0.35 [−0.71; 0.002]. 0.051. −0.045 [−0.51; ... Xanthophylls. Median. 2.04 vs. 1.09. 2.44 vs. 1.04. 2.03 vs. 1.09. ß [CI]-model 1. 1.00 [0.67; 1.33]. ,0.00001. 1.27 [0.81; ... Table 2. Differences in total carotenoid, carotenes and xanthophylls plasma concentrations (μmol/L) between F&V consumption ... Table 2. Differences in total carotenoid, carotenes and xanthophylls plasma concentrations (μmol/L) between F&V consumption ...
Saccharomyces cerevisiae is an important platform organism for synthesis of chemicals and fuels. However, the promoters used in most pathway engineering studies in S. cerevisiae have not been characterized and compared in parallel under multiple conditions that are routinely operated in laboratory a …
meso-Zeaxanthin (3R,3´S-Zeaxanthin) is a xanthophyll carotenoid, as it contains oxygen and hydrocarbons, and is one of the ... another xanthophyll carotenoid found in the human diet),[5][6] but this work (limited to animal studies) has since been refuted ... "Macular response to supplementation with differing xanthophyll formulations in subjects with and without age-related macular ...
Dynamic xanthophyll cycle (XC) related non-photochemical quenching (NPQd, also called qE) is present in most phototrophs. It ... Lacour Thomas, Robert Elise, Lavaud Johann (2023). Sustained xanthophyll pigments-related photoprotective NPQ is involved in ... Sustained xanthophyll pigments-related photoprotective NPQ is involved in photoinhibition in the haptophyte Tisochrysis lutea. ... Dynamic xanthophyll cycle (XC) related non-photochemical quenching (NPQd, also called qE) is present in most phototrophs. It ...
Item Specifications Appearance Free flow yellow powder Xanthophylls ≥ 4% Pb,ppm ≤10.0 As,ppm ≤3.0 Drying Loss,% ≤10.0 ... Marigold Extract is a dry stabilized source of natural xanthophylls (Lutein) extracted from Marigold flowers (Tagetes erecta). ... It contains different xanthophylls level with approx. 80% of trans-lutein, which bring more orange color to broiler skin and ...
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Postmenopausal women could benefit from an increase in anthocyanins and xanthophylls intake, through the consumption of fruits ... xanthophylls, or both groups of bioactives together in postmenopausal women. Seventy-two postmenopausal women were randomized ... and a third group consuming a combination of anthocyanins and xanthophylls in the same amounts (Group A+X). Non-targeted ... Postmenopausal women could benefit from an increase in anthocyanins and xanthophylls intake, through the consumption of fruits ...
van de Poll, W. H., Buma, A. G. J., Visser, R. J. W., Janknegt, P. J., Villafane, V. E., & Helbling, E. W. (2010). Xanthophyll ... Synthesis of xanthophyll cycle pigments occurred in both species, and was faster for D. tertiolecta during PAR + UV than during ... Synthesis of xanthophyll cycle pigments occurred in both species, and was faster for D. tertiolecta during PAR + UV than during ... Synthesis of xanthophyll cycle pigments occurred in both species, and was faster for D. tertiolecta during PAR + UV than during ...
Flavonoids: narnigenina, hesperidin, xanthophylls. *Coumarins: bergapten, limetina. More information on lime. Properties of ...
... xanthophylls and lutein are what turns them yellow; and, high fiber is what makes them white. How to eat them: Raw is best (as ...
Lutein is a member of the group of carotenoids called xanthophylls. Consuming lutein can help people prevent damage to ...
Indeed, it is well-known that esterified xanthophylls are hydrolyzed during digestion and absorbed as free xanthophylls [17,156 ... To evaluate the effect of paprika xanthophylls on non-UV-irradiated skin, facial skin colour (L*, a*, b*), TEWL and SCH values ... Astaxanthin is a xanthophyll biosynthesized by microalgae (Haematococcus pluvialis, Chlorella zofingiensis, and Chlorococcum sp ... Wingerath, T.; Sies, H.; Stahl, W. Xanthophyll Esters in Human Skin. Arch. Biochem. Biophys. 1998, 355, 271-274. [Google ...
carotenoids, and xanthophylls, respectively). The show stoppers, the plants that contain anthocyanins, which reflect red, pink ...
Xanthophyll. HMDB. (3R,3r,6S)-4,5-DIDEHYDRO-5,6-dihydro-b,b-carotene-3,3-diol. HMDB. ...
Xanthophyll cycle plays a major role in protecting the photosynthetic apparatus from photo-oxidative stress (Latowski et al., ... Moreover, a different study showed that doubling the size of the xanthophyll pool led to increased resistance to high light and ... Havaux, M., DallOsto, L., Cuiné, S., Giuliano, G., Bassi, R. (2004). The effect of zeaxanthin as the only xanthophyll on the ... Latowski, D., Kuczyńska, P., Strzałka, K. (2011). Xanthophyll cycle-a mechanism protecting plants against oxidative stress. ...
XANTHOPHYLL DERIVATIVES. The present invention provides for xanthophyll derivatives and compositions comprising the xanthophyll ...
Several xanthophylls are found in the macular pigment in the eye where they may protect against macular degeneration. ...
There are over 600 known carotenoids which are broken down into 2 groups; Xanthophylls and Carotenes.. One of the most ... important carotenoids is the Xanthophyll group is the super antioxidant Astaxanthin. Astaxanthin is the most powerful known ...
Yatsuhashi H, Takumi H, Terada Y, Kuriki T. Effects of Oral Supplementation with Paprika Xanthophylls on Human Skin Moisture. J ...
... xanthophylls, triol triterpenes, flavonoids and volatiles. Chalchat and Cols (3) studied the essential oil of C. officinalis ...
Lutein is a xanthophyll and one of 600 known naturally occurring carotenoids. Lutein is synthesized only by plants and like ... other xanthophylls is found in high quantities in green leafy vegetables such as spinach, kale and yellow carrots. Lutein is ...
The potential role of dietary xanthophylls in cataract and age-related macular degeneration. J Am Coll Nutr 2000; 19 (5 Suppl ...
van Oort, B.; Roy, L. M.; Xu, P.; Lu, Y.; Karcher, D.; Bock, R.; Croce, R.: Revisiting the Role of Xanthophylls in ...
Whether higher xanthophyll levels in AMD are due to supplement use cannot be determined in this study.. DOI: 10.1016/j.xops. ... Associations among plasma xanthophylls and MPOV were assessed adjusting for age.. Main Outcome Measures: Age-related macular ... Macular and Plasma Xanthophylls Are Higher in Age-related Macular Degeneration than in Normal Aging: Alabama Study on Early Age ... An assumption that xanthophylls are low in AMD retina underlies supplementation strategies to reduce progression risk, which ...
A rise in the systemic level of total xanthophylls was observed at M1 for both groups. At M2, total xanthophylls were ... Arnold C, Winter L, Fröhlich K, Jentsch S, Dawczynski J, Jahreis G, Böhm V: Macular xanthophylls and ω-3 long-chain ... Eidenberger T: Process for the Manufacture of a Composition Containing at Least One Xanthophyll. 2009, patent US7812198 B2. ... Xanthophylls were quantified in plasma, as well as the HDL, non-HDL, and erythrocyte fractions at each study visit. Results: ...
  • As both are carotenoids, xanthophylls and carotenes are similar in structure, but xanthophylls contain oxygen atoms while carotenes are purely hydrocarbons, which do not contain oxygen. (wikipedia.org)
  • Like other carotenoids, xanthophylls are found in highest quantity in the leaves of most green plants, where they act to modulate light energy and perhaps serve as a non-photochemical quenching agent to deal with triplet chlorophyll (an excited form of chlorophyll),[citation needed] which is overproduced at high light levels in photosynthesis. (wikipedia.org)
  • Lutein is a member of the group of carotenoids called xanthophylls. (medicalnewstoday.com)
  • One of the most important carotenoids is the Xanthophyll group is the super antioxidant Astaxanthin. (vitacart.com)
  • Lutein is a xanthophyll and one of 600 known naturally occurring carotenoids. (disabled-world.com)
  • The start-up can produce algae-centered ingredients standardized to any bioactive compound or algae extract encompassing fucoxanthins , polysaccharides, xanthophylls , carotenoids, enzymes, and more. (prnewswire.com)
  • Many other organisms also contain accessory pigments, including other chlorophylls, carotenoids , and xanthophylls , which absorb other wavelengths in the visible spectrum. (fsu.edu)
  • Carotenoids and xanthophylls provide the yellow and brownish colors of the fall foliage display. (wvencyclopedia.org)
  • The same compounds that are responsible for the orange colour of carrots are the triggers for yellow, gold and orange leaf colours - carotenoids and xanthophylls,' the NCC website reads. (ctvnews.ca)
  • For example, the yellow color of chicken egg yolks, fat, and skin comes from ingested xanthophylls-primarily lutein, which is added to chicken feed for this purpose. (wikipedia.org)
  • For example, with the exception of certain flies, most insects use the xanthophyll derived R-isomer of 3-hydroxyretinal for visual activities, which means that β-cryptoxanthin and other xanthophylls (such as lutein and zeaxanthin) may function as forms of visual "vitamin A" for them, while carotenes (such as beta carotene) do not. (wikipedia.org)
  • The overall xanthophyll content in the petals of flowers has been determined spectrophotometrically, while the composition of lutein diesters in each Tagetes species as well as the composition of anthocyanins in the flowers with claret spots have been studied by reverse phase HPLC. (springer.com)
  • It is shown that more than 90% of xanthophylls in flowers are retained upon drying and the content of lutein diesters in the dry material can exceed 15 mg/g. (springer.com)
  • Marigold Extract is a dry stabilized source of natural xanthophylls (Lutein) extracted from Marigold flowers (Tagetes erecta). (tktrading1.com)
  • Lutein is synthesized only by plants and like other xanthophylls is found in high quantities in green leafy vegetables such as spinach, kale and yellow carrots. (disabled-world.com)
  • In higher plants, there are three carotenoid pigments that are active in the xanthophyll cycle: violaxanthin, antheraxanthin, and zeaxanthin. (wikipedia.org)
  • The overlap of xanthophyll pigments-related photoprotective NPQ with several other mechanisms involved in the cell response (Photosystem II photoinactivation, changes in pigments composition, and detoxification by antioxidants) to energy unbalance is further discussed. (ifremer.fr)
  • Synthesis of xanthophyll cycle pigments occurred in both species, and was faster for D. tertiolecta during PAR + UV than during PAR exposure. (rug.nl)
  • Chlorophyll, the green color of leaves breaks down and exposes yellow and orange pigments, called carotene and xanthophyll. (ehow.com)
  • The product is a mixture of natural xanthophyll carotenoid pigments and Bioperine, the company's patented nutrient bioavailability enhancer. (nutraingredients.com)
  • Leaves that change from green to yellow or orange are simply reverting back to the other pigments (xanthophyll and carotenes) already present. (tpwmagazine.com)
  • In diatoms and dinoflagellates, the xanthophyll cycle consists of the pigment diadinoxanthin, which is transformed into diatoxanthin (diatoms) or dinoxanthin (dinoflagellates) under high-light conditions. (wikipedia.org)
  • In addition, pigment composition, xanthophyll de-epoxidation state and carbon assimilation were assessed during the fluctuating irradiance cycles. (rug.nl)
  • macular cyst): Tangential vitreous traction results in the elevation of the fovea marked by increased clinical prominence of xanthophyll pigment. (medscape.com)
  • Stage 1b: As the foveal retina elevates to the level of the perifoveal, the yellow dot of xanthophyll pigment changes to a donut shaped yellow ring. (medscape.com)
  • It contains protein, fatty acids, vitamins and minerals as well as antioxidants such as beta-carotene, xanthophylls and C-phycocyanins. (smithsfoodanddrug.com)
  • Their content of oxygen causes xanthophylls to be more polar (in molecular structure) than carotenes, and causes their separation from carotenes in many types of chromatography. (wikipedia.org)
  • Carotenes are usually more orange in color than xanthophylls. (wikipedia.org)
  • Xanthophylls and Carotenes. (vitacart.com)
  • Marigold Extract (Xanthophyll 2%), Wholesale Marigold Extract (Xanthophyll 2%) អ្នកផ្គត់ផ្គង់ និងអ្នកផលិត -TK Trading Co., Ltd. (tktrading1.com)
  • Short-term ultraviolet (UV) radiation (280-400 nm) effects on xanthophyll cycle activity and photosynthesis were assessed during fluctuating irradiance (60- and 10-min cycles - saturating irradiance to near-zero irradiance) for the marine algae Thalassiosira (Bacillariophyceae) and Dunaliella tertiolecta (Chlorophyceae). (rug.nl)
  • It is for this reason that we conducted a parallel study to unravel the possible effect on cardiometabolic parameters of the ingestion of anthocyanins, xanthophylls, or both groups of bioactives together in postmenopausal women. (ucm.es)
  • Postmenopausal women could benefit from an increase in anthocyanins and xanthophylls intake, through the consumption of fruits and vegetables rich in these two types of compounds. (ucm.es)
  • Xanthophylls present their oxygen either as hydroxyl groups and/or as hydrogen atoms substituted by oxygen atoms when acting as a bridge to form epoxides. (wikipedia.org)
  • meso -Zeaxanthin ( 3R,3´S-Zeaxanthin ) is a xanthophyll carotenoid , as it contains oxygen and hydrocarbons, and is one of the three stereoisomers of zeaxanthin . (wikipedia.org)
  • The accumulation of xanthophylls in flowers of marigold ( Tagetes ) species cultivated under conditions of the Belgorod region has been studied. (springer.com)
  • The xanthophyll cycle involves the enzymatic removal of epoxy groups from xanthophylls (e.g. violaxanthin, antheraxanthin, diadinoxanthin) to create so-called de-epoxidised xanthophylls (e.g. diatoxanthin, zeaxanthin). (wikipedia.org)
  • Astaxanthin (AST) is a xanthophyll carotenoid that has recently been demonstrated to have anti-inflammatory effects and to regulate the expression of inflammatory cytokines. (positivehealth.com)
  • In species other than mammals, certain xanthophylls may be converted to hydroxylated retinal-analogues that function directly in vision. (wikipedia.org)
  • It is established that the total content of xanthophylls and their composition are close to the published data for analogous species growing in other regions of the world. (springer.com)
  • This coincided with maximal xanthophyll de-epoxidation that developed during the course of the day for both species. (rug.nl)
  • Carbon incorporation and on most occasions PSII quantum yield in the light were lower during UV exposure for both species, regardless of xanthophyll de-epoxidation state. (rug.nl)
  • The latter compound is the only known xanthophyll to contain a beta-ionone ring, and thus β-cryptoxanthin is the only xanthophyll that is known to possess pro-vitamin A activity for mammals. (wikipedia.org)
  • At M2, total xanthophylls were significantly increased only in group 1 and decreased in group 2. (karger.com)
  • The xanthophyll group is the most complex carotenoid group in terms of number of compounds and variation in their structure. (shimadzu.com)
  • The naturally complex availability of xanthophylls is increased by the formation of these carotenoid esters. (shimadzu.com)
  • A rise in the systemic level of total xanthophylls was observed at M1 for both groups. (karger.com)
  • Dynamic xanthophyll cycle (XC) related non-photochemical quenching (NPQd, also called qE) is present in most phototrophs. (ifremer.fr)
  • Maximal xanthophyll de-epoxidation and NPQ at noon was lower under photosynthetically active radiation (PAR) + UV than under PAR exposure for T weissflogii during the 10-min cycle, whereas this was not found for the 60-min cycle and in D. tertiolecta. (rug.nl)
  • The xanthophylls found in the bodies of animals including humans, and in dietary animal products, are ultimately derived from plant sources in the diet. (wikipedia.org)
  • Again, both these specific xanthophylls require a source in the human diet to be present in the human eye. (wikipedia.org)
  • It contains different xanthophylls level with approx. (tktrading1.com)
  • The recommended dose is 100-125 milligrams of ZeaLutein per day, which corresponds to 6-8 milligrams of active xanthophylls. (nutraingredients.com)
  • Along with green chlorophyll pigments, xanthophylls help plants absorb light energy and regulate heat. (birchandfog.biz)
  • If a cannabis plant is stressed or deficient in key nutrients, chlorophyll can break down, revealing the yellow xanthophylls in a condition known as chlorosis or yellowing leaves. (birchandfog.biz)
  • However, xanthophylls become visible in leaves when a plant lacks nutrients, especially nitrogen, causing chlorophyll levels to drop. (birchandfog.biz)
  • This was associated with decreased levels of total chlorophyll and increased levels of xanthophyll-cycle pigments. (edu.au)
  • Chlorophyll, xanthophylls, and carotenes are present in leaves all along, and are important in harvesting sunlight for energy production and protecting the leaves from some of the damaging impacts of sunlight. (newildernesstrust.org)
  • this masks the other pigments, Chlorophyll a and c (no chlorophyll b), beta-carotene and other xanthophylls. (vliz.be)
  • In addition to chlorophyll, leaves also contain yellow and orange pigments, such as xanthophyll and carotene. (umaine.edu)
  • No. The yellow color of egg yolks comes from plant pigments called xanthophylls that the hen gets from her food. (americastestkitchen.com)
  • Hens fed a diet rich in yellow/orange plant pigments called xanthophylls tend to lay darker colored eggs. (colorwithleo.com)
  • These are chlorophyll's shy cousins, the yellow pigment xanthophyll and the red-orange carotene. (english-dictionary.help)
  • Oxidation products of carotene are called xanthophylls. (fao.org)
  • Research additional functions of -carotene monooxygenases for regulation of xanthophylls levels in the human macula.Mentor junior staff in the laboratory. (nih.gov)
  • It is a plastid, containing pigments such as xanthophyll (yellow in color) and carotene (orangish-red in color). (syvum.com)
  • Fucoxanthin xanthophyll is created using fucoxanthin kelp extract. (prdealz.com)
  • Feed Additives Mixture Natural Xanthophyll Marigold Extract Nature Yellow-Supplement of Xanthophylls extracted from marigolds, raw materials for animal husbandry and aquaculture, In accordance with Decision No. 563 / QD-CN-TCN. (vietnamtrades.com)
  • Example: Xanthophyll from the marigold flower is a potent antioxidant. (greenopolis.com)
  • Common feed ingredients that increase xanthophyll intake include corn, alfalfa, and marigold petals. (colorwithleo.com)
  • We will conduct animal studies to investigate how one dietary phytochemical, xanthophyll beta-cryptoxanthin (BCX), inhibits metabolic syndrome, nonalcoholic fatty liver disease and liver cancer (hepatocellular carcinoma) development in the liver. (usda.gov)
  • Xanthophylls are carotenoid pigments from plants, algae and fish that possess powerful antioxidant properties. (paulaschoice.co.uk)
  • To examine the association between xanthophyll intake and prevalent early age-related macular degeneration (AMD) using data from the Atherosclerosis Risk in Communities Study (n = 10,295). (nih.gov)
  • Xanthophylls are yellow pigments naturally present in the leaves of cannabis and other plants. (birchandfog.biz)
  • Leader Yellow: Xanthophyll supplement material in feed. (vietnamtrades.com)
  • This allows carotenoid (orange) and xanthophyll (yellow) pigments in the leaves to emerge. (yahoo.com)
  • Xanthophylls are responsible for the more subdued yellow hues that we see in leaves during the fall. (vilesarboretum.org)
  • In this context, xanthophylls can protect other molecules from oxidative stress by turning off singlet oxygen damage through various mechanisms. (uvigo.es)
  • Xanthophylls are also popular in oral supplement form due to their proven antioxidant effects. (paulaschoice.co.uk)
  • 13. Metabolic engineering of xanthophyll content in tomato fruits. (nih.gov)
  • Based on clinical studies, this review shows the available information concerning the bioactivity and biological effects of the main xanthophylls present in algae. (uvigo.es)
  • However, the extraction and purification processes of xanthophylls from algae need to be standardized to facilitate their commercialization. (uvigo.es)
  • Few Sample Shipment Records of Xanthophyll Supplement imports in vietnam are given above. (vietnamtrades.com)
  • Seeing xanthophyll pigments emerge in cannabis leaves alerts growers to a potential problem. (birchandfog.biz)
  • Xanthophyll intake was assessed at visit 1 (1987-1989) using food frequency questionnaires. (nih.gov)
  • Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for AMD by quintiles of xanthophyll intake, adjusted for age, sex, race, field center, and pack-years of smoking. (nih.gov)
  • We will investigate the protective effects of xanthophyll BCX against HRCD-promoted HCC in both young and old mice respectively. (usda.gov)
  • Xanthophylls present their oxygen either as hydroxyl groups and/or as hydrogen atoms substituted by oxygen atoms when acting as a bridge to form epoxides. (wikipedia.org)
  • Again, both these specific xanthophylls require a source in the human diet to be present in the human eye. (wikipedia.org)
  • 4. Green Leafy VegetablesGreen leafy vegetables such as spinach and kale contain xanthophylls. (lebaccanti.com)
  • Due to their ability to offset environmental stressors, xanthophylls are welcome additions to skin care formulas. (paulaschoice.co.uk)
  • The xanthophylls found in the bodies of animals including humans, and in dietary animal products, are ultimately derived from plant sources in the diet. (wikipedia.org)