Tuesday, April 12, 2011

Common antioxidants (scavengers)

1. Bilirubin
Bilirubin is a prosthetic group which helps to break down molecules into smaller units in releasing energy, excreted in bile and urine. It is a cellular antioxidant, by reverting to biliverdin, a green tetrapyrrolic bile pigment, once again when oxidized that inhibits the effects of mutagens.

2. Carotenoids
Carotenoids are organic pigments, occurring in the chloroplasts and chromoplasts of plants and some other photosynthetic organisms like algae, some bacteria.
a. Beta-carotene
Beta-Carotene, an organic compound and classified as a terpenoid, a strongly-coloured red-orange pigment in plants and fruits.
a.1. It is not toxic and stored in liver for the production of vitamin A that inhibits cancer cell in experiment. Beta-carotene also neutralize singlet oxygen before giving rise of free radicals which can damage of DNA, leading to improper cell DNA replication, causing cancers.
a.2. Cell communication
Researcher found that beta-carotene enhances the communication between cell can reduce the risk of cancer by making cells division more reliable.
a.3. Immune system
Beta-carotene promotes the immune system in identifying the foreign invasion such as virus and bacteria by increasing the quality of MHC2 protein in maintaining optimal function of white cells.
a.4. Polyunsaturated fat
Researchers found that beta-carotene also inhibits the oxidation of polyunsaturated fat and lipoprotein in the blood that reduce the risk of plaques build up onto the arterial walls, causing heart diseases and stroke.
a.5. There are more benefits of beta-carotene.

b. Alpha-carotene
Alpha-carotene, one of the most abundant carotenoids in the North American diet, is a form of carotene with a β-ring at one end and an ε-ring at the other. It is the second most common form of carotene which not only protects cells from the damaging effects of free radicals and enhances the immune system in fighting against bacteria and virus invasion, but also stimulates the communication between cells thus preventing irregular cell growth cause of cancers.

c. Beta-cryptoxanthin
Chemically Beta-cryptoxanthin is a xanthophyll which protects our cells from oxidation and provides a source of vitamin A and lowers the risk of inflammatory polyarthritis by enhancing the immune system functioning

d. Lutein
Lutein is one of the most popular North American carotenoids. It is found in greens like kale and spinach as well as the yolk of eggs. Lutein is also found in the human eye. Getting enough lutein in your diet may help to fight off age related macular degeneration, an eye condition. Research has shown that people who do not have enough lutein in their diet will not have enough lutein present in the macular part of the eye. This is what likely leads to age related macular degeneration that can result in blindness.

e. Zeaxanthin
Zeaxanthin, a most common carotenoid alcohols found in nature, is one of the two primary xanthophyll carotenoids contained within the retina of the eye. Intake of foods providing zeaxanthin with lower incidence of age-related macular degeneration as a result of its function of reducing the risk oxidative stress.

g. Lycopene
Lycopene is a red carotene of the carotenoid group that can be found in tomatoes, watermelons, and grapefruits. This powerful antioxidant is believed to be a powerful fighter of prostate cancer, breast cancer and liver diseases. Lycopene has many anti-aging capabilities as well as one of the most powerful antioxidants in the carotenoid group.

3. Flavonoids
Flavonoids also known as Vitamin P and citrin are a yellow pigments having a structure similar to that of flavones occurred in varies plants. it has been in human history for over thousands of years and discovered by A. S. Szent-Gyorgi in 1930. As he used vitamin C and flavonoids to heal the breakage of capillaries, which caused swelling and obstruction of blood flow. Most plants have more than one group or type act as predominate.
Flavonoids process a property as antioxidants. it helps to neutralize many of reactive oxygen species (ROS), including singlet oxygen, hydroxyl and superoxide radicals.
Although nitric oxide is considered a free radical produced by immune system to destroy bacteria and cancerous cells, but when it is over produced, it causes the production peroxynitrite which may attack protein, lipid and DNA, Flavonoids inhibit NO production of peroxynitrite due to reduction of enzyme expression.

a. Quercetin
Quercetin is a plant-derived flavonoid found in fruits, vegetables, leaves and grains and studies show that quercetin may have anti-inflammatory and antioxidant properties as a antioxidant, quercetin scavenges free radicals, which damage cell membranes, cause mutation of cells with tampering DNA.

b. Rutin
Rutin is a citrus flavonoid glycoside found in buckwheat and glycoside of the flavonoid quercetin. It inhibits platelet aggregation, decreases the capillary permeability, makes blood thinner and improves circulation. As an antioxidant, it can reduce the cytotoxicity of oxidized LDL cholesterol caused by free radical that lowers the risk of heart diseases.

c. Catechin
Catechin is a natural phenol antioxidant plant and natural anti-bacterial substance. Study showed catechin as good free radical scavenging power inhibits ROS production, thus it can be useful to the development of alimentary strategies to prevent OTA-induced cytotoxicity in human.

d. Etc.

4. Uric acids
Uric acids may have a potential therapeutic role as an antioxidant because of its function of inducing oxidative stress, either through creating reactive oxygen species or inhibiting antioxidant systems.
High uric acid can cause arthritis, cardiovascular disease, diabetes, Metabolic syndrome, kidney stones, etc.

5. Thiols (R-SH)
Chemically, thiol, a organosulfur compound have strong odors resembling that of garlic. They are used as odourants to assist in the detection of natural gas. It presents in the the amino acid cysteine which plays an important in functioning of enzyme regulation, control of gene expression, protein trafficking and receptor signalling. Thiols as sulfur residue, has reversal oxidation effects in cell controlling due to its interaction with GSSG, resulting in forming of intramolescular protein disulphide and GSH.

6. Coenzyme Q10
Coenzyme Q10 is discovered by Dr. Karl Folfers in 1957, beside promotes the chemical reaction, often by speeding it up or allowing it to proceed under less stringent conditions, it also enhances energy production by promoting the process of the production of ATP then serving as fuel for the cells and acts an antioxidant to prevent the generation of free radicals during this process.

7. Vitamin A, C, E. D.
a. Vitamin A
Vitamin A occurs in the form retinol and is best known for its function in maintaining the health of cell membrane, hair, skin, bone, teeth and eyes. It also plays an important role as an antioxidant as it scavenges free radicals in the lining of the mouth and lungs; prevents its depletion in fighting the increased free radicals activity by radiation; boosts immune system in controlling of free radicals; prevents oxidation of LDL and enhances the productions of insulin pancreas.

b. Vitamin C
Vitamin C beside plays an important role in formation and maintenance of body tissues, it as an antioxidant and water soluble vitamin, vitamin C can be easily carry in blood, operate in much of the part of body. By restoring vitamin E, it helps to fight against forming of free radicals. By enhancing the immune system, it promotes against the microbial and viral and irregular cell growth causes of infection and inflammation.
Vitamin C also is a scavenger in inhibiting pollution cause of oxidation.

c. Vitamin E
Vitamin E is used to refer to a group of fat-soluble compounds that include both tocopherols and tocotrienols discovered by researchers Herbert Evans and Katherine Bishop. It beside is important in protecting muscle weakness, repair damage tissues, lower blood pressue and inducing blood clooting in healing wound, etc, it also is one of powerful antioxidant, by moving into the fatty medium to prevent lipid peroxidation, resulting in lessening the risk of chain reactions by curtailing them before they can starts.

d. Vitamin D
Reseacher found that vitamin D, a group of fat-soluble secosteroids is also a membrane antioxidant, with the ability to inhibit iron-dependent lipid peroxidation in liposomes compared to cholesterol.