Friday, December 31, 2010

Understanding amino acid metabolism

Chemical processes by which amino acids are either synthesized or are broken down and are used for energy in the body.
Amino acid synthesis is important because approximately half of the different amino acids used as PROTEIN building blocks can be made from CARBOHYDRATES.
Amino acids such as ALANINE, GLUTAMIC ACID, and GLUTAMINE made by the brain and MUSCLE help transport NITROGEN waste products via the bloodstream to the LIVER for disposal. When amino acids are degraded, the first step (transamination) releases nitrogen with the help of VITAMIN B6. The final nitrogen-containing waste product is UREA. The second step of amino acid degradation requires the oxidation of the carbon atoms of amino acids to produce ATP, the energy currency of cells. The waste product is CARBON DIOXIDE. An alternative route permits the liver to convert most amino acids to blood sugar (GLUCOSE) when the diet does not provide adequate carbohydrates that can be digested to glucose to fuel the brain. This process is called GLUCONEOGENESIS. HEME (the pigment of red blood cells), neurotransmitters (brain chemicals that carry nerve impulses), purines (building blocks of RNA and DNA), and HORMONES represent important amino acid derivatives.

What is Amine?

A very large family of basic organic compounds that contain nitrogen. Amines become positively charged ions (cations) in the blood.
Physiologically important amines include the hormones EPINEPHRINE (adrenaline) and norepinephrine, and neurotransmitters such as ACETYLCHOLINE and SEROTONIN, chemicals released by activated nerve cells. CHOLINE serves as a raw material for both acetylcholine and LECITHIN, a common LIPID of cell membranes. All AMINO ACIDS used to build PROTEINS have properties of amines. Tyramine found in fermented foods is an amine that can cause headache and food sensitivities. A variety of amines in food can react with the food additive nitrite to produce cancer-causing substances (nitrosoamines).

Nutritional Value of Amaranth (Amaranthus cruentus; grain amaranth)

A nutritious alternative to WHEAT. The tiny spherical seeds are the size of poppy seeds. Originally grown in Mexico as a staple food of the Aztecs, it was eaten in rituals of Native Americans until the Spanish conquest of Mexico, when its cultivation was outlawed.
Amaranth is now cultivated in the United States, and its excellent nutritional qualities account for its present popularity. Amaranth possesses a higher PROTEIN content than most CEREAL GRAINS; the nutritional value of amaranth protein approaches that of MILK. Its protein contains a high percentage of the essential AMINO ACID lysine, which is low in other grain proteins like wheat. Amaranth does not contain typical wheat ALLERGENS, nor does it contain GLUTEN; therefore, people allergic to wheat can often eat amaranth because it belongs to an unrelated plant family. Amaranth is available in health food stores as a whole grain, a FLOUR, and as CRACKERS and breakfast cereals. Amaranth flour has a nutty flavor and can be used to supplement wheat flour. Popped amaranth seed is mixed with honey to make a Mexican confection known as alegria. Amaranth species have also been cultivated in Asia as a source of greens (een choi in China, hiyu in Japan, and CHAULAI in India). One hundred grams of amaranth provides protein, 15 g; carbohydrate, 66 g; fiber, 4.5 g; fat, 5.7 g; and fat, 4.5 g.