Science Glossary

Terms - (Important Words to know)

Glutathione - is a tripeptide. It contains an unusual peptide linkage between the amine group of cysteine and the carboxyl group of the glutamate side chain. Glutathione, an antioxidant, protects cells from toxins such as free radicals.
Superoxide Dismutase - (SOD) are a class of enzymes that catalyze the dismutation of superoxide into oxygen and hydrogen peroxide. As such, they are an important antioxidant defense in nearly all cells exposed to oxygen. One of the exceedingly rare exceptions is Lactobacillus plantarum and related lactobacilli, which use a different mechanism.
Tbars - The sensitivity of measuring Thiobarbituric Acid Reactive Substances (TBARS) has made this assay the method of choice for screening and monitoring lipid peroxidation, a major indicator of oxidative stress.
Phytochemicals - are plant-derived chemical compounds such as diindolylmethane, some of which under scientific research for their potential health-promoting properties. Phytochemicals (or "phytonutrients") are non-essential nutrients, but many have been scientifically confirmed as being beneficial to human health.
Catalase - (CAT) is a common enzyme found in nearly all living organisms which are exposed to oxygen, where it functions to catalyze the decomposition of hydrogen peroxide to water and oxygen.[1] Catalase has one of the highest turnover numbers of all enzymes; one molecule of catalase can convert millions of molecules of hydrogen peroxide to water and oxygen per second.
Antioxident Enzymes - Form the first line of defense against free radicals in organisms. Their regulation depends mainly on the oxidant status of the cell, given that oxidants are their principal modulators. However, other factors have been reported to increase antioxidant enzyme activity and/or gene expression.
Oxidative Stress - is caused by an imbalance between the production of reactive oxygen and a biological system's ability to readily detoxify the reactive intermediates or easily repair the resulting damage. All forms of life maintain a reducing environment within their cells. This reducing environment is preserved by enzymes that maintain the reduced state through a constant input of metabolic energy. Disturbances in this normal redox state can cause toxic effects through the production of peroxides and free radicals that damage all components of the cell, including proteins, lipids, and DNA.
Free Radicals - The free-radical theory of aging states that organisms age because cells accumulate free radical damage over time. A free radical is any atom or molecule that has a single unpaired electron in an outer shell. While a few free radicals such as melanin are not chemically reactive, most biologically-relevant free radicals are highly reactive. For most biological structures, free radical damage is closely associated with oxidative damage. Antioxidants are reducing agents, and limit oxidative damage to biological structures by passivating free radicals.

Non-Essential Nutrients - Nutrients can be divided into two groups -- nonessential and essential. The distinction between the two depends on whether we need to obtain them from food or not. For nonessential nutrients, such as cholesterol, we don't have to get them from food, because our bodies can produce them. For essential nutrients, such as fats, food is either the major or the only source for us to attain them. There are over 40 different types of essential nutrients, and scientists categorized them into six groups -- carbohydrates, proteins, fats, vitamins, minerals, and water.