Essay On Carotenoids

Earth is a planet dominated by plants. These plants are essential to all other life. For example, the oxygen we breathe, the nutrients we consume, the fuels we burn and many of the most important materials we use were produced by plants. It is estimated that there are about 250,000 - 500,000 species of plants on the earth, and nearly 10% of these are used as food and medicine by humans and other living things, but thousands of compounds have been extracted from these plants which possess various of properties that have proposed and significant effects on, and benefits for both plants and humans. These compounds are known as phytochemicals, phyto means "plant" in Greek, which are non-nutritive, naturally occurring biochemicals. These chemicals are produced by plants to protect them against environmental hazard and stress such as water changes and microorganisms, including viruses,

Moreover, among the 50 provitamin, there are 3 carotenoids that are considered as the most significant precursors of vitamin A in humans which are b-cryptoxanthin, a-carotene and b-carotene that are converted and metabolized to vitamin A in the body. The importance of these provitamin carotenoids is that they serve as a source of vitamin A which is needed for normal growth and development, immune system function and vision.

Carotenoids as antioxidant Carotenoids have the ability to function as antioxidants and promote oxidative stress resistance. In plants, antioxidant activity of carotenoids is based on their singlet oxygen quenching properties. In the human, carotenoids are part of antioxidant defense system that work in two ways either by singlet oxygen quenching properties as in plants or through scavenging oxidizing free radicals via giving the free radical its missing electron instead of taking it from other macromolecules.