Human is always exposed to a variety of prooxidant agents that can lead to damaged biological important molecules such as DNA, proteins and lipids in body cells [1, 2]. In order to protect oneself against cell deterioration from prooxidants, carotenoid rich foods are:
- Effective Quenchers of Singlet Oxygen
Carotenoids quench singlet oxygen molecule by transferring the energy to carotenoid molecule to form ground state oxygen so that singlet oxygen molecule induced oxidative stress will not be propagated. In fact, the efficacy of carotenoids for physical quenching is associated with the number of conjugated double bonds present in the molecule, with higher number of conjugated double bonds indicate stronger antioxidants and vice versa .
- Strong Scavengers of Reactive Oxygen Species (ROS)
Carotenoids also react with peroxyl radicals in lipid peroxidation process and protect cellular membranes and lipoproteins against oxidative damage. The antioxidant activity of carotenoids in deactivating peroxyl radicals depends on the formation of a stabilized carbon-centered radical so that lipid peroxidation could be minimized [4, 5].
Synergistic Antioxidant Activities
The antioxidant defense system of a living organism is a complex network and comprises several enzymatic and non-enzymatic antioxidants . The interactions among different antioxidants confer additional protection against oxidative stress . For example, mixture of carotenoids have shown better inhibition of formation of thiobarbituric acid-relative substances (TBARS) (ie: better antioxidant activity) when compared to single carotenoid compound .
As oxidative stress is one of the main contributors to pathogenic processes of many diseases, hence carotenoids are strongly believed to mitigate the risks of developing chronic diseases such as cardiovascular diseases, age-related degenerative diseases, bone health, skin health , metabolic health as well as eye-related disorders. One good example is palm mixed-carotene which consists of a myriad of carotenoid compounds, namely alpha-carotene, beta-carotene, gamma-carotene, lycopene and minute amount of other carotenoids. Hence, each carotenoid isomer in the natural mixed-carotene works synergistically to provide unique biological health benefits.
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