Free radicals is a compound in a free state, which has one or more unpaired electrons that are reactive (Halliwell & Gutteridge 2006). Molecules or atoms are trying to achieve steady state with another electron attractive way to form a new radical. This free radical reactions take place in sequence (cascade reaction) (Haliwell & Gutteridge 1999; Jakus 2002).
According to Halliwell (2006) and Nurmi (2008) there are several types of free radicals. In living systems the majority of free radicals derived from oxygen and its derivatives are known as ROS (Reactive Oxigen Species). ROS is a reactive atoms or molecules derived from oxygen (O2). All free radicals are included in the ROS but not all ROS are free radicals. The other type of free radicals derived from nitrogen, known RNS (Reactive Nitrogen Species), which is known RBS bromine (bromine reactive species) and chlorine are known RCS (reactive chlorine species).
ROS are free radicals such as superoksidase anion (* O2), hydroxyl radical (* OH), alkolsil radicals (RO *), radical peroksil (Roo *), lipid peroxidase (loo *) and non-radical is not H2O2, singlet oxygen (1O2), gipoklorus acid (HOCl) and aldehyde (Halliwell & Gutteridge 2001; Ziyatdhinova et al. 2006).
ROS in biological systems of the body can come from outside the body (exogenous) and internal (endogenous). Exogenous source of free radicals or ROS consists of pulutan, ozone, high concentrations of oxygen and hyperbaric oxygen due to non-ionizing and ionizing irradiation, chemicals, cigarette smoke, toxins, bacteria, pathogens and viruses (Halliwell & Gutteridge 2000; Ziyatdhinova et al. 2006) . Endogenous sources originating from 1) the process of respiration (Lehninger 1993), 2) enzyme xanthine oxidase; 3) On the synthesis of nitric oxide (Haliwell & Gutteridge, 1999; Ziyatdhinova et al. 2006); 4) Reduction of O2 to superoxide from phagocytosis. (Haliwell & Gutteridge 1999; Ziyatdhinova et a. 2006); 5) Fenton reaction and harber-Weiss (Haliwell & Gutteridge 1999); 6) Reaction eikosanoid metabolism; 6) platelet aggregation (Rise-evan et al. 1991; Haliwell & Gutteridge 1999; Nurmi 2008) and 7) apoptotic cells (Roitt & Delves, 2001; Haliwell & Gutteridge 1999).
ROS, RNS can be positive and negative. Its positive qualities play a role in the process of biological functions in a controlled amount (Batish et al. 2006). Negative nature of free radicals (ROS / RNS) can bind directly with membrane lipids, protein structure, enzyme RNA and DNA cross-links intramolekuler forming cells or between molecules that cause damage and decrease in cell biological functions.
In the body there is also a natural defense mechanism against the negative nature of free radicals by endogenous antioxidant enzyme beruapa mentralkan ROS so as not to give a negative nature. Antioxidants itself is a chemical substance in a low number to prevent the oxidation of cellular organelles to minimize cell damage caused by ROS / RNS or oxidative stress (Priyadarsini 2005). According to Train (2003) ankitioksidan is a group of components that can damage the ROS so as to protect or prevent oxidative damage to cells. According to Anon (2002) antioxidant is a chemical component that could delay or slow the rate of lipid oxidation.
According to Halliwell (2006) and Nurmi (2008) there are several types of free radicals. In living systems the majority of free radicals derived from oxygen and its derivatives are known as ROS (Reactive Oxigen Species). ROS is a reactive atoms or molecules derived from oxygen (O2). All free radicals are included in the ROS but not all ROS are free radicals. The other type of free radicals derived from nitrogen, known RNS (Reactive Nitrogen Species), which is known RBS bromine (bromine reactive species) and chlorine are known RCS (reactive chlorine species).
ROS are free radicals such as superoksidase anion (* O2), hydroxyl radical (* OH), alkolsil radicals (RO *), radical peroksil (Roo *), lipid peroxidase (loo *) and non-radical is not H2O2, singlet oxygen (1O2), gipoklorus acid (HOCl) and aldehyde (Halliwell & Gutteridge 2001; Ziyatdhinova et al. 2006).
ROS in biological systems of the body can come from outside the body (exogenous) and internal (endogenous). Exogenous source of free radicals or ROS consists of pulutan, ozone, high concentrations of oxygen and hyperbaric oxygen due to non-ionizing and ionizing irradiation, chemicals, cigarette smoke, toxins, bacteria, pathogens and viruses (Halliwell & Gutteridge 2000; Ziyatdhinova et al. 2006) . Endogenous sources originating from 1) the process of respiration (Lehninger 1993), 2) enzyme xanthine oxidase; 3) On the synthesis of nitric oxide (Haliwell & Gutteridge, 1999; Ziyatdhinova et al. 2006); 4) Reduction of O2 to superoxide from phagocytosis. (Haliwell & Gutteridge 1999; Ziyatdhinova et a. 2006); 5) Fenton reaction and harber-Weiss (Haliwell & Gutteridge 1999); 6) Reaction eikosanoid metabolism; 6) platelet aggregation (Rise-evan et al. 1991; Haliwell & Gutteridge 1999; Nurmi 2008) and 7) apoptotic cells (Roitt & Delves, 2001; Haliwell & Gutteridge 1999).
ROS, RNS can be positive and negative. Its positive qualities play a role in the process of biological functions in a controlled amount (Batish et al. 2006). Negative nature of free radicals (ROS / RNS) can bind directly with membrane lipids, protein structure, enzyme RNA and DNA cross-links intramolekuler forming cells or between molecules that cause damage and decrease in cell biological functions.
In the body there is also a natural defense mechanism against the negative nature of free radicals by endogenous antioxidant enzyme beruapa mentralkan ROS so as not to give a negative nature. Antioxidants itself is a chemical substance in a low number to prevent the oxidation of cellular organelles to minimize cell damage caused by ROS / RNS or oxidative stress (Priyadarsini 2005). According to Train (2003) ankitioksidan is a group of components that can damage the ROS so as to protect or prevent oxidative damage to cells. According to Anon (2002) antioxidant is a chemical component that could delay or slow the rate of lipid oxidation.
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