## 1 Introduction  
Reactive oxygen species (ROS) is a commonly used term in biology to describe unstable and highly reactive oxygen-containing chemicals in mammalian cells, including hydrogen peroxide, hydroxyl radicals, superoxide, peroxynitrite, lipid hydroperoxide, singlet oxygen, hypochlorous acid, ozone, alkoxyl radical, and peroxyl radical [1; 2; 3]. These molecules are either physiological by-products of the aerobic mitochondrial metabolism or generated as immune responses to pathogens, xenobiotics, and cytokines [4; 5]. However, ROS production is necessary for cellular signaling, overproduction of ROS could lead to various tissue and organ failures through damaging lipids, proteins, carbohydrates, and DNA. The diseases linked to ROS include neurodegenerative, digestive, cancer, respiratory, endocrine, cardiovascular diseases, and age-accelerating the processes [6; 7; 8; 9]. The sources of ROS production are either exogenous or endogenous. The exogenous triggers to produce ROS could be ionizing radiation, tobacco, alcoholic drinks, pollutants, ultraviolet (UV) radiation, food, and medications. On the other hand, intracellular enzymes are the main sources of endogenous ROS production [10]. Antioxidants are stable molecules that can neutralize free radical molecules in vivo by donating electrons and have the capability to prevent or reduce cell and tissue damage [11]. The sources of these free radical-scavenging molecules are either endogenous or exogenous. Endogenous antioxidants can be classified into enzymatic and non-enzymatic antioxidants when they are produced by normal cell metabolism. In contrast, exogenous antioxidants are compounds that cannot be produced in the body; therefore, they must be administered either as nutrients or as dietary supplements [12; 13]. The human body's defense cells have an efficient capacity to neutralize overproduced ROS and minimize the harmful effects induced by oxidative stress [14; 15]. Nevertheless, the efficiency of this system could be compromised by several factors, such as diet, age, lifestyle, and diseases. Therefore, antioxidants could be essential to keep the ROS/defense system balance in equilibrium [9; 16]. Currently, scientific communities have focused on the nutrient antioxidants due to the side effects connected to the consumption of dietary supplements [17]. The plant sources of antioxidant compounds are herbs, fruits, food products, seeds, spices, and vegetables [18]. Plants contain various hydrophilic and lipophilic phytochemicals to use as antioxidants [19]. Hydrophilic antioxidant molecules include anthocyanins, phenolics, and ascorbic acid, while lipophilic bioactive antioxidant compounds include chlorophylls, tocopherols, carotenoids, and unsaturated fatty acids (UFAs), which are mono and polyunsaturated fatty acids (MUFAs and PUFAs) [20; 21; 22]. Plant oils contain three types of fatty acids: saturated fatty acids (SFAs), MUFAs, and PUFAs. MUFAs are fatty acids with a chain containing one C-C double bond due to a two-hydrogen atom deficit [23]. They have health benefits because they could reduce insulin resistance, inflammation, oxidative stress, and dermatoheliosis [24]. Likewise, PUFAs are known as good and essential fats because they have significant health benefits through the regulation of cellular activities and antioxidant properties [25; 26]. PUFAs are amphipatic organic compounds with long hydrocarbon chains, contain two or more carbon-carbon double bond and end with carboxylic acid (Figure 1). They are mainly omega-3 and omega-6 fatty acids, which cannot be produced endogenously. The difference between both omega 3 and 6 is referred to the last carbon-carbon double bond location [27]. The antioxidant activity of MUFAs and PUFAs could be through the inhibition of inflammatory responses, prevention of platelet aggregation, and the protection of vascular endothelial cells, cardiac cells, and neurons from damage [28; 29; 30; 31].