Extraction and Characterization of Fucoidan Derived from _Sargassum__ilicifolium_ and Its Biomedical Potential with In Silico Molecular Docking  
[PERSON]  
1 Department of Botany, Periyar University, Salem 636 011, India 1  
[PERSON]  
2 Department of Food Science and Biotechnology, College of Life Sciences, Sejong University, Seoul 05006,  
alignates. Of these, fucoidans mostly contain fucose and sulfate groups [7, 8]. In particular, fucoidans are more physiologically active elements in terms of structural qualifications [9]. Fucose backbones are mostly found in brown seaweeds [10]. However, species, habitat, and collecting season significantly affect fucoidan composition. The molecular weight and extraction methods of fucoidan are inter-linked based on the functional groups [11]. The bioactivity of fucoidan is determined by its extraction process, content, and structure. Additionally, environmental changes affect both nutritional and non-nutritional molecules, including antioxidants [12]. However, no standard extraction technique for fucoidan has been reported so far [13]. Recently, fucoidan has been isolated from brown algae such as _Sargassum filipendula_[14], _Sargassum wigthiti_, _Turbinaria ornata_, and _Padina tetrastromatica_[15].  
Fucoidan is non-toxic with therapeutic potential for cancer, cardiovascular disease, atherosclerosis, inflammation, and aging [16]. In living organisms, antioxidants act as free radical scavengers, inhibiting ROS, lipid peroxidation, protein breakdown, and DNA damage [17, 18]. The brown algae extracts exert antioxidant activity in the presence of high phenolic chemicals [19]. Processed meals often contain artificial antioxidants that can be harmful to humans [20]. Several natural antioxidants have been shown to reduce hyperlipidemia [21]. Additionally, many aquatic macroalgae species have been reported to have natural antioxidant properties that may protect from free radicals and prevent the occurrence of cardiovascular disease and diabetes [22, 23].  
Fucoidan research using brown seaweeds has broken through over the last four decades, due to its potential diverse pharmacological and biological applications such as antiviral, antimicrobial, antifungal, antioxidant [24, 25], anticoagulant, anti-thrombotic, antidiabetic [26], anti-inflammatory activity [27] and anti-cancer [28]. The amount of biologically active compounds in algae varies depending on the geographical origins, reproductive phase (sterile versus fertile), environmental stressors, and the collecting season. So far, many cancer cells have been examined to determine the anticancer properties of fucoidan [29]. Fucoidan could significantly inhibit the development of cancer tumors and increase the overall survival rate of cancer patients [30]. Therefore, the present study aimed to identify the proteins that may act as chemotherapeutic drugs in hepatocellular carcinoma using molecular docking. The antioxidant capacity of the cell could maintain redox balance and decrease oxidative stress. Numerous enzymes, including cytochrome P450 (CP450), lipoxygenase (LO), myeloperoxidase (MP), NADPH oxidase (NO), and xanthine oxidase, could induce ROS generation during the metabolism of arachidonic acid (XO). Subsequently, ROS generation could reduce oxidative stress, and maintain redox equilibrium by inhibiting these enzymes [31]. Increased oxidative stress by ROS is associated with various diseases, including cancer. Fucoidan is a possible precautionary and therapeutic agent for cancer without any harmful effects on the liver [32]. Therefore, fucoidan is very promising as a natural anticancer agent. Herein, fucoidan was used as an antioxidant and cancer-preventing agent through computational and in vitro methods. The present study focuses on the extraction and purification of fucoidan from _S. illifolium_, and evaluation of its anticoagulant, antioxidant, and anticancer activity in human hepatoma (HepG2) cells under in vitro conditions.