## 4 Discussion
The aim of this study was to investigate the extent to which the use of oral antioxidants prior to ionizing radiation exposure could counteract oxidative stress. Angelica archangelica root water extract has wide medical uses as an antioxidant because of its main active ingredients, which include \(\alpha\)-pinene (15.7-20.8%), \(\delta\)-3-carene (15.4-16.9%), limonene (8.0-9.2%), \(\beta\)-phellandrene (13.5-15.4%), \(\alpha\)-phellandrene (8.0-9.1%), and \(p\)-cymene (6.8-10.6%) [24]. The antioxidant activity of \(A\). archangelica essentially dependents on the mode of extraction, which controls variable radical scavenging and the level of peroxidation activities. Regarding different higher modes of chemical extraction, \(A\). archangelica contains 1,1-diphenyl-2-picrylhydrazil (DPPPH), 2,2-azino-bis (3 ethylbenzodiazep-6-sulfonic acid (ABTS), and \(\beta\)-carotene, and these active ingredients are believed to increase the antioxidant activity of extracts. G. biloba contains three major chemical active ingredients: ginkgolides, bilobalides, and flavonoids. Such compounds are found in extracts such as flavanol, flavone glycosides, ascorbic acid, catechin, iron-based superoxide, protocatechuic acid, sterols, and vanillic acid [23]. G. biloba has a long history of use in traditional medicine for the protection of neurons from damage due to oxidation, the prevention of tissue degeneration in dementia patients, improving blood flow and circulation throughout the body, and restoring prostacyclin and thromboxane A2, which improves vasoregulation. Previous chemical analysis of the antioxidants in \(A\). archangelica and G. biloba has demonstrated that both of these plants have antioxidant activities. A study was carried out to assess their ability to inhibit oxidative stress as a protective treatment against injuries of the eye lens and confirmed that the use of both herbs before radiation exposure significantly controlled ROS [23]. In healthy blood, oxyhemoglobin should be the most abundant derivative and levels must be above 97% to ensure normal gas transportation. This derivative has high sensitivity to free radicals, as a tiny amount of ROS can alter its iron atom electrical properties and produce another form of hemoglobin, Met-Hb. In this study, different hemoglobin derivative concentrations were calculated and are shown in Table 1 and Figure 1. Rabbits that were exposed to radiation by means of Gallium-68 injections with no prior protective antioxidant treatment revealed a highly significant decrease in oxyhemoglobin concentrations, with a highly significant increase in the oxidized form of hemoglobin, methemoglobin. Exposure to ionizing radiation only and with no prior antioxidant treatment resulted in the excessive production of ROS, which played a role in an array of oxidation events that resulted in higher levels of oxidized hemoglobin derivative, i.e., methemoglobin, with a significant reduction in the levels of oxyhemoglobin (G1). This effect seemed to be controlled by the application of both antioxidants, \(A\). angelica and G. biloba, i.e., Groups 2 and 3, for seven days before exposure to radiation. Another method to determine whether both these antioxidants can play a role as protective treatments against cell oxidative stress is to study the activity level of natural body antioxidants. Hemoglobin molecules are continuously involved in oxidation reduction. The human bodyguards, SOD and GPX, play an essential role in maintaining normal functional derivatives such that hemoglobin is able to carry out its normal functions. The activity of these antioxidants is normally increased when blood is exposed to an oxidizing agent, such as ionized radiation, in order to restore the reduced form of molecules [24]. Therefore, an assessment of the activities of these antioxidants could show the existence of free radicals.