## 2 Materials and Methods
### Quality Parameters
#### 2.3.2 Phytochemical Properties Measurement  
Extract Preparation  
[PERSON] et al. [41] procedure was used to prepare the extract. The dried sample was ground and passed through a sieve (40-mesh). A total of 2 g of sample powder was added to 4 mL of 50% ethanol (_v/v_). The mixture was mixed to homogenize it and was then was kept at room temperature. After 1 h, the supernatant was transferred to a volumetric flask. A total of 4 mL of 70% acetone was added to the rest of the extract and homogenized using a mixer and kept at room temperature for 1 h. the obtained supernatant was transferred to the same flask containing the first supernatant and the solution volume was brought to 100 mL by distilled water and mixed well. Extraction was performed in triplicate for each treatment. Determination of Antioxidant Activity by DPPH Method  
To assess the antioxidant potential by DPPH free radical scavenging, changes in (DPHH) absorbance are examined. 1, 1-diphenyl-2-picrylhydrazyl (DPPH) is a stable free radical that can accept an electron or hydrogen molecule and become a neutral and stable molecule. DPPH has a strong absorption at a wavelength of 517 nm due to its odd electron; at this stage, the methanolic solution of DPPH is a deep purple color. In the presence of antioxidants, the odd electron can become an electron pair. Regarding the number of electrons received, absorption is reduced. At this stage, the color of the solution turns yellow/colorless. Using this absorption change, the ability of different compounds for free radical scavenging can be measured. The amount of change in the absorption of each sample depends on the ability of the radical adsorbent. To determine the antioxidant activity, 1 mL of DPPH methanol solution (1 mM), was mixed with 3 mL of sample extract. The mixtures were maintained in a dark place at room temperature; after 30 min, the absorbance was read at 517 nm. The experiment was repeated three times for each sample solution. Antioxidant activity was calculated as the inhibition percentage was calculated by  
\[\%\text{Inhibition}=1-\frac{\text{A}_{\text{sample}}}{\text{A}_{\text{ control}}} \tag{2}\]  
where A\({}_{\text{sample}}\) is the absorbance of DPPH with the extracts and A\({}_{\text{control}}\) is the absorbance of DPPH without the extracts. Measurement of Total Phenolic Content (TPC)  
The total phenol content (TPC) was determined using Folin-Ciocalteu assay by a UV/Vis spectrophotometer. A total of 10 mg m/L of the extract was mixed with 1 mL of Folin-Ciocalteu's reagent, and after 3 min, 0.8 mL of Na\({}_{2}\)CO\({}_{3}\) (2%) was added, and then the volume was increased to 10 mL with water/methanol (4:6). After 30 min, the absorbance of the samples was measured at 740 nm. Tannic acid (0-800 mg/L) was used as the standard calibration curve, the TPC was reported to mg of tannic acid equivalent per gram of extract. The experiments were repeated in triplicate and their mean was reported. Measurement Anthocyanin Content (A)  
For determination of anthocyanins content (A), 0.1 g of the sample was soaked in 10 mL of acidified methanol (methanol/HCl = 99:1, _v/v_). The extract was maintained for 24 h in the dark at 25 \({}^{\circ}\)C. The extract was then centrifuged at 5000 rpm for 5 min. Absorption of the supernatant was measured at 550 nm. Evaluation of Total Flavonoid Content (TFC)  
The Dowd method, modified by [PERSON] et al. [42], was used to measure the total amount of flavonoids. Briefly, in this method, 5 mL of 2% AlCl\({}_{3}\) in methanol was mixed with the same volume of aqueous extract. After 10 min, the absorbance of the extract solution and the blank solution (containing 5 mL of the extract with 5 mL of ethanol without AlCl\({}_{3}\) was read at 415 nm. Then, the total flavonoid content was determined using the quercetin standard curve (0-100 mgL) and was expressed as mg of quercetin equivalent per gram of dry mass of petals. Losses of phytochemical properties of _E.