## 2 Materials and Methods
### Determination of the Chemical Composition of Preparations from Fenugreek and Sweet Basil Seeds
#### 2.2.5 Determination of the Antioxidant Properties of NSP Preparations  
Extraction of Acidified Methanol Extractable Polyphenols  
A 0.25 g sample was weighed into a centrifuge tube, and 10 mL of 80% MeOH acidified with 0.1% HCl was added. The samples were then shaken on a Vortex microshaker (10 s). Subsequently, the samples were placed in an ultrasonic bath for 30 min, after which the samples were shaken for 60 min. Then, the samples were placed in a freezer (\(-25\)\({}^{\circ}\)C) for 20 h; successively, the samples were shaken for 90 min and centrifuged (7000\(\times\)\(g\); 10 min). The supernatant was transferred to a 10 mL volumetric flask and made up to the mark with 80% MeOH acidified with 0.1% HCl.  
Determination of Acidified Methanol Extractable Polyphenol Content  
The polyphenol content was determined according to [PERSON] et al. [27]. A total of 0.1 mL of extract, 2 mL of distilled water, 0.2 mL of Folin-Ciocalteu reagent (1.9-2.0 mol/L) and 1 mL of 20% sodium carbonate solution were added to each cuvette. Then, the samples were mixed and left in a dark place for one hour. After this time, the absorbance of the sample was measured on a spectrophotometer at \(\lambda\) = 765 nm against distilled water. The content of phenolic compounds was expressed in mg of gallic acid in 1 g of sample.  
Determination of Acidified Methanol Extractable Flavonoids  
The flavonoid content was determined according to [PERSON] et al. [28]. A total of 0.2 mL of extract was measured into cuvettes, then 2.8 mL each of distilled water, 0.12 mL of 5% NaNO\({}_{2}\) and 0.12 mL of 10% AlCl\({}_{3}\) solution were added. The whole mixture was mixed and allowed to stand for 5 min. After 6 min, 0.8 mL of 1M NaOH was added and mixed. The absorbance of the sample was then measured on a spectrophotometer at \(\lambda\) = 510 nm against a blank (the blank sample was prepared in the same way as the main samples, but acidified 80% methanol was used instead of the acidified methanol extract of the sample). The content of flavonoids was expressed in mg of catechin in 1 g of sample.  
Determination of the Antioxidant Activity of Acidified Methanol Extractable Polyphenols by the 2,2-Azino-bis-3-ethylbenzothazoline-6-sulfonic Acid (ABTS) Method  
The antioxidant activity by ABTS was determined according to [PERSON] et al. [29]. To 0.03 mL of extract, 3 mL of ABTS solution was added. After 6 min, the absorbance of the sample was measured on a spectrophotometer at \(\lambda\) = 734 nm, against distilled water as a blank. Antioxidant activity by ABTS was expressed in \(\mu\)M Trolox per 1 g sample.  
Determination of the 2,2\({}^{\prime}\)-Diphenyl-1-picrylhydrazyl (DPPH) Radical Scavenging Power of Acidified Methanol Extractable Polyphenols  
The DPPH radical scavenging power was determined according to [PERSON] and [PERSON] [30]. To 0.2 mL of extract, 2 mL of DPPH solution was added (in order to enhance the sensitivity of the assay, DPPH was diluted with ethanol in a ratio of 1:3), and after 10 min, the absorbance of the prepared sample was measured on a spectrophotometer at \(\lambda\) = 517 nm against ethanol as a blank. The blank was a sample to which distilled water was added instead of extract.  
The radical scavenging power was expressed as \(\mu\)M Trolox per 1 g sample.  
Determination of Fe Reduction Forces of Acidified Methanol Extractable Polyphenols by the Ferric Reducing Antioxidant Power (FRAP) Method  
Fe reduction forces by the FRAP method were determined according to [PERSON] and Strain [31]. A total of 0.1 mL of extract was measured into a cuvette and increased to 1 mL with distilled water, then 3 mL of FRAP reagent was added. After 10 min, the absorbance of the sample was measured on a spectrophotometer at \(\lambda\) = 593 nm against distilled water as a blank.  
The reduction strength of Fe ions by the method was expressed in \(\mu\)M Trolox per 1 g of sample.