The effects of different extraction solvents on the yield and antioxidant properties of Nigella sativa oil from Saudi Arabia

Figures & data

Figure 1. Pictures of Nigella sativa: (A) Plant, (B) Seeds and (C) Extracted oil.

Figure 2. Absorption spectra of for Nigella sativa seed oil extract collected from Saudi Arabia.

Table 1. The yield and antioxidant activities of Nigella sativa seed oil using TPC, DPPH, and FRAP assays.

Solvents Type	Yield (%)	TPC (mg GAE/gDW)	DPPH (inhabitation %)	FRAP (mmol/100 gDW)
CH3OH	21.16	116.39 ± 4.79	59 ± 0.50	11321.24 ± 210
C2H5OH	40.16	106.94 ± 6.59	54 ± 1.40	13199.67 ± 138
CoPr	21.73	50.62 ± 3.56	34 ± 1.47	3091.48 ± 37
THF	29.19	104.00 ± 3.00	49 ± 1.29	13326.46 ± 550
Mix	18.41	238.80 ± 3.63	16 ± 1.59	11442.92 ± 127
CH2Cl2	23.20	62.46 ± 3.15	42 ± 0.65	7457.340 ± 252
C6H14	32.90	151.35 ± 3.74	44 ± 1.38	10525.09 ± 274

Figure 3. Total Phenolic Content (TPC) of Nigella sativa seed oil using different solvents.

Figure 4. Effect of different solvents on inhibition of Nigella sativa seed oil using 2,2-Diphenyl-1-Picrylhydrazyl (DPPH).

Figure 5. Effect of different solvents on Nigella sativa seed oil using Radical Scavenging Activity (FRAP).

Table 2. ANOVA results for TPC, DPPH, and FRAP.

Assay	Source	Sum of squares	Mean square	F-value	P-value
TPC	Between Groups	1.6103	0.2684	1053	9.26E′−18	Significant
	Within Groups	0.0036	0.0003
	Total	1.6139
DPPH	Between Groups	0.8465	0.1411	268	1.25E−13	Significant
	Within Groups	0.0074	0.0005
	Total	0.8539
FRAP	Between Groups	7.9285	1.3214	766	8.56E−17	Significant
	Within Groups	0.0242	0.0017
	Total	7.9527

Figure A1. The standard calibration curve of Gallic acid was separately obtained by plotting the absorbance versus concentrations (0–40 µg/mL) used for TPC test.

Figure A2. The standard calibration curve of Trolox was separately obtained by plotting the absorbance versus concentrations (0–15 mg/mL) used for DPPH assay.

Figure A3. The calibration curve of Fe²⁺ with linearity range of 0–10 µM used for FRAP assay.