Date Palm Seed Oil (Phoenix dactylifera L.) Green Extraction: Physicochemical Properties, Antioxidant Activities, and Phenolic and Fatty Acid Profiles

Table 4

Percentage of phenolic compound of different seed oils

Extraction method	Soxhlet				Soaking in essential oil
	Ether petroleum		Essential oil
	mg/100g	%	mg/100g	%	mg/100g	%
Gallic acid	34.89 ± 4.31a	38.20	23.55 ± 0.06b	6.82	20.12 ± 1.38b	5.00
Protocatchuic acid	N.D.		82.67 ± 0.57a	23.95	75.29 ± 6.15b	18.70
Chlorogenic acid	N.D.		79.94 ± 6.49a	23.16	99.71 ± 0.52b	24.76
4-O-Caffeoylquinic acid	0.86 ± 0.86c	0.94	81.45 ± 6.61b	23.59	101.45 ± 0.52a	25.20
Syringic acid	4.37 ± 0.37b	4.78	10.76 ± 0.06a	3.12	10.47 ± 0.46a	2.60
p-Coumaric acid	32.01 ± 0.17ab	35.05	31.63 ± 0.00b	9.16b	32.85 ± 0.75a	8.16
trans-Ferulic acid	6.15 ± 0.06b	6.73	7.62 ± 0.17b	2.21	10.52 ± 2.47a	2.61
Hyperoside quercetin-3-o-galactoside	0.69 ± a	0.76	N.D.		N.D.
Rutin	0.63 ± 0.03a	0.69	1.22 ± 0.06a	0.35	0.58 ± 0.07a	0.14
o-Coumaric acid	11.26 ± 0.11b	12.34	12.44 ± 0.11a	3.60	11.45 ± 0.29b	2.84
Apigenin-7-o-glucoside	0.06 ± 0.06a	0.06	N.D.		N.D.
(E)-Cinnamic	N.D.		11.69 ± 0.63b	3.38	35.87 ± 3.51a	8.91
Naringenin	N.D.		N.D.		2.44 ± 1.03a	0.61
Cirsilineol	0.40 ± 0.06c	0.44	1.16 ± 0.00a	0.34	0.70 ± 0.23b	0.17
Acacetin	N.D.		1.10 ± 0.29a	0.32	1.22 ± 0.06a	0.30
Total phenolic mg/100 g	91.32 ± 0.52c		345.23 ± 8.85b		402.67 ± 14.60a

N.D., not detected. Mean and standard deviation values with the same letter within the same parameter were not significantly different ().