. 2019 Jul 26;24(15):2718. doi: 10.3390/molecules24152718

Table 3.

Quantitative determination of phenolic substances and control samples obtained from wild rice using various solvents: The extraction conditions were 30% of water in DESs; extraction temperature at 50°C; extraction time of 10 min, and solid–liquid ratio of 40 mg/mL. The results are expressed as μg/g of wild rice dry weight (n = 3).

Compound	DES-1	DES-2	DES-3	DES-4	DES-5	DES-6	DES-7	H₂O	30%EtOH	EtOH
Flavonoids
Catechin	12.87 ±0.1^e	23.51 ±0.6^a	11.64 ±0.1^f	10.25 ±0.1^h	15.99 ±0.1^c	12.94 ±0.1^d	nd	nd	17.90 ±0.1^b	10.53 ±0.1^g
Procyanidin B1	11.68 ±0.2^d	10.02 ±0.3^f	8.30 ±0.2^h	12.87 ±0.2^a	10.11 ±0.2^e	8.89 ±0.1^g	7.01 ±0.1^j	7.51 ±0.2ⁱ	11.90 ±0.2^b	11.89 ±0.1^c
Quercetin	18.12 ±0.5^b	21.12 ±0.7^a	15.80 ±0.4^c	15.84 ±0.4^c	15.80 ±0.4^c	nd	15.70 ±0.3^d	15.72 ±0.3^d	15.80 ±0.3^c	14.45 ±0.3^e
Total Flavonoids	42.67	54.65	35.74	38.96	41.90	21.83	22.71	23.23	45.60	36.87
Phenolic acids
Vanillin	11.23 ±0.3^e	9.41 ±0.3ⁱ	8.27 ±0.3^j	10.56 ±0.2^g	13.13 ±0.2^d	18.01 ±0.4^a	15.65 ±0.3^b	10.82 ±0.2^f	14.90 ±0.3^c	9.63 ±0.2^h
p-Hydroxybenzaldehyde	14.40 ±0.1^b	6.08 ±0.3^f	2.24 ±0.1^h	8.96 ±0.4^d	0.32 ±0.2ⁱ	18.82 ±0.3^a	9.56 ±0.1^c	4.64 ±0.2^g	6.96 ±0.2^e	nd
p-Hydroxybenzoic acid	8.48 ±0.1^c	9.52 ±0.2^b	7.92 ±0.2^d	6.96 ±0.2^f	7.60 ±0.2^e	9.60 ±0.3^b	9.28 ±0.2^b	5.52 ±0.1^g	11.36 ±0.2^a	3.44 ±0.1^h
p-Coumaric acid	nd	0.58 ±0.1^f	0.84 ±0.1^f	1.82 ±0.1^e	2.80 ±0.2^d	8.00 ±0.3^a	5.86 ±0.2^b	2.38 ±0.1^d	4.98 ±0.2^c	nd
Protocatechuic acid	3.16 ±0.3ⁱ	2.90 ±0.2^j	4.46 ±0.2^h	7.18 ±0.3^e	9.36 ±0.2^b	8.40 ±0.3^c	11.64 ±0.3^a	4.54 ±0.2^g	7.48 ±0.1^d	5.38 ±0.1^f
Syringic acid	0.02 ±0.1^j	5.52 ±0.3^e	3.24 ±0.3^g	3.64 ±0.3^f	1.92 ±0.2ⁱ	5.88 ±0.3^d	6.02 ±0.3^c	9.42 ±0.3^a	6.54 ±0.2^b	2.26 ±0.2^h
Ferulic acid	94.98 ±0.7^d	114.84 ±1.3^a	107.90 ±1.5^b	7.04 ±0.3^j	58.20 ±0.6ⁱ	77.12 ±0.6^g	80.50 ±0.8^f	58.96 ±0.6^h	85.50 ±0.9^e	111.50 ±0.9^c
Sinapic acid	81.10 ±0.8^e	103.50 ±1.3^a	95.64 ±0.9^b	42.00 ±0.4^h	68.56 ±0.7^f	80.18 ±0.8^e	69.26 ±0.5^f	49.74 ±0.5^g	86.00 ±0.7^d	91.00 ±0.9^c
Vanillic acid	11.28 ±0.2^g	15.24 ±0.3^d	17.04 ±0.3^a	15.32 ±0.2^c	nd	9.58 ±0.1ⁱ	11.38 ±0.2^f	16.74 ±0.2^b	12.88 ±0.2^e	9.74 ±0.1^h
Total phenolic acids	224.65	267.59	247.55	103.48	161.89	235.59	219.15	162.76	236.6	232.95

Values are mean ± standard deviation (n = 3). Values with different letters in the same row indicate significant differences (P < 0.05). nd: not detected.