Table 2.

Identification of phenolics and flavonoids present in red pitaya.

Polyphenols	Chemical Structure	Molecular Formula	Concentrations (Dry Weight)	References
Phenolic compounds
Caffeic acid		C9H8O4	20.1 ± 19.6 mg/100 g	[23,32]
Ferulic acid		C10H10O4	14.37 ± 9.3 mg/100 g	[33]
Protocatechuic acid		C7H6O4	10.32 ± 4.8 mg/100 g	[34]
p-Coumaric acid		C9H8O3	1.52 ± 1.4 mg/100 g	[35]
Sinapic acid		C11H12O5	1.12 ± 0.8 mg/100 g	[23]
Vanillic acid		C8H8O4	0.918 ± 0.4 mg/100 g	[23]
Gallic acid		C7H6O5	159.7 ± 19.7 µg/100 g	[36]
o-Coumaric acid		C9H8O3	199.4 ± 49.5 µg/100 g	[23]
t-Cinnamic acid		C9H8O2	51.7 ± 44.1 µg/100 g	[23]
Salicylic acid		C7H6O3	50.2 ± 20.3 µg/100 g	[23]
Syringic acid		C9H10O5	65.10 ± 0.04 µg/100 g	[37]
Flavonoids
Catechin		C15H14O6	3.60 ± 2.33 mg/g	[25]
Quercetin		C15H10O7	1.31 ± 0.45 mg/g	[25]
Epicatechin		C15H14O6	30.77 ± 0.04 µg/100 g	[37]
Epigallocatechin gallate		C22H18O11	58.99 ± 0.01 µg/100 g	[38]
Procyanidin B1		C30H26O12	1325.61 ± 0.07 µg/100 g	[39]
Procyanidin B2		C30H26O12	589.26 ± 0.03 µg/100 g	[39]
Kaempferol 3-glucoside		C21H20O11	39.69 ± 0.02 µg/100 g	[37]
Quercetin 3-glucoside		C21H20O12	31.93 ± 0.04 µg/100 g	[37]
Rutin		C27H30O16	26.57 ± 0.04 µg/100 g	[37]
Anthocyanins
Cyanidin 3-glucoside		C21H21O11	12.67 ± 0.63 mg/100 g	[25]
Delphinidin 3-glucoside		C21H21ClO12	0.82 ± 0.17 mg/100 g	[25]
Pelargonidin 3-glucoside		C21H21O10	1.76 ± 0.23 mg/100 g	[25]