Table 1.

Effect of UVC light treatments on the content of phenolic acids and flavonoids from acerola fruit determined by LC–MS. Values represent concentration (mg phenolics/100 freeze-dried acerola).

Peak	Retention time (min)	Identification	Day 0		Day 7
			UV−	UV+	UV−	UV+
1c	19.5–20.5	Gallic acid	2.9 a	1.3 d	2.3 b	1.5 c
1d	21.3–22.5	Coumaroyl quinic acid	4.0 c	5.3 b	3.9 c	8.1 a
1e	30.25	Cyanidin 3-rhamnoside	1152 a	416 b	47 d	276 c
2	33.03	Pelargonidin 3-rhamnoside	155 a	60 b	25 c	52 b
3	37.37	Pelargonidin	4 b	7 a	0.37 d	1.6 c
4	41.32	Peonidin-3-xylopyranoside	28 b	156 a	ND	6 c
5	46.19	Cyanidin 3-rutinoside	12 c	67 a	ND	19 b
6	47.04	Kaempferol 3-O-robinobioside-7-O-arabinofuranoside	3 c	1.47 d	5.5 a	3 b
7	53.18	Isorhamnetin 3-O-galactoside	3 a	3 a	ND	2.7 b
8	56.06	Isorhamnetin 3-O-glucoside	17 d	21 c	37 b	43 a
9	57.16	Isorhamnetin	1.2 b	1.1 c	1.3 a	ND
10	60.4	Kaempferol 7-O-neohesperidoside	5 b	3.3 c	3.1 d	7 a
11	65.88	Kaempferol 3-O-arabinofuranoside	10.5 d	13.8 c	17.6 b	18.1 a
12	67.19	Quercetin 3-O-glucoside	2.8 b	2.8 b	0.5 c	4.7 a
13	70.38	Quercitrin-2″-O-gallate	1.1 b	0.8 d	1.9 a	1.0 c
14	73.88	Myricetin-3-O-glucuronide	0.1 b	14.3 a	ND	ND
15	74.36	Myricetin-3-O-glucoside	16.1 b	0.1 c	0.25 c	25.1 a
16	76–77.85	Myricetin rhamnoside	107 c	74 d	196 a	167 b

Values represent the mean of three replicates. Values with different letters within the same compound represent statistical difference (p < 0.05) by the Tukey’s HSD test. Concentration values for each type of compound were determined from chromatogram peak areas and standards (Table S1). Areas of peaks 1e to 5 were quantified at 520 nm (Fraction F4) and areas of peaks 1c, 1d, 6–16 were quantified at 330 nm (Fraction F3).

ND not detected.