Bioactive Substances, Heavy Metals, and Antioxidant Activity in Whole Fruit, Peel, and Pulp of Citrus Fruits

Table 3

Content of phenolic acids (mg/100 g) in citrus pulp (F), peel (P), and whole fruits (W).

Fruit/index	Part	Orange	Pomelo	Mandarin	Lemon	Key lime	Red grapefruit	Green grapefruit	White grapefruit
Gallic acid	F	^c	^c	^b	^a	^e	^d	^c	^d
	P	^c	^de	^a	^b	^d	^de	^de	^e
	W	^b	^c	^a	^a	^c	^c	^c	^c
Chlorogenic acid	F	^b	^c	^a	^e	^d	^a	^c	^b
	P	^d	^d	^c	^d	^b	^bc	^d	^a
	W	^c	^c	^b	^d	^bc	^a	^c	^a
Caffeic acid	F	^b	^b	^e	^b	^d	^a	^c	^c
	P	^a	^e	^c	^b	^e	^d	^c	^e
	W	^a	^e	^e	^b	^f	^c	^d	^e
p-Coumaric acid	F	^c	^e	^f	^a	^b	^d	^e	^d
	P	^c	^b	^d	9^d	^a	^d	^cd	^d
	W	12.07^d	17.75^c	5.40^f	20.20^b	^a	8.36^e	7.59^e	8.88^e
	Ferulic acid	F	^c	^d	^c	^b	^b	^a	^d	^e
P		^b	^d	^d	^b	^c	^a	^d	^d
W		^bc	^e	^d	^b	^c	^a	^de	^e
Sinapic acid	F	^b	0.00	0.00	^a	0.00	^b	0.00	0.00
	P	^a	0.00	0.00	0.00	0.00	^b	0.00	0.00
	W	^a	0.00	0.00	^b	0.00	^a	0.00	0.00
Statistical analysis
F^1vs. P
Gallic acid		<0.001	0.614	<0.001	<0.001	0.988	<0.001	<0.001	<0.001
Chlorogenic acid		<0.001	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
Caffeic acid		<0.001	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
p-Coumaric acid		0.014	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001
Ferulic acid		<0.001	<0.001	0.005	<0.001	<0.001	<0.001	<0.001	<0.001
Sinapic acid		<0.001	—	—	<0.001	—	<0.001	—	—
F^2vs. W
Gallic acid		0.063	0.040	0.085	0.036	0.138	0.046	0.016	0.005
Chlorogenic acid		<0.001	0.002	0.012	<0.001	<0.001	0.045	0.139	0.009
Caffeic acid		<0.001	<0.001	<0.001	<0.001	0.019	<0.001	<0.001	<0.001
p-Coumaric acid		0.989	<0.001	<0.001	<0.001	<0.001	0.032	<0.001	0.138
Ferulic acid		0.008	<0.001	0.023	<0.001	0.439	<0.001	<0.001	<0.001
Sinapic acid		0.083	—	—	<0.001	—	0.001	—	—

^a,b,c,d,e,fValues in rows with different letters are significantly different at : F rows—superscript letters indicate statistically significant differences in phenolic acid content in the pulp (F) between citrus cultivars; P rows—superscript letters indicate statistically significant differences in phenolic acid content in the peel (P) between citrus cultivars. The results of two-way analysis of variance (ANOVA). W rows—superscript letters indicate statistically significant differences in phenolic acid content in the whole fruit (W) between citrus cultivars. ^1,2Legend: see Table 1.