Optimization Conditions of Ultrasound-Assisted Extraction for Phenolic Compounds and Antioxidant Activity from Rubus alceifolius Poir Leaves

Table 4

Chemical compounds of R.A. Poir leaf extract.

Peak	Compounds	Retention time (min)	Ultrasound-assisted extraction (UAE; mg/100 g)	Soxhlet extraction (SE; mg/100 g)	Maceration extraction (ME; mg/100 g)
1	Catechol	3.54
2	2,3-Dihydro-benzofuran	4.95
3	p-Hydroxybenzoic acid	12.56
4	Gentisic acid	13.89
5	Gallic acid	14.09
6	Vanillic acid	14.38
7	Benzaldehyde, 2-hydroxy-4-methyl	14.94
8	Catechin	16.01
9	Gallocatechin	17.31
10	Coumaroylquinic acid	18.32
11	Quinic acid	19.14		—	—
12	Quercetin	20.11

Different letters in the same row indicate statistically significant differences between treatments (). The values are of duplicate runs.