Bioactive Flavonoids, Antioxidant Behaviour, and Cytoprotective Effects of Dried Grapefruit Peels (Citrus paradisi Macf.)

Table 2

Spectral data of flavonoids in grapefruit peel extracts.

Tentative identification	RT	UVmax	MS [M − H]^−	MS [M + H]^+	Products ions
	(min)	λ (nm)	()	()	()
Isonaringin [32, 41]	31.43	217, 284, 331	579		271, 151
Naringin [32, 41]	33.58	224, 283, 331	579		459, 271
Hesperidin [32, 41]	38.02	225, 284, 328	609		301
Neohesperidin [41]	40.19	228, 283, 331	609		301, 489
Unknown-1	44.65	283, 328		617	465, 303
Unknown-2	46.57	249, 257, 324		595	449, 287
Naringenin [42]	48.04	226, 284, 325		273	153
Hesperetin [40]	51.98	225, 285, 329		303	285
Isosinensetin [40]	53.46	249, 270, 342		373	357, 343, 327
Sinensetin [32, 40, 43]	54.54	243, 264, 333		373	358, 343, 312
Unknown-3	56.22	250, 272, 335		403	388, 373
Nobiletin [40, 43]	57.60	248, 268, 334		403	388, 373
Tangeretin [32, 40]	59.42	271, 322		373	358, 343, 325, 297

References given in brackets are taken from papers with matching spectral data:
Angeloni et al. 2012 [32]; Rivas et al. 2008 [40]; Jeong et al. 2004 [41]; Xu et al. 2007 [42]; Alañón et al. 2011 [43].