Bioguided isolation and identification of the nonvolatile antioxidant compounds from fennel (Foeniculum vulgare Mill.) waste.
A bioguided isolation of an aqueous extract of fennel waste led to the isolation of 12 major phenolic compounds. Liquid chromatography coupled to atmospheric pressure chemical ionization mass spectrometry (LC/UV/APCI-MS) combined with spectroscopic methods (NMR) was used for compound identification. Radical scavenging activity was tested using three methods: DPPH*, superoxide nitro-blue tetrazolium hypoxanthine/xanthine oxidase, and *OH/luminol chemiluminescence. In addition to products described in the literature, eight antioxidant compounds were isolated and identified for the first time in fennel: 3-caffeoylquinic acid, 4-caffeoylquinic acid, 1,5-O-dicaffeoylquinic acid, rosmarinic acid, eriodictyol-7-O-rutinoside, quercetin-3-O-galactoside, kaempferol-3-O-rutinoside, and kaempferol-3-O-glucoside. The structures of eriodictyol-7-O-rutinoside and quercetin-3-O-glucuronide were completely elucidated by two-dimensional NMR experiments. The isolated compounds exhibited a strong antiradical scavenging activity, which may contribute to the interpretation of the pharmacological effects of fennel.
Parejo
Irene
I
Departament de Productes Naturals, Biologia Vegetal i Edafologia, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII, s/n, 08028 Barcelona, Catalunya, Spain.
Viladomat
Francesc
F
Bastida
Jaume
J
Schmeda-Hirschmann
Guillermo
G
Burillo
Jesús
J
Codina
Carles
C
D000975:Antioxidants / Q000032:analysis* / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid; D005419:Flavonoids / Q000032:analysis / Q000302:isolation & purification; D030001:Foeniculum / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D009822:Oils, Volatile / Q000737:chemistry; D010636:Phenols / Q000032:analysis* / Q000302:isolation & purification*
D000975:Antioxidants; D005419:Flavonoids; D009822:Oils, Volatile; D010636:Phenols