title: Flavonoids and sesquiterpenes from Tecurium ramosissimum promote antiproliferation of human cancer cells and enhance antioxidant activity: a structure-activity relationship study.
abstract: Fractionation of the chloroformic extracts from Teucrium ramosissimum leaves resulted in the isolation of three flavonoids: genkwanin (1), cirsimaritin (2) and 4',7-dimethoxy apigenin (4) and one sesquiterpene: β-eudesmol (3). The structures were determined using data obtained from (1)H and (13)C NMR spectra, as well as by various correlation experiments (COSY, HMQC and HMBC). The antioxidant activities of the isolated flavonoids from T. ramosissimum leaves were evaluated by measuring their ability to scavenge the radical ABTS(+) and through chemical assays: cupric reducing antioxidant capacity (CUPRAC), reducing power (RP) and ferric reducing antioxidant power (FRAP). Furthermore, the effects of T. ramosissimum isolated molecules, on inhibition of cell proliferation and induction of apoptosis in human leukemia cells, were also examined. Cirsimaritin showed the best activity in the ABTS assay with TEAC value 2.04μM, whereas apigenin and 4',7-dimethoxy apigenin exhibited the highest antioxidant activity using the CUPRAC, RP and FRAP assays with TEAC values 10.5, 1.39 and 0.71μM respectively. The cytotoxic activity revealed that the β-eudesmol inhibited significantly the proliferation of K562 cells (IC(50)=20μg/ml).
authors: Unité de Pharmacognosie/Biologie Moléculaire 99/UR/07-03, Faculté de Pharmacie, Rue Avicenne, 5000 Monastir, Tunisia.
authors: Mohamed
authors: M
authors: Ben Sghaier
authors: Ines
authors: I
authors: Skandrani
authors: Nouha
authors: N
authors: Nasr
authors: Marie-Genviève Dijoux
authors: MG
authors: Franca
authors: Leila
authors: L
authors: Chekir-Ghedira
authors: Kamel
authors: K
authors: Ghedira
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000494:pharmacology*; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004354:Drug Screening Assays, Antitumor; D047309:Flavones / Q000737:chemistry / Q000494:pharmacology; D005419:Flavonoids / Q000737:chemistry* / Q000494:pharmacology*; D006801:Humans; D020014:K562 Cells; D007938:Leukemia / Q000188:drug therapy / Q000473:pathology; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D018515:Plant Leaves / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D012717:Sesquiterpenes / Q000737:chemistry / Q000494:pharmacology*; D013329:Structure-Activity Relationship; D031367:Teucrium / Q000737:chemistry*; D014416:Tunisia
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D000975:Antioxidants; D047309:Flavones; D005419:Flavonoids; D012717:Sesquiterpenes; C007072:cirsimaritin