title: Evaluation of antioxidant, antimutagenic, and lipid peroxidation inhibitory activities of selected fractions of Holarrhena floribunda (G. Don) leaves.
abstract: Exposure to environmental pollutants often leads to an upsurge in the production of reactive oxygen species (ROS). ROS oxidize cellular fatty acids to produce lipid peroxyl radicals, subsequently transformed into lipid peroxides, which decrease membrane fluidity and increase the activity of various enzymes implicated in degenerative diseases and cancer formation. Edible plants that contain exogenous compounds like curcumeroid, β-carotene, turmeric, and so on, protect the aerobic cells from oxidation of free radicals. This study thus evaluates antioxidant and antimutagenic activities of ethyl acetate, aqueous and methanolic fractions of Holarrhena floribunda leaves. Inhibitory activities of the ethyl acetate fraction on Fe(2+)-induced lipid peroxidation in hen egg yolk; rat liver and brain tissues were also evaluated. The Allium cepa root assay was used to evaluate antimutagenic activity. Results showed that the ethyl acetate scavenged DPPH, OH•, and •O2(-) much stronger than other fractions, as evidenced by its lowest respective IC50 values. All the fractions displayed antimutagenic activities against cyclophosphamide-induced chromosomal aberrations. Likewise, all the fractions induced a reduction in mitotic index, a hallmark of cytotoxicity in the root meristem of Allium cepa. The decrease in mitotic index was most profound for the ethyl acetate fraction, which also demonstrated a significant lipid peroxidation inhibitory activity in the liver and brain homogenates, but not in egg yolk, compared with the ascorbic acid standard. In general, the results suggest that the ethyl acetate fraction might contain beneficial phytochemicals that should be explored as novel candidates for preclinical drug development.
authors.affiliation: Molecular Oncology Laboratory, Department of Medical Biosciences, University of the Western Cape, South Africa and Department of Biochemistry, Ladoke Akintola University of Technology, Ogbomoso, Nigeria.
authors.forename: Jelili A
authors.initials: JA
authors.lastname: Badmus
authors.forename: Oyeronke A
authors.initials: OA
authors.lastname: Odunola
authors.forename: Taofeek A
authors.initials: TA
authors.lastname: Yekeen
authors.forename: Adedapo M
authors.initials: AM
authors.lastname: Gbadegesin
authors.forename: John O
authors.initials: JO
authors.lastname: Fatoki
authors.forename: Muyideen O
authors.initials: MO
authors.lastname: Godo
authors.forename: Kayode S
authors.initials: KS
authors.lastname: Oyebanjo
authors.forename: Donavon C
authors.initials: DC
authors.lastname: Hiss
mesh_terms: D000085:Acetates; D000818:Animals; D016587:Antimutagenic Agents / Q000302:isolation & purification / Q000494:pharmacology*; D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology*; D001923:Brain Chemistry / Q000187:drug effects; D002645:Chickens; D003520:Cyclophosphamide / Q000633:toxicity; D004530:Egg Yolk / Q000737:chemistry; D005609:Free Radicals / Q000037:antagonists & inhibitors; D035462:Holarrhena / Q000737:chemistry*; D006801:Humans; D015227:Lipid Peroxidation / Q000187:drug effects; D008099:Liver / Q000737:chemistry / Q000187:drug effects; D000432:Methanol; D008940:Mitotic Index; D019697:Onions / Q000187:drug effects / Q000235:genetics; D010936:Plant Extracts / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry*; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics; D051381:Rats; D052616:Solid Phase Extraction; D012997:Solvents; D014867:Water
chemical_list: D000085:Acetates; D016587:Antimutagenic Agents; D000975:Antioxidants; D005609:Free Radicals; D010936:Plant Extracts; D012997:Solvents; D014867:Water; C007650:ethyl acetate; D003520:Cyclophosphamide; D000432:Methanol