title: Chemistry and bioactivity of olive biophenols in some antioxidant and antiproliferative in vitro bioassays.
abstract: The major biophenols in olives and the crude extract and ethyl acetate fraction from olive mill waste were studied for their ability to counteract different stages of oxidative damage, that is, hydrogen peroxide, superoxide radical (SOR), and hydroxyl radical in vitro. Antiproliferative activity on colon cancer (HT-29) and gastric cancer (AGS) cell lines was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide bioassay. Emphasis was given to how the observed in vitro activity is controlled by the structural feature of biophenols and possible synergism and antagonism. While in some bioassays, for example, 2,2'-diphenyl-1-picrylhydrazyl, the nonphenolic moiety had minimal affect, it had a significant role in the SOR scavenging bioassay. Verbascoside was more active than caffeic acid or hydroxytyrosol evaluated individually or in equimolar mixtures in some bioassays. Mixtures of biophenols were more active than individual biophenols as antiproliferative agents. Overall, the mixture of hydroxytyrosol/caffeic acid and the biophenol extracts were more effective in protecting DNA from oxidative damage and inhibiting the growth of cancer cells.
authors.affiliation: School of Biomedical Sciences, School of Agricultural and Wine Sciences, E. H. Graham Centre for Agricultural Innovation, Charles Sturt University, Wagga Wagga, NSW 2678, Australia. hobied@csu.edu.au
authors.forename: Hassan K
authors.initials: HK
authors.lastname: Obied
authors.forename: Paul D
authors.initials: PD
authors.lastname: Prenzler
authors.forename: Izabela
authors.initials: I
authors.lastname: Konczak
authors.forename: Ata-U
authors.initials: AU
authors.lastname: Rehman
authors.forename: Kevin
authors.initials: K
authors.lastname: Robards
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D045744:Cell Line, Tumor; D016166:Free Radical Scavengers / Q000494:pharmacology; D006801:Humans; D000069463:Olive Oil; D010636:Phenols / Q000032:analysis / Q000737:chemistry / Q000494:pharmacology*; D010626:Phenylethyl Alcohol / Q000031:analogs & derivatives / Q000737:chemistry / Q000494:pharmacology; D010938:Plant Oils / Q000737:chemistry*; D011714:Pyrans / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000970:Antineoplastic Agents; D000975:Antioxidants; D016166:Free Radical Scavengers; D000069463:Olive Oil; D010636:Phenols; D010938:Plant Oils; D011714:Pyrans; C005975:3,4-dihydroxyphenylethanol; C000352:elenolic acid; D010626:Phenylethyl Alcohol