title: Protective effects of alpha-tocopherol and beta-carotene on para-nonylphenol-induced inhibition of cell growth, cellular respiration and glucose-induced proton extrusion of bacteria.
abstract: para-Nonylphenol (NP) showed a dose-dependent inhibition against the cell growth of Bacillus subtilis, Micrococcus luteus, Pseudomonas aeruginosa and Staphylococcus aureus at 5-100 microM. However, other typical plastic-derived endocrine disruptors such as bisphenol A and di-2-ethylhexyl phthalate (DEHP) did not significantly affect the cell growth of these bacteria at 5-100 microM. The NP-induced cell growth inhibition was restored when concomitantly supplemented with lipophilic antioxidants such as alpha-tocopherol and beta-carotene, but not with hydrophilic antioxidants, ascorbic acid and (-)-epigallocatechin gallate (EGCG). NP also suppressed in a dose-dependent manner cellular oxygen consumption and glucose-induced proton extrusion of these bacteria at 10-100 microM. Both effects were prevented when added with alpha-tocopherol and beta-carotene, but not with ascorbic acid and EGCG. The significance of these results is discussed from the viewpoint of environmental microbiology and a possible biochemical mechanism of the inhibitory effect of NP is suggested.
authors.affiliation: Department of Human Life Science, Osaka Kun-Ei Women's College, Set's City, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Okai
authors.forename: K
authors.initials: K
authors.lastname: Higashi-Okai
authors.forename: K
authors.initials: K
authors.lastname: Machida
authors.forename: H
authors.initials: H
authors.lastname: Nakamura
authors.forename: K
authors.initials: K
authors.lastname: Nakayama
authors.forename: K
authors.initials: K
authors.lastname: Fijita
authors.forename: T
authors.initials: T
authors.lastname: Tanaka
authors.forename: M
authors.initials: M
authors.lastname: Taniguchi
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D004579:Electron Transport / Q000187:drug effects; D005947:Glucose / Q000494:pharmacology; D010101:Oxygen Consumption / Q000187:drug effects; D010636:Phenols / Q000494:pharmacology*; D011522:Protons; D014810:Vitamin E / Q000494:pharmacology*; D019207:beta Carotene / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D010636:Phenols; D011522:Protons; D019207:beta Carotene; D014810:Vitamin E; C041594:4-nonylphenol; D005947:Glucose