title: Genotoxic and mutagenic effects of guarana (Paullinia cupana) in prokaryotic organisms.
abstract: Aqueous extracts of Paullinia cupana (guarana), a species that belongs to the Sapindaceae family, were analyzed for the presence of genotoxic activities in bacterial cells. The extracts of guarana were genotoxic as assessed by lysogenic induction in Escherichia coli and they were also able to induce mutagenesis in Salmonella typhimurium. Addition of S9 microsomal fraction, catalase, superoxide dismutase or thiourea counteracted the genotoxic activity of guarana, suggesting that oxygen reactive species play an essential role in the genotoxicity of aqueous guarana extracts. The genotoxic activity in the extracts was related to the presence of a molecular complex formed by caffeine and a flavonoid (catechin or epicatechin) in the presence of potassium.
authors.affiliation: Departamento de Radiobiologia, Instituto de Biofísica Carlos Chagas Filho, Rio de Janeiro, Brazil.
authors.forename: C A
authors.initials: CA
authors.lastname: da Fonseca
authors.forename: J
authors.initials: J
authors.lastname: Leal
authors.forename: S S
authors.initials: SS
authors.lastname: Costa
authors.forename: A C
authors.initials: AC
authors.lastname: Leitão
mesh_terms: D002110:Caffeine / Q000032:analysis; D002374:Catalase / Q000494:pharmacology; D002392:Catechin / Q000032:analysis; D004926:Escherichia coli / Q000187:drug effects; D008862:Microsomes, Liver / Q000378:metabolism; D009152:Mutagenicity Tests; D009154:Mutation; D010936:Plant Extracts / Q000737:chemistry / Q000633:toxicity*; D010946:Plants, Medicinal / Q000737:chemistry*; D011188:Potassium / Q000032:analysis; D012486:Salmonella typhimurium / Q000187:drug effects; D013482:Superoxide Dismutase / Q000494:pharmacology; D014775:Virus Activation / Q000187:drug effects
chemical_list: D010936:Plant Extracts; D002110:Caffeine; D002392:Catechin; D002374:Catalase; D013482:Superoxide Dismutase; D011188:Potassium