Mutation Research 497 (2001) 139–145 Investigation of genotoxic and antigenotoxic activities of chlorophylls and chlorophyllin in cultured V79 cells G.C. Bez a , B.Q. Jordão a , V.E.P. Vicentini b , M.S. Mantovani a,∗ a Departamento de Biologia Geral, Centro de Ciências Biológicas, Universidade Estadual de Londrina, Londrina, Paraná, Brazil b Departamento de Biologia Celular e Genética, Centro de Ciências Biológicas, Universidade Estadual de Maringá, Maringá, Paraná, Brazil Received 25 October 2000; received in revised form 30 May 2001; accepted 20 June 2001 Abstract Chlorophyll and its derivatives are examples of plant compounds (purified and/or extracted) which appear to protect DNA from damage caused by chemical or physical agents, although some studies have identified clastogenic activity of these compounds. This study was carried out to assess the genotoxic activity of chlorophyll-a (Chl-a), -b (Chl-b) and chlorophyllin (Chl) and their antigenotoxic activity against the DNA damage induced by methyl methanesulphonate (MMS) under conditions of simultaneous, pre-, post-treatment, and simultaneous treatment after pre-incubation of the chemical with MMS. The micronucleus (MN) test was used in binucleated cells (induced by cytocalasin-B) of a mammalian cell line (V79). The three concentrations of Chl-a, Chl-b or Chl (0.1375, 0.275, 0.55 M) were not genotoxic and the genotoxic action of MMS (400 M) decreased (74–117%) under all treatment conditions. The results showed that there was no significant difference among the treatment types, the concentration or the nature of chlorophyll used. The data obtained suggest that Chl-a, Chl-b and Chl when associated with the DNA damaging agent, MMS, may protect the DNA by desgenotoxic action and/or by bio-antigenotoxic mechanisms, with the similar efficiency. © 2001 Elsevier Science B.V. All rights reserved. Keywords: Chlorophyll; Antigenotoxic; Cell culture; Micronucleus test; Chlorophyllin 1. Introduction The constant exposure of the human population to toxic environmental agents has led to intense research on naturally plant products that reduce genotoxic ef- fects [1]. Chlorophyll and its derivatives have been widely studied for their ability to protect against damage to DNA induced by clastogenic, mutagenic or carcinogenic agents in different test systems [1–7]. However, other studies have shown that both chlorophyll and chlorophyllin (Chl) can present am- biguous genotoxic and carcinogenic effects [1,8,9]. ∗ Corresponding author. E-mail address: biomsm@uel.br (M.S. Mantovani). Chlorophyll has a planar head of porphyrine with a magnesium nucleus and a long phytol tail. Chloro- phyllin is a chlorophyll derivative where the magne- sium nucleus is substituted for another metal such as cobalt, copper or iron and the ester groups phytin and methyl are substituted by sodium or potassium by careful hydrolysis [10]. Some authors have suggested that both chlorophyll and chlorophyllin inhibit genotoxicity by forming a reversible complex with the mutagenic agent, acting as desmutagenic molecules or interceptors [3,11,12]. Others have also suggested that these compounds may act by capturing free radicals, blocking active radicals of the mutagenic agents or as a stabilizing membrane [11,13]. However, a better understanding of the role 1383-5718/01/$ – see front matter © 2001 Elsevier Science B.V. All rights reserved. PII:S1383-5718(01)00251-0