ABSTRACT. Luehea divaricata is a native plant of the Brazilian Cerrado, known as "açoita-cavalo". It is used as a popular herbal medicine in the treatment of dysentery, bleeding, arthritis, tumors, ulcers, and gangrenous wounds. Considering that herbal medicines sometimes provoke tumors and/or may prevent mutational events, it is important to study the action of these natural drugs on DNA. Aqueous extract of the bark of L. divaricata was evaluated at three different concentrations (0.10, 0.30, 0.50 mg/mL), individually and in combination with the neoplastic drug doxorubicin (DXR), by the somatic mutation and recombination test (SMART/wing) in Drosophila melanogaster. Distilled water was included as a negative control. The mutation frequency in the treatments with L. divaricata extract alone was not significantly higher than in the negative control for standard (ST) and high bioactivation (HB) crosses. When L. divaricata extract was combined with DXR, there was a significant reduction in the frequency of spots when compared to DXR alone, in both crosses. Further studies with other experimental models would be useful to confirm that L. divaricata extract is not harmful and that it could be used in the prevention of cancer.

ABSTRACT. Palicourea coriacea, popularly known as "douradinha", is a medicinal plant from the Brazilian Cerrado region used in folk medicine to treat kidney and urethral stones and kidney inflammation. We evaluated the cytotoxic, genotoxic, and possible antigenotoxic activities of an aqueous extract of P. coriacea on somatic cells of Drosophila melanogaster, using the somatic mutation and recombination test. We used third-stage larvae of D. melanogaster from a standard cross and a high bioactivation cross and tested 10 different doses of P. coriacea aqueous extract (5, 15, 25, 35, 50, 65, 80, 95, 110, and 125 mg/mL). Doxorubicin (0.125 mg/mL) was used as a positive control and distilled water as a negative control. None of the doses was lethal to the larvae. There was no genotoxic effect at 5, 10, or 15 mg extract/mL. However, a significant decrease in the frequency of spots induced by doxorubicin was observed when administered with P. coriacea aqueous extract at these same doses. We conclude that P. coriacea aqueous extract is not cytotoxic or genotoxic at these doses, but it does protect against the genotoxic action of doxorubicin.

Resumo: O extrato aquoso liofilizado de folhas de Solanum paniculatum L. (jurubeba), planta medicinal muito utilizada pela população como diurético, em tratamentos de fígado e baço e para combater febre e inflamações, foi submetido ao teste SMART/asa em células somáticas de Drosophila melanogaster, para a avaliação de seu potencial mutagênico. Foram usadas três diferentes concentrações do extrato de folhas (2,5 mg.mL -1 , 6,25 mg.mL -1 e 10 mg.mL -1 ), sendo doxorrubicina (DXR) usada como controle positivo e água destilada com adição de sacarose a 5%, como controle negativo. Foram utilizadas

SumaryThe medicinal plant Jacaranda decurrens Cham., known as "carobinha-do-campo", is native to "Cerrado" (open pasture land with patches of stunted vegetation, woody pasture) and it belongs to the family Bignoniaceae. It is used in the popular medicine for the syphilis treatment, diaphoresis, inflammations etc., being prepared in the form of infusions (leaves and bark). We evaluated the mutagenic and antimutagenic activity of J. decurrens in somatic cells of Drosophila melanogaster using the SMART/eye test (somatic mutation and recombination test), which is based on the pigmentation of Drosophila ommatidia. Deletions, point mutations, non-disjunction and somatic recombinations were detected. Larvae in the third instar, resulting in crossing between virgin females from the Yellow lineage and males from the White one were treated with three different concentrations of J. decurrens ethanolic gross extract (EGE): 10 mg/ml (dosage-1); 6.25 mg/ml (dosage-2) and 4.16 mg/ml (dosage-3). They were isolated for mutagenic activity evaluation and associated to urethane (URE) for the antimutagenic analysis. URE was used (4 mg/ml) for the positive control and distilled water for the negative one. Three experiments were carried out for both mutagenesis and antimutagenesis. In the evaluation of the mutagenesis, the amount of clones/cells found in the dosage-3 (10.14) was statistically significant when compared to the negative dosage control (2.31), leading to the conclusion that J. decurrens EGE has a mutagenic effect depending on the concentration. On the other hand, in the antimutagenetic analysis, the EGE showed an antimutagenic effect in the three concentrations (dosage-1ϭ4.18; dosage-2ϭ4.58; and dosage-3ϭ3.24 clones/cells) when compared to the positive control (urethaneϭ6.29 clones/cells). Compared to dosage-3 (more diluted), the EGE presented a larger modulator effect of the genetic damages caused by URE. Thus, considering the established experimental conditions, we concluded that J. decurrens EGE has, depending on the concentration, either a mutagenic effect or a protecting effect of DNA against URE damage.Key words Mutagenis, Antimutagenesis, Drosophila melanogaster, Jacaranda decurrens, SMART/eye.The use of medicinal plants (phytotherapy) is the result of the amount of secular empirical knowledge about the plant actions in several ethnic groups. Therefore, there are many questions