Genotoxic effects of Campomanesia xanthocarpa extracts on Allium cepa vegetal system.

UNLABELLED: CONTEXT. Campomanesia xanthocarpa Berg. (Myrtaceae), popularly known in Brazil as guabiroba, is a plant used as antidiarrheic, anti-inflammatory and antirheumatic agents, and in stomach and hepatic disorders. OBJECTIVE: The antiproliferative and genotoxic effects of aqueous extracts and essential oil of C. xanthocarpa were evaluated. MATERIALS AND METHODS: Cytotoxicity and genotoxicity of the aqueous extracts (6 and 30 mg/mL) and essential oil (0.25%, v/v) obtained from leaves of C. xanthocarpa were evaluated using the Allium cepa L. (Amaryllidaceae) assay. Mitotic index was calculated as the percentage of dividing cells of total cells observed; chromosome abnormalities were observed and counted during cell division. Additionally, the composition of the essential oil and the quantification of the main compounds of the extracts were determined by gas chromatography/mass spectrometry and high performance liquid chromatography coupled with diode array detector, respectively. RESULTS AND DISCUSSION: Aqueous extracts (6 and 30 mg/mL) led to a reduction of 67.7% and 34.1% of the mitotic index, respectively, whereas the treatment with essential oil caused a 48.2% reduction in the mitotic index, when compared with negative control. Chromosomal mutations were observed and included anaphase bridges, delay chromosome, break chromosome, as well as metaphase with disorganized chromosomal and binuclear cells. The main compounds of the essential oil were ß-caryophyllene (8.87%), viridiflorol (6.40%), spathulenol (5.16%), δ-cadinene (4.92%), linalool (4.46%) and α-cadinol (4.25%). Gallic acid (3.19%), chlorogenic acid (1.04%), quercetin (2.97%) and rutin (4.82%) were identified in an aqueous extract (30 mg/mL). CONCLUSION: Our results demonstrated that genotoxic and antiproliferative activities are present in C. xanthocarpa infusions using the in vivo onion root-tip cell test.

Pollen viability of Polygala paniculata L. (Polygalaceae) using different staining methods.

Polygala paniculata L. is a medicinal plant that grows in the Brazilian Atlantic coast, known as 'barba-de-São-João', 'barba-de-bode', 'vassourinha branca', and 'mimosa'. In this study, pollen viability was estimated by three different staining methods: 2% acetic orcein, 2% acetic carmine, and Alexander's stain. The young inflorescences of twenty accessions were collected and fixed in a solution of ethanol: acetic acid (3:1) for 24 hours, then stored in ethanol 70% under refrigeration. Six slides per plant, two for each stain, were prepared by squashing, and 300 pollen grains per slide were analyzed. Pollen viability was high (> 70%) for most accessions of P. paniculata using the Alexander's stain, which proved the most adequate method to estimate pollen viability.

Antiproliferative and genotoxic effects of Mikania glomerata (Asteraceae).

Mikania glomerata is a plant used in Brazilian traditional medicine, known as 'guaco'. It possesses anti-inflammatory properties and the aqueous extracts of its leaves are indicated for the treatment of diseases of the respiratory tract. This study aimed at evaluating the antiproliferative and genotoxic effect of Mikania glomerata leaf infusions on the cell cycle of onion. The material used was collected in the native environment from Rio Grande do Sul State, Brazil. Aqueous extracts through infusions were prepared in two concentrations: 4g/L (usual concentration) and 16g/L (4x more concentrated) of each of the populations. Two groups of four onion bulbs for each plant population were used plus a control group. The rootlets were fixed in ethanol-acetic acid (3:1), conserved in ethanol 70% and slides were prepared using the squashing technique colored with orcein 2%. The cells were observed and analyzed during cell cycle. Per group of bulbs, 2000 cells were analyzed, and the mean values of the cell number of each of the phases of the cell cycle were calculated, determining the mitotic index (MI). Statistic analyses of the data were carried out by the x2 ( p= 0.05) test. We conclude that M. glomerata presents both antiproliferative and genotoxic activity.