Protective effects of bark ethanolic extract from Spondias dulcis Forst F. against DNA damage induced by benzo[a]pyrene and cyclophosphamide.

This study evaluated the genotoxicity, mutagenicity, antigenotoxicity, and antimutagenicity effects on biochemical parameters of oxidative stress of the Spondias dulcis bark ethanolic extract on mice. The extract was evaluated in the doses of 500, 1000, and 1500 mg/kg bw via gavage. To evaluate the protective effects of the extract, benzo[a]pyrene (B[a]P) and cyclophosphamide (CP) were chosen as DNA damage inducers. Genotoxicity and antigenotoxicity were evaluated by the comet assay. Cytotoxicity, mutagenicity, and antimutagenicity were evaluated by the micronucleus test in bone marrow and peripheral blood. The biochemical parameters of oxidative stress were evaluated by the quantification of catalase activity (CAT) and reduced glutathione (GSH) in total blood, liver and kidney, and malondialdehyde (MDA), in liver and kidney. No genotoxic, cytotoxic, or mutagenic effect was found on mice exposed to the extract. The extract depleted the number of damaged nucleoids in total blood and the number of micronucleus (MN) in both cell types. The extract was able to increase CAT activity and GSH levels and decrease MDA levels after treatment with B[a]P and CP. The results indicate that the S. dulcis extract has potential to be used as preventive compound against DNA damage caused by CP and B[a]P.

Green synthesis of colloidal gold nanoparticles using latex from Hevea brasiliensis and evaluation of their in vitro cytotoxicity and genotoxicity.

Latex extracted from Hevea brasiliensis tree has been used as a green alternative for preparing gold nanoparticles (Au NPs); however, no study evaluating the cytotoxic and genotoxic potential of Au NPs synthesised using H. brasiliensis has been published. The present study aimed to synthesise and characterise colloidal Au NPs using latex from H. brasiliensis and to evaluate their in vitro cytotoxicity and genotoxicity. Ideal conditions for the green synthesis of Au NPs were studied. In vitro cytotoxicity and genotoxicity of Au NPs in CHO-K1 cells was also evaluated. Our findings indicated that the ideal synthesis conditions of pH, temperature, reduction time, and concentrations of latex and HAuCl4 were 7.0, 85°C, 120 min, 3.3 mg/mL, and 5.0 mmol/L, respectively. LC5024 h of Au NPs was 119.164 ± 5.31 µg/mL. Lowest concentration of Au NPs tested presented minimal cytotoxicity and genotoxicity. However, high concentrations of Au NPs promoted DNA damage and cell death via apoptosis. On the basis of these findings, the authors optimised the use of an aqueous solution of H. brasiliensis latex as a reducing/stabilising agent for the green synthesis of Au NPs. Low concentrations of these NPs are biocompatible in normal cell types, suggesting that these NPs may be used in biological applications.

In vitro cytotoxicity and genotoxicity of composite mixtures of natural rubber and leather residues used for textile applications.

A novel composite material has been developed from natural rubber and leather waste, and a corresponding patent has been filed. This new material may be incorporated into textile and footwear products. However, as leather waste contains chromium, the biocompatibility of this new material and its safety for use in humans must be investigated. The aim of the present study was to investigate the presence of chromium in this new material, determine the amount of each form of chromium present (trivalent or hexavalent), and evaluate the potential cytotoxic and genotoxic effects of the novel composite in two cell lines. The cellular viability was quantified using the MTT3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction method and neutral red uptake assay, and genotoxic damage was analyzed using the comet assay. Our findings indicated that the extracts obtained from the composite were severely cytotoxic to both cell lines tested, and additionally highly genotoxic to MRC-5 cells. These biological responses do not appear to be attributable to the presence of chromium, as the trivalent form was predominantly found to be present in the extracts, indicating that hexavalent chromium is not formed during the production of the novel composite. The incorporation of this new material in applications that do not involve direct contact with the human skin is thus indicated, and it is suggested that the chain of production of this material be studied in order to improve its biocompatibility so that it may safely be used in the textile and footwear industries.