Antigenotoxic potential of plant leaf extracts of Parkinsonia aculeata L. using Allium cepa assay.

The aim of the present study was to evaluate the antigenotoxic potential of P. aculeata L. leaf extract/fractions against maleic hydrazide (MH) using Allium cepa root chromosomal aberration assay. The excessive reduction in root growth and mitotic index value was observed after 3 h treatment of MH as compared to negative control (water). In case of MH treatment, frequency of aberrated cells significantly (p ≤ 0.05) raised from 129 to 337 at 0.1 ppm and 2.0 ppm concentrations respectively. From root growth inhibition test with MH treatment, EC50 value i.e. 0.5 ppm was selected to study the antigenotoxic effect of different extract/fractions of P. aculeata L. leaves. All the extract/fractions showed increase in mitotic index and great reduction in chromosomal aberrations with rise in concentration against the genotoxicity of MH. Among all the extract/fractions, butanol and ethyl acetate fractions showed significant reduction in chromosomal aberrations in A. cepa cells and indicates the chemo preventive activity. Antigenotoxic property of this plant is due to the presence of various phytochemicals in leaf such as epi-orientin, Parkinsonin-A, Parkinsonin-B, orientin, iso-orientin, vitexin, iso-vitexin, C-glycosylflavone, parkintin, rotenoids, terpenoids, flavonoids, saponins, alkaloids, glycosides and anthraquinone etc. Our result showed that among all the treatments, simultaneous treatment showed best result followed by pre and post treatment. Further studies in animal model are suggested for further evaluation of the use of P. aculeata leaf extract in human welfare.

Carboxymethylcellulose improves the antimutagenic activity of sodium selenite against maleic hydrazide in Vicia faba seedlings.

In this study the genotoxic effects induced by a treatment with different doses of sodium selenite in Vicia faba seedlings were evaluated with or without the addition of carboxymethylcellulose. A further objective of this study was to verify whether the adduct selenite-carboxymethylcellulose was also able to reduce the genotoxic damages induced by the herbicide maleic hydrazide, a strong mutagenic agent in plants, at a higher extent than selenite alone. The results obtained showed a genotoxic activity of sodium selenite at concentrations up to 8.6 mg L-1. In the treatments with selenite-carboxymethylcellulose, the genotoxicity induced by the complex was significantly lower in comparison to how much was observed in the treatment with selenite only. When sodium selenite's protective activity against the genotoxic effects induced by the herbicide maleic hydrazide was tested, a reduction of mutagenic damages was observed at the highest application doses of selenite (from 86 mg L-1). The treatments with selenite-carboxymethylcellulose resulted in a further increase of selenium protective activity, which was observable for all doses used. These findings suggest a possible role played by carboxymethylcellulose in the regulation of the genotoxic activity of selenium.

Prophylaxis of antioxidants against the genotoxicity of methyl mercuric chloride and maleic hydrazide in Allium micronucleus assay.

Antioxidants, namely cysteine, 2.46 x 10(-5) M; glutathione 9.75 x 10(-6), 9.75 x 10(-4) M; vitamin C, 10(-2) M; mannitol, 5 x 10(-2) M; potassium iodide, 5 x 10(-2) M and sodium selenite, 1.73 x 10(-6) M; were tested for their prophylactic activity against the genotoxicity of methylmercuric chloride, 1.26 x 10(-6) M and maleic hydrazide, 3 x 10(-4) M in Allium micronucleus assay. Antioxidants doses were administered simultaneously or prior to the genotoxic exposures. The results from the present experiments indicated that antioxidants conferred protection against the genotoxicity of both methyl mercuric chloride and maleic hydrazide. Furthermore, the protection of GSH against methyl mercuric chloride depending on the concentration persisted for 12 h.

Desmutagenic activity of natural humic acids: inhibition of mitomycin C and maleic hydrazide mutagenicity.

Humic acids are natural components of organic matter widespread in the environment. In spite of the incomplete knowledge about their composition, increasing interest in humic acid activity is justified by their ubiquity. Four different humic acids have been tested in Chinese hamster ovary cells in vitro, both alone and in combination with two well-known mutagens (mitomycin C and maleic hydrazide). Data about sister-chromatid exchanges, mitotic and proliferation indices were collected. Our results, on the whole, indicate: (i) a slight mutagenicity and toxicity of tested humic acids, probably due to chlorination during sample preparation; (ii) a desmutagenic rather than antimutagenic activity of the tested humic acids.