الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 284 |  |  |
| | | from | 284 | | |
Abstract
Purified extract of phycocyanin (purity 1.8) from Spirulina platensis was tested for genotoxic and inhibitory effect against mutagenicity produced by curzate fungicide on Vicia faba and Allium cepa. Selected concentration of 0.2% of aqueous solution of phycocyanin pigment was found to be antigenotoxic and anticlastogenic dose against different concentrations of curzate. Present study was achieved at two levels, cytological and molecular studies.
Results of cytological studies indicated that two experimental agents are similar in their mode of action on mitosis, meiosis and produce similar types of aberrations, where stickiness was found to be the most obvious kind. However, mixing curzate with 0.2% of aqueous solution of phycocyanin leads to increasing mitotic activity of Vicia faba and Allium cepa plants and decreasing percentage of total abnormalities of mitotic and meiotic division compared with different concentrations of curzate alone. So phycocyanin acts as antigenotoxic and anticlastogenic against fungicide.
Results of molecular studies on M1 progeny were carried out by using SDS-PAGE and RAPD tests on protein and DNA respectively, indicating that mixing fungicide with 0.2% of aqueous solution of phycocyanin increase number of unaffected bands, decreasing number of appeared and disappeared bands, and changes in relative mobilities and band intensity. RAPD results demonstrated polymorphic numbers of genetic bands, which were the electrophoretic products of PCR for different treatments by using five primer pairs. The most effective primer OPG-05, which identify the mutagenic variations among two treatments. Changes of protein RAPD PCR analysis banding patterns may be correlated with the cytological abnormalities which lead to the loss of some of genetic materials and appearance of new characteristic band. This give us clear evidence that phycocyanin as antigenotoxic and anticlastogenic agent can reduce the ability of fungicide to produce DNA structural variations.
Key words: Phycocyanin, Anticlastogenic agent, Cytological study, Molecular study.