Preventive effects of dill oil on potassium bromated-induced oxidative DNA damage in garlic root tips

Abstract

In this study, the potential antimutagenic/cytoprotective effect of the oil extract (2.5µg/ml) from Anethum graveolens L. (Dill) on oxidative DNA damage was tested. The experiments were carried out to inhibit mutagenicity induced by potassium bromated (KBrO₃-9g/l) in Allium assay using mitotic activities and nuclear DNA contents. Result showed a clear reduction in radical length in all KBrO₃-treated groups compared to control plants. Mitotic activity, measured by mitotic index (MI) and mitotic stages, were significantly decreased in meristematic cells after KBrO₃ application, The results showed that mitotic index (MI) was decreased to reach about 0.8 at 24 hrs compared with 23.9% in untreated plants. The analysis of potential cyto and genoprotective of dill extract on nuclear DNA contents showed a statistically significant increase in the nuclear DNA content compared to KBrO₃-treated roots was observed. Clearly, dill oil showed highly performance in protecting the mitotic cells against mutagenic KBrO₃ effects by increasing the MI and decreasing the abnormal chromosomes. Also, the percentage of damage reduction was observed in the pre- (28.9, 57.9 and 46.4 %), simultaneous (53.0, 70.6 and  35.7 %) and post- (37.3, 61.8 and 50 %) treatment. The results of the qualitative study showed that this dill extracts were rich in chemical compounds belonging to several phytochemical classes. GC-MS analysis detected 29 chemical compounds with different concentrations. The predominant ones were Octadecanoic acid (31.75%) and 2-pentanone, 4-hydroxy-4-methyl (16.77). So that these experiments will help to understand and uncover the mechanism of action dill oil against the mutagenic effects of KBrO₃ (i.e whether they have a prophylactic or treatment activity).